From 0894de77f949f37c878f12517dc3a7fea7572726 Mon Sep 17 00:00:00 2001 From: johan bowald Date: Sun, 1 Apr 2018 13:31:09 +0200 Subject: [PATCH] added stb_image_write.h --- stb_image_write.h | 1831 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1831 insertions(+) create mode 100644 stb_image_write.h diff --git a/stb_image_write.h b/stb_image_write.h new file mode 100644 index 0000000..17c68a2 --- /dev/null +++ b/stb_image_write.h @@ -0,0 +1,1831 @@ +/* stb_image_write - v1.09 - public domain - +http://nothings.org/stb/stb_image_write.h writes out PNG/BMP/TGA/JPEG/HDR images +to C stdio - Sean Barrett 2010-2015 no warranty implied; use at your own risk + + Before #including, + + #define STB_IMAGE_WRITE_IMPLEMENTATION + + in the file that you want to have the implementation. + + Will probably not work correctly with strict-aliasing optimizations. + + If using a modern Microsoft Compiler, non-safe versions of CRT calls may +cause compilation warnings or even errors. To avoid this, also before +#including, + + #define STBI_MSC_SECURE_CRT + +ABOUT: + + This header file is a library for writing images to C stdio. It could be + adapted to write to memory or a general streaming interface; let me know. + + The PNG output is not optimal; it is 20-50% larger than the file + written by a decent optimizing implementation; though providing a custom + zlib compress function (see STBIW_ZLIB_COMPRESS) can mitigate that. + This library is designed for source code compactness and simplicity, + not optimal image file size or run-time performance. + +BUILDING: + + You can #define STBIW_ASSERT(x) before the #include to avoid using assert.h. + You can #define STBIW_MALLOC(), STBIW_REALLOC(), and STBIW_FREE() to replace + malloc,realloc,free. + You can #define STBIW_MEMMOVE() to replace memmove() + You can #define STBIW_ZLIB_COMPRESS to use a custom zlib-style compress +function for PNG compression (instead of the builtin one), it must have the +following signature: unsigned char * my_compress(unsigned char *data, int +data_len, int *out_len, int quality); The returned data will be freed with +STBIW_FREE() (free() by default), so it must be heap allocated with +STBIW_MALLOC() (malloc() by default), + +USAGE: + + There are five functions, one for each image file format: + + int stbi_write_png(char const *filename, int w, int h, int comp, const void +*data, int stride_in_bytes); int stbi_write_bmp(char const *filename, int w, int +h, int comp, const void *data); int stbi_write_tga(char const *filename, int w, +int h, int comp, const void *data); int stbi_write_jpg(char const *filename, int +w, int h, int comp, const void *data, int quality); int stbi_write_hdr(char +const *filename, int w, int h, int comp, const float *data); + + void stbi_flip_vertically_on_write(int flag); // flag is non-zero to flip +data vertically + + There are also five equivalent functions that use an arbitrary write +function. You are expected to open/close your file-equivalent before and after +calling these: + + int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int +h, int comp, const void *data, int stride_in_bytes); int +stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int +comp, const void *data); int stbi_write_tga_to_func(stbi_write_func *func, void +*context, int w, int h, int comp, const void *data); int +stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int +comp, const float *data); int stbi_write_jpg_to_func(stbi_write_func *func, void +*context, int x, int y, int comp, const void *data, int quality); + + where the callback is: + void stbi_write_func(void *context, void *data, int size); + + You can configure it with these global variables: + int stbi_write_tga_with_rle; // defaults to true; set to 0 to +disable RLE int stbi_write_png_compression_level; // defaults to 8; set to +higher for more compression int stbi_write_force_png_filter; // defaults +to -1; set to 0..5 to force a filter mode + + + You can define STBI_WRITE_NO_STDIO to disable the file variant of these + functions, so the library will not use stdio.h at all. However, this will + also disable HDR writing, because it requires stdio for formatted output. + + Each function returns 0 on failure and non-0 on success. + + The functions create an image file defined by the parameters. The image + is a rectangle of pixels stored from left-to-right, top-to-bottom. + Each pixel contains 'comp' channels of data stored interleaved with 8-bits + per channel, in the following order: 1=Y, 2=YA, 3=RGB, 4=RGBA. (Y is + monochrome color.) The rectangle is 'w' pixels wide and 'h' pixels tall. + The *data pointer points to the first byte of the top-left-most pixel. + For PNG, "stride_in_bytes" is the distance in bytes from the first byte of + a row of pixels to the first byte of the next row of pixels. + + PNG creates output files with the same number of components as the input. + The BMP format expands Y to RGB in the file format and does not + output alpha. + + PNG supports writing rectangles of data even when the bytes storing rows of + data are not consecutive in memory (e.g. sub-rectangles of a larger image), + by supplying the stride between the beginning of adjacent rows. The other + formats do not. (Thus you cannot write a native-format BMP through the BMP + writer, both because it is in BGR order and because it may have padding + at the end of the line.) + + PNG allows you to set the deflate compression level by setting the global + variable 'stbi_write_png_compression_level' (it defaults to 8). + + HDR expects linear float data. Since the format is always 32-bit rgb(e) + data, alpha (if provided) is discarded, and for monochrome data it is + replicated across all three channels. + + TGA supports RLE or non-RLE compressed data. To use non-RLE-compressed + data, set the global variable 'stbi_write_tga_with_rle' to 0. + + + JPEG does ignore alpha channels in input data; quality is between 1 and 100. + Higher quality looks better but results in a bigger image. + JPEG baseline (no JPEG progressive). + +CREDITS: + + + Sean Barrett - PNG/BMP/TGA + Baldur Karlsson - HDR + Jean-Sebastien Guay - TGA monochrome + Tim Kelsey - misc enhancements + Alan Hickman - TGA RLE + Emmanuel Julien - initial file IO callback implementation + Jon Olick - original jo_jpeg.cpp code + Daniel Gibson - integrate JPEG, allow external zlib + Aarni Koskela - allow choosing PNG filter + + bugfixes: + github:Chribba + Guillaume Chereau + github:jry2 + github:romigrou + Sergio Gonzalez + Jonas Karlsson + Filip Wasil + Thatcher Ulrich + github:poppolopoppo + Patrick Boettcher + github:xeekworx + Cap Petschulat + Simon Rodriguez + Ivan Tikhonov + github:ignotion + Adam Schackart + +LICENSE + + See end of file for license information. + +*/ + +#ifndef INCLUDE_STB_IMAGE_WRITE_H +#define INCLUDE_STB_IMAGE_WRITE_H + +// if STB_IMAGE_WRITE_STATIC causes problems, try defining STBIWDEF to 'inline' +// or 'static inline' +#ifndef STBIWDEF +#ifdef STB_IMAGE_WRITE_STATIC +#define STBIWDEF static +#else +#ifdef __cplusplus +#define STBIWDEF extern "C" +#else +#define STBIWDEF extern +#endif +#endif +#endif + +#ifndef STB_IMAGE_WRITE_STATIC // C++ forbids static forward declarations +extern int stbi_write_tga_with_rle; +extern int stbi_write_png_compression_level; +extern int stbi_write_force_png_filter; +#endif + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF int stbi_write_png(char const *filename, int w, int h, int comp, + const void *data, int stride_in_bytes); +STBIWDEF int stbi_write_bmp(char const *filename, int w, int h, int comp, + const void *data); +STBIWDEF int stbi_write_tga(char const *filename, int w, int h, int comp, + const void *data); +STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, + const float *data); +STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, + const void *data, int quality); +#endif + +typedef void stbi_write_func(void *context, void *data, int size); + +STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, + int h, int comp, const void *data, + int stride_in_bytes); +STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, + int h, int comp, const void *data); +STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, + int h, int comp, const void *data); +STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, + int h, int comp, const float *data); +STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, + int y, int comp, const void *data, + int quality); + +STBIWDEF void stbi_flip_vertically_on_write(int flip_boolean); + +#endif // INCLUDE_STB_IMAGE_WRITE_H + +#ifdef STB_IMAGE_WRITE_IMPLEMENTATION + +#ifdef _WIN32 +#ifndef _CRT_SECURE_NO_WARNINGS +#define _CRT_SECURE_NO_WARNINGS +#endif +#ifndef _CRT_NONSTDC_NO_DEPRECATE +#define _CRT_NONSTDC_NO_DEPRECATE +#endif +#endif + +#ifndef STBI_WRITE_NO_STDIO +#include +#endif // STBI_WRITE_NO_STDIO + +#include +#include +#include +#include + +#if defined(STBIW_MALLOC) && defined(STBIW_FREE) && \ + (defined(STBIW_REALLOC) || defined(STBIW_REALLOC_SIZED)) +// ok +#elif !defined(STBIW_MALLOC) && !defined(STBIW_FREE) && \ + !defined(STBIW_REALLOC) && !defined(STBIW_REALLOC_SIZED) +// ok +#else +#error \ + "Must define all or none of STBIW_MALLOC, STBIW_FREE, and STBIW_REALLOC (or STBIW_REALLOC_SIZED)." +#endif + +#ifndef STBIW_MALLOC +#define STBIW_MALLOC(sz) malloc(sz) +#define STBIW_REALLOC(p, newsz) realloc(p, newsz) +#define STBIW_FREE(p) free(p) +#endif + +#ifndef STBIW_REALLOC_SIZED +#define STBIW_REALLOC_SIZED(p, oldsz, newsz) STBIW_REALLOC(p, newsz) +#endif + +#ifndef STBIW_MEMMOVE +#define STBIW_MEMMOVE(a, b, sz) memmove(a, b, sz) +#endif + +#ifndef STBIW_ASSERT +#include +#define STBIW_ASSERT(x) assert(x) +#endif + +#define STBIW_UCHAR(x) (unsigned char)((x)&0xff) + +#ifdef STB_IMAGE_WRITE_STATIC +static int stbi__flip_vertically_on_write = 0; +static int stbi_write_png_compression_level = 8; +static int stbi_write_tga_with_rle = 1; +static int stbi_write_force_png_filter = -1; +#else +int stbi_write_png_compression_level = 8; +int stbi__flip_vertically_on_write = 0; +int stbi_write_tga_with_rle = 1; +int stbi_write_force_png_filter = -1; +#endif + +STBIWDEF void stbi_flip_vertically_on_write(int flag) { + stbi__flip_vertically_on_write = flag; +} + +typedef struct { + stbi_write_func *func; + void *context; +} stbi__write_context; + +// initialize a callback-based context +static void stbi__start_write_callbacks(stbi__write_context *s, + stbi_write_func *c, void *context) { + s->func = c; + s->context = context; +} + +#ifndef STBI_WRITE_NO_STDIO + +static void stbi__stdio_write(void *context, void *data, int size) { + fwrite(data, 1, size, (FILE *)context); +} + +static int stbi__start_write_file(stbi__write_context *s, + const char *filename) { + FILE *f; +#ifdef STBI_MSC_SECURE_CRT + if (fopen_s(&f, filename, "wb")) f = NULL; +#else + f = fopen(filename, "wb"); +#endif + stbi__start_write_callbacks(s, stbi__stdio_write, (void *)f); + return f != NULL; +} + +static void stbi__end_write_file(stbi__write_context *s) { + fclose((FILE *)s->context); +} + +#endif // !STBI_WRITE_NO_STDIO + +typedef unsigned int stbiw_uint32; +typedef int stb_image_write_test[sizeof(stbiw_uint32) == 4 ? 1 : -1]; + +static void stbiw__writefv(stbi__write_context *s, const char *fmt, va_list v) { + while (*fmt) { + switch (*fmt++) { + case ' ': + break; + case '1': { + unsigned char x = STBIW_UCHAR(va_arg(v, int)); + s->func(s->context, &x, 1); + break; + } + case '2': { + int x = va_arg(v, int); + unsigned char b[2]; + b[0] = STBIW_UCHAR(x); + b[1] = STBIW_UCHAR(x >> 8); + s->func(s->context, b, 2); + break; + } + case '4': { + stbiw_uint32 x = va_arg(v, int); + unsigned char b[4]; + b[0] = STBIW_UCHAR(x); + b[1] = STBIW_UCHAR(x >> 8); + b[2] = STBIW_UCHAR(x >> 16); + b[3] = STBIW_UCHAR(x >> 24); + s->func(s->context, b, 4); + break; + } + default: + STBIW_ASSERT(0); + return; + } + } +} + +static void stbiw__writef(stbi__write_context *s, const char *fmt, ...) { + va_list v; + va_start(v, fmt); + stbiw__writefv(s, fmt, v); + va_end(v); +} + +static void stbiw__putc(stbi__write_context *s, unsigned char c) { + s->func(s->context, &c, 1); +} + +static void stbiw__write3(stbi__write_context *s, unsigned char a, + unsigned char b, unsigned char c) { + unsigned char arr[3]; + arr[0] = a, arr[1] = b, arr[2] = c; + s->func(s->context, arr, 3); +} + +static void stbiw__write_pixel(stbi__write_context *s, int rgb_dir, int comp, + int write_alpha, int expand_mono, + unsigned char *d) { + unsigned char bg[3] = {255, 0, 255}, px[3]; + int k; + + if (write_alpha < 0) s->func(s->context, &d[comp - 1], 1); + + switch (comp) { + case 2: // 2 pixels = mono + alpha, alpha is written separately, so same as + // 1-channel case + case 1: + if (expand_mono) + stbiw__write3(s, d[0], d[0], d[0]); // monochrome bmp + else + s->func(s->context, d, 1); // monochrome TGA + break; + case 4: + if (!write_alpha) { + // composite against pink background + for (k = 0; k < 3; ++k) px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255; + stbiw__write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]); + break; + } + /* FALLTHROUGH */ + case 3: + stbiw__write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]); + break; + } + if (write_alpha > 0) s->func(s->context, &d[comp - 1], 1); +} + +static void stbiw__write_pixels(stbi__write_context *s, int rgb_dir, int vdir, + int x, int y, int comp, void *data, + int write_alpha, int scanline_pad, + int expand_mono) { + stbiw_uint32 zero = 0; + int i, j, j_end; + + if (y <= 0) return; + + if (stbi__flip_vertically_on_write) vdir *= -1; + + if (vdir < 0) + j_end = -1, j = y - 1; + else + j_end = y, j = 0; + + for (; j != j_end; j += vdir) { + for (i = 0; i < x; ++i) { + unsigned char *d = (unsigned char *)data + (j * x + i) * comp; + stbiw__write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d); + } + s->func(s->context, &zero, scanline_pad); + } +} + +static int stbiw__outfile(stbi__write_context *s, int rgb_dir, int vdir, int x, + int y, int comp, int expand_mono, void *data, + int alpha, int pad, const char *fmt, ...) { + if (y < 0 || x < 0) { + return 0; + } else { + va_list v; + va_start(v, fmt); + stbiw__writefv(s, fmt, v); + va_end(v); + stbiw__write_pixels(s, rgb_dir, vdir, x, y, comp, data, alpha, pad, + expand_mono); + return 1; + } +} + +static int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp, + const void *data) { + int pad = (-x * 3) & 3; + return stbiw__outfile(s, -1, -1, x, y, comp, 1, (void *)data, 0, pad, + "11 4 22 4" + "4 44 22 444444", + 'B', 'M', 14 + 40 + (x * 3 + pad) * y, 0, 0, + 14 + 40, // file header + 40, x, y, 1, 24, 0, 0, 0, 0, 0, 0); // bitmap header +} + +STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, + int y, int comp, const void *data) { + stbi__write_context s; + stbi__start_write_callbacks(&s, func, context); + return stbi_write_bmp_core(&s, x, y, comp, data); +} + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, + const void *data) { + stbi__write_context s; + if (stbi__start_write_file(&s, filename)) { + int r = stbi_write_bmp_core(&s, x, y, comp, data); + stbi__end_write_file(&s); + return r; + } else + return 0; +} +#endif //! STBI_WRITE_NO_STDIO + +static int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp, + void *data) { + int has_alpha = (comp == 2 || comp == 4); + int colorbytes = has_alpha ? comp - 1 : comp; + int format = + colorbytes < 2 + ? 3 + : 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3 + + if (y < 0 || x < 0) return 0; + + if (!stbi_write_tga_with_rle) { + return stbiw__outfile(s, -1, -1, x, y, comp, 0, (void *)data, has_alpha, 0, + "111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y, + (colorbytes + has_alpha) * 8, has_alpha * 8); + } else { + int i, j, k; + int jend, jdir; + + stbiw__writef(s, "111 221 2222 11", 0, 0, format + 8, 0, 0, 0, 0, 0, x, y, + (colorbytes + has_alpha) * 8, has_alpha * 8); + + if (stbi__flip_vertically_on_write) { + j = 0; + jend = y; + jdir = 1; + } else { + j = y - 1; + jend = -1; + jdir = -1; + } + for (; j != jend; j += jdir) { + unsigned char *row = (unsigned char *)data + j * x * comp; + int len; + + for (i = 0; i < x; i += len) { + unsigned char *begin = row + i * comp; + int diff = 1; + len = 1; + + if (i < x - 1) { + ++len; + diff = memcmp(begin, row + (i + 1) * comp, comp); + if (diff) { + const unsigned char *prev = begin; + for (k = i + 2; k < x && len < 128; ++k) { + if (memcmp(prev, row + k * comp, comp)) { + prev += comp; + ++len; + } else { + --len; + break; + } + } + } else { + for (k = i + 2; k < x && len < 128; ++k) { + if (!memcmp(begin, row + k * comp, comp)) { + ++len; + } else { + break; + } + } + } + } + + if (diff) { + unsigned char header = STBIW_UCHAR(len - 1); + s->func(s->context, &header, 1); + for (k = 0; k < len; ++k) { + stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp); + } + } else { + unsigned char header = STBIW_UCHAR(len - 129); + s->func(s->context, &header, 1); + stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin); + } + } + } + } + return 1; +} + +STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, + int y, int comp, const void *data) { + stbi__write_context s; + stbi__start_write_callbacks(&s, func, context); + return stbi_write_tga_core(&s, x, y, comp, (void *)data); +} + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, + const void *data) { + stbi__write_context s; + if (stbi__start_write_file(&s, filename)) { + int r = stbi_write_tga_core(&s, x, y, comp, (void *)data); + stbi__end_write_file(&s); + return r; + } else + return 0; +} +#endif + +// ************************************************************************************************* +// Radiance RGBE HDR writer +// by Baldur Karlsson + +#define stbiw__max(a, b) ((a) > (b) ? (a) : (b)) + +void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear) { + int exponent; + float maxcomp = stbiw__max(linear[0], stbiw__max(linear[1], linear[2])); + + if (maxcomp < 1e-32f) { + rgbe[0] = rgbe[1] = rgbe[2] = rgbe[3] = 0; + } else { + float 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); + } +} + +void stbiw__write_run_data(stbi__write_context *s, int length, + unsigned char databyte) { + unsigned char lengthbyte = STBIW_UCHAR(length + 128); + STBIW_ASSERT(length + 128 <= 255); + s->func(s->context, &lengthbyte, 1); + s->func(s->context, &databyte, 1); +} + +void stbiw__write_dump_data(stbi__write_context *s, int length, + unsigned char *data) { + unsigned char lengthbyte = STBIW_UCHAR(length); + STBIW_ASSERT( + length <= + 128); // inconsistent with spec but consistent with official code + s->func(s->context, &lengthbyte, 1); + s->func(s->context, data, length); +} + +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 = (unsigned char *)STBIW_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); + +#ifdef STBI_MSC_SECURE_CRT + len = sprintf_s( + buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x); +#else + len = sprintf(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", + y, x); +#endif + 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) * x); + STBIW_FREE(scratch); + return 1; + } +} + +STBIWDEF 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); +} + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF 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; +} +#endif // STBI_WRITE_NO_STDIO + +////////////////////////////////////////////////////////////////////////////// +// +// PNG writer +// + +#ifndef STBIW_ZLIB_COMPRESS +// stretchy buffer; stbiw__sbpush() == vector<>::push_back() -- stbiw__sbcount() +// == vector<>::size() +#define stbiw__sbraw(a) ((int *)(a)-2) +#define stbiw__sbm(a) stbiw__sbraw(a)[0] +#define stbiw__sbn(a) stbiw__sbraw(a)[1] + +#define stbiw__sbneedgrow(a, n) ((a) == 0 || stbiw__sbn(a) + n >= stbiw__sbm(a)) +#define stbiw__sbmaybegrow(a, n) \ + (stbiw__sbneedgrow(a, (n)) ? stbiw__sbgrow(a, n) : 0) +#define stbiw__sbgrow(a, n) stbiw__sbgrowf((void **)&(a), (n), sizeof(*(a))) + +#define stbiw__sbpush(a, v) \ + (stbiw__sbmaybegrow(a, 1), (a)[stbiw__sbn(a)++] = (v)) +#define stbiw__sbcount(a) ((a) ? stbiw__sbn(a) : 0) +#define stbiw__sbfree(a) ((a) ? STBIW_FREE(stbiw__sbraw(a)), 0 : 0) + +static void *stbiw__sbgrowf(void **arr, int increment, int itemsize) { + int m = *arr ? 2 * stbiw__sbm(*arr) + increment : increment + 1; + void *p = STBIW_REALLOC_SIZED( + *arr ? stbiw__sbraw(*arr) : 0, + *arr ? (stbiw__sbm(*arr) * itemsize + sizeof(int) * 2) : 0, + itemsize * m + sizeof(int) * 2); + STBIW_ASSERT(p); + if (p) { + if (!*arr) ((int *)p)[1] = 0; + *arr = (void *)((int *)p + 2); + stbiw__sbm(*arr) = m; + } + return *arr; +} + +static unsigned char *stbiw__zlib_flushf(unsigned char *data, + unsigned int *bitbuffer, + int *bitcount) { + while (*bitcount >= 8) { + stbiw__sbpush(data, STBIW_UCHAR(*bitbuffer)); + *bitbuffer >>= 8; + *bitcount -= 8; + } + return data; +} + +static int stbiw__zlib_bitrev(int code, int codebits) { + int res = 0; + while (codebits--) { + res = (res << 1) | (code & 1); + code >>= 1; + } + return res; +} + +static unsigned int stbiw__zlib_countm(unsigned char *a, unsigned char *b, + int limit) { + int i; + for (i = 0; i < limit && i < 258; ++i) + if (a[i] != b[i]) break; + return i; +} + +static unsigned int stbiw__zhash(unsigned char *data) { + stbiw_uint32 hash = data[0] + (data[1] << 8) + (data[2] << 16); + hash ^= hash << 3; + hash += hash >> 5; + hash ^= hash << 4; + hash += hash >> 17; + hash ^= hash << 25; + hash += hash >> 6; + return hash; +} + +#define stbiw__zlib_flush() (out = stbiw__zlib_flushf(out, &bitbuf, &bitcount)) +#define stbiw__zlib_add(code, codebits) \ + (bitbuf |= (code) << bitcount, bitcount += (codebits), stbiw__zlib_flush()) +#define stbiw__zlib_huffa(b, c) stbiw__zlib_add(stbiw__zlib_bitrev(b, c), c) +// default huffman tables +#define stbiw__zlib_huff1(n) stbiw__zlib_huffa(0x30 + (n), 8) +#define stbiw__zlib_huff2(n) stbiw__zlib_huffa(0x190 + (n)-144, 9) +#define stbiw__zlib_huff3(n) stbiw__zlib_huffa(0 + (n)-256, 7) +#define stbiw__zlib_huff4(n) stbiw__zlib_huffa(0xc0 + (n)-280, 8) +#define stbiw__zlib_huff(n) \ + ((n) <= 143 ? stbiw__zlib_huff1(n) \ + : (n) <= 255 ? stbiw__zlib_huff2(n) \ + : (n) <= 279 ? stbiw__zlib_huff3(n) \ + : stbiw__zlib_huff4(n)) +#define stbiw__zlib_huffb(n) \ + ((n) <= 143 ? stbiw__zlib_huff1(n) : stbiw__zlib_huff2(n)) + +#define stbiw__ZHASH 16384 + +#endif // STBIW_ZLIB_COMPRESS + +unsigned char *stbi_zlib_compress(unsigned char *data, int data_len, + int *out_len, int quality) { +#ifdef STBIW_ZLIB_COMPRESS + // user provided a zlib compress implementation, use that + return STBIW_ZLIB_COMPRESS(data, data_len, out_len, quality); +#else // use builtin + 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}; + 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}; + 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}; + 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}; + unsigned int bitbuf = 0; + int i, j, bitcount = 0; + unsigned char *out = NULL; + unsigned char ***hash_table = + (unsigned char ***)STBIW_MALLOC(stbiw__ZHASH * sizeof(char **)); + if (hash_table == NULL) return NULL; + if (quality < 5) quality = 5; + + stbiw__sbpush(out, 0x78); // DEFLATE 32K window + stbiw__sbpush(out, 0x5e); // FLEVEL = 1 + stbiw__zlib_add(1, 1); // BFINAL = 1 + stbiw__zlib_add(1, 2); // BTYPE = 1 -- fixed huffman + + for (i = 0; i < stbiw__ZHASH; ++i) hash_table[i] = NULL; + + i = 0; + while (i < data_len - 3) { + // hash next 3 bytes of data to be compressed + int h = stbiw__zhash(data + i) & (stbiw__ZHASH - 1), best = 3; + unsigned char *bestloc = 0; + unsigned char **hlist = hash_table[h]; + int n = stbiw__sbcount(hlist); + for (j = 0; j < n; ++j) { + if (hlist[j] - data > i - 32768) { // if entry lies within window + int d = stbiw__zlib_countm(hlist[j], data + i, data_len - i); + if (d >= best) best = d, bestloc = hlist[j]; + } + } + // when hash table entry is too long, delete half the entries + if (hash_table[h] && stbiw__sbn(hash_table[h]) == 2 * quality) { + STBIW_MEMMOVE(hash_table[h], hash_table[h] + quality, + sizeof(hash_table[h][0]) * quality); + stbiw__sbn(hash_table[h]) = quality; + } + stbiw__sbpush(hash_table[h], data + i); + + if (bestloc) { + // "lazy matching" - check match at *next* byte, and if it's better, do + // cur byte as literal + h = stbiw__zhash(data + i + 1) & (stbiw__ZHASH - 1); + hlist = hash_table[h]; + n = stbiw__sbcount(hlist); + for (j = 0; j < n; ++j) { + if (hlist[j] - data > i - 32767) { + int e = stbiw__zlib_countm(hlist[j], data + i + 1, data_len - i - 1); + if (e > best) { // if next match is better, bail on current match + bestloc = NULL; + break; + } + } + } + } + + if (bestloc) { + int d = (int)(data + i - bestloc); // distance back + STBIW_ASSERT(d <= 32767 && best <= 258); + for (j = 0; best > lengthc[j + 1] - 1; ++j) + ; + stbiw__zlib_huff(j + 257); + if (lengtheb[j]) stbiw__zlib_add(best - lengthc[j], lengtheb[j]); + for (j = 0; d > distc[j + 1] - 1; ++j) + ; + stbiw__zlib_add(stbiw__zlib_bitrev(j, 5), 5); + if (disteb[j]) stbiw__zlib_add(d - distc[j], disteb[j]); + i += best; + } else { + stbiw__zlib_huffb(data[i]); + ++i; + } + } + // write out final bytes + for (; i < data_len; ++i) stbiw__zlib_huffb(data[i]); + stbiw__zlib_huff(256); // end of block + // pad with 0 bits to byte boundary + while (bitcount) stbiw__zlib_add(0, 1); + + for (i = 0; i < stbiw__ZHASH; ++i) (void)stbiw__sbfree(hash_table[i]); + STBIW_FREE(hash_table); + + { + // compute adler32 on input + unsigned int s1 = 1, s2 = 0; + int blocklen = (int)(data_len % 5552); + j = 0; + while (j < data_len) { + for (i = 0; i < blocklen; ++i) s1 += data[j + i], s2 += s1; + s1 %= 65521, s2 %= 65521; + j += blocklen; + blocklen = 5552; + } + stbiw__sbpush(out, STBIW_UCHAR(s2 >> 8)); + stbiw__sbpush(out, STBIW_UCHAR(s2)); + stbiw__sbpush(out, STBIW_UCHAR(s1 >> 8)); + stbiw__sbpush(out, STBIW_UCHAR(s1)); + } + *out_len = stbiw__sbn(out); + // make returned pointer freeable + STBIW_MEMMOVE(stbiw__sbraw(out), out, *out_len); + return (unsigned char *)stbiw__sbraw(out); +#endif // STBIW_ZLIB_COMPRESS +} + +static unsigned int stbiw__crc32(unsigned char *buffer, int len) { + static unsigned int crc_table[256] = { + 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, + 0xE963A535, 0x9E6495A3, 0x0eDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, + 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2, + 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, + 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, + 0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, + 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C, + 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, + 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, + 0xCFBA9599, 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, + 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190, 0x01DB7106, + 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, + 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, + 0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, + 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950, + 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, + 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, + 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, + 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA, + 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, + 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, + 0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, + 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 0xE3630B12, 0x94643B84, + 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, + 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, + 0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, + 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E, + 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, + 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, + 0x316E8EEF, 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, + 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE, 0xB2BD0B28, + 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, + 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, + 0x72076785, 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, + 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242, + 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, + 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, + 0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, + 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC, + 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, + 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, + 0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, + 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D}; + + unsigned int crc = ~0u; + int i; + for (i = 0; i < len; ++i) + crc = (crc >> 8) ^ crc_table[buffer[i] ^ (crc & 0xff)]; + return ~crc; +} + +#define stbiw__wpng4(o, a, b, c, d) \ + ((o)[0] = STBIW_UCHAR(a), (o)[1] = STBIW_UCHAR(b), (o)[2] = STBIW_UCHAR(c), \ + (o)[3] = STBIW_UCHAR(d), (o) += 4) +#define stbiw__wp32(data, v) \ + stbiw__wpng4(data, (v) >> 24, (v) >> 16, (v) >> 8, (v)); +#define stbiw__wptag(data, s) stbiw__wpng4(data, s[0], s[1], s[2], s[3]) + +static void stbiw__wpcrc(unsigned char **data, int len) { + unsigned int crc = stbiw__crc32(*data - len - 4, len + 4); + stbiw__wp32(*data, crc); +} + +static unsigned char stbiw__paeth(int a, int b, int c) { + int p = a + b - c, pa = abs(p - a), pb = abs(p - b), pc = abs(p - c); + if (pa <= pb && pa <= pc) return STBIW_UCHAR(a); + if (pb <= pc) return STBIW_UCHAR(b); + return STBIW_UCHAR(c); +} + +// @OPTIMIZE: provide an option that always forces left-predict or paeth predict +static void stbiw__encode_png_line(unsigned char *pixels, int stride_bytes, + int width, int height, int y, int n, + int filter_type, signed char *line_buffer) { + static int mapping[] = {0, 1, 2, 3, 4}; + static int firstmap[] = {0, 1, 0, 5, 6}; + int *mymap = (y != 0) ? mapping : firstmap; + int i; + int type = mymap[filter_type]; + unsigned char *z = + pixels + + stride_bytes * (stbi__flip_vertically_on_write ? height - 1 - y : y); + int signed_stride = + stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes; + for (i = 0; i < n; ++i) { + switch (type) { + case 0: + line_buffer[i] = z[i]; + break; + case 1: + line_buffer[i] = z[i]; + break; + case 2: + line_buffer[i] = z[i] - z[i - signed_stride]; + break; + case 3: + line_buffer[i] = z[i] - (z[i - signed_stride] >> 1); + break; + case 4: + line_buffer[i] = + (signed char)(z[i] - stbiw__paeth(0, z[i - signed_stride], 0)); + break; + case 5: + line_buffer[i] = z[i]; + break; + case 6: + line_buffer[i] = z[i]; + break; + } + } + for (i = n; i < width * 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 - signed_stride]; + break; + case 3: + line_buffer[i] = z[i] - ((z[i - n] + z[i - signed_stride]) >> 1); + break; + case 4: + line_buffer[i] = z[i] - stbiw__paeth(z[i - n], z[i - signed_stride], + z[i - signed_stride - n]); + break; + case 5: + line_buffer[i] = z[i] - (z[i - n] >> 1); + break; + case 6: + line_buffer[i] = z[i] - stbiw__paeth(z[i - n], 0, 0); + break; + } + } +} + +unsigned char *stbi_write_png_to_mem(unsigned char *pixels, int stride_bytes, + int x, int y, int n, int *out_len) { + int force_filter = stbi_write_force_png_filter; + int ctype[5] = {-1, 0, 4, 2, 6}; + unsigned char sig[8] = {137, 80, 78, 71, 13, 10, 26, 10}; + unsigned char *out, *o, *filt, *zlib; + signed char *line_buffer; + int j, zlen; + + if (stride_bytes == 0) stride_bytes = x * n; + + if (force_filter >= 5) { + force_filter = -1; + } + + filt = (unsigned char *)STBIW_MALLOC((x * n + 1) * y); + if (!filt) return 0; + line_buffer = (signed char *)STBIW_MALLOC(x * n); + if (!line_buffer) { + STBIW_FREE(filt); + return 0; + } + for (j = 0; j < y; ++j) { + int filter_type; + if (force_filter > -1) { + filter_type = force_filter; + stbiw__encode_png_line(pixels, stride_bytes, x, y, j, n, force_filter, + line_buffer); + } else { // Estimate the best filter by running through all of them: + int best_filter = 0, best_filter_val = 0x7fffffff, est, i; + for (filter_type = 0; filter_type < 5; filter_type++) { + stbiw__encode_png_line(pixels, stride_bytes, x, y, j, n, filter_type, + line_buffer); + + // Estimate the entropy of the line using this filter; the less, the + // better. + est = 0; + for (i = 0; i < x * n; ++i) { + est += abs((signed char)line_buffer[i]); + } + if (est < best_filter_val) { + best_filter_val = est; + best_filter = filter_type; + } + } + if (filter_type != best_filter) { // If the last iteration already got us + // the best filter, don't redo it + stbiw__encode_png_line(pixels, stride_bytes, x, y, j, n, best_filter, + line_buffer); + filter_type = best_filter; + } + } + // when we get here, filter_type contains the filter type, and line_buffer + // contains the data + filt[j * (x * n + 1)] = (unsigned char)filter_type; + STBIW_MEMMOVE(filt + j * (x * n + 1) + 1, line_buffer, x * n); + } + STBIW_FREE(line_buffer); + zlib = stbi_zlib_compress(filt, y * (x * n + 1), &zlen, + stbi_write_png_compression_level); + STBIW_FREE(filt); + if (!zlib) return 0; + + // each tag requires 12 bytes of overhead + out = (unsigned char *)STBIW_MALLOC(8 + 12 + 13 + 12 + zlen + 12); + if (!out) return 0; + *out_len = 8 + 12 + 13 + 12 + zlen + 12; + + o = out; + STBIW_MEMMOVE(o, sig, 8); + o += 8; + stbiw__wp32(o, 13); // header length + stbiw__wptag(o, "IHDR"); + stbiw__wp32(o, x); + stbiw__wp32(o, y); + *o++ = 8; + *o++ = STBIW_UCHAR(ctype[n]); + *o++ = 0; + *o++ = 0; + *o++ = 0; + stbiw__wpcrc(&o, 13); + + stbiw__wp32(o, zlen); + stbiw__wptag(o, "IDAT"); + STBIW_MEMMOVE(o, zlib, zlen); + o += zlen; + STBIW_FREE(zlib); + stbiw__wpcrc(&o, zlen); + + stbiw__wp32(o, 0); + stbiw__wptag(o, "IEND"); + stbiw__wpcrc(&o, 0); + + STBIW_ASSERT(o == out + *out_len); + + return out; +} + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF 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 == NULL) return 0; +#ifdef STBI_MSC_SECURE_CRT + if (fopen_s(&f, filename, "wb")) f = NULL; +#else + f = fopen(filename, "wb"); +#endif + if (!f) { + STBIW_FREE(png); + return 0; + } + fwrite(png, 1, len, f); + fclose(f); + STBIW_FREE(png); + return 1; +} +#endif + +STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int x, + int y, int comp, const void *data, + int stride_bytes) { + int len; + unsigned char *png = stbi_write_png_to_mem((unsigned char *)data, + stride_bytes, x, y, comp, &len); + if (png == NULL) return 0; + func(context, png, len); + STBIW_FREE(png); + return 1; +} + +/* *************************************************************************** + * + * JPEG writer + * + * This is based on Jon Olick's jo_jpeg.cpp: + * public domain Simple, Minimalistic JPEG writer - + * http://www.jonolick.com/code.html + */ + +static const unsigned char stbiw__jpg_ZigZag[] = { + 0, 1, 5, 6, 14, 15, 27, 28, 2, 4, 7, 13, 16, 26, 29, 42, + 3, 8, 12, 17, 25, 30, 41, 43, 9, 11, 18, 24, 31, 40, 44, 53, + 10, 19, 23, 32, 39, 45, 52, 54, 20, 22, 33, 38, 46, 51, 55, 60, + 21, 34, 37, 47, 50, 56, 59, 61, 35, 36, 48, 49, 57, 58, 62, 63}; + +static void stbiw__jpg_writeBits(stbi__write_context *s, int *bitBufP, + int *bitCntP, const unsigned short *bs) { + int bitBuf = *bitBufP, bitCnt = *bitCntP; + bitCnt += bs[1]; + bitBuf |= bs[0] << (24 - bitCnt); + while (bitCnt >= 8) { + unsigned char c = (bitBuf >> 16) & 255; + stbiw__putc(s, c); + if (c == 255) { + stbiw__putc(s, 0); + } + bitBuf <<= 8; + bitCnt -= 8; + } + *bitBufP = bitBuf; + *bitCntP = bitCnt; +} + +static void stbiw__jpg_DCT(float *d0p, float *d1p, float *d2p, float *d3p, + float *d4p, float *d5p, float *d6p, float *d7p) { + float d0 = *d0p, d1 = *d1p, d2 = *d2p, d3 = *d3p, d4 = *d4p, d5 = *d5p, + d6 = *d6p, d7 = *d7p; + float z1, z2, z3, z4, z5, z11, z13; + + float tmp0 = d0 + d7; + float tmp7 = d0 - d7; + float tmp1 = d1 + d6; + float tmp6 = d1 - d6; + float tmp2 = d2 + d5; + float tmp5 = d2 - d5; + float tmp3 = d3 + d4; + float tmp4 = d3 - d4; + + // Even part + float tmp10 = tmp0 + tmp3; // phase 2 + float tmp13 = tmp0 - tmp3; + float tmp11 = tmp1 + tmp2; + float tmp12 = tmp1 - tmp2; + + d0 = tmp10 + tmp11; // phase 3 + d4 = tmp10 - tmp11; + + z1 = (tmp12 + tmp13) * 0.707106781f; // c4 + d2 = tmp13 + z1; // phase 5 + d6 = tmp13 - z1; + + // Odd part + tmp10 = tmp4 + tmp5; // phase 2 + tmp11 = tmp5 + tmp6; + tmp12 = tmp6 + tmp7; + + // The rotator is modified from fig 4-8 to avoid extra negations. + z5 = (tmp10 - tmp12) * 0.382683433f; // c6 + z2 = tmp10 * 0.541196100f + z5; // c2-c6 + z4 = tmp12 * 1.306562965f + z5; // c2+c6 + z3 = tmp11 * 0.707106781f; // c4 + + z11 = tmp7 + z3; // phase 5 + z13 = tmp7 - z3; + + *d5p = z13 + z2; // phase 6 + *d3p = z13 - z2; + *d1p = z11 + z4; + *d7p = z11 - z4; + + *d0p = d0; + *d2p = d2; + *d4p = d4; + *d6p = d6; +} + +static void stbiw__jpg_calcBits(int val, unsigned short bits[2]) { + int tmp1 = val < 0 ? -val : val; + val = val < 0 ? val - 1 : val; + bits[1] = 1; + while (tmp1 >>= 1) { + ++bits[1]; + } + bits[0] = val & ((1 << bits[1]) - 1); +} + +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]}; + int dataOff, i, diff, end0pos; + int DU[64]; + + // DCT rows + for (dataOff = 0; dataOff < 64; dataOff += 8) { + stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff + 1], &CDU[dataOff + 2], + &CDU[dataOff + 3], &CDU[dataOff + 4], &CDU[dataOff + 5], + &CDU[dataOff + 6], &CDU[dataOff + 7]); + } + // DCT columns + for (dataOff = 0; dataOff < 8; ++dataOff) { + stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff + 8], &CDU[dataOff + 16], + &CDU[dataOff + 24], &CDU[dataOff + 32], &CDU[dataOff + 40], + &CDU[dataOff + 48], &CDU[dataOff + 56]); + } + // Quantize/descale/zigzag the coefficients + for (i = 0; i < 64; ++i) { + float v = CDU[i] * fdtbl[i]; + // 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) { + int startpos = i; + int nrzeroes; + unsigned short bits[2]; + for (; DU[i] == 0 && i <= end0pos; ++i) { + } + nrzeroes = i - startpos; + if (nrzeroes >= 16) { + int lng = nrzeroes >> 4; + int 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) { + // Constants that don't pollute global namespace + 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 : 90; + 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 = (YQT[i] * quality + 50) / 100; + YTable[stbiw__jpg_ZigZag[i]] = + (unsigned char)(yti < 1 ? 1 : yti > 255 ? 255 : yti); + uvti = (UVQT[i] * quality + 50) / 100; + 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) { + for (col = x; col < x + 8; ++col, ++pos) { + int p = (stbi__flip_vertically_on_write ? height - 1 - row : row) * + width * comp + + col * comp; + float r, g, b; + if (row >= height) { + p -= width * comp * (row + 1 - height); + } + if (col >= width) { + p -= comp * (col + 1 - width); + } + + 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; +} + +STBIWDEF 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); +} + +#ifndef STBI_WRITE_NO_STDIO +STBIWDEF 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; +} +#endif + +#endif // STB_IMAGE_WRITE_IMPLEMENTATION + +/* Revision history + 1.09 (2018-02-11) + fix typo in zlib quality API, improve STB_I_W_STATIC in C++ + 1.08 (2018-01-29) + add stbi__flip_vertically_on_write, external zlib, zlib quality, + choose PNG filter 1.07 (2017-07-24) doc fix 1.06 (2017-07-23) writing JPEG + (using Jon Olick's code) 1.05 ??? 1.04 (2017-03-03) monochrome BMP + expansion 1.03 ??? 1.02 (2016-04-02) avoid allocating large structures on + the stack 1.01 (2016-01-16) STBIW_REALLOC_SIZED: support allocators with no + realloc support avoid race-condition in crc initialization minor compile + issues 1.00 (2015-09-14) installable file IO function 0.99 (2015-09-13) + warning fixes; TGA rle support + 0.98 (2015-04-08) + added STBIW_MALLOC, STBIW_ASSERT etc + 0.97 (2015-01-18) + fixed HDR asserts, rewrote HDR rle logic + 0.96 (2015-01-17) + add HDR output + fix monochrome BMP + 0.95 (2014-08-17) + add monochrome TGA output + 0.94 (2014-05-31) + rename private functions to avoid conflicts with stb_image.h + 0.93 (2014-05-27) + warning fixes + 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 +*/ + +/* +------------------------------------------------------------------------------ +This software is available under 2 licenses -- choose whichever you prefer. +------------------------------------------------------------------------------ +ALTERNATIVE A - MIT License +Copyright (c) 2017 Sean Barrett +Permission is hereby granted, free of charge, to any person obtaining a copy of +this software and associated documentation files (the "Software"), to deal in +the Software without restriction, including without limitation the rights to +use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies +of the Software, and to permit persons to whom the Software is furnished to do +so, subject to the following conditions: +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. +------------------------------------------------------------------------------ +ALTERNATIVE B - Public Domain (www.unlicense.org) +This is free and unencumbered software released into the public domain. +Anyone is free to copy, modify, publish, use, compile, sell, or distribute this +software, either in source code form or as a compiled binary, for any purpose, +commercial or non-commercial, and by any means. +In jurisdictions that recognize copyright laws, the author or authors of this +software dedicate any and all copyright interest in the software to the public +domain. We make this dedication for the benefit of the public at large and to +the detriment of our heirs and successors. We intend this dedication to be an +overt act of relinquishment in perpetuity of all present and future rights to +this software under copyright law. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +------------------------------------------------------------------------------ +*/ \ No newline at end of file