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ab8f16961e
Apply clang-format-all.sh using the _clang-format file through all the cpp/.h files. make sure not to apply it to certain serialization structures, since some parser expects the * as part of the name, instead of type. This commit contains no other changes aside from adding and applying clang-format-all.sh
609 lines
17 KiB
C
609 lines
17 KiB
C
/* stbiw-0.92 - public domain - http://nothings.org/stb/stb_image_write.h
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writes out PNG/BMP/TGA images to C stdio - Sean Barrett 2010
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no warranty implied; use at your own risk
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Before including,
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#define STB_IMAGE_WRITE_IMPLEMENTATION
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in the file that you want to have the implementation.
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ABOUT:
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This header file is a library for writing images to C stdio. It could be
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adapted to write to memory or a general streaming interface; let me know.
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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. This library is designed
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for source code compactness and simplicitly, not optimal image file size
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or run-time performance.
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USAGE:
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There are three functions, one for each image file format:
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int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes);
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int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data);
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int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data);
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Each function returns 0 on failure and non-0 on success.
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The functions create an image file defined by the parameters. The image
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is a rectangle of pixels stored from left-to-right, top-to-bottom.
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Each pixel contains 'comp' channels of data stored interleaved with 8-bits
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per channel, in the following order: 1=Y, 2=YA, 3=RGB, 4=RGBA. (Y is
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monochrome color.) The rectangle is 'w' pixels wide and 'h' pixels tall.
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The *data pointer points to the first byte of the top-left-most pixel.
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For PNG, "stride_in_bytes" is the distance in bytes from the first byte of
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a row of pixels to the first byte of the next row of pixels.
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PNG creates output files with the same number of components as the input.
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The BMP and TGA formats expand Y to RGB in the file format. BMP does not
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output alpha.
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PNG supports writing rectangles of data even when the bytes storing rows of
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data are not consecutive in memory (e.g. sub-rectangles of a larger image),
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by supplying the stride between the beginning of adjacent rows. The other
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formats do not. (Thus you cannot write a native-format BMP through the BMP
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writer, both because it is in BGR order and because it may have padding
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at the end of the line.)
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*/
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#ifndef INCLUDE_STB_IMAGE_WRITE_H
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#define INCLUDE_STB_IMAGE_WRITE_H
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#ifdef __cplusplus
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extern "C"
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{
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#endif
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extern int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes);
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extern int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data);
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extern int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data);
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#ifdef __cplusplus
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}
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#endif
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#endif //INCLUDE_STB_IMAGE_WRITE_H
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#ifdef STB_IMAGE_WRITE_IMPLEMENTATION
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#include <stdarg.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <string.h>
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#include <assert.h>
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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 writefv(FILE *f, const char *fmt, va_list v)
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{
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while (*fmt)
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{
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switch (*fmt++)
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{
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case ' ':
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break;
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case '1':
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{
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unsigned char x = (unsigned char)va_arg(v, int);
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fputc(x, f);
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break;
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}
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case '2':
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{
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int x = va_arg(v, int);
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unsigned char b[2];
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b[0] = (unsigned char)x;
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b[1] = (unsigned char)(x >> 8);
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fwrite(b, 2, 1, f);
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break;
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}
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case '4':
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{
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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] = (unsigned char)x;
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b[1] = (unsigned char)(x >> 8);
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b[2] = (unsigned char)(x >> 16);
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b[3] = (unsigned char)(x >> 24);
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fwrite(b, 4, 1, f);
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break;
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}
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default:
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assert(0);
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return;
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}
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}
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}
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static void write3(FILE *f, unsigned char a, unsigned char b, unsigned char c)
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{
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unsigned char arr[3];
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arr[0] = a, arr[1] = b, arr[2] = c;
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fwrite(arr, 3, 1, f);
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}
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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)
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{
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unsigned char bg[3] = {255, 0, 255}, px[3];
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stbiw_uint32 zero = 0;
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int i, j, k, j_end;
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if (y <= 0)
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return;
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if (vdir < 0)
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j_end = -1, j = y - 1;
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else
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j_end = y, j = 0;
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for (; j != j_end; j += vdir)
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{
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for (i = 0; i < x; ++i)
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{
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unsigned char *d = (unsigned char *)data + (j * x + i) * comp;
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if (write_alpha < 0)
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fwrite(&d[comp - 1], 1, 1, f);
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switch (comp)
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{
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case 1:
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case 2:
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write3(f, d[0], d[0], d[0]);
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break;
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case 4:
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if (!write_alpha)
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{
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// composite against pink background
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for (k = 0; k < 3; ++k)
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px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255;
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write3(f, 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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write3(f, 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)
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fwrite(&d[comp - 1], 1, 1, f);
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}
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fwrite(&zero, scanline_pad, 1, f);
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}
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}
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static int outfile(char const *filename, int rgb_dir, int vdir, int x, int y, int comp, void *data, int alpha, int pad, const char *fmt, ...)
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{
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FILE *f;
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if (y < 0 || x < 0) return 0;
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f = fopen(filename, "wb");
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if (f)
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{
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va_list v;
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va_start(v, fmt);
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writefv(f, fmt, v);
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va_end(v);
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write_pixels(f, rgb_dir, vdir, x, y, comp, data, alpha, pad);
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fclose(f);
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}
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return f != NULL;
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}
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int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data)
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{
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int pad = (-x * 3) & 3;
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return outfile(filename, -1, -1, x, y, comp, (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, 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_tga(char const *filename, int x, int y, int comp, const void *data)
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{
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int has_alpha = !(comp & 1);
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return outfile(filename, -1, -1, x, y, comp, (void *)data, has_alpha, 0,
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"111 221 2222 11", 0, 0, 2, 0, 0, 0, 0, 0, x, y, 24 + 8 * has_alpha, 8 * has_alpha);
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}
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// stretchy buffer; stbi__sbpush() == vector<>::push_back() -- stbi__sbcount() == vector<>::size()
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#define stbi__sbraw(a) ((int *)(a)-2)
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#define stbi__sbm(a) stbi__sbraw(a)[0]
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#define stbi__sbn(a) stbi__sbraw(a)[1]
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#define stbi__sbneedgrow(a, n) ((a) == 0 || stbi__sbn(a) + n >= stbi__sbm(a))
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#define stbi__sbmaybegrow(a, n) (stbi__sbneedgrow(a, (n)) ? stbi__sbgrow(a, n) : 0)
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#define stbi__sbgrow(a, n) stbi__sbgrowf((void **)&(a), (n), sizeof(*(a)))
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#define stbi__sbpush(a, v) (stbi__sbmaybegrow(a, 1), (a)[stbi__sbn(a)++] = (v))
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#define stbi__sbcount(a) ((a) ? stbi__sbn(a) : 0)
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#define stbi__sbfree(a) ((a) ? free(stbi__sbraw(a)), 0 : 0)
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static void *stbi__sbgrowf(void **arr, int increment, int itemsize)
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{
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int m = *arr ? 2 * stbi__sbm(*arr) + increment : increment + 1;
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void *p = realloc(*arr ? stbi__sbraw(*arr) : 0, itemsize * m + sizeof(int) * 2);
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assert(p);
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if (p)
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{
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if (!*arr) ((int *)p)[1] = 0;
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*arr = (void *)((int *)p + 2);
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stbi__sbm(*arr) = m;
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}
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return *arr;
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}
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static unsigned char *stbi__zlib_flushf(unsigned char *data, unsigned int *bitbuffer, int *bitcount)
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{
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while (*bitcount >= 8)
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{
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stbi__sbpush(data, (unsigned char)*bitbuffer);
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*bitbuffer >>= 8;
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*bitcount -= 8;
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}
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return data;
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}
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static int stbi__zlib_bitrev(int code, int codebits)
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{
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int res = 0;
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while (codebits--)
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{
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res = (res << 1) | (code & 1);
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code >>= 1;
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}
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return res;
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}
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static unsigned int stbi__zlib_countm(unsigned char *a, unsigned char *b, int limit)
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{
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int i;
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for (i = 0; i < limit && i < 258; ++i)
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if (a[i] != b[i]) break;
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return i;
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}
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static unsigned int stbi__zhash(unsigned char *data)
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{
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stbiw_uint32 hash = data[0] + (data[1] << 8) + (data[2] << 16);
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hash ^= hash << 3;
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hash += hash >> 5;
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hash ^= hash << 4;
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hash += hash >> 17;
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hash ^= hash << 25;
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hash += hash >> 6;
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return hash;
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}
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#define stbi__zlib_flush() (out = stbi__zlib_flushf(out, &bitbuf, &bitcount))
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#define stbi__zlib_add(code, codebits) \
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(bitbuf |= (code) << bitcount, bitcount += (codebits), stbi__zlib_flush())
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#define stbi__zlib_huffa(b, c) stbi__zlib_add(stbi__zlib_bitrev(b, c), c)
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// default huffman tables
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#define stbi__zlib_huff1(n) stbi__zlib_huffa(0x30 + (n), 8)
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#define stbi__zlib_huff2(n) stbi__zlib_huffa(0x190 + (n)-144, 9)
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#define stbi__zlib_huff3(n) stbi__zlib_huffa(0 + (n)-256, 7)
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#define stbi__zlib_huff4(n) stbi__zlib_huffa(0xc0 + (n)-280, 8)
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#define stbi__zlib_huff(n) ((n) <= 143 ? stbi__zlib_huff1(n) : (n) <= 255 ? stbi__zlib_huff2(n) : (n) <= 279 ? stbi__zlib_huff3(n) : stbi__zlib_huff4(n))
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#define stbi__zlib_huffb(n) ((n) <= 143 ? stbi__zlib_huff1(n) : stbi__zlib_huff2(n))
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#define stbi__ZHASH 16384
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unsigned char *stbi_zlib_compress(unsigned char *data, int data_len, int *out_len, int quality)
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{
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static unsigned short lengthc[] = {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, 259};
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static unsigned char lengtheb[] = {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};
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static unsigned short distc[] = {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, 32768};
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static unsigned char disteb[] = {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};
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unsigned int bitbuf = 0;
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int i, j, bitcount = 0;
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unsigned char *out = NULL;
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unsigned char **hash_table[stbi__ZHASH]; // 64KB on the stack!
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if (quality < 5) quality = 5;
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stbi__sbpush(out, 0x78); // DEFLATE 32K window
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stbi__sbpush(out, 0x5e); // FLEVEL = 1
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stbi__zlib_add(1, 1); // BFINAL = 1
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stbi__zlib_add(1, 2); // B3YPE = 1 -- fixed huffman
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for (i = 0; i < stbi__ZHASH; ++i)
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hash_table[i] = NULL;
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i = 0;
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while (i < data_len - 3)
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{
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// hash next 3 bytes of data to be compressed
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int h = stbi__zhash(data + i) & (stbi__ZHASH - 1), best = 3;
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unsigned char *bestloc = 0;
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unsigned char **hlist = hash_table[h];
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int n = stbi__sbcount(hlist);
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for (j = 0; j < n; ++j)
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{
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if (hlist[j] - data > i - 32768)
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{ // if entry lies within window
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int d = stbi__zlib_countm(hlist[j], data + i, data_len - i);
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if (d >= best) best = d, bestloc = hlist[j];
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}
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}
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// when hash table entry is too long, delete half the entries
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if (hash_table[h] && stbi__sbn(hash_table[h]) == 2 * quality)
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{
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memcpy(hash_table[h], hash_table[h] + quality, sizeof(hash_table[h][0]) * quality);
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stbi__sbn(hash_table[h]) = quality;
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}
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stbi__sbpush(hash_table[h], data + i);
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if (bestloc)
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{
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// "lazy matching" - check match at *next* byte, and if it's better, do cur byte as literal
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h = stbi__zhash(data + i + 1) & (stbi__ZHASH - 1);
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hlist = hash_table[h];
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n = stbi__sbcount(hlist);
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for (j = 0; j < n; ++j)
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{
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if (hlist[j] - data > i - 32767)
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{
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int e = stbi__zlib_countm(hlist[j], data + i + 1, data_len - i - 1);
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if (e > best)
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{ // if next match is better, bail on current match
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bestloc = NULL;
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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 (bestloc)
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{
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int d = data + i - bestloc; // distance back
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assert(d <= 32767 && best <= 258);
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for (j = 0; best > lengthc[j + 1] - 1; ++j)
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;
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stbi__zlib_huff(j + 257);
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if (lengtheb[j]) stbi__zlib_add(best - lengthc[j], lengtheb[j]);
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for (j = 0; d > distc[j + 1] - 1; ++j)
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;
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stbi__zlib_add(stbi__zlib_bitrev(j, 5), 5);
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if (disteb[j]) stbi__zlib_add(d - distc[j], disteb[j]);
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i += best;
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}
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else
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{
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stbi__zlib_huffb(data[i]);
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++i;
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}
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}
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// write out final bytes
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for (; i < data_len; ++i)
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stbi__zlib_huffb(data[i]);
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stbi__zlib_huff(256); // end of block
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// pad with 0 bits to byte boundary
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while (bitcount)
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stbi__zlib_add(0, 1);
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for (i = 0; i < stbi__ZHASH; ++i)
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(void)stbi__sbfree(hash_table[i]);
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{
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// compute adler32 on input
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unsigned int i = 0, s1 = 1, s2 = 0, blocklen = data_len % 5552;
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int j = 0;
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while (j < data_len)
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{
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for (i = 0; i < blocklen; ++i) s1 += data[j + i], s2 += s1;
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s1 %= 65521, s2 %= 65521;
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j += blocklen;
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blocklen = 5552;
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}
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stbi__sbpush(out, (unsigned char)(s2 >> 8));
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stbi__sbpush(out, (unsigned char)s2);
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stbi__sbpush(out, (unsigned char)(s1 >> 8));
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stbi__sbpush(out, (unsigned char)s1);
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}
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*out_len = stbi__sbn(out);
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// make returned pointer freeable
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memmove(stbi__sbraw(out), out, *out_len);
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return (unsigned char *)stbi__sbraw(out);
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}
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unsigned int stbi__crc32(unsigned char *buffer, int len)
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{
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static unsigned int crc_table[256];
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unsigned int crc = ~0u;
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int i, j;
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if (crc_table[1] == 0)
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for (i = 0; i < 256; i++)
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for (crc_table[i] = i, j = 0; j < 8; ++j)
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crc_table[i] = (crc_table[i] >> 1) ^ (crc_table[i] & 1 ? 0xedb88320 : 0);
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for (i = 0; i < len; ++i)
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crc = (crc >> 8) ^ crc_table[buffer[i] ^ (crc & 0xff)];
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return ~crc;
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}
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#define stbi__wpng4(o, a, b, c, d) ((o)[0] = (unsigned char)(a), (o)[1] = (unsigned char)(b), (o)[2] = (unsigned char)(c), (o)[3] = (unsigned char)(d), (o) += 4)
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#define stbi__wp32(data, v) stbi__wpng4(data, (v) >> 24, (v) >> 16, (v) >> 8, (v));
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#define stbi__wptag(data, s) stbi__wpng4(data, s[0], s[1], s[2], s[3])
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|
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static void stbi__wpcrc(unsigned char **data, int len)
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{
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unsigned int crc = stbi__crc32(*data - len - 4, len + 4);
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stbi__wp32(*data, crc);
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}
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static unsigned char stbi__paeth(int a, int b, int c)
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|
{
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int p = a + b - c, pa = abs(p - a), pb = abs(p - b), pc = abs(p - c);
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if (pa <= pb && pa <= pc) return (unsigned char)a;
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if (pb <= pc) return (unsigned char)b;
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return (unsigned char)c;
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}
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unsigned char *stbi_write_png_to_mem(unsigned char *pixels, int stride_bytes, int x, int y, int n, int *out_len)
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{
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int ctype[5] = {-1, 0, 4, 2, 6};
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unsigned char sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
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unsigned char *out, *o, *filt, *zlib;
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signed char *line_buffer;
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int i, j, k, p, zlen;
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if (stride_bytes == 0)
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stride_bytes = x * n;
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|
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filt = (unsigned char *)malloc((x * n + 1) * y);
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if (!filt) return 0;
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line_buffer = (signed char *)malloc(x * n);
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if (!line_buffer)
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{
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free(filt);
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return 0;
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}
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for (j = 0; j < y; ++j)
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{
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|
static int mapping[] = {0, 1, 2, 3, 4};
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static int firstmap[] = {0, 1, 0, 5, 6};
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int *mymap = j ? mapping : firstmap;
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int best = 0, bestval = 0x7fffffff;
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for (p = 0; p < 2; ++p)
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|
{
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for (k = p ? best : 0; k < 5; ++k)
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|
{
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|
int type = mymap[k], est = 0;
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|
unsigned char *z = pixels + stride_bytes * j;
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|
for (i = 0; i < n; ++i)
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switch (type)
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|
{
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|
case 0:
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|
line_buffer[i] = z[i];
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|
break;
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|
case 1:
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|
line_buffer[i] = z[i];
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|
break;
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|
case 2:
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|
line_buffer[i] = z[i] - z[i - stride_bytes];
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|
break;
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|
case 3:
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|
line_buffer[i] = z[i] - (z[i - stride_bytes] >> 1);
|
|
break;
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|
case 4:
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|
line_buffer[i] = (signed char)(z[i] - stbi__paeth(0, z[i - stride_bytes], 0));
|
|
break;
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|
case 5:
|
|
line_buffer[i] = z[i];
|
|
break;
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|
case 6:
|
|
line_buffer[i] = z[i];
|
|
break;
|
|
}
|
|
for (i = n; i < x * n; ++i)
|
|
{
|
|
switch (type)
|
|
{
|
|
case 0:
|
|
line_buffer[i] = z[i];
|
|
break;
|
|
case 1:
|
|
line_buffer[i] = z[i] - z[i - n];
|
|
break;
|
|
case 2:
|
|
line_buffer[i] = z[i] - z[i - stride_bytes];
|
|
break;
|
|
case 3:
|
|
line_buffer[i] = z[i] - ((z[i - n] + z[i - stride_bytes]) >> 1);
|
|
break;
|
|
case 4:
|
|
line_buffer[i] = z[i] - stbi__paeth(z[i - n], z[i - stride_bytes], z[i - stride_bytes - n]);
|
|
break;
|
|
case 5:
|
|
line_buffer[i] = z[i] - (z[i - n] >> 1);
|
|
break;
|
|
case 6:
|
|
line_buffer[i] = z[i] - stbi__paeth(z[i - n], 0, 0);
|
|
break;
|
|
}
|
|
}
|
|
if (p) break;
|
|
for (i = 0; i < x * n; ++i)
|
|
est += abs((signed char)line_buffer[i]);
|
|
if (est < bestval)
|
|
{
|
|
bestval = est;
|
|
best = k;
|
|
}
|
|
}
|
|
}
|
|
// when we get here, best contains the filter type, and line_buffer contains the data
|
|
filt[j * (x * n + 1)] = (unsigned char)best;
|
|
memcpy(filt + j * (x * n + 1) + 1, line_buffer, x * n);
|
|
}
|
|
free(line_buffer);
|
|
zlib = stbi_zlib_compress(filt, y * (x * n + 1), &zlen, 8); // increase 8 to get smaller but use more memory
|
|
free(filt);
|
|
if (!zlib) return 0;
|
|
|
|
// each tag requires 12 bytes of overhead
|
|
out = (unsigned char *)malloc(8 + 12 + 13 + 12 + zlen + 12);
|
|
if (!out) return 0;
|
|
*out_len = 8 + 12 + 13 + 12 + zlen + 12;
|
|
|
|
o = out;
|
|
memcpy(o, sig, 8);
|
|
o += 8;
|
|
stbi__wp32(o, 13); // header length
|
|
stbi__wptag(o, "IHDR");
|
|
stbi__wp32(o, x);
|
|
stbi__wp32(o, y);
|
|
*o++ = 8;
|
|
*o++ = (unsigned char)ctype[n];
|
|
*o++ = 0;
|
|
*o++ = 0;
|
|
*o++ = 0;
|
|
stbi__wpcrc(&o, 13);
|
|
|
|
stbi__wp32(o, zlen);
|
|
stbi__wptag(o, "IDAT");
|
|
memcpy(o, zlib, zlen);
|
|
o += zlen;
|
|
free(zlib);
|
|
stbi__wpcrc(&o, zlen);
|
|
|
|
stbi__wp32(o, 0);
|
|
stbi__wptag(o, "IEND");
|
|
stbi__wpcrc(&o, 0);
|
|
|
|
assert(o == out + *out_len);
|
|
|
|
return out;
|
|
}
|
|
|
|
int stbi_write_png(char const *filename, int x, int y, int comp, const void *data, int stride_bytes)
|
|
{
|
|
FILE *f;
|
|
int len;
|
|
unsigned char *png = stbi_write_png_to_mem((unsigned char *)data, stride_bytes, x, y, comp, &len);
|
|
if (!png) return 0;
|
|
f = fopen(filename, "wb");
|
|
if (!f)
|
|
{
|
|
free(png);
|
|
return 0;
|
|
}
|
|
fwrite(png, 1, len, f);
|
|
fclose(f);
|
|
free(png);
|
|
return 1;
|
|
}
|
|
#endif // STB_IMAGE_WRITE_IMPLEMENTATION
|
|
|
|
/* Revision history
|
|
|
|
0.92 (2010-08-01)
|
|
casts to unsigned char to fix warnings
|
|
0.91 (2010-07-17)
|
|
first public release
|
|
0.90 first internal release
|
|
*/
|