3892 lines
122 KiB
C
3892 lines
122 KiB
C
/* stbi-1.18 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c
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when you control the images you're loading
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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 (no JPEG progressive, no oddball channel decimations)
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PNG 8-bit only
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BMP non-1bpp, non-RLE
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TGA (not sure what subset, if a subset)
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PSD (composited view only, no extra channels)
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HDR (radiance rgbE format)
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writes BMP,TGA (define STBI_NO_WRITE to remove code)
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decoded from memory or through stdio FILE (define STBI_NO_STDIO to remove code)
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supports installable dequantizing-IDCT, YCbCr-to-RGB conversion (define STBI_SIMD)
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TODO:
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stbi_info_*
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history:
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1.18 fix a threading bug (local mutable static)
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1.17 support interlaced PNG
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1.16 major bugfix - convert_format converted one too many pixels
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1.15 initialize some fields for thread safety
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1.14 fix threadsafe conversion bug; header-file-only version (#define STBI_HEADER_FILE_ONLY before including)
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1.13 threadsafe
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1.12 const qualifiers in the API
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1.11 Support installable IDCT, colorspace conversion routines
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1.10 Fixes for 64-bit (don't use "unsigned long")
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optimized upsampling by Fabian "ryg" Giesen
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1.09 Fix format-conversion for PSD code (bad global variables!)
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1.08 Thatcher Ulrich's PSD code integrated by Nicolas Schulz
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1.07 attempt to fix C++ warning/errors again
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1.06 attempt to fix C++ warning/errors again
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1.05 fix TGA loading to return correct *comp and use good luminance calc
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1.04 default float alpha is 1, not 255; use 'void *' for stbi_image_free
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1.03 bugfixes to STBI_NO_STDIO, STBI_NO_HDR
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1.02 support for (subset of) HDR files, float interface for preferred access to them
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1.01 fix bug: possible bug in handling right-side up bmps... not sure
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fix bug: the stbi_bmp_load() and stbi_tga_load() functions didn't work at all
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1.00 interface to zlib that skips zlib header
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0.99 correct handling of alpha in palette
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0.98 TGA loader by lonesock; dynamically add loaders (untested)
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0.97 jpeg errors on too large a file; also catch another malloc failure
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0.96 fix detection of invalid v value - particleman@mollyrocket forum
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0.95 during header scan, seek to markers in case of padding
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0.94 STBI_NO_STDIO to disable stdio usage; rename all #defines the same
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0.93 handle jpegtran output; verbose errors
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0.92 read 4,8,16,24,32-bit BMP files of several formats
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0.91 output 24-bit Windows 3.0 BMP files
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0.90 fix a few more warnings; bump version number to approach 1.0
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0.61 bugfixes due to Marc LeBlanc, Christopher Lloyd
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0.60 fix compiling as c++
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0.59 fix warnings: merge Dave Moore's -Wall fixes
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0.58 fix bug: zlib uncompressed mode len/nlen was wrong endian
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0.57 fix bug: jpg last huffman symbol before marker was >9 bits but less
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than 16 available
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0.56 fix bug: zlib uncompressed mode len vs. nlen
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0.55 fix bug: restart_interval not initialized to 0
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0.54 allow NULL for 'int *comp'
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0.53 fix bug in png 3->4; speedup png decoding
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0.52 png handles req_comp=3,4 directly; minor cleanup; jpeg comments
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0.51 obey req_comp requests, 1-component jpegs return as 1-component,
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on 'test' only check type, not whether we support this variant
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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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//// begin header file ////////////////////////////////////////////////////
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//
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// Limitations:
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// - no progressive/interlaced support (jpeg, png)
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// - 8-bit samples only (jpeg, png)
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// - not threadsafe
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// - channel subsampling of at most 2 in each dimension (jpeg)
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// - no delayed line count (jpeg) -- IJG doesn't support either
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//
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// Basic usage (see HDR discussion below):
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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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// 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. 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 easily see if it's opaque.
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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 and BMP images are automatically depalettized.
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//
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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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#ifndef STBI_NO_STDIO
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#include <stdio.h>
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#endif
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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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// WRITING API
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#if !defined(STBI_NO_WRITE) && !defined(STBI_NO_STDIO)
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// write a BMP/TGA file given tightly packed 'comp' channels (no padding, nor bmp-stride-padding)
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// (you must include the appropriate extension in the filename).
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// returns TRUE on success, FALSE if couldn't open file, error writing file
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extern int stbi_write_bmp (char const *filename, int x, int y, int comp, void *data);
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extern int stbi_write_tga (char const *filename, int x, int y, int comp, void *data);
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#endif
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// PRIMARY API - works on images of any type
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// load image by filename, open file, or memory buffer
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#ifndef STBI_NO_STDIO
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extern stbi_uc *stbi_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp);
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#endif
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extern 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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// for stbi_load_from_file, file pointer is left pointing immediately after image
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#ifndef STBI_NO_HDR
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#ifndef STBI_NO_STDIO
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extern float *stbi_loadf (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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#endif
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extern float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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extern void stbi_hdr_to_ldr_gamma(float gamma);
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extern void stbi_hdr_to_ldr_scale(float scale);
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extern void stbi_ldr_to_hdr_gamma(float gamma);
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extern void stbi_ldr_to_hdr_scale(float scale);
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#endif // STBI_NO_HDR
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// get a VERY brief reason for failure
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// NOT THREADSAFE
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extern char *stbi_failure_reason (void);
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// free the loaded image -- this is just free()
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extern void stbi_image_free (void *retval_from_stbi_load);
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// get image dimensions & components without fully decoding
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extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
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extern int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len);
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#ifndef STBI_NO_STDIO
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extern int stbi_info (char const *filename, int *x, int *y, int *comp);
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extern int stbi_is_hdr (char const *filename);
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extern int stbi_is_hdr_from_file(FILE *f);
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#endif
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// ZLIB client - used by PNG, available for other purposes
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extern char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen);
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extern char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen);
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extern int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
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extern char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen);
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extern int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
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// TYPE-SPECIFIC ACCESS
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// is it a jpeg?
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extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len);
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extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
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#ifndef STBI_NO_STDIO
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extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern int stbi_jpeg_test_file (FILE *f);
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extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp);
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extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp);
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#endif
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// is it a png?
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extern int stbi_png_test_memory (stbi_uc const *buffer, int len);
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extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp);
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#ifndef STBI_NO_STDIO
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extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern int stbi_png_info (char const *filename, int *x, int *y, int *comp);
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extern int stbi_png_test_file (FILE *f);
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extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp);
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#endif
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// is it a bmp?
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extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len);
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extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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#ifndef STBI_NO_STDIO
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extern int stbi_bmp_test_file (FILE *f);
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extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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#endif
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// is it a tga?
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extern int stbi_tga_test_memory (stbi_uc const *buffer, int len);
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extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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#ifndef STBI_NO_STDIO
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extern int stbi_tga_test_file (FILE *f);
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extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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#endif
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// is it a psd?
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extern int stbi_psd_test_memory (stbi_uc const *buffer, int len);
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extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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#ifndef STBI_NO_STDIO
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extern int stbi_psd_test_file (FILE *f);
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extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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#endif
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// is it an hdr?
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extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len);
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extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp);
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extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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#ifndef STBI_NO_STDIO
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extern int stbi_hdr_test_file (FILE *f);
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extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
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#endif
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// define new loaders
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typedef struct
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{
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int (*test_memory)(stbi_uc const *buffer, int len);
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stbi_uc * (*load_from_memory)(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
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#ifndef STBI_NO_STDIO
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int (*test_file)(FILE *f);
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stbi_uc * (*load_from_file)(FILE *f, int *x, int *y, int *comp, int req_comp);
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#endif
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} stbi_loader;
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// register a loader by filling out the above structure (you must defined ALL functions)
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// returns 1 if added or already added, 0 if not added (too many loaders)
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// NOT THREADSAFE
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extern int stbi_register_loader(stbi_loader *loader);
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// define faster low-level operations (typically SIMD support)
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#if STBI_SIMD
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typedef void (*stbi_idct_8x8)(uint8 *out, int out_stride, short data[64], unsigned short *dequantize);
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// compute an integer IDCT on "input"
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// input[x] = data[x] * dequantize[x]
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// write results to 'out': 64 samples, each run of 8 spaced by 'out_stride'
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// CLAMP results to 0..255
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typedef void (*stbi_YCbCr_to_RGB_run)(uint8 *output, uint8 const *y, uint8 const *cb, uint8 const *cr, int count, int step);
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// compute a conversion from YCbCr to RGB
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// 'count' pixels
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// write pixels to 'output'; each pixel is 'step' bytes (either 3 or 4; if 4, write '255' as 4th), order R,G,B
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// y: Y input channel
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// cb: Cb input channel; scale/biased to be 0..255
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// cr: Cr input channel; scale/biased to be 0..255
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extern void stbi_install_idct(stbi_idct_8x8 func);
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extern void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func);
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#endif // STBI_SIMD
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#ifdef __cplusplus
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}
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#endif
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//
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//
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//// end header file /////////////////////////////////////////////////////
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#endif // STBI_INCLUDE_STB_IMAGE_H
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#ifndef STBI_HEADER_FILE_ONLY
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#ifndef STBI_NO_HDR
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#include <math.h> // ldexp
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#include <string.h> // strcmp
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#endif
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#ifndef STBI_NO_STDIO
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#include <stdio.h>
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#endif
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#include <stdlib.h>
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#include <memory.h>
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#include <assert.h>
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#include <stdarg.h>
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#ifndef _MSC_VER
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#ifdef __cplusplus
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#define __forceinline inline
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#else
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#define __forceinline
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#endif
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#endif
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// implementation:
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typedef unsigned char uint8;
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typedef unsigned short uint16;
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typedef signed short int16;
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typedef unsigned int uint32;
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typedef signed int int32;
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typedef unsigned int uint;
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// should produce compiler error if size is wrong
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typedef unsigned char validate_uint32[sizeof(uint32)==4];
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#if defined(STBI_NO_STDIO) && !defined(STBI_NO_WRITE)
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#define STBI_NO_WRITE
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#endif
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//////////////////////////////////////////////////////////////////////////////
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//
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// Generic API that works on all image types
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//
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// this is not threadsafe
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static char *failure_reason;
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char *stbi_failure_reason(void)
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{
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return failure_reason;
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}
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static int e(char *str)
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{
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failure_reason = str;
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return 0;
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}
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#ifdef STBI_NO_FAILURE_STRINGS
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#define e(x,y) 0
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#elif defined(STBI_FAILURE_USERMSG)
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#define e(x,y) e(y)
|
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#else
|
|
#define e(x,y) e(x)
|
|
#endif
|
|
|
|
#define epf(x,y) ((float *) (e(x,y)?NULL:NULL))
|
|
#define epuc(x,y) ((unsigned char *) (e(x,y)?NULL:NULL))
|
|
|
|
void stbi_image_free(void *retval_from_stbi_load)
|
|
{
|
|
free(retval_from_stbi_load);
|
|
}
|
|
|
|
#define MAX_LOADERS 32
|
|
stbi_loader *loaders[MAX_LOADERS];
|
|
static int max_loaders = 0;
|
|
|
|
int stbi_register_loader(stbi_loader *loader)
|
|
{
|
|
int i;
|
|
for (i=0; i < MAX_LOADERS; ++i) {
|
|
// already present?
|
|
if (loaders[i] == loader)
|
|
return 1;
|
|
// end of the list?
|
|
if (loaders[i] == NULL) {
|
|
loaders[i] = loader;
|
|
max_loaders = i+1;
|
|
return 1;
|
|
}
|
|
}
|
|
// no room for it
|
|
return 0;
|
|
}
|
|
|
|
#ifndef STBI_NO_HDR
|
|
static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp);
|
|
static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp);
|
|
#endif
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
unsigned char *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
FILE *f = fopen(filename, "rb");
|
|
unsigned char *result;
|
|
if (!f) return epuc("can't fopen", "Unable to open file");
|
|
result = stbi_load_from_file(f,x,y,comp,req_comp);
|
|
fclose(f);
|
|
return result;
|
|
}
|
|
|
|
unsigned char *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
int i;
|
|
if (stbi_jpeg_test_file(f))
|
|
return stbi_jpeg_load_from_file(f,x,y,comp,req_comp);
|
|
if (stbi_png_test_file(f))
|
|
return stbi_png_load_from_file(f,x,y,comp,req_comp);
|
|
if (stbi_bmp_test_file(f))
|
|
return stbi_bmp_load_from_file(f,x,y,comp,req_comp);
|
|
if (stbi_psd_test_file(f))
|
|
return stbi_psd_load_from_file(f,x,y,comp,req_comp);
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi_hdr_test_file(f)) {
|
|
float *hdr = stbi_hdr_load_from_file(f, x,y,comp,req_comp);
|
|
return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
|
|
}
|
|
#endif
|
|
for (i=0; i < max_loaders; ++i)
|
|
if (loaders[i]->test_file(f))
|
|
return loaders[i]->load_from_file(f,x,y,comp,req_comp);
|
|
// test tga last because it's a crappy test!
|
|
if (stbi_tga_test_file(f))
|
|
return stbi_tga_load_from_file(f,x,y,comp,req_comp);
|
|
return epuc("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
#endif
|
|
|
|
unsigned char *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
int i;
|
|
if (stbi_jpeg_test_memory(buffer,len))
|
|
return stbi_jpeg_load_from_memory(buffer,len,x,y,comp,req_comp);
|
|
if (stbi_png_test_memory(buffer,len))
|
|
return stbi_png_load_from_memory(buffer,len,x,y,comp,req_comp);
|
|
if (stbi_bmp_test_memory(buffer,len))
|
|
return stbi_bmp_load_from_memory(buffer,len,x,y,comp,req_comp);
|
|
if (stbi_psd_test_memory(buffer,len))
|
|
return stbi_psd_load_from_memory(buffer,len,x,y,comp,req_comp);
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi_hdr_test_memory(buffer, len)) {
|
|
float *hdr = stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp);
|
|
return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
|
|
}
|
|
#endif
|
|
for (i=0; i < max_loaders; ++i)
|
|
if (loaders[i]->test_memory(buffer,len))
|
|
return loaders[i]->load_from_memory(buffer,len,x,y,comp,req_comp);
|
|
// test tga last because it's a crappy test!
|
|
if (stbi_tga_test_memory(buffer,len))
|
|
return stbi_tga_load_from_memory(buffer,len,x,y,comp,req_comp);
|
|
return epuc("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
|
|
#ifndef STBI_NO_HDR
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
FILE *f = fopen(filename, "rb");
|
|
float *result;
|
|
if (!f) return epf("can't fopen", "Unable to open file");
|
|
result = stbi_loadf_from_file(f,x,y,comp,req_comp);
|
|
fclose(f);
|
|
return result;
|
|
}
|
|
|
|
float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char *data;
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi_hdr_test_file(f))
|
|
return stbi_hdr_load_from_file(f,x,y,comp,req_comp);
|
|
#endif
|
|
data = stbi_load_from_file(f, x, y, comp, req_comp);
|
|
if (data)
|
|
return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
|
|
return epf("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
#endif
|
|
|
|
float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *data;
|
|
#ifndef STBI_NO_HDR
|
|
if (stbi_hdr_test_memory(buffer, len))
|
|
return stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp);
|
|
#endif
|
|
data = stbi_load_from_memory(buffer, len, x, y, comp, req_comp);
|
|
if (data)
|
|
return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
|
|
return epf("unknown image type", "Image not of any known type, or corrupt");
|
|
}
|
|
#endif
|
|
|
|
// these is-hdr-or-not is defined independent of whether STBI_NO_HDR is
|
|
// defined, for API simplicity; if STBI_NO_HDR is defined, it always
|
|
// reports false!
|
|
|
|
int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len)
|
|
{
|
|
#ifndef STBI_NO_HDR
|
|
return stbi_hdr_test_memory(buffer, len);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
extern int stbi_is_hdr (char const *filename)
|
|
{
|
|
FILE *f = fopen(filename, "rb");
|
|
int result=0;
|
|
if (f) {
|
|
result = stbi_is_hdr_from_file(f);
|
|
fclose(f);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
extern int stbi_is_hdr_from_file(FILE *f)
|
|
{
|
|
#ifndef STBI_NO_HDR
|
|
return stbi_hdr_test_file(f);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
#endif
|
|
|
|
// @TODO: get image dimensions & components without fully decoding
|
|
#ifndef STBI_NO_STDIO
|
|
extern int stbi_info (char const *filename, int *x, int *y, int *comp);
|
|
extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp);
|
|
#endif
|
|
extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
|
|
|
|
#ifndef STBI_NO_HDR
|
|
static float h2l_gamma_i=1.0f/2.2f, h2l_scale_i=1.0f;
|
|
static float l2h_gamma=2.2f, l2h_scale=1.0f;
|
|
|
|
void stbi_hdr_to_ldr_gamma(float gamma) { h2l_gamma_i = 1/gamma; }
|
|
void stbi_hdr_to_ldr_scale(float scale) { h2l_scale_i = 1/scale; }
|
|
|
|
void stbi_ldr_to_hdr_gamma(float gamma) { l2h_gamma = gamma; }
|
|
void stbi_ldr_to_hdr_scale(float scale) { l2h_scale = scale; }
|
|
#endif
|
|
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Common code used by all image loaders
|
|
//
|
|
|
|
enum
|
|
{
|
|
SCAN_load=0,
|
|
SCAN_type,
|
|
SCAN_header,
|
|
};
|
|
|
|
typedef struct
|
|
{
|
|
uint32 img_x, img_y;
|
|
int img_n, img_out_n;
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
FILE *img_file;
|
|
#endif
|
|
uint8 *img_buffer, *img_buffer_end;
|
|
} stbi;
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
static void start_file(stbi *s, FILE *f)
|
|
{
|
|
s->img_file = f;
|
|
}
|
|
#endif
|
|
|
|
static void start_mem(stbi *s, uint8 const *buffer, int len)
|
|
{
|
|
#ifndef STBI_NO_STDIO
|
|
s->img_file = NULL;
|
|
#endif
|
|
s->img_buffer = (uint8 *) buffer;
|
|
s->img_buffer_end = (uint8 *) buffer+len;
|
|
}
|
|
|
|
__forceinline static int get8(stbi *s)
|
|
{
|
|
#ifndef STBI_NO_STDIO
|
|
if (s->img_file) {
|
|
int c = fgetc(s->img_file);
|
|
return c == EOF ? 0 : c;
|
|
}
|
|
#endif
|
|
if (s->img_buffer < s->img_buffer_end)
|
|
return *s->img_buffer++;
|
|
return 0;
|
|
}
|
|
|
|
__forceinline static int at_eof(stbi *s)
|
|
{
|
|
#ifndef STBI_NO_STDIO
|
|
if (s->img_file)
|
|
return feof(s->img_file);
|
|
#endif
|
|
return s->img_buffer >= s->img_buffer_end;
|
|
}
|
|
|
|
__forceinline static uint8 get8u(stbi *s)
|
|
{
|
|
return (uint8) get8(s);
|
|
}
|
|
|
|
static void skip(stbi *s, int n)
|
|
{
|
|
#ifndef STBI_NO_STDIO
|
|
if (s->img_file)
|
|
fseek(s->img_file, n, SEEK_CUR);
|
|
else
|
|
#endif
|
|
s->img_buffer += n;
|
|
}
|
|
|
|
static int get16(stbi *s)
|
|
{
|
|
int z = get8(s);
|
|
return (z << 8) + get8(s);
|
|
}
|
|
|
|
static uint32 get32(stbi *s)
|
|
{
|
|
uint32 z = get16(s);
|
|
return (z << 16) + get16(s);
|
|
}
|
|
|
|
static int get16le(stbi *s)
|
|
{
|
|
int z = get8(s);
|
|
return z + (get8(s) << 8);
|
|
}
|
|
|
|
static uint32 get32le(stbi *s)
|
|
{
|
|
uint32 z = get16le(s);
|
|
return z + (get16le(s) << 16);
|
|
}
|
|
|
|
static void getn(stbi *s, stbi_uc *buffer, int n)
|
|
{
|
|
#ifndef STBI_NO_STDIO
|
|
if (s->img_file) {
|
|
fread(buffer, 1, n, s->img_file);
|
|
return;
|
|
}
|
|
#endif
|
|
memcpy(buffer, s->img_buffer, n);
|
|
s->img_buffer += n;
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// 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 uint8 compute_y(int r, int g, int b)
|
|
{
|
|
return (uint8) (((r*77) + (g*150) + (29*b)) >> 8);
|
|
}
|
|
|
|
static unsigned char *convert_format(unsigned char *data, int img_n, int req_comp, uint x, uint y)
|
|
{
|
|
int i,j;
|
|
unsigned char *good;
|
|
|
|
if (req_comp == img_n) return data;
|
|
assert(req_comp >= 1 && req_comp <= 4);
|
|
|
|
good = (unsigned char *) malloc(req_comp * x * y);
|
|
if (good == NULL) {
|
|
free(data);
|
|
return epuc("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]=compute_y(src[0],src[1],src[2]); break;
|
|
CASE(3,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = 255; break;
|
|
CASE(4,1) dest[0]=compute_y(src[0],src[1],src[2]); break;
|
|
CASE(4,2) dest[0]=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: assert(0);
|
|
}
|
|
#undef CASE
|
|
}
|
|
|
|
free(data);
|
|
return good;
|
|
}
|
|
|
|
#ifndef STBI_NO_HDR
|
|
static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp)
|
|
{
|
|
int i,k,n;
|
|
float *output = (float *) malloc(x * y * comp * sizeof(float));
|
|
if (output == NULL) { free(data); return epf("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, l2h_gamma) * l2h_scale;
|
|
}
|
|
if (k < comp) output[i*comp + k] = data[i*comp+k]/255.0f;
|
|
}
|
|
free(data);
|
|
return output;
|
|
}
|
|
|
|
#define float2int(x) ((int) (x))
|
|
static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp)
|
|
{
|
|
int i,k,n;
|
|
stbi_uc *output = (stbi_uc *) malloc(x * y * comp);
|
|
if (output == NULL) { free(data); return epuc("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]*h2l_scale_i, h2l_gamma_i) * 255 + 0.5f;
|
|
if (z < 0) z = 0;
|
|
if (z > 255) z = 255;
|
|
output[i*comp + k] = 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] = float2int(z);
|
|
}
|
|
}
|
|
free(data);
|
|
return output;
|
|
}
|
|
#endif
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// "baseline" JPEG/JFIF decoder (not actually fully baseline implementation)
|
|
//
|
|
// simple implementation
|
|
// - channel subsampling of at most 2 in each dimension
|
|
// - 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
|
|
// - uses a lot of intermediate memory, could cache poorly
|
|
// - load http://nothings.org/remote/anemones.jpg 3 times on 2.8Ghz P4
|
|
// stb_jpeg: 1.34 seconds (MSVC6, default release build)
|
|
// stb_jpeg: 1.06 seconds (MSVC6, processor = Pentium Pro)
|
|
// IJL11.dll: 1.08 seconds (compiled by intel)
|
|
// IJG 1998: 0.98 seconds (MSVC6, makefile provided by IJG)
|
|
// IJG 1998: 0.95 seconds (MSVC6, makefile + proc=PPro)
|
|
|
|
// huffman decoding acceleration
|
|
#define FAST_BITS 9 // larger handles more cases; smaller stomps less cache
|
|
|
|
typedef struct
|
|
{
|
|
uint8 fast[1 << FAST_BITS];
|
|
// weirdly, repacking this into AoS is a 10% speed loss, instead of a win
|
|
uint16 code[256];
|
|
uint8 values[256];
|
|
uint8 size[257];
|
|
unsigned int maxcode[18];
|
|
int delta[17]; // old 'firstsymbol' - old 'firstcode'
|
|
} huffman;
|
|
|
|
typedef struct
|
|
{
|
|
#if STBI_SIMD
|
|
unsigned short dequant2[4][64];
|
|
#endif
|
|
stbi s;
|
|
huffman huff_dc[4];
|
|
huffman huff_ac[4];
|
|
uint8 dequant[4][64];
|
|
|
|
// 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;
|
|
uint8 *data;
|
|
void *raw_data;
|
|
uint8 *linebuf;
|
|
} img_comp[4];
|
|
|
|
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 scan_n, order[4];
|
|
int restart_interval, todo;
|
|
} jpeg;
|
|
|
|
static int build_huffman(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++] = (uint8) (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++] = (uint16) (code++);
|
|
if (code-1 >= (1 << j)) return e("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] = (uint8) i;
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static void grow_buffer_unsafe(jpeg *j)
|
|
{
|
|
do {
|
|
int b = j->nomore ? 0 : get8(&j->s);
|
|
if (b == 0xff) {
|
|
int c = get8(&j->s);
|
|
if (c != 0) {
|
|
j->marker = (unsigned char) c;
|
|
j->nomore = 1;
|
|
return;
|
|
}
|
|
}
|
|
j->code_buffer = (j->code_buffer << 8) | b;
|
|
j->code_bits += 8;
|
|
} while (j->code_bits <= 24);
|
|
}
|
|
|
|
// (1 << n) - 1
|
|
static uint32 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
|
|
__forceinline static int decode(jpeg *j, huffman *h)
|
|
{
|
|
unsigned int temp;
|
|
int c,k;
|
|
|
|
if (j->code_bits < 16) 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 >> (j->code_bits - FAST_BITS)) & ((1 << FAST_BITS)-1);
|
|
k = h->fast[c];
|
|
if (k < 255) {
|
|
if (h->size[k] > j->code_bits)
|
|
return -1;
|
|
j->code_bits -= h->size[k];
|
|
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.
|
|
if (j->code_bits < 16)
|
|
temp = (j->code_buffer << (16 - j->code_bits)) & 0xffff;
|
|
else
|
|
temp = (j->code_buffer >> (j->code_bits - 16)) & 0xffff;
|
|
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 >> (j->code_bits - k)) & bmask[k]) + h->delta[k];
|
|
assert((((j->code_buffer) >> (j->code_bits - h->size[c])) & bmask[h->size[c]]) == h->code[c]);
|
|
|
|
// convert the id to a symbol
|
|
j->code_bits -= k;
|
|
return h->values[c];
|
|
}
|
|
|
|
// combined JPEG 'receive' and JPEG 'extend', since baseline
|
|
// always extends everything it receives.
|
|
__forceinline static int extend_receive(jpeg *j, int n)
|
|
{
|
|
unsigned int m = 1 << (n-1);
|
|
unsigned int k;
|
|
if (j->code_bits < n) grow_buffer_unsafe(j);
|
|
k = (j->code_buffer >> (j->code_bits - n)) & bmask[n];
|
|
j->code_bits -= n;
|
|
// the following test is probably a random branch that won't
|
|
// predict well. I tried to table accelerate it but failed.
|
|
// maybe it's compiling as a conditional move?
|
|
if (k < m)
|
|
return (-1 << n) + k + 1;
|
|
else
|
|
return k;
|
|
}
|
|
|
|
// 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 uint8 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 decode_block(jpeg *j, short data[64], huffman *hdc, huffman *hac, int b)
|
|
{
|
|
int diff,dc,k;
|
|
int t = decode(j, hdc);
|
|
if (t < 0) return e("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 ? extend_receive(j, t) : 0;
|
|
dc = j->img_comp[b].dc_pred + diff;
|
|
j->img_comp[b].dc_pred = dc;
|
|
data[0] = (short) dc;
|
|
|
|
// decode AC components, see JPEG spec
|
|
k = 1;
|
|
do {
|
|
int r,s;
|
|
int rs = decode(j, hac);
|
|
if (rs < 0) return e("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
|
|
data[dezigzag[k++]] = (short) extend_receive(j,s);
|
|
}
|
|
} while (k < 64);
|
|
return 1;
|
|
}
|
|
|
|
// take a -128..127 value and clamp it and convert to 0..255
|
|
__forceinline static uint8 clamp(int x)
|
|
{
|
|
x += 128;
|
|
// 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 (uint8) x;
|
|
}
|
|
|
|
#define f2f(x) (int) (((x) * 4096 + 0.5))
|
|
#define fsh(x) ((x) << 12)
|
|
|
|
// derived from jidctint -- DCT_ISLOW
|
|
#define 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) * f2f(0.5411961f); \
|
|
t2 = p1 + p3*f2f(-1.847759065f); \
|
|
t3 = p1 + p2*f2f( 0.765366865f); \
|
|
p2 = s0; \
|
|
p3 = s4; \
|
|
t0 = fsh(p2+p3); \
|
|
t1 = 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)*f2f( 1.175875602f); \
|
|
t0 = t0*f2f( 0.298631336f); \
|
|
t1 = t1*f2f( 2.053119869f); \
|
|
t2 = t2*f2f( 3.072711026f); \
|
|
t3 = t3*f2f( 1.501321110f); \
|
|
p1 = p5 + p1*f2f(-0.899976223f); \
|
|
p2 = p5 + p2*f2f(-2.562915447f); \
|
|
p3 = p3*f2f(-1.961570560f); \
|
|
p4 = p4*f2f(-0.390180644f); \
|
|
t3 += p1+p4; \
|
|
t2 += p2+p3; \
|
|
t1 += p2+p4; \
|
|
t0 += p1+p3;
|
|
|
|
#if !STBI_SIMD
|
|
// .344 seconds on 3*anemones.jpg
|
|
static void idct_block(uint8 *out, int out_stride, short data[64], uint8 *dequantize)
|
|
{
|
|
int i,val[64],*v=val;
|
|
uint8 *o,*dq = dequantize;
|
|
short *d = data;
|
|
|
|
// columns
|
|
for (i=0; i < 8; ++i,++d,++dq, ++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] * dq[0] << 2;
|
|
v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm;
|
|
} else {
|
|
IDCT_1D(d[ 0]*dq[ 0],d[ 8]*dq[ 8],d[16]*dq[16],d[24]*dq[24],
|
|
d[32]*dq[32],d[40]*dq[40],d[48]*dq[48],d[56]*dq[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
|
|
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.
|
|
x0 += 65536; x1 += 65536; x2 += 65536; x3 += 65536;
|
|
o[0] = clamp((x0+t3) >> 17);
|
|
o[7] = clamp((x0-t3) >> 17);
|
|
o[1] = clamp((x1+t2) >> 17);
|
|
o[6] = clamp((x1-t2) >> 17);
|
|
o[2] = clamp((x2+t1) >> 17);
|
|
o[5] = clamp((x2-t1) >> 17);
|
|
o[3] = clamp((x3+t0) >> 17);
|
|
o[4] = clamp((x3-t0) >> 17);
|
|
}
|
|
}
|
|
#else
|
|
static void idct_block(uint8 *out, int out_stride, short data[64], unsigned short *dequantize)
|
|
{
|
|
int i,val[64],*v=val;
|
|
uint8 *o;
|
|
unsigned short *dq = dequantize;
|
|
short *d = data;
|
|
|
|
// columns
|
|
for (i=0; i < 8; ++i,++d,++dq, ++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] * dq[0] << 2;
|
|
v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm;
|
|
} else {
|
|
IDCT_1D(d[ 0]*dq[ 0],d[ 8]*dq[ 8],d[16]*dq[16],d[24]*dq[24],
|
|
d[32]*dq[32],d[40]*dq[40],d[48]*dq[48],d[56]*dq[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
|
|
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.
|
|
x0 += 65536; x1 += 65536; x2 += 65536; x3 += 65536;
|
|
o[0] = clamp((x0+t3) >> 17);
|
|
o[7] = clamp((x0-t3) >> 17);
|
|
o[1] = clamp((x1+t2) >> 17);
|
|
o[6] = clamp((x1-t2) >> 17);
|
|
o[2] = clamp((x2+t1) >> 17);
|
|
o[5] = clamp((x2-t1) >> 17);
|
|
o[3] = clamp((x3+t0) >> 17);
|
|
o[4] = clamp((x3-t0) >> 17);
|
|
}
|
|
}
|
|
static stbi_idct_8x8 stbi_idct_installed = idct_block;
|
|
|
|
extern void stbi_install_idct(stbi_idct_8x8 func)
|
|
{
|
|
stbi_idct_installed = func;
|
|
}
|
|
#endif
|
|
|
|
#define 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 uint8 get_marker(jpeg *j)
|
|
{
|
|
uint8 x;
|
|
if (j->marker != MARKER_none) { x = j->marker; j->marker = MARKER_none; return x; }
|
|
x = get8u(&j->s);
|
|
if (x != 0xff) return MARKER_none;
|
|
while (x == 0xff)
|
|
x = get8u(&j->s);
|
|
return x;
|
|
}
|
|
|
|
// in each scan, we'll have scan_n components, and the order
|
|
// of the components is specified by order[]
|
|
#define RESTART(x) ((x) >= 0xd0 && (x) <= 0xd7)
|
|
|
|
// after a restart interval, reset the entropy decoder and
|
|
// the dc prediction
|
|
static void reset(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 = MARKER_none;
|
|
j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff;
|
|
// 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 parse_entropy_coded_data(jpeg *z)
|
|
{
|
|
reset(z);
|
|
if (z->scan_n == 1) {
|
|
int i,j;
|
|
#if STBI_SIMD
|
|
__declspec(align(16))
|
|
#endif
|
|
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) {
|
|
if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0;
|
|
#if STBI_SIMD
|
|
stbi_idct_installed(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data, z->dequant2[z->img_comp[n].tq]);
|
|
#else
|
|
idct_block(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data, z->dequant[z->img_comp[n].tq]);
|
|
#endif
|
|
// every data block is an MCU, so countdown the restart interval
|
|
if (--z->todo <= 0) {
|
|
if (z->code_bits < 24) grow_buffer_unsafe(z);
|
|
// if it's NOT a restart, then just bail, so we get corrupt data
|
|
// rather than no data
|
|
if (!RESTART(z->marker)) return 1;
|
|
reset(z);
|
|
}
|
|
}
|
|
}
|
|
} else { // interleaved!
|
|
int i,j,k,x,y;
|
|
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;
|
|
if (!decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+z->img_comp[n].ha, n)) return 0;
|
|
#if STBI_SIMD
|
|
stbi_idct_installed(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data, z->dequant2[z->img_comp[n].tq]);
|
|
#else
|
|
idct_block(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data, z->dequant[z->img_comp[n].tq]);
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
// 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) grow_buffer_unsafe(z);
|
|
// if it's NOT a restart, then just bail, so we get corrupt data
|
|
// rather than no data
|
|
if (!RESTART(z->marker)) return 1;
|
|
reset(z);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int process_marker(jpeg *z, int m)
|
|
{
|
|
int L;
|
|
switch (m) {
|
|
case MARKER_none: // no marker found
|
|
return e("expected marker","Corrupt JPEG");
|
|
|
|
case 0xC2: // SOF - progressive
|
|
return e("progressive jpeg","JPEG format not supported (progressive)");
|
|
|
|
case 0xDD: // DRI - specify restart interval
|
|
if (get16(&z->s) != 4) return e("bad DRI len","Corrupt JPEG");
|
|
z->restart_interval = get16(&z->s);
|
|
return 1;
|
|
|
|
case 0xDB: // DQT - define quantization table
|
|
L = get16(&z->s)-2;
|
|
while (L > 0) {
|
|
int q = get8(&z->s);
|
|
int p = q >> 4;
|
|
int t = q & 15,i;
|
|
if (p != 0) return e("bad DQT type","Corrupt JPEG");
|
|
if (t > 3) return e("bad DQT table","Corrupt JPEG");
|
|
for (i=0; i < 64; ++i)
|
|
z->dequant[t][dezigzag[i]] = get8u(&z->s);
|
|
#if STBI_SIMD
|
|
for (i=0; i < 64; ++i)
|
|
z->dequant2[t][i] = z->dequant[t][i];
|
|
#endif
|
|
L -= 65;
|
|
}
|
|
return L==0;
|
|
|
|
case 0xC4: // DHT - define huffman table
|
|
L = get16(&z->s)-2;
|
|
while (L > 0) {
|
|
uint8 *v;
|
|
int sizes[16],i,m=0;
|
|
int q = get8(&z->s);
|
|
int tc = q >> 4;
|
|
int th = q & 15;
|
|
if (tc > 1 || th > 3) return e("bad DHT header","Corrupt JPEG");
|
|
for (i=0; i < 16; ++i) {
|
|
sizes[i] = get8(&z->s);
|
|
m += sizes[i];
|
|
}
|
|
L -= 17;
|
|
if (tc == 0) {
|
|
if (!build_huffman(z->huff_dc+th, sizes)) return 0;
|
|
v = z->huff_dc[th].values;
|
|
} else {
|
|
if (!build_huffman(z->huff_ac+th, sizes)) return 0;
|
|
v = z->huff_ac[th].values;
|
|
}
|
|
for (i=0; i < m; ++i)
|
|
v[i] = get8u(&z->s);
|
|
L -= m;
|
|
}
|
|
return L==0;
|
|
}
|
|
// check for comment block or APP blocks
|
|
if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) {
|
|
skip(&z->s, get16(&z->s)-2);
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
// after we see SOS
|
|
static int process_scan_header(jpeg *z)
|
|
{
|
|
int i;
|
|
int Ls = get16(&z->s);
|
|
z->scan_n = get8(&z->s);
|
|
if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int) z->s.img_n) return e("bad SOS component count","Corrupt JPEG");
|
|
if (Ls != 6+2*z->scan_n) return e("bad SOS len","Corrupt JPEG");
|
|
for (i=0; i < z->scan_n; ++i) {
|
|
int id = get8(&z->s), which;
|
|
int q = 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;
|
|
z->img_comp[which].hd = q >> 4; if (z->img_comp[which].hd > 3) return e("bad DC huff","Corrupt JPEG");
|
|
z->img_comp[which].ha = q & 15; if (z->img_comp[which].ha > 3) return e("bad AC huff","Corrupt JPEG");
|
|
z->order[i] = which;
|
|
}
|
|
if (get8(&z->s) != 0) return e("bad SOS","Corrupt JPEG");
|
|
get8(&z->s); // should be 63, but might be 0
|
|
if (get8(&z->s) != 0) return e("bad SOS","Corrupt JPEG");
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int process_frame_header(jpeg *z, int scan)
|
|
{
|
|
stbi *s = &z->s;
|
|
int Lf,p,i,q, h_max=1,v_max=1,c;
|
|
Lf = get16(s); if (Lf < 11) return e("bad SOF len","Corrupt JPEG"); // JPEG
|
|
p = get8(s); if (p != 8) return e("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline
|
|
s->img_y = get16(s); if (s->img_y == 0) return e("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG
|
|
s->img_x = get16(s); if (s->img_x == 0) return e("0 width","Corrupt JPEG"); // JPEG requires
|
|
c = get8(s);
|
|
if (c != 3 && c != 1) return e("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 e("bad SOF len","Corrupt JPEG");
|
|
|
|
for (i=0; i < s->img_n; ++i) {
|
|
z->img_comp[i].id = 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!
|
|
return e("bad component ID","Corrupt JPEG");
|
|
q = get8(s);
|
|
z->img_comp[i].h = (q >> 4); if (!z->img_comp[i].h || z->img_comp[i].h > 4) return e("bad H","Corrupt JPEG");
|
|
z->img_comp[i].v = q & 15; if (!z->img_comp[i].v || z->img_comp[i].v > 4) return e("bad V","Corrupt JPEG");
|
|
z->img_comp[i].tq = get8(s); if (z->img_comp[i].tq > 3) return e("bad TQ","Corrupt JPEG");
|
|
}
|
|
|
|
if (scan != SCAN_load) return 1;
|
|
|
|
if ((1 << 30) / s->img_x / s->img_n < s->img_y) return e("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 = 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) {
|
|
free(z->img_comp[i].raw_data);
|
|
z->img_comp[i].data = NULL;
|
|
}
|
|
return e("outofmem", "Out of memory");
|
|
}
|
|
// align blocks for installable-idct using mmx/sse
|
|
z->img_comp[i].data = (uint8*) (((size_t) z->img_comp[i].raw_data + 15) & ~15);
|
|
z->img_comp[i].linebuf = NULL;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
// use comparisons since in some cases we handle more than one case (e.g. SOF)
|
|
#define DNL(x) ((x) == 0xdc)
|
|
#define SOI(x) ((x) == 0xd8)
|
|
#define EOI(x) ((x) == 0xd9)
|
|
#define SOF(x) ((x) == 0xc0 || (x) == 0xc1)
|
|
#define SOS(x) ((x) == 0xda)
|
|
|
|
static int decode_jpeg_header(jpeg *z, int scan)
|
|
{
|
|
int m;
|
|
z->marker = MARKER_none; // initialize cached marker to empty
|
|
m = get_marker(z);
|
|
if (!SOI(m)) return e("no SOI","Corrupt JPEG");
|
|
if (scan == SCAN_type) return 1;
|
|
m = get_marker(z);
|
|
while (!SOF(m)) {
|
|
if (!process_marker(z,m)) return 0;
|
|
m = get_marker(z);
|
|
while (m == MARKER_none) {
|
|
// some files have extra padding after their blocks, so ok, we'll scan
|
|
if (at_eof(&z->s)) return e("no SOF", "Corrupt JPEG");
|
|
m = get_marker(z);
|
|
}
|
|
}
|
|
if (!process_frame_header(z, scan)) return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int decode_jpeg_image(jpeg *j)
|
|
{
|
|
int m;
|
|
j->restart_interval = 0;
|
|
if (!decode_jpeg_header(j, SCAN_load)) return 0;
|
|
m = get_marker(j);
|
|
while (!EOI(m)) {
|
|
if (SOS(m)) {
|
|
if (!process_scan_header(j)) return 0;
|
|
if (!parse_entropy_coded_data(j)) return 0;
|
|
} else {
|
|
if (!process_marker(j, m)) return 0;
|
|
}
|
|
m = get_marker(j);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// static jfif-centered resampling (across block boundaries)
|
|
|
|
typedef uint8 *(*resample_row_func)(uint8 *out, uint8 *in0, uint8 *in1,
|
|
int w, int hs);
|
|
|
|
#define div4(x) ((uint8) ((x) >> 2))
|
|
|
|
static uint8 *resample_row_1(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs)
|
|
{
|
|
return in_near;
|
|
}
|
|
|
|
static uint8* resample_row_v_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs)
|
|
{
|
|
// need to generate two samples vertically for every one in input
|
|
int i;
|
|
for (i=0; i < w; ++i)
|
|
out[i] = div4(3*in_near[i] + in_far[i] + 2);
|
|
return out;
|
|
}
|
|
|
|
static uint8* resample_row_h_2(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs)
|
|
{
|
|
// need to generate two samples horizontally for every one in input
|
|
int i;
|
|
uint8 *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] = div4(input[0]*3 + input[1] + 2);
|
|
for (i=1; i < w-1; ++i) {
|
|
int n = 3*input[i]+2;
|
|
out[i*2+0] = div4(n+input[i-1]);
|
|
out[i*2+1] = div4(n+input[i+1]);
|
|
}
|
|
out[i*2+0] = div4(input[w-2]*3 + input[w-1] + 2);
|
|
out[i*2+1] = input[w-1];
|
|
return out;
|
|
}
|
|
|
|
#define div16(x) ((uint8) ((x) >> 4))
|
|
|
|
static uint8 *resample_row_hv_2(uint8 *out, uint8 *in_near, uint8 *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] = div4(3*in_near[0] + in_far[0] + 2);
|
|
return out;
|
|
}
|
|
|
|
t1 = 3*in_near[0] + in_far[0];
|
|
out[0] = div4(t1+2);
|
|
for (i=1; i < w; ++i) {
|
|
t0 = t1;
|
|
t1 = 3*in_near[i]+in_far[i];
|
|
out[i*2-1] = div16(3*t0 + t1 + 8);
|
|
out[i*2 ] = div16(3*t1 + t0 + 8);
|
|
}
|
|
out[w*2-1] = div4(t1+2);
|
|
return out;
|
|
}
|
|
|
|
static uint8 *resample_row_generic(uint8 *out, uint8 *in_near, uint8 *in_far, int w, int hs)
|
|
{
|
|
// resample with nearest-neighbor
|
|
int i,j;
|
|
for (i=0; i < w; ++i)
|
|
for (j=0; j < hs; ++j)
|
|
out[i*hs+j] = in_near[i];
|
|
return out;
|
|
}
|
|
|
|
#define float2fixed(x) ((int) ((x) * 65536 + 0.5))
|
|
|
|
// 0.38 seconds on 3*anemones.jpg (0.25 with processor = Pro)
|
|
// VC6 without processor=Pro is generating multiple LEAs per multiply!
|
|
static void YCbCr_to_RGB_row(uint8 *out, const uint8 *y, const uint8 *pcb, const uint8 *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] = (uint8)r;
|
|
out[1] = (uint8)g;
|
|
out[2] = (uint8)b;
|
|
out[3] = 255;
|
|
out += step;
|
|
}
|
|
}
|
|
|
|
#if STBI_SIMD
|
|
static stbi_YCbCr_to_RGB_run stbi_YCbCr_installed = YCbCr_to_RGB_row;
|
|
|
|
void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func)
|
|
{
|
|
stbi_YCbCr_installed = func;
|
|
}
|
|
#endif
|
|
|
|
|
|
// clean up the temporary component buffers
|
|
static void cleanup_jpeg(jpeg *j)
|
|
{
|
|
int i;
|
|
for (i=0; i < j->s.img_n; ++i) {
|
|
if (j->img_comp[i].data) {
|
|
free(j->img_comp[i].raw_data);
|
|
j->img_comp[i].data = NULL;
|
|
}
|
|
if (j->img_comp[i].linebuf) {
|
|
free(j->img_comp[i].linebuf);
|
|
j->img_comp[i].linebuf = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
resample_row_func resample;
|
|
uint8 *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 uint8 *load_jpeg_image(jpeg *z, int *out_x, int *out_y, int *comp, int req_comp)
|
|
{
|
|
int n, decode_n;
|
|
// validate req_comp
|
|
if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error");
|
|
z->s.img_n = 0;
|
|
|
|
// load a jpeg image from whichever source
|
|
if (!decode_jpeg_image(z)) { 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;
|
|
uint i,j;
|
|
uint8 *output;
|
|
uint8 *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 = (uint8 *) malloc(z->s.img_x + 3);
|
|
if (!z->img_comp[k].linebuf) { cleanup_jpeg(z); return epuc("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 = resample_row_v_2;
|
|
else if (r->hs == 2 && r->vs == 1) r->resample = resample_row_h_2;
|
|
else if (r->hs == 2 && r->vs == 2) r->resample = resample_row_hv_2;
|
|
else r->resample = resample_row_generic;
|
|
}
|
|
|
|
// can't error after this so, this is safe
|
|
output = (uint8 *) malloc(n * z->s.img_x * z->s.img_y + 1);
|
|
if (!output) { cleanup_jpeg(z); return epuc("outofmem", "Out of memory"); }
|
|
|
|
// now go ahead and resample
|
|
for (j=0; j < z->s.img_y; ++j) {
|
|
uint8 *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) {
|
|
uint8 *y = coutput[0];
|
|
if (z->s.img_n == 3) {
|
|
#if STBI_SIMD
|
|
stbi_YCbCr_installed(out, y, coutput[1], coutput[2], z->s.img_x, n);
|
|
#else
|
|
YCbCr_to_RGB_row(out, y, coutput[1], coutput[2], z->s.img_x, n);
|
|
#endif
|
|
} 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 {
|
|
uint8 *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;
|
|
}
|
|
}
|
|
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;
|
|
}
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
unsigned char *stbi_jpeg_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
jpeg j;
|
|
start_file(&j.s, f);
|
|
return load_jpeg_image(&j, x,y,comp,req_comp);
|
|
}
|
|
|
|
unsigned char *stbi_jpeg_load(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char *data;
|
|
FILE *f = fopen(filename, "rb");
|
|
if (!f) return NULL;
|
|
data = stbi_jpeg_load_from_file(f,x,y,comp,req_comp);
|
|
fclose(f);
|
|
return data;
|
|
}
|
|
#endif
|
|
|
|
unsigned char *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
jpeg j;
|
|
start_mem(&j.s, buffer,len);
|
|
return load_jpeg_image(&j, x,y,comp,req_comp);
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_jpeg_test_file(FILE *f)
|
|
{
|
|
int n,r;
|
|
jpeg j;
|
|
n = ftell(f);
|
|
start_file(&j.s, f);
|
|
r = decode_jpeg_header(&j, SCAN_type);
|
|
fseek(f,n,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
int stbi_jpeg_test_memory(stbi_uc const *buffer, int len)
|
|
{
|
|
jpeg j;
|
|
start_mem(&j.s, buffer,len);
|
|
return decode_jpeg_header(&j, SCAN_type);
|
|
}
|
|
|
|
// @TODO:
|
|
#ifndef STBI_NO_STDIO
|
|
extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp);
|
|
extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp);
|
|
#endif
|
|
extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
|
|
|
|
// 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
|
|
|
|
// fast-way is faster to check than jpeg huffman, but slow way is slower
|
|
#define ZFAST_BITS 9 // accelerate all cases in default tables
|
|
#define ZFAST_MASK ((1 << ZFAST_BITS) - 1)
|
|
|
|
// zlib-style huffman encoding
|
|
// (jpegs packs from left, zlib from right, so can't share code)
|
|
typedef struct
|
|
{
|
|
uint16 fast[1 << ZFAST_BITS];
|
|
uint16 firstcode[16];
|
|
int maxcode[17];
|
|
uint16 firstsymbol[16];
|
|
uint8 size[288];
|
|
uint16 value[288];
|
|
} zhuffman;
|
|
|
|
__forceinline static int 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;
|
|
}
|
|
|
|
__forceinline static int bit_reverse(int v, int bits)
|
|
{
|
|
assert(bits <= 16);
|
|
// to bit reverse n bits, reverse 16 and shift
|
|
// e.g. 11 bits, bit reverse and shift away 5
|
|
return bitreverse16(v) >> (16-bits);
|
|
}
|
|
|
|
static int zbuild_huffman(zhuffman *z, uint8 *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, 255, sizeof(z->fast));
|
|
for (i=0; i < num; ++i)
|
|
++sizes[sizelist[i]];
|
|
sizes[0] = 0;
|
|
for (i=1; i < 16; ++i)
|
|
assert(sizes[i] <= (1 << i));
|
|
code = 0;
|
|
for (i=1; i < 16; ++i) {
|
|
next_code[i] = code;
|
|
z->firstcode[i] = (uint16) code;
|
|
z->firstsymbol[i] = (uint16) k;
|
|
code = (code + sizes[i]);
|
|
if (sizes[i])
|
|
if (code-1 >= (1 << i)) return e("bad codelengths","Corrupt JPEG");
|
|
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];
|
|
z->size[c] = (uint8)s;
|
|
z->value[c] = (uint16)i;
|
|
if (s <= ZFAST_BITS) {
|
|
int k = bit_reverse(next_code[s],s);
|
|
while (k < (1 << ZFAST_BITS)) {
|
|
z->fast[k] = (uint16) c;
|
|
k += (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
|
|
{
|
|
uint8 *zbuffer, *zbuffer_end;
|
|
int num_bits;
|
|
uint32 code_buffer;
|
|
|
|
char *zout;
|
|
char *zout_start;
|
|
char *zout_end;
|
|
int z_expandable;
|
|
|
|
zhuffman z_length, z_distance;
|
|
} zbuf;
|
|
|
|
__forceinline static int zget8(zbuf *z)
|
|
{
|
|
if (z->zbuffer >= z->zbuffer_end) return 0;
|
|
return *z->zbuffer++;
|
|
}
|
|
|
|
static void fill_bits(zbuf *z)
|
|
{
|
|
do {
|
|
assert(z->code_buffer < (1U << z->num_bits));
|
|
z->code_buffer |= zget8(z) << z->num_bits;
|
|
z->num_bits += 8;
|
|
} while (z->num_bits <= 24);
|
|
}
|
|
|
|
__forceinline static unsigned int zreceive(zbuf *z, int n)
|
|
{
|
|
unsigned int k;
|
|
if (z->num_bits < n) fill_bits(z);
|
|
k = z->code_buffer & ((1 << n) - 1);
|
|
z->code_buffer >>= n;
|
|
z->num_bits -= n;
|
|
return k;
|
|
}
|
|
|
|
__forceinline static int zhuffman_decode(zbuf *a, zhuffman *z)
|
|
{
|
|
int b,s,k;
|
|
if (a->num_bits < 16) fill_bits(a);
|
|
b = z->fast[a->code_buffer & ZFAST_MASK];
|
|
if (b < 0xffff) {
|
|
s = z->size[b];
|
|
a->code_buffer >>= s;
|
|
a->num_bits -= s;
|
|
return z->value[b];
|
|
}
|
|
|
|
// not resolved by fast table, so compute it the slow way
|
|
// use jpeg approach, which requires MSbits at top
|
|
k = bit_reverse(a->code_buffer, 16);
|
|
for (s=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];
|
|
assert(z->size[b] == s);
|
|
a->code_buffer >>= s;
|
|
a->num_bits -= s;
|
|
return z->value[b];
|
|
}
|
|
|
|
static int expand(zbuf *z, int n) // need to make room for n bytes
|
|
{
|
|
char *q;
|
|
int cur, limit;
|
|
if (!z->z_expandable) return e("output buffer limit","Corrupt PNG");
|
|
cur = (int) (z->zout - z->zout_start);
|
|
limit = (int) (z->zout_end - z->zout_start);
|
|
while (cur + n > limit)
|
|
limit *= 2;
|
|
q = (char *) realloc(z->zout_start, limit);
|
|
if (q == NULL) return e("outofmem", "Out of memory");
|
|
z->zout_start = q;
|
|
z->zout = q + cur;
|
|
z->zout_end = q + limit;
|
|
return 1;
|
|
}
|
|
|
|
static int length_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 length_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 dist_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 dist_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 parse_huffman_block(zbuf *a)
|
|
{
|
|
for(;;) {
|
|
int z = zhuffman_decode(a, &a->z_length);
|
|
if (z < 256) {
|
|
if (z < 0) return e("bad huffman code","Corrupt PNG"); // error in huffman codes
|
|
if (a->zout >= a->zout_end) if (!expand(a, 1)) return 0;
|
|
*a->zout++ = (char) z;
|
|
} else {
|
|
uint8 *p;
|
|
int len,dist;
|
|
if (z == 256) return 1;
|
|
z -= 257;
|
|
len = length_base[z];
|
|
if (length_extra[z]) len += zreceive(a, length_extra[z]);
|
|
z = zhuffman_decode(a, &a->z_distance);
|
|
if (z < 0) return e("bad huffman code","Corrupt PNG");
|
|
dist = dist_base[z];
|
|
if (dist_extra[z]) dist += zreceive(a, dist_extra[z]);
|
|
if (a->zout - a->zout_start < dist) return e("bad dist","Corrupt PNG");
|
|
if (a->zout + len > a->zout_end) if (!expand(a, len)) return 0;
|
|
p = (uint8 *) (a->zout - dist);
|
|
while (len--)
|
|
*a->zout++ = *p++;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int compute_huffman_codes(zbuf *a)
|
|
{
|
|
static uint8 length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 };
|
|
zhuffman z_codelength;
|
|
uint8 lencodes[286+32+137];//padding for maximum single op
|
|
uint8 codelength_sizes[19];
|
|
int i,n;
|
|
|
|
int hlit = zreceive(a,5) + 257;
|
|
int hdist = zreceive(a,5) + 1;
|
|
int hclen = zreceive(a,4) + 4;
|
|
|
|
memset(codelength_sizes, 0, sizeof(codelength_sizes));
|
|
for (i=0; i < hclen; ++i) {
|
|
int s = zreceive(a,3);
|
|
codelength_sizes[length_dezigzag[i]] = (uint8) s;
|
|
}
|
|
if (!zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0;
|
|
|
|
n = 0;
|
|
while (n < hlit + hdist) {
|
|
int c = zhuffman_decode(a, &z_codelength);
|
|
assert(c >= 0 && c < 19);
|
|
if (c < 16)
|
|
lencodes[n++] = (uint8) c;
|
|
else if (c == 16) {
|
|
c = zreceive(a,2)+3;
|
|
memset(lencodes+n, lencodes[n-1], c);
|
|
n += c;
|
|
} else if (c == 17) {
|
|
c = zreceive(a,3)+3;
|
|
memset(lencodes+n, 0, c);
|
|
n += c;
|
|
} else {
|
|
assert(c == 18);
|
|
c = zreceive(a,7)+11;
|
|
memset(lencodes+n, 0, c);
|
|
n += c;
|
|
}
|
|
}
|
|
if (n != hlit+hdist) return e("bad codelengths","Corrupt PNG");
|
|
if (!zbuild_huffman(&a->z_length, lencodes, hlit)) return 0;
|
|
if (!zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int parse_uncompressed_block(zbuf *a)
|
|
{
|
|
uint8 header[4];
|
|
int len,nlen,k;
|
|
if (a->num_bits & 7)
|
|
zreceive(a, a->num_bits & 7); // discard
|
|
// drain the bit-packed data into header
|
|
k = 0;
|
|
while (a->num_bits > 0) {
|
|
header[k++] = (uint8) (a->code_buffer & 255); // wtf this warns?
|
|
a->code_buffer >>= 8;
|
|
a->num_bits -= 8;
|
|
}
|
|
assert(a->num_bits == 0);
|
|
// now fill header the normal way
|
|
while (k < 4)
|
|
header[k++] = (uint8) zget8(a);
|
|
len = header[1] * 256 + header[0];
|
|
nlen = header[3] * 256 + header[2];
|
|
if (nlen != (len ^ 0xffff)) return e("zlib corrupt","Corrupt PNG");
|
|
if (a->zbuffer + len > a->zbuffer_end) return e("read past buffer","Corrupt PNG");
|
|
if (a->zout + len > a->zout_end)
|
|
if (!expand(a, len)) return 0;
|
|
memcpy(a->zout, a->zbuffer, len);
|
|
a->zbuffer += len;
|
|
a->zout += len;
|
|
return 1;
|
|
}
|
|
|
|
static int parse_zlib_header(zbuf *a)
|
|
{
|
|
int cmf = zget8(a);
|
|
int cm = cmf & 15;
|
|
/* int cinfo = cmf >> 4; */
|
|
int flg = zget8(a);
|
|
if ((cmf*256+flg) % 31 != 0) return e("bad zlib header","Corrupt PNG"); // zlib spec
|
|
if (flg & 32) return e("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png
|
|
if (cm != 8) return e("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 uint8 default_length[288], default_distance[32];
|
|
static void init_defaults(void)
|
|
{
|
|
int i; // use <= to match clearly with spec
|
|
for (i=0; i <= 143; ++i) default_length[i] = 8;
|
|
for ( ; i <= 255; ++i) default_length[i] = 9;
|
|
for ( ; i <= 279; ++i) default_length[i] = 7;
|
|
for ( ; i <= 287; ++i) default_length[i] = 8;
|
|
|
|
for (i=0; i <= 31; ++i) default_distance[i] = 5;
|
|
}
|
|
|
|
int stbi_png_partial; // a quick hack to only allow decoding some of a PNG... I should implement real streaming support instead
|
|
static int parse_zlib(zbuf *a, int parse_header)
|
|
{
|
|
int final, type;
|
|
if (parse_header)
|
|
if (!parse_zlib_header(a)) return 0;
|
|
a->num_bits = 0;
|
|
a->code_buffer = 0;
|
|
do {
|
|
final = zreceive(a,1);
|
|
type = zreceive(a,2);
|
|
if (type == 0) {
|
|
if (!parse_uncompressed_block(a)) return 0;
|
|
} else if (type == 3) {
|
|
return 0;
|
|
} else {
|
|
if (type == 1) {
|
|
// use fixed code lengths
|
|
if (!default_distance[31]) init_defaults();
|
|
if (!zbuild_huffman(&a->z_length , default_length , 288)) return 0;
|
|
if (!zbuild_huffman(&a->z_distance, default_distance, 32)) return 0;
|
|
} else {
|
|
if (!compute_huffman_codes(a)) return 0;
|
|
}
|
|
if (!parse_huffman_block(a)) return 0;
|
|
}
|
|
if (stbi_png_partial && a->zout - a->zout_start > 65536)
|
|
break;
|
|
} while (!final);
|
|
return 1;
|
|
}
|
|
|
|
static int do_zlib(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 parse_zlib(a, parse_header);
|
|
}
|
|
|
|
char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen)
|
|
{
|
|
zbuf a;
|
|
char *p = (char *) malloc(initial_size);
|
|
if (p == NULL) return NULL;
|
|
a.zbuffer = (uint8 *) buffer;
|
|
a.zbuffer_end = (uint8 *) buffer + len;
|
|
if (do_zlib(&a, p, initial_size, 1, 1)) {
|
|
if (outlen) *outlen = (int) (a.zout - a.zout_start);
|
|
return a.zout_start;
|
|
} else {
|
|
free(a.zout_start);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen)
|
|
{
|
|
return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen);
|
|
}
|
|
|
|
int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen)
|
|
{
|
|
zbuf a;
|
|
a.zbuffer = (uint8 *) ibuffer;
|
|
a.zbuffer_end = (uint8 *) ibuffer + ilen;
|
|
if (do_zlib(&a, obuffer, olen, 0, 1))
|
|
return (int) (a.zout - a.zout_start);
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen)
|
|
{
|
|
zbuf a;
|
|
char *p = (char *) malloc(16384);
|
|
if (p == NULL) return NULL;
|
|
a.zbuffer = (uint8 *) buffer;
|
|
a.zbuffer_end = (uint8 *) buffer+len;
|
|
if (do_zlib(&a, p, 16384, 1, 0)) {
|
|
if (outlen) *outlen = (int) (a.zout - a.zout_start);
|
|
return a.zout_start;
|
|
} else {
|
|
free(a.zout_start);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen)
|
|
{
|
|
zbuf a;
|
|
a.zbuffer = (uint8 *) ibuffer;
|
|
a.zbuffer_end = (uint8 *) ibuffer + ilen;
|
|
if (do_zlib(&a, obuffer, olen, 0, 0))
|
|
return (int) (a.zout - a.zout_start);
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
// 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
|
|
|
|
|
|
typedef struct
|
|
{
|
|
uint32 length;
|
|
uint32 type;
|
|
} chunk;
|
|
|
|
#define PNG_TYPE(a,b,c,d) (((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
|
|
|
|
static chunk get_chunk_header(stbi *s)
|
|
{
|
|
chunk c;
|
|
c.length = get32(s);
|
|
c.type = get32(s);
|
|
return c;
|
|
}
|
|
|
|
static int check_png_header(stbi *s)
|
|
{
|
|
static uint8 png_sig[8] = { 137,80,78,71,13,10,26,10 };
|
|
int i;
|
|
for (i=0; i < 8; ++i)
|
|
if (get8(s) != png_sig[i]) return e("bad png sig","Not a PNG");
|
|
return 1;
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
stbi s;
|
|
uint8 *idata, *expanded, *out;
|
|
} png;
|
|
|
|
|
|
enum {
|
|
F_none=0, F_sub=1, F_up=2, F_avg=3, F_paeth=4,
|
|
F_avg_first, F_paeth_first,
|
|
};
|
|
|
|
static uint8 first_row_filter[5] =
|
|
{
|
|
F_none, F_sub, F_none, F_avg_first, F_paeth_first
|
|
};
|
|
|
|
static int 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;
|
|
}
|
|
|
|
// create the png data from post-deflated data
|
|
static int create_png_image_raw(png *a, uint8 *raw, uint32 raw_len, int out_n, uint32 x, uint32 y)
|
|
{
|
|
stbi *s = &a->s;
|
|
uint32 i,j,stride = x*out_n;
|
|
int k;
|
|
int img_n = s->img_n; // copy it into a local for later
|
|
assert(out_n == s->img_n || out_n == s->img_n+1);
|
|
if (stbi_png_partial) y = 1;
|
|
a->out = (uint8 *) malloc(x * y * out_n);
|
|
if (!a->out) return e("outofmem", "Out of memory");
|
|
if (!stbi_png_partial) {
|
|
if (s->img_x == x && s->img_y == y)
|
|
if (raw_len != (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG");
|
|
else // interlaced:
|
|
if (raw_len < (img_n * x + 1) * y) return e("not enough pixels","Corrupt PNG");
|
|
}
|
|
for (j=0; j < y; ++j) {
|
|
uint8 *cur = a->out + stride*j;
|
|
uint8 *prior = cur - stride;
|
|
int filter = *raw++;
|
|
if (filter > 4) return e("invalid filter","Corrupt PNG");
|
|
// if first row, use special filter that doesn't sample previous row
|
|
if (j == 0) filter = first_row_filter[filter];
|
|
// handle first pixel explicitly
|
|
for (k=0; k < img_n; ++k) {
|
|
switch(filter) {
|
|
case F_none : cur[k] = raw[k]; break;
|
|
case F_sub : cur[k] = raw[k]; break;
|
|
case F_up : cur[k] = raw[k] + prior[k]; break;
|
|
case F_avg : cur[k] = raw[k] + (prior[k]>>1); break;
|
|
case F_paeth : cur[k] = (uint8) (raw[k] + paeth(0,prior[k],0)); break;
|
|
case F_avg_first : cur[k] = raw[k]; break;
|
|
case F_paeth_first: cur[k] = raw[k]; break;
|
|
}
|
|
}
|
|
if (img_n != out_n) cur[img_n] = 255;
|
|
raw += img_n;
|
|
cur += out_n;
|
|
prior += out_n;
|
|
// this is a little gross, so that we don't switch per-pixel or per-component
|
|
if (img_n == out_n) {
|
|
#define CASE(f) \
|
|
case f: \
|
|
for (i=x-1; i >= 1; --i, raw+=img_n,cur+=img_n,prior+=img_n) \
|
|
for (k=0; k < img_n; ++k)
|
|
switch(filter) {
|
|
CASE(F_none) cur[k] = raw[k]; break;
|
|
CASE(F_sub) cur[k] = raw[k] + cur[k-img_n]; break;
|
|
CASE(F_up) cur[k] = raw[k] + prior[k]; break;
|
|
CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-img_n])>>1); break;
|
|
CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],prior[k],prior[k-img_n])); break;
|
|
CASE(F_avg_first) cur[k] = raw[k] + (cur[k-img_n] >> 1); break;
|
|
CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-img_n],0,0)); break;
|
|
}
|
|
#undef CASE
|
|
} else {
|
|
assert(img_n+1 == out_n);
|
|
#define CASE(f) \
|
|
case f: \
|
|
for (i=x-1; i >= 1; --i, cur[img_n]=255,raw+=img_n,cur+=out_n,prior+=out_n) \
|
|
for (k=0; k < img_n; ++k)
|
|
switch(filter) {
|
|
CASE(F_none) cur[k] = raw[k]; break;
|
|
CASE(F_sub) cur[k] = raw[k] + cur[k-out_n]; break;
|
|
CASE(F_up) cur[k] = raw[k] + prior[k]; break;
|
|
CASE(F_avg) cur[k] = raw[k] + ((prior[k] + cur[k-out_n])>>1); break;
|
|
CASE(F_paeth) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],prior[k],prior[k-out_n])); break;
|
|
CASE(F_avg_first) cur[k] = raw[k] + (cur[k-out_n] >> 1); break;
|
|
CASE(F_paeth_first) cur[k] = (uint8) (raw[k] + paeth(cur[k-out_n],0,0)); break;
|
|
}
|
|
#undef CASE
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static int create_png_image(png *a, uint8 *raw, uint32 raw_len, int out_n, int interlaced)
|
|
{
|
|
uint8 *final;
|
|
int p;
|
|
int save;
|
|
if (!interlaced)
|
|
return create_png_image_raw(a, raw, raw_len, out_n, a->s.img_x, a->s.img_y);
|
|
save = stbi_png_partial;
|
|
stbi_png_partial = 0;
|
|
|
|
// de-interlacing
|
|
final = (uint8 *) 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) {
|
|
if (!create_png_image_raw(a, raw, raw_len, out_n, x, y)) {
|
|
free(final);
|
|
return 0;
|
|
}
|
|
for (j=0; j < y; ++j)
|
|
for (i=0; i < x; ++i)
|
|
memcpy(final + (j*yspc[p]+yorig[p])*a->s.img_x*out_n + (i*xspc[p]+xorig[p])*out_n,
|
|
a->out + (j*x+i)*out_n, out_n);
|
|
free(a->out);
|
|
raw += (x*out_n+1)*y;
|
|
raw_len -= (x*out_n+1)*y;
|
|
}
|
|
}
|
|
a->out = final;
|
|
|
|
stbi_png_partial = save;
|
|
return 1;
|
|
}
|
|
|
|
static int compute_transparency(png *z, uint8 tc[3], int out_n)
|
|
{
|
|
stbi *s = &z->s;
|
|
uint32 i, pixel_count = s->img_x * s->img_y;
|
|
uint8 *p = z->out;
|
|
|
|
// compute color-based transparency, assuming we've
|
|
// already got 255 as the alpha value in the output
|
|
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 expand_palette(png *a, uint8 *palette, int len, int pal_img_n)
|
|
{
|
|
uint32 i, pixel_count = a->s.img_x * a->s.img_y;
|
|
uint8 *p, *temp_out, *orig = a->out;
|
|
|
|
p = (uint8 *) malloc(pixel_count * pal_img_n);
|
|
if (p == NULL) return e("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;
|
|
}
|
|
}
|
|
free(a->out);
|
|
a->out = temp_out;
|
|
return 1;
|
|
}
|
|
|
|
static int parse_png_file(png *z, int scan, int req_comp)
|
|
{
|
|
uint8 palette[1024], pal_img_n=0;
|
|
uint8 has_trans=0, tc[3];
|
|
uint32 ioff=0, idata_limit=0, i, pal_len=0;
|
|
int first=1,k,interlace=0;
|
|
stbi *s = &z->s;
|
|
|
|
if (!check_png_header(s)) return 0;
|
|
|
|
if (scan == SCAN_type) return 1;
|
|
|
|
for(;;first=0) {
|
|
chunk c = get_chunk_header(s);
|
|
if (first && c.type != PNG_TYPE('I','H','D','R'))
|
|
return e("first not IHDR","Corrupt PNG");
|
|
switch (c.type) {
|
|
case PNG_TYPE('I','H','D','R'): {
|
|
int depth,color,comp,filter;
|
|
if (!first) return e("multiple IHDR","Corrupt PNG");
|
|
if (c.length != 13) return e("bad IHDR len","Corrupt PNG");
|
|
s->img_x = get32(s); if (s->img_x > (1 << 24)) return e("too large","Very large image (corrupt?)");
|
|
s->img_y = get32(s); if (s->img_y > (1 << 24)) return e("too large","Very large image (corrupt?)");
|
|
depth = get8(s); if (depth != 8) return e("8bit only","PNG not supported: 8-bit only");
|
|
color = get8(s); if (color > 6) return e("bad ctype","Corrupt PNG");
|
|
if (color == 3) pal_img_n = 3; else if (color & 1) return e("bad ctype","Corrupt PNG");
|
|
comp = get8(s); if (comp) return e("bad comp method","Corrupt PNG");
|
|
filter= get8(s); if (filter) return e("bad filter method","Corrupt PNG");
|
|
interlace = get8(s); if (interlace>1) return e("bad interlace method","Corrupt PNG");
|
|
if (!s->img_x || !s->img_y) return e("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 e("too large", "Image too large to decode");
|
|
if (scan == 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 e("too large","Corrupt PNG");
|
|
// if SCAN_header, have to scan to see if we have a tRNS
|
|
}
|
|
break;
|
|
}
|
|
|
|
case PNG_TYPE('P','L','T','E'): {
|
|
if (c.length > 256*3) return e("invalid PLTE","Corrupt PNG");
|
|
pal_len = c.length / 3;
|
|
if (pal_len * 3 != c.length) return e("invalid PLTE","Corrupt PNG");
|
|
for (i=0; i < pal_len; ++i) {
|
|
palette[i*4+0] = get8u(s);
|
|
palette[i*4+1] = get8u(s);
|
|
palette[i*4+2] = get8u(s);
|
|
palette[i*4+3] = 255;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case PNG_TYPE('t','R','N','S'): {
|
|
if (z->idata) return e("tRNS after IDAT","Corrupt PNG");
|
|
if (pal_img_n) {
|
|
if (scan == SCAN_header) { s->img_n = 4; return 1; }
|
|
if (pal_len == 0) return e("tRNS before PLTE","Corrupt PNG");
|
|
if (c.length > pal_len) return e("bad tRNS len","Corrupt PNG");
|
|
pal_img_n = 4;
|
|
for (i=0; i < c.length; ++i)
|
|
palette[i*4+3] = get8u(s);
|
|
} else {
|
|
if (!(s->img_n & 1)) return e("tRNS with alpha","Corrupt PNG");
|
|
if (c.length != (uint32) s->img_n*2) return e("bad tRNS len","Corrupt PNG");
|
|
has_trans = 1;
|
|
for (k=0; k < s->img_n; ++k)
|
|
tc[k] = (uint8) get16(s); // non 8-bit images will be larger
|
|
}
|
|
break;
|
|
}
|
|
|
|
case PNG_TYPE('I','D','A','T'): {
|
|
if (pal_img_n && !pal_len) return e("no PLTE","Corrupt PNG");
|
|
if (scan == SCAN_header) { s->img_n = pal_img_n; return 1; }
|
|
if (ioff + c.length > idata_limit) {
|
|
uint8 *p;
|
|
if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096;
|
|
while (ioff + c.length > idata_limit)
|
|
idata_limit *= 2;
|
|
p = (uint8 *) realloc(z->idata, idata_limit); if (p == NULL) return e("outofmem", "Out of memory");
|
|
z->idata = p;
|
|
}
|
|
#ifndef STBI_NO_STDIO
|
|
if (s->img_file)
|
|
{
|
|
if (fread(z->idata+ioff,1,c.length,s->img_file) != c.length) return e("outofdata","Corrupt PNG");
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
memcpy(z->idata+ioff, s->img_buffer, c.length);
|
|
s->img_buffer += c.length;
|
|
}
|
|
ioff += c.length;
|
|
break;
|
|
}
|
|
|
|
case PNG_TYPE('I','E','N','D'): {
|
|
uint32 raw_len;
|
|
if (scan != SCAN_load) return 1;
|
|
if (z->idata == NULL) return e("no IDAT","Corrupt PNG");
|
|
z->expanded = (uint8 *) stbi_zlib_decode_malloc((char *) z->idata, ioff, (int *) &raw_len);
|
|
if (z->expanded == NULL) return 0; // zlib should set error
|
|
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 (!create_png_image(z, z->expanded, raw_len, s->img_out_n, interlace)) return 0;
|
|
if (has_trans)
|
|
if (!compute_transparency(z, tc, s->img_out_n)) return 0;
|
|
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 (!expand_palette(z, palette, pal_len, s->img_out_n))
|
|
return 0;
|
|
}
|
|
free(z->expanded); z->expanded = NULL;
|
|
return 1;
|
|
}
|
|
|
|
default:
|
|
// if critical, fail
|
|
if ((c.type & (1 << 29)) == 0) {
|
|
#ifndef STBI_NO_FAILURE_STRINGS
|
|
// not threadsafe
|
|
static char invalid_chunk[] = "XXXX chunk not known";
|
|
invalid_chunk[0] = (uint8) (c.type >> 24);
|
|
invalid_chunk[1] = (uint8) (c.type >> 16);
|
|
invalid_chunk[2] = (uint8) (c.type >> 8);
|
|
invalid_chunk[3] = (uint8) (c.type >> 0);
|
|
#endif
|
|
return e(invalid_chunk, "PNG not supported: unknown chunk type");
|
|
}
|
|
skip(s, c.length);
|
|
break;
|
|
}
|
|
// end of chunk, read and skip CRC
|
|
get32(s);
|
|
}
|
|
}
|
|
|
|
static unsigned char *do_png(png *p, int *x, int *y, int *n, int req_comp)
|
|
{
|
|
unsigned char *result=NULL;
|
|
p->expanded = NULL;
|
|
p->idata = NULL;
|
|
p->out = NULL;
|
|
if (req_comp < 0 || req_comp > 4) return epuc("bad req_comp", "Internal error");
|
|
if (parse_png_file(p, SCAN_load, req_comp)) {
|
|
result = p->out;
|
|
p->out = NULL;
|
|
if (req_comp && req_comp != p->s.img_out_n) {
|
|
result = 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;
|
|
}
|
|
free(p->out); p->out = NULL;
|
|
free(p->expanded); p->expanded = NULL;
|
|
free(p->idata); p->idata = NULL;
|
|
|
|
return result;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
unsigned char *stbi_png_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
png p;
|
|
start_file(&p.s, f);
|
|
return do_png(&p, x,y,comp,req_comp);
|
|
}
|
|
|
|
unsigned char *stbi_png_load(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
unsigned char *data;
|
|
FILE *f = fopen(filename, "rb");
|
|
if (!f) return NULL;
|
|
data = stbi_png_load_from_file(f,x,y,comp,req_comp);
|
|
fclose(f);
|
|
return data;
|
|
}
|
|
#endif
|
|
|
|
unsigned char *stbi_png_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
png p;
|
|
start_mem(&p.s, buffer,len);
|
|
return do_png(&p, x,y,comp,req_comp);
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_png_test_file(FILE *f)
|
|
{
|
|
png p;
|
|
int n,r;
|
|
n = ftell(f);
|
|
start_file(&p.s, f);
|
|
r = parse_png_file(&p, SCAN_type,STBI_default);
|
|
fseek(f,n,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
int stbi_png_test_memory(stbi_uc const *buffer, int len)
|
|
{
|
|
png p;
|
|
start_mem(&p.s, buffer, len);
|
|
return parse_png_file(&p, SCAN_type,STBI_default);
|
|
}
|
|
|
|
// TODO: load header from png
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_png_info (char const *filename, int *x, int *y, int *comp)
|
|
{
|
|
png p;
|
|
FILE *f = fopen(filename, "rb");
|
|
if (!f) return 0;
|
|
start_file(&p.s, f);
|
|
if (parse_png_file(&p, SCAN_header, 0)) {
|
|
if(x) *x = p.s.img_x;
|
|
if(y) *y = p.s.img_y;
|
|
if (comp) *comp = p.s.img_n;
|
|
fclose(f);
|
|
return 1;
|
|
}
|
|
fclose(f);
|
|
return 0;
|
|
}
|
|
|
|
extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp);
|
|
#endif
|
|
extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp);
|
|
|
|
// Microsoft/Windows BMP image
|
|
|
|
static int bmp_test(stbi *s)
|
|
{
|
|
int sz;
|
|
if (get8(s) != 'B') return 0;
|
|
if (get8(s) != 'M') return 0;
|
|
get32le(s); // discard filesize
|
|
get16le(s); // discard reserved
|
|
get16le(s); // discard reserved
|
|
get32le(s); // discard data offset
|
|
sz = get32le(s);
|
|
if (sz == 12 || sz == 40 || sz == 56 || sz == 108) return 1;
|
|
return 0;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_bmp_test_file (FILE *f)
|
|
{
|
|
stbi s;
|
|
int r,n = ftell(f);
|
|
start_file(&s,f);
|
|
r = bmp_test(&s);
|
|
fseek(f,n,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
int stbi_bmp_test_memory (stbi_uc const *buffer, int len)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return bmp_test(&s);
|
|
}
|
|
|
|
// returns 0..31 for the highest set bit
|
|
static int 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 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 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;
|
|
}
|
|
|
|
static stbi_uc *bmp_load(stbi *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
uint8 *out;
|
|
unsigned int mr=0,mg=0,mb=0,ma=0, fake_a=0;
|
|
stbi_uc pal[256][4];
|
|
int psize=0,i,j,compress=0,width;
|
|
int bpp, flip_vertically, pad, target, offset, hsz;
|
|
if (get8(s) != 'B' || get8(s) != 'M') return epuc("not BMP", "Corrupt BMP");
|
|
get32le(s); // discard filesize
|
|
get16le(s); // discard reserved
|
|
get16le(s); // discard reserved
|
|
offset = get32le(s);
|
|
hsz = get32le(s);
|
|
if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108) return epuc("unknown BMP", "BMP type not supported: unknown");
|
|
failure_reason = "bad BMP";
|
|
if (hsz == 12) {
|
|
s->img_x = get16le(s);
|
|
s->img_y = get16le(s);
|
|
} else {
|
|
s->img_x = get32le(s);
|
|
s->img_y = get32le(s);
|
|
}
|
|
if (get16le(s) != 1) return 0;
|
|
bpp = get16le(s);
|
|
if (bpp == 1) return epuc("monochrome", "BMP type not supported: 1-bit");
|
|
flip_vertically = ((int) s->img_y) > 0;
|
|
s->img_y = abs((int) s->img_y);
|
|
if (hsz == 12) {
|
|
if (bpp < 24)
|
|
psize = (offset - 14 - 24) / 3;
|
|
} else {
|
|
compress = get32le(s);
|
|
if (compress == 1 || compress == 2) return epuc("BMP RLE", "BMP type not supported: RLE");
|
|
get32le(s); // discard sizeof
|
|
get32le(s); // discard hres
|
|
get32le(s); // discard vres
|
|
get32le(s); // discard colorsused
|
|
get32le(s); // discard max important
|
|
if (hsz == 40 || hsz == 56) {
|
|
if (hsz == 56) {
|
|
get32le(s);
|
|
get32le(s);
|
|
get32le(s);
|
|
get32le(s);
|
|
}
|
|
if (bpp == 16 || bpp == 32) {
|
|
mr = mg = mb = 0;
|
|
if (compress == 0) {
|
|
if (bpp == 32) {
|
|
mr = 0xff << 16;
|
|
mg = 0xff << 8;
|
|
mb = 0xff << 0;
|
|
ma = 0xff << 24;
|
|
fake_a = 1; // @TODO: check for cases like alpha value is all 0 and switch it to 255
|
|
} else {
|
|
mr = 31 << 10;
|
|
mg = 31 << 5;
|
|
mb = 31 << 0;
|
|
}
|
|
} else if (compress == 3) {
|
|
mr = get32le(s);
|
|
mg = get32le(s);
|
|
mb = get32le(s);
|
|
// not documented, but generated by photoshop and handled by mspaint
|
|
if (mr == mg && mg == mb) {
|
|
// ?!?!?
|
|
return NULL;
|
|
}
|
|
} else
|
|
return NULL;
|
|
}
|
|
} else {
|
|
assert(hsz == 108);
|
|
mr = get32le(s);
|
|
mg = get32le(s);
|
|
mb = get32le(s);
|
|
ma = get32le(s);
|
|
get32le(s); // discard color space
|
|
for (i=0; i < 12; ++i)
|
|
get32le(s); // discard color space parameters
|
|
}
|
|
if (bpp < 16)
|
|
psize = (offset - 14 - 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 *) malloc(target * s->img_x * s->img_y);
|
|
if (!out) return epuc("outofmem", "Out of memory");
|
|
if (bpp < 16) {
|
|
int z=0;
|
|
if (psize == 0 || psize > 256) { free(out); return epuc("invalid", "Corrupt BMP"); }
|
|
for (i=0; i < psize; ++i) {
|
|
pal[i][2] = get8(s);
|
|
pal[i][1] = get8(s);
|
|
pal[i][0] = get8(s);
|
|
if (hsz != 12) get8(s);
|
|
pal[i][3] = 255;
|
|
}
|
|
skip(s, offset - 14 - hsz - psize * (hsz == 12 ? 3 : 4));
|
|
if (bpp == 4) width = (s->img_x + 1) >> 1;
|
|
else if (bpp == 8) width = s->img_x;
|
|
else { free(out); return epuc("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=get8(s),v2=0;
|
|
if (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 = (bpp == 8) ? get8(s) : v2;
|
|
out[z++] = pal[v][0];
|
|
out[z++] = pal[v][1];
|
|
out[z++] = pal[v][2];
|
|
if (target == 4) out[z++] = 255;
|
|
}
|
|
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;
|
|
skip(s, offset - 14 - hsz);
|
|
if (bpp == 24) width = 3 * s->img_x;
|
|
else if (bpp == 16) width = 2*s->img_x;
|
|
else /* bpp = 32 and pad = 0 */ width=0;
|
|
pad = (-width) & 3;
|
|
if (bpp == 24) {
|
|
easy = 1;
|
|
} else if (bpp == 32) {
|
|
if (mb == 0xff && mg == 0xff00 && mr == 0xff000000 && ma == 0xff000000)
|
|
easy = 2;
|
|
}
|
|
if (!easy) {
|
|
if (!mr || !mg || !mb) return epuc("bad masks", "Corrupt BMP");
|
|
// right shift amt to put high bit in position #7
|
|
rshift = high_bit(mr)-7; rcount = bitcount(mr);
|
|
gshift = high_bit(mg)-7; gcount = bitcount(mr);
|
|
bshift = high_bit(mb)-7; bcount = bitcount(mr);
|
|
ashift = high_bit(ma)-7; acount = bitcount(mr);
|
|
}
|
|
for (j=0; j < (int) s->img_y; ++j) {
|
|
if (easy) {
|
|
for (i=0; i < (int) s->img_x; ++i) {
|
|
int a;
|
|
out[z+2] = get8(s);
|
|
out[z+1] = get8(s);
|
|
out[z+0] = get8(s);
|
|
z += 3;
|
|
a = (easy == 2 ? get8(s) : 255);
|
|
if (target == 4) out[z++] = a;
|
|
}
|
|
} else {
|
|
for (i=0; i < (int) s->img_x; ++i) {
|
|
uint32 v = (bpp == 16 ? get16le(s) : get32le(s));
|
|
int a;
|
|
out[z++] = shiftsigned(v & mr, rshift, rcount);
|
|
out[z++] = shiftsigned(v & mg, gshift, gcount);
|
|
out[z++] = shiftsigned(v & mb, bshift, bcount);
|
|
a = (ma ? shiftsigned(v & ma, ashift, acount) : 255);
|
|
if (target == 4) out[z++] = a;
|
|
}
|
|
}
|
|
skip(s, pad);
|
|
}
|
|
}
|
|
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 = convert_format(out, target, req_comp, s->img_x, s->img_y);
|
|
if (out == NULL) return out; // convert_format frees input on failure
|
|
}
|
|
|
|
*x = s->img_x;
|
|
*y = s->img_y;
|
|
if (comp) *comp = target;
|
|
return out;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *data;
|
|
FILE *f = fopen(filename, "rb");
|
|
if (!f) return NULL;
|
|
data = stbi_bmp_load_from_file(f, x,y,comp,req_comp);
|
|
fclose(f);
|
|
return data;
|
|
}
|
|
|
|
stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_file(&s, f);
|
|
return bmp_load(&s, x,y,comp,req_comp);
|
|
}
|
|
#endif
|
|
|
|
stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return bmp_load(&s, x,y,comp,req_comp);
|
|
}
|
|
|
|
// Targa Truevision - TGA
|
|
// by Jonathan Dummer
|
|
|
|
static int tga_test(stbi *s)
|
|
{
|
|
int sz;
|
|
get8u(s); // discard Offset
|
|
sz = get8u(s); // color type
|
|
if( sz > 1 ) return 0; // only RGB or indexed allowed
|
|
sz = get8u(s); // image type
|
|
if( (sz != 1) && (sz != 2) && (sz != 3) && (sz != 9) && (sz != 10) && (sz != 11) ) return 0; // only RGB or grey allowed, +/- RLE
|
|
get16(s); // discard palette start
|
|
get16(s); // discard palette length
|
|
get8(s); // discard bits per palette color entry
|
|
get16(s); // discard x origin
|
|
get16(s); // discard y origin
|
|
if( get16(s) < 1 ) return 0; // test width
|
|
if( get16(s) < 1 ) return 0; // test height
|
|
sz = get8(s); // bits per pixel
|
|
if( (sz != 8) && (sz != 16) && (sz != 24) && (sz != 32) ) return 0; // only RGB or RGBA or grey allowed
|
|
return 1; // seems to have passed everything
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_tga_test_file (FILE *f)
|
|
{
|
|
stbi s;
|
|
int r,n = ftell(f);
|
|
start_file(&s, f);
|
|
r = tga_test(&s);
|
|
fseek(f,n,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
int stbi_tga_test_memory (stbi_uc const *buffer, int len)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return tga_test(&s);
|
|
}
|
|
|
|
static stbi_uc *tga_load(stbi *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
// read in the TGA header stuff
|
|
int tga_offset = get8u(s);
|
|
int tga_indexed = get8u(s);
|
|
int tga_image_type = get8u(s);
|
|
int tga_is_RLE = 0;
|
|
int tga_palette_start = get16le(s);
|
|
int tga_palette_len = get16le(s);
|
|
int tga_palette_bits = get8u(s);
|
|
int tga_x_origin = get16le(s);
|
|
int tga_y_origin = get16le(s);
|
|
int tga_width = get16le(s);
|
|
int tga_height = get16le(s);
|
|
int tga_bits_per_pixel = get8u(s);
|
|
int tga_inverted = get8u(s);
|
|
// image data
|
|
unsigned char *tga_data;
|
|
unsigned char *tga_palette = NULL;
|
|
int i, j;
|
|
unsigned char raw_data[4];
|
|
unsigned char trans_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;
|
|
}
|
|
/* int tga_alpha_bits = tga_inverted & 15; */
|
|
tga_inverted = 1 - ((tga_inverted >> 5) & 1);
|
|
|
|
// error check
|
|
if( //(tga_indexed) ||
|
|
(tga_width < 1) || (tga_height < 1) ||
|
|
(tga_image_type < 1) || (tga_image_type > 3) ||
|
|
((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16) &&
|
|
(tga_bits_per_pixel != 24) && (tga_bits_per_pixel != 32))
|
|
)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
// If I'm paletted, then I'll use the number of bits from the palette
|
|
if( tga_indexed )
|
|
{
|
|
tga_bits_per_pixel = tga_palette_bits;
|
|
}
|
|
|
|
// tga info
|
|
*x = tga_width;
|
|
*y = tga_height;
|
|
if( (req_comp < 1) || (req_comp > 4) )
|
|
{
|
|
// just use whatever the file was
|
|
req_comp = tga_bits_per_pixel / 8;
|
|
*comp = req_comp;
|
|
} else
|
|
{
|
|
// force a new number of components
|
|
*comp = tga_bits_per_pixel/8;
|
|
}
|
|
tga_data = (unsigned char*)malloc( tga_width * tga_height * req_comp );
|
|
|
|
// skip to the data's starting position (offset usually = 0)
|
|
skip(s, tga_offset );
|
|
// do I need to load a palette?
|
|
if( tga_indexed )
|
|
{
|
|
// any data to skip? (offset usually = 0)
|
|
skip(s, tga_palette_start );
|
|
// load the palette
|
|
tga_palette = (unsigned char*)malloc( tga_palette_len * tga_palette_bits / 8 );
|
|
getn(s, tga_palette, tga_palette_len * tga_palette_bits / 8 );
|
|
}
|
|
// 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 chunk?
|
|
if( tga_is_RLE )
|
|
{
|
|
if( RLE_count == 0 )
|
|
{
|
|
// yep, get the next byte as a RLE command
|
|
int RLE_cmd = get8u(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 1 byte, then perform the lookup
|
|
int pal_idx = get8u(s);
|
|
if( pal_idx >= tga_palette_len )
|
|
{
|
|
// invalid index
|
|
pal_idx = 0;
|
|
}
|
|
pal_idx *= tga_bits_per_pixel / 8;
|
|
for( j = 0; j*8 < tga_bits_per_pixel; ++j )
|
|
{
|
|
raw_data[j] = tga_palette[pal_idx+j];
|
|
}
|
|
} else
|
|
{
|
|
// read in the data raw
|
|
for( j = 0; j*8 < tga_bits_per_pixel; ++j )
|
|
{
|
|
raw_data[j] = get8u(s);
|
|
}
|
|
}
|
|
// convert raw to the intermediate format
|
|
switch( tga_bits_per_pixel )
|
|
{
|
|
case 8:
|
|
// Luminous => RGBA
|
|
trans_data[0] = raw_data[0];
|
|
trans_data[1] = raw_data[0];
|
|
trans_data[2] = raw_data[0];
|
|
trans_data[3] = 255;
|
|
break;
|
|
case 16:
|
|
// Luminous,Alpha => RGBA
|
|
trans_data[0] = raw_data[0];
|
|
trans_data[1] = raw_data[0];
|
|
trans_data[2] = raw_data[0];
|
|
trans_data[3] = raw_data[1];
|
|
break;
|
|
case 24:
|
|
// BGR => RGBA
|
|
trans_data[0] = raw_data[2];
|
|
trans_data[1] = raw_data[1];
|
|
trans_data[2] = raw_data[0];
|
|
trans_data[3] = 255;
|
|
break;
|
|
case 32:
|
|
// BGRA => RGBA
|
|
trans_data[0] = raw_data[2];
|
|
trans_data[1] = raw_data[1];
|
|
trans_data[2] = raw_data[0];
|
|
trans_data[3] = raw_data[3];
|
|
break;
|
|
}
|
|
// clear the reading flag for the next pixel
|
|
read_next_pixel = 0;
|
|
} // end of reading a pixel
|
|
// convert to final format
|
|
switch( req_comp )
|
|
{
|
|
case 1:
|
|
// RGBA => Luminance
|
|
tga_data[i*req_comp+0] = compute_y(trans_data[0],trans_data[1],trans_data[2]);
|
|
break;
|
|
case 2:
|
|
// RGBA => Luminance,Alpha
|
|
tga_data[i*req_comp+0] = compute_y(trans_data[0],trans_data[1],trans_data[2]);
|
|
tga_data[i*req_comp+1] = trans_data[3];
|
|
break;
|
|
case 3:
|
|
// RGBA => RGB
|
|
tga_data[i*req_comp+0] = trans_data[0];
|
|
tga_data[i*req_comp+1] = trans_data[1];
|
|
tga_data[i*req_comp+2] = trans_data[2];
|
|
break;
|
|
case 4:
|
|
// RGBA => RGBA
|
|
tga_data[i*req_comp+0] = trans_data[0];
|
|
tga_data[i*req_comp+1] = trans_data[1];
|
|
tga_data[i*req_comp+2] = trans_data[2];
|
|
tga_data[i*req_comp+3] = trans_data[3];
|
|
break;
|
|
}
|
|
// 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 * req_comp;
|
|
int index2 = (tga_height - 1 - j) * tga_width * req_comp;
|
|
for( i = tga_width * req_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 )
|
|
{
|
|
free( tga_palette );
|
|
}
|
|
// 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;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *data;
|
|
FILE *f = fopen(filename, "rb");
|
|
if (!f) return NULL;
|
|
data = stbi_tga_load_from_file(f, x,y,comp,req_comp);
|
|
fclose(f);
|
|
return data;
|
|
}
|
|
|
|
stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_file(&s, f);
|
|
return tga_load(&s, x,y,comp,req_comp);
|
|
}
|
|
#endif
|
|
|
|
stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return tga_load(&s, x,y,comp,req_comp);
|
|
}
|
|
|
|
|
|
// *************************************************************************************************
|
|
// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicholas Schulz, tweaked by STB
|
|
|
|
static int psd_test(stbi *s)
|
|
{
|
|
if (get32(s) != 0x38425053) return 0; // "8BPS"
|
|
else return 1;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_psd_test_file(FILE *f)
|
|
{
|
|
stbi s;
|
|
int r,n = ftell(f);
|
|
start_file(&s, f);
|
|
r = psd_test(&s);
|
|
fseek(f,n,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
int stbi_psd_test_memory(stbi_uc const *buffer, int len)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return psd_test(&s);
|
|
}
|
|
|
|
static stbi_uc *psd_load(stbi *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
int pixelCount;
|
|
int channelCount, compression;
|
|
int channel, i, count, len;
|
|
int w,h;
|
|
uint8 *out;
|
|
|
|
// Check identifier
|
|
if (get32(s) != 0x38425053) // "8BPS"
|
|
return epuc("not PSD", "Corrupt PSD image");
|
|
|
|
// Check file type version.
|
|
if (get16(s) != 1)
|
|
return epuc("wrong version", "Unsupported version of PSD image");
|
|
|
|
// Skip 6 reserved bytes.
|
|
skip(s, 6 );
|
|
|
|
// Read the number of channels (R, G, B, A, etc).
|
|
channelCount = get16(s);
|
|
if (channelCount < 0 || channelCount > 16)
|
|
return epuc("wrong channel count", "Unsupported number of channels in PSD image");
|
|
|
|
// Read the rows and columns of the image.
|
|
h = get32(s);
|
|
w = get32(s);
|
|
|
|
// Make sure the depth is 8 bits.
|
|
if (get16(s) != 8)
|
|
return epuc("unsupported bit depth", "PSD bit depth is not 8 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 (get16(s) != 3)
|
|
return epuc("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.)
|
|
skip(s,get32(s) );
|
|
|
|
// Skip the image resources. (resolution, pen tool paths, etc)
|
|
skip(s, get32(s) );
|
|
|
|
// Skip the reserved data.
|
|
skip(s, get32(s) );
|
|
|
|
// Find out if the data is compressed.
|
|
// Known values:
|
|
// 0: no compression
|
|
// 1: RLE compressed
|
|
compression = get16(s);
|
|
if (compression > 1)
|
|
return epuc("bad compression", "PSD has an unknown compression format");
|
|
|
|
// Create the destination image.
|
|
out = (stbi_uc *) malloc(4 * w*h);
|
|
if (!out) return epuc("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.
|
|
skip(s, h * channelCount * 2 );
|
|
|
|
// Read the RLE data by channel.
|
|
for (channel = 0; channel < 4; channel++) {
|
|
uint8 *p;
|
|
|
|
p = out+channel;
|
|
if (channel >= channelCount) {
|
|
// Fill this channel with default data.
|
|
for (i = 0; i < pixelCount; i++) *p = (channel == 3 ? 255 : 0), p += 4;
|
|
} else {
|
|
// Read the RLE data.
|
|
count = 0;
|
|
while (count < pixelCount) {
|
|
len = get8(s);
|
|
if (len == 128) {
|
|
// No-op.
|
|
} else if (len < 128) {
|
|
// Copy next len+1 bytes literally.
|
|
len++;
|
|
count += len;
|
|
while (len) {
|
|
*p = get8(s);
|
|
p += 4;
|
|
len--;
|
|
}
|
|
} else if (len > 128) {
|
|
uint32 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 = 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++) {
|
|
uint8 *p;
|
|
|
|
p = out + channel;
|
|
if (channel > channelCount) {
|
|
// Fill this channel with default data.
|
|
for (i = 0; i < pixelCount; i++) *p = channel == 3 ? 255 : 0, p += 4;
|
|
} else {
|
|
// Read the data.
|
|
count = 0;
|
|
for (i = 0; i < pixelCount; i++)
|
|
*p = get8(s), p += 4;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (req_comp && req_comp != 4) {
|
|
out = convert_format(out, 4, req_comp, w, h);
|
|
if (out == NULL) return out; // convert_format frees input on failure
|
|
}
|
|
|
|
if (comp) *comp = channelCount;
|
|
*y = h;
|
|
*x = w;
|
|
|
|
return out;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
stbi_uc *stbi_psd_load(char const *filename, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi_uc *data;
|
|
FILE *f = fopen(filename, "rb");
|
|
if (!f) return NULL;
|
|
data = stbi_psd_load_from_file(f, x,y,comp,req_comp);
|
|
fclose(f);
|
|
return data;
|
|
}
|
|
|
|
stbi_uc *stbi_psd_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_file(&s, f);
|
|
return psd_load(&s, x,y,comp,req_comp);
|
|
}
|
|
#endif
|
|
|
|
stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return psd_load(&s, x,y,comp,req_comp);
|
|
}
|
|
|
|
|
|
// *************************************************************************************************
|
|
// Radiance RGBE HDR loader
|
|
// originally by Nicolas Schulz
|
|
#ifndef STBI_NO_HDR
|
|
static int hdr_test(stbi *s)
|
|
{
|
|
char *signature = "#?RADIANCE\n";
|
|
int i;
|
|
for (i=0; signature[i]; ++i)
|
|
if (get8(s) != signature[i])
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
int stbi_hdr_test_memory(stbi_uc const *buffer, int len)
|
|
{
|
|
stbi s;
|
|
start_mem(&s, buffer, len);
|
|
return hdr_test(&s);
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
int stbi_hdr_test_file(FILE *f)
|
|
{
|
|
stbi s;
|
|
int r,n = ftell(f);
|
|
start_file(&s, f);
|
|
r = hdr_test(&s);
|
|
fseek(f,n,SEEK_SET);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
#define HDR_BUFLEN 1024
|
|
static char *hdr_gettoken(stbi *z, char *buffer)
|
|
{
|
|
int len=0;
|
|
char *s = buffer, c = '\0';
|
|
|
|
c = get8(z);
|
|
|
|
while (!at_eof(z) && c != '\n') {
|
|
buffer[len++] = c;
|
|
if (len == HDR_BUFLEN-1) {
|
|
// flush to end of line
|
|
while (!at_eof(z) && get8(z) != '\n')
|
|
;
|
|
break;
|
|
}
|
|
c = get8(z);
|
|
}
|
|
|
|
buffer[len] = 0;
|
|
return buffer;
|
|
}
|
|
|
|
static void 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 *hdr_load(stbi *s, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
char buffer[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(hdr_gettoken(s,buffer), "#?RADIANCE") != 0)
|
|
return epf("not HDR", "Corrupt HDR image");
|
|
|
|
// Parse header
|
|
while(1) {
|
|
token = hdr_gettoken(s,buffer);
|
|
if (token[0] == 0) break;
|
|
if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
|
|
}
|
|
|
|
if (!valid) return epf("unsupported format", "Unsupported HDR format");
|
|
|
|
// Parse width and height
|
|
// can't use sscanf() if we're not using stdio!
|
|
token = hdr_gettoken(s,buffer);
|
|
if (strncmp(token, "-Y ", 3)) return epf("unsupported data layout", "Unsupported HDR format");
|
|
token += 3;
|
|
height = strtol(token, &token, 10);
|
|
while (*token == ' ') ++token;
|
|
if (strncmp(token, "+X ", 3)) return epf("unsupported data layout", "Unsupported HDR format");
|
|
token += 3;
|
|
width = strtol(token, NULL, 10);
|
|
|
|
*x = width;
|
|
*y = height;
|
|
|
|
*comp = 3;
|
|
if (req_comp == 0) req_comp = 3;
|
|
|
|
// Read data
|
|
hdr_data = (float *) 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:
|
|
getn(s, rgbe, 4);
|
|
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 = get8(s);
|
|
c2 = get8(s);
|
|
len = 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] = { c1,c2,len, get8(s) };
|
|
hdr_convert(hdr_data, rgbe, req_comp);
|
|
i = 1;
|
|
j = 0;
|
|
free(scanline);
|
|
goto main_decode_loop; // yes, this is fucking insane; blame the fucking insane format
|
|
}
|
|
len <<= 8;
|
|
len |= get8(s);
|
|
if (len != width) { free(hdr_data); free(scanline); return epf("invalid decoded scanline length", "corrupt HDR"); }
|
|
if (scanline == NULL) scanline = (stbi_uc *) malloc(width * 4);
|
|
|
|
for (k = 0; k < 4; ++k) {
|
|
i = 0;
|
|
while (i < width) {
|
|
count = get8(s);
|
|
if (count > 128) {
|
|
// Run
|
|
value = 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] = get8(s);
|
|
}
|
|
}
|
|
}
|
|
for (i=0; i < width; ++i)
|
|
hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp);
|
|
}
|
|
free(scanline);
|
|
}
|
|
|
|
return hdr_data;
|
|
}
|
|
|
|
#ifndef STBI_NO_STDIO
|
|
float *stbi_hdr_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_file(&s,f);
|
|
return hdr_load(&s,x,y,comp,req_comp);
|
|
}
|
|
#endif
|
|
|
|
float *stbi_hdr_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
|
|
{
|
|
stbi s;
|
|
start_mem(&s,buffer, len);
|
|
return hdr_load(&s,x,y,comp,req_comp);
|
|
}
|
|
|
|
#endif // STBI_NO_HDR
|
|
|
|
/////////////////////// write image ///////////////////////
|
|
|
|
#ifndef STBI_NO_WRITE
|
|
|
|
static void write8(FILE *f, int x) { uint8 z = (uint8) x; fwrite(&z,1,1,f); }
|
|
|
|
static void writefv(FILE *f, char *fmt, va_list v)
|
|
{
|
|
while (*fmt) {
|
|
switch (*fmt++) {
|
|
case ' ': break;
|
|
case '1': { uint8 x = va_arg(v, int); write8(f,x); break; }
|
|
case '2': { int16 x = va_arg(v, int); write8(f,x); write8(f,x>>8); break; }
|
|
case '4': { int32 x = va_arg(v, int); write8(f,x); write8(f,x>>8); write8(f,x>>16); write8(f,x>>24); break; }
|
|
default:
|
|
assert(0);
|
|
va_end(v);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void writef(FILE *f, char *fmt, ...)
|
|
{
|
|
va_list v;
|
|
va_start(v, fmt);
|
|
writefv(f,fmt,v);
|
|
va_end(v);
|
|
}
|
|
|
|
static void write_pixels(FILE *f, int rgb_dir, int vdir, int x, int y, int comp, void *data, int write_alpha, int scanline_pad)
|
|
{
|
|
uint8 bg[3] = { 255, 0, 255}, px[3];
|
|
uint32 zero = 0;
|
|
int i,j,k, j_end;
|
|
|
|
if (vdir < 0)
|
|
j_end = -1, j = y-1;
|
|
else
|
|
j_end = y, j = 0;
|
|
|
|
for (; j != j_end; j += vdir) {
|
|
for (i=0; i < x; ++i) {
|
|
uint8 *d = (uint8 *) data + (j*x+i)*comp;
|
|
if (write_alpha < 0)
|
|
fwrite(&d[comp-1], 1, 1, f);
|
|
switch (comp) {
|
|
case 1:
|
|
case 2: writef(f, "111", d[0],d[0],d[0]);
|
|
break;
|
|
case 4:
|
|
if (!write_alpha) {
|
|
for (k=0; k < 3; ++k)
|
|
px[k] = bg[k] + ((d[k] - bg[k]) * d[3])/255;
|
|
writef(f, "111", px[1-rgb_dir],px[1],px[1+rgb_dir]);
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
case 3:
|
|
writef(f, "111", d[1-rgb_dir],d[1],d[1+rgb_dir]);
|
|
break;
|
|
}
|
|
if (write_alpha > 0)
|
|
fwrite(&d[comp-1], 1, 1, f);
|
|
}
|
|
fwrite(&zero,scanline_pad,1,f);
|
|
}
|
|
}
|
|
|
|
static int outfile(char const *filename, int rgb_dir, int vdir, int x, int y, int comp, void *data, int alpha, int pad, char *fmt, ...)
|
|
{
|
|
FILE *f = fopen(filename, "wb");
|
|
if (f) {
|
|
va_list v;
|
|
va_start(v, fmt);
|
|
writefv(f, fmt, v);
|
|
va_end(v);
|
|
write_pixels(f,rgb_dir,vdir,x,y,comp,data,alpha,pad);
|
|
fclose(f);
|
|
}
|
|
return f != NULL;
|
|
}
|
|
|
|
int stbi_write_bmp(char const *filename, int x, int y, int comp, void *data)
|
|
{
|
|
int pad = (-x*3) & 3;
|
|
return outfile(filename,-1,-1,x,y,comp,data,0,pad,
|
|
"11 4 22 4" "4 44 22 444444",
|
|
'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40, // file header
|
|
40, x,y, 1,24, 0,0,0,0,0,0); // bitmap header
|
|
}
|
|
|
|
int stbi_write_tga(char const *filename, int x, int y, int comp, void *data)
|
|
{
|
|
int has_alpha = !(comp & 1);
|
|
return outfile(filename, -1,-1, x, y, comp, data, has_alpha, 0,
|
|
"111 221 2222 11", 0,0,2, 0,0,0, 0,0,x,y, 24+8*has_alpha, 8*has_alpha);
|
|
}
|
|
|
|
// any other image formats that do interleaved rgb data?
|
|
// PNG: requires adler32,crc32 -- significant amount of code
|
|
// PSD: no, channels output separately
|
|
// TIFF: no, stripwise-interleaved... i think
|
|
|
|
#endif // STBI_NO_WRITE
|
|
|
|
#endif // STBI_HEADER_FILE_ONLY
|
|
|