1043 lines
39 KiB
C
1043 lines
39 KiB
C
/* stb_image_write - v1.13 - public domain - http://nothings.org/stb
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* writes out PNG/BMP/TGA/JPEG/HDR images to C stdio - Sean Barrett 2010-2015
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* no warranty implied; use at your own risk
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*
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* ABOUT:
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*
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* This file is a library for writing images to stdio or a callback.
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*
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* The PNG output is not optimal; it is 20-50% larger than the file
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* written by a decent optimizing implementation; though providing a
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* custom zlib compress function (see STBIW_ZLIB_COMPRESS) can
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* mitigate that. This library is designed for source code
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* compactness and simplicity, not optimal image file size or
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* run-time performance.
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*
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* USAGE:
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*
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* There are five functions, one for each image file format:
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*
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* stbi_write_png
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* stbi_write_bmp
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* stbi_write_tga
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* stbi_write_jpg
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* stbi_write_hdr
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*
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* stbi_flip_vertically_on_write
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*
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* There are also five equivalent functions that use an arbitrary
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* write function. You are expected to open/close your
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* file-equivalent before and after calling these:
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*
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* stbi_write_png_to_func
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* stbi_write_bmp_to_func
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* stbi_write_tga_to_func
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* stbi_write_hdr_to_func
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* stbi_write_jpg_to_func
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*
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* where the callback is:
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* void stbi_write_func(void *context, void *data, int size);
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*
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* You can configure it with these:
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* stbi_write_tga_with_rle
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* stbi_write_png_compression_level
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* stbi_write_force_png_filter
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*
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* Each function returns 0 on failure and non-0 on success.
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*
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* The functions create an image file defined by the parameters. The
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* image is a rectangle of pixels stored from left-to-right,
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* top-to-bottom. Each pixel contains 'comp' channels of data stored
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* interleaved with 8-bits per channel, in the following order: 1=Y,
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* 2=YA, 3=RGB, 4=RGBA. (Y is monochrome color.) The rectangle is 'w'
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* pixels wide and 'h' pixels tall. The *data pointer points to the
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* first byte of the top-left-most pixel. For PNG, "stride_in_bytes"
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* is the distance in bytes from the first byte of a row of pixels to
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* the first byte of the next row of pixels.
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*
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* PNG creates output files with the same number of components as the
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* input. The BMP format expands Y to RGB in the file format and does
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* not output alpha.
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*
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* PNG supports writing rectangles of data even when the bytes
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* storing rows of data are not consecutive in memory (e.g.
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* sub-rectangles of a larger image), by supplying the stride between
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* the beginning of adjacent rows. The other formats do not. (Thus
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* you cannot write a native-format BMP through the BMP writer, both
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* because it is in BGR order and because it may have padding at the
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* end of the line.)
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*
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* PNG allows you to set the deflate compression level by setting the
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* global variable 'stbi_write_png_compression_level' (it defaults to
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* 8).
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*
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* HDR expects linear float data. Since the format is always 32-bit
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* rgb(e) data, alpha (if provided) is discarded, and for monochrome
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* data it is replicated across all three channels.
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*
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* TGA supports RLE or non-RLE compressed data. To use
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* non-RLE-compressed data, set the global variable
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* 'stbi_write_tga_with_rle' to 0.
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*
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* JPEG does ignore alpha channels in input data; quality is between
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* 1 and 100. Higher quality looks better but results in a bigger
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* image. JPEG baseline (no JPEG progressive).
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*
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* CREDITS:
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*
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*
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* Sean Barrett - PNG/BMP/TGA
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* Baldur Karlsson - HDR
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* Jean-Sebastien Guay - TGA monochrome
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* Tim Kelsey - misc enhancements
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* Alan Hickman - TGA RLE
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* Emmanuel Julien - initial file IO callback implementation
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* Jon Olick - original jo_jpeg.cpp code
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* Daniel Gibson - integrate JPEG, allow external zlib
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* Aarni Koskela - allow choosing PNG filter
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*
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* bugfixes:
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* github:Chribba
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* Guillaume Chereau
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* github:jry2
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* github:romigrou
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* Sergio Gonzalez
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* Jonas Karlsson
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* Filip Wasil
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* Thatcher Ulrich
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* github:poppolopoppo
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* Patrick Boettcher
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* github:xeekworx
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* Cap Petschulat
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* Simon Rodriguez
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* Ivan Tikhonov
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* github:ignotion
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* Adam Schackart
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*
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* LICENSE
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*
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* Public Domain (www.unlicense.org)
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*/
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#include "dsp/core/core.h"
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#include "libc/assert.h"
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#include "libc/conv/conv.h"
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#include "libc/fmt/fmt.h"
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#include "libc/limits.h"
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#include "libc/macros.h"
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#include "libc/math.h"
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#include "libc/mem/mem.h"
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#include "libc/nexgen32e/nexgen32e.h"
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#include "libc/stdio/stdio.h"
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#include "libc/str/str.h"
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#include "third_party/stb/stb_image_write.h"
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#include "third_party/zlib/zlib.h"
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#define STBIW_UCHAR(x) (unsigned char)((x)&0xff)
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#define STBIW_REALLOC_SIZED(p, oldsz, newsz) realloc(p, newsz)
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typedef struct {
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stbi_write_func *func;
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void *context;
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} stbi__write_context;
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int stbi__flip_vertically_on_write = 0;
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int stbi_write_tga_with_rle = 1;
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void stbi_flip_vertically_on_write(int flag) {
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stbi__flip_vertically_on_write = flag;
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}
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// initialize a callback-based context
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static void stbi__start_write_callbacks(stbi__write_context *s,
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stbi_write_func *c, void *context) {
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s->func = c;
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s->context = context;
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}
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static void stbi__stdio_write(void *context, void *data, int size) {
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fwrite(data, 1, size, (FILE *)context);
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}
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static int stbi__start_write_file(stbi__write_context *s,
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const char *filename) {
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FILE *f = fopen(filename, "wb");
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stbi__start_write_callbacks(s, stbi__stdio_write, (void *)f);
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return f != NULL;
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}
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static void stbi__end_write_file(stbi__write_context *s) {
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fclose((FILE *)s->context);
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}
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typedef unsigned int stbiw_uint32;
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typedef int stb_image_write_test[sizeof(stbiw_uint32) == 4 ? 1 : -1];
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static void stbiw__writefv(stbi__write_context *s, const char *fmt, va_list v) {
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while (*fmt) {
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switch (*fmt++) {
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case ' ':
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break;
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case '1': {
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unsigned char x = STBIW_UCHAR(va_arg(v, int));
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s->func(s->context, &x, 1);
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break;
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}
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case '2': {
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int x = va_arg(v, int);
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unsigned char b[2];
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b[0] = STBIW_UCHAR(x);
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b[1] = STBIW_UCHAR(x >> 8);
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s->func(s->context, b, 2);
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break;
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}
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case '4': {
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stbiw_uint32 x = va_arg(v, int);
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unsigned char b[4];
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b[0] = STBIW_UCHAR(x);
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b[1] = STBIW_UCHAR(x >> 8);
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b[2] = STBIW_UCHAR(x >> 16);
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b[3] = STBIW_UCHAR(x >> 24);
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s->func(s->context, b, 4);
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break;
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}
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default:
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unreachable;
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}
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}
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}
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static void stbiw__writef(stbi__write_context *s, const char *fmt, ...) {
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va_list v;
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va_start(v, fmt);
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stbiw__writefv(s, fmt, v);
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va_end(v);
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}
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static void stbiw__putc(stbi__write_context *s, unsigned char c) {
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s->func(s->context, &c, 1);
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}
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static void stbiw__write3(stbi__write_context *s, unsigned char a,
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unsigned char b, unsigned char c) {
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unsigned char arr[3];
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arr[0] = a;
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arr[1] = b;
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arr[2] = c;
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s->func(s->context, arr, 3);
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}
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static void stbiw__write_pixel(stbi__write_context *s, int rgb_dir, int comp,
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int write_alpha, int expand_mono,
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unsigned char *d) {
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unsigned char bg[3] = {255, 0, 255}, px[3];
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int k;
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if (write_alpha < 0) s->func(s->context, &d[comp - 1], 1);
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switch (comp) {
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case 2: // 2 pixels = mono + alpha, alpha is written separately, so same as
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// 1-channel case
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case 1:
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if (expand_mono)
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stbiw__write3(s, d[0], d[0], d[0]); // monochrome bmp
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else
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s->func(s->context, d, 1); // monochrome TGA
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break;
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case 4:
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if (!write_alpha) {
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// composite against pink background
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for (k = 0; k < 3; ++k) px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255;
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stbiw__write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]);
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break;
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}
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/* FALLTHROUGH */
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case 3:
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stbiw__write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]);
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break;
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}
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if (write_alpha > 0) s->func(s->context, &d[comp - 1], 1);
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}
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static void stbiw__write_pixels(stbi__write_context *s, int rgb_dir, int vdir,
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int x, int y, int comp, void *data,
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int write_alpha, int scanline_pad,
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int expand_mono) {
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stbiw_uint32 zero = 0;
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int i, j, j_end;
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if (y <= 0) return;
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if (stbi__flip_vertically_on_write) vdir *= -1;
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if (vdir < 0) {
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j_end = -1;
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j = y - 1;
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} else {
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j_end = y;
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j = 0;
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}
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for (; j != j_end; j += vdir) {
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for (i = 0; i < x; ++i) {
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unsigned char *d = (unsigned char *)data + (j * x + i) * comp;
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stbiw__write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d);
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}
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s->func(s->context, &zero, scanline_pad);
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}
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}
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static int stbiw__outfile(stbi__write_context *s, int rgb_dir, int vdir, int x,
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int y, int comp, int expand_mono, void *data,
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int alpha, int pad, const char *fmt, ...) {
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if (y < 0 || x < 0) {
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return 0;
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} else {
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va_list v;
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va_start(v, fmt);
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stbiw__writefv(s, fmt, v);
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va_end(v);
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stbiw__write_pixels(s, rgb_dir, vdir, x, y, comp, data, alpha, pad,
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expand_mono);
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return 1;
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}
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}
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static int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp,
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const void *data) {
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int pad = (-x * 3) & 3;
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return stbiw__outfile(s, -1, -1, x, y, comp, 1, (void *)data, 0, pad,
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"11 4 22 4"
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"4 44 22 444444",
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'B', 'M', 14 + 40 + (x * 3 + pad) * y, 0, 0,
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14 + 40, // file header
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40, x, y, 1, 24, 0, 0, 0, 0, 0, 0); // bitmap header
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}
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int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, int y,
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int comp, const void *data) {
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stbi__write_context s;
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stbi__start_write_callbacks(&s, func, context);
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return stbi_write_bmp_core(&s, x, y, comp, data);
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}
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int stbi_write_bmp(char const *filename, int x, int y, int comp,
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const void *data) {
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stbi__write_context s;
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if (stbi__start_write_file(&s, filename)) {
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int r = stbi_write_bmp_core(&s, x, y, comp, data);
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stbi__end_write_file(&s);
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return r;
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} else
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return 0;
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}
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static int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp,
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void *data) {
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int has_alpha = (comp == 2 || comp == 4);
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int colorbytes = has_alpha ? comp - 1 : comp;
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int format =
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colorbytes < 2
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? 3
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: 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3
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if (y < 0 || x < 0) return 0;
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if (!stbi_write_tga_with_rle) {
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return stbiw__outfile(s, -1, -1, x, y, comp, 0, (void *)data, has_alpha, 0,
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"111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y,
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(colorbytes + has_alpha) * 8, has_alpha * 8);
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} else {
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int i, j, k;
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int jend, jdir;
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stbiw__writef(s, "111 221 2222 11", 0, 0, format + 8, 0, 0, 0, 0, 0, x, y,
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(colorbytes + has_alpha) * 8, has_alpha * 8);
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if (stbi__flip_vertically_on_write) {
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j = 0;
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jend = y;
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jdir = 1;
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} else {
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j = y - 1;
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jend = -1;
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jdir = -1;
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}
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for (; j != jend; j += jdir) {
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unsigned char *row = (unsigned char *)data + j * x * comp;
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int len;
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for (i = 0; i < x; i += len) {
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unsigned char *begin = row + i * comp;
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int diff = 1;
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len = 1;
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if (i < x - 1) {
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++len;
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diff = memcmp(begin, row + (i + 1) * comp, comp);
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if (diff) {
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const unsigned char *prev = begin;
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for (k = i + 2; k < x && len < 128; ++k) {
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if (memcmp(prev, row + k * comp, comp)) {
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prev += comp;
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++len;
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} else {
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--len;
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break;
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}
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}
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} else {
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for (k = i + 2; k < x && len < 128; ++k) {
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if (!memcmp(begin, row + k * comp, comp)) {
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++len;
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} else {
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break;
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}
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}
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}
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}
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if (diff) {
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unsigned char header = STBIW_UCHAR(len - 1);
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s->func(s->context, &header, 1);
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for (k = 0; k < len; ++k) {
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stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp);
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}
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} else {
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unsigned char header = STBIW_UCHAR(len - 129);
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s->func(s->context, &header, 1);
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stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin);
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}
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}
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}
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}
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return 1;
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}
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int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, int y,
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int comp, const void *data) {
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stbi__write_context s;
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stbi__start_write_callbacks(&s, func, context);
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return stbi_write_tga_core(&s, x, y, comp, (void *)data);
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}
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int stbi_write_tga(char const *filename, int x, int y, int comp,
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const void *data) {
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stbi__write_context s;
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if (stbi__start_write_file(&s, filename)) {
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int r = stbi_write_tga_core(&s, x, y, comp, (void *)data);
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stbi__end_write_file(&s);
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return r;
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} else
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return 0;
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}
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/* JPEG writer
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*
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* This is based on Jon Olick's jo_jpeg.cpp:
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* public domain Simple, Minimalistic JPEG writer -
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* http://www.jonolick.com/code.html
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*/
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static const unsigned char stbiw__jpg_ZigZag[] = {
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0, 1, 5, 6, 14, 15, 27, 28, 2, 4, 7, 13, 16, 26, 29, 42,
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3, 8, 12, 17, 25, 30, 41, 43, 9, 11, 18, 24, 31, 40, 44, 53,
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10, 19, 23, 32, 39, 45, 52, 54, 20, 22, 33, 38, 46, 51, 55, 60,
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21, 34, 37, 47, 50, 56, 59, 61, 35, 36, 48, 49, 57, 58, 62, 63,
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};
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static void stbiw__jpg_writeBits(stbi__write_context *s, int *bitBufP,
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int *bitCntP, const unsigned short *bs) {
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unsigned char c;
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unsigned bitBuf, bitCnt;
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bitBuf = *bitBufP;
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bitCnt = *bitCntP;
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bitCnt += bs[1];
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bitBuf |= bs[0] << (24 - bitCnt);
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while (bitCnt >= 8) {
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c = (bitBuf >> 16) & 255;
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stbiw__putc(s, c);
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if (c == 255) {
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stbiw__putc(s, 0);
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}
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bitBuf <<= 8;
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bitCnt -= 8;
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}
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*bitBufP = bitBuf;
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*bitCntP = bitCnt;
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}
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static void stbiw__jpg_calcBits(int val, unsigned short bits[2]) {
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int tmp1 = val < 0 ? -val : val;
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val = val < 0 ? val - 1 : val;
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bits[1] = 1;
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while (tmp1 >>= 1) {
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++bits[1];
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}
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bits[0] = val & ((1u << bits[1]) - 1);
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}
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|
|
static int stbiw__jpg_processDU(stbi__write_context *s, int *bitBuf,
|
|
int *bitCnt, float *CDU, float *fdtbl, int DC,
|
|
const unsigned short HTDC[256][2],
|
|
const unsigned short HTAC[256][2]) {
|
|
const unsigned short EOB[2] = {HTAC[0x00][0], HTAC[0x00][1]};
|
|
const unsigned short M16zeroes[2] = {HTAC[0xF0][0], HTAC[0xF0][1]};
|
|
unsigned i, diff, end0pos;
|
|
int DU[64];
|
|
|
|
dctjpeg((void *)CDU);
|
|
|
|
// Quantize/descale/zigzag the coefficients
|
|
for (i = 0; i < 64; ++i) {
|
|
float v = CDU[i] * fdtbl[i];
|
|
DU[stbiw__jpg_ZigZag[i]] = v < 0 ? ceilf(v - 0.5f) : floorf(v + 0.5f);
|
|
// DU[stbiw__jpg_ZigZag[i]] = (int)(v < 0 ? ceilf(v - 0.5f) : floorf(v +
|
|
// 0.5f)); ceilf() and floorf() are C99, not C89, but I /think/ they're not
|
|
// needed here anyway?
|
|
/* DU[stbiw__jpg_ZigZag[i]] = (int)(v < 0 ? v - 0.5f : v + 0.5f); */
|
|
}
|
|
|
|
// Encode DC
|
|
diff = DU[0] - DC;
|
|
if (diff == 0) {
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[0]);
|
|
} else {
|
|
unsigned short bits[2];
|
|
stbiw__jpg_calcBits(diff, bits);
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[bits[1]]);
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits);
|
|
}
|
|
// Encode ACs
|
|
end0pos = 63;
|
|
for (; (end0pos > 0) && (DU[end0pos] == 0); --end0pos) {
|
|
}
|
|
// end0pos = first element in reverse order !=0
|
|
if (end0pos == 0) {
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB);
|
|
return DU[0];
|
|
}
|
|
for (i = 1; i <= end0pos; ++i) {
|
|
unsigned startpos = i;
|
|
unsigned nrzeroes;
|
|
unsigned short bits[2];
|
|
for (; DU[i] == 0 && i <= end0pos; ++i) {
|
|
}
|
|
nrzeroes = i - startpos;
|
|
if (nrzeroes >= 16) {
|
|
unsigned lng = nrzeroes >> 4;
|
|
unsigned nrmarker;
|
|
for (nrmarker = 1; nrmarker <= lng; ++nrmarker) {
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, M16zeroes);
|
|
}
|
|
nrzeroes &= 15;
|
|
}
|
|
stbiw__jpg_calcBits(DU[i], bits);
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTAC[(nrzeroes << 4) + bits[1]]);
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits);
|
|
}
|
|
if (end0pos != 63) {
|
|
stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB);
|
|
}
|
|
return DU[0];
|
|
}
|
|
|
|
static int stbi_write_jpg_core(stbi__write_context *s, int width, int height,
|
|
int comp, const void *data, int quality) {
|
|
static const unsigned char std_dc_luminance_nrcodes[] = {
|
|
0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0};
|
|
static const unsigned char std_dc_luminance_values[] = {0, 1, 2, 3, 4, 5,
|
|
6, 7, 8, 9, 10, 11};
|
|
static const unsigned char std_ac_luminance_nrcodes[] = {
|
|
0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d};
|
|
static const unsigned char std_ac_luminance_values[] = {
|
|
0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06,
|
|
0x13, 0x51, 0x61, 0x07, 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
|
|
0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0, 0x24, 0x33, 0x62, 0x72,
|
|
0x82, 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
|
|
0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45,
|
|
0x46, 0x47, 0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
|
|
0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x73, 0x74, 0x75,
|
|
0x76, 0x77, 0x78, 0x79, 0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
|
|
0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3,
|
|
0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
|
|
0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9,
|
|
0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
|
|
0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4,
|
|
0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa};
|
|
static const unsigned char std_dc_chrominance_nrcodes[] = {
|
|
0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0};
|
|
static const unsigned char std_dc_chrominance_values[] = {0, 1, 2, 3, 4, 5,
|
|
6, 7, 8, 9, 10, 11};
|
|
static const unsigned char std_ac_chrominance_nrcodes[] = {
|
|
0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77};
|
|
static const unsigned char std_ac_chrominance_values[] = {
|
|
0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06, 0x12, 0x41,
|
|
0x51, 0x07, 0x61, 0x71, 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
|
|
0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0, 0x15, 0x62, 0x72, 0xd1,
|
|
0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
|
|
0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44,
|
|
0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
|
|
0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x73, 0x74,
|
|
0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
|
|
0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a,
|
|
0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
|
|
0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
|
|
0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
|
|
0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf2, 0xf3, 0xf4,
|
|
0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa};
|
|
// Huffman tables
|
|
static const unsigned short YDC_HT[256][2] = {
|
|
{0, 2}, {2, 3}, {3, 3}, {4, 3}, {5, 3}, {6, 3},
|
|
{14, 4}, {30, 5}, {62, 6}, {126, 7}, {254, 8}, {510, 9}};
|
|
static const unsigned short UVDC_HT[256][2] = {
|
|
{0, 2}, {1, 2}, {2, 2}, {6, 3}, {14, 4}, {30, 5},
|
|
{62, 6}, {126, 7}, {254, 8}, {510, 9}, {1022, 10}, {2046, 11}};
|
|
static const unsigned short YAC_HT[256][2] = {
|
|
{10, 4}, {0, 2}, {1, 2}, {4, 3}, {11, 4},
|
|
{26, 5}, {120, 7}, {248, 8}, {1014, 10}, {65410, 16},
|
|
{65411, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {12, 4}, {27, 5}, {121, 7},
|
|
{502, 9}, {2038, 11}, {65412, 16}, {65413, 16}, {65414, 16},
|
|
{65415, 16}, {65416, 16}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {28, 5}, {249, 8},
|
|
{1015, 10}, {4084, 12}, {65417, 16}, {65418, 16}, {65419, 16},
|
|
{65420, 16}, {65421, 16}, {65422, 16}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {58, 6},
|
|
{503, 9}, {4085, 12}, {65423, 16}, {65424, 16}, {65425, 16},
|
|
{65426, 16}, {65427, 16}, {65428, 16}, {65429, 16}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{59, 6}, {1016, 10}, {65430, 16}, {65431, 16}, {65432, 16},
|
|
{65433, 16}, {65434, 16}, {65435, 16}, {65436, 16}, {65437, 16},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {122, 7}, {2039, 11}, {65438, 16}, {65439, 16},
|
|
{65440, 16}, {65441, 16}, {65442, 16}, {65443, 16}, {65444, 16},
|
|
{65445, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {123, 7}, {4086, 12}, {65446, 16},
|
|
{65447, 16}, {65448, 16}, {65449, 16}, {65450, 16}, {65451, 16},
|
|
{65452, 16}, {65453, 16}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {250, 8}, {4087, 12},
|
|
{65454, 16}, {65455, 16}, {65456, 16}, {65457, 16}, {65458, 16},
|
|
{65459, 16}, {65460, 16}, {65461, 16}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {504, 9},
|
|
{32704, 15}, {65462, 16}, {65463, 16}, {65464, 16}, {65465, 16},
|
|
{65466, 16}, {65467, 16}, {65468, 16}, {65469, 16}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{505, 9}, {65470, 16}, {65471, 16}, {65472, 16}, {65473, 16},
|
|
{65474, 16}, {65475, 16}, {65476, 16}, {65477, 16}, {65478, 16},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {506, 9}, {65479, 16}, {65480, 16}, {65481, 16},
|
|
{65482, 16}, {65483, 16}, {65484, 16}, {65485, 16}, {65486, 16},
|
|
{65487, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {1017, 10}, {65488, 16}, {65489, 16},
|
|
{65490, 16}, {65491, 16}, {65492, 16}, {65493, 16}, {65494, 16},
|
|
{65495, 16}, {65496, 16}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {1018, 10}, {65497, 16},
|
|
{65498, 16}, {65499, 16}, {65500, 16}, {65501, 16}, {65502, 16},
|
|
{65503, 16}, {65504, 16}, {65505, 16}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {2040, 11},
|
|
{65506, 16}, {65507, 16}, {65508, 16}, {65509, 16}, {65510, 16},
|
|
{65511, 16}, {65512, 16}, {65513, 16}, {65514, 16}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{65515, 16}, {65516, 16}, {65517, 16}, {65518, 16}, {65519, 16},
|
|
{65520, 16}, {65521, 16}, {65522, 16}, {65523, 16}, {65524, 16},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{2041, 11}, {65525, 16}, {65526, 16}, {65527, 16}, {65528, 16},
|
|
{65529, 16}, {65530, 16}, {65531, 16}, {65532, 16}, {65533, 16},
|
|
{65534, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}};
|
|
static const unsigned short UVAC_HT[256][2] = {
|
|
{0, 2}, {1, 2}, {4, 3}, {10, 4}, {24, 5},
|
|
{25, 5}, {56, 6}, {120, 7}, {500, 9}, {1014, 10},
|
|
{4084, 12}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {11, 4}, {57, 6}, {246, 8},
|
|
{501, 9}, {2038, 11}, {4085, 12}, {65416, 16}, {65417, 16},
|
|
{65418, 16}, {65419, 16}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {26, 5}, {247, 8},
|
|
{1015, 10}, {4086, 12}, {32706, 15}, {65420, 16}, {65421, 16},
|
|
{65422, 16}, {65423, 16}, {65424, 16}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {27, 5},
|
|
{248, 8}, {1016, 10}, {4087, 12}, {65425, 16}, {65426, 16},
|
|
{65427, 16}, {65428, 16}, {65429, 16}, {65430, 16}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{58, 6}, {502, 9}, {65431, 16}, {65432, 16}, {65433, 16},
|
|
{65434, 16}, {65435, 16}, {65436, 16}, {65437, 16}, {65438, 16},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {59, 6}, {1017, 10}, {65439, 16}, {65440, 16},
|
|
{65441, 16}, {65442, 16}, {65443, 16}, {65444, 16}, {65445, 16},
|
|
{65446, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {121, 7}, {2039, 11}, {65447, 16},
|
|
{65448, 16}, {65449, 16}, {65450, 16}, {65451, 16}, {65452, 16},
|
|
{65453, 16}, {65454, 16}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {122, 7}, {2040, 11},
|
|
{65455, 16}, {65456, 16}, {65457, 16}, {65458, 16}, {65459, 16},
|
|
{65460, 16}, {65461, 16}, {65462, 16}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {249, 8},
|
|
{65463, 16}, {65464, 16}, {65465, 16}, {65466, 16}, {65467, 16},
|
|
{65468, 16}, {65469, 16}, {65470, 16}, {65471, 16}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{503, 9}, {65472, 16}, {65473, 16}, {65474, 16}, {65475, 16},
|
|
{65476, 16}, {65477, 16}, {65478, 16}, {65479, 16}, {65480, 16},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {504, 9}, {65481, 16}, {65482, 16}, {65483, 16},
|
|
{65484, 16}, {65485, 16}, {65486, 16}, {65487, 16}, {65488, 16},
|
|
{65489, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {505, 9}, {65490, 16}, {65491, 16},
|
|
{65492, 16}, {65493, 16}, {65494, 16}, {65495, 16}, {65496, 16},
|
|
{65497, 16}, {65498, 16}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {506, 9}, {65499, 16},
|
|
{65500, 16}, {65501, 16}, {65502, 16}, {65503, 16}, {65504, 16},
|
|
{65505, 16}, {65506, 16}, {65507, 16}, {0, 0}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {2041, 11},
|
|
{65508, 16}, {65509, 16}, {65510, 16}, {65511, 16}, {65512, 16},
|
|
{65513, 16}, {65514, 16}, {65515, 16}, {65516, 16}, {0, 0},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{16352, 14}, {65517, 16}, {65518, 16}, {65519, 16}, {65520, 16},
|
|
{65521, 16}, {65522, 16}, {65523, 16}, {65524, 16}, {65525, 16},
|
|
{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{1018, 10}, {32707, 15}, {65526, 16}, {65527, 16}, {65528, 16},
|
|
{65529, 16}, {65530, 16}, {65531, 16}, {65532, 16}, {65533, 16},
|
|
{65534, 16}, {0, 0}, {0, 0}, {0, 0}, {0, 0},
|
|
{0, 0}};
|
|
static const int YQT[] = {
|
|
16, 11, 10, 16, 24, 40, 51, 61, 12, 12, 14, 19, 26, 58, 60, 55,
|
|
14, 13, 16, 24, 40, 57, 69, 56, 14, 17, 22, 29, 51, 87, 80, 62,
|
|
18, 22, 37, 56, 68, 109, 103, 77, 24, 35, 55, 64, 81, 104, 113, 92,
|
|
49, 64, 78, 87, 103, 121, 120, 101, 72, 92, 95, 98, 112, 100, 103, 99};
|
|
static const int UVQT[] = {17, 18, 24, 47, 99, 99, 99, 99, 18, 21, 26, 66, 99,
|
|
99, 99, 99, 24, 26, 56, 99, 99, 99, 99, 99, 47, 66,
|
|
99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
|
|
99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99,
|
|
99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99};
|
|
static const float aasf[] = {
|
|
1.0f * 2.828427125f, 1.387039845f * 2.828427125f,
|
|
1.306562965f * 2.828427125f, 1.175875602f * 2.828427125f,
|
|
1.0f * 2.828427125f, 0.785694958f * 2.828427125f,
|
|
0.541196100f * 2.828427125f, 0.275899379f * 2.828427125f};
|
|
|
|
int row, col, i, k;
|
|
float fdtbl_Y[64], fdtbl_UV[64];
|
|
unsigned char YTable[64], UVTable[64];
|
|
|
|
if (!data || !width || !height || comp > 4 || comp < 1) {
|
|
return 0;
|
|
}
|
|
|
|
quality = quality ? quality : 97;
|
|
quality = quality < 1 ? 1 : quality > 100 ? 100 : quality;
|
|
quality = quality < 50 ? 5000 / quality : 200 - quality * 2;
|
|
|
|
for (i = 0; i < 64; ++i) {
|
|
int uvti, yti = div100int64((YQT[i] * quality + 50));
|
|
YTable[stbiw__jpg_ZigZag[i]] =
|
|
(unsigned char)(yti < 1 ? 1 : yti > 255 ? 255 : yti);
|
|
uvti = div100int64(UVQT[i] * quality + 50);
|
|
UVTable[stbiw__jpg_ZigZag[i]] =
|
|
(unsigned char)(uvti < 1 ? 1 : uvti > 255 ? 255 : uvti);
|
|
}
|
|
|
|
for (row = 0, k = 0; row < 8; ++row) {
|
|
for (col = 0; col < 8; ++col, ++k) {
|
|
fdtbl_Y[k] = 1 / (YTable[stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]);
|
|
fdtbl_UV[k] = 1 / (UVTable[stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]);
|
|
}
|
|
}
|
|
|
|
// Write Headers
|
|
{
|
|
static const unsigned char head0[] = {
|
|
0xFF, 0xD8, 0xFF, 0xE0, 0, 0x10, 'J', 'F', 'I', 'F', 0, 1, 1,
|
|
0, 0, 1, 0, 1, 0, 0, 0xFF, 0xDB, 0, 0x84, 0};
|
|
static const unsigned char head2[] = {0xFF, 0xDA, 0, 0xC, 3, 1, 0,
|
|
2, 0x11, 3, 0x11, 0, 0x3F, 0};
|
|
const unsigned char head1[] = {
|
|
0xFF,
|
|
0xC0,
|
|
0,
|
|
0x11,
|
|
8,
|
|
(unsigned char)(height >> 8),
|
|
STBIW_UCHAR(height),
|
|
(unsigned char)(width >> 8),
|
|
STBIW_UCHAR(width),
|
|
3,
|
|
1,
|
|
0x11,
|
|
0,
|
|
2,
|
|
0x11,
|
|
1,
|
|
3,
|
|
0x11,
|
|
1,
|
|
0xFF,
|
|
0xC4,
|
|
0x01,
|
|
0xA2,
|
|
0,
|
|
};
|
|
s->func(s->context, (void *)head0, sizeof(head0));
|
|
s->func(s->context, (void *)YTable, sizeof(YTable));
|
|
stbiw__putc(s, 1);
|
|
s->func(s->context, UVTable, sizeof(UVTable));
|
|
s->func(s->context, (void *)head1, sizeof(head1));
|
|
s->func(s->context, (void *)(std_dc_luminance_nrcodes + 1),
|
|
sizeof(std_dc_luminance_nrcodes) - 1);
|
|
s->func(s->context, (void *)std_dc_luminance_values,
|
|
sizeof(std_dc_luminance_values));
|
|
stbiw__putc(s, 0x10); // HTYACinfo
|
|
s->func(s->context, (void *)(std_ac_luminance_nrcodes + 1),
|
|
sizeof(std_ac_luminance_nrcodes) - 1);
|
|
s->func(s->context, (void *)std_ac_luminance_values,
|
|
sizeof(std_ac_luminance_values));
|
|
stbiw__putc(s, 1); // HTUDCinfo
|
|
s->func(s->context, (void *)(std_dc_chrominance_nrcodes + 1),
|
|
sizeof(std_dc_chrominance_nrcodes) - 1);
|
|
s->func(s->context, (void *)std_dc_chrominance_values,
|
|
sizeof(std_dc_chrominance_values));
|
|
stbiw__putc(s, 0x11); // HTUACinfo
|
|
s->func(s->context, (void *)(std_ac_chrominance_nrcodes + 1),
|
|
sizeof(std_ac_chrominance_nrcodes) - 1);
|
|
s->func(s->context, (void *)std_ac_chrominance_values,
|
|
sizeof(std_ac_chrominance_values));
|
|
s->func(s->context, (void *)head2, sizeof(head2));
|
|
}
|
|
|
|
// Encode 8x8 macroblocks
|
|
{
|
|
static const unsigned short fillBits[] = {0x7F, 7};
|
|
const unsigned char *imageData = (const unsigned char *)data;
|
|
int DCY = 0, DCU = 0, DCV = 0;
|
|
int bitBuf = 0, bitCnt = 0;
|
|
// comp == 2 is grey+alpha (alpha is ignored)
|
|
int ofsG = comp > 2 ? 1 : 0, ofsB = comp > 2 ? 2 : 0;
|
|
int x, y, pos;
|
|
for (y = 0; y < height; y += 8) {
|
|
for (x = 0; x < width; x += 8) {
|
|
float YDU[64], UDU[64], VDU[64];
|
|
for (row = y, pos = 0; row < y + 8; ++row) {
|
|
// row >= height => use last input row
|
|
int clamped_row = (row < height) ? row : height - 1;
|
|
int base_p =
|
|
(stbi__flip_vertically_on_write ? (height - 1 - clamped_row)
|
|
: clamped_row) *
|
|
width * comp;
|
|
for (col = x; col < x + 8; ++col, ++pos) {
|
|
float r, g, b;
|
|
// if col >= width => use pixel from last input column
|
|
int p = base_p + ((col < width) ? col : (width - 1)) * comp;
|
|
|
|
r = imageData[p + 0];
|
|
g = imageData[p + ofsG];
|
|
b = imageData[p + ofsB];
|
|
YDU[pos] = +0.29900f * r + 0.58700f * g + 0.11400f * b - 128;
|
|
UDU[pos] = -0.16874f * r - 0.33126f * g + 0.50000f * b;
|
|
VDU[pos] = +0.50000f * r - 0.41869f * g - 0.08131f * b;
|
|
}
|
|
}
|
|
|
|
DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, YDU, fdtbl_Y, DCY,
|
|
YDC_HT, YAC_HT);
|
|
DCU = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, UDU, fdtbl_UV, DCU,
|
|
UVDC_HT, UVAC_HT);
|
|
DCV = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, VDU, fdtbl_UV, DCV,
|
|
UVDC_HT, UVAC_HT);
|
|
}
|
|
}
|
|
|
|
// Do the bit alignment of the EOI marker
|
|
stbiw__jpg_writeBits(s, &bitBuf, &bitCnt, fillBits);
|
|
}
|
|
|
|
// EOI
|
|
stbiw__putc(s, 0xFF);
|
|
stbiw__putc(s, 0xD9);
|
|
|
|
return 1;
|
|
}
|
|
|
|
int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y,
|
|
int comp, const void *data, int quality) {
|
|
stbi__write_context s;
|
|
stbi__start_write_callbacks(&s, func, context);
|
|
return stbi_write_jpg_core(&s, x, y, comp, (void *)data, quality);
|
|
}
|
|
|
|
int stbi_write_jpg(char const *filename, int x, int y, int comp,
|
|
const void *data, int quality) {
|
|
stbi__write_context s;
|
|
if (stbi__start_write_file(&s, filename)) {
|
|
int r = stbi_write_jpg_core(&s, x, y, comp, data, quality);
|
|
stbi__end_write_file(&s);
|
|
return r;
|
|
} else
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
********************************************************************************
|
|
Radiance RGBE HDR writer
|
|
by Baldur Karlsson */
|
|
|
|
static void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear) {
|
|
int exponent;
|
|
float normalize, maxcomp;
|
|
maxcomp = MAX(linear[0], MAX(linear[1], linear[2]));
|
|
if (maxcomp < 1e-32f) {
|
|
rgbe[0] = rgbe[1] = rgbe[2] = rgbe[3] = 0;
|
|
} else {
|
|
/* no idea what HDR is but this could probably use clamping */
|
|
normalize = (float)frexp(maxcomp, &exponent) * 256.0f / maxcomp;
|
|
rgbe[0] = (unsigned char)(linear[0] * normalize);
|
|
rgbe[1] = (unsigned char)(linear[1] * normalize);
|
|
rgbe[2] = (unsigned char)(linear[2] * normalize);
|
|
rgbe[3] = (unsigned char)(exponent + 128);
|
|
}
|
|
}
|
|
|
|
static void stbiw__write_run_data(stbi__write_context *s, int length,
|
|
unsigned char databyte) {
|
|
unsigned char lengthbyte = STBIW_UCHAR(length + 128);
|
|
assert(length + 128 <= 255);
|
|
s->func(s->context, &lengthbyte, 1);
|
|
s->func(s->context, &databyte, 1);
|
|
}
|
|
|
|
static void stbiw__write_dump_data(stbi__write_context *s, int length,
|
|
unsigned char *data) {
|
|
unsigned char lengthbyte = STBIW_UCHAR(length);
|
|
assert(length <=
|
|
128); // inconsistent with spec but consistent with official code
|
|
s->func(s->context, &lengthbyte, 1);
|
|
s->func(s->context, data, length);
|
|
}
|
|
|
|
static void stbiw__write_hdr_scanline(stbi__write_context *s, int width,
|
|
int ncomp, unsigned char *scratch,
|
|
float *scanline) {
|
|
unsigned char scanlineheader[4] = {2, 2, 0, 0};
|
|
unsigned char rgbe[4];
|
|
float linear[3];
|
|
int x;
|
|
|
|
scanlineheader[2] = (width & 0xff00) >> 8;
|
|
scanlineheader[3] = (width & 0x00ff);
|
|
|
|
/* skip RLE for images too small or large */
|
|
if (width < 8 || width >= 32768) {
|
|
for (x = 0; x < width; x++) {
|
|
switch (ncomp) {
|
|
case 4: /* fallthrough */
|
|
case 3:
|
|
linear[2] = scanline[x * ncomp + 2];
|
|
linear[1] = scanline[x * ncomp + 1];
|
|
linear[0] = scanline[x * ncomp + 0];
|
|
break;
|
|
default:
|
|
linear[0] = linear[1] = linear[2] = scanline[x * ncomp + 0];
|
|
break;
|
|
}
|
|
stbiw__linear_to_rgbe(rgbe, linear);
|
|
s->func(s->context, rgbe, 4);
|
|
}
|
|
} else {
|
|
int c, r;
|
|
/* encode into scratch buffer */
|
|
for (x = 0; x < width; x++) {
|
|
switch (ncomp) {
|
|
case 4: /* fallthrough */
|
|
case 3:
|
|
linear[2] = scanline[x * ncomp + 2];
|
|
linear[1] = scanline[x * ncomp + 1];
|
|
linear[0] = scanline[x * ncomp + 0];
|
|
break;
|
|
default:
|
|
linear[0] = linear[1] = linear[2] = scanline[x * ncomp + 0];
|
|
break;
|
|
}
|
|
stbiw__linear_to_rgbe(rgbe, linear);
|
|
scratch[x + width * 0] = rgbe[0];
|
|
scratch[x + width * 1] = rgbe[1];
|
|
scratch[x + width * 2] = rgbe[2];
|
|
scratch[x + width * 3] = rgbe[3];
|
|
}
|
|
|
|
s->func(s->context, scanlineheader, 4);
|
|
|
|
/* RLE each component separately */
|
|
for (c = 0; c < 4; c++) {
|
|
unsigned char *comp = &scratch[width * c];
|
|
|
|
x = 0;
|
|
while (x < width) {
|
|
// find first run
|
|
r = x;
|
|
while (r + 2 < width) {
|
|
if (comp[r] == comp[r + 1] && comp[r] == comp[r + 2]) break;
|
|
++r;
|
|
}
|
|
if (r + 2 >= width) r = width;
|
|
// dump up to first run
|
|
while (x < r) {
|
|
int len = r - x;
|
|
if (len > 128) len = 128;
|
|
stbiw__write_dump_data(s, len, &comp[x]);
|
|
x += len;
|
|
}
|
|
// if there's a run, output it
|
|
if (r + 2 < width) { // same test as what we break out of in search
|
|
// loop, so only true if we break'd
|
|
// find next byte after run
|
|
while (r < width && comp[r] == comp[x]) ++r;
|
|
// output run up to r
|
|
while (x < r) {
|
|
int len = r - x;
|
|
if (len > 127) len = 127;
|
|
stbiw__write_run_data(s, len, comp[x]);
|
|
x += len;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int stbi_write_hdr_core(stbi__write_context *s, int x, int y, int comp,
|
|
float *data) {
|
|
if (y <= 0 || x <= 0 || data == NULL)
|
|
return 0;
|
|
else {
|
|
// Each component is stored separately. Allocate scratch space for full
|
|
// output scanline.
|
|
unsigned char *scratch = malloc(x * 4);
|
|
int i, len;
|
|
char buffer[128];
|
|
char header[] =
|
|
"#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n";
|
|
s->func(s->context, header, sizeof(header) - 1);
|
|
len = (snprintf)(buffer, sizeof(buffer), "%s\n\n%s%d%s%d\n",
|
|
"EXPOSURE= 1.0000000000000", "-Y ", y, " +X ", x);
|
|
s->func(s->context, buffer, len);
|
|
for (i = 0; i < y; i++) {
|
|
stbiw__write_hdr_scanline(
|
|
s, x, comp, scratch,
|
|
data + comp * x * (stbi__flip_vertically_on_write ? y - 1 - i : i));
|
|
}
|
|
free(scratch);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int x, int y,
|
|
int comp, const float *data) {
|
|
stbi__write_context s;
|
|
stbi__start_write_callbacks(&s, func, context);
|
|
return stbi_write_hdr_core(&s, x, y, comp, (float *)data);
|
|
}
|
|
|
|
int stbi_write_hdr(char const *filename, int x, int y, int comp,
|
|
const float *data) {
|
|
stbi__write_context s;
|
|
if (stbi__start_write_file(&s, filename)) {
|
|
int r = stbi_write_hdr_core(&s, x, y, comp, (float *)data);
|
|
stbi__end_write_file(&s);
|
|
return r;
|
|
} else
|
|
return 0;
|
|
}
|