6756 lines
227 KiB
C
6756 lines
227 KiB
C
/* stb_image - v2.12 - public domain image loader - http://nothings.org/stb_image.h
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no warranty implied; use at your own risk
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Do this:
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#define STB_IMAGE_IMPLEMENTATION
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before you include this file in *one* C or C++ file to create the implementation.
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// i.e. it should look like this:
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#include ...
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#include ...
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#include ...
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#define STB_IMAGE_IMPLEMENTATION
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#include "stb_image.h"
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You can #define STBI_ASSERT(x) before the #include to avoid using assert.h.
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And #define STBI_MALLOC, STBI_REALLOC, and STBI_FREE to avoid using malloc,realloc,free
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QUICK NOTES:
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Primarily of interest to game developers and other people who can
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avoid problematic images and only need the trivial interface
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JPEG baseline & progressive (12 bpc/arithmetic not supported, same as stock IJG lib)
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PNG 1/2/4/8-bit-per-channel (16 bpc not supported)
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TGA (not sure what subset, if a subset)
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BMP non-1bpp, non-RLE
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PSD (composited view only, no extra channels, 8/16 bit-per-channel)
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GIF (*comp always reports as 4-channel)
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HDR (radiance rgbE format)
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PIC (Softimage PIC)
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PNM (PPM and PGM binary only)
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Animated GIF still needs a proper API, but here's one way to do it:
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http://gist.github.com/urraka/685d9a6340b26b830d49
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- decode from memory or through FILE (define STBI_NO_STDIO to remove code)
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- decode from arbitrary I/O callbacks
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- SIMD acceleration on x86/x64 (SSE2) and ARM (NEON)
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Full documentation under "DOCUMENTATION" below.
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Revision 2.00 release notes:
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- Progressive JPEG is now supported.
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- PPM and PGM binary formats are now supported, thanks to Ken Miller.
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- x86 platforms now make use of SSE2 SIMD instructions for
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JPEG decoding, and ARM platforms can use NEON SIMD if requested.
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This work was done by Fabian "ryg" Giesen. SSE2 is used by
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default, but NEON must be enabled explicitly; see docs.
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With other JPEG optimizations included in this version, we see
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2x speedup on a JPEG on an x86 machine, and a 1.5x speedup
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on a JPEG on an ARM machine, relative to previous versions of this
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library. The same results will not obtain for all JPGs and for all
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x86/ARM machines. (Note that progressive JPEGs are significantly
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slower to decode than regular JPEGs.) This doesn't mean that this
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is the fastest JPEG decoder in the land; rather, it brings it
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closer to parity with standard libraries. If you want the fastest
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decode, look elsewhere. (See "Philosophy" section of docs below.)
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See final bullet items below for more info on SIMD.
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- Added STBI_MALLOC, STBI_REALLOC, and STBI_FREE macros for replacing
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the memory allocator. Unlike other STBI libraries, these macros don't
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support a context parameter, so if you need to pass a context in to
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the allocator, you'll have to store it in a global or a thread-local
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variable.
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- Split existing STBI_NO_HDR flag into two flags, STBI_NO_HDR and
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STBI_NO_LINEAR.
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STBI_NO_HDR: suppress implementation of .hdr reader format
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STBI_NO_LINEAR: suppress high-dynamic-range light-linear float API
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- You can suppress implementation of any of the decoders to reduce
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your code footprint by #defining one or more of the following
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symbols before creating the implementation.
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STBI_NO_JPEG
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STBI_NO_PNG
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STBI_NO_BMP
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STBI_NO_PSD
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STBI_NO_TGA
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STBI_NO_GIF
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STBI_NO_HDR
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STBI_NO_PIC
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STBI_NO_PNM (.ppm and .pgm)
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- You can request *only* certain decoders and suppress all other ones
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(this will be more forward-compatible, as addition of new decoders
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doesn't require you to disable them explicitly):
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STBI_ONLY_JPEG
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STBI_ONLY_PNG
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STBI_ONLY_BMP
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STBI_ONLY_PSD
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STBI_ONLY_TGA
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STBI_ONLY_GIF
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STBI_ONLY_HDR
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STBI_ONLY_PIC
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STBI_ONLY_PNM (.ppm and .pgm)
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Note that you can define multiples of these, and you will get all
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of them ("only x" and "only y" is interpreted to mean "only x&y").
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- If you use STBI_NO_PNG (or _ONLY_ without PNG), and you still
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want the zlib decoder to be available, #define STBI_SUPPORT_ZLIB
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- Compilation of all SIMD code can be suppressed with
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#define STBI_NO_SIMD
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It should not be necessary to disable SIMD unless you have issues
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compiling (e.g. using an x86 compiler which doesn't support SSE
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intrinsics or that doesn't support the method used to detect
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SSE2 support at run-time), and even those can be reported as
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bugs so I can refine the built-in compile-time checking to be
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smarter.
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- The old STBI_SIMD system which allowed installing a user-defined
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IDCT etc. has been removed. If you need this, don't upgrade. My
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assumption is that almost nobody was doing this, and those who
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were will find the built-in SIMD more satisfactory anyway.
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- RGB values computed for JPEG images are slightly different from
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previous versions of stb_image. (This is due to using less
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integer precision in SIMD.) The C code has been adjusted so
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that the same RGB values will be computed regardless of whether
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SIMD support is available, so your app should always produce
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consistent results. But these results are slightly different from
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previous versions. (Specifically, about 3% of available YCbCr values
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will compute different RGB results from pre-1.49 versions by +-1;
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most of the deviating values are one smaller in the G channel.)
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- If you must produce consistent results with previous versions of
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stb_image, #define STBI_JPEG_OLD and you will get the same results
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you used to; however, you will not get the SIMD speedups for
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the YCbCr-to-RGB conversion step (although you should still see
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significant JPEG speedup from the other changes).
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Please note that STBI_JPEG_OLD is a temporary feature; it will be
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removed in future versions of the library. It is only intended for
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near-term back-compatibility use.
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Latest revision history:
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2.12 (2016-04-02) fix typo in 2.11 PSD fix that caused crashes
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2.11 (2016-04-02) 16-bit PNGS; enable SSE2 in non-gcc x64
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RGB-format JPEG; remove white matting in PSD;
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allocate large structures on the stack;
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correct channel count for PNG & BMP
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2.10 (2016-01-22) avoid warning introduced in 2.09
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2.09 (2016-01-16) 16-bit TGA; comments in PNM files; STBI_REALLOC_SIZED
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2.08 (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA
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2.07 (2015-09-13) partial animated GIF support
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limited 16-bit PSD support
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minor bugs, code cleanup, and compiler warnings
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2.06 (2015-04-19) fix bug where PSD returns wrong '*comp' value
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2.05 (2015-04-19) fix bug in progressive JPEG handling, fix warning
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2.04 (2015-04-15) try to re-enable SIMD on MinGW 64-bit
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2.03 (2015-04-12) additional corruption checking
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stbi_set_flip_vertically_on_load
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fix NEON support; fix mingw support
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2.02 (2015-01-19) fix incorrect assert, fix warning
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2.01 (2015-01-17) fix various warnings
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2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG
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2.00 (2014-12-25) optimize JPEG, including x86 SSE2 & ARM NEON SIMD
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progressive JPEG
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PGM/PPM support
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STBI_MALLOC,STBI_REALLOC,STBI_FREE
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STBI_NO_*, STBI_ONLY_*
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GIF bugfix
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See end of file for full revision history.
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============================ Contributors =========================
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Image formats Extensions, features
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Sean Barrett (jpeg, png, bmp) Jetro Lauha (stbi_info)
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Nicolas Schulz (hdr, psd) Martin "SpartanJ" Golini (stbi_info)
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Jonathan Dummer (tga) James "moose2000" Brown (iPhone PNG)
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Jean-Marc Lienher (gif) Ben "Disch" Wenger (io callbacks)
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Tom Seddon (pic) Omar Cornut (1/2/4-bit PNG)
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Thatcher Ulrich (psd) Nicolas Guillemot (vertical flip)
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Ken Miller (pgm, ppm) Richard Mitton (16-bit PSD)
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urraka@github (animated gif) Junggon Kim (PNM comments)
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Daniel Gibson (16-bit TGA)
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Optimizations & bugfixes
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Fabian "ryg" Giesen
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Arseny Kapoulkine
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Bug & warning fixes
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Marc LeBlanc David Woo Guillaume George Martins Mozeiko
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Christpher Lloyd Martin Golini Jerry Jansson Joseph Thomson
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Dave Moore Roy Eltham Hayaki Saito Phil Jordan
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Won Chun Luke Graham Johan Duparc Nathan Reed
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the Horde3D community Thomas Ruf Ronny Chevalier Nick Verigakis
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Janez Zemva John Bartholomew Michal Cichon svdijk@github
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Jonathan Blow Ken Hamada Tero Hanninen Baldur Karlsson
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Laurent Gomila Cort Stratton Sergio Gonzalez romigrou@github
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Aruelien Pocheville Thibault Reuille Cass Everitt Matthew Gregan
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Ryamond Barbiero Paul Du Bois Engin Manap snagar@github
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Michaelangel007@github Oriol Ferrer Mesia socks-the-fox
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Blazej Dariusz Roszkowski
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LICENSE
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This software is dual-licensed to the public domain and under the following
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license: you are granted a perpetual, irrevocable license to copy, modify,
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publish, and distribute this file as you see fit.
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*/
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#ifndef STBI_INCLUDE_STB_IMAGE_H
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#define STBI_INCLUDE_STB_IMAGE_H
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// DOCUMENTATION
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//
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// Limitations:
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// - no 16-bit-per-channel PNG
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// - no 12-bit-per-channel JPEG
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// - no JPEGs with arithmetic coding
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// - no 1-bit BMP
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// - GIF always returns *comp=4
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//
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// Basic usage (see HDR discussion below for HDR usage):
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// int x,y,n;
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// unsigned char *data = stbi_load(filename, &x, &y, &n, 0);
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// // ... process data if not NULL ...
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// // ... x = width, y = height, n = # 8-bit components per pixel ...
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// // ... replace '0' with '1'..'4' to force that many components per pixel
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// // ... but 'n' will always be the number that it would have been if you said 0
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// stbi_image_free(data)
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//
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// Standard parameters:
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// int *x -- outputs image width in pixels
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// int *y -- outputs image height in pixels
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// int *comp -- outputs # of image components in image file
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// int req_comp -- if non-zero, # of image components requested in result
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//
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// The return value from an image loader is an 'unsigned char *' which points
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// to the pixel data, or NULL on an allocation failure or if the image is
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// corrupt or invalid. The pixel data consists of *y scanlines of *x pixels,
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// with each pixel consisting of N interleaved 8-bit components; the first
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// pixel pointed to is top-left-most in the image. There is no padding between
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// image scanlines or between pixels, regardless of format. The number of
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// components N is 'req_comp' if req_comp is non-zero, or *comp otherwise.
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// If req_comp is non-zero, *comp has the number of components that _would_
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// have been output otherwise. E.g. if you set req_comp to 4, you will always
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// get RGBA output, but you can check *comp to see if it's trivially opaque
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// because e.g. there were only 3 channels in the source image.
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//
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// An output image with N components has the following components interleaved
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// in this order in each pixel:
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//
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// N=#comp components
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// 1 grey
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// 2 grey, alpha
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// 3 red, green, blue
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// 4 red, green, blue, alpha
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//
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// If image loading fails for any reason, the return value will be NULL,
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// and *x, *y, *comp will be unchanged. The function stbi_failure_reason()
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// can be queried for an extremely brief, end-user unfriendly explanation
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// of why the load failed. Define STBI_NO_FAILURE_STRINGS to avoid
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// compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly
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// more user-friendly ones.
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//
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// Paletted PNG, BMP, GIF, and PIC images are automatically depalettized.
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//
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// ===========================================================================
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//
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// Philosophy
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//
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// stb libraries are designed with the following priorities:
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//
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// 1. easy to use
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// 2. easy to maintain
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// 3. good performance
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//
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// Sometimes I let "good performance" creep up in priority over "easy to maintain",
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// and for best performance I may provide less-easy-to-use APIs that give higher
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// performance, in addition to the easy to use ones. Nevertheless, it's important
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// to keep in mind that from the standpoint of you, a client of this library,
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// all you care about is #1 and #3, and stb libraries do not emphasize #3 above all.
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//
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// Some secondary priorities arise directly from the first two, some of which
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// make more explicit reasons why performance can't be emphasized.
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//
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// - Portable ("ease of use")
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// - Small footprint ("easy to maintain")
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// - No dependencies ("ease of use")
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//
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// ===========================================================================
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//
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// I/O callbacks
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//
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// I/O callbacks allow you to read from arbitrary sources, like packaged
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// files or some other source. Data read from callbacks are processed
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// through a small internal buffer (currently 128 bytes) to try to reduce
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// overhead.
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//
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// The three functions you must define are "read" (reads some bytes of data),
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// "skip" (skips some bytes of data), "eof" (reports if the stream is at the end).
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//
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// ===========================================================================
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//
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// SIMD support
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//
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// The JPEG decoder will try to automatically use SIMD kernels on x86 when
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// supported by the compiler. For ARM Neon support, you must explicitly
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// request it.
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//
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// (The old do-it-yourself SIMD API is no longer supported in the current
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// code.)
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//
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// On x86, SSE2 will automatically be used when available based on a run-time
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// test; if not, the generic C versions are used as a fall-back. On ARM targets,
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// the typical path is to have separate builds for NEON and non-NEON devices
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// (at least this is true for iOS and Android). Therefore, the NEON support is
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// toggled by a build flag: define STBI_NEON to get NEON loops.
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//
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// The output of the JPEG decoder is slightly different from versions where
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// SIMD support was introduced (that is, for versions before 1.49). The
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// difference is only +-1 in the 8-bit RGB channels, and only on a small
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// fraction of pixels. You can force the pre-1.49 behavior by defining
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// STBI_JPEG_OLD, but this will disable some of the SIMD decoding path
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// and hence cost some performance.
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//
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// If for some reason you do not want to use any of SIMD code, or if
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// you have issues compiling it, you can disable it entirely by
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// defining STBI_NO_SIMD.
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//
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// ===========================================================================
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//
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// HDR image support (disable by defining STBI_NO_HDR)
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//
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// stb_image now supports loading HDR images in general, and currently
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// the Radiance .HDR file format, although the support is provided
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// generically. You can still load any file through the existing interface;
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// if you attempt to load an HDR file, it will be automatically remapped to
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// LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1;
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// both of these constants can be reconfigured through this interface:
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//
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// stbi_hdr_to_ldr_gamma(2.2f);
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// stbi_hdr_to_ldr_scale(1.0f);
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//
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// (note, do not use _inverse_ constants; stbi_image will invert them
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// appropriately).
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//
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// Additionally, there is a new, parallel interface for loading files as
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// (linear) floats to preserve the full dynamic range:
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//
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// float *data = stbi_loadf(filename, &x, &y, &n, 0);
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//
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// If you load LDR images through this interface, those images will
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// be promoted to floating point values, run through the inverse of
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// constants corresponding to the above:
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//
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// stbi_ldr_to_hdr_scale(1.0f);
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// stbi_ldr_to_hdr_gamma(2.2f);
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//
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// Finally, given a filename (or an open file or memory block--see header
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// file for details) containing image data, you can query for the "most
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// appropriate" interface to use (that is, whether the image is HDR or
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// not), using:
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//
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// stbi_is_hdr(char *filename);
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//
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// ===========================================================================
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//
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// iPhone PNG support:
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//
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// By default we convert iphone-formatted PNGs back to RGB, even though
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// they are internally encoded differently. You can disable this conversion
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// by by calling stbi_convert_iphone_png_to_rgb(0), in which case
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// you will always just get the native iphone "format" through (which
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// is BGR stored in RGB).
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//
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// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per
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// pixel to remove any premultiplied alpha *only* if the image file explicitly
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// says there's premultiplied data (currently only happens in iPhone images,
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// and only if iPhone convert-to-rgb processing is on).
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//
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#ifndef STBI_NO_STDIO
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#include <stdio.h>
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#endif // STBI_NO_STDIO
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#define STBI_VERSION 1
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enum
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{
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STBI_default = 0, // only used for req_comp
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STBI_grey = 1,
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STBI_grey_alpha = 2,
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STBI_rgb = 3,
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STBI_rgb_alpha = 4
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};
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typedef unsigned char stbi_uc;
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#ifdef __cplusplus
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extern "C" {
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#endif
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#ifdef STB_IMAGE_STATIC
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#define STBIDEF static
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#else
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#define STBIDEF extern
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#endif
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//////////////////////////////////////////////////////////////////////////////
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//
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// PRIMARY API - works on images of any type
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//
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//
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// load image by filename, open file, or memory buffer
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//
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typedef struct
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{
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int (*read) (void *user,char *data,int size); // fill 'data' with 'size' bytes. return number of bytes actually read
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void (*skip) (void *user,int n); // skip the next 'n' bytes, or 'unget' the last -n bytes if negative
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int (*eof) (void *user); // returns nonzero if we are at end of file/data
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} stbi_io_callbacks;
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STBIDEF stbi_uc *stbi_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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STBIDEF stbi_uc *stbi_load_from_memory (stbi_uc const *buffer, int len , int *x, int *y, int *comp, int req_comp);
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STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk , void *user, int *x, int *y, int *comp, int req_comp);
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#ifndef STBI_NO_STDIO
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STBIDEF stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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// for stbi_load_from_file, file pointer is left pointing immediately after image
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#endif
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#ifndef STBI_NO_LINEAR
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STBIDEF float *stbi_loadf (char const *filename, int *x, int *y, int *comp, int req_comp);
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STBIDEF float *stbi_loadf_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
|
|
STBIDEF float *stbi_loadf_from_callbacks (stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp);
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
STBIDEF float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
|
|
#endif
|
|
#endif
|
|
|
|
#ifndef STBI_NO_HDR
|
|
STBIDEF void stbi_hdr_to_ldr_gamma(float gamma);
|
|
STBIDEF void stbi_hdr_to_ldr_scale(float scale);
|
|
#endif // STBI_NO_HDR
|
|
|
|
#ifndef STBI_NO_LINEAR
|
|
STBIDEF void stbi_ldr_to_hdr_gamma(float gamma);
|
|
STBIDEF void stbi_ldr_to_hdr_scale(float scale);
|
|
#endif // STBI_NO_LINEAR
|
|
|
|
// stbi_is_hdr is always defined, but always returns false if STBI_NO_HDR
|
|
STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user);
|
|
STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len);
|
|
#ifndef STBI_NO_STDIO
|
|
STBIDEF int stbi_is_hdr (char const *filename);
|
|
STBIDEF int stbi_is_hdr_from_file(FILE *f);
|
|
#endif // STBI_NO_STDIO
|
|
|
|
|
|
// get a VERY brief reason for failure
|
|
// NOT THREADSAFE
|
|
STBIDEF const char *stbi_failure_reason (void);
|
|
|
|
// free the loaded image -- this is just free()
|
|
STBIDEF void stbi_image_free (void *retval_from_stbi_load);
|
|
|
|
// get image dimensions & components without fully decoding
|
|
STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
|
|
STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp);
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
STBIDEF int stbi_info (char const *filename, int *x, int *y, int *comp);
|
|
STBIDEF int stbi_info_from_file (FILE *f, int *x, int *y, int *comp);
|
|
|
|
#endif
|
|
|
|
|
|
|
|
// for image formats that explicitly notate that they have premultiplied alpha,
|
|
// we just return the colors as stored in the file. set this flag to force
|
|
// unpremultiplication. results are undefined if the unpremultiply overflow.
|
|
STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply);
|
|
|
|
// indicate whether we should process iphone images back to canonical format,
|
|
// or just pass them through "as-is"
|
|
STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert);
|
|
|
|
// flip the image vertically, so the first pixel in the output array is the bottom left
|
|
STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip);
|
|
|
|
// ZLIB client - used by PNG, available for other purposes
|
|
|
|
STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen);
|
|
STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header);
|
|
STBIDEF char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen);
|
|
STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
|
|
|
|
STBIDEF char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen);
|
|
STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
|
|
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
//
|
|
//
|
|
//// end header file /////////////////////////////////////////////////////
|
|
#endif // STBI_INCLUDE_STB_IMAGE_H
|
|
|
|
#ifdef STB_IMAGE_IMPLEMENTATION
|
|
|
|
#if defined(STBI_ONLY_JPEG) || defined(STBI_ONLY_PNG) || defined(STBI_ONLY_BMP) \
|
|
|| defined(STBI_ONLY_TGA) || defined(STBI_ONLY_GIF) || defined(STBI_ONLY_PSD) \
|
|
|| defined(STBI_ONLY_HDR) || defined(STBI_ONLY_PIC) || defined(STBI_ONLY_PNM) \
|
|
|| defined(STBI_ONLY_ZLIB)
|
|
#ifndef STBI_ONLY_JPEG
|
|
#define STBI_NO_JPEG
|
|
#endif
|
|
#ifndef STBI_ONLY_PNG
|
|
#define STBI_NO_PNG
|
|
#endif
|
|
#ifndef STBI_ONLY_BMP
|
|
#define STBI_NO_BMP
|
|
#endif
|
|
#ifndef STBI_ONLY_PSD
|
|
#define STBI_NO_PSD
|
|
#endif
|
|
#ifndef STBI_ONLY_TGA
|
|
#define STBI_NO_TGA
|
|
#endif
|
|
#ifndef STBI_ONLY_GIF
|
|
#define STBI_NO_GIF
|
|
#endif
|
|
#ifndef STBI_ONLY_HDR
|
|
#define STBI_NO_HDR
|
|
#endif
|
|
#ifndef STBI_ONLY_PIC
|
|
#define STBI_NO_PIC
|
|
#endif
|
|
#ifndef STBI_ONLY_PNM
|
|
#define STBI_NO_PNM
|
|
#endif
|
|
#endif
|
|
|
|
#if defined(STBI_NO_PNG) && !defined(STBI_SUPPORT_ZLIB) && !defined(STBI_NO_ZLIB)
|
|
#define STBI_NO_ZLIB
|
|
#endif
|
|
|
|
|
|
#include <stdarg.h>
|
|
#include <stddef.h> // ptrdiff_t on osx
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
|
|
#include <math.h> // ldexp
|
|
#endif
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
#include <stdio.h>
|
|
#endif
|
|
|
|
#ifndef STBI_ASSERT
|
|
#include <assert.h>
|
|
#define STBI_ASSERT(x) assert(x)
|
|
#endif
|
|
|
|
|
|
#ifndef _MSC_VER
|
|
#ifdef __cplusplus
|
|
#define stbi_inline inline
|
|
#else
|
|
#define stbi_inline
|
|
#endif
|
|
#else
|
|
#define stbi_inline __forceinline
|
|
#endif
|
|
|
|
|
|
#ifdef _MSC_VER
|
|
typedef unsigned short stbi__uint16;
|
|
typedef signed short stbi__int16;
|
|
typedef unsigned int stbi__uint32;
|
|
typedef signed int stbi__int32;
|
|
#else
|
|
#include <stdint.h>
|
|
typedef uint16_t stbi__uint16;
|
|
typedef int16_t stbi__int16;
|
|
typedef uint32_t stbi__uint32;
|
|
typedef int32_t stbi__int32;
|
|
#endif
|
|
|
|
// should produce compiler error if size is wrong
|
|
typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1];
|
|
|
|
#ifdef _MSC_VER
|
|
#define STBI_NOTUSED(v) (void)(v)
|
|
#else
|
|
#define STBI_NOTUSED(v) (void)sizeof(v)
|
|
#endif
|
|
|
|
#ifdef _MSC_VER
|
|
#define STBI_HAS_LROTL
|
|
#endif
|
|
|
|
#ifdef STBI_HAS_LROTL
|
|
#define stbi_lrot(x,y) _lrotl(x,y)
|
|
#else
|
|
#define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y))))
|
|
#endif
|
|
|
|
#if defined(STBI_MALLOC) && defined(STBI_FREE) && (defined(STBI_REALLOC) || defined(STBI_REALLOC_SIZED))
|
|
// ok
|
|
#elif !defined(STBI_MALLOC) && !defined(STBI_FREE) && !defined(STBI_REALLOC) && !defined(STBI_REALLOC_SIZED)
|
|
// ok
|
|
#else
|
|
#error "Must define all or none of STBI_MALLOC, STBI_FREE, and STBI_REALLOC (or STBI_REALLOC_SIZED)."
|
|
#endif
|
|
|
|
#ifndef STBI_MALLOC
|
|
#define STBI_MALLOC(sz) malloc(sz)
|
|
#define STBI_REALLOC(p,newsz) realloc(p,newsz)
|
|
#define STBI_FREE(p) free(p)
|
|
#endif
|
|
|
|
#ifndef STBI_REALLOC_SIZED
|
|
#define STBI_REALLOC_SIZED(p,oldsz,newsz) STBI_REALLOC(p,newsz)
|
|
#endif
|
|
|
|
// x86/x64 detection
|
|
#if defined(__x86_64__) || defined(_M_X64)
|
|
#define STBI__X64_TARGET
|
|
#elif defined(__i386) || defined(_M_IX86)
|
|
#define STBI__X86_TARGET
|
|
#endif
|
|
|
|
#if defined(__GNUC__) && (defined(STBI__X86_TARGET) || defined(STBI__X64_TARGET)) && !defined(__SSE2__) && !defined(STBI_NO_SIMD)
|
|
// NOTE: not clear do we actually need this for the 64-bit path?
|
|
// gcc doesn't support sse2 intrinsics unless you compile with -msse2,
|
|
// (but compiling with -msse2 allows the compiler to use SSE2 everywhere;
|
|
// this is just broken and gcc are jerks for not fixing it properly
|
|
// http://www.virtualdub.org/blog/pivot/entry.php?id=363 )
|
|
#define STBI_NO_SIMD
|
|
#endif
|
|
|
|
#if defined(__MINGW32__) && defined(STBI__X86_TARGET) && !defined(STBI_MINGW_ENABLE_SSE2) && !defined(STBI_NO_SIMD)
|
|
// Note that __MINGW32__ doesn't actually mean 32-bit, so we have to avoid STBI__X64_TARGET
|
|
//
|
|
// 32-bit MinGW wants ESP to be 16-byte aligned, but this is not in the
|
|
// Windows ABI and VC++ as well as Windows DLLs don't maintain that invariant.
|
|
// As a result, enabling SSE2 on 32-bit MinGW is dangerous when not
|
|
// simultaneously enabling "-mstackrealign".
|
|
//
|
|
// See https://github.com/nothings/stb/issues/81 for more information.
|
|
//
|
|
// So default to no SSE2 on 32-bit MinGW. If you've read this far and added
|
|
// -mstackrealign to your build settings, feel free to #define STBI_MINGW_ENABLE_SSE2.
|
|
#define STBI_NO_SIMD
|
|
#endif
|
|
|
|
#if !defined(STBI_NO_SIMD) && (defined(STBI__X86_TARGET) || defined(STBI__X64_TARGET))
|
|
#define STBI_SSE2
|
|
#include <emmintrin.h>
|
|
|
|
#ifdef _MSC_VER
|
|
|
|
#if _MSC_VER >= 1400 // not VC6
|
|
#include <intrin.h> // __cpuid
|
|
static int stbi__cpuid3(void)
|
|
{
|
|
int info[4];
|
|
__cpuid(info,1);
|
|
return info[3];
|
|
}
|
|
#else
|
|
static int stbi__cpuid3(void)
|
|
{
|
|
int res;
|
|
__asm {
|
|
mov eax,1
|
|
cpuid
|
|
mov res,edx
|
|
}
|
|
return res;
|
|
}
|
|
#endif
|
|
|
|
#define STBI_SIMD_ALIGN(type, name) __declspec(align(16)) type name
|
|
|
|
static int stbi__sse2_available()
|
|
{
|
|
int info3 = stbi__cpuid3();
|
|
return ((info3 >> 26) & 1) != 0;
|
|
}
|
|
#else // assume GCC-style if not VC++
|
|
#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
|
|
|
|
static int stbi__sse2_available()
|
|
{
|
|
#if defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) >= 408 // GCC 4.8 or later
|
|
// GCC 4.8+ has a nice way to do this
|
|
return __builtin_cpu_supports("sse2");
|
|
#else
|
|
// portable way to do this, preferably without using GCC inline ASM?
|
|
// just bail for now.
|
|
return 0;
|
|
#endif
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
// ARM NEON
|
|
#if defined(STBI_NO_SIMD) && defined(STBI_NEON)
|
|
#undef STBI_NEON
|
|
#endif
|
|
|
|
#ifdef STBI_NEON
|
|
#include <arm_neon.h>
|
|
// assume GCC or Clang on ARM targets
|
|
#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
|
|
#endif
|
|
|
|
#ifndef STBI_SIMD_ALIGN
|
|
#define STBI_SIMD_ALIGN(type, name) type name
|
|
#endif
|
|
|
|
///////////////////////////////////////////////
|
|
//
|
|
// stbi__context struct and start_xxx functions
|
|
|
|
// stbi__context structure is our basic context used by all images, so it
|
|
// contains all the IO context, plus some basic image information
|
|
typedef struct
|
|
{
|
|
stbi__uint32 img_x, img_y;
|
|
int img_n, img_out_n;
|
|
|
|
stbi_io_callbacks io;
|
|
void *io_user_data;
|
|
|
|
int read_from_callbacks;
|
|
int buflen;
|
|
stbi_uc buffer_start[128];
|
|
|
|
stbi_uc *img_buffer, *img_buffer_end;
|
|
stbi_uc *img_buffer_original, *img_buffer_original_end;
|
|
} stbi__context;
|
|
|
|
|
|
static void stbi__refill_buffer(stbi__context *s);
|
|
|
|
// initialize a memory-decode context
|
|
static void stbi__start_mem(stbi__context *s, stbi_uc const *buffer, int len)
|
|
{
|
|
s->io.read = NULL;
|
|
s->read_from_callbacks = 0;
|
|
s->img_buffer = s->img_buffer_original = (stbi_uc *) buffer;
|
|
s->img_buffer_end = s->img_buffer_original_end = (stbi_uc *) buffer+len;
|
|
}
|
|
|
|
// initialize a callback-based context
|
|
static void stbi__start_callbacks(stbi__context *s, stbi_io_callbacks *c, void *user)
|
|
{
|
|
s->io = *c;
|
|
s->io_user_data = user;
|
|
s->buflen = sizeof(s->buffer_start);
|
|
s->read_from_callbacks = 1;
|
|
s->img_buffer_original = s->buffer_start;
|
|
stbi__refill_buffer(s);
|
|
s->img_buffer_original_end = s->img_buffer_end;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
|
|
static int stbi__stdio_read(void *user, char *data, int size)
|
|
{
|
|
return (int) fread(data,1,size,(FILE*) user);
|
|
}
|
|
|
|
static void stbi__stdio_skip(void *user, int n)
|
|
{
|
|
fseek((FILE*) user, n, SEEK_CUR);
|
|
}
|
|
|
|
static int stbi__stdio_eof(void *user)
|
|
{
|
|
return feof((FILE*) user);
|
|
}
|
|
|
|
static stbi_io_callbacks stbi__stdio_callbacks =
|
|
{
|
|
stbi__stdio_read,
|
|
stbi__stdio_skip,
|
|
stbi__stdio_eof,
|
|
};
|
|
|
|
static void stbi__start_file(stbi__context *s, FILE *f)
|
|
{
|
|
stbi__start_callbacks(s, &stbi__stdio_callbacks, (void *) f);
|
|
}
|
|
|
|
//static void stop_file(stbi__context *s) { }
|
|
|
|
#endif // !STBI_NO_STDIO
|
|
|
|
static void stbi__rewind(stbi__context *s)
|
|
{
|
|
// conceptually rewind SHOULD rewind to the beginning of the stream,
|
|
// but we just rewind to the beginning of the initial buffer, because
|
|
// we only use it after doing 'test', which only ever looks at at most 92 bytes
|
|
s->img_buffer = s->img_buffer_original;
|
|
s->img_buffer_end = s->img_buffer_original_end;
|
|
}
|
|
|
|
#ifndef STBI_NO_JPEG
|
|
static int stbi__jpeg_test(stbi__context *s);
|
|
static stbi_uc *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PNG
|
|
static int stbi__png_test(stbi__context *s);
|
|
static stbi_uc *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_BMP
|
|
static int stbi__bmp_test(stbi__context *s);
|
|
static stbi_uc *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_TGA
|
|
static int stbi__tga_test(stbi__context *s);
|
|
static stbi_uc *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PSD
|
|
static int stbi__psd_test(stbi__context *s);
|
|
static stbi_uc *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_HDR
|
|
static int stbi__hdr_test(stbi__context *s);
|
|
static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PIC
|
|
static int stbi__pic_test(stbi__context *s);
|
|
static stbi_uc *stbi__pic_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_GIF
|
|
static int stbi__gif_test(stbi__context *s);
|
|
static stbi_uc *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PNM
|
|
static int stbi__pnm_test(stbi__context *s);
|
|
static stbi_uc *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp);
|
|
static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp);
|
|
#endif
|
|
|
|
// this is not threadsafe
|
|
static const char *stbi__g_failure_reason;
|
|
|
|
STBIDEF const char *stbi_failure_reason(void)
|
|
{
|
|
return stbi__g_failure_reason;
|
|
}
|
|
|
|
static int stbi__err(const char *str)
|
|
{
|
|
stbi__g_failure_reason = str;
|
|
return 0;
|
|
}
|
|
|
|
static void *stbi__malloc(size_t size)
|
|
{
|
|
return STBI_MALLOC(size);
|
|
}
|
|
|
|
// stbi__err - error
|
|
// stbi__errpf - error returning pointer to float
|
|
// stbi__errpuc - error returning pointer to unsigned char
|
|
|
|
#ifdef STBI_NO_FAILURE_STRINGS
|
|
#define stbi__err(x,y) 0
|
|
#elif defined(STBI_FAILURE_USERMSG)
|
|
#define stbi__err(x,y) stbi__err(y)
|
|
#else
|
|
#define stbi__err(x,y) stbi__err(x)
|
|
#endif
|
|
|
|
#define stbi__errpf(x,y) ((float *)(size_t) (stbi__err(x,y)?NULL:NULL))
|
|
#define stbi__errpuc(x,y) ((unsigned char *)(size_t) (stbi__err(x,y)?NULL:NULL))
|
|
|
|
STBIDEF void stbi_image_free(void *retval_from_stbi_load)
|
|
{
|
|
STBI_FREE(retval_from_stbi_load);
|
|
}
|
|
|
|
#ifndef STBI_NO_LINEAR
|
|
static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_HDR
|
|
static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp);
|
|
#endif
|
|
|
|
static int stbi__vertically_flip_on_load = 0;
|
|
|
|
STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip)
|
|
{
|
|
stbi__vertically_flip_on_load = flag_true_if_should_flip;
|
|
}
|
|
|
|
static unsigned char *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
#ifndef STBI_NO_JPEG
|
|
if (stbi__jpeg_test(s)) return stbi__jpeg_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
#ifndef STBI_NO_PNG
|
|
if (stbi__png_test(s)) return stbi__png_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
#ifndef STBI_NO_BMP
|
|
if (stbi__bmp_test(s)) return stbi__bmp_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
#ifndef STBI_NO_GIF
|
|
if (stbi__gif_test(s)) return stbi__gif_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
#ifndef STBI_NO_PSD
|
|
if (stbi__psd_test(s)) return stbi__psd_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
#ifndef STBI_NO_PIC
|
|
if (stbi__pic_test(s)) return stbi__pic_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
#ifndef STBI_NO_PNM
|
|
if (stbi__pnm_test(s)) return stbi__pnm_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi__hdr_test(s)) {
|
|
float *hdr = stbi__hdr_load(s, x,y,comp,req_comp);
|
|
return stbi__hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
|
|
}
|
|
#endif
|
|
|
|
#ifndef STBI_NO_TGA
|
|
// test tga last because it's a crappy test!
|
|
if (stbi__tga_test(s))
|
|
return stbi__tga_load(s,x,y,comp,req_comp);
|
|
#endif
|
|
|
|
return stbi__errpuc("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
|
|
static unsigned char *stbi__load_flip(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char *result = stbi__load_main(s, x, y, comp, req_comp);
|
|
|
|
if (stbi__vertically_flip_on_load && result != NULL) {
|
|
int w = *x, h = *y;
|
|
int depth = req_comp ? req_comp : *comp;
|
|
int row,col,z;
|
|
stbi_uc temp;
|
|
|
|
// @OPTIMIZE: use a bigger temp buffer and memcpy multiple pixels at once
|
|
for (row = 0; row < (h>>1); row++) {
|
|
for (col = 0; col < w; col++) {
|
|
for (z = 0; z < depth; z++) {
|
|
temp = result[(row * w + col) * depth + z];
|
|
result[(row * w + col) * depth + z] = result[((h - row - 1) * w + col) * depth + z];
|
|
result[((h - row - 1) * w + col) * depth + z] = temp;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
#ifndef STBI_NO_HDR
|
|
static void stbi__float_postprocess(float *result, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
if (stbi__vertically_flip_on_load && result != NULL) {
|
|
int w = *x, h = *y;
|
|
int depth = req_comp ? req_comp : *comp;
|
|
int row,col,z;
|
|
float temp;
|
|
|
|
// @OPTIMIZE: use a bigger temp buffer and memcpy multiple pixels at once
|
|
for (row = 0; row < (h>>1); row++) {
|
|
for (col = 0; col < w; col++) {
|
|
for (z = 0; z < depth; z++) {
|
|
temp = result[(row * w + col) * depth + z];
|
|
result[(row * w + col) * depth + z] = result[((h - row - 1) * w + col) * depth + z];
|
|
result[((h - row - 1) * w + col) * depth + z] = temp;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
|
|
static FILE *stbi__fopen(char const *filename, char const *mode)
|
|
{
|
|
FILE *f;
|
|
#if defined(_MSC_VER) && _MSC_VER >= 1400
|
|
if (0 != fopen_s(&f, filename, mode))
|
|
f=0;
|
|
#else
|
|
f = fopen(filename, mode);
|
|
#endif
|
|
return f;
|
|
}
|
|
|
|
|
|
STBIDEF stbi_uc *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
FILE *f = stbi__fopen(filename, "rb");
|
|
unsigned char *result;
|
|
if (!f) return stbi__errpuc("can't fopen", "Unable to open file");
|
|
result = stbi_load_from_file(f,x,y,comp,req_comp);
|
|
fclose(f);
|
|
return result;
|
|
}
|
|
|
|
STBIDEF stbi_uc *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char *result;
|
|
stbi__context s;
|
|
stbi__start_file(&s,f);
|
|
result = stbi__load_flip(&s,x,y,comp,req_comp);
|
|
if (result) {
|
|
// need to 'unget' all the characters in the IO buffer
|
|
fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR);
|
|
}
|
|
return result;
|
|
}
|
|
#endif //!STBI_NO_STDIO
|
|
|
|
STBIDEF stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_mem(&s,buffer,len);
|
|
return stbi__load_flip(&s,x,y,comp,req_comp);
|
|
}
|
|
|
|
STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
|
|
return stbi__load_flip(&s,x,y,comp,req_comp);
|
|
}
|
|
|
|
#ifndef STBI_NO_LINEAR
|
|
static float *stbi__loadf_main(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char *data;
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi__hdr_test(s)) {
|
|
float *hdr_data = stbi__hdr_load(s,x,y,comp,req_comp);
|
|
if (hdr_data)
|
|
stbi__float_postprocess(hdr_data,x,y,comp,req_comp);
|
|
return hdr_data;
|
|
}
|
|
#endif
|
|
data = stbi__load_flip(s, x, y, comp, req_comp);
|
|
if (data)
|
|
return stbi__ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
|
|
return stbi__errpf("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
|
|
STBIDEF float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_mem(&s,buffer,len);
|
|
return stbi__loadf_main(&s,x,y,comp,req_comp);
|
|
}
|
|
|
|
STBIDEF float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
|
|
return stbi__loadf_main(&s,x,y,comp,req_comp);
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
STBIDEF float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
float *result;
|
|
FILE *f = stbi__fopen(filename, "rb");
|
|
if (!f) return stbi__errpf("can't fopen", "Unable to open file");
|
|
result = stbi_loadf_from_file(f,x,y,comp,req_comp);
|
|
fclose(f);
|
|
return result;
|
|
}
|
|
|
|
STBIDEF float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_file(&s,f);
|
|
return stbi__loadf_main(&s,x,y,comp,req_comp);
|
|
}
|
|
#endif // !STBI_NO_STDIO
|
|
|
|
#endif // !STBI_NO_LINEAR
|
|
|
|
// these is-hdr-or-not is defined independent of whether STBI_NO_LINEAR is
|
|
// defined, for API simplicity; if STBI_NO_LINEAR is defined, it always
|
|
// reports false!
|
|
|
|
STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len)
|
|
{
|
|
#ifndef STBI_NO_HDR
|
|
stbi__context s;
|
|
stbi__start_mem(&s,buffer,len);
|
|
return stbi__hdr_test(&s);
|
|
#else
|
|
STBI_NOTUSED(buffer);
|
|
STBI_NOTUSED(len);
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
STBIDEF int stbi_is_hdr (char const *filename)
|
|
{
|
|
FILE *f = stbi__fopen(filename, "rb");
|
|
int result=0;
|
|
if (f) {
|
|
result = stbi_is_hdr_from_file(f);
|
|
fclose(f);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
STBIDEF int stbi_is_hdr_from_file(FILE *f)
|
|
{
|
|
#ifndef STBI_NO_HDR
|
|
stbi__context s;
|
|
stbi__start_file(&s,f);
|
|
return stbi__hdr_test(&s);
|
|
#else
|
|
STBI_NOTUSED(f);
|
|
return 0;
|
|
#endif
|
|
}
|
|
#endif // !STBI_NO_STDIO
|
|
|
|
STBIDEF int stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user)
|
|
{
|
|
#ifndef STBI_NO_HDR
|
|
stbi__context s;
|
|
stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
|
|
return stbi__hdr_test(&s);
|
|
#else
|
|
STBI_NOTUSED(clbk);
|
|
STBI_NOTUSED(user);
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
#ifndef STBI_NO_LINEAR
|
|
static float stbi__l2h_gamma=2.2f, stbi__l2h_scale=1.0f;
|
|
|
|
STBIDEF void stbi_ldr_to_hdr_gamma(float gamma) { stbi__l2h_gamma = gamma; }
|
|
STBIDEF void stbi_ldr_to_hdr_scale(float scale) { stbi__l2h_scale = scale; }
|
|
#endif
|
|
|
|
static float stbi__h2l_gamma_i=1.0f/2.2f, stbi__h2l_scale_i=1.0f;
|
|
|
|
STBIDEF void stbi_hdr_to_ldr_gamma(float gamma) { stbi__h2l_gamma_i = 1/gamma; }
|
|
STBIDEF void stbi_hdr_to_ldr_scale(float scale) { stbi__h2l_scale_i = 1/scale; }
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Common code used by all image loaders
|
|
//
|
|
|
|
enum
|
|
{
|
|
STBI__SCAN_load=0,
|
|
STBI__SCAN_type,
|
|
STBI__SCAN_header
|
|
};
|
|
|
|
static void stbi__refill_buffer(stbi__context *s)
|
|
{
|
|
int n = (s->io.read)(s->io_user_data,(char*)s->buffer_start,s->buflen);
|
|
if (n == 0) {
|
|
// at end of file, treat same as if from memory, but need to handle case
|
|
// where s->img_buffer isn't pointing to safe memory, e.g. 0-byte file
|
|
s->read_from_callbacks = 0;
|
|
s->img_buffer = s->buffer_start;
|
|
s->img_buffer_end = s->buffer_start+1;
|
|
*s->img_buffer = 0;
|
|
} else {
|
|
s->img_buffer = s->buffer_start;
|
|
s->img_buffer_end = s->buffer_start + n;
|
|
}
|
|
}
|
|
|
|
stbi_inline static stbi_uc stbi__get8(stbi__context *s)
|
|
{
|
|
if (s->img_buffer < s->img_buffer_end)
|
|
return *s->img_buffer++;
|
|
if (s->read_from_callbacks) {
|
|
stbi__refill_buffer(s);
|
|
return *s->img_buffer++;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
stbi_inline static int stbi__at_eof(stbi__context *s)
|
|
{
|
|
if (s->io.read) {
|
|
if (!(s->io.eof)(s->io_user_data)) return 0;
|
|
// if feof() is true, check if buffer = end
|
|
// special case: we've only got the special 0 character at the end
|
|
if (s->read_from_callbacks == 0) return 1;
|
|
}
|
|
|
|
return s->img_buffer >= s->img_buffer_end;
|
|
}
|
|
|
|
static void stbi__skip(stbi__context *s, int n)
|
|
{
|
|
if (n < 0) {
|
|
s->img_buffer = s->img_buffer_end;
|
|
return;
|
|
}
|
|
if (s->io.read) {
|
|
int blen = (int) (s->img_buffer_end - s->img_buffer);
|
|
if (blen < n) {
|
|
s->img_buffer = s->img_buffer_end;
|
|
(s->io.skip)(s->io_user_data, n - blen);
|
|
return;
|
|
}
|
|
}
|
|
s->img_buffer += n;
|
|
}
|
|
|
|
static int stbi__getn(stbi__context *s, stbi_uc *buffer, int n)
|
|
{
|
|
if (s->io.read) {
|
|
int blen = (int) (s->img_buffer_end - s->img_buffer);
|
|
if (blen < n) {
|
|
int res, count;
|
|
|
|
memcpy(buffer, s->img_buffer, blen);
|
|
|
|
count = (s->io.read)(s->io_user_data, (char*) buffer + blen, n - blen);
|
|
res = (count == (n-blen));
|
|
s->img_buffer = s->img_buffer_end;
|
|
return res;
|
|
}
|
|
}
|
|
|
|
if (s->img_buffer+n <= s->img_buffer_end) {
|
|
memcpy(buffer, s->img_buffer, n);
|
|
s->img_buffer += n;
|
|
return 1;
|
|
} else
|
|
return 0;
|
|
}
|
|
|
|
static int stbi__get16be(stbi__context *s)
|
|
{
|
|
int z = stbi__get8(s);
|
|
return (z << 8) + stbi__get8(s);
|
|
}
|
|
|
|
static stbi__uint32 stbi__get32be(stbi__context *s)
|
|
{
|
|
stbi__uint32 z = stbi__get16be(s);
|
|
return (z << 16) + stbi__get16be(s);
|
|
}
|
|
|
|
#if defined(STBI_NO_BMP) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF)
|
|
// nothing
|
|
#else
|
|
static int stbi__get16le(stbi__context *s)
|
|
{
|
|
int z = stbi__get8(s);
|
|
return z + (stbi__get8(s) << 8);
|
|
}
|
|
#endif
|
|
|
|
#ifndef STBI_NO_BMP
|
|
static stbi__uint32 stbi__get32le(stbi__context *s)
|
|
{
|
|
stbi__uint32 z = stbi__get16le(s);
|
|
return z + (stbi__get16le(s) << 16);
|
|
}
|
|
#endif
|
|
|
|
#define STBI__BYTECAST(x) ((stbi_uc) ((x) & 255)) // truncate int to byte without warnings
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// generic converter from built-in img_n to req_comp
|
|
// individual types do this automatically as much as possible (e.g. jpeg
|
|
// does all cases internally since it needs to colorspace convert anyway,
|
|
// and it never has alpha, so very few cases ). png can automatically
|
|
// interleave an alpha=255 channel, but falls back to this for other cases
|
|
//
|
|
// assume data buffer is malloced, so malloc a new one and free that one
|
|
// only failure mode is malloc failing
|
|
|
|
static stbi_uc stbi__compute_y(int r, int g, int b)
|
|
{
|
|
return (stbi_uc) (((r*77) + (g*150) + (29*b)) >> 8);
|
|
}
|
|
|
|
static unsigned char *stbi__convert_format(unsigned char *data, int img_n, int req_comp, unsigned int x, unsigned int y)
|
|
{
|
|
int i,j;
|
|
unsigned char *good;
|
|
|
|
if (req_comp == img_n) return data;
|
|
STBI_ASSERT(req_comp >= 1 && req_comp <= 4);
|
|
|
|
good = (unsigned char *) stbi__malloc(req_comp * x * y);
|
|
if (good == NULL) {
|
|
STBI_FREE(data);
|
|
return stbi__errpuc("outofmem", "Out of memory");
|
|
}
|
|
|
|
for (j=0; j < (int) y; ++j) {
|
|
unsigned char *src = data + j * x * img_n ;
|
|
unsigned char *dest = good + j * x * req_comp;
|
|
|
|
#define COMBO(a,b) ((a)*8+(b))
|
|
#define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
|
|
// convert source image with img_n components to one with req_comp components;
|
|
// avoid switch per pixel, so use switch per scanline and massive macros
|
|
switch (COMBO(img_n, req_comp)) {
|
|
CASE(1,2) dest[0]=src[0], dest[1]=255; break;
|
|
CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break;
|
|
CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break;
|
|
CASE(2,1) dest[0]=src[0]; break;
|
|
CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break;
|
|
CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break;
|
|
CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break;
|
|
CASE(3,1) dest[0]=stbi__compute_y(src[0],src[1],src[2]); break;
|
|
CASE(3,2) dest[0]=stbi__compute_y(src[0],src[1],src[2]), dest[1] = 255; break;
|
|
CASE(4,1) dest[0]=stbi__compute_y(src[0],src[1],src[2]); break;
|
|
CASE(4,2) dest[0]=stbi__compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break;
|
|
CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break;
|
|
default: STBI_ASSERT(0);
|
|
}
|
|
#undef CASE
|
|
}
|
|
|
|
STBI_FREE(data);
|
|
return good;
|
|
}
|
|
|
|
#ifndef STBI_NO_LINEAR
|
|
static float *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp)
|
|
{
|
|
int i,k,n;
|
|
float *output = (float *) stbi__malloc(x * y * comp * sizeof(float));
|
|
if (output == NULL) { STBI_FREE(data); return stbi__errpf("outofmem", "Out of memory"); }
|
|
// compute number of non-alpha components
|
|
if (comp & 1) n = comp; else n = comp-1;
|
|
for (i=0; i < x*y; ++i) {
|
|
for (k=0; k < n; ++k) {
|
|
output[i*comp + k] = (float) (pow(data[i*comp+k]/255.0f, stbi__l2h_gamma) * stbi__l2h_scale);
|
|
}
|
|
if (k < comp) output[i*comp + k] = data[i*comp+k]/255.0f;
|
|
}
|
|
STBI_FREE(data);
|
|
return output;
|
|
}
|
|
#endif
|
|
|
|
#ifndef STBI_NO_HDR
|
|
#define stbi__float2int(x) ((int) (x))
|
|
static stbi_uc *stbi__hdr_to_ldr(float *data, int x, int y, int comp)
|
|
{
|
|
int i,k,n;
|
|
stbi_uc *output = (stbi_uc *) stbi__malloc(x * y * comp);
|
|
if (output == NULL) { STBI_FREE(data); return stbi__errpuc("outofmem", "Out of memory"); }
|
|
// compute number of non-alpha components
|
|
if (comp & 1) n = comp; else n = comp-1;
|
|
for (i=0; i < x*y; ++i) {
|
|
for (k=0; k < n; ++k) {
|
|
float z = (float) pow(data[i*comp+k]*stbi__h2l_scale_i, stbi__h2l_gamma_i) * 255 + 0.5f;
|
|
if (z < 0) z = 0;
|
|
if (z > 255) z = 255;
|
|
output[i*comp + k] = (stbi_uc) stbi__float2int(z);
|
|
}
|
|
if (k < comp) {
|
|
float z = data[i*comp+k] * 255 + 0.5f;
|
|
if (z < 0) z = 0;
|
|
if (z > 255) z = 255;
|
|
output[i*comp + k] = (stbi_uc) stbi__float2int(z);
|
|
}
|
|
}
|
|
STBI_FREE(data);
|
|
return output;
|
|
}
|
|
#endif
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// "baseline" JPEG/JFIF decoder
|
|
//
|
|
// simple implementation
|
|
// - doesn't support delayed output of y-dimension
|
|
// - simple interface (only one output format: 8-bit interleaved RGB)
|
|
// - doesn't try to recover corrupt jpegs
|
|
// - doesn't allow partial loading, loading multiple at once
|
|
// - still fast on x86 (copying globals into locals doesn't help x86)
|
|
// - allocates lots of intermediate memory (full size of all components)
|
|
// - non-interleaved case requires this anyway
|
|
// - allows good upsampling (see next)
|
|
// high-quality
|
|
// - upsampled channels are bilinearly interpolated, even across blocks
|
|
// - quality integer IDCT derived from IJG's 'slow'
|
|
// performance
|
|
// - fast huffman; reasonable integer IDCT
|
|
// - some SIMD kernels for common paths on targets with SSE2/NEON
|
|
// - uses a lot of intermediate memory, could cache poorly
|
|
|
|
#ifndef STBI_NO_JPEG
|
|
|
|
// huffman decoding acceleration
|
|
#define FAST_BITS 9 // larger handles more cases; smaller stomps less cache
|
|
|
|
typedef struct
|
|
{
|
|
stbi_uc fast[1 << FAST_BITS];
|
|
// weirdly, repacking this into AoS is a 10% speed loss, instead of a win
|
|
stbi__uint16 code[256];
|
|
stbi_uc values[256];
|
|
stbi_uc size[257];
|
|
unsigned int maxcode[18];
|
|
int delta[17]; // old 'firstsymbol' - old 'firstcode'
|
|
} stbi__huffman;
|
|
|
|
typedef struct
|
|
{
|
|
stbi__context *s;
|
|
stbi__huffman huff_dc[4];
|
|
stbi__huffman huff_ac[4];
|
|
stbi_uc dequant[4][64];
|
|
stbi__int16 fast_ac[4][1 << FAST_BITS];
|
|
|
|
// sizes for components, interleaved MCUs
|
|
int img_h_max, img_v_max;
|
|
int img_mcu_x, img_mcu_y;
|
|
int img_mcu_w, img_mcu_h;
|
|
|
|
// definition of jpeg image component
|
|
struct
|
|
{
|
|
int id;
|
|
int h,v;
|
|
int tq;
|
|
int hd,ha;
|
|
int dc_pred;
|
|
|
|
int x,y,w2,h2;
|
|
stbi_uc *data;
|
|
void *raw_data, *raw_coeff;
|
|
stbi_uc *linebuf;
|
|
short *coeff; // progressive only
|
|
int coeff_w, coeff_h; // number of 8x8 coefficient blocks
|
|
} img_comp[4];
|
|
|
|
stbi__uint32 code_buffer; // jpeg entropy-coded buffer
|
|
int code_bits; // number of valid bits
|
|
unsigned char marker; // marker seen while filling entropy buffer
|
|
int nomore; // flag if we saw a marker so must stop
|
|
|
|
int progressive;
|
|
int spec_start;
|
|
int spec_end;
|
|
int succ_high;
|
|
int succ_low;
|
|
int eob_run;
|
|
int rgb;
|
|
|
|
int scan_n, order[4];
|
|
int restart_interval, todo;
|
|
|
|
// kernels
|
|
void (*idct_block_kernel)(stbi_uc *out, int out_stride, short data[64]);
|
|
void (*YCbCr_to_RGB_kernel)(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step);
|
|
stbi_uc *(*resample_row_hv_2_kernel)(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs);
|
|
} stbi__jpeg;
|
|
|
|
static int stbi__build_huffman(stbi__huffman *h, int *count)
|
|
{
|
|
int i,j,k=0,code;
|
|
// build size list for each symbol (from JPEG spec)
|
|
for (i=0; i < 16; ++i)
|
|
for (j=0; j < count[i]; ++j)
|
|
h->size[k++] = (stbi_uc) (i+1);
|
|
h->size[k] = 0;
|
|
|
|
// compute actual symbols (from jpeg spec)
|
|
code = 0;
|
|
k = 0;
|
|
for(j=1; j <= 16; ++j) {
|
|
// compute delta to add to code to compute symbol id
|
|
h->delta[j] = k - code;
|
|
if (h->size[k] == j) {
|
|
while (h->size[k] == j)
|
|
h->code[k++] = (stbi__uint16) (code++);
|
|
if (code-1 >= (1 << j)) return stbi__err("bad code lengths","Corrupt JPEG");
|
|
}
|
|
// compute largest code + 1 for this size, preshifted as needed later
|
|
h->maxcode[j] = code << (16-j);
|
|
code <<= 1;
|
|
}
|
|
h->maxcode[j] = 0xffffffff;
|
|
|
|
// build non-spec acceleration table; 255 is flag for not-accelerated
|
|
memset(h->fast, 255, 1 << FAST_BITS);
|
|
for (i=0; i < k; ++i) {
|
|
int s = h->size[i];
|
|
if (s <= FAST_BITS) {
|
|
int c = h->code[i] << (FAST_BITS-s);
|
|
int m = 1 << (FAST_BITS-s);
|
|
for (j=0; j < m; ++j) {
|
|
h->fast[c+j] = (stbi_uc) i;
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// build a table that decodes both magnitude and value of small ACs in
|
|
// one go.
|
|
static void stbi__build_fast_ac(stbi__int16 *fast_ac, stbi__huffman *h)
|
|
{
|
|
int i;
|
|
for (i=0; i < (1 << FAST_BITS); ++i) {
|
|
stbi_uc fast = h->fast[i];
|
|
fast_ac[i] = 0;
|
|
if (fast < 255) {
|
|
int rs = h->values[fast];
|
|
int run = (rs >> 4) & 15;
|
|
int magbits = rs & 15;
|
|
int len = h->size[fast];
|
|
|
|
if (magbits && len + magbits <= FAST_BITS) {
|
|
// magnitude code followed by receive_extend code
|
|
int k = ((i << len) & ((1 << FAST_BITS) - 1)) >> (FAST_BITS - magbits);
|
|
int m = 1 << (magbits - 1);
|
|
if (k < m) k += (-1 << magbits) + 1;
|
|
// if the result is small enough, we can fit it in fast_ac table
|
|
if (k >= -128 && k <= 127)
|
|
fast_ac[i] = (stbi__int16) ((k << 8) + (run << 4) + (len + magbits));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void stbi__grow_buffer_unsafe(stbi__jpeg *j)
|
|
{
|
|
do {
|
|
int b = j->nomore ? 0 : stbi__get8(j->s);
|
|
if (b == 0xff) {
|
|
int c = stbi__get8(j->s);
|
|
if (c != 0) {
|
|
j->marker = (unsigned char) c;
|
|
j->nomore = 1;
|
|
return;
|
|
}
|
|
}
|
|
j->code_buffer |= b << (24 - j->code_bits);
|
|
j->code_bits += 8;
|
|
} while (j->code_bits <= 24);
|
|
}
|
|
|
|
// (1 << n) - 1
|
|
static stbi__uint32 stbi__bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535};
|
|
|
|
// decode a jpeg huffman value from the bitstream
|
|
stbi_inline static int stbi__jpeg_huff_decode(stbi__jpeg *j, stbi__huffman *h)
|
|
{
|
|
unsigned int temp;
|
|
int c,k;
|
|
|
|
if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
|
|
|
|
// look at the top FAST_BITS and determine what symbol ID it is,
|
|
// if the code is <= FAST_BITS
|
|
c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
|
|
k = h->fast[c];
|
|
if (k < 255) {
|
|
int s = h->size[k];
|
|
if (s > j->code_bits)
|
|
return -1;
|
|
j->code_buffer <<= s;
|
|
j->code_bits -= s;
|
|
return h->values[k];
|
|
}
|
|
|
|
// naive test is to shift the code_buffer down so k bits are
|
|
// valid, then test against maxcode. To speed this up, we've
|
|
// preshifted maxcode left so that it has (16-k) 0s at the
|
|
// end; in other words, regardless of the number of bits, it
|
|
// wants to be compared against something shifted to have 16;
|
|
// that way we don't need to shift inside the loop.
|
|
temp = j->code_buffer >> 16;
|
|
for (k=FAST_BITS+1 ; ; ++k)
|
|
if (temp < h->maxcode[k])
|
|
break;
|
|
if (k == 17) {
|
|
// error! code not found
|
|
j->code_bits -= 16;
|
|
return -1;
|
|
}
|
|
|
|
if (k > j->code_bits)
|
|
return -1;
|
|
|
|
// convert the huffman code to the symbol id
|
|
c = ((j->code_buffer >> (32 - k)) & stbi__bmask[k]) + h->delta[k];
|
|
STBI_ASSERT((((j->code_buffer) >> (32 - h->size[c])) & stbi__bmask[h->size[c]]) == h->code[c]);
|
|
|
|
// convert the id to a symbol
|
|
j->code_bits -= k;
|
|
j->code_buffer <<= k;
|
|
return h->values[c];
|
|
}
|
|
|
|
// bias[n] = (-1<<n) + 1
|
|
static int const stbi__jbias[16] = {0,-1,-3,-7,-15,-31,-63,-127,-255,-511,-1023,-2047,-4095,-8191,-16383,-32767};
|
|
|
|
// combined JPEG 'receive' and JPEG 'extend', since baseline
|
|
// always extends everything it receives.
|
|
stbi_inline static int stbi__extend_receive(stbi__jpeg *j, int n)
|
|
{
|
|
unsigned int k;
|
|
int sgn;
|
|
if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
|
|
|
|
sgn = (stbi__int32)j->code_buffer >> 31; // sign bit is always in MSB
|
|
k = stbi_lrot(j->code_buffer, n);
|
|
STBI_ASSERT(n >= 0 && n < (int) (sizeof(stbi__bmask)/sizeof(*stbi__bmask)));
|
|
j->code_buffer = k & ~stbi__bmask[n];
|
|
k &= stbi__bmask[n];
|
|
j->code_bits -= n;
|
|
return k + (stbi__jbias[n] & ~sgn);
|
|
}
|
|
|
|
// get some unsigned bits
|
|
stbi_inline static int stbi__jpeg_get_bits(stbi__jpeg *j, int n)
|
|
{
|
|
unsigned int k;
|
|
if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
|
|
k = stbi_lrot(j->code_buffer, n);
|
|
j->code_buffer = k & ~stbi__bmask[n];
|
|
k &= stbi__bmask[n];
|
|
j->code_bits -= n;
|
|
return k;
|
|
}
|
|
|
|
stbi_inline static int stbi__jpeg_get_bit(stbi__jpeg *j)
|
|
{
|
|
unsigned int k;
|
|
if (j->code_bits < 1) stbi__grow_buffer_unsafe(j);
|
|
k = j->code_buffer;
|
|
j->code_buffer <<= 1;
|
|
--j->code_bits;
|
|
return k & 0x80000000;
|
|
}
|
|
|
|
// given a value that's at position X in the zigzag stream,
|
|
// where does it appear in the 8x8 matrix coded as row-major?
|
|
static stbi_uc stbi__jpeg_dezigzag[64+15] =
|
|
{
|
|
0, 1, 8, 16, 9, 2, 3, 10,
|
|
17, 24, 32, 25, 18, 11, 4, 5,
|
|
12, 19, 26, 33, 40, 48, 41, 34,
|
|
27, 20, 13, 6, 7, 14, 21, 28,
|
|
35, 42, 49, 56, 57, 50, 43, 36,
|
|
29, 22, 15, 23, 30, 37, 44, 51,
|
|
58, 59, 52, 45, 38, 31, 39, 46,
|
|
53, 60, 61, 54, 47, 55, 62, 63,
|
|
// let corrupt input sample past end
|
|
63, 63, 63, 63, 63, 63, 63, 63,
|
|
63, 63, 63, 63, 63, 63, 63
|
|
};
|
|
|
|
// decode one 64-entry block--
|
|
static int stbi__jpeg_decode_block(stbi__jpeg *j, short data[64], stbi__huffman *hdc, stbi__huffman *hac, stbi__int16 *fac, int b, stbi_uc *dequant)
|
|
{
|
|
int diff,dc,k;
|
|
int t;
|
|
|
|
if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
|
|
t = stbi__jpeg_huff_decode(j, hdc);
|
|
if (t < 0) return stbi__err("bad huffman code","Corrupt JPEG");
|
|
|
|
// 0 all the ac values now so we can do it 32-bits at a time
|
|
memset(data,0,64*sizeof(data[0]));
|
|
|
|
diff = t ? stbi__extend_receive(j, t) : 0;
|
|
dc = j->img_comp[b].dc_pred + diff;
|
|
j->img_comp[b].dc_pred = dc;
|
|
data[0] = (short) (dc * dequant[0]);
|
|
|
|
// decode AC components, see JPEG spec
|
|
k = 1;
|
|
do {
|
|
unsigned int zig;
|
|
int c,r,s;
|
|
if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
|
|
c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
|
|
r = fac[c];
|
|
if (r) { // fast-AC path
|
|
k += (r >> 4) & 15; // run
|
|
s = r & 15; // combined length
|
|
j->code_buffer <<= s;
|
|
j->code_bits -= s;
|
|
// decode into unzigzag'd location
|
|
zig = stbi__jpeg_dezigzag[k++];
|
|
data[zig] = (short) ((r >> 8) * dequant[zig]);
|
|
} else {
|
|
int rs = stbi__jpeg_huff_decode(j, hac);
|
|
if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
|
|
s = rs & 15;
|
|
r = rs >> 4;
|
|
if (s == 0) {
|
|
if (rs != 0xf0) break; // end block
|
|
k += 16;
|
|
} else {
|
|
k += r;
|
|
// decode into unzigzag'd location
|
|
zig = stbi__jpeg_dezigzag[k++];
|
|
data[zig] = (short) (stbi__extend_receive(j,s) * dequant[zig]);
|
|
}
|
|
}
|
|
} while (k < 64);
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__jpeg_decode_block_prog_dc(stbi__jpeg *j, short data[64], stbi__huffman *hdc, int b)
|
|
{
|
|
int diff,dc;
|
|
int t;
|
|
if (j->spec_end != 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
|
|
|
|
if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
|
|
|
|
if (j->succ_high == 0) {
|
|
// first scan for DC coefficient, must be first
|
|
memset(data,0,64*sizeof(data[0])); // 0 all the ac values now
|
|
t = stbi__jpeg_huff_decode(j, hdc);
|
|
diff = t ? stbi__extend_receive(j, t) : 0;
|
|
|
|
dc = j->img_comp[b].dc_pred + diff;
|
|
j->img_comp[b].dc_pred = dc;
|
|
data[0] = (short) (dc << j->succ_low);
|
|
} else {
|
|
// refinement scan for DC coefficient
|
|
if (stbi__jpeg_get_bit(j))
|
|
data[0] += (short) (1 << j->succ_low);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// @OPTIMIZE: store non-zigzagged during the decode passes,
|
|
// and only de-zigzag when dequantizing
|
|
static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__huffman *hac, stbi__int16 *fac)
|
|
{
|
|
int k;
|
|
if (j->spec_start == 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
|
|
|
|
if (j->succ_high == 0) {
|
|
int shift = j->succ_low;
|
|
|
|
if (j->eob_run) {
|
|
--j->eob_run;
|
|
return 1;
|
|
}
|
|
|
|
k = j->spec_start;
|
|
do {
|
|
unsigned int zig;
|
|
int c,r,s;
|
|
if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
|
|
c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
|
|
r = fac[c];
|
|
if (r) { // fast-AC path
|
|
k += (r >> 4) & 15; // run
|
|
s = r & 15; // combined length
|
|
j->code_buffer <<= s;
|
|
j->code_bits -= s;
|
|
zig = stbi__jpeg_dezigzag[k++];
|
|
data[zig] = (short) ((r >> 8) << shift);
|
|
} else {
|
|
int rs = stbi__jpeg_huff_decode(j, hac);
|
|
if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
|
|
s = rs & 15;
|
|
r = rs >> 4;
|
|
if (s == 0) {
|
|
if (r < 15) {
|
|
j->eob_run = (1 << r);
|
|
if (r)
|
|
j->eob_run += stbi__jpeg_get_bits(j, r);
|
|
--j->eob_run;
|
|
break;
|
|
}
|
|
k += 16;
|
|
} else {
|
|
k += r;
|
|
zig = stbi__jpeg_dezigzag[k++];
|
|
data[zig] = (short) (stbi__extend_receive(j,s) << shift);
|
|
}
|
|
}
|
|
} while (k <= j->spec_end);
|
|
} else {
|
|
// refinement scan for these AC coefficients
|
|
|
|
short bit = (short) (1 << j->succ_low);
|
|
|
|
if (j->eob_run) {
|
|
--j->eob_run;
|
|
for (k = j->spec_start; k <= j->spec_end; ++k) {
|
|
short *p = &data[stbi__jpeg_dezigzag[k]];
|
|
if (*p != 0)
|
|
if (stbi__jpeg_get_bit(j))
|
|
if ((*p & bit)==0) {
|
|
if (*p > 0)
|
|
*p += bit;
|
|
else
|
|
*p -= bit;
|
|
}
|
|
}
|
|
} else {
|
|
k = j->spec_start;
|
|
do {
|
|
int r,s;
|
|
int rs = stbi__jpeg_huff_decode(j, hac); // @OPTIMIZE see if we can use the fast path here, advance-by-r is so slow, eh
|
|
if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
|
|
s = rs & 15;
|
|
r = rs >> 4;
|
|
if (s == 0) {
|
|
if (r < 15) {
|
|
j->eob_run = (1 << r) - 1;
|
|
if (r)
|
|
j->eob_run += stbi__jpeg_get_bits(j, r);
|
|
r = 64; // force end of block
|
|
} else {
|
|
// r=15 s=0 should write 16 0s, so we just do
|
|
// a run of 15 0s and then write s (which is 0),
|
|
// so we don't have to do anything special here
|
|
}
|
|
} else {
|
|
if (s != 1) return stbi__err("bad huffman code", "Corrupt JPEG");
|
|
// sign bit
|
|
if (stbi__jpeg_get_bit(j))
|
|
s = bit;
|
|
else
|
|
s = -bit;
|
|
}
|
|
|
|
// advance by r
|
|
while (k <= j->spec_end) {
|
|
short *p = &data[stbi__jpeg_dezigzag[k++]];
|
|
if (*p != 0) {
|
|
if (stbi__jpeg_get_bit(j))
|
|
if ((*p & bit)==0) {
|
|
if (*p > 0)
|
|
*p += bit;
|
|
else
|
|
*p -= bit;
|
|
}
|
|
} else {
|
|
if (r == 0) {
|
|
*p = (short) s;
|
|
break;
|
|
}
|
|
--r;
|
|
}
|
|
}
|
|
} while (k <= j->spec_end);
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// take a -128..127 value and stbi__clamp it and convert to 0..255
|
|
stbi_inline static stbi_uc stbi__clamp(int x)
|
|
{
|
|
// trick to use a single test to catch both cases
|
|
if ((unsigned int) x > 255) {
|
|
if (x < 0) return 0;
|
|
if (x > 255) return 255;
|
|
}
|
|
return (stbi_uc) x;
|
|
}
|
|
|
|
#define stbi__f2f(x) ((int) (((x) * 4096 + 0.5)))
|
|
#define stbi__fsh(x) ((x) << 12)
|
|
|
|
// derived from jidctint -- DCT_ISLOW
|
|
#define STBI__IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \
|
|
int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \
|
|
p2 = s2; \
|
|
p3 = s6; \
|
|
p1 = (p2+p3) * stbi__f2f(0.5411961f); \
|
|
t2 = p1 + p3*stbi__f2f(-1.847759065f); \
|
|
t3 = p1 + p2*stbi__f2f( 0.765366865f); \
|
|
p2 = s0; \
|
|
p3 = s4; \
|
|
t0 = stbi__fsh(p2+p3); \
|
|
t1 = stbi__fsh(p2-p3); \
|
|
x0 = t0+t3; \
|
|
x3 = t0-t3; \
|
|
x1 = t1+t2; \
|
|
x2 = t1-t2; \
|
|
t0 = s7; \
|
|
t1 = s5; \
|
|
t2 = s3; \
|
|
t3 = s1; \
|
|
p3 = t0+t2; \
|
|
p4 = t1+t3; \
|
|
p1 = t0+t3; \
|
|
p2 = t1+t2; \
|
|
p5 = (p3+p4)*stbi__f2f( 1.175875602f); \
|
|
t0 = t0*stbi__f2f( 0.298631336f); \
|
|
t1 = t1*stbi__f2f( 2.053119869f); \
|
|
t2 = t2*stbi__f2f( 3.072711026f); \
|
|
t3 = t3*stbi__f2f( 1.501321110f); \
|
|
p1 = p5 + p1*stbi__f2f(-0.899976223f); \
|
|
p2 = p5 + p2*stbi__f2f(-2.562915447f); \
|
|
p3 = p3*stbi__f2f(-1.961570560f); \
|
|
p4 = p4*stbi__f2f(-0.390180644f); \
|
|
t3 += p1+p4; \
|
|
t2 += p2+p3; \
|
|
t1 += p2+p4; \
|
|
t0 += p1+p3;
|
|
|
|
static void stbi__idct_block(stbi_uc *out, int out_stride, short data[64])
|
|
{
|
|
int i,val[64],*v=val;
|
|
stbi_uc *o;
|
|
short *d = data;
|
|
|
|
// columns
|
|
for (i=0; i < 8; ++i,++d, ++v) {
|
|
// if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing
|
|
if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0
|
|
&& d[40]==0 && d[48]==0 && d[56]==0) {
|
|
// no shortcut 0 seconds
|
|
// (1|2|3|4|5|6|7)==0 0 seconds
|
|
// all separate -0.047 seconds
|
|
// 1 && 2|3 && 4|5 && 6|7: -0.047 seconds
|
|
int dcterm = d[0] << 2;
|
|
v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm;
|
|
} else {
|
|
STBI__IDCT_1D(d[ 0],d[ 8],d[16],d[24],d[32],d[40],d[48],d[56])
|
|
// constants scaled things up by 1<<12; let's bring them back
|
|
// down, but keep 2 extra bits of precision
|
|
x0 += 512; x1 += 512; x2 += 512; x3 += 512;
|
|
v[ 0] = (x0+t3) >> 10;
|
|
v[56] = (x0-t3) >> 10;
|
|
v[ 8] = (x1+t2) >> 10;
|
|
v[48] = (x1-t2) >> 10;
|
|
v[16] = (x2+t1) >> 10;
|
|
v[40] = (x2-t1) >> 10;
|
|
v[24] = (x3+t0) >> 10;
|
|
v[32] = (x3-t0) >> 10;
|
|
}
|
|
}
|
|
|
|
for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) {
|
|
// no fast case since the first 1D IDCT spread components out
|
|
STBI__IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7])
|
|
// constants scaled things up by 1<<12, plus we had 1<<2 from first
|
|
// loop, plus horizontal and vertical each scale by sqrt(8) so together
|
|
// we've got an extra 1<<3, so 1<<17 total we need to remove.
|
|
// so we want to round that, which means adding 0.5 * 1<<17,
|
|
// aka 65536. Also, we'll end up with -128 to 127 that we want
|
|
// to encode as 0..255 by adding 128, so we'll add that before the shift
|
|
x0 += 65536 + (128<<17);
|
|
x1 += 65536 + (128<<17);
|
|
x2 += 65536 + (128<<17);
|
|
x3 += 65536 + (128<<17);
|
|
// tried computing the shifts into temps, or'ing the temps to see
|
|
// if any were out of range, but that was slower
|
|
o[0] = stbi__clamp((x0+t3) >> 17);
|
|
o[7] = stbi__clamp((x0-t3) >> 17);
|
|
o[1] = stbi__clamp((x1+t2) >> 17);
|
|
o[6] = stbi__clamp((x1-t2) >> 17);
|
|
o[2] = stbi__clamp((x2+t1) >> 17);
|
|
o[5] = stbi__clamp((x2-t1) >> 17);
|
|
o[3] = stbi__clamp((x3+t0) >> 17);
|
|
o[4] = stbi__clamp((x3-t0) >> 17);
|
|
}
|
|
}
|
|
|
|
#ifdef STBI_SSE2
|
|
// sse2 integer IDCT. not the fastest possible implementation but it
|
|
// produces bit-identical results to the generic C version so it's
|
|
// fully "transparent".
|
|
static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64])
|
|
{
|
|
// This is constructed to match our regular (generic) integer IDCT exactly.
|
|
__m128i row0, row1, row2, row3, row4, row5, row6, row7;
|
|
__m128i tmp;
|
|
|
|
// dot product constant: even elems=x, odd elems=y
|
|
#define dct_const(x,y) _mm_setr_epi16((x),(y),(x),(y),(x),(y),(x),(y))
|
|
|
|
// out(0) = c0[even]*x + c0[odd]*y (c0, x, y 16-bit, out 32-bit)
|
|
// out(1) = c1[even]*x + c1[odd]*y
|
|
#define dct_rot(out0,out1, x,y,c0,c1) \
|
|
__m128i c0##lo = _mm_unpacklo_epi16((x),(y)); \
|
|
__m128i c0##hi = _mm_unpackhi_epi16((x),(y)); \
|
|
__m128i out0##_l = _mm_madd_epi16(c0##lo, c0); \
|
|
__m128i out0##_h = _mm_madd_epi16(c0##hi, c0); \
|
|
__m128i out1##_l = _mm_madd_epi16(c0##lo, c1); \
|
|
__m128i out1##_h = _mm_madd_epi16(c0##hi, c1)
|
|
|
|
// out = in << 12 (in 16-bit, out 32-bit)
|
|
#define dct_widen(out, in) \
|
|
__m128i out##_l = _mm_srai_epi32(_mm_unpacklo_epi16(_mm_setzero_si128(), (in)), 4); \
|
|
__m128i out##_h = _mm_srai_epi32(_mm_unpackhi_epi16(_mm_setzero_si128(), (in)), 4)
|
|
|
|
// wide add
|
|
#define dct_wadd(out, a, b) \
|
|
__m128i out##_l = _mm_add_epi32(a##_l, b##_l); \
|
|
__m128i out##_h = _mm_add_epi32(a##_h, b##_h)
|
|
|
|
// wide sub
|
|
#define dct_wsub(out, a, b) \
|
|
__m128i out##_l = _mm_sub_epi32(a##_l, b##_l); \
|
|
__m128i out##_h = _mm_sub_epi32(a##_h, b##_h)
|
|
|
|
// butterfly a/b, add bias, then shift by "s" and pack
|
|
#define dct_bfly32o(out0, out1, a,b,bias,s) \
|
|
{ \
|
|
__m128i abiased_l = _mm_add_epi32(a##_l, bias); \
|
|
__m128i abiased_h = _mm_add_epi32(a##_h, bias); \
|
|
dct_wadd(sum, abiased, b); \
|
|
dct_wsub(dif, abiased, b); \
|
|
out0 = _mm_packs_epi32(_mm_srai_epi32(sum_l, s), _mm_srai_epi32(sum_h, s)); \
|
|
out1 = _mm_packs_epi32(_mm_srai_epi32(dif_l, s), _mm_srai_epi32(dif_h, s)); \
|
|
}
|
|
|
|
// 8-bit interleave step (for transposes)
|
|
#define dct_interleave8(a, b) \
|
|
tmp = a; \
|
|
a = _mm_unpacklo_epi8(a, b); \
|
|
b = _mm_unpackhi_epi8(tmp, b)
|
|
|
|
// 16-bit interleave step (for transposes)
|
|
#define dct_interleave16(a, b) \
|
|
tmp = a; \
|
|
a = _mm_unpacklo_epi16(a, b); \
|
|
b = _mm_unpackhi_epi16(tmp, b)
|
|
|
|
#define dct_pass(bias,shift) \
|
|
{ \
|
|
/* even part */ \
|
|
dct_rot(t2e,t3e, row2,row6, rot0_0,rot0_1); \
|
|
__m128i sum04 = _mm_add_epi16(row0, row4); \
|
|
__m128i dif04 = _mm_sub_epi16(row0, row4); \
|
|
dct_widen(t0e, sum04); \
|
|
dct_widen(t1e, dif04); \
|
|
dct_wadd(x0, t0e, t3e); \
|
|
dct_wsub(x3, t0e, t3e); \
|
|
dct_wadd(x1, t1e, t2e); \
|
|
dct_wsub(x2, t1e, t2e); \
|
|
/* odd part */ \
|
|
dct_rot(y0o,y2o, row7,row3, rot2_0,rot2_1); \
|
|
dct_rot(y1o,y3o, row5,row1, rot3_0,rot3_1); \
|
|
__m128i sum17 = _mm_add_epi16(row1, row7); \
|
|
__m128i sum35 = _mm_add_epi16(row3, row5); \
|
|
dct_rot(y4o,y5o, sum17,sum35, rot1_0,rot1_1); \
|
|
dct_wadd(x4, y0o, y4o); \
|
|
dct_wadd(x5, y1o, y5o); \
|
|
dct_wadd(x6, y2o, y5o); \
|
|
dct_wadd(x7, y3o, y4o); \
|
|
dct_bfly32o(row0,row7, x0,x7,bias,shift); \
|
|
dct_bfly32o(row1,row6, x1,x6,bias,shift); \
|
|
dct_bfly32o(row2,row5, x2,x5,bias,shift); \
|
|
dct_bfly32o(row3,row4, x3,x4,bias,shift); \
|
|
}
|
|
|
|
__m128i rot0_0 = dct_const(stbi__f2f(0.5411961f), stbi__f2f(0.5411961f) + stbi__f2f(-1.847759065f));
|
|
__m128i rot0_1 = dct_const(stbi__f2f(0.5411961f) + stbi__f2f( 0.765366865f), stbi__f2f(0.5411961f));
|
|
__m128i rot1_0 = dct_const(stbi__f2f(1.175875602f) + stbi__f2f(-0.899976223f), stbi__f2f(1.175875602f));
|
|
__m128i rot1_1 = dct_const(stbi__f2f(1.175875602f), stbi__f2f(1.175875602f) + stbi__f2f(-2.562915447f));
|
|
__m128i rot2_0 = dct_const(stbi__f2f(-1.961570560f) + stbi__f2f( 0.298631336f), stbi__f2f(-1.961570560f));
|
|
__m128i rot2_1 = dct_const(stbi__f2f(-1.961570560f), stbi__f2f(-1.961570560f) + stbi__f2f( 3.072711026f));
|
|
__m128i rot3_0 = dct_const(stbi__f2f(-0.390180644f) + stbi__f2f( 2.053119869f), stbi__f2f(-0.390180644f));
|
|
__m128i rot3_1 = dct_const(stbi__f2f(-0.390180644f), stbi__f2f(-0.390180644f) + stbi__f2f( 1.501321110f));
|
|
|
|
// rounding biases in column/row passes, see stbi__idct_block for explanation.
|
|
__m128i bias_0 = _mm_set1_epi32(512);
|
|
__m128i bias_1 = _mm_set1_epi32(65536 + (128<<17));
|
|
|
|
// load
|
|
row0 = _mm_load_si128((const __m128i *) (data + 0*8));
|
|
row1 = _mm_load_si128((const __m128i *) (data + 1*8));
|
|
row2 = _mm_load_si128((const __m128i *) (data + 2*8));
|
|
row3 = _mm_load_si128((const __m128i *) (data + 3*8));
|
|
row4 = _mm_load_si128((const __m128i *) (data + 4*8));
|
|
row5 = _mm_load_si128((const __m128i *) (data + 5*8));
|
|
row6 = _mm_load_si128((const __m128i *) (data + 6*8));
|
|
row7 = _mm_load_si128((const __m128i *) (data + 7*8));
|
|
|
|
// column pass
|
|
dct_pass(bias_0, 10);
|
|
|
|
{
|
|
// 16bit 8x8 transpose pass 1
|
|
dct_interleave16(row0, row4);
|
|
dct_interleave16(row1, row5);
|
|
dct_interleave16(row2, row6);
|
|
dct_interleave16(row3, row7);
|
|
|
|
// transpose pass 2
|
|
dct_interleave16(row0, row2);
|
|
dct_interleave16(row1, row3);
|
|
dct_interleave16(row4, row6);
|
|
dct_interleave16(row5, row7);
|
|
|
|
// transpose pass 3
|
|
dct_interleave16(row0, row1);
|
|
dct_interleave16(row2, row3);
|
|
dct_interleave16(row4, row5);
|
|
dct_interleave16(row6, row7);
|
|
}
|
|
|
|
// row pass
|
|
dct_pass(bias_1, 17);
|
|
|
|
{
|
|
// pack
|
|
__m128i p0 = _mm_packus_epi16(row0, row1); // a0a1a2a3...a7b0b1b2b3...b7
|
|
__m128i p1 = _mm_packus_epi16(row2, row3);
|
|
__m128i p2 = _mm_packus_epi16(row4, row5);
|
|
__m128i p3 = _mm_packus_epi16(row6, row7);
|
|
|
|
// 8bit 8x8 transpose pass 1
|
|
dct_interleave8(p0, p2); // a0e0a1e1...
|
|
dct_interleave8(p1, p3); // c0g0c1g1...
|
|
|
|
// transpose pass 2
|
|
dct_interleave8(p0, p1); // a0c0e0g0...
|
|
dct_interleave8(p2, p3); // b0d0f0h0...
|
|
|
|
// transpose pass 3
|
|
dct_interleave8(p0, p2); // a0b0c0d0...
|
|
dct_interleave8(p1, p3); // a4b4c4d4...
|
|
|
|
// store
|
|
_mm_storel_epi64((__m128i *) out, p0); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p0, 0x4e)); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, p2); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p2, 0x4e)); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, p1); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p1, 0x4e)); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, p3); out += out_stride;
|
|
_mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p3, 0x4e));
|
|
}
|
|
|
|
#undef dct_const
|
|
#undef dct_rot
|
|
#undef dct_widen
|
|
#undef dct_wadd
|
|
#undef dct_wsub
|
|
#undef dct_bfly32o
|
|
#undef dct_interleave8
|
|
#undef dct_interleave16
|
|
#undef dct_pass
|
|
}
|
|
|
|
#endif // STBI_SSE2
|
|
|
|
#ifdef STBI_NEON
|
|
|
|
// NEON integer IDCT. should produce bit-identical
|
|
// results to the generic C version.
|
|
static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64])
|
|
{
|
|
int16x8_t row0, row1, row2, row3, row4, row5, row6, row7;
|
|
|
|
int16x4_t rot0_0 = vdup_n_s16(stbi__f2f(0.5411961f));
|
|
int16x4_t rot0_1 = vdup_n_s16(stbi__f2f(-1.847759065f));
|
|
int16x4_t rot0_2 = vdup_n_s16(stbi__f2f( 0.765366865f));
|
|
int16x4_t rot1_0 = vdup_n_s16(stbi__f2f( 1.175875602f));
|
|
int16x4_t rot1_1 = vdup_n_s16(stbi__f2f(-0.899976223f));
|
|
int16x4_t rot1_2 = vdup_n_s16(stbi__f2f(-2.562915447f));
|
|
int16x4_t rot2_0 = vdup_n_s16(stbi__f2f(-1.961570560f));
|
|
int16x4_t rot2_1 = vdup_n_s16(stbi__f2f(-0.390180644f));
|
|
int16x4_t rot3_0 = vdup_n_s16(stbi__f2f( 0.298631336f));
|
|
int16x4_t rot3_1 = vdup_n_s16(stbi__f2f( 2.053119869f));
|
|
int16x4_t rot3_2 = vdup_n_s16(stbi__f2f( 3.072711026f));
|
|
int16x4_t rot3_3 = vdup_n_s16(stbi__f2f( 1.501321110f));
|
|
|
|
#define dct_long_mul(out, inq, coeff) \
|
|
int32x4_t out##_l = vmull_s16(vget_low_s16(inq), coeff); \
|
|
int32x4_t out##_h = vmull_s16(vget_high_s16(inq), coeff)
|
|
|
|
#define dct_long_mac(out, acc, inq, coeff) \
|
|
int32x4_t out##_l = vmlal_s16(acc##_l, vget_low_s16(inq), coeff); \
|
|
int32x4_t out##_h = vmlal_s16(acc##_h, vget_high_s16(inq), coeff)
|
|
|
|
#define dct_widen(out, inq) \
|
|
int32x4_t out##_l = vshll_n_s16(vget_low_s16(inq), 12); \
|
|
int32x4_t out##_h = vshll_n_s16(vget_high_s16(inq), 12)
|
|
|
|
// wide add
|
|
#define dct_wadd(out, a, b) \
|
|
int32x4_t out##_l = vaddq_s32(a##_l, b##_l); \
|
|
int32x4_t out##_h = vaddq_s32(a##_h, b##_h)
|
|
|
|
// wide sub
|
|
#define dct_wsub(out, a, b) \
|
|
int32x4_t out##_l = vsubq_s32(a##_l, b##_l); \
|
|
int32x4_t out##_h = vsubq_s32(a##_h, b##_h)
|
|
|
|
// butterfly a/b, then shift using "shiftop" by "s" and pack
|
|
#define dct_bfly32o(out0,out1, a,b,shiftop,s) \
|
|
{ \
|
|
dct_wadd(sum, a, b); \
|
|
dct_wsub(dif, a, b); \
|
|
out0 = vcombine_s16(shiftop(sum_l, s), shiftop(sum_h, s)); \
|
|
out1 = vcombine_s16(shiftop(dif_l, s), shiftop(dif_h, s)); \
|
|
}
|
|
|
|
#define dct_pass(shiftop, shift) \
|
|
{ \
|
|
/* even part */ \
|
|
int16x8_t sum26 = vaddq_s16(row2, row6); \
|
|
dct_long_mul(p1e, sum26, rot0_0); \
|
|
dct_long_mac(t2e, p1e, row6, rot0_1); \
|
|
dct_long_mac(t3e, p1e, row2, rot0_2); \
|
|
int16x8_t sum04 = vaddq_s16(row0, row4); \
|
|
int16x8_t dif04 = vsubq_s16(row0, row4); \
|
|
dct_widen(t0e, sum04); \
|
|
dct_widen(t1e, dif04); \
|
|
dct_wadd(x0, t0e, t3e); \
|
|
dct_wsub(x3, t0e, t3e); \
|
|
dct_wadd(x1, t1e, t2e); \
|
|
dct_wsub(x2, t1e, t2e); \
|
|
/* odd part */ \
|
|
int16x8_t sum15 = vaddq_s16(row1, row5); \
|
|
int16x8_t sum17 = vaddq_s16(row1, row7); \
|
|
int16x8_t sum35 = vaddq_s16(row3, row5); \
|
|
int16x8_t sum37 = vaddq_s16(row3, row7); \
|
|
int16x8_t sumodd = vaddq_s16(sum17, sum35); \
|
|
dct_long_mul(p5o, sumodd, rot1_0); \
|
|
dct_long_mac(p1o, p5o, sum17, rot1_1); \
|
|
dct_long_mac(p2o, p5o, sum35, rot1_2); \
|
|
dct_long_mul(p3o, sum37, rot2_0); \
|
|
dct_long_mul(p4o, sum15, rot2_1); \
|
|
dct_wadd(sump13o, p1o, p3o); \
|
|
dct_wadd(sump24o, p2o, p4o); \
|
|
dct_wadd(sump23o, p2o, p3o); \
|
|
dct_wadd(sump14o, p1o, p4o); \
|
|
dct_long_mac(x4, sump13o, row7, rot3_0); \
|
|
dct_long_mac(x5, sump24o, row5, rot3_1); \
|
|
dct_long_mac(x6, sump23o, row3, rot3_2); \
|
|
dct_long_mac(x7, sump14o, row1, rot3_3); \
|
|
dct_bfly32o(row0,row7, x0,x7,shiftop,shift); \
|
|
dct_bfly32o(row1,row6, x1,x6,shiftop,shift); \
|
|
dct_bfly32o(row2,row5, x2,x5,shiftop,shift); \
|
|
dct_bfly32o(row3,row4, x3,x4,shiftop,shift); \
|
|
}
|
|
|
|
// load
|
|
row0 = vld1q_s16(data + 0*8);
|
|
row1 = vld1q_s16(data + 1*8);
|
|
row2 = vld1q_s16(data + 2*8);
|
|
row3 = vld1q_s16(data + 3*8);
|
|
row4 = vld1q_s16(data + 4*8);
|
|
row5 = vld1q_s16(data + 5*8);
|
|
row6 = vld1q_s16(data + 6*8);
|
|
row7 = vld1q_s16(data + 7*8);
|
|
|
|
// add DC bias
|
|
row0 = vaddq_s16(row0, vsetq_lane_s16(1024, vdupq_n_s16(0), 0));
|
|
|
|
// column pass
|
|
dct_pass(vrshrn_n_s32, 10);
|
|
|
|
// 16bit 8x8 transpose
|
|
{
|
|
// these three map to a single VTRN.16, VTRN.32, and VSWP, respectively.
|
|
// whether compilers actually get this is another story, sadly.
|
|
#define dct_trn16(x, y) { int16x8x2_t t = vtrnq_s16(x, y); x = t.val[0]; y = t.val[1]; }
|
|
#define dct_trn32(x, y) { int32x4x2_t t = vtrnq_s32(vreinterpretq_s32_s16(x), vreinterpretq_s32_s16(y)); x = vreinterpretq_s16_s32(t.val[0]); y = vreinterpretq_s16_s32(t.val[1]); }
|
|
#define dct_trn64(x, y) { int16x8_t x0 = x; int16x8_t y0 = y; x = vcombine_s16(vget_low_s16(x0), vget_low_s16(y0)); y = vcombine_s16(vget_high_s16(x0), vget_high_s16(y0)); }
|
|
|
|
// pass 1
|
|
dct_trn16(row0, row1); // a0b0a2b2a4b4a6b6
|
|
dct_trn16(row2, row3);
|
|
dct_trn16(row4, row5);
|
|
dct_trn16(row6, row7);
|
|
|
|
// pass 2
|
|
dct_trn32(row0, row2); // a0b0c0d0a4b4c4d4
|
|
dct_trn32(row1, row3);
|
|
dct_trn32(row4, row6);
|
|
dct_trn32(row5, row7);
|
|
|
|
// pass 3
|
|
dct_trn64(row0, row4); // a0b0c0d0e0f0g0h0
|
|
dct_trn64(row1, row5);
|
|
dct_trn64(row2, row6);
|
|
dct_trn64(row3, row7);
|
|
|
|
#undef dct_trn16
|
|
#undef dct_trn32
|
|
#undef dct_trn64
|
|
}
|
|
|
|
// row pass
|
|
// vrshrn_n_s32 only supports shifts up to 16, we need
|
|
// 17. so do a non-rounding shift of 16 first then follow
|
|
// up with a rounding shift by 1.
|
|
dct_pass(vshrn_n_s32, 16);
|
|
|
|
{
|
|
// pack and round
|
|
uint8x8_t p0 = vqrshrun_n_s16(row0, 1);
|
|
uint8x8_t p1 = vqrshrun_n_s16(row1, 1);
|
|
uint8x8_t p2 = vqrshrun_n_s16(row2, 1);
|
|
uint8x8_t p3 = vqrshrun_n_s16(row3, 1);
|
|
uint8x8_t p4 = vqrshrun_n_s16(row4, 1);
|
|
uint8x8_t p5 = vqrshrun_n_s16(row5, 1);
|
|
uint8x8_t p6 = vqrshrun_n_s16(row6, 1);
|
|
uint8x8_t p7 = vqrshrun_n_s16(row7, 1);
|
|
|
|
// again, these can translate into one instruction, but often don't.
|
|
#define dct_trn8_8(x, y) { uint8x8x2_t t = vtrn_u8(x, y); x = t.val[0]; y = t.val[1]; }
|
|
#define dct_trn8_16(x, y) { uint16x4x2_t t = vtrn_u16(vreinterpret_u16_u8(x), vreinterpret_u16_u8(y)); x = vreinterpret_u8_u16(t.val[0]); y = vreinterpret_u8_u16(t.val[1]); }
|
|
#define dct_trn8_32(x, y) { uint32x2x2_t t = vtrn_u32(vreinterpret_u32_u8(x), vreinterpret_u32_u8(y)); x = vreinterpret_u8_u32(t.val[0]); y = vreinterpret_u8_u32(t.val[1]); }
|
|
|
|
// sadly can't use interleaved stores here since we only write
|
|
// 8 bytes to each scan line!
|
|
|
|
// 8x8 8-bit transpose pass 1
|
|
dct_trn8_8(p0, p1);
|
|
dct_trn8_8(p2, p3);
|
|
dct_trn8_8(p4, p5);
|
|
dct_trn8_8(p6, p7);
|
|
|
|
// pass 2
|
|
dct_trn8_16(p0, p2);
|
|
dct_trn8_16(p1, p3);
|
|
dct_trn8_16(p4, p6);
|
|
dct_trn8_16(p5, p7);
|
|
|
|
// pass 3
|
|
dct_trn8_32(p0, p4);
|
|
dct_trn8_32(p1, p5);
|
|
dct_trn8_32(p2, p6);
|
|
dct_trn8_32(p3, p7);
|
|
|
|
// store
|
|
vst1_u8(out, p0); out += out_stride;
|
|
vst1_u8(out, p1); out += out_stride;
|
|
vst1_u8(out, p2); out += out_stride;
|
|
vst1_u8(out, p3); out += out_stride;
|
|
vst1_u8(out, p4); out += out_stride;
|
|
vst1_u8(out, p5); out += out_stride;
|
|
vst1_u8(out, p6); out += out_stride;
|
|
vst1_u8(out, p7);
|
|
|
|
#undef dct_trn8_8
|
|
#undef dct_trn8_16
|
|
#undef dct_trn8_32
|
|
}
|
|
|
|
#undef dct_long_mul
|
|
#undef dct_long_mac
|
|
#undef dct_widen
|
|
#undef dct_wadd
|
|
#undef dct_wsub
|
|
#undef dct_bfly32o
|
|
#undef dct_pass
|
|
}
|
|
|
|
#endif // STBI_NEON
|
|
|
|
#define STBI__MARKER_none 0xff
|
|
// if there's a pending marker from the entropy stream, return that
|
|
// otherwise, fetch from the stream and get a marker. if there's no
|
|
// marker, return 0xff, which is never a valid marker value
|
|
static stbi_uc stbi__get_marker(stbi__jpeg *j)
|
|
{
|
|
stbi_uc x;
|
|
if (j->marker != STBI__MARKER_none) { x = j->marker; j->marker = STBI__MARKER_none; return x; }
|
|
x = stbi__get8(j->s);
|
|
if (x != 0xff) return STBI__MARKER_none;
|
|
while (x == 0xff)
|
|
x = stbi__get8(j->s);
|
|
return x;
|
|
}
|
|
|
|
// in each scan, we'll have scan_n components, and the order
|
|
// of the components is specified by order[]
|
|
#define STBI__RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7)
|
|
|
|
// after a restart interval, stbi__jpeg_reset the entropy decoder and
|
|
// the dc prediction
|
|
static void stbi__jpeg_reset(stbi__jpeg *j)
|
|
{
|
|
j->code_bits = 0;
|
|
j->code_buffer = 0;
|
|
j->nomore = 0;
|
|
j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = 0;
|
|
j->marker = STBI__MARKER_none;
|
|
j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff;
|
|
j->eob_run = 0;
|
|
// no more than 1<<31 MCUs if no restart_interal? that's plenty safe,
|
|
// since we don't even allow 1<<30 pixels
|
|
}
|
|
|
|
static int stbi__parse_entropy_coded_data(stbi__jpeg *z)
|
|
{
|
|
stbi__jpeg_reset(z);
|
|
if (!z->progressive) {
|
|
if (z->scan_n == 1) {
|
|
int i,j;
|
|
STBI_SIMD_ALIGN(short, data[64]);
|
|
int n = z->order[0];
|
|
// non-interleaved data, we just need to process one block at a time,
|
|
// in trivial scanline order
|
|
// number of blocks to do just depends on how many actual "pixels" this
|
|
// component has, independent of interleaved MCU blocking and such
|
|
int w = (z->img_comp[n].x+7) >> 3;
|
|
int h = (z->img_comp[n].y+7) >> 3;
|
|
for (j=0; j < h; ++j) {
|
|
for (i=0; i < w; ++i) {
|
|
int ha = z->img_comp[n].ha;
|
|
if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0;
|
|
z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data);
|
|
// every data block is an MCU, so countdown the restart interval
|
|
if (--z->todo <= 0) {
|
|
if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
|
|
// if it's NOT a restart, then just bail, so we get corrupt data
|
|
// rather than no data
|
|
if (!STBI__RESTART(z->marker)) return 1;
|
|
stbi__jpeg_reset(z);
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
} else { // interleaved
|
|
int i,j,k,x,y;
|
|
STBI_SIMD_ALIGN(short, data[64]);
|
|
for (j=0; j < z->img_mcu_y; ++j) {
|
|
for (i=0; i < z->img_mcu_x; ++i) {
|
|
// scan an interleaved mcu... process scan_n components in order
|
|
for (k=0; k < z->scan_n; ++k) {
|
|
int n = z->order[k];
|
|
// scan out an mcu's worth of this component; that's just determined
|
|
// by the basic H and V specified for the component
|
|
for (y=0; y < z->img_comp[n].v; ++y) {
|
|
for (x=0; x < z->img_comp[n].h; ++x) {
|
|
int x2 = (i*z->img_comp[n].h + x)*8;
|
|
int y2 = (j*z->img_comp[n].v + y)*8;
|
|
int ha = z->img_comp[n].ha;
|
|
if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0;
|
|
z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data);
|
|
}
|
|
}
|
|
}
|
|
// after all interleaved components, that's an interleaved MCU,
|
|
// so now count down the restart interval
|
|
if (--z->todo <= 0) {
|
|
if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
|
|
if (!STBI__RESTART(z->marker)) return 1;
|
|
stbi__jpeg_reset(z);
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
} else {
|
|
if (z->scan_n == 1) {
|
|
int i,j;
|
|
int n = z->order[0];
|
|
// non-interleaved data, we just need to process one block at a time,
|
|
// in trivial scanline order
|
|
// number of blocks to do just depends on how many actual "pixels" this
|
|
// component has, independent of interleaved MCU blocking and such
|
|
int w = (z->img_comp[n].x+7) >> 3;
|
|
int h = (z->img_comp[n].y+7) >> 3;
|
|
for (j=0; j < h; ++j) {
|
|
for (i=0; i < w; ++i) {
|
|
short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w);
|
|
if (z->spec_start == 0) {
|
|
if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n))
|
|
return 0;
|
|
} else {
|
|
int ha = z->img_comp[n].ha;
|
|
if (!stbi__jpeg_decode_block_prog_ac(z, data, &z->huff_ac[ha], z->fast_ac[ha]))
|
|
return 0;
|
|
}
|
|
// every data block is an MCU, so countdown the restart interval
|
|
if (--z->todo <= 0) {
|
|
if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
|
|
if (!STBI__RESTART(z->marker)) return 1;
|
|
stbi__jpeg_reset(z);
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
} else { // interleaved
|
|
int i,j,k,x,y;
|
|
for (j=0; j < z->img_mcu_y; ++j) {
|
|
for (i=0; i < z->img_mcu_x; ++i) {
|
|
// scan an interleaved mcu... process scan_n components in order
|
|
for (k=0; k < z->scan_n; ++k) {
|
|
int n = z->order[k];
|
|
// scan out an mcu's worth of this component; that's just determined
|
|
// by the basic H and V specified for the component
|
|
for (y=0; y < z->img_comp[n].v; ++y) {
|
|
for (x=0; x < z->img_comp[n].h; ++x) {
|
|
int x2 = (i*z->img_comp[n].h + x);
|
|
int y2 = (j*z->img_comp[n].v + y);
|
|
short *data = z->img_comp[n].coeff + 64 * (x2 + y2 * z->img_comp[n].coeff_w);
|
|
if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n))
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
// after all interleaved components, that's an interleaved MCU,
|
|
// so now count down the restart interval
|
|
if (--z->todo <= 0) {
|
|
if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
|
|
if (!STBI__RESTART(z->marker)) return 1;
|
|
stbi__jpeg_reset(z);
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void stbi__jpeg_dequantize(short *data, stbi_uc *dequant)
|
|
{
|
|
int i;
|
|
for (i=0; i < 64; ++i)
|
|
data[i] *= dequant[i];
|
|
}
|
|
|
|
static void stbi__jpeg_finish(stbi__jpeg *z)
|
|
{
|
|
if (z->progressive) {
|
|
// dequantize and idct the data
|
|
int i,j,n;
|
|
for (n=0; n < z->s->img_n; ++n) {
|
|
int w = (z->img_comp[n].x+7) >> 3;
|
|
int h = (z->img_comp[n].y+7) >> 3;
|
|
for (j=0; j < h; ++j) {
|
|
for (i=0; i < w; ++i) {
|
|
short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w);
|
|
stbi__jpeg_dequantize(data, z->dequant[z->img_comp[n].tq]);
|
|
z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int stbi__process_marker(stbi__jpeg *z, int m)
|
|
{
|
|
int L;
|
|
switch (m) {
|
|
case STBI__MARKER_none: // no marker found
|
|
return stbi__err("expected marker","Corrupt JPEG");
|
|
|
|
case 0xDD: // DRI - specify restart interval
|
|
if (stbi__get16be(z->s) != 4) return stbi__err("bad DRI len","Corrupt JPEG");
|
|
z->restart_interval = stbi__get16be(z->s);
|
|
return 1;
|
|
|
|
case 0xDB: // DQT - define quantization table
|
|
L = stbi__get16be(z->s)-2;
|
|
while (L > 0) {
|
|
int q = stbi__get8(z->s);
|
|
int p = q >> 4;
|
|
int t = q & 15,i;
|
|
if (p != 0) return stbi__err("bad DQT type","Corrupt JPEG");
|
|
if (t > 3) return stbi__err("bad DQT table","Corrupt JPEG");
|
|
for (i=0; i < 64; ++i)
|
|
z->dequant[t][stbi__jpeg_dezigzag[i]] = stbi__get8(z->s);
|
|
L -= 65;
|
|
}
|
|
return L==0;
|
|
|
|
case 0xC4: // DHT - define huffman table
|
|
L = stbi__get16be(z->s)-2;
|
|
while (L > 0) {
|
|
stbi_uc *v;
|
|
int sizes[16],i,n=0;
|
|
int q = stbi__get8(z->s);
|
|
int tc = q >> 4;
|
|
int th = q & 15;
|
|
if (tc > 1 || th > 3) return stbi__err("bad DHT header","Corrupt JPEG");
|
|
for (i=0; i < 16; ++i) {
|
|
sizes[i] = stbi__get8(z->s);
|
|
n += sizes[i];
|
|
}
|
|
L -= 17;
|
|
if (tc == 0) {
|
|
if (!stbi__build_huffman(z->huff_dc+th, sizes)) return 0;
|
|
v = z->huff_dc[th].values;
|
|
} else {
|
|
if (!stbi__build_huffman(z->huff_ac+th, sizes)) return 0;
|
|
v = z->huff_ac[th].values;
|
|
}
|
|
for (i=0; i < n; ++i)
|
|
v[i] = stbi__get8(z->s);
|
|
if (tc != 0)
|
|
stbi__build_fast_ac(z->fast_ac[th], z->huff_ac + th);
|
|
L -= n;
|
|
}
|
|
return L==0;
|
|
}
|
|
// check for comment block or APP blocks
|
|
if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) {
|
|
stbi__skip(z->s, stbi__get16be(z->s)-2);
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
// after we see SOS
|
|
static int stbi__process_scan_header(stbi__jpeg *z)
|
|
{
|
|
int i;
|
|
int Ls = stbi__get16be(z->s);
|
|
z->scan_n = stbi__get8(z->s);
|
|
if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int) z->s->img_n) return stbi__err("bad SOS component count","Corrupt JPEG");
|
|
if (Ls != 6+2*z->scan_n) return stbi__err("bad SOS len","Corrupt JPEG");
|
|
for (i=0; i < z->scan_n; ++i) {
|
|
int id = stbi__get8(z->s), which;
|
|
int q = stbi__get8(z->s);
|
|
for (which = 0; which < z->s->img_n; ++which)
|
|
if (z->img_comp[which].id == id)
|
|
break;
|
|
if (which == z->s->img_n) return 0; // no match
|
|
z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return stbi__err("bad DC huff","Corrupt JPEG");
|
|
z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return stbi__err("bad AC huff","Corrupt JPEG");
|
|
z->order[i] = which;
|
|
}
|
|
|
|
{
|
|
int aa;
|
|
z->spec_start = stbi__get8(z->s);
|
|
z->spec_end = stbi__get8(z->s); // should be 63, but might be 0
|
|
aa = stbi__get8(z->s);
|
|
z->succ_high = (aa >> 4);
|
|
z->succ_low = (aa & 15);
|
|
if (z->progressive) {
|
|
if (z->spec_start > 63 || z->spec_end > 63 || z->spec_start > z->spec_end || z->succ_high > 13 || z->succ_low > 13)
|
|
return stbi__err("bad SOS", "Corrupt JPEG");
|
|
} else {
|
|
if (z->spec_start != 0) return stbi__err("bad SOS","Corrupt JPEG");
|
|
if (z->succ_high != 0 || z->succ_low != 0) return stbi__err("bad SOS","Corrupt JPEG");
|
|
z->spec_end = 63;
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__process_frame_header(stbi__jpeg *z, int scan)
|
|
{
|
|
stbi__context *s = z->s;
|
|
int Lf,p,i,q, h_max=1,v_max=1,c;
|
|
Lf = stbi__get16be(s); if (Lf < 11) return stbi__err("bad SOF len","Corrupt JPEG"); // JPEG
|
|
p = stbi__get8(s); if (p != 8) return stbi__err("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline
|
|
s->img_y = stbi__get16be(s); if (s->img_y == 0) return stbi__err("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG
|
|
s->img_x = stbi__get16be(s); if (s->img_x == 0) return stbi__err("0 width","Corrupt JPEG"); // JPEG requires
|
|
c = stbi__get8(s);
|
|
if (c != 3 && c != 1) return stbi__err("bad component count","Corrupt JPEG"); // JFIF requires
|
|
s->img_n = c;
|
|
for (i=0; i < c; ++i) {
|
|
z->img_comp[i].data = NULL;
|
|
z->img_comp[i].linebuf = NULL;
|
|
}
|
|
|
|
if (Lf != 8+3*s->img_n) return stbi__err("bad SOF len","Corrupt JPEG");
|
|
|
|
z->rgb = 0;
|
|
for (i=0; i < s->img_n; ++i) {
|
|
static unsigned char rgb[3] = { 'R', 'G', 'B' };
|
|
z->img_comp[i].id = stbi__get8(s);
|
|
if (z->img_comp[i].id != i+1) // JFIF requires
|
|
if (z->img_comp[i].id != i) { // some version of jpegtran outputs non-JFIF-compliant files!
|
|
// somethings output this (see http://fileformats.archiveteam.org/wiki/JPEG#Color_format)
|
|
if (z->img_comp[i].id != rgb[i])
|
|
return stbi__err("bad component ID","Corrupt JPEG");
|
|
++z->rgb;
|
|
}
|
|
q = stbi__get8(s);
|
|
z->img_comp[i].h = (q >> 4); if (!z->img_comp[i].h || z->img_comp[i].h > 4) return stbi__err("bad H","Corrupt JPEG");
|
|
z->img_comp[i].v = q & 15; if (!z->img_comp[i].v || z->img_comp[i].v > 4) return stbi__err("bad V","Corrupt JPEG");
|
|
z->img_comp[i].tq = stbi__get8(s); if (z->img_comp[i].tq > 3) return stbi__err("bad TQ","Corrupt JPEG");
|
|
}
|
|
|
|
if (scan != STBI__SCAN_load) return 1;
|
|
|
|
if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode");
|
|
|
|
for (i=0; i < s->img_n; ++i) {
|
|
if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h;
|
|
if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v;
|
|
}
|
|
|
|
// compute interleaved mcu info
|
|
z->img_h_max = h_max;
|
|
z->img_v_max = v_max;
|
|
z->img_mcu_w = h_max * 8;
|
|
z->img_mcu_h = v_max * 8;
|
|
z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w;
|
|
z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h;
|
|
|
|
for (i=0; i < s->img_n; ++i) {
|
|
// number of effective pixels (e.g. for non-interleaved MCU)
|
|
z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max;
|
|
z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max;
|
|
// to simplify generation, we'll allocate enough memory to decode
|
|
// the bogus oversized data from using interleaved MCUs and their
|
|
// big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't
|
|
// discard the extra data until colorspace conversion
|
|
z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8;
|
|
z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8;
|
|
z->img_comp[i].raw_data = stbi__malloc(z->img_comp[i].w2 * z->img_comp[i].h2+15);
|
|
|
|
if (z->img_comp[i].raw_data == NULL) {
|
|
for(--i; i >= 0; --i) {
|
|
STBI_FREE(z->img_comp[i].raw_data);
|
|
z->img_comp[i].raw_data = NULL;
|
|
}
|
|
return stbi__err("outofmem", "Out of memory");
|
|
}
|
|
// align blocks for idct using mmx/sse
|
|
z->img_comp[i].data = (stbi_uc*) (((size_t) z->img_comp[i].raw_data + 15) & ~15);
|
|
z->img_comp[i].linebuf = NULL;
|
|
if (z->progressive) {
|
|
z->img_comp[i].coeff_w = (z->img_comp[i].w2 + 7) >> 3;
|
|
z->img_comp[i].coeff_h = (z->img_comp[i].h2 + 7) >> 3;
|
|
z->img_comp[i].raw_coeff = STBI_MALLOC(z->img_comp[i].coeff_w * z->img_comp[i].coeff_h * 64 * sizeof(short) + 15);
|
|
z->img_comp[i].coeff = (short*) (((size_t) z->img_comp[i].raw_coeff + 15) & ~15);
|
|
} else {
|
|
z->img_comp[i].coeff = 0;
|
|
z->img_comp[i].raw_coeff = 0;
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
// use comparisons since in some cases we handle more than one case (e.g. SOF)
|
|
#define stbi__DNL(x) ((x) == 0xdc)
|
|
#define stbi__SOI(x) ((x) == 0xd8)
|
|
#define stbi__EOI(x) ((x) == 0xd9)
|
|
#define stbi__SOF(x) ((x) == 0xc0 || (x) == 0xc1 || (x) == 0xc2)
|
|
#define stbi__SOS(x) ((x) == 0xda)
|
|
|
|
#define stbi__SOF_progressive(x) ((x) == 0xc2)
|
|
|
|
static int stbi__decode_jpeg_header(stbi__jpeg *z, int scan)
|
|
{
|
|
int m;
|
|
z->marker = STBI__MARKER_none; // initialize cached marker to empty
|
|
m = stbi__get_marker(z);
|
|
if (!stbi__SOI(m)) return stbi__err("no SOI","Corrupt JPEG");
|
|
if (scan == STBI__SCAN_type) return 1;
|
|
m = stbi__get_marker(z);
|
|
while (!stbi__SOF(m)) {
|
|
if (!stbi__process_marker(z,m)) return 0;
|
|
m = stbi__get_marker(z);
|
|
while (m == STBI__MARKER_none) {
|
|
// some files have extra padding after their blocks, so ok, we'll scan
|
|
if (stbi__at_eof(z->s)) return stbi__err("no SOF", "Corrupt JPEG");
|
|
m = stbi__get_marker(z);
|
|
}
|
|
}
|
|
z->progressive = stbi__SOF_progressive(m);
|
|
if (!stbi__process_frame_header(z, scan)) return 0;
|
|
return 1;
|
|
}
|
|
|
|
// decode image to YCbCr format
|
|
static int stbi__decode_jpeg_image(stbi__jpeg *j)
|
|
{
|
|
int m;
|
|
for (m = 0; m < 4; m++) {
|
|
j->img_comp[m].raw_data = NULL;
|
|
j->img_comp[m].raw_coeff = NULL;
|
|
}
|
|
j->restart_interval = 0;
|
|
if (!stbi__decode_jpeg_header(j, STBI__SCAN_load)) return 0;
|
|
m = stbi__get_marker(j);
|
|
while (!stbi__EOI(m)) {
|
|
if (stbi__SOS(m)) {
|
|
if (!stbi__process_scan_header(j)) return 0;
|
|
if (!stbi__parse_entropy_coded_data(j)) return 0;
|
|
if (j->marker == STBI__MARKER_none ) {
|
|
// handle 0s at the end of image data from IP Kamera 9060
|
|
while (!stbi__at_eof(j->s)) {
|
|
int x = stbi__get8(j->s);
|
|
if (x == 255) {
|
|
j->marker = stbi__get8(j->s);
|
|
break;
|
|
} else if (x != 0) {
|
|
return stbi__err("junk before marker", "Corrupt JPEG");
|
|
}
|
|
}
|
|
// if we reach eof without hitting a marker, stbi__get_marker() below will fail and we'll eventually return 0
|
|
}
|
|
} else {
|
|
if (!stbi__process_marker(j, m)) return 0;
|
|
}
|
|
m = stbi__get_marker(j);
|
|
}
|
|
if (j->progressive)
|
|
stbi__jpeg_finish(j);
|
|
return 1;
|
|
}
|
|
|
|
// static jfif-centered resampling (across block boundaries)
|
|
|
|
typedef stbi_uc *(*resample_row_func)(stbi_uc *out, stbi_uc *in0, stbi_uc *in1,
|
|
int w, int hs);
|
|
|
|
#define stbi__div4(x) ((stbi_uc) ((x) >> 2))
|
|
|
|
static stbi_uc *resample_row_1(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
|
|
{
|
|
STBI_NOTUSED(out);
|
|
STBI_NOTUSED(in_far);
|
|
STBI_NOTUSED(w);
|
|
STBI_NOTUSED(hs);
|
|
return in_near;
|
|
}
|
|
|
|
static stbi_uc* stbi__resample_row_v_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
|
|
{
|
|
// need to generate two samples vertically for every one in input
|
|
int i;
|
|
STBI_NOTUSED(hs);
|
|
for (i=0; i < w; ++i)
|
|
out[i] = stbi__div4(3*in_near[i] + in_far[i] + 2);
|
|
return out;
|
|
}
|
|
|
|
static stbi_uc* stbi__resample_row_h_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
|
|
{
|
|
// need to generate two samples horizontally for every one in input
|
|
int i;
|
|
stbi_uc *input = in_near;
|
|
|
|
if (w == 1) {
|
|
// if only one sample, can't do any interpolation
|
|
out[0] = out[1] = input[0];
|
|
return out;
|
|
}
|
|
|
|
out[0] = input[0];
|
|
out[1] = stbi__div4(input[0]*3 + input[1] + 2);
|
|
for (i=1; i < w-1; ++i) {
|
|
int n = 3*input[i]+2;
|
|
out[i*2+0] = stbi__div4(n+input[i-1]);
|
|
out[i*2+1] = stbi__div4(n+input[i+1]);
|
|
}
|
|
out[i*2+0] = stbi__div4(input[w-2]*3 + input[w-1] + 2);
|
|
out[i*2+1] = input[w-1];
|
|
|
|
STBI_NOTUSED(in_far);
|
|
STBI_NOTUSED(hs);
|
|
|
|
return out;
|
|
}
|
|
|
|
#define stbi__div16(x) ((stbi_uc) ((x) >> 4))
|
|
|
|
static stbi_uc *stbi__resample_row_hv_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
|
|
{
|
|
// need to generate 2x2 samples for every one in input
|
|
int i,t0,t1;
|
|
if (w == 1) {
|
|
out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2);
|
|
return out;
|
|
}
|
|
|
|
t1 = 3*in_near[0] + in_far[0];
|
|
out[0] = stbi__div4(t1+2);
|
|
for (i=1; i < w; ++i) {
|
|
t0 = t1;
|
|
t1 = 3*in_near[i]+in_far[i];
|
|
out[i*2-1] = stbi__div16(3*t0 + t1 + 8);
|
|
out[i*2 ] = stbi__div16(3*t1 + t0 + 8);
|
|
}
|
|
out[w*2-1] = stbi__div4(t1+2);
|
|
|
|
STBI_NOTUSED(hs);
|
|
|
|
return out;
|
|
}
|
|
|
|
#if defined(STBI_SSE2) || defined(STBI_NEON)
|
|
static stbi_uc *stbi__resample_row_hv_2_simd(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
|
|
{
|
|
// need to generate 2x2 samples for every one in input
|
|
int i=0,t0,t1;
|
|
|
|
if (w == 1) {
|
|
out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2);
|
|
return out;
|
|
}
|
|
|
|
t1 = 3*in_near[0] + in_far[0];
|
|
// process groups of 8 pixels for as long as we can.
|
|
// note we can't handle the last pixel in a row in this loop
|
|
// because we need to handle the filter boundary conditions.
|
|
for (; i < ((w-1) & ~7); i += 8) {
|
|
#if defined(STBI_SSE2)
|
|
// load and perform the vertical filtering pass
|
|
// this uses 3*x + y = 4*x + (y - x)
|
|
__m128i zero = _mm_setzero_si128();
|
|
__m128i farb = _mm_loadl_epi64((__m128i *) (in_far + i));
|
|
__m128i nearb = _mm_loadl_epi64((__m128i *) (in_near + i));
|
|
__m128i farw = _mm_unpacklo_epi8(farb, zero);
|
|
__m128i nearw = _mm_unpacklo_epi8(nearb, zero);
|
|
__m128i diff = _mm_sub_epi16(farw, nearw);
|
|
__m128i nears = _mm_slli_epi16(nearw, 2);
|
|
__m128i curr = _mm_add_epi16(nears, diff); // current row
|
|
|
|
// horizontal filter works the same based on shifted vers of current
|
|
// row. "prev" is current row shifted right by 1 pixel; we need to
|
|
// insert the previous pixel value (from t1).
|
|
// "next" is current row shifted left by 1 pixel, with first pixel
|
|
// of next block of 8 pixels added in.
|
|
__m128i prv0 = _mm_slli_si128(curr, 2);
|
|
__m128i nxt0 = _mm_srli_si128(curr, 2);
|
|
__m128i prev = _mm_insert_epi16(prv0, t1, 0);
|
|
__m128i next = _mm_insert_epi16(nxt0, 3*in_near[i+8] + in_far[i+8], 7);
|
|
|
|
// horizontal filter, polyphase implementation since it's convenient:
|
|
// even pixels = 3*cur + prev = cur*4 + (prev - cur)
|
|
// odd pixels = 3*cur + next = cur*4 + (next - cur)
|
|
// note the shared term.
|
|
__m128i bias = _mm_set1_epi16(8);
|
|
__m128i curs = _mm_slli_epi16(curr, 2);
|
|
__m128i prvd = _mm_sub_epi16(prev, curr);
|
|
__m128i nxtd = _mm_sub_epi16(next, curr);
|
|
__m128i curb = _mm_add_epi16(curs, bias);
|
|
__m128i even = _mm_add_epi16(prvd, curb);
|
|
__m128i odd = _mm_add_epi16(nxtd, curb);
|
|
|
|
// interleave even and odd pixels, then undo scaling.
|
|
__m128i int0 = _mm_unpacklo_epi16(even, odd);
|
|
__m128i int1 = _mm_unpackhi_epi16(even, odd);
|
|
__m128i de0 = _mm_srli_epi16(int0, 4);
|
|
__m128i de1 = _mm_srli_epi16(int1, 4);
|
|
|
|
// pack and write output
|
|
__m128i outv = _mm_packus_epi16(de0, de1);
|
|
_mm_storeu_si128((__m128i *) (out + i*2), outv);
|
|
#elif defined(STBI_NEON)
|
|
// load and perform the vertical filtering pass
|
|
// this uses 3*x + y = 4*x + (y - x)
|
|
uint8x8_t farb = vld1_u8(in_far + i);
|
|
uint8x8_t nearb = vld1_u8(in_near + i);
|
|
int16x8_t diff = vreinterpretq_s16_u16(vsubl_u8(farb, nearb));
|
|
int16x8_t nears = vreinterpretq_s16_u16(vshll_n_u8(nearb, 2));
|
|
int16x8_t curr = vaddq_s16(nears, diff); // current row
|
|
|
|
// horizontal filter works the same based on shifted vers of current
|
|
// row. "prev" is current row shifted right by 1 pixel; we need to
|
|
// insert the previous pixel value (from t1).
|
|
// "next" is current row shifted left by 1 pixel, with first pixel
|
|
// of next block of 8 pixels added in.
|
|
int16x8_t prv0 = vextq_s16(curr, curr, 7);
|
|
int16x8_t nxt0 = vextq_s16(curr, curr, 1);
|
|
int16x8_t prev = vsetq_lane_s16(t1, prv0, 0);
|
|
int16x8_t next = vsetq_lane_s16(3*in_near[i+8] + in_far[i+8], nxt0, 7);
|
|
|
|
// horizontal filter, polyphase implementation since it's convenient:
|
|
// even pixels = 3*cur + prev = cur*4 + (prev - cur)
|
|
// odd pixels = 3*cur + next = cur*4 + (next - cur)
|
|
// note the shared term.
|
|
int16x8_t curs = vshlq_n_s16(curr, 2);
|
|
int16x8_t prvd = vsubq_s16(prev, curr);
|
|
int16x8_t nxtd = vsubq_s16(next, curr);
|
|
int16x8_t even = vaddq_s16(curs, prvd);
|
|
int16x8_t odd = vaddq_s16(curs, nxtd);
|
|
|
|
// undo scaling and round, then store with even/odd phases interleaved
|
|
uint8x8x2_t o;
|
|
o.val[0] = vqrshrun_n_s16(even, 4);
|
|
o.val[1] = vqrshrun_n_s16(odd, 4);
|
|
vst2_u8(out + i*2, o);
|
|
#endif
|
|
|
|
// "previous" value for next iter
|
|
t1 = 3*in_near[i+7] + in_far[i+7];
|
|
}
|
|
|
|
t0 = t1;
|
|
t1 = 3*in_near[i] + in_far[i];
|
|
out[i*2] = stbi__div16(3*t1 + t0 + 8);
|
|
|
|
for (++i; i < w; ++i) {
|
|
t0 = t1;
|
|
t1 = 3*in_near[i]+in_far[i];
|
|
out[i*2-1] = stbi__div16(3*t0 + t1 + 8);
|
|
out[i*2 ] = stbi__div16(3*t1 + t0 + 8);
|
|
}
|
|
out[w*2-1] = stbi__div4(t1+2);
|
|
|
|
STBI_NOTUSED(hs);
|
|
|
|
return out;
|
|
}
|
|
#endif
|
|
|
|
static stbi_uc *stbi__resample_row_generic(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
|
|
{
|
|
// resample with nearest-neighbor
|
|
int i,j;
|
|
STBI_NOTUSED(in_far);
|
|
for (i=0; i < w; ++i)
|
|
for (j=0; j < hs; ++j)
|
|
out[i*hs+j] = in_near[i];
|
|
return out;
|
|
}
|
|
|
|
#ifdef STBI_JPEG_OLD
|
|
// this is the same YCbCr-to-RGB calculation that stb_image has used
|
|
// historically before the algorithm changes in 1.49
|
|
#define float2fixed(x) ((int) ((x) * 65536 + 0.5))
|
|
static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step)
|
|
{
|
|
int i;
|
|
for (i=0; i < count; ++i) {
|
|
int y_fixed = (y[i] << 16) + 32768; // rounding
|
|
int r,g,b;
|
|
int cr = pcr[i] - 128;
|
|
int cb = pcb[i] - 128;
|
|
r = y_fixed + cr*float2fixed(1.40200f);
|
|
g = y_fixed - cr*float2fixed(0.71414f) - cb*float2fixed(0.34414f);
|
|
b = y_fixed + cb*float2fixed(1.77200f);
|
|
r >>= 16;
|
|
g >>= 16;
|
|
b >>= 16;
|
|
if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
|
|
if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
|
|
if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
|
|
out[0] = (stbi_uc)r;
|
|
out[1] = (stbi_uc)g;
|
|
out[2] = (stbi_uc)b;
|
|
out[3] = 255;
|
|
out += step;
|
|
}
|
|
}
|
|
#else
|
|
// this is a reduced-precision calculation of YCbCr-to-RGB introduced
|
|
// to make sure the code produces the same results in both SIMD and scalar
|
|
#define float2fixed(x) (((int) ((x) * 4096.0f + 0.5f)) << 8)
|
|
static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step)
|
|
{
|
|
int i;
|
|
for (i=0; i < count; ++i) {
|
|
int y_fixed = (y[i] << 20) + (1<<19); // rounding
|
|
int r,g,b;
|
|
int cr = pcr[i] - 128;
|
|
int cb = pcb[i] - 128;
|
|
r = y_fixed + cr* float2fixed(1.40200f);
|
|
g = y_fixed + (cr*-float2fixed(0.71414f)) + ((cb*-float2fixed(0.34414f)) & 0xffff0000);
|
|
b = y_fixed + cb* float2fixed(1.77200f);
|
|
r >>= 20;
|
|
g >>= 20;
|
|
b >>= 20;
|
|
if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
|
|
if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
|
|
if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
|
|
out[0] = (stbi_uc)r;
|
|
out[1] = (stbi_uc)g;
|
|
out[2] = (stbi_uc)b;
|
|
out[3] = 255;
|
|
out += step;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if defined(STBI_SSE2) || defined(STBI_NEON)
|
|
static void stbi__YCbCr_to_RGB_simd(stbi_uc *out, stbi_uc const *y, stbi_uc const *pcb, stbi_uc const *pcr, int count, int step)
|
|
{
|
|
int i = 0;
|
|
|
|
#ifdef STBI_SSE2
|
|
// step == 3 is pretty ugly on the final interleave, and i'm not convinced
|
|
// it's useful in practice (you wouldn't use it for textures, for example).
|
|
// so just accelerate step == 4 case.
|
|
if (step == 4) {
|
|
// this is a fairly straightforward implementation and not super-optimized.
|
|
__m128i signflip = _mm_set1_epi8(-0x80);
|
|
__m128i cr_const0 = _mm_set1_epi16( (short) ( 1.40200f*4096.0f+0.5f));
|
|
__m128i cr_const1 = _mm_set1_epi16( - (short) ( 0.71414f*4096.0f+0.5f));
|
|
__m128i cb_const0 = _mm_set1_epi16( - (short) ( 0.34414f*4096.0f+0.5f));
|
|
__m128i cb_const1 = _mm_set1_epi16( (short) ( 1.77200f*4096.0f+0.5f));
|
|
__m128i y_bias = _mm_set1_epi8((char) (unsigned char) 128);
|
|
__m128i xw = _mm_set1_epi16(255); // alpha channel
|
|
|
|
for (; i+7 < count; i += 8) {
|
|
// load
|
|
__m128i y_bytes = _mm_loadl_epi64((__m128i *) (y+i));
|
|
__m128i cr_bytes = _mm_loadl_epi64((__m128i *) (pcr+i));
|
|
__m128i cb_bytes = _mm_loadl_epi64((__m128i *) (pcb+i));
|
|
__m128i cr_biased = _mm_xor_si128(cr_bytes, signflip); // -128
|
|
__m128i cb_biased = _mm_xor_si128(cb_bytes, signflip); // -128
|
|
|
|
// unpack to short (and left-shift cr, cb by 8)
|
|
__m128i yw = _mm_unpacklo_epi8(y_bias, y_bytes);
|
|
__m128i crw = _mm_unpacklo_epi8(_mm_setzero_si128(), cr_biased);
|
|
__m128i cbw = _mm_unpacklo_epi8(_mm_setzero_si128(), cb_biased);
|
|
|
|
// color transform
|
|
__m128i yws = _mm_srli_epi16(yw, 4);
|
|
__m128i cr0 = _mm_mulhi_epi16(cr_const0, crw);
|
|
__m128i cb0 = _mm_mulhi_epi16(cb_const0, cbw);
|
|
__m128i cb1 = _mm_mulhi_epi16(cbw, cb_const1);
|
|
__m128i cr1 = _mm_mulhi_epi16(crw, cr_const1);
|
|
__m128i rws = _mm_add_epi16(cr0, yws);
|
|
__m128i gwt = _mm_add_epi16(cb0, yws);
|
|
__m128i bws = _mm_add_epi16(yws, cb1);
|
|
__m128i gws = _mm_add_epi16(gwt, cr1);
|
|
|
|
// descale
|
|
__m128i rw = _mm_srai_epi16(rws, 4);
|
|
__m128i bw = _mm_srai_epi16(bws, 4);
|
|
__m128i gw = _mm_srai_epi16(gws, 4);
|
|
|
|
// back to byte, set up for transpose
|
|
__m128i brb = _mm_packus_epi16(rw, bw);
|
|
__m128i gxb = _mm_packus_epi16(gw, xw);
|
|
|
|
// transpose to interleave channels
|
|
__m128i t0 = _mm_unpacklo_epi8(brb, gxb);
|
|
__m128i t1 = _mm_unpackhi_epi8(brb, gxb);
|
|
__m128i o0 = _mm_unpacklo_epi16(t0, t1);
|
|
__m128i o1 = _mm_unpackhi_epi16(t0, t1);
|
|
|
|
// store
|
|
_mm_storeu_si128((__m128i *) (out + 0), o0);
|
|
_mm_storeu_si128((__m128i *) (out + 16), o1);
|
|
out += 32;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef STBI_NEON
|
|
// in this version, step=3 support would be easy to add. but is there demand?
|
|
if (step == 4) {
|
|
// this is a fairly straightforward implementation and not super-optimized.
|
|
uint8x8_t signflip = vdup_n_u8(0x80);
|
|
int16x8_t cr_const0 = vdupq_n_s16( (short) ( 1.40200f*4096.0f+0.5f));
|
|
int16x8_t cr_const1 = vdupq_n_s16( - (short) ( 0.71414f*4096.0f+0.5f));
|
|
int16x8_t cb_const0 = vdupq_n_s16( - (short) ( 0.34414f*4096.0f+0.5f));
|
|
int16x8_t cb_const1 = vdupq_n_s16( (short) ( 1.77200f*4096.0f+0.5f));
|
|
|
|
for (; i+7 < count; i += 8) {
|
|
// load
|
|
uint8x8_t y_bytes = vld1_u8(y + i);
|
|
uint8x8_t cr_bytes = vld1_u8(pcr + i);
|
|
uint8x8_t cb_bytes = vld1_u8(pcb + i);
|
|
int8x8_t cr_biased = vreinterpret_s8_u8(vsub_u8(cr_bytes, signflip));
|
|
int8x8_t cb_biased = vreinterpret_s8_u8(vsub_u8(cb_bytes, signflip));
|
|
|
|
// expand to s16
|
|
int16x8_t yws = vreinterpretq_s16_u16(vshll_n_u8(y_bytes, 4));
|
|
int16x8_t crw = vshll_n_s8(cr_biased, 7);
|
|
int16x8_t cbw = vshll_n_s8(cb_biased, 7);
|
|
|
|
// color transform
|
|
int16x8_t cr0 = vqdmulhq_s16(crw, cr_const0);
|
|
int16x8_t cb0 = vqdmulhq_s16(cbw, cb_const0);
|
|
int16x8_t cr1 = vqdmulhq_s16(crw, cr_const1);
|
|
int16x8_t cb1 = vqdmulhq_s16(cbw, cb_const1);
|
|
int16x8_t rws = vaddq_s16(yws, cr0);
|
|
int16x8_t gws = vaddq_s16(vaddq_s16(yws, cb0), cr1);
|
|
int16x8_t bws = vaddq_s16(yws, cb1);
|
|
|
|
// undo scaling, round, convert to byte
|
|
uint8x8x4_t o;
|
|
o.val[0] = vqrshrun_n_s16(rws, 4);
|
|
o.val[1] = vqrshrun_n_s16(gws, 4);
|
|
o.val[2] = vqrshrun_n_s16(bws, 4);
|
|
o.val[3] = vdup_n_u8(255);
|
|
|
|
// store, interleaving r/g/b/a
|
|
vst4_u8(out, o);
|
|
out += 8*4;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
for (; i < count; ++i) {
|
|
int y_fixed = (y[i] << 20) + (1<<19); // rounding
|
|
int r,g,b;
|
|
int cr = pcr[i] - 128;
|
|
int cb = pcb[i] - 128;
|
|
r = y_fixed + cr* float2fixed(1.40200f);
|
|
g = y_fixed + cr*-float2fixed(0.71414f) + ((cb*-float2fixed(0.34414f)) & 0xffff0000);
|
|
b = y_fixed + cb* float2fixed(1.77200f);
|
|
r >>= 20;
|
|
g >>= 20;
|
|
b >>= 20;
|
|
if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
|
|
if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
|
|
if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
|
|
out[0] = (stbi_uc)r;
|
|
out[1] = (stbi_uc)g;
|
|
out[2] = (stbi_uc)b;
|
|
out[3] = 255;
|
|
out += step;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
// set up the kernels
|
|
static void stbi__setup_jpeg(stbi__jpeg *j)
|
|
{
|
|
j->idct_block_kernel = stbi__idct_block;
|
|
j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_row;
|
|
j->resample_row_hv_2_kernel = stbi__resample_row_hv_2;
|
|
|
|
#ifdef STBI_SSE2
|
|
if (stbi__sse2_available()) {
|
|
j->idct_block_kernel = stbi__idct_simd;
|
|
#ifndef STBI_JPEG_OLD
|
|
j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd;
|
|
#endif
|
|
j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd;
|
|
}
|
|
#endif
|
|
|
|
#ifdef STBI_NEON
|
|
j->idct_block_kernel = stbi__idct_simd;
|
|
#ifndef STBI_JPEG_OLD
|
|
j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd;
|
|
#endif
|
|
j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd;
|
|
#endif
|
|
}
|
|
|
|
// clean up the temporary component buffers
|
|
static void stbi__cleanup_jpeg(stbi__jpeg *j)
|
|
{
|
|
int i;
|
|
for (i=0; i < j->s->img_n; ++i) {
|
|
if (j->img_comp[i].raw_data) {
|
|
STBI_FREE(j->img_comp[i].raw_data);
|
|
j->img_comp[i].raw_data = NULL;
|
|
j->img_comp[i].data = NULL;
|
|
}
|
|
if (j->img_comp[i].raw_coeff) {
|
|
STBI_FREE(j->img_comp[i].raw_coeff);
|
|
j->img_comp[i].raw_coeff = 0;
|
|
j->img_comp[i].coeff = 0;
|
|
}
|
|
if (j->img_comp[i].linebuf) {
|
|
STBI_FREE(j->img_comp[i].linebuf);
|
|
j->img_comp[i].linebuf = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
resample_row_func resample;
|
|
stbi_uc *line0,*line1;
|
|
int hs,vs; // expansion factor in each axis
|
|
int w_lores; // horizontal pixels pre-expansion
|
|
int ystep; // how far through vertical expansion we are
|
|
int ypos; // which pre-expansion row we're on
|
|
} stbi__resample;
|
|
|
|
static stbi_uc *load_jpeg_image(stbi__jpeg *z, int *out_x, int *out_y, int *comp, int req_comp)
|
|
{
|
|
int n, decode_n;
|
|
z->s->img_n = 0; // make stbi__cleanup_jpeg safe
|
|
|
|
// validate req_comp
|
|
if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
|
|
|
|
// load a jpeg image from whichever source, but leave in YCbCr format
|
|
if (!stbi__decode_jpeg_image(z)) { stbi__cleanup_jpeg(z); return NULL; }
|
|
|
|
// determine actual number of components to generate
|
|
n = req_comp ? req_comp : z->s->img_n;
|
|
|
|
if (z->s->img_n == 3 && n < 3)
|
|
decode_n = 1;
|
|
else
|
|
decode_n = z->s->img_n;
|
|
|
|
// resample and color-convert
|
|
{
|
|
int k;
|
|
unsigned int i,j;
|
|
stbi_uc *output;
|
|
stbi_uc *coutput[4];
|
|
|
|
stbi__resample res_comp[4];
|
|
|
|
for (k=0; k < decode_n; ++k) {
|
|
stbi__resample *r = &res_comp[k];
|
|
|
|
// allocate line buffer big enough for upsampling off the edges
|
|
// with upsample factor of 4
|
|
z->img_comp[k].linebuf = (stbi_uc *) stbi__malloc(z->s->img_x + 3);
|
|
if (!z->img_comp[k].linebuf) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); }
|
|
|
|
r->hs = z->img_h_max / z->img_comp[k].h;
|
|
r->vs = z->img_v_max / z->img_comp[k].v;
|
|
r->ystep = r->vs >> 1;
|
|
r->w_lores = (z->s->img_x + r->hs-1) / r->hs;
|
|
r->ypos = 0;
|
|
r->line0 = r->line1 = z->img_comp[k].data;
|
|
|
|
if (r->hs == 1 && r->vs == 1) r->resample = resample_row_1;
|
|
else if (r->hs == 1 && r->vs == 2) r->resample = stbi__resample_row_v_2;
|
|
else if (r->hs == 2 && r->vs == 1) r->resample = stbi__resample_row_h_2;
|
|
else if (r->hs == 2 && r->vs == 2) r->resample = z->resample_row_hv_2_kernel;
|
|
else r->resample = stbi__resample_row_generic;
|
|
}
|
|
|
|
// can't error after this so, this is safe
|
|
output = (stbi_uc *) stbi__malloc(n * z->s->img_x * z->s->img_y + 1);
|
|
if (!output) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); }
|
|
|
|
// now go ahead and resample
|
|
for (j=0; j < z->s->img_y; ++j) {
|
|
stbi_uc *out = output + n * z->s->img_x * j;
|
|
for (k=0; k < decode_n; ++k) {
|
|
stbi__resample *r = &res_comp[k];
|
|
int y_bot = r->ystep >= (r->vs >> 1);
|
|
coutput[k] = r->resample(z->img_comp[k].linebuf,
|
|
y_bot ? r->line1 : r->line0,
|
|
y_bot ? r->line0 : r->line1,
|
|
r->w_lores, r->hs);
|
|
if (++r->ystep >= r->vs) {
|
|
r->ystep = 0;
|
|
r->line0 = r->line1;
|
|
if (++r->ypos < z->img_comp[k].y)
|
|
r->line1 += z->img_comp[k].w2;
|
|
}
|
|
}
|
|
if (n >= 3) {
|
|
stbi_uc *y = coutput[0];
|
|
if (z->s->img_n == 3) {
|
|
if (z->rgb == 3) {
|
|
for (i=0; i < z->s->img_x; ++i) {
|
|
out[0] = y[i];
|
|
out[1] = coutput[1][i];
|
|
out[2] = coutput[2][i];
|
|
out[3] = 255;
|
|
out += n;
|
|
}
|
|
} else {
|
|
z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
|
|
}
|
|
} else
|
|
for (i=0; i < z->s->img_x; ++i) {
|
|
out[0] = out[1] = out[2] = y[i];
|
|
out[3] = 255; // not used if n==3
|
|
out += n;
|
|
}
|
|
} else {
|
|
stbi_uc *y = coutput[0];
|
|
if (n == 1)
|
|
for (i=0; i < z->s->img_x; ++i) out[i] = y[i];
|
|
else
|
|
for (i=0; i < z->s->img_x; ++i) *out++ = y[i], *out++ = 255;
|
|
}
|
|
}
|
|
stbi__cleanup_jpeg(z);
|
|
*out_x = z->s->img_x;
|
|
*out_y = z->s->img_y;
|
|
if (comp) *comp = z->s->img_n; // report original components, not output
|
|
return output;
|
|
}
|
|
}
|
|
|
|
static unsigned char *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char* result;
|
|
stbi__jpeg* j = (stbi__jpeg*) stbi__malloc(sizeof(stbi__jpeg));
|
|
j->s = s;
|
|
stbi__setup_jpeg(j);
|
|
result = load_jpeg_image(j, x,y,comp,req_comp);
|
|
STBI_FREE(j);
|
|
return result;
|
|
}
|
|
|
|
static int stbi__jpeg_test(stbi__context *s)
|
|
{
|
|
int r;
|
|
stbi__jpeg j;
|
|
j.s = s;
|
|
stbi__setup_jpeg(&j);
|
|
r = stbi__decode_jpeg_header(&j, STBI__SCAN_type);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
|
|
static int stbi__jpeg_info_raw(stbi__jpeg *j, int *x, int *y, int *comp)
|
|
{
|
|
if (!stbi__decode_jpeg_header(j, STBI__SCAN_header)) {
|
|
stbi__rewind( j->s );
|
|
return 0;
|
|
}
|
|
if (x) *x = j->s->img_x;
|
|
if (y) *y = j->s->img_y;
|
|
if (comp) *comp = j->s->img_n;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
int result;
|
|
stbi__jpeg* j = (stbi__jpeg*) (stbi__malloc(sizeof(stbi__jpeg)));
|
|
j->s = s;
|
|
result = stbi__jpeg_info_raw(j, x, y, comp);
|
|
STBI_FREE(j);
|
|
return result;
|
|
}
|
|
#endif
|
|
|
|
// public domain zlib decode v0.2 Sean Barrett 2006-11-18
|
|
// simple implementation
|
|
// - all input must be provided in an upfront buffer
|
|
// - all output is written to a single output buffer (can malloc/realloc)
|
|
// performance
|
|
// - fast huffman
|
|
|
|
#ifndef STBI_NO_ZLIB
|
|
|
|
// fast-way is faster to check than jpeg huffman, but slow way is slower
|
|
#define STBI__ZFAST_BITS 9 // accelerate all cases in default tables
|
|
#define STBI__ZFAST_MASK ((1 << STBI__ZFAST_BITS) - 1)
|
|
|
|
// zlib-style huffman encoding
|
|
// (jpegs packs from left, zlib from right, so can't share code)
|
|
typedef struct
|
|
{
|
|
stbi__uint16 fast[1 << STBI__ZFAST_BITS];
|
|
stbi__uint16 firstcode[16];
|
|
int maxcode[17];
|
|
stbi__uint16 firstsymbol[16];
|
|
stbi_uc size[288];
|
|
stbi__uint16 value[288];
|
|
} stbi__zhuffman;
|
|
|
|
stbi_inline static int stbi__bitreverse16(int n)
|
|
{
|
|
n = ((n & 0xAAAA) >> 1) | ((n & 0x5555) << 1);
|
|
n = ((n & 0xCCCC) >> 2) | ((n & 0x3333) << 2);
|
|
n = ((n & 0xF0F0) >> 4) | ((n & 0x0F0F) << 4);
|
|
n = ((n & 0xFF00) >> 8) | ((n & 0x00FF) << 8);
|
|
return n;
|
|
}
|
|
|
|
stbi_inline static int stbi__bit_reverse(int v, int bits)
|
|
{
|
|
STBI_ASSERT(bits <= 16);
|
|
// to bit reverse n bits, reverse 16 and shift
|
|
// e.g. 11 bits, bit reverse and shift away 5
|
|
return stbi__bitreverse16(v) >> (16-bits);
|
|
}
|
|
|
|
static int stbi__zbuild_huffman(stbi__zhuffman *z, stbi_uc *sizelist, int num)
|
|
{
|
|
int i,k=0;
|
|
int code, next_code[16], sizes[17];
|
|
|
|
// DEFLATE spec for generating codes
|
|
memset(sizes, 0, sizeof(sizes));
|
|
memset(z->fast, 0, sizeof(z->fast));
|
|
for (i=0; i < num; ++i)
|
|
++sizes[sizelist[i]];
|
|
sizes[0] = 0;
|
|
for (i=1; i < 16; ++i)
|
|
if (sizes[i] > (1 << i))
|
|
return stbi__err("bad sizes", "Corrupt PNG");
|
|
code = 0;
|
|
for (i=1; i < 16; ++i) {
|
|
next_code[i] = code;
|
|
z->firstcode[i] = (stbi__uint16) code;
|
|
z->firstsymbol[i] = (stbi__uint16) k;
|
|
code = (code + sizes[i]);
|
|
if (sizes[i])
|
|
if (code-1 >= (1 << i)) return stbi__err("bad codelengths","Corrupt PNG");
|
|
z->maxcode[i] = code << (16-i); // preshift for inner loop
|
|
code <<= 1;
|
|
k += sizes[i];
|
|
}
|
|
z->maxcode[16] = 0x10000; // sentinel
|
|
for (i=0; i < num; ++i) {
|
|
int s = sizelist[i];
|
|
if (s) {
|
|
int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s];
|
|
stbi__uint16 fastv = (stbi__uint16) ((s << 9) | i);
|
|
z->size [c] = (stbi_uc ) s;
|
|
z->value[c] = (stbi__uint16) i;
|
|
if (s <= STBI__ZFAST_BITS) {
|
|
int j = stbi__bit_reverse(next_code[s],s);
|
|
while (j < (1 << STBI__ZFAST_BITS)) {
|
|
z->fast[j] = fastv;
|
|
j += (1 << s);
|
|
}
|
|
}
|
|
++next_code[s];
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// zlib-from-memory implementation for PNG reading
|
|
// because PNG allows splitting the zlib stream arbitrarily,
|
|
// and it's annoying structurally to have PNG call ZLIB call PNG,
|
|
// we require PNG read all the IDATs and combine them into a single
|
|
// memory buffer
|
|
|
|
typedef struct
|
|
{
|
|
stbi_uc *zbuffer, *zbuffer_end;
|
|
int num_bits;
|
|
stbi__uint32 code_buffer;
|
|
|
|
char *zout;
|
|
char *zout_start;
|
|
char *zout_end;
|
|
int z_expandable;
|
|
|
|
stbi__zhuffman z_length, z_distance;
|
|
} stbi__zbuf;
|
|
|
|
stbi_inline static stbi_uc stbi__zget8(stbi__zbuf *z)
|
|
{
|
|
if (z->zbuffer >= z->zbuffer_end) return 0;
|
|
return *z->zbuffer++;
|
|
}
|
|
|
|
static void stbi__fill_bits(stbi__zbuf *z)
|
|
{
|
|
do {
|
|
STBI_ASSERT(z->code_buffer < (1U << z->num_bits));
|
|
z->code_buffer |= (unsigned int) stbi__zget8(z) << z->num_bits;
|
|
z->num_bits += 8;
|
|
} while (z->num_bits <= 24);
|
|
}
|
|
|
|
stbi_inline static unsigned int stbi__zreceive(stbi__zbuf *z, int n)
|
|
{
|
|
unsigned int k;
|
|
if (z->num_bits < n) stbi__fill_bits(z);
|
|
k = z->code_buffer & ((1 << n) - 1);
|
|
z->code_buffer >>= n;
|
|
z->num_bits -= n;
|
|
return k;
|
|
}
|
|
|
|
static int stbi__zhuffman_decode_slowpath(stbi__zbuf *a, stbi__zhuffman *z)
|
|
{
|
|
int b,s,k;
|
|
// not resolved by fast table, so compute it the slow way
|
|
// use jpeg approach, which requires MSbits at top
|
|
k = stbi__bit_reverse(a->code_buffer, 16);
|
|
for (s=STBI__ZFAST_BITS+1; ; ++s)
|
|
if (k < z->maxcode[s])
|
|
break;
|
|
if (s == 16) return -1; // invalid code!
|
|
// code size is s, so:
|
|
b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s];
|
|
STBI_ASSERT(z->size[b] == s);
|
|
a->code_buffer >>= s;
|
|
a->num_bits -= s;
|
|
return z->value[b];
|
|
}
|
|
|
|
stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z)
|
|
{
|
|
int b,s;
|
|
if (a->num_bits < 16) stbi__fill_bits(a);
|
|
b = z->fast[a->code_buffer & STBI__ZFAST_MASK];
|
|
if (b) {
|
|
s = b >> 9;
|
|
a->code_buffer >>= s;
|
|
a->num_bits -= s;
|
|
return b & 511;
|
|
}
|
|
return stbi__zhuffman_decode_slowpath(a, z);
|
|
}
|
|
|
|
static int stbi__zexpand(stbi__zbuf *z, char *zout, int n) // need to make room for n bytes
|
|
{
|
|
char *q;
|
|
int cur, limit, old_limit;
|
|
z->zout = zout;
|
|
if (!z->z_expandable) return stbi__err("output buffer limit","Corrupt PNG");
|
|
cur = (int) (z->zout - z->zout_start);
|
|
limit = old_limit = (int) (z->zout_end - z->zout_start);
|
|
while (cur + n > limit)
|
|
limit *= 2;
|
|
q = (char *) STBI_REALLOC_SIZED(z->zout_start, old_limit, limit);
|
|
STBI_NOTUSED(old_limit);
|
|
if (q == NULL) return stbi__err("outofmem", "Out of memory");
|
|
z->zout_start = q;
|
|
z->zout = q + cur;
|
|
z->zout_end = q + limit;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__zlength_base[31] = {
|
|
3,4,5,6,7,8,9,10,11,13,
|
|
15,17,19,23,27,31,35,43,51,59,
|
|
67,83,99,115,131,163,195,227,258,0,0 };
|
|
|
|
static int stbi__zlength_extra[31]=
|
|
{ 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 };
|
|
|
|
static int stbi__zdist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,
|
|
257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
|
|
|
|
static int stbi__zdist_extra[32] =
|
|
{ 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
|
|
|
|
static int stbi__parse_huffman_block(stbi__zbuf *a)
|
|
{
|
|
char *zout = a->zout;
|
|
for(;;) {
|
|
int z = stbi__zhuffman_decode(a, &a->z_length);
|
|
if (z < 256) {
|
|
if (z < 0) return stbi__err("bad huffman code","Corrupt PNG"); // error in huffman codes
|
|
if (zout >= a->zout_end) {
|
|
if (!stbi__zexpand(a, zout, 1)) return 0;
|
|
zout = a->zout;
|
|
}
|
|
*zout++ = (char) z;
|
|
} else {
|
|
stbi_uc *p;
|
|
int len,dist;
|
|
if (z == 256) {
|
|
a->zout = zout;
|
|
return 1;
|
|
}
|
|
z -= 257;
|
|
len = stbi__zlength_base[z];
|
|
if (stbi__zlength_extra[z]) len += stbi__zreceive(a, stbi__zlength_extra[z]);
|
|
z = stbi__zhuffman_decode(a, &a->z_distance);
|
|
if (z < 0) return stbi__err("bad huffman code","Corrupt PNG");
|
|
dist = stbi__zdist_base[z];
|
|
if (stbi__zdist_extra[z]) dist += stbi__zreceive(a, stbi__zdist_extra[z]);
|
|
if (zout - a->zout_start < dist) return stbi__err("bad dist","Corrupt PNG");
|
|
if (zout + len > a->zout_end) {
|
|
if (!stbi__zexpand(a, zout, len)) return 0;
|
|
zout = a->zout;
|
|
}
|
|
p = (stbi_uc *) (zout - dist);
|
|
if (dist == 1) { // run of one byte; common in images.
|
|
stbi_uc v = *p;
|
|
if (len) { do *zout++ = v; while (--len); }
|
|
} else {
|
|
if (len) { do *zout++ = *p++; while (--len); }
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int stbi__compute_huffman_codes(stbi__zbuf *a)
|
|
{
|
|
static stbi_uc length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 };
|
|
stbi__zhuffman z_codelength;
|
|
stbi_uc lencodes[286+32+137];//padding for maximum single op
|
|
stbi_uc codelength_sizes[19];
|
|
int i,n;
|
|
|
|
int hlit = stbi__zreceive(a,5) + 257;
|
|
int hdist = stbi__zreceive(a,5) + 1;
|
|
int hclen = stbi__zreceive(a,4) + 4;
|
|
|
|
memset(codelength_sizes, 0, sizeof(codelength_sizes));
|
|
for (i=0; i < hclen; ++i) {
|
|
int s = stbi__zreceive(a,3);
|
|
codelength_sizes[length_dezigzag[i]] = (stbi_uc) s;
|
|
}
|
|
if (!stbi__zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0;
|
|
|
|
n = 0;
|
|
while (n < hlit + hdist) {
|
|
int c = stbi__zhuffman_decode(a, &z_codelength);
|
|
if (c < 0 || c >= 19) return stbi__err("bad codelengths", "Corrupt PNG");
|
|
if (c < 16)
|
|
lencodes[n++] = (stbi_uc) c;
|
|
else if (c == 16) {
|
|
c = stbi__zreceive(a,2)+3;
|
|
memset(lencodes+n, lencodes[n-1], c);
|
|
n += c;
|
|
} else if (c == 17) {
|
|
c = stbi__zreceive(a,3)+3;
|
|
memset(lencodes+n, 0, c);
|
|
n += c;
|
|
} else {
|
|
STBI_ASSERT(c == 18);
|
|
c = stbi__zreceive(a,7)+11;
|
|
memset(lencodes+n, 0, c);
|
|
n += c;
|
|
}
|
|
}
|
|
if (n != hlit+hdist) return stbi__err("bad codelengths","Corrupt PNG");
|
|
if (!stbi__zbuild_huffman(&a->z_length, lencodes, hlit)) return 0;
|
|
if (!stbi__zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__parse_uncompressed_block(stbi__zbuf *a)
|
|
{
|
|
stbi_uc header[4];
|
|
int len,nlen,k;
|
|
if (a->num_bits & 7)
|
|
stbi__zreceive(a, a->num_bits & 7); // discard
|
|
// drain the bit-packed data into header
|
|
k = 0;
|
|
while (a->num_bits > 0) {
|
|
header[k++] = (stbi_uc) (a->code_buffer & 255); // suppress MSVC run-time check
|
|
a->code_buffer >>= 8;
|
|
a->num_bits -= 8;
|
|
}
|
|
STBI_ASSERT(a->num_bits == 0);
|
|
// now fill header the normal way
|
|
while (k < 4)
|
|
header[k++] = stbi__zget8(a);
|
|
len = header[1] * 256 + header[0];
|
|
nlen = header[3] * 256 + header[2];
|
|
if (nlen != (len ^ 0xffff)) return stbi__err("zlib corrupt","Corrupt PNG");
|
|
if (a->zbuffer + len > a->zbuffer_end) return stbi__err("read past buffer","Corrupt PNG");
|
|
if (a->zout + len > a->zout_end)
|
|
if (!stbi__zexpand(a, a->zout, len)) return 0;
|
|
memcpy(a->zout, a->zbuffer, len);
|
|
a->zbuffer += len;
|
|
a->zout += len;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__parse_zlib_header(stbi__zbuf *a)
|
|
{
|
|
int cmf = stbi__zget8(a);
|
|
int cm = cmf & 15;
|
|
/* int cinfo = cmf >> 4; */
|
|
int flg = stbi__zget8(a);
|
|
if ((cmf*256+flg) % 31 != 0) return stbi__err("bad zlib header","Corrupt PNG"); // zlib spec
|
|
if (flg & 32) return stbi__err("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png
|
|
if (cm != 8) return stbi__err("bad compression","Corrupt PNG"); // DEFLATE required for png
|
|
// window = 1 << (8 + cinfo)... but who cares, we fully buffer output
|
|
return 1;
|
|
}
|
|
|
|
// @TODO: should statically initialize these for optimal thread safety
|
|
static stbi_uc stbi__zdefault_length[288], stbi__zdefault_distance[32];
|
|
static void stbi__init_zdefaults(void)
|
|
{
|
|
int i; // use <= to match clearly with spec
|
|
for (i=0; i <= 143; ++i) stbi__zdefault_length[i] = 8;
|
|
for ( ; i <= 255; ++i) stbi__zdefault_length[i] = 9;
|
|
for ( ; i <= 279; ++i) stbi__zdefault_length[i] = 7;
|
|
for ( ; i <= 287; ++i) stbi__zdefault_length[i] = 8;
|
|
|
|
for (i=0; i <= 31; ++i) stbi__zdefault_distance[i] = 5;
|
|
}
|
|
|
|
static int stbi__parse_zlib(stbi__zbuf *a, int parse_header)
|
|
{
|
|
int final, type;
|
|
if (parse_header)
|
|
if (!stbi__parse_zlib_header(a)) return 0;
|
|
a->num_bits = 0;
|
|
a->code_buffer = 0;
|
|
do {
|
|
final = stbi__zreceive(a,1);
|
|
type = stbi__zreceive(a,2);
|
|
if (type == 0) {
|
|
if (!stbi__parse_uncompressed_block(a)) return 0;
|
|
} else if (type == 3) {
|
|
return 0;
|
|
} else {
|
|
if (type == 1) {
|
|
// use fixed code lengths
|
|
if (!stbi__zdefault_distance[31]) stbi__init_zdefaults();
|
|
if (!stbi__zbuild_huffman(&a->z_length , stbi__zdefault_length , 288)) return 0;
|
|
if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance, 32)) return 0;
|
|
} else {
|
|
if (!stbi__compute_huffman_codes(a)) return 0;
|
|
}
|
|
if (!stbi__parse_huffman_block(a)) return 0;
|
|
}
|
|
} while (!final);
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__do_zlib(stbi__zbuf *a, char *obuf, int olen, int exp, int parse_header)
|
|
{
|
|
a->zout_start = obuf;
|
|
a->zout = obuf;
|
|
a->zout_end = obuf + olen;
|
|
a->z_expandable = exp;
|
|
|
|
return stbi__parse_zlib(a, parse_header);
|
|
}
|
|
|
|
STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen)
|
|
{
|
|
stbi__zbuf a;
|
|
char *p = (char *) stbi__malloc(initial_size);
|
|
if (p == NULL) return NULL;
|
|
a.zbuffer = (stbi_uc *) buffer;
|
|
a.zbuffer_end = (stbi_uc *) buffer + len;
|
|
if (stbi__do_zlib(&a, p, initial_size, 1, 1)) {
|
|
if (outlen) *outlen = (int) (a.zout - a.zout_start);
|
|
return a.zout_start;
|
|
} else {
|
|
STBI_FREE(a.zout_start);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
STBIDEF char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen)
|
|
{
|
|
return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen);
|
|
}
|
|
|
|
STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header)
|
|
{
|
|
stbi__zbuf a;
|
|
char *p = (char *) stbi__malloc(initial_size);
|
|
if (p == NULL) return NULL;
|
|
a.zbuffer = (stbi_uc *) buffer;
|
|
a.zbuffer_end = (stbi_uc *) buffer + len;
|
|
if (stbi__do_zlib(&a, p, initial_size, 1, parse_header)) {
|
|
if (outlen) *outlen = (int) (a.zout - a.zout_start);
|
|
return a.zout_start;
|
|
} else {
|
|
STBI_FREE(a.zout_start);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen)
|
|
{
|
|
stbi__zbuf a;
|
|
a.zbuffer = (stbi_uc *) ibuffer;
|
|
a.zbuffer_end = (stbi_uc *) ibuffer + ilen;
|
|
if (stbi__do_zlib(&a, obuffer, olen, 0, 1))
|
|
return (int) (a.zout - a.zout_start);
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen)
|
|
{
|
|
stbi__zbuf a;
|
|
char *p = (char *) stbi__malloc(16384);
|
|
if (p == NULL) return NULL;
|
|
a.zbuffer = (stbi_uc *) buffer;
|
|
a.zbuffer_end = (stbi_uc *) buffer+len;
|
|
if (stbi__do_zlib(&a, p, 16384, 1, 0)) {
|
|
if (outlen) *outlen = (int) (a.zout - a.zout_start);
|
|
return a.zout_start;
|
|
} else {
|
|
STBI_FREE(a.zout_start);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen)
|
|
{
|
|
stbi__zbuf a;
|
|
a.zbuffer = (stbi_uc *) ibuffer;
|
|
a.zbuffer_end = (stbi_uc *) ibuffer + ilen;
|
|
if (stbi__do_zlib(&a, obuffer, olen, 0, 0))
|
|
return (int) (a.zout - a.zout_start);
|
|
else
|
|
return -1;
|
|
}
|
|
#endif
|
|
|
|
// public domain "baseline" PNG decoder v0.10 Sean Barrett 2006-11-18
|
|
// simple implementation
|
|
// - only 8-bit samples
|
|
// - no CRC checking
|
|
// - allocates lots of intermediate memory
|
|
// - avoids problem of streaming data between subsystems
|
|
// - avoids explicit window management
|
|
// performance
|
|
// - uses stb_zlib, a PD zlib implementation with fast huffman decoding
|
|
|
|
#ifndef STBI_NO_PNG
|
|
typedef struct
|
|
{
|
|
stbi__uint32 length;
|
|
stbi__uint32 type;
|
|
} stbi__pngchunk;
|
|
|
|
static stbi__pngchunk stbi__get_chunk_header(stbi__context *s)
|
|
{
|
|
stbi__pngchunk c;
|
|
c.length = stbi__get32be(s);
|
|
c.type = stbi__get32be(s);
|
|
return c;
|
|
}
|
|
|
|
static int stbi__check_png_header(stbi__context *s)
|
|
{
|
|
static stbi_uc png_sig[8] = { 137,80,78,71,13,10,26,10 };
|
|
int i;
|
|
for (i=0; i < 8; ++i)
|
|
if (stbi__get8(s) != png_sig[i]) return stbi__err("bad png sig","Not a PNG");
|
|
return 1;
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
stbi__context *s;
|
|
stbi_uc *idata, *expanded, *out;
|
|
int depth;
|
|
} stbi__png;
|
|
|
|
|
|
enum {
|
|
STBI__F_none=0,
|
|
STBI__F_sub=1,
|
|
STBI__F_up=2,
|
|
STBI__F_avg=3,
|
|
STBI__F_paeth=4,
|
|
// synthetic filters used for first scanline to avoid needing a dummy row of 0s
|
|
STBI__F_avg_first,
|
|
STBI__F_paeth_first
|
|
};
|
|
|
|
static stbi_uc first_row_filter[5] =
|
|
{
|
|
STBI__F_none,
|
|
STBI__F_sub,
|
|
STBI__F_none,
|
|
STBI__F_avg_first,
|
|
STBI__F_paeth_first
|
|
};
|
|
|
|
static int stbi__paeth(int a, int b, int c)
|
|
{
|
|
int p = a + b - c;
|
|
int pa = abs(p-a);
|
|
int pb = abs(p-b);
|
|
int pc = abs(p-c);
|
|
if (pa <= pb && pa <= pc) return a;
|
|
if (pb <= pc) return b;
|
|
return c;
|
|
}
|
|
|
|
static stbi_uc stbi__depth_scale_table[9] = { 0, 0xff, 0x55, 0, 0x11, 0,0,0, 0x01 };
|
|
|
|
// create the png data from post-deflated data
|
|
static int stbi__create_png_image_raw(stbi__png *a, stbi_uc *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y, int depth, int color)
|
|
{
|
|
int bytes = (depth == 16? 2 : 1);
|
|
stbi__context *s = a->s;
|
|
stbi__uint32 i,j,stride = x*out_n*bytes;
|
|
stbi__uint32 img_len, img_width_bytes;
|
|
int k;
|
|
int img_n = s->img_n; // copy it into a local for later
|
|
|
|
int output_bytes = out_n*bytes;
|
|
int filter_bytes = img_n*bytes;
|
|
int width = x;
|
|
|
|
STBI_ASSERT(out_n == s->img_n || out_n == s->img_n+1);
|
|
a->out = (stbi_uc *) stbi__malloc(x * y * output_bytes); // extra bytes to write off the end into
|
|
if (!a->out) return stbi__err("outofmem", "Out of memory");
|
|
|
|
img_width_bytes = (((img_n * x * depth) + 7) >> 3);
|
|
img_len = (img_width_bytes + 1) * y;
|
|
if (s->img_x == x && s->img_y == y) {
|
|
if (raw_len != img_len) return stbi__err("not enough pixels","Corrupt PNG");
|
|
} else { // interlaced:
|
|
if (raw_len < img_len) return stbi__err("not enough pixels","Corrupt PNG");
|
|
}
|
|
|
|
for (j=0; j < y; ++j) {
|
|
stbi_uc *cur = a->out + stride*j;
|
|
stbi_uc *prior = cur - stride;
|
|
int filter = *raw++;
|
|
|
|
if (filter > 4)
|
|
return stbi__err("invalid filter","Corrupt PNG");
|
|
|
|
if (depth < 8) {
|
|
STBI_ASSERT(img_width_bytes <= x);
|
|
cur += x*out_n - img_width_bytes; // store output to the rightmost img_len bytes, so we can decode in place
|
|
filter_bytes = 1;
|
|
width = img_width_bytes;
|
|
}
|
|
|
|
// if first row, use special filter that doesn't sample previous row
|
|
if (j == 0) filter = first_row_filter[filter];
|
|
|
|
// handle first byte explicitly
|
|
for (k=0; k < filter_bytes; ++k) {
|
|
switch (filter) {
|
|
case STBI__F_none : cur[k] = raw[k]; break;
|
|
case STBI__F_sub : cur[k] = raw[k]; break;
|
|
case STBI__F_up : cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
|
|
case STBI__F_avg : cur[k] = STBI__BYTECAST(raw[k] + (prior[k]>>1)); break;
|
|
case STBI__F_paeth : cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(0,prior[k],0)); break;
|
|
case STBI__F_avg_first : cur[k] = raw[k]; break;
|
|
case STBI__F_paeth_first: cur[k] = raw[k]; break;
|
|
}
|
|
}
|
|
|
|
if (depth == 8) {
|
|
if (img_n != out_n)
|
|
cur[img_n] = 255; // first pixel
|
|
raw += img_n;
|
|
cur += out_n;
|
|
prior += out_n;
|
|
} else if (depth == 16) {
|
|
if (img_n != out_n) {
|
|
cur[filter_bytes] = 255; // first pixel top byte
|
|
cur[filter_bytes+1] = 255; // first pixel bottom byte
|
|
}
|
|
raw += filter_bytes;
|
|
cur += output_bytes;
|
|
prior += output_bytes;
|
|
} else {
|
|
raw += 1;
|
|
cur += 1;
|
|
prior += 1;
|
|
}
|
|
|
|
// this is a little gross, so that we don't switch per-pixel or per-component
|
|
if (depth < 8 || img_n == out_n) {
|
|
int nk = (width - 1)*filter_bytes;
|
|
#define CASE(f) \
|
|
case f: \
|
|
for (k=0; k < nk; ++k)
|
|
switch (filter) {
|
|
// "none" filter turns into a memcpy here; make that explicit.
|
|
case STBI__F_none: memcpy(cur, raw, nk); break;
|
|
CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k-filter_bytes]); break;
|
|
CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
|
|
CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-filter_bytes])>>1)); break;
|
|
CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],prior[k],prior[k-filter_bytes])); break;
|
|
CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k-filter_bytes] >> 1)); break;
|
|
CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],0,0)); break;
|
|
}
|
|
#undef CASE
|
|
raw += nk;
|
|
} else {
|
|
STBI_ASSERT(img_n+1 == out_n);
|
|
#define CASE(f) \
|
|
case f: \
|
|
for (i=x-1; i >= 1; --i, cur[filter_bytes]=255,raw+=filter_bytes,cur+=output_bytes,prior+=output_bytes) \
|
|
for (k=0; k < filter_bytes; ++k)
|
|
switch (filter) {
|
|
CASE(STBI__F_none) cur[k] = raw[k]; break;
|
|
CASE(STBI__F_sub) cur[k] = STBI__BYTECAST(raw[k] + cur[k- output_bytes]); break;
|
|
CASE(STBI__F_up) cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
|
|
CASE(STBI__F_avg) cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k- output_bytes])>>1)); break;
|
|
CASE(STBI__F_paeth) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],prior[k],prior[k- output_bytes])); break;
|
|
CASE(STBI__F_avg_first) cur[k] = STBI__BYTECAST(raw[k] + (cur[k- output_bytes] >> 1)); break;
|
|
CASE(STBI__F_paeth_first) cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],0,0)); break;
|
|
}
|
|
#undef CASE
|
|
|
|
// the loop above sets the high byte of the pixels' alpha, but for
|
|
// 16 bit png files we also need the low byte set. we'll do that here.
|
|
if (depth == 16) {
|
|
cur = a->out + stride*j; // start at the beginning of the row again
|
|
for (i=0; i < x; ++i,cur+=output_bytes) {
|
|
cur[filter_bytes+1] = 255;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// we make a separate pass to expand bits to pixels; for performance,
|
|
// this could run two scanlines behind the above code, so it won't
|
|
// intefere with filtering but will still be in the cache.
|
|
if (depth < 8) {
|
|
for (j=0; j < y; ++j) {
|
|
stbi_uc *cur = a->out + stride*j;
|
|
stbi_uc *in = a->out + stride*j + x*out_n - img_width_bytes;
|
|
// unpack 1/2/4-bit into a 8-bit buffer. allows us to keep the common 8-bit path optimal at minimal cost for 1/2/4-bit
|
|
// png guarante byte alignment, if width is not multiple of 8/4/2 we'll decode dummy trailing data that will be skipped in the later loop
|
|
stbi_uc scale = (color == 0) ? stbi__depth_scale_table[depth] : 1; // scale grayscale values to 0..255 range
|
|
|
|
// note that the final byte might overshoot and write more data than desired.
|
|
// we can allocate enough data that this never writes out of memory, but it
|
|
// could also overwrite the next scanline. can it overwrite non-empty data
|
|
// on the next scanline? yes, consider 1-pixel-wide scanlines with 1-bit-per-pixel.
|
|
// so we need to explicitly clamp the final ones
|
|
|
|
if (depth == 4) {
|
|
for (k=x*img_n; k >= 2; k-=2, ++in) {
|
|
*cur++ = scale * ((*in >> 4) );
|
|
*cur++ = scale * ((*in ) & 0x0f);
|
|
}
|
|
if (k > 0) *cur++ = scale * ((*in >> 4) );
|
|
} else if (depth == 2) {
|
|
for (k=x*img_n; k >= 4; k-=4, ++in) {
|
|
*cur++ = scale * ((*in >> 6) );
|
|
*cur++ = scale * ((*in >> 4) & 0x03);
|
|
*cur++ = scale * ((*in >> 2) & 0x03);
|
|
*cur++ = scale * ((*in ) & 0x03);
|
|
}
|
|
if (k > 0) *cur++ = scale * ((*in >> 6) );
|
|
if (k > 1) *cur++ = scale * ((*in >> 4) & 0x03);
|
|
if (k > 2) *cur++ = scale * ((*in >> 2) & 0x03);
|
|
} else if (depth == 1) {
|
|
for (k=x*img_n; k >= 8; k-=8, ++in) {
|
|
*cur++ = scale * ((*in >> 7) );
|
|
*cur++ = scale * ((*in >> 6) & 0x01);
|
|
*cur++ = scale * ((*in >> 5) & 0x01);
|
|
*cur++ = scale * ((*in >> 4) & 0x01);
|
|
*cur++ = scale * ((*in >> 3) & 0x01);
|
|
*cur++ = scale * ((*in >> 2) & 0x01);
|
|
*cur++ = scale * ((*in >> 1) & 0x01);
|
|
*cur++ = scale * ((*in ) & 0x01);
|
|
}
|
|
if (k > 0) *cur++ = scale * ((*in >> 7) );
|
|
if (k > 1) *cur++ = scale * ((*in >> 6) & 0x01);
|
|
if (k > 2) *cur++ = scale * ((*in >> 5) & 0x01);
|
|
if (k > 3) *cur++ = scale * ((*in >> 4) & 0x01);
|
|
if (k > 4) *cur++ = scale * ((*in >> 3) & 0x01);
|
|
if (k > 5) *cur++ = scale * ((*in >> 2) & 0x01);
|
|
if (k > 6) *cur++ = scale * ((*in >> 1) & 0x01);
|
|
}
|
|
if (img_n != out_n) {
|
|
int q;
|
|
// insert alpha = 255
|
|
cur = a->out + stride*j;
|
|
if (img_n == 1) {
|
|
for (q=x-1; q >= 0; --q) {
|
|
cur[q*2+1] = 255;
|
|
cur[q*2+0] = cur[q];
|
|
}
|
|
} else {
|
|
STBI_ASSERT(img_n == 3);
|
|
for (q=x-1; q >= 0; --q) {
|
|
cur[q*4+3] = 255;
|
|
cur[q*4+2] = cur[q*3+2];
|
|
cur[q*4+1] = cur[q*3+1];
|
|
cur[q*4+0] = cur[q*3+0];
|
|
}
|
|
}
|
|
}
|
|
}
|
|
} else if (depth == 16) {
|
|
// force the image data from big-endian to platform-native.
|
|
// this is done in a separate pass due to the decoding relying
|
|
// on the data being untouched, but could probably be done
|
|
// per-line during decode if care is taken.
|
|
stbi_uc *cur = a->out;
|
|
stbi__uint16 *cur16 = (stbi__uint16*)cur;
|
|
|
|
for(i=0; i < x*y*out_n; ++i,cur16++,cur+=2) {
|
|
*cur16 = (cur[0] << 8) | cur[1];
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__create_png_image(stbi__png *a, stbi_uc *image_data, stbi__uint32 image_data_len, int out_n, int depth, int color, int interlaced)
|
|
{
|
|
stbi_uc *final;
|
|
int p;
|
|
if (!interlaced)
|
|
return stbi__create_png_image_raw(a, image_data, image_data_len, out_n, a->s->img_x, a->s->img_y, depth, color);
|
|
|
|
// de-interlacing
|
|
final = (stbi_uc *) stbi__malloc(a->s->img_x * a->s->img_y * out_n);
|
|
for (p=0; p < 7; ++p) {
|
|
int xorig[] = { 0,4,0,2,0,1,0 };
|
|
int yorig[] = { 0,0,4,0,2,0,1 };
|
|
int xspc[] = { 8,8,4,4,2,2,1 };
|
|
int yspc[] = { 8,8,8,4,4,2,2 };
|
|
int i,j,x,y;
|
|
// pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1
|
|
x = (a->s->img_x - xorig[p] + xspc[p]-1) / xspc[p];
|
|
y = (a->s->img_y - yorig[p] + yspc[p]-1) / yspc[p];
|
|
if (x && y) {
|
|
stbi__uint32 img_len = ((((a->s->img_n * x * depth) + 7) >> 3) + 1) * y;
|
|
if (!stbi__create_png_image_raw(a, image_data, image_data_len, out_n, x, y, depth, color)) {
|
|
STBI_FREE(final);
|
|
return 0;
|
|
}
|
|
for (j=0; j < y; ++j) {
|
|
for (i=0; i < x; ++i) {
|
|
int out_y = j*yspc[p]+yorig[p];
|
|
int out_x = i*xspc[p]+xorig[p];
|
|
memcpy(final + out_y*a->s->img_x*out_n + out_x*out_n,
|
|
a->out + (j*x+i)*out_n, out_n);
|
|
}
|
|
}
|
|
STBI_FREE(a->out);
|
|
image_data += img_len;
|
|
image_data_len -= img_len;
|
|
}
|
|
}
|
|
a->out = final;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__compute_transparency(stbi__png *z, stbi_uc tc[3], int out_n)
|
|
{
|
|
stbi__context *s = z->s;
|
|
stbi__uint32 i, pixel_count = s->img_x * s->img_y;
|
|
stbi_uc *p = z->out;
|
|
|
|
// compute color-based transparency, assuming we've
|
|
// already got 255 as the alpha value in the output
|
|
STBI_ASSERT(out_n == 2 || out_n == 4);
|
|
|
|
if (out_n == 2) {
|
|
for (i=0; i < pixel_count; ++i) {
|
|
p[1] = (p[0] == tc[0] ? 0 : 255);
|
|
p += 2;
|
|
}
|
|
} else {
|
|
for (i=0; i < pixel_count; ++i) {
|
|
if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2])
|
|
p[3] = 0;
|
|
p += 4;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__compute_transparency16(stbi__png *z, stbi__uint16 tc[3], int out_n)
|
|
{
|
|
stbi__context *s = z->s;
|
|
stbi__uint32 i, pixel_count = s->img_x * s->img_y;
|
|
stbi__uint16 *p = (stbi__uint16*) z->out;
|
|
|
|
// compute color-based transparency, assuming we've
|
|
// already got 65535 as the alpha value in the output
|
|
STBI_ASSERT(out_n == 2 || out_n == 4);
|
|
|
|
if (out_n == 2) {
|
|
for (i = 0; i < pixel_count; ++i) {
|
|
p[1] = (p[0] == tc[0] ? 0 : 65535);
|
|
p += 2;
|
|
}
|
|
} else {
|
|
for (i = 0; i < pixel_count; ++i) {
|
|
if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2])
|
|
p[3] = 0;
|
|
p += 4;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__expand_png_palette(stbi__png *a, stbi_uc *palette, int len, int pal_img_n)
|
|
{
|
|
stbi__uint32 i, pixel_count = a->s->img_x * a->s->img_y;
|
|
stbi_uc *p, *temp_out, *orig = a->out;
|
|
|
|
p = (stbi_uc *) stbi__malloc(pixel_count * pal_img_n);
|
|
if (p == NULL) return stbi__err("outofmem", "Out of memory");
|
|
|
|
// between here and free(out) below, exitting would leak
|
|
temp_out = p;
|
|
|
|
if (pal_img_n == 3) {
|
|
for (i=0; i < pixel_count; ++i) {
|
|
int n = orig[i]*4;
|
|
p[0] = palette[n ];
|
|
p[1] = palette[n+1];
|
|
p[2] = palette[n+2];
|
|
p += 3;
|
|
}
|
|
} else {
|
|
for (i=0; i < pixel_count; ++i) {
|
|
int n = orig[i]*4;
|
|
p[0] = palette[n ];
|
|
p[1] = palette[n+1];
|
|
p[2] = palette[n+2];
|
|
p[3] = palette[n+3];
|
|
p += 4;
|
|
}
|
|
}
|
|
STBI_FREE(a->out);
|
|
a->out = temp_out;
|
|
|
|
STBI_NOTUSED(len);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__reduce_png(stbi__png *p)
|
|
{
|
|
int i;
|
|
int img_len = p->s->img_x * p->s->img_y * p->s->img_out_n;
|
|
stbi_uc *reduced;
|
|
stbi__uint16 *orig = (stbi__uint16*)p->out;
|
|
|
|
if (p->depth != 16) return 1; // don't need to do anything if not 16-bit data
|
|
|
|
reduced = (stbi_uc *)stbi__malloc(img_len);
|
|
if (p == NULL) return stbi__err("outofmem", "Out of memory");
|
|
|
|
for (i = 0; i < img_len; ++i) reduced[i] = (stbi_uc)((orig[i] >> 8) & 0xFF); // top half of each byte is a decent approx of 16->8 bit scaling
|
|
|
|
p->out = reduced;
|
|
STBI_FREE(orig);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__unpremultiply_on_load = 0;
|
|
static int stbi__de_iphone_flag = 0;
|
|
|
|
STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply)
|
|
{
|
|
stbi__unpremultiply_on_load = flag_true_if_should_unpremultiply;
|
|
}
|
|
|
|
STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert)
|
|
{
|
|
stbi__de_iphone_flag = flag_true_if_should_convert;
|
|
}
|
|
|
|
static void stbi__de_iphone(stbi__png *z)
|
|
{
|
|
stbi__context *s = z->s;
|
|
stbi__uint32 i, pixel_count = s->img_x * s->img_y;
|
|
stbi_uc *p = z->out;
|
|
|
|
if (s->img_out_n == 3) { // convert bgr to rgb
|
|
for (i=0; i < pixel_count; ++i) {
|
|
stbi_uc t = p[0];
|
|
p[0] = p[2];
|
|
p[2] = t;
|
|
p += 3;
|
|
}
|
|
} else {
|
|
STBI_ASSERT(s->img_out_n == 4);
|
|
if (stbi__unpremultiply_on_load) {
|
|
// convert bgr to rgb and unpremultiply
|
|
for (i=0; i < pixel_count; ++i) {
|
|
stbi_uc a = p[3];
|
|
stbi_uc t = p[0];
|
|
if (a) {
|
|
p[0] = p[2] * 255 / a;
|
|
p[1] = p[1] * 255 / a;
|
|
p[2] = t * 255 / a;
|
|
} else {
|
|
p[0] = p[2];
|
|
p[2] = t;
|
|
}
|
|
p += 4;
|
|
}
|
|
} else {
|
|
// convert bgr to rgb
|
|
for (i=0; i < pixel_count; ++i) {
|
|
stbi_uc t = p[0];
|
|
p[0] = p[2];
|
|
p[2] = t;
|
|
p += 4;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#define STBI__PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
|
|
|
|
static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp)
|
|
{
|
|
stbi_uc palette[1024], pal_img_n=0;
|
|
stbi_uc has_trans=0, tc[3];
|
|
stbi__uint16 tc16[3];
|
|
stbi__uint32 ioff=0, idata_limit=0, i, pal_len=0;
|
|
int first=1,k,interlace=0, color=0, is_iphone=0;
|
|
stbi__context *s = z->s;
|
|
|
|
z->expanded = NULL;
|
|
z->idata = NULL;
|
|
z->out = NULL;
|
|
|
|
if (!stbi__check_png_header(s)) return 0;
|
|
|
|
if (scan == STBI__SCAN_type) return 1;
|
|
|
|
for (;;) {
|
|
stbi__pngchunk c = stbi__get_chunk_header(s);
|
|
switch (c.type) {
|
|
case STBI__PNG_TYPE('C','g','B','I'):
|
|
is_iphone = 1;
|
|
stbi__skip(s, c.length);
|
|
break;
|
|
case STBI__PNG_TYPE('I','H','D','R'): {
|
|
int comp,filter;
|
|
if (!first) return stbi__err("multiple IHDR","Corrupt PNG");
|
|
first = 0;
|
|
if (c.length != 13) return stbi__err("bad IHDR len","Corrupt PNG");
|
|
s->img_x = stbi__get32be(s); if (s->img_x > (1 << 24)) return stbi__err("too large","Very large image (corrupt?)");
|
|
s->img_y = stbi__get32be(s); if (s->img_y > (1 << 24)) return stbi__err("too large","Very large image (corrupt?)");
|
|
z->depth = stbi__get8(s); if (z->depth != 1 && z->depth != 2 && z->depth != 4 && z->depth != 8 && z->depth != 16) return stbi__err("1/2/4/8/16-bit only","PNG not supported: 1/2/4/8/16-bit only");
|
|
color = stbi__get8(s); if (color > 6) return stbi__err("bad ctype","Corrupt PNG");
|
|
if (color == 3 && z->depth == 16) return stbi__err("bad ctype","Corrupt PNG");
|
|
if (color == 3) pal_img_n = 3; else if (color & 1) return stbi__err("bad ctype","Corrupt PNG");
|
|
comp = stbi__get8(s); if (comp) return stbi__err("bad comp method","Corrupt PNG");
|
|
filter= stbi__get8(s); if (filter) return stbi__err("bad filter method","Corrupt PNG");
|
|
interlace = stbi__get8(s); if (interlace>1) return stbi__err("bad interlace method","Corrupt PNG");
|
|
if (!s->img_x || !s->img_y) return stbi__err("0-pixel image","Corrupt PNG");
|
|
if (!pal_img_n) {
|
|
s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0);
|
|
if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode");
|
|
if (scan == STBI__SCAN_header) return 1;
|
|
} else {
|
|
// if paletted, then pal_n is our final components, and
|
|
// img_n is # components to decompress/filter.
|
|
s->img_n = 1;
|
|
if ((1 << 30) / s->img_x / 4 < s->img_y) return stbi__err("too large","Corrupt PNG");
|
|
// if SCAN_header, have to scan to see if we have a tRNS
|
|
}
|
|
break;
|
|
}
|
|
|
|
case STBI__PNG_TYPE('P','L','T','E'): {
|
|
if (first) return stbi__err("first not IHDR", "Corrupt PNG");
|
|
if (c.length > 256*3) return stbi__err("invalid PLTE","Corrupt PNG");
|
|
pal_len = c.length / 3;
|
|
if (pal_len * 3 != c.length) return stbi__err("invalid PLTE","Corrupt PNG");
|
|
for (i=0; i < pal_len; ++i) {
|
|
palette[i*4+0] = stbi__get8(s);
|
|
palette[i*4+1] = stbi__get8(s);
|
|
palette[i*4+2] = stbi__get8(s);
|
|
palette[i*4+3] = 255;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case STBI__PNG_TYPE('t','R','N','S'): {
|
|
if (first) return stbi__err("first not IHDR", "Corrupt PNG");
|
|
if (z->idata) return stbi__err("tRNS after IDAT","Corrupt PNG");
|
|
if (pal_img_n) {
|
|
if (scan == STBI__SCAN_header) { s->img_n = 4; return 1; }
|
|
if (pal_len == 0) return stbi__err("tRNS before PLTE","Corrupt PNG");
|
|
if (c.length > pal_len) return stbi__err("bad tRNS len","Corrupt PNG");
|
|
pal_img_n = 4;
|
|
for (i=0; i < c.length; ++i)
|
|
palette[i*4+3] = stbi__get8(s);
|
|
} else {
|
|
if (!(s->img_n & 1)) return stbi__err("tRNS with alpha","Corrupt PNG");
|
|
if (c.length != (stbi__uint32) s->img_n*2) return stbi__err("bad tRNS len","Corrupt PNG");
|
|
has_trans = 1;
|
|
if (z->depth == 16) {
|
|
for (k = 0; k < s->img_n; ++k) tc16[k] = stbi__get16be(s); // copy the values as-is
|
|
} else {
|
|
for (k = 0; k < s->img_n; ++k) tc[k] = (stbi_uc)(stbi__get16be(s) & 255) * stbi__depth_scale_table[z->depth]; // non 8-bit images will be larger
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
case STBI__PNG_TYPE('I','D','A','T'): {
|
|
if (first) return stbi__err("first not IHDR", "Corrupt PNG");
|
|
if (pal_img_n && !pal_len) return stbi__err("no PLTE","Corrupt PNG");
|
|
if (scan == STBI__SCAN_header) { s->img_n = pal_img_n; return 1; }
|
|
if ((int)(ioff + c.length) < (int)ioff) return 0;
|
|
if (ioff + c.length > idata_limit) {
|
|
stbi__uint32 idata_limit_old = idata_limit;
|
|
stbi_uc *p;
|
|
if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096;
|
|
while (ioff + c.length > idata_limit)
|
|
idata_limit *= 2;
|
|
STBI_NOTUSED(idata_limit_old);
|
|
p = (stbi_uc *) STBI_REALLOC_SIZED(z->idata, idata_limit_old, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory");
|
|
z->idata = p;
|
|
}
|
|
if (!stbi__getn(s, z->idata+ioff,c.length)) return stbi__err("outofdata","Corrupt PNG");
|
|
ioff += c.length;
|
|
break;
|
|
}
|
|
|
|
case STBI__PNG_TYPE('I','E','N','D'): {
|
|
stbi__uint32 raw_len, bpl;
|
|
if (first) return stbi__err("first not IHDR", "Corrupt PNG");
|
|
if (scan != STBI__SCAN_load) return 1;
|
|
if (z->idata == NULL) return stbi__err("no IDAT","Corrupt PNG");
|
|
// initial guess for decoded data size to avoid unnecessary reallocs
|
|
bpl = (s->img_x * z->depth + 7) / 8; // bytes per line, per component
|
|
raw_len = bpl * s->img_y * s->img_n /* pixels */ + s->img_y /* filter mode per row */;
|
|
z->expanded = (stbi_uc *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, raw_len, (int *) &raw_len, !is_iphone);
|
|
if (z->expanded == NULL) return 0; // zlib should set error
|
|
STBI_FREE(z->idata); z->idata = NULL;
|
|
if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans)
|
|
s->img_out_n = s->img_n+1;
|
|
else
|
|
s->img_out_n = s->img_n;
|
|
if (!stbi__create_png_image(z, z->expanded, raw_len, s->img_out_n, z->depth, color, interlace)) return 0;
|
|
if (has_trans) {
|
|
if (z->depth == 16) {
|
|
if (!stbi__compute_transparency16(z, tc16, s->img_out_n)) return 0;
|
|
} else {
|
|
if (!stbi__compute_transparency(z, tc, s->img_out_n)) return 0;
|
|
}
|
|
}
|
|
if (is_iphone && stbi__de_iphone_flag && s->img_out_n > 2)
|
|
stbi__de_iphone(z);
|
|
if (pal_img_n) {
|
|
// pal_img_n == 3 or 4
|
|
s->img_n = pal_img_n; // record the actual colors we had
|
|
s->img_out_n = pal_img_n;
|
|
if (req_comp >= 3) s->img_out_n = req_comp;
|
|
if (!stbi__expand_png_palette(z, palette, pal_len, s->img_out_n))
|
|
return 0;
|
|
}
|
|
STBI_FREE(z->expanded); z->expanded = NULL;
|
|
return 1;
|
|
}
|
|
|
|
default:
|
|
// if critical, fail
|
|
if (first) return stbi__err("first not IHDR", "Corrupt PNG");
|
|
if ((c.type & (1 << 29)) == 0) {
|
|
#ifndef STBI_NO_FAILURE_STRINGS
|
|
// not threadsafe
|
|
static char invalid_chunk[] = "XXXX PNG chunk not known";
|
|
invalid_chunk[0] = STBI__BYTECAST(c.type >> 24);
|
|
invalid_chunk[1] = STBI__BYTECAST(c.type >> 16);
|
|
invalid_chunk[2] = STBI__BYTECAST(c.type >> 8);
|
|
invalid_chunk[3] = STBI__BYTECAST(c.type >> 0);
|
|
#endif
|
|
return stbi__err(invalid_chunk, "PNG not supported: unknown PNG chunk type");
|
|
}
|
|
stbi__skip(s, c.length);
|
|
break;
|
|
}
|
|
// end of PNG chunk, read and skip CRC
|
|
stbi__get32be(s);
|
|
}
|
|
}
|
|
|
|
static unsigned char *stbi__do_png(stbi__png *p, int *x, int *y, int *n, int req_comp)
|
|
{
|
|
unsigned char *result=NULL;
|
|
if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
|
|
if (stbi__parse_png_file(p, STBI__SCAN_load, req_comp)) {
|
|
if (p->depth == 16) {
|
|
if (!stbi__reduce_png(p)) {
|
|
return result;
|
|
}
|
|
}
|
|
result = p->out;
|
|
p->out = NULL;
|
|
if (req_comp && req_comp != p->s->img_out_n) {
|
|
result = stbi__convert_format(result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y);
|
|
p->s->img_out_n = req_comp;
|
|
if (result == NULL) return result;
|
|
}
|
|
*x = p->s->img_x;
|
|
*y = p->s->img_y;
|
|
if (n) *n = p->s->img_n;
|
|
}
|
|
STBI_FREE(p->out); p->out = NULL;
|
|
STBI_FREE(p->expanded); p->expanded = NULL;
|
|
STBI_FREE(p->idata); p->idata = NULL;
|
|
|
|
return result;
|
|
}
|
|
|
|
static unsigned char *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi__png p;
|
|
p.s = s;
|
|
return stbi__do_png(&p, x,y,comp,req_comp);
|
|
}
|
|
|
|
static int stbi__png_test(stbi__context *s)
|
|
{
|
|
int r;
|
|
r = stbi__check_png_header(s);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
|
|
static int stbi__png_info_raw(stbi__png *p, int *x, int *y, int *comp)
|
|
{
|
|
if (!stbi__parse_png_file(p, STBI__SCAN_header, 0)) {
|
|
stbi__rewind( p->s );
|
|
return 0;
|
|
}
|
|
if (x) *x = p->s->img_x;
|
|
if (y) *y = p->s->img_y;
|
|
if (comp) *comp = p->s->img_n;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
stbi__png p;
|
|
p.s = s;
|
|
return stbi__png_info_raw(&p, x, y, comp);
|
|
}
|
|
#endif
|
|
|
|
// Microsoft/Windows BMP image
|
|
|
|
#ifndef STBI_NO_BMP
|
|
static int stbi__bmp_test_raw(stbi__context *s)
|
|
{
|
|
int r;
|
|
int sz;
|
|
if (stbi__get8(s) != 'B') return 0;
|
|
if (stbi__get8(s) != 'M') return 0;
|
|
stbi__get32le(s); // discard filesize
|
|
stbi__get16le(s); // discard reserved
|
|
stbi__get16le(s); // discard reserved
|
|
stbi__get32le(s); // discard data offset
|
|
sz = stbi__get32le(s);
|
|
r = (sz == 12 || sz == 40 || sz == 56 || sz == 108 || sz == 124);
|
|
return r;
|
|
}
|
|
|
|
static int stbi__bmp_test(stbi__context *s)
|
|
{
|
|
int r = stbi__bmp_test_raw(s);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
|
|
|
|
// returns 0..31 for the highest set bit
|
|
static int stbi__high_bit(unsigned int z)
|
|
{
|
|
int n=0;
|
|
if (z == 0) return -1;
|
|
if (z >= 0x10000) n += 16, z >>= 16;
|
|
if (z >= 0x00100) n += 8, z >>= 8;
|
|
if (z >= 0x00010) n += 4, z >>= 4;
|
|
if (z >= 0x00004) n += 2, z >>= 2;
|
|
if (z >= 0x00002) n += 1, z >>= 1;
|
|
return n;
|
|
}
|
|
|
|
static int stbi__bitcount(unsigned int a)
|
|
{
|
|
a = (a & 0x55555555) + ((a >> 1) & 0x55555555); // max 2
|
|
a = (a & 0x33333333) + ((a >> 2) & 0x33333333); // max 4
|
|
a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits
|
|
a = (a + (a >> 8)); // max 16 per 8 bits
|
|
a = (a + (a >> 16)); // max 32 per 8 bits
|
|
return a & 0xff;
|
|
}
|
|
|
|
static int stbi__shiftsigned(int v, int shift, int bits)
|
|
{
|
|
int result;
|
|
int z=0;
|
|
|
|
if (shift < 0) v <<= -shift;
|
|
else v >>= shift;
|
|
result = v;
|
|
|
|
z = bits;
|
|
while (z < 8) {
|
|
result += v >> z;
|
|
z += bits;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
int bpp, offset, hsz;
|
|
unsigned int mr,mg,mb,ma, all_a;
|
|
} stbi__bmp_data;
|
|
|
|
static void *stbi__bmp_parse_header(stbi__context *s, stbi__bmp_data *info)
|
|
{
|
|
int hsz;
|
|
if (stbi__get8(s) != 'B' || stbi__get8(s) != 'M') return stbi__errpuc("not BMP", "Corrupt BMP");
|
|
stbi__get32le(s); // discard filesize
|
|
stbi__get16le(s); // discard reserved
|
|
stbi__get16le(s); // discard reserved
|
|
info->offset = stbi__get32le(s);
|
|
info->hsz = hsz = stbi__get32le(s);
|
|
info->mr = info->mg = info->mb = info->ma = 0;
|
|
|
|
if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108 && hsz != 124) return stbi__errpuc("unknown BMP", "BMP type not supported: unknown");
|
|
if (hsz == 12) {
|
|
s->img_x = stbi__get16le(s);
|
|
s->img_y = stbi__get16le(s);
|
|
} else {
|
|
s->img_x = stbi__get32le(s);
|
|
s->img_y = stbi__get32le(s);
|
|
}
|
|
if (stbi__get16le(s) != 1) return stbi__errpuc("bad BMP", "bad BMP");
|
|
info->bpp = stbi__get16le(s);
|
|
if (info->bpp == 1) return stbi__errpuc("monochrome", "BMP type not supported: 1-bit");
|
|
if (hsz != 12) {
|
|
int compress = stbi__get32le(s);
|
|
if (compress == 1 || compress == 2) return stbi__errpuc("BMP RLE", "BMP type not supported: RLE");
|
|
stbi__get32le(s); // discard sizeof
|
|
stbi__get32le(s); // discard hres
|
|
stbi__get32le(s); // discard vres
|
|
stbi__get32le(s); // discard colorsused
|
|
stbi__get32le(s); // discard max important
|
|
if (hsz == 40 || hsz == 56) {
|
|
if (hsz == 56) {
|
|
stbi__get32le(s);
|
|
stbi__get32le(s);
|
|
stbi__get32le(s);
|
|
stbi__get32le(s);
|
|
}
|
|
if (info->bpp == 16 || info->bpp == 32) {
|
|
if (compress == 0) {
|
|
if (info->bpp == 32) {
|
|
info->mr = 0xffu << 16;
|
|
info->mg = 0xffu << 8;
|
|
info->mb = 0xffu << 0;
|
|
info->ma = 0xffu << 24;
|
|
info->all_a = 0; // if all_a is 0 at end, then we loaded alpha channel but it was all 0
|
|
} else {
|
|
info->mr = 31u << 10;
|
|
info->mg = 31u << 5;
|
|
info->mb = 31u << 0;
|
|
}
|
|
} else if (compress == 3) {
|
|
info->mr = stbi__get32le(s);
|
|
info->mg = stbi__get32le(s);
|
|
info->mb = stbi__get32le(s);
|
|
// not documented, but generated by photoshop and handled by mspaint
|
|
if (info->mr == info->mg && info->mg == info->mb) {
|
|
// ?!?!?
|
|
return stbi__errpuc("bad BMP", "bad BMP");
|
|
}
|
|
} else
|
|
return stbi__errpuc("bad BMP", "bad BMP");
|
|
}
|
|
} else {
|
|
int i;
|
|
if (hsz != 108 && hsz != 124)
|
|
return stbi__errpuc("bad BMP", "bad BMP");
|
|
info->mr = stbi__get32le(s);
|
|
info->mg = stbi__get32le(s);
|
|
info->mb = stbi__get32le(s);
|
|
info->ma = stbi__get32le(s);
|
|
stbi__get32le(s); // discard color space
|
|
for (i=0; i < 12; ++i)
|
|
stbi__get32le(s); // discard color space parameters
|
|
if (hsz == 124) {
|
|
stbi__get32le(s); // discard rendering intent
|
|
stbi__get32le(s); // discard offset of profile data
|
|
stbi__get32le(s); // discard size of profile data
|
|
stbi__get32le(s); // discard reserved
|
|
}
|
|
}
|
|
}
|
|
return (void *) 1;
|
|
}
|
|
|
|
|
|
static stbi_uc *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *out;
|
|
unsigned int mr=0,mg=0,mb=0,ma=0, all_a;
|
|
stbi_uc pal[256][4];
|
|
int psize=0,i,j,width;
|
|
int flip_vertically, pad, target;
|
|
stbi__bmp_data info;
|
|
|
|
info.all_a = 255;
|
|
if (stbi__bmp_parse_header(s, &info) == NULL)
|
|
return NULL; // error code already set
|
|
|
|
flip_vertically = ((int) s->img_y) > 0;
|
|
s->img_y = abs((int) s->img_y);
|
|
|
|
mr = info.mr;
|
|
mg = info.mg;
|
|
mb = info.mb;
|
|
ma = info.ma;
|
|
all_a = info.all_a;
|
|
|
|
if (info.hsz == 12) {
|
|
if (info.bpp < 24)
|
|
psize = (info.offset - 14 - 24) / 3;
|
|
} else {
|
|
if (info.bpp < 16)
|
|
psize = (info.offset - 14 - info.hsz) >> 2;
|
|
}
|
|
|
|
s->img_n = ma ? 4 : 3;
|
|
if (req_comp && req_comp >= 3) // we can directly decode 3 or 4
|
|
target = req_comp;
|
|
else
|
|
target = s->img_n; // if they want monochrome, we'll post-convert
|
|
|
|
out = (stbi_uc *) stbi__malloc(target * s->img_x * s->img_y);
|
|
if (!out) return stbi__errpuc("outofmem", "Out of memory");
|
|
if (info.bpp < 16) {
|
|
int z=0;
|
|
if (psize == 0 || psize > 256) { STBI_FREE(out); return stbi__errpuc("invalid", "Corrupt BMP"); }
|
|
for (i=0; i < psize; ++i) {
|
|
pal[i][2] = stbi__get8(s);
|
|
pal[i][1] = stbi__get8(s);
|
|
pal[i][0] = stbi__get8(s);
|
|
if (info.hsz != 12) stbi__get8(s);
|
|
pal[i][3] = 255;
|
|
}
|
|
stbi__skip(s, info.offset - 14 - info.hsz - psize * (info.hsz == 12 ? 3 : 4));
|
|
if (info.bpp == 4) width = (s->img_x + 1) >> 1;
|
|
else if (info.bpp == 8) width = s->img_x;
|
|
else { STBI_FREE(out); return stbi__errpuc("bad bpp", "Corrupt BMP"); }
|
|
pad = (-width)&3;
|
|
for (j=0; j < (int) s->img_y; ++j) {
|
|
for (i=0; i < (int) s->img_x; i += 2) {
|
|
int v=stbi__get8(s),v2=0;
|
|
if (info.bpp == 4) {
|
|
v2 = v & 15;
|
|
v >>= 4;
|
|
}
|
|
out[z++] = pal[v][0];
|
|
out[z++] = pal[v][1];
|
|
out[z++] = pal[v][2];
|
|
if (target == 4) out[z++] = 255;
|
|
if (i+1 == (int) s->img_x) break;
|
|
v = (info.bpp == 8) ? stbi__get8(s) : v2;
|
|
out[z++] = pal[v][0];
|
|
out[z++] = pal[v][1];
|
|
out[z++] = pal[v][2];
|
|
if (target == 4) out[z++] = 255;
|
|
}
|
|
stbi__skip(s, pad);
|
|
}
|
|
} else {
|
|
int rshift=0,gshift=0,bshift=0,ashift=0,rcount=0,gcount=0,bcount=0,acount=0;
|
|
int z = 0;
|
|
int easy=0;
|
|
stbi__skip(s, info.offset - 14 - info.hsz);
|
|
if (info.bpp == 24) width = 3 * s->img_x;
|
|
else if (info.bpp == 16) width = 2*s->img_x;
|
|
else /* bpp = 32 and pad = 0 */ width=0;
|
|
pad = (-width) & 3;
|
|
if (info.bpp == 24) {
|
|
easy = 1;
|
|
} else if (info.bpp == 32) {
|
|
if (mb == 0xff && mg == 0xff00 && mr == 0x00ff0000 && ma == 0xff000000)
|
|
easy = 2;
|
|
}
|
|
if (!easy) {
|
|
if (!mr || !mg || !mb) { STBI_FREE(out); return stbi__errpuc("bad masks", "Corrupt BMP"); }
|
|
// right shift amt to put high bit in position #7
|
|
rshift = stbi__high_bit(mr)-7; rcount = stbi__bitcount(mr);
|
|
gshift = stbi__high_bit(mg)-7; gcount = stbi__bitcount(mg);
|
|
bshift = stbi__high_bit(mb)-7; bcount = stbi__bitcount(mb);
|
|
ashift = stbi__high_bit(ma)-7; acount = stbi__bitcount(ma);
|
|
}
|
|
for (j=0; j < (int) s->img_y; ++j) {
|
|
if (easy) {
|
|
for (i=0; i < (int) s->img_x; ++i) {
|
|
unsigned char a;
|
|
out[z+2] = stbi__get8(s);
|
|
out[z+1] = stbi__get8(s);
|
|
out[z+0] = stbi__get8(s);
|
|
z += 3;
|
|
a = (easy == 2 ? stbi__get8(s) : 255);
|
|
all_a |= a;
|
|
if (target == 4) out[z++] = a;
|
|
}
|
|
} else {
|
|
int bpp = info.bpp;
|
|
for (i=0; i < (int) s->img_x; ++i) {
|
|
stbi__uint32 v = (bpp == 16 ? (stbi__uint32) stbi__get16le(s) : stbi__get32le(s));
|
|
int a;
|
|
out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mr, rshift, rcount));
|
|
out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mg, gshift, gcount));
|
|
out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mb, bshift, bcount));
|
|
a = (ma ? stbi__shiftsigned(v & ma, ashift, acount) : 255);
|
|
all_a |= a;
|
|
if (target == 4) out[z++] = STBI__BYTECAST(a);
|
|
}
|
|
}
|
|
stbi__skip(s, pad);
|
|
}
|
|
}
|
|
|
|
// if alpha channel is all 0s, replace with all 255s
|
|
if (target == 4 && all_a == 0)
|
|
for (i=4*s->img_x*s->img_y-1; i >= 0; i -= 4)
|
|
out[i] = 255;
|
|
|
|
if (flip_vertically) {
|
|
stbi_uc t;
|
|
for (j=0; j < (int) s->img_y>>1; ++j) {
|
|
stbi_uc *p1 = out + j *s->img_x*target;
|
|
stbi_uc *p2 = out + (s->img_y-1-j)*s->img_x*target;
|
|
for (i=0; i < (int) s->img_x*target; ++i) {
|
|
t = p1[i], p1[i] = p2[i], p2[i] = t;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (req_comp && req_comp != target) {
|
|
out = stbi__convert_format(out, target, req_comp, s->img_x, s->img_y);
|
|
if (out == NULL) return out; // stbi__convert_format frees input on failure
|
|
}
|
|
|
|
*x = s->img_x;
|
|
*y = s->img_y;
|
|
if (comp) *comp = s->img_n;
|
|
return out;
|
|
}
|
|
#endif
|
|
|
|
// Targa Truevision - TGA
|
|
// by Jonathan Dummer
|
|
#ifndef STBI_NO_TGA
|
|
// returns STBI_rgb or whatever, 0 on error
|
|
static int stbi__tga_get_comp(int bits_per_pixel, int is_grey, int* is_rgb16)
|
|
{
|
|
// only RGB or RGBA (incl. 16bit) or grey allowed
|
|
if(is_rgb16) *is_rgb16 = 0;
|
|
switch(bits_per_pixel) {
|
|
case 8: return STBI_grey;
|
|
case 16: if(is_grey) return STBI_grey_alpha;
|
|
// else: fall-through
|
|
case 15: if(is_rgb16) *is_rgb16 = 1;
|
|
return STBI_rgb;
|
|
case 24: // fall-through
|
|
case 32: return bits_per_pixel/8;
|
|
default: return 0;
|
|
}
|
|
}
|
|
|
|
static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
int tga_w, tga_h, tga_comp, tga_image_type, tga_bits_per_pixel, tga_colormap_bpp;
|
|
int sz, tga_colormap_type;
|
|
stbi__get8(s); // discard Offset
|
|
tga_colormap_type = stbi__get8(s); // colormap type
|
|
if( tga_colormap_type > 1 ) {
|
|
stbi__rewind(s);
|
|
return 0; // only RGB or indexed allowed
|
|
}
|
|
tga_image_type = stbi__get8(s); // image type
|
|
if ( tga_colormap_type == 1 ) { // colormapped (paletted) image
|
|
if (tga_image_type != 1 && tga_image_type != 9) {
|
|
stbi__rewind(s);
|
|
return 0;
|
|
}
|
|
stbi__skip(s,4); // skip index of first colormap entry and number of entries
|
|
sz = stbi__get8(s); // check bits per palette color entry
|
|
if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) {
|
|
stbi__rewind(s);
|
|
return 0;
|
|
}
|
|
stbi__skip(s,4); // skip image x and y origin
|
|
tga_colormap_bpp = sz;
|
|
} else { // "normal" image w/o colormap - only RGB or grey allowed, +/- RLE
|
|
if ( (tga_image_type != 2) && (tga_image_type != 3) && (tga_image_type != 10) && (tga_image_type != 11) ) {
|
|
stbi__rewind(s);
|
|
return 0; // only RGB or grey allowed, +/- RLE
|
|
}
|
|
stbi__skip(s,9); // skip colormap specification and image x/y origin
|
|
tga_colormap_bpp = 0;
|
|
}
|
|
tga_w = stbi__get16le(s);
|
|
if( tga_w < 1 ) {
|
|
stbi__rewind(s);
|
|
return 0; // test width
|
|
}
|
|
tga_h = stbi__get16le(s);
|
|
if( tga_h < 1 ) {
|
|
stbi__rewind(s);
|
|
return 0; // test height
|
|
}
|
|
tga_bits_per_pixel = stbi__get8(s); // bits per pixel
|
|
stbi__get8(s); // ignore alpha bits
|
|
if (tga_colormap_bpp != 0) {
|
|
if((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16)) {
|
|
// when using a colormap, tga_bits_per_pixel is the size of the indexes
|
|
// I don't think anything but 8 or 16bit indexes makes sense
|
|
stbi__rewind(s);
|
|
return 0;
|
|
}
|
|
tga_comp = stbi__tga_get_comp(tga_colormap_bpp, 0, NULL);
|
|
} else {
|
|
tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3) || (tga_image_type == 11), NULL);
|
|
}
|
|
if(!tga_comp) {
|
|
stbi__rewind(s);
|
|
return 0;
|
|
}
|
|
if (x) *x = tga_w;
|
|
if (y) *y = tga_h;
|
|
if (comp) *comp = tga_comp;
|
|
return 1; // seems to have passed everything
|
|
}
|
|
|
|
static int stbi__tga_test(stbi__context *s)
|
|
{
|
|
int res = 0;
|
|
int sz, tga_color_type;
|
|
stbi__get8(s); // discard Offset
|
|
tga_color_type = stbi__get8(s); // color type
|
|
if ( tga_color_type > 1 ) goto errorEnd; // only RGB or indexed allowed
|
|
sz = stbi__get8(s); // image type
|
|
if ( tga_color_type == 1 ) { // colormapped (paletted) image
|
|
if (sz != 1 && sz != 9) goto errorEnd; // colortype 1 demands image type 1 or 9
|
|
stbi__skip(s,4); // skip index of first colormap entry and number of entries
|
|
sz = stbi__get8(s); // check bits per palette color entry
|
|
if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd;
|
|
stbi__skip(s,4); // skip image x and y origin
|
|
} else { // "normal" image w/o colormap
|
|
if ( (sz != 2) && (sz != 3) && (sz != 10) && (sz != 11) ) goto errorEnd; // only RGB or grey allowed, +/- RLE
|
|
stbi__skip(s,9); // skip colormap specification and image x/y origin
|
|
}
|
|
if ( stbi__get16le(s) < 1 ) goto errorEnd; // test width
|
|
if ( stbi__get16le(s) < 1 ) goto errorEnd; // test height
|
|
sz = stbi__get8(s); // bits per pixel
|
|
if ( (tga_color_type == 1) && (sz != 8) && (sz != 16) ) goto errorEnd; // for colormapped images, bpp is size of an index
|
|
if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd;
|
|
|
|
res = 1; // if we got this far, everything's good and we can return 1 instead of 0
|
|
|
|
errorEnd:
|
|
stbi__rewind(s);
|
|
return res;
|
|
}
|
|
|
|
// read 16bit value and convert to 24bit RGB
|
|
void stbi__tga_read_rgb16(stbi__context *s, stbi_uc* out)
|
|
{
|
|
stbi__uint16 px = stbi__get16le(s);
|
|
stbi__uint16 fiveBitMask = 31;
|
|
// we have 3 channels with 5bits each
|
|
int r = (px >> 10) & fiveBitMask;
|
|
int g = (px >> 5) & fiveBitMask;
|
|
int b = px & fiveBitMask;
|
|
// Note that this saves the data in RGB(A) order, so it doesn't need to be swapped later
|
|
out[0] = (r * 255)/31;
|
|
out[1] = (g * 255)/31;
|
|
out[2] = (b * 255)/31;
|
|
|
|
// some people claim that the most significant bit might be used for alpha
|
|
// (possibly if an alpha-bit is set in the "image descriptor byte")
|
|
// but that only made 16bit test images completely translucent..
|
|
// so let's treat all 15 and 16bit TGAs as RGB with no alpha.
|
|
}
|
|
|
|
static stbi_uc *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
// read in the TGA header stuff
|
|
int tga_offset = stbi__get8(s);
|
|
int tga_indexed = stbi__get8(s);
|
|
int tga_image_type = stbi__get8(s);
|
|
int tga_is_RLE = 0;
|
|
int tga_palette_start = stbi__get16le(s);
|
|
int tga_palette_len = stbi__get16le(s);
|
|
int tga_palette_bits = stbi__get8(s);
|
|
int tga_x_origin = stbi__get16le(s);
|
|
int tga_y_origin = stbi__get16le(s);
|
|
int tga_width = stbi__get16le(s);
|
|
int tga_height = stbi__get16le(s);
|
|
int tga_bits_per_pixel = stbi__get8(s);
|
|
int tga_comp, tga_rgb16=0;
|
|
int tga_inverted = stbi__get8(s);
|
|
// int tga_alpha_bits = tga_inverted & 15; // the 4 lowest bits - unused (useless?)
|
|
// image data
|
|
unsigned char *tga_data;
|
|
unsigned char *tga_palette = NULL;
|
|
int i, j;
|
|
unsigned char raw_data[4];
|
|
int RLE_count = 0;
|
|
int RLE_repeating = 0;
|
|
int read_next_pixel = 1;
|
|
|
|
// do a tiny bit of precessing
|
|
if ( tga_image_type >= 8 )
|
|
{
|
|
tga_image_type -= 8;
|
|
tga_is_RLE = 1;
|
|
}
|
|
tga_inverted = 1 - ((tga_inverted >> 5) & 1);
|
|
|
|
// If I'm paletted, then I'll use the number of bits from the palette
|
|
if ( tga_indexed ) tga_comp = stbi__tga_get_comp(tga_palette_bits, 0, &tga_rgb16);
|
|
else tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3), &tga_rgb16);
|
|
|
|
if(!tga_comp) // shouldn't really happen, stbi__tga_test() should have ensured basic consistency
|
|
return stbi__errpuc("bad format", "Can't find out TGA pixelformat");
|
|
|
|
// tga info
|
|
*x = tga_width;
|
|
*y = tga_height;
|
|
if (comp) *comp = tga_comp;
|
|
|
|
tga_data = (unsigned char*)stbi__malloc( (size_t)tga_width * tga_height * tga_comp );
|
|
if (!tga_data) return stbi__errpuc("outofmem", "Out of memory");
|
|
|
|
// skip to the data's starting position (offset usually = 0)
|
|
stbi__skip(s, tga_offset );
|
|
|
|
if ( !tga_indexed && !tga_is_RLE && !tga_rgb16 ) {
|
|
for (i=0; i < tga_height; ++i) {
|
|
int row = tga_inverted ? tga_height -i - 1 : i;
|
|
stbi_uc *tga_row = tga_data + row*tga_width*tga_comp;
|
|
stbi__getn(s, tga_row, tga_width * tga_comp);
|
|
}
|
|
} else {
|
|
// do I need to load a palette?
|
|
if ( tga_indexed)
|
|
{
|
|
// any data to skip? (offset usually = 0)
|
|
stbi__skip(s, tga_palette_start );
|
|
// load the palette
|
|
tga_palette = (unsigned char*)stbi__malloc( tga_palette_len * tga_comp );
|
|
if (!tga_palette) {
|
|
STBI_FREE(tga_data);
|
|
return stbi__errpuc("outofmem", "Out of memory");
|
|
}
|
|
if (tga_rgb16) {
|
|
stbi_uc *pal_entry = tga_palette;
|
|
STBI_ASSERT(tga_comp == STBI_rgb);
|
|
for (i=0; i < tga_palette_len; ++i) {
|
|
stbi__tga_read_rgb16(s, pal_entry);
|
|
pal_entry += tga_comp;
|
|
}
|
|
} else if (!stbi__getn(s, tga_palette, tga_palette_len * tga_comp)) {
|
|
STBI_FREE(tga_data);
|
|
STBI_FREE(tga_palette);
|
|
return stbi__errpuc("bad palette", "Corrupt TGA");
|
|
}
|
|
}
|
|
// load the data
|
|
for (i=0; i < tga_width * tga_height; ++i)
|
|
{
|
|
// if I'm in RLE mode, do I need to get a RLE stbi__pngchunk?
|
|
if ( tga_is_RLE )
|
|
{
|
|
if ( RLE_count == 0 )
|
|
{
|
|
// yep, get the next byte as a RLE command
|
|
int RLE_cmd = stbi__get8(s);
|
|
RLE_count = 1 + (RLE_cmd & 127);
|
|
RLE_repeating = RLE_cmd >> 7;
|
|
read_next_pixel = 1;
|
|
} else if ( !RLE_repeating )
|
|
{
|
|
read_next_pixel = 1;
|
|
}
|
|
} else
|
|
{
|
|
read_next_pixel = 1;
|
|
}
|
|
// OK, if I need to read a pixel, do it now
|
|
if ( read_next_pixel )
|
|
{
|
|
// load however much data we did have
|
|
if ( tga_indexed )
|
|
{
|
|
// read in index, then perform the lookup
|
|
int pal_idx = (tga_bits_per_pixel == 8) ? stbi__get8(s) : stbi__get16le(s);
|
|
if ( pal_idx >= tga_palette_len ) {
|
|
// invalid index
|
|
pal_idx = 0;
|
|
}
|
|
pal_idx *= tga_comp;
|
|
for (j = 0; j < tga_comp; ++j) {
|
|
raw_data[j] = tga_palette[pal_idx+j];
|
|
}
|
|
} else if(tga_rgb16) {
|
|
STBI_ASSERT(tga_comp == STBI_rgb);
|
|
stbi__tga_read_rgb16(s, raw_data);
|
|
} else {
|
|
// read in the data raw
|
|
for (j = 0; j < tga_comp; ++j) {
|
|
raw_data[j] = stbi__get8(s);
|
|
}
|
|
}
|
|
// clear the reading flag for the next pixel
|
|
read_next_pixel = 0;
|
|
} // end of reading a pixel
|
|
|
|
// copy data
|
|
for (j = 0; j < tga_comp; ++j)
|
|
tga_data[i*tga_comp+j] = raw_data[j];
|
|
|
|
// in case we're in RLE mode, keep counting down
|
|
--RLE_count;
|
|
}
|
|
// do I need to invert the image?
|
|
if ( tga_inverted )
|
|
{
|
|
for (j = 0; j*2 < tga_height; ++j)
|
|
{
|
|
int index1 = j * tga_width * tga_comp;
|
|
int index2 = (tga_height - 1 - j) * tga_width * tga_comp;
|
|
for (i = tga_width * tga_comp; i > 0; --i)
|
|
{
|
|
unsigned char temp = tga_data[index1];
|
|
tga_data[index1] = tga_data[index2];
|
|
tga_data[index2] = temp;
|
|
++index1;
|
|
++index2;
|
|
}
|
|
}
|
|
}
|
|
// clear my palette, if I had one
|
|
if ( tga_palette != NULL )
|
|
{
|
|
STBI_FREE( tga_palette );
|
|
}
|
|
}
|
|
|
|
// swap RGB - if the source data was RGB16, it already is in the right order
|
|
if (tga_comp >= 3 && !tga_rgb16)
|
|
{
|
|
unsigned char* tga_pixel = tga_data;
|
|
for (i=0; i < tga_width * tga_height; ++i)
|
|
{
|
|
unsigned char temp = tga_pixel[0];
|
|
tga_pixel[0] = tga_pixel[2];
|
|
tga_pixel[2] = temp;
|
|
tga_pixel += tga_comp;
|
|
}
|
|
}
|
|
|
|
// convert to target component count
|
|
if (req_comp && req_comp != tga_comp)
|
|
tga_data = stbi__convert_format(tga_data, tga_comp, req_comp, tga_width, tga_height);
|
|
|
|
// the things I do to get rid of an error message, and yet keep
|
|
// Microsoft's C compilers happy... [8^(
|
|
tga_palette_start = tga_palette_len = tga_palette_bits =
|
|
tga_x_origin = tga_y_origin = 0;
|
|
// OK, done
|
|
return tga_data;
|
|
}
|
|
#endif
|
|
|
|
// *************************************************************************************************
|
|
// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB
|
|
|
|
#ifndef STBI_NO_PSD
|
|
static int stbi__psd_test(stbi__context *s)
|
|
{
|
|
int r = (stbi__get32be(s) == 0x38425053);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
|
|
static stbi_uc *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
int pixelCount;
|
|
int channelCount, compression;
|
|
int channel, i, count, len;
|
|
int bitdepth;
|
|
int w,h;
|
|
stbi_uc *out;
|
|
|
|
// Check identifier
|
|
if (stbi__get32be(s) != 0x38425053) // "8BPS"
|
|
return stbi__errpuc("not PSD", "Corrupt PSD image");
|
|
|
|
// Check file type version.
|
|
if (stbi__get16be(s) != 1)
|
|
return stbi__errpuc("wrong version", "Unsupported version of PSD image");
|
|
|
|
// Skip 6 reserved bytes.
|
|
stbi__skip(s, 6 );
|
|
|
|
// Read the number of channels (R, G, B, A, etc).
|
|
channelCount = stbi__get16be(s);
|
|
if (channelCount < 0 || channelCount > 16)
|
|
return stbi__errpuc("wrong channel count", "Unsupported number of channels in PSD image");
|
|
|
|
// Read the rows and columns of the image.
|
|
h = stbi__get32be(s);
|
|
w = stbi__get32be(s);
|
|
|
|
// Make sure the depth is 8 bits.
|
|
bitdepth = stbi__get16be(s);
|
|
if (bitdepth != 8 && bitdepth != 16)
|
|
return stbi__errpuc("unsupported bit depth", "PSD bit depth is not 8 or 16 bit");
|
|
|
|
// Make sure the color mode is RGB.
|
|
// Valid options are:
|
|
// 0: Bitmap
|
|
// 1: Grayscale
|
|
// 2: Indexed color
|
|
// 3: RGB color
|
|
// 4: CMYK color
|
|
// 7: Multichannel
|
|
// 8: Duotone
|
|
// 9: Lab color
|
|
if (stbi__get16be(s) != 3)
|
|
return stbi__errpuc("wrong color format", "PSD is not in RGB color format");
|
|
|
|
// Skip the Mode Data. (It's the palette for indexed color; other info for other modes.)
|
|
stbi__skip(s,stbi__get32be(s) );
|
|
|
|
// Skip the image resources. (resolution, pen tool paths, etc)
|
|
stbi__skip(s, stbi__get32be(s) );
|
|
|
|
// Skip the reserved data.
|
|
stbi__skip(s, stbi__get32be(s) );
|
|
|
|
// Find out if the data is compressed.
|
|
// Known values:
|
|
// 0: no compression
|
|
// 1: RLE compressed
|
|
compression = stbi__get16be(s);
|
|
if (compression > 1)
|
|
return stbi__errpuc("bad compression", "PSD has an unknown compression format");
|
|
|
|
// Create the destination image.
|
|
out = (stbi_uc *) stbi__malloc(4 * w*h);
|
|
if (!out) return stbi__errpuc("outofmem", "Out of memory");
|
|
pixelCount = w*h;
|
|
|
|
// Initialize the data to zero.
|
|
//memset( out, 0, pixelCount * 4 );
|
|
|
|
// Finally, the image data.
|
|
if (compression) {
|
|
// RLE as used by .PSD and .TIFF
|
|
// Loop until you get the number of unpacked bytes you are expecting:
|
|
// Read the next source byte into n.
|
|
// If n is between 0 and 127 inclusive, copy the next n+1 bytes literally.
|
|
// Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times.
|
|
// Else if n is 128, noop.
|
|
// Endloop
|
|
|
|
// The RLE-compressed data is preceeded by a 2-byte data count for each row in the data,
|
|
// which we're going to just skip.
|
|
stbi__skip(s, h * channelCount * 2 );
|
|
|
|
// Read the RLE data by channel.
|
|
for (channel = 0; channel < 4; channel++) {
|
|
stbi_uc *p;
|
|
|
|
p = out+channel;
|
|
if (channel >= channelCount) {
|
|
// Fill this channel with default data.
|
|
for (i = 0; i < pixelCount; i++, p += 4)
|
|
*p = (channel == 3 ? 255 : 0);
|
|
} else {
|
|
// Read the RLE data.
|
|
count = 0;
|
|
while (count < pixelCount) {
|
|
len = stbi__get8(s);
|
|
if (len == 128) {
|
|
// No-op.
|
|
} else if (len < 128) {
|
|
// Copy next len+1 bytes literally.
|
|
len++;
|
|
count += len;
|
|
while (len) {
|
|
*p = stbi__get8(s);
|
|
p += 4;
|
|
len--;
|
|
}
|
|
} else if (len > 128) {
|
|
stbi_uc val;
|
|
// Next -len+1 bytes in the dest are replicated from next source byte.
|
|
// (Interpret len as a negative 8-bit int.)
|
|
len ^= 0x0FF;
|
|
len += 2;
|
|
val = stbi__get8(s);
|
|
count += len;
|
|
while (len) {
|
|
*p = val;
|
|
p += 4;
|
|
len--;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
} else {
|
|
// We're at the raw image data. It's each channel in order (Red, Green, Blue, Alpha, ...)
|
|
// where each channel consists of an 8-bit value for each pixel in the image.
|
|
|
|
// Read the data by channel.
|
|
for (channel = 0; channel < 4; channel++) {
|
|
stbi_uc *p;
|
|
|
|
p = out + channel;
|
|
if (channel >= channelCount) {
|
|
// Fill this channel with default data.
|
|
stbi_uc val = channel == 3 ? 255 : 0;
|
|
for (i = 0; i < pixelCount; i++, p += 4)
|
|
*p = val;
|
|
} else {
|
|
// Read the data.
|
|
if (bitdepth == 16) {
|
|
for (i = 0; i < pixelCount; i++, p += 4)
|
|
*p = (stbi_uc) (stbi__get16be(s) >> 8);
|
|
} else {
|
|
for (i = 0; i < pixelCount; i++, p += 4)
|
|
*p = stbi__get8(s);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (channelCount >= 4) {
|
|
for (i=0; i < w*h; ++i) {
|
|
unsigned char *pixel = out + 4*i;
|
|
if (pixel[3] != 0 && pixel[3] != 255) {
|
|
// remove weird white matte from PSD
|
|
float a = pixel[3] / 255.0f;
|
|
float ra = 1.0f / a;
|
|
float inv_a = 255.0f * (1 - ra);
|
|
pixel[0] = (unsigned char) (pixel[0]*ra + inv_a);
|
|
pixel[1] = (unsigned char) (pixel[1]*ra + inv_a);
|
|
pixel[2] = (unsigned char) (pixel[2]*ra + inv_a);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (req_comp && req_comp != 4) {
|
|
out = stbi__convert_format(out, 4, req_comp, w, h);
|
|
if (out == NULL) return out; // stbi__convert_format frees input on failure
|
|
}
|
|
|
|
if (comp) *comp = 4;
|
|
*y = h;
|
|
*x = w;
|
|
|
|
return out;
|
|
}
|
|
#endif
|
|
|
|
// *************************************************************************************************
|
|
// Softimage PIC loader
|
|
// by Tom Seddon
|
|
//
|
|
// See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format
|
|
// See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/
|
|
|
|
#ifndef STBI_NO_PIC
|
|
static int stbi__pic_is4(stbi__context *s,const char *str)
|
|
{
|
|
int i;
|
|
for (i=0; i<4; ++i)
|
|
if (stbi__get8(s) != (stbi_uc)str[i])
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__pic_test_core(stbi__context *s)
|
|
{
|
|
int i;
|
|
|
|
if (!stbi__pic_is4(s,"\x53\x80\xF6\x34"))
|
|
return 0;
|
|
|
|
for(i=0;i<84;++i)
|
|
stbi__get8(s);
|
|
|
|
if (!stbi__pic_is4(s,"PICT"))
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
stbi_uc size,type,channel;
|
|
} stbi__pic_packet;
|
|
|
|
static stbi_uc *stbi__readval(stbi__context *s, int channel, stbi_uc *dest)
|
|
{
|
|
int mask=0x80, i;
|
|
|
|
for (i=0; i<4; ++i, mask>>=1) {
|
|
if (channel & mask) {
|
|
if (stbi__at_eof(s)) return stbi__errpuc("bad file","PIC file too short");
|
|
dest[i]=stbi__get8(s);
|
|
}
|
|
}
|
|
|
|
return dest;
|
|
}
|
|
|
|
static void stbi__copyval(int channel,stbi_uc *dest,const stbi_uc *src)
|
|
{
|
|
int mask=0x80,i;
|
|
|
|
for (i=0;i<4; ++i, mask>>=1)
|
|
if (channel&mask)
|
|
dest[i]=src[i];
|
|
}
|
|
|
|
static stbi_uc *stbi__pic_load_core(stbi__context *s,int width,int height,int *comp, stbi_uc *result)
|
|
{
|
|
int act_comp=0,num_packets=0,y,chained;
|
|
stbi__pic_packet packets[10];
|
|
|
|
// this will (should...) cater for even some bizarre stuff like having data
|
|
// for the same channel in multiple packets.
|
|
do {
|
|
stbi__pic_packet *packet;
|
|
|
|
if (num_packets==sizeof(packets)/sizeof(packets[0]))
|
|
return stbi__errpuc("bad format","too many packets");
|
|
|
|
packet = &packets[num_packets++];
|
|
|
|
chained = stbi__get8(s);
|
|
packet->size = stbi__get8(s);
|
|
packet->type = stbi__get8(s);
|
|
packet->channel = stbi__get8(s);
|
|
|
|
act_comp |= packet->channel;
|
|
|
|
if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (reading packets)");
|
|
if (packet->size != 8) return stbi__errpuc("bad format","packet isn't 8bpp");
|
|
} while (chained);
|
|
|
|
*comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel?
|
|
|
|
for(y=0; y<height; ++y) {
|
|
int packet_idx;
|
|
|
|
for(packet_idx=0; packet_idx < num_packets; ++packet_idx) {
|
|
stbi__pic_packet *packet = &packets[packet_idx];
|
|
stbi_uc *dest = result+y*width*4;
|
|
|
|
switch (packet->type) {
|
|
default:
|
|
return stbi__errpuc("bad format","packet has bad compression type");
|
|
|
|
case 0: {//uncompressed
|
|
int x;
|
|
|
|
for(x=0;x<width;++x, dest+=4)
|
|
if (!stbi__readval(s,packet->channel,dest))
|
|
return 0;
|
|
break;
|
|
}
|
|
|
|
case 1://Pure RLE
|
|
{
|
|
int left=width, i;
|
|
|
|
while (left>0) {
|
|
stbi_uc count,value[4];
|
|
|
|
count=stbi__get8(s);
|
|
if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (pure read count)");
|
|
|
|
if (count > left)
|
|
count = (stbi_uc) left;
|
|
|
|
if (!stbi__readval(s,packet->channel,value)) return 0;
|
|
|
|
for(i=0; i<count; ++i,dest+=4)
|
|
stbi__copyval(packet->channel,dest,value);
|
|
left -= count;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case 2: {//Mixed RLE
|
|
int left=width;
|
|
while (left>0) {
|
|
int count = stbi__get8(s), i;
|
|
if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (mixed read count)");
|
|
|
|
if (count >= 128) { // Repeated
|
|
stbi_uc value[4];
|
|
|
|
if (count==128)
|
|
count = stbi__get16be(s);
|
|
else
|
|
count -= 127;
|
|
if (count > left)
|
|
return stbi__errpuc("bad file","scanline overrun");
|
|
|
|
if (!stbi__readval(s,packet->channel,value))
|
|
return 0;
|
|
|
|
for(i=0;i<count;++i, dest += 4)
|
|
stbi__copyval(packet->channel,dest,value);
|
|
} else { // Raw
|
|
++count;
|
|
if (count>left) return stbi__errpuc("bad file","scanline overrun");
|
|
|
|
for(i=0;i<count;++i, dest+=4)
|
|
if (!stbi__readval(s,packet->channel,dest))
|
|
return 0;
|
|
}
|
|
left-=count;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
static stbi_uc *stbi__pic_load(stbi__context *s,int *px,int *py,int *comp,int req_comp)
|
|
{
|
|
stbi_uc *result;
|
|
int i, x,y;
|
|
|
|
for (i=0; i<92; ++i)
|
|
stbi__get8(s);
|
|
|
|
x = stbi__get16be(s);
|
|
y = stbi__get16be(s);
|
|
if (stbi__at_eof(s)) return stbi__errpuc("bad file","file too short (pic header)");
|
|
if ((1 << 28) / x < y) return stbi__errpuc("too large", "Image too large to decode");
|
|
|
|
stbi__get32be(s); //skip `ratio'
|
|
stbi__get16be(s); //skip `fields'
|
|
stbi__get16be(s); //skip `pad'
|
|
|
|
// intermediate buffer is RGBA
|
|
result = (stbi_uc *) stbi__malloc(x*y*4);
|
|
memset(result, 0xff, x*y*4);
|
|
|
|
if (!stbi__pic_load_core(s,x,y,comp, result)) {
|
|
STBI_FREE(result);
|
|
result=0;
|
|
}
|
|
*px = x;
|
|
*py = y;
|
|
if (req_comp == 0) req_comp = *comp;
|
|
result=stbi__convert_format(result,4,req_comp,x,y);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int stbi__pic_test(stbi__context *s)
|
|
{
|
|
int r = stbi__pic_test_core(s);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
// *************************************************************************************************
|
|
// GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb
|
|
|
|
#ifndef STBI_NO_GIF
|
|
typedef struct
|
|
{
|
|
stbi__int16 prefix;
|
|
stbi_uc first;
|
|
stbi_uc suffix;
|
|
} stbi__gif_lzw;
|
|
|
|
typedef struct
|
|
{
|
|
int w,h;
|
|
stbi_uc *out, *old_out; // output buffer (always 4 components)
|
|
int flags, bgindex, ratio, transparent, eflags, delay;
|
|
stbi_uc pal[256][4];
|
|
stbi_uc lpal[256][4];
|
|
stbi__gif_lzw codes[4096];
|
|
stbi_uc *color_table;
|
|
int parse, step;
|
|
int lflags;
|
|
int start_x, start_y;
|
|
int max_x, max_y;
|
|
int cur_x, cur_y;
|
|
int line_size;
|
|
} stbi__gif;
|
|
|
|
static int stbi__gif_test_raw(stbi__context *s)
|
|
{
|
|
int sz;
|
|
if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') return 0;
|
|
sz = stbi__get8(s);
|
|
if (sz != '9' && sz != '7') return 0;
|
|
if (stbi__get8(s) != 'a') return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__gif_test(stbi__context *s)
|
|
{
|
|
int r = stbi__gif_test_raw(s);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
|
|
static void stbi__gif_parse_colortable(stbi__context *s, stbi_uc pal[256][4], int num_entries, int transp)
|
|
{
|
|
int i;
|
|
for (i=0; i < num_entries; ++i) {
|
|
pal[i][2] = stbi__get8(s);
|
|
pal[i][1] = stbi__get8(s);
|
|
pal[i][0] = stbi__get8(s);
|
|
pal[i][3] = transp == i ? 0 : 255;
|
|
}
|
|
}
|
|
|
|
static int stbi__gif_header(stbi__context *s, stbi__gif *g, int *comp, int is_info)
|
|
{
|
|
stbi_uc version;
|
|
if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8')
|
|
return stbi__err("not GIF", "Corrupt GIF");
|
|
|
|
version = stbi__get8(s);
|
|
if (version != '7' && version != '9') return stbi__err("not GIF", "Corrupt GIF");
|
|
if (stbi__get8(s) != 'a') return stbi__err("not GIF", "Corrupt GIF");
|
|
|
|
stbi__g_failure_reason = "";
|
|
g->w = stbi__get16le(s);
|
|
g->h = stbi__get16le(s);
|
|
g->flags = stbi__get8(s);
|
|
g->bgindex = stbi__get8(s);
|
|
g->ratio = stbi__get8(s);
|
|
g->transparent = -1;
|
|
|
|
if (comp != 0) *comp = 4; // can't actually tell whether it's 3 or 4 until we parse the comments
|
|
|
|
if (is_info) return 1;
|
|
|
|
if (g->flags & 0x80)
|
|
stbi__gif_parse_colortable(s,g->pal, 2 << (g->flags & 7), -1);
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__gif_info_raw(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
stbi__gif* g = (stbi__gif*) stbi__malloc(sizeof(stbi__gif));
|
|
if (!stbi__gif_header(s, g, comp, 1)) {
|
|
STBI_FREE(g);
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
if (x) *x = g->w;
|
|
if (y) *y = g->h;
|
|
STBI_FREE(g);
|
|
return 1;
|
|
}
|
|
|
|
static void stbi__out_gif_code(stbi__gif *g, stbi__uint16 code)
|
|
{
|
|
stbi_uc *p, *c;
|
|
|
|
// recurse to decode the prefixes, since the linked-list is backwards,
|
|
// and working backwards through an interleaved image would be nasty
|
|
if (g->codes[code].prefix >= 0)
|
|
stbi__out_gif_code(g, g->codes[code].prefix);
|
|
|
|
if (g->cur_y >= g->max_y) return;
|
|
|
|
p = &g->out[g->cur_x + g->cur_y];
|
|
c = &g->color_table[g->codes[code].suffix * 4];
|
|
|
|
if (c[3] >= 128) {
|
|
p[0] = c[2];
|
|
p[1] = c[1];
|
|
p[2] = c[0];
|
|
p[3] = c[3];
|
|
}
|
|
g->cur_x += 4;
|
|
|
|
if (g->cur_x >= g->max_x) {
|
|
g->cur_x = g->start_x;
|
|
g->cur_y += g->step;
|
|
|
|
while (g->cur_y >= g->max_y && g->parse > 0) {
|
|
g->step = (1 << g->parse) * g->line_size;
|
|
g->cur_y = g->start_y + (g->step >> 1);
|
|
--g->parse;
|
|
}
|
|
}
|
|
}
|
|
|
|
static stbi_uc *stbi__process_gif_raster(stbi__context *s, stbi__gif *g)
|
|
{
|
|
stbi_uc lzw_cs;
|
|
stbi__int32 len, init_code;
|
|
stbi__uint32 first;
|
|
stbi__int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear;
|
|
stbi__gif_lzw *p;
|
|
|
|
lzw_cs = stbi__get8(s);
|
|
if (lzw_cs > 12) return NULL;
|
|
clear = 1 << lzw_cs;
|
|
first = 1;
|
|
codesize = lzw_cs + 1;
|
|
codemask = (1 << codesize) - 1;
|
|
bits = 0;
|
|
valid_bits = 0;
|
|
for (init_code = 0; init_code < clear; init_code++) {
|
|
g->codes[init_code].prefix = -1;
|
|
g->codes[init_code].first = (stbi_uc) init_code;
|
|
g->codes[init_code].suffix = (stbi_uc) init_code;
|
|
}
|
|
|
|
// support no starting clear code
|
|
avail = clear+2;
|
|
oldcode = -1;
|
|
|
|
len = 0;
|
|
for(;;) {
|
|
if (valid_bits < codesize) {
|
|
if (len == 0) {
|
|
len = stbi__get8(s); // start new block
|
|
if (len == 0)
|
|
return g->out;
|
|
}
|
|
--len;
|
|
bits |= (stbi__int32) stbi__get8(s) << valid_bits;
|
|
valid_bits += 8;
|
|
} else {
|
|
stbi__int32 code = bits & codemask;
|
|
bits >>= codesize;
|
|
valid_bits -= codesize;
|
|
// @OPTIMIZE: is there some way we can accelerate the non-clear path?
|
|
if (code == clear) { // clear code
|
|
codesize = lzw_cs + 1;
|
|
codemask = (1 << codesize) - 1;
|
|
avail = clear + 2;
|
|
oldcode = -1;
|
|
first = 0;
|
|
} else if (code == clear + 1) { // end of stream code
|
|
stbi__skip(s, len);
|
|
while ((len = stbi__get8(s)) > 0)
|
|
stbi__skip(s,len);
|
|
return g->out;
|
|
} else if (code <= avail) {
|
|
if (first) return stbi__errpuc("no clear code", "Corrupt GIF");
|
|
|
|
if (oldcode >= 0) {
|
|
p = &g->codes[avail++];
|
|
if (avail > 4096) return stbi__errpuc("too many codes", "Corrupt GIF");
|
|
p->prefix = (stbi__int16) oldcode;
|
|
p->first = g->codes[oldcode].first;
|
|
p->suffix = (code == avail) ? p->first : g->codes[code].first;
|
|
} else if (code == avail)
|
|
return stbi__errpuc("illegal code in raster", "Corrupt GIF");
|
|
|
|
stbi__out_gif_code(g, (stbi__uint16) code);
|
|
|
|
if ((avail & codemask) == 0 && avail <= 0x0FFF) {
|
|
codesize++;
|
|
codemask = (1 << codesize) - 1;
|
|
}
|
|
|
|
oldcode = code;
|
|
} else {
|
|
return stbi__errpuc("illegal code in raster", "Corrupt GIF");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void stbi__fill_gif_background(stbi__gif *g, int x0, int y0, int x1, int y1)
|
|
{
|
|
int x, y;
|
|
stbi_uc *c = g->pal[g->bgindex];
|
|
for (y = y0; y < y1; y += 4 * g->w) {
|
|
for (x = x0; x < x1; x += 4) {
|
|
stbi_uc *p = &g->out[y + x];
|
|
p[0] = c[2];
|
|
p[1] = c[1];
|
|
p[2] = c[0];
|
|
p[3] = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
// this function is designed to support animated gifs, although stb_image doesn't support it
|
|
static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, int req_comp)
|
|
{
|
|
int i;
|
|
stbi_uc *prev_out = 0;
|
|
|
|
if (g->out == 0 && !stbi__gif_header(s, g, comp,0))
|
|
return 0; // stbi__g_failure_reason set by stbi__gif_header
|
|
|
|
prev_out = g->out;
|
|
g->out = (stbi_uc *) stbi__malloc(4 * g->w * g->h);
|
|
if (g->out == 0) return stbi__errpuc("outofmem", "Out of memory");
|
|
|
|
switch ((g->eflags & 0x1C) >> 2) {
|
|
case 0: // unspecified (also always used on 1st frame)
|
|
stbi__fill_gif_background(g, 0, 0, 4 * g->w, 4 * g->w * g->h);
|
|
break;
|
|
case 1: // do not dispose
|
|
if (prev_out) memcpy(g->out, prev_out, 4 * g->w * g->h);
|
|
g->old_out = prev_out;
|
|
break;
|
|
case 2: // dispose to background
|
|
if (prev_out) memcpy(g->out, prev_out, 4 * g->w * g->h);
|
|
stbi__fill_gif_background(g, g->start_x, g->start_y, g->max_x, g->max_y);
|
|
break;
|
|
case 3: // dispose to previous
|
|
if (g->old_out) {
|
|
for (i = g->start_y; i < g->max_y; i += 4 * g->w)
|
|
memcpy(&g->out[i + g->start_x], &g->old_out[i + g->start_x], g->max_x - g->start_x);
|
|
}
|
|
break;
|
|
}
|
|
|
|
for (;;) {
|
|
switch (stbi__get8(s)) {
|
|
case 0x2C: /* Image Descriptor */
|
|
{
|
|
int prev_trans = -1;
|
|
stbi__int32 x, y, w, h;
|
|
stbi_uc *o;
|
|
|
|
x = stbi__get16le(s);
|
|
y = stbi__get16le(s);
|
|
w = stbi__get16le(s);
|
|
h = stbi__get16le(s);
|
|
if (((x + w) > (g->w)) || ((y + h) > (g->h)))
|
|
return stbi__errpuc("bad Image Descriptor", "Corrupt GIF");
|
|
|
|
g->line_size = g->w * 4;
|
|
g->start_x = x * 4;
|
|
g->start_y = y * g->line_size;
|
|
g->max_x = g->start_x + w * 4;
|
|
g->max_y = g->start_y + h * g->line_size;
|
|
g->cur_x = g->start_x;
|
|
g->cur_y = g->start_y;
|
|
|
|
g->lflags = stbi__get8(s);
|
|
|
|
if (g->lflags & 0x40) {
|
|
g->step = 8 * g->line_size; // first interlaced spacing
|
|
g->parse = 3;
|
|
} else {
|
|
g->step = g->line_size;
|
|
g->parse = 0;
|
|
}
|
|
|
|
if (g->lflags & 0x80) {
|
|
stbi__gif_parse_colortable(s,g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1);
|
|
g->color_table = (stbi_uc *) g->lpal;
|
|
} else if (g->flags & 0x80) {
|
|
if (g->transparent >= 0 && (g->eflags & 0x01)) {
|
|
prev_trans = g->pal[g->transparent][3];
|
|
g->pal[g->transparent][3] = 0;
|
|
}
|
|
g->color_table = (stbi_uc *) g->pal;
|
|
} else
|
|
return stbi__errpuc("missing color table", "Corrupt GIF");
|
|
|
|
o = stbi__process_gif_raster(s, g);
|
|
if (o == NULL) return NULL;
|
|
|
|
if (prev_trans != -1)
|
|
g->pal[g->transparent][3] = (stbi_uc) prev_trans;
|
|
|
|
return o;
|
|
}
|
|
|
|
case 0x21: // Comment Extension.
|
|
{
|
|
int len;
|
|
if (stbi__get8(s) == 0xF9) { // Graphic Control Extension.
|
|
len = stbi__get8(s);
|
|
if (len == 4) {
|
|
g->eflags = stbi__get8(s);
|
|
g->delay = stbi__get16le(s);
|
|
g->transparent = stbi__get8(s);
|
|
} else {
|
|
stbi__skip(s, len);
|
|
break;
|
|
}
|
|
}
|
|
while ((len = stbi__get8(s)) != 0)
|
|
stbi__skip(s, len);
|
|
break;
|
|
}
|
|
|
|
case 0x3B: // gif stream termination code
|
|
return (stbi_uc *) s; // using '1' causes warning on some compilers
|
|
|
|
default:
|
|
return stbi__errpuc("unknown code", "Corrupt GIF");
|
|
}
|
|
}
|
|
|
|
STBI_NOTUSED(req_comp);
|
|
}
|
|
|
|
static stbi_uc *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *u = 0;
|
|
stbi__gif* g = (stbi__gif*) stbi__malloc(sizeof(stbi__gif));
|
|
memset(g, 0, sizeof(*g));
|
|
|
|
u = stbi__gif_load_next(s, g, comp, req_comp);
|
|
if (u == (stbi_uc *) s) u = 0; // end of animated gif marker
|
|
if (u) {
|
|
*x = g->w;
|
|
*y = g->h;
|
|
if (req_comp && req_comp != 4)
|
|
u = stbi__convert_format(u, 4, req_comp, g->w, g->h);
|
|
}
|
|
else if (g->out)
|
|
STBI_FREE(g->out);
|
|
STBI_FREE(g);
|
|
return u;
|
|
}
|
|
|
|
static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
return stbi__gif_info_raw(s,x,y,comp);
|
|
}
|
|
#endif
|
|
|
|
// *************************************************************************************************
|
|
// Radiance RGBE HDR loader
|
|
// originally by Nicolas Schulz
|
|
#ifndef STBI_NO_HDR
|
|
static int stbi__hdr_test_core(stbi__context *s)
|
|
{
|
|
const char *signature = "#?RADIANCE\n";
|
|
int i;
|
|
for (i=0; signature[i]; ++i)
|
|
if (stbi__get8(s) != signature[i])
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int stbi__hdr_test(stbi__context* s)
|
|
{
|
|
int r = stbi__hdr_test_core(s);
|
|
stbi__rewind(s);
|
|
return r;
|
|
}
|
|
|
|
#define STBI__HDR_BUFLEN 1024
|
|
static char *stbi__hdr_gettoken(stbi__context *z, char *buffer)
|
|
{
|
|
int len=0;
|
|
char c = '\0';
|
|
|
|
c = (char) stbi__get8(z);
|
|
|
|
while (!stbi__at_eof(z) && c != '\n') {
|
|
buffer[len++] = c;
|
|
if (len == STBI__HDR_BUFLEN-1) {
|
|
// flush to end of line
|
|
while (!stbi__at_eof(z) && stbi__get8(z) != '\n')
|
|
;
|
|
break;
|
|
}
|
|
c = (char) stbi__get8(z);
|
|
}
|
|
|
|
buffer[len] = 0;
|
|
return buffer;
|
|
}
|
|
|
|
static void stbi__hdr_convert(float *output, stbi_uc *input, int req_comp)
|
|
{
|
|
if ( input[3] != 0 ) {
|
|
float f1;
|
|
// Exponent
|
|
f1 = (float) ldexp(1.0f, input[3] - (int)(128 + 8));
|
|
if (req_comp <= 2)
|
|
output[0] = (input[0] + input[1] + input[2]) * f1 / 3;
|
|
else {
|
|
output[0] = input[0] * f1;
|
|
output[1] = input[1] * f1;
|
|
output[2] = input[2] * f1;
|
|
}
|
|
if (req_comp == 2) output[1] = 1;
|
|
if (req_comp == 4) output[3] = 1;
|
|
} else {
|
|
switch (req_comp) {
|
|
case 4: output[3] = 1; /* fallthrough */
|
|
case 3: output[0] = output[1] = output[2] = 0;
|
|
break;
|
|
case 2: output[1] = 1; /* fallthrough */
|
|
case 1: output[0] = 0;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
char buffer[STBI__HDR_BUFLEN];
|
|
char *token;
|
|
int valid = 0;
|
|
int width, height;
|
|
stbi_uc *scanline;
|
|
float *hdr_data;
|
|
int len;
|
|
unsigned char count, value;
|
|
int i, j, k, c1,c2, z;
|
|
|
|
|
|
// Check identifier
|
|
if (strcmp(stbi__hdr_gettoken(s,buffer), "#?RADIANCE") != 0)
|
|
return stbi__errpf("not HDR", "Corrupt HDR image");
|
|
|
|
// Parse header
|
|
for(;;) {
|
|
token = stbi__hdr_gettoken(s,buffer);
|
|
if (token[0] == 0) break;
|
|
if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
|
|
}
|
|
|
|
if (!valid) return stbi__errpf("unsupported format", "Unsupported HDR format");
|
|
|
|
// Parse width and height
|
|
// can't use sscanf() if we're not using stdio!
|
|
token = stbi__hdr_gettoken(s,buffer);
|
|
if (strncmp(token, "-Y ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format");
|
|
token += 3;
|
|
height = (int) strtol(token, &token, 10);
|
|
while (*token == ' ') ++token;
|
|
if (strncmp(token, "+X ", 3)) return stbi__errpf("unsupported data layout", "Unsupported HDR format");
|
|
token += 3;
|
|
width = (int) strtol(token, NULL, 10);
|
|
|
|
*x = width;
|
|
*y = height;
|
|
|
|
if (comp) *comp = 3;
|
|
if (req_comp == 0) req_comp = 3;
|
|
|
|
// Read data
|
|
hdr_data = (float *) stbi__malloc(height * width * req_comp * sizeof(float));
|
|
|
|
// Load image data
|
|
// image data is stored as some number of sca
|
|
if ( width < 8 || width >= 32768) {
|
|
// Read flat data
|
|
for (j=0; j < height; ++j) {
|
|
for (i=0; i < width; ++i) {
|
|
stbi_uc rgbe[4];
|
|
main_decode_loop:
|
|
stbi__getn(s, rgbe, 4);
|
|
stbi__hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp);
|
|
}
|
|
}
|
|
} else {
|
|
// Read RLE-encoded data
|
|
scanline = NULL;
|
|
|
|
for (j = 0; j < height; ++j) {
|
|
c1 = stbi__get8(s);
|
|
c2 = stbi__get8(s);
|
|
len = stbi__get8(s);
|
|
if (c1 != 2 || c2 != 2 || (len & 0x80)) {
|
|
// not run-length encoded, so we have to actually use THIS data as a decoded
|
|
// pixel (note this can't be a valid pixel--one of RGB must be >= 128)
|
|
stbi_uc rgbe[4];
|
|
rgbe[0] = (stbi_uc) c1;
|
|
rgbe[1] = (stbi_uc) c2;
|
|
rgbe[2] = (stbi_uc) len;
|
|
rgbe[3] = (stbi_uc) stbi__get8(s);
|
|
stbi__hdr_convert(hdr_data, rgbe, req_comp);
|
|
i = 1;
|
|
j = 0;
|
|
STBI_FREE(scanline);
|
|
goto main_decode_loop; // yes, this makes no sense
|
|
}
|
|
len <<= 8;
|
|
len |= stbi__get8(s);
|
|
if (len != width) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("invalid decoded scanline length", "corrupt HDR"); }
|
|
if (scanline == NULL) scanline = (stbi_uc *) stbi__malloc(width * 4);
|
|
|
|
for (k = 0; k < 4; ++k) {
|
|
i = 0;
|
|
while (i < width) {
|
|
count = stbi__get8(s);
|
|
if (count > 128) {
|
|
// Run
|
|
value = stbi__get8(s);
|
|
count -= 128;
|
|
for (z = 0; z < count; ++z)
|
|
scanline[i++ * 4 + k] = value;
|
|
} else {
|
|
// Dump
|
|
for (z = 0; z < count; ++z)
|
|
scanline[i++ * 4 + k] = stbi__get8(s);
|
|
}
|
|
}
|
|
}
|
|
for (i=0; i < width; ++i)
|
|
stbi__hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp);
|
|
}
|
|
STBI_FREE(scanline);
|
|
}
|
|
|
|
return hdr_data;
|
|
}
|
|
|
|
static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
char buffer[STBI__HDR_BUFLEN];
|
|
char *token;
|
|
int valid = 0;
|
|
|
|
if (stbi__hdr_test(s) == 0) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
|
|
for(;;) {
|
|
token = stbi__hdr_gettoken(s,buffer);
|
|
if (token[0] == 0) break;
|
|
if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
|
|
}
|
|
|
|
if (!valid) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
token = stbi__hdr_gettoken(s,buffer);
|
|
if (strncmp(token, "-Y ", 3)) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
token += 3;
|
|
*y = (int) strtol(token, &token, 10);
|
|
while (*token == ' ') ++token;
|
|
if (strncmp(token, "+X ", 3)) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
token += 3;
|
|
*x = (int) strtol(token, NULL, 10);
|
|
*comp = 3;
|
|
return 1;
|
|
}
|
|
#endif // STBI_NO_HDR
|
|
|
|
#ifndef STBI_NO_BMP
|
|
static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
void *p;
|
|
stbi__bmp_data info;
|
|
|
|
info.all_a = 255;
|
|
p = stbi__bmp_parse_header(s, &info);
|
|
stbi__rewind( s );
|
|
if (p == NULL)
|
|
return 0;
|
|
*x = s->img_x;
|
|
*y = s->img_y;
|
|
*comp = info.ma ? 4 : 3;
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PSD
|
|
static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
int channelCount;
|
|
if (stbi__get32be(s) != 0x38425053) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
if (stbi__get16be(s) != 1) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
stbi__skip(s, 6);
|
|
channelCount = stbi__get16be(s);
|
|
if (channelCount < 0 || channelCount > 16) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
*y = stbi__get32be(s);
|
|
*x = stbi__get32be(s);
|
|
if (stbi__get16be(s) != 8) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
if (stbi__get16be(s) != 3) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
*comp = 4;
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PIC
|
|
static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
int act_comp=0,num_packets=0,chained;
|
|
stbi__pic_packet packets[10];
|
|
|
|
if (!stbi__pic_is4(s,"\x53\x80\xF6\x34")) {
|
|
stbi__rewind(s);
|
|
return 0;
|
|
}
|
|
|
|
stbi__skip(s, 88);
|
|
|
|
*x = stbi__get16be(s);
|
|
*y = stbi__get16be(s);
|
|
if (stbi__at_eof(s)) {
|
|
stbi__rewind( s);
|
|
return 0;
|
|
}
|
|
if ( (*x) != 0 && (1 << 28) / (*x) < (*y)) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
|
|
stbi__skip(s, 8);
|
|
|
|
do {
|
|
stbi__pic_packet *packet;
|
|
|
|
if (num_packets==sizeof(packets)/sizeof(packets[0]))
|
|
return 0;
|
|
|
|
packet = &packets[num_packets++];
|
|
chained = stbi__get8(s);
|
|
packet->size = stbi__get8(s);
|
|
packet->type = stbi__get8(s);
|
|
packet->channel = stbi__get8(s);
|
|
act_comp |= packet->channel;
|
|
|
|
if (stbi__at_eof(s)) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
if (packet->size != 8) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
} while (chained);
|
|
|
|
*comp = (act_comp & 0x10 ? 4 : 3);
|
|
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
// *************************************************************************************************
|
|
// Portable Gray Map and Portable Pixel Map loader
|
|
// by Ken Miller
|
|
//
|
|
// PGM: http://netpbm.sourceforge.net/doc/pgm.html
|
|
// PPM: http://netpbm.sourceforge.net/doc/ppm.html
|
|
//
|
|
// Known limitations:
|
|
// Does not support comments in the header section
|
|
// Does not support ASCII image data (formats P2 and P3)
|
|
// Does not support 16-bit-per-channel
|
|
|
|
#ifndef STBI_NO_PNM
|
|
|
|
static int stbi__pnm_test(stbi__context *s)
|
|
{
|
|
char p, t;
|
|
p = (char) stbi__get8(s);
|
|
t = (char) stbi__get8(s);
|
|
if (p != 'P' || (t != '5' && t != '6')) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static stbi_uc *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *out;
|
|
if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n))
|
|
return 0;
|
|
*x = s->img_x;
|
|
*y = s->img_y;
|
|
*comp = s->img_n;
|
|
|
|
out = (stbi_uc *) stbi__malloc(s->img_n * s->img_x * s->img_y);
|
|
if (!out) return stbi__errpuc("outofmem", "Out of memory");
|
|
stbi__getn(s, out, s->img_n * s->img_x * s->img_y);
|
|
|
|
if (req_comp && req_comp != s->img_n) {
|
|
out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y);
|
|
if (out == NULL) return out; // stbi__convert_format frees input on failure
|
|
}
|
|
return out;
|
|
}
|
|
|
|
static int stbi__pnm_isspace(char c)
|
|
{
|
|
return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r';
|
|
}
|
|
|
|
static void stbi__pnm_skip_whitespace(stbi__context *s, char *c)
|
|
{
|
|
for (;;) {
|
|
while (!stbi__at_eof(s) && stbi__pnm_isspace(*c))
|
|
*c = (char) stbi__get8(s);
|
|
|
|
if (stbi__at_eof(s) || *c != '#')
|
|
break;
|
|
|
|
while (!stbi__at_eof(s) && *c != '\n' && *c != '\r' )
|
|
*c = (char) stbi__get8(s);
|
|
}
|
|
}
|
|
|
|
static int stbi__pnm_isdigit(char c)
|
|
{
|
|
return c >= '0' && c <= '9';
|
|
}
|
|
|
|
static int stbi__pnm_getinteger(stbi__context *s, char *c)
|
|
{
|
|
int value = 0;
|
|
|
|
while (!stbi__at_eof(s) && stbi__pnm_isdigit(*c)) {
|
|
value = value*10 + (*c - '0');
|
|
*c = (char) stbi__get8(s);
|
|
}
|
|
|
|
return value;
|
|
}
|
|
|
|
static int stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
int maxv;
|
|
char c, p, t;
|
|
|
|
stbi__rewind( s );
|
|
|
|
// Get identifier
|
|
p = (char) stbi__get8(s);
|
|
t = (char) stbi__get8(s);
|
|
if (p != 'P' || (t != '5' && t != '6')) {
|
|
stbi__rewind( s );
|
|
return 0;
|
|
}
|
|
|
|
*comp = (t == '6') ? 3 : 1; // '5' is 1-component .pgm; '6' is 3-component .ppm
|
|
|
|
c = (char) stbi__get8(s);
|
|
stbi__pnm_skip_whitespace(s, &c);
|
|
|
|
*x = stbi__pnm_getinteger(s, &c); // read width
|
|
stbi__pnm_skip_whitespace(s, &c);
|
|
|
|
*y = stbi__pnm_getinteger(s, &c); // read height
|
|
stbi__pnm_skip_whitespace(s, &c);
|
|
|
|
maxv = stbi__pnm_getinteger(s, &c); // read max value
|
|
|
|
if (maxv > 255)
|
|
return stbi__err("max value > 255", "PPM image not 8-bit");
|
|
else
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp)
|
|
{
|
|
#ifndef STBI_NO_JPEG
|
|
if (stbi__jpeg_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PNG
|
|
if (stbi__png_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_GIF
|
|
if (stbi__gif_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_BMP
|
|
if (stbi__bmp_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PSD
|
|
if (stbi__psd_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PIC
|
|
if (stbi__pic_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_PNM
|
|
if (stbi__pnm_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi__hdr_info(s, x, y, comp)) return 1;
|
|
#endif
|
|
|
|
// test tga last because it's a crappy test!
|
|
#ifndef STBI_NO_TGA
|
|
if (stbi__tga_info(s, x, y, comp))
|
|
return 1;
|
|
#endif
|
|
return stbi__err("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
STBIDEF int stbi_info(char const *filename, int *x, int *y, int *comp)
|
|
{
|
|
FILE *f = stbi__fopen(filename, "rb");
|
|
int result;
|
|
if (!f) return stbi__err("can't fopen", "Unable to open file");
|
|
result = stbi_info_from_file(f, x, y, comp);
|
|
fclose(f);
|
|
return result;
|
|
}
|
|
|
|
STBIDEF int stbi_info_from_file(FILE *f, int *x, int *y, int *comp)
|
|
{
|
|
int r;
|
|
stbi__context s;
|
|
long pos = ftell(f);
|
|
stbi__start_file(&s, f);
|
|
r = stbi__info_main(&s,x,y,comp);
|
|
fseek(f,pos,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif // !STBI_NO_STDIO
|
|
|
|
STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_mem(&s,buffer,len);
|
|
return stbi__info_main(&s,x,y,comp);
|
|
}
|
|
|
|
STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int *x, int *y, int *comp)
|
|
{
|
|
stbi__context s;
|
|
stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user);
|
|
return stbi__info_main(&s,x,y,comp);
|
|
}
|
|
|
|
#endif // STB_IMAGE_IMPLEMENTATION
|
|
|
|
/*
|
|
revision history:
|
|
2.12 (2016-04-02) fix typo in 2.11 PSD fix that caused crashes
|
|
2.11 (2016-04-02) allocate large structures on the stack
|
|
remove white matting for transparent PSD
|
|
fix reported channel count for PNG & BMP
|
|
re-enable SSE2 in non-gcc 64-bit
|
|
support RGB-formatted JPEG
|
|
read 16-bit PNGs (only as 8-bit)
|
|
2.10 (2016-01-22) avoid warning introduced in 2.09 by STBI_REALLOC_SIZED
|
|
2.09 (2016-01-16) allow comments in PNM files
|
|
16-bit-per-pixel TGA (not bit-per-component)
|
|
info() for TGA could break due to .hdr handling
|
|
info() for BMP to shares code instead of sloppy parse
|
|
can use STBI_REALLOC_SIZED if allocator doesn't support realloc
|
|
code cleanup
|
|
2.08 (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA
|
|
2.07 (2015-09-13) fix compiler warnings
|
|
partial animated GIF support
|
|
limited 16-bpc PSD support
|
|
#ifdef unused functions
|
|
bug with < 92 byte PIC,PNM,HDR,TGA
|
|
2.06 (2015-04-19) fix bug where PSD returns wrong '*comp' value
|
|
2.05 (2015-04-19) fix bug in progressive JPEG handling, fix warning
|
|
2.04 (2015-04-15) try to re-enable SIMD on MinGW 64-bit
|
|
2.03 (2015-04-12) extra corruption checking (mmozeiko)
|
|
stbi_set_flip_vertically_on_load (nguillemot)
|
|
fix NEON support; fix mingw support
|
|
2.02 (2015-01-19) fix incorrect assert, fix warning
|
|
2.01 (2015-01-17) fix various warnings; suppress SIMD on gcc 32-bit without -msse2
|
|
2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG
|
|
2.00 (2014-12-25) optimize JPG, including x86 SSE2 & NEON SIMD (ryg)
|
|
progressive JPEG (stb)
|
|
PGM/PPM support (Ken Miller)
|
|
STBI_MALLOC,STBI_REALLOC,STBI_FREE
|
|
GIF bugfix -- seemingly never worked
|
|
STBI_NO_*, STBI_ONLY_*
|
|
1.48 (2014-12-14) fix incorrectly-named assert()
|
|
1.47 (2014-12-14) 1/2/4-bit PNG support, both direct and paletted (Omar Cornut & stb)
|
|
optimize PNG (ryg)
|
|
fix bug in interlaced PNG with user-specified channel count (stb)
|
|
1.46 (2014-08-26)
|
|
fix broken tRNS chunk (colorkey-style transparency) in non-paletted PNG
|
|
1.45 (2014-08-16)
|
|
fix MSVC-ARM internal compiler error by wrapping malloc
|
|
1.44 (2014-08-07)
|
|
various warning fixes from Ronny Chevalier
|
|
1.43 (2014-07-15)
|
|
fix MSVC-only compiler problem in code changed in 1.42
|
|
1.42 (2014-07-09)
|
|
don't define _CRT_SECURE_NO_WARNINGS (affects user code)
|
|
fixes to stbi__cleanup_jpeg path
|
|
added STBI_ASSERT to avoid requiring assert.h
|
|
1.41 (2014-06-25)
|
|
fix search&replace from 1.36 that messed up comments/error messages
|
|
1.40 (2014-06-22)
|
|
fix gcc struct-initialization warning
|
|
1.39 (2014-06-15)
|
|
fix to TGA optimization when req_comp != number of components in TGA;
|
|
fix to GIF loading because BMP wasn't rewinding (whoops, no GIFs in my test suite)
|
|
add support for BMP version 5 (more ignored fields)
|
|
1.38 (2014-06-06)
|
|
suppress MSVC warnings on integer casts truncating values
|
|
fix accidental rename of 'skip' field of I/O
|
|
1.37 (2014-06-04)
|
|
remove duplicate typedef
|
|
1.36 (2014-06-03)
|
|
convert to header file single-file library
|
|
if de-iphone isn't set, load iphone images color-swapped instead of returning NULL
|
|
1.35 (2014-05-27)
|
|
various warnings
|
|
fix broken STBI_SIMD path
|
|
fix bug where stbi_load_from_file no longer left file pointer in correct place
|
|
fix broken non-easy path for 32-bit BMP (possibly never used)
|
|
TGA optimization by Arseny Kapoulkine
|
|
1.34 (unknown)
|
|
use STBI_NOTUSED in stbi__resample_row_generic(), fix one more leak in tga failure case
|
|
1.33 (2011-07-14)
|
|
make stbi_is_hdr work in STBI_NO_HDR (as specified), minor compiler-friendly improvements
|
|
1.32 (2011-07-13)
|
|
support for "info" function for all supported filetypes (SpartanJ)
|
|
1.31 (2011-06-20)
|
|
a few more leak fixes, bug in PNG handling (SpartanJ)
|
|
1.30 (2011-06-11)
|
|
added ability to load files via callbacks to accomidate custom input streams (Ben Wenger)
|
|
removed deprecated format-specific test/load functions
|
|
removed support for installable file formats (stbi_loader) -- would have been broken for IO callbacks anyway
|
|
error cases in bmp and tga give messages and don't leak (Raymond Barbiero, grisha)
|
|
fix inefficiency in decoding 32-bit BMP (David Woo)
|
|
1.29 (2010-08-16)
|
|
various warning fixes from Aurelien Pocheville
|
|
1.28 (2010-08-01)
|
|
fix bug in GIF palette transparency (SpartanJ)
|
|
1.27 (2010-08-01)
|
|
cast-to-stbi_uc to fix warnings
|
|
1.26 (2010-07-24)
|
|
fix bug in file buffering for PNG reported by SpartanJ
|
|
1.25 (2010-07-17)
|
|
refix trans_data warning (Won Chun)
|
|
1.24 (2010-07-12)
|
|
perf improvements reading from files on platforms with lock-heavy fgetc()
|
|
minor perf improvements for jpeg
|
|
deprecated type-specific functions so we'll get feedback if they're needed
|
|
attempt to fix trans_data warning (Won Chun)
|
|
1.23 fixed bug in iPhone support
|
|
1.22 (2010-07-10)
|
|
removed image *writing* support
|
|
stbi_info support from Jetro Lauha
|
|
GIF support from Jean-Marc Lienher
|
|
iPhone PNG-extensions from James Brown
|
|
warning-fixes from Nicolas Schulz and Janez Zemva (i.stbi__err. Janez (U+017D)emva)
|
|
1.21 fix use of 'stbi_uc' in header (reported by jon blow)
|
|
1.20 added support for Softimage PIC, by Tom Seddon
|
|
1.19 bug in interlaced PNG corruption check (found by ryg)
|
|
1.18 (2008-08-02)
|
|
fix a threading bug (local mutable static)
|
|
1.17 support interlaced PNG
|
|
1.16 major bugfix - stbi__convert_format converted one too many pixels
|
|
1.15 initialize some fields for thread safety
|
|
1.14 fix threadsafe conversion bug
|
|
header-file-only version (#define STBI_HEADER_FILE_ONLY before including)
|
|
1.13 threadsafe
|
|
1.12 const qualifiers in the API
|
|
1.11 Support installable IDCT, colorspace conversion routines
|
|
1.10 Fixes for 64-bit (don't use "unsigned long")
|
|
optimized upsampling by Fabian "ryg" Giesen
|
|
1.09 Fix format-conversion for PSD code (bad global variables!)
|
|
1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz
|
|
1.07 attempt to fix C++ warning/errors again
|
|
1.06 attempt to fix C++ warning/errors again
|
|
1.05 fix TGA loading to return correct *comp and use good luminance calc
|
|
1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free
|
|
1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR
|
|
1.02 support for (subset of) HDR files, float interface for preferred access to them
|
|
1.01 fix bug: possible bug in handling right-side up bmps... not sure
|
|
fix bug: the stbi__bmp_load() and stbi__tga_load() functions didn't work at all
|
|
1.00 interface to zlib that skips zlib header
|
|
0.99 correct handling of alpha in palette
|
|
0.98 TGA loader by lonesock; dynamically add loaders (untested)
|
|
0.97 jpeg errors on too large a file; also catch another malloc failure
|
|
0.96 fix detection of invalid v value - particleman@mollyrocket forum
|
|
0.95 during header scan, seek to markers in case of padding
|
|
0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same
|
|
0.93 handle jpegtran output; verbose errors
|
|
0.92 read 4,8,16,24,32-bit BMP files of several formats
|
|
0.91 output 24-bit Windows 3.0 BMP files
|
|
0.90 fix a few more warnings; bump version number to approach 1.0
|
|
0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd
|
|
0.60 fix compiling as c++
|
|
0.59 fix warnings: merge Dave Moore's -Wall fixes
|
|
0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian
|
|
0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less than 16 available
|
|
0.56 fix bug: zlib uncompressed mode len vs. nlen
|
|
0.55 fix bug: restart_interval not initialized to 0
|
|
0.54 allow NULL for 'int *comp'
|
|
0.53 fix bug in png 3->4; speedup png decoding
|
|
0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments
|
|
0.51 obey req_comp requests, 1-component jpegs return as 1-component,
|
|
on 'test' only check type, not whether we support this variant
|
|
0.50 (2006-11-19)
|
|
first released version
|
|
*/
|