├── CMakeLists.txt ├── LICENSE ├── README.md ├── browse.h ├── main.c ├── stb_image.h └── stb_image_write.h /CMakeLists.txt: -------------------------------------------------------------------------------- 1 | cmake_minimum_required(VERSION 2.8) 2 | project(demo) 3 | 4 | add_executable(demo main.c ) 5 | target_link_libraries(demo -lm) -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Copyright (c) 2018 Zhihan Gao 2 | 3 | MIT License 4 | 5 | Permission is hereby granted, free of charge, to any person obtaining a copy 6 | of this software and associated documentation files (the "Software"), to deal 7 | in the Software without restriction, including without limitation the rights 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 | copies of the Software, and to permit persons to whom the Software is 10 | furnished to do so, subject to the following conditions: 11 | 12 | The above copyright notice and this permission notice shall be included in all 13 | copies or substantial portions of the Software. 14 | 15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # OcrPreprocessing 2 | OCR pre-processing algorithm implementation in C for remove color seal 3 | 4 | # Donating 5 | 6 | If you found this project useful, consider buying me a coffee 7 | 8 | Buy Me A Coffee 9 | -------------------------------------------------------------------------------- /browse.h: -------------------------------------------------------------------------------- 1 | #ifndef DEMO_BROWSE_H 2 | #define DEMO_BROWSE_H 3 | #include 4 | #include 5 | #include 6 | #include 7 | 8 | #if _WIN32 9 | 10 | #include 11 | 12 | #pragma comment(lib,"shell32.lib") 13 | 14 | static void browse(const char *url) 15 | { 16 | ShellExecuteA(NULL,"open", url, NULL, NULL, SW_SHOWNORMAL); 17 | } 18 | 19 | #endif 20 | 21 | #if linux || __FreeBSD__ || __sun&&__SVR4 22 | 23 | #include 24 | #include 25 | #include 26 | 27 | static void browse(const char *url) 28 | { 29 | pid_t childpid; 30 | const char *args[3]; 31 | 32 | const char *browser = getenv("BROWSER"); 33 | if (browser) 34 | browser = strdup(browser); 35 | else 36 | browser = "x-www-browser"; 37 | 38 | args[0] = browser; 39 | args[1] = url; 40 | args[2] = NULL; 41 | 42 | childpid = fork(); 43 | if (childpid == 0) 44 | { 45 | execvp(args[0], (char**)args); 46 | perror(args[0]); // failed to execute 47 | return; 48 | } 49 | } 50 | 51 | #endif 52 | 53 | #if __APPLE__ 54 | 55 | #include 56 | #include 57 | #include 58 | 59 | static void browse(const char *url) 60 | { 61 | pid_t childpid; 62 | const char *args[5]; 63 | 64 | char *browser = getenv("BROWSER"); 65 | if (browser) 66 | { browser = strdup(browser); 67 | args[0] = browser; 68 | args[1] = url; 69 | args[2] = NULL; 70 | } 71 | else 72 | { 73 | //browser = "/Applications/Safari.app/Contents/MacOS/Safari"; 74 | args[0] = "open"; 75 | args[1] = "-a"; 76 | args[2] = "/Applications/Safari.app"; 77 | args[3] = url; 78 | args[4] = NULL; 79 | } 80 | 81 | childpid = fork(); 82 | if (childpid == 0) 83 | { 84 | execvp(args[0], (char**)args); 85 | perror(args[0]); // failed to execute 86 | return; 87 | } 88 | } 89 | 90 | #endif 91 | #endif //DEMO_BROWSE_H 92 | -------------------------------------------------------------------------------- /main.c: -------------------------------------------------------------------------------- 1 | 2 | #if defined(_MSC_VER) 3 | #define _CRT_SECURE_NO_WARNINGS 4 | #include 5 | #define access _access 6 | #else 7 | 8 | #include 9 | 10 | #endif 11 | 12 | #include "browse.h" 13 | 14 | #define USE_SHELL_OPEN 15 | #define STB_IMAGE_STATIC 16 | //ref: 17 | // https://github.com/nothings/stb/blob/master/stb_image.h 18 | // https://github.com/nothings/stb/blob/master/stb_image_write.h 19 | #define STB_IMAGE_IMPLEMENTATION 20 | 21 | #include "stb_image.h" 22 | 23 | #define STB_IMAGE_WRITE_IMPLEMENTATION 24 | 25 | #include "stb_image_write.h" 26 | #include 27 | #include 28 | #include 29 | #include 30 | 31 | 32 | #ifndef max 33 | #define max(a, b) (((a) > (b)) ? (a) : (b)) 34 | #endif 35 | 36 | uint8_t *loadImage(const char *filename, int32_t *Width, int32_t *Height, int32_t *Channels) { 37 | 38 | return stbi_load(filename, Width, Height, Channels, 0); 39 | } 40 | 41 | void saveImage(const char *filename, int32_t Width, int32_t Height, int32_t Channels, uint8_t *Output) { 42 | if (!stbi_write_jpg(filename, Width, Height, Channels, Output, 100)) { 43 | fprintf(stderr, "save file fail.\n"); 44 | return; 45 | } 46 | 47 | #ifdef USE_SHELL_OPEN 48 | browse(filename); 49 | #endif 50 | } 51 | 52 | void splitpath(const char *path, char *drv, char *dir, char *name, char *ext) { 53 | const char *end; 54 | const char *p; 55 | const char *s; 56 | if (path[0] && path[1] == ':') { 57 | if (drv) { 58 | *drv++ = *path++; 59 | *drv++ = *path++; 60 | *drv = '\0'; 61 | } 62 | } else if (drv) 63 | *drv = '\0'; 64 | for (end = path; *end && *end != ':';) 65 | end++; 66 | for (p = end; p > path && *--p != '\\' && *p != '/';) 67 | if (*p == '.') { 68 | end = p; 69 | break; 70 | } 71 | if (ext) 72 | for (s = end; (*ext = *s++);) 73 | ext++; 74 | for (p = end; p > path;) 75 | if (*--p == '\\' || *p == '/') { 76 | p++; 77 | break; 78 | } 79 | if (name) { 80 | for (s = p; s < end;) 81 | *name++ = *s++; 82 | *name = '\0'; 83 | } 84 | if (dir) { 85 | for (s = path; s < p;) 86 | *dir++ = *s++; 87 | *dir = '\0'; 88 | } 89 | } 90 | 91 | void rgb2ycbcr(uint8_t R, uint8_t G, uint8_t B, uint8_t *y, uint8_t *cb, uint8_t *cr) { 92 | *y = (int8_t) ((19595 * R + 38470 * G + 7471 * B) >> 16); 93 | *cb = (int8_t) (((36962 * (B - *y)) >> 16) + 128); 94 | *cr = (int8_t) (((46727 * (R - *y)) >> 16) + 128); 95 | } 96 | 97 | uint8_t clampToByte(int32_t Value) { 98 | return ((Value | ((255 - Value) >> 31)) & ~(Value >> 31)); 99 | } 100 | 101 | int32_t clampI(int32_t Value, int32_t Min, int32_t Max) { 102 | if (Value < Min) 103 | return Min; 104 | else if (Value > Max) 105 | return Max; 106 | else 107 | return Value; 108 | } 109 | 110 | float getHueValue(uint8_t red, uint8_t green, uint8_t blue) { 111 | int32_t max_val, min_val, delta; 112 | if (blue > green) { 113 | max_val = blue; 114 | min_val = green; 115 | } else { 116 | max_val = green; 117 | min_val = blue; 118 | } 119 | if (red > max_val) 120 | max_val = red; 121 | else if (red < min_val) 122 | min_val = red; 123 | if (max_val == min_val) { 124 | return 0.0f; 125 | } else { 126 | delta = max_val - min_val; 127 | if (max_val == red) { 128 | if (green < blue) 129 | return 6.0f + (float) (green - blue) / delta; // (5, 6) 130 | else 131 | return (float) (green - blue) / delta; // (0, 1) 132 | } else if (max_val == green) 133 | return 2.0f + (float) (blue - red) / delta; // (1, 3) 134 | else 135 | return 4.0f + (float) (red - green) / delta; // (3, 5) 136 | } 137 | } 138 | 139 | int32_t CPUImageLocalColorFilter(uint8_t *input, 140 | uint8_t *output, 141 | int32_t width, 142 | int32_t height, 143 | int32_t channels, 144 | uint8_t sampleR, 145 | uint8_t sampleG, 146 | uint8_t sampleB, 147 | int32_t tolerance) { 148 | if ((input == NULL) || (output == NULL)) return -1; 149 | if ((width <= 0) || (height <= 0)) return -1; 150 | if (channels < 3) return -1; 151 | sampleR = clampToByte(sampleR); 152 | sampleG = clampToByte(sampleG); 153 | sampleB = clampToByte(sampleB); 154 | tolerance = clampI(tolerance, 0, 100); 155 | float sampleHue = getHueValue(sampleR, sampleG, sampleB); 156 | float toleranceF = tolerance * 0.01f * 3; 157 | float invTolerance = 1.0f / toleranceF; 158 | for (int32_t Y = 0; Y < height; Y++) { 159 | uint8_t *scanLineIn = input + Y * width * channels; 160 | uint8_t *scanLineOut = output + Y * width * channels; 161 | for (int32_t X = 0; X < width; X++) { 162 | uint8_t blue = scanLineIn[2], green = scanLineIn[1], red = scanLineIn[0]; 163 | uint8_t lum = (uint8_t) ((red * 19595 + green * 38469 + blue * 7472) >> 16); 164 | if (tolerance != 0) { 165 | float curHue = getHueValue(red, green, blue); 166 | float diffHue = sampleHue - curHue; 167 | float opacity, invOpacity, baseLum; 168 | 169 | if (diffHue < 0.0f) diffHue = -diffHue; 170 | if (diffHue > 3.0f) diffHue = 6.0f - diffHue; 171 | 172 | if (diffHue >= toleranceF) 173 | opacity = 1.0f; 174 | else 175 | opacity = diffHue * invTolerance * diffHue * invTolerance; 176 | 177 | baseLum = lum * opacity; 178 | invOpacity = 1.0f - opacity; 179 | 180 | scanLineOut[2] = clampToByte(blue * invOpacity + baseLum); 181 | scanLineOut[1] = clampToByte(green * invOpacity + baseLum); 182 | scanLineOut[0] = clampToByte(red * invOpacity + baseLum); 183 | } else { 184 | if ((blue != sampleB) || (green != sampleG) || (red != sampleR)) { 185 | scanLineOut[2] = blue; 186 | scanLineOut[1] = green; 187 | scanLineOut[0] = red; 188 | } else { 189 | scanLineOut[2] = lum; 190 | scanLineOut[1] = lum; 191 | scanLineOut[0] = lum; 192 | } 193 | } 194 | scanLineIn += channels; 195 | scanLineOut += channels; 196 | } 197 | } 198 | return 0; 199 | } 200 | 201 | 202 | uint8_t CPUImageCalcOstuThreshold(const uint32_t *histgram) { 203 | int32_t minValue = 0; 204 | for (int32_t i = 0; i < 256; i++) { 205 | if (histgram[i] != 0) { 206 | minValue = i; 207 | break; 208 | } 209 | } 210 | int32_t maxValue = 0; 211 | for (int32_t i = 255; i >= 0; i--) { 212 | if (histgram[i] != 0) { 213 | maxValue = i; 214 | break; 215 | } 216 | } 217 | if (maxValue == minValue) 218 | return maxValue; 219 | int32_t pixelIntegral = 0; 220 | int32_t pixelAmount = 0; 221 | for (int32_t Y = minValue; Y <= maxValue; Y++) { 222 | pixelIntegral += histgram[Y] * Y; 223 | pixelAmount += histgram[Y]; 224 | } 225 | float omegaBack, omegaFore, microBack, microFore, sigma; 226 | float sigmaB = -1; 227 | int32_t threshold = 0; 228 | int32_t pixelBack = 0; 229 | int32_t pixelFore = 0; 230 | int32_t pixelIntegralBack = 0; 231 | int32_t pixelIntegralFore = 0; 232 | for (int32_t i = minValue; i <= maxValue; i++) { 233 | pixelBack = pixelBack + histgram[i]; 234 | pixelFore = pixelAmount - pixelBack; 235 | omegaBack = (float) pixelBack / pixelAmount; 236 | omegaFore = (float) pixelFore / pixelAmount; 237 | pixelIntegralBack += histgram[i] * i; 238 | pixelIntegralFore = pixelIntegral - pixelIntegralBack; 239 | microBack = (float) pixelIntegralBack / pixelBack; 240 | microFore = (float) pixelIntegralFore / pixelFore; 241 | sigma = omegaBack * omegaFore * (microBack - microFore) * (microBack - microFore); 242 | if (sigma > sigmaB) { 243 | sigmaB = sigma; 244 | threshold = i; 245 | } 246 | } 247 | return threshold; 248 | } 249 | 250 | void CPUImageExtractOstu(const uint8_t *input, uint8_t *gray, uint32_t *histogram, int32_t width, int32_t height, 251 | int32_t stride, int32_t extractChannels) { 252 | int32_t channels = stride / width; 253 | if (channels == 1) { 254 | return; 255 | } 256 | memset(histogram, 0, sizeof(uint32_t) * 256); 257 | for (int32_t y = 0; y < height; y++) { 258 | uint8_t *output = gray + (y * width); 259 | const uint8_t *in = input + (y * stride); 260 | for (int32_t x = 0; x < width; x++) { 261 | output[x] = in[extractChannels]; 262 | histogram[in[extractChannels]]++; 263 | in += channels; 264 | } 265 | } 266 | } 267 | 268 | void CPUImageOstuFilter(uint8_t *Input, uint32_t *Histogram, int32_t Width, int32_t Height) { 269 | int32_t ostuThreshold = CPUImageCalcOstuThreshold(Histogram); 270 | uint8_t thrMap[256] = {0}; 271 | for (int32_t i = 0; i < 256; i++) { 272 | if (i > ostuThreshold) 273 | thrMap[i] = 255; 274 | else 275 | thrMap[i] = 0; 276 | } 277 | for (int32_t Y = 0; Y < Height; Y++) { 278 | uint8_t *pOutput = Input + (Y * Width); 279 | for (int32_t X = 0; X < Width; X++) { 280 | pOutput[X] = thrMap[pOutput[X]]; 281 | } 282 | } 283 | } 284 | 285 | 286 | int16_t extractWhichChannels(const uint8_t *input, 287 | int32_t width, 288 | int32_t height, 289 | int32_t channels) { 290 | uint32_t histogram[256 * 2] = {0}; 291 | memset(histogram, 0, 256 * 2 * sizeof(uint32_t)); 292 | uint32_t *histogramCr = &histogram[0]; 293 | uint32_t *histogramCb = &histogram[256]; 294 | for (int32_t y = 0; y < height; y++) { 295 | const uint8_t *scanLineIn = input + y * width * channels; 296 | uint8_t Y = 0; 297 | uint8_t Cb = 0; 298 | uint8_t Cr = 0; 299 | for (int32_t x = 0; x < width; x++) { 300 | rgb2ycbcr(scanLineIn[0], scanLineIn[1], scanLineIn[2], &Y, &Cb, &Cr); 301 | histogramCb[Cb]++; 302 | histogramCr[Cr]++; 303 | scanLineIn += channels; 304 | } 305 | } 306 | uint64_t sumCb = 0; 307 | uint64_t sumCr = 0; 308 | 309 | for (int i = 0; i < 256; i++) { 310 | sumCb += histogramCb[i] * i; 311 | sumCr += histogramCr[i] * i; 312 | } 313 | if (sumCb == sumCr) 314 | return 1; 315 | uint64_t meanMax = max(sumCb, sumCr); 316 | if (meanMax == sumCr) 317 | return 0; 318 | return 2; 319 | } 320 | 321 | void colorFilterExtract(const uint8_t *input, uint8_t *output, int32_t width, int32_t height, int32_t channels, 322 | uint32_t *histogram, int32_t extractChannels) { 323 | CPUImageExtractOstu(input, output, histogram, width, height, width * channels, extractChannels); 324 | CPUImageOstuFilter(output, histogram, width, height); 325 | } 326 | 327 | int main(int argc, char **argv) { 328 | printf("Image Processing \n "); 329 | printf("blog:http://cpuimage.cnblogs.com/ \n "); 330 | printf("Color Eraser\n "); 331 | if (argc < 2) { 332 | printf("usage: \n "); 333 | printf("%s filename \n ", argv[0]); 334 | printf("%s image.jpg \n ", argv[0]); 335 | getchar(); 336 | return 0; 337 | } 338 | char *in_file = argv[1]; 339 | if (access(in_file, 0) == -1) { 340 | printf("load file: %s fail!\n", in_file); 341 | return -1; 342 | } 343 | char drive[3]; 344 | char dir[256]; 345 | char fname[256]; 346 | char ext[256]; 347 | char out_file[1024]; 348 | splitpath(in_file, drive, dir, fname, ext); 349 | sprintf(out_file, "%s%s%s_out.jpg", drive, dir, fname); 350 | 351 | int32_t width = 0; 352 | int32_t height = 0; 353 | int32_t channels = 0; 354 | uint8_t *input = NULL; 355 | input = loadImage(in_file, &width, &height, &channels); 356 | 357 | if (input) { 358 | uint8_t *output = (uint8_t *) malloc(width * channels * height * sizeof(uint8_t)); 359 | if (output) { 360 | // LocalColor Version 361 | if (true) { 362 | uint8_t sampleR = 255; 363 | uint8_t sampleG = 0; 364 | uint8_t sampleB = 0; 365 | int32_t tolerance = 50; 366 | CPUImageLocalColorFilter(input, output, width, height, channels, sampleR, sampleG, sampleB, tolerance); 367 | // saveImage(out_file, width, height, channels, output); 368 | uint32_t histogram[256] = {0}; 369 | int32_t extractChannels = extractWhichChannels(output, width, height, channels); // [0,2] rgb or bgr 370 | colorFilterExtract(output, output, width, height, channels, histogram, extractChannels); 371 | saveImage(out_file, width, height, 1, output); 372 | } else { 373 | // Simple Version 374 | int extractChannels = 0; 375 | uint32_t histogram[256] = {0}; 376 | colorFilterExtract(input, output, width, height, channels, histogram, extractChannels); 377 | saveImage(out_file, width, height, 1, output); 378 | } 379 | free(output); 380 | } 381 | free(input); 382 | } else { 383 | printf("load file: %s fail!\n", in_file); 384 | } 385 | printf("press any key to exit. \n"); 386 | getchar(); 387 | return 0; 388 | } -------------------------------------------------------------------------------- /stb_image_write.h: -------------------------------------------------------------------------------- 1 | /* stb_image_write - v1.09 - public domain - http://nothings.org/stb/stb_image_write.h 2 | writes out PNG/BMP/TGA/JPEG/HDR images to C stdio - Sean Barrett 2010-2015 3 | no warranty implied; use at your own risk 4 | 5 | Before #including, 6 | 7 | #define STB_IMAGE_WRITE_IMPLEMENTATION 8 | 9 | in the file that you want to have the implementation. 10 | 11 | Will probably not work correctly with strict-aliasing optimizations. 12 | 13 | If using a modern Microsoft Compiler, non-safe versions of CRT calls may cause 14 | compilation warnings or even errors. To avoid this, also before #including, 15 | 16 | #define STBI_MSC_SECURE_CRT 17 | 18 | ABOUT: 19 | 20 | This header file is a library for writing images to C stdio. It could be 21 | adapted to write to memory or a general streaming interface; let me know. 22 | 23 | The PNG output is not optimal; it is 20-50% larger than the file 24 | written by a decent optimizing implementation; though providing a custom 25 | zlib compress function (see STBIW_ZLIB_COMPRESS) can mitigate that. 26 | This library is designed for source code compactness and simplicity, 27 | not optimal image file size or run-time performance. 28 | 29 | BUILDING: 30 | 31 | You can #define STBIW_ASSERT(x) before the #include to avoid using assert.h. 32 | You can #define STBIW_MALLOC(), STBIW_REALLOC(), and STBIW_FREE() to replace 33 | malloc,realloc,free. 34 | You can #define STBIW_MEMMOVE() to replace memmove() 35 | You can #define STBIW_ZLIB_COMPRESS to use a custom zlib-style compress function 36 | for PNG compression (instead of the builtin one), it must have the following signature: 37 | unsigned char * my_compress(unsigned char *data, int data_len, int *out_len, int quality); 38 | The returned data will be freed with STBIW_FREE() (free() by default), 39 | so it must be heap allocated with STBIW_MALLOC() (malloc() by default), 40 | 41 | USAGE: 42 | 43 | There are five functions, one for each image file format: 44 | 45 | int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes); 46 | int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data); 47 | int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data); 48 | int stbi_write_jpg(char const *filename, int w, int h, int comp, const void *data, int quality); 49 | int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data); 50 | 51 | void stbi_flip_vertically_on_write(int flag); // flag is non-zero to flip data vertically 52 | 53 | There are also five equivalent functions that use an arbitrary write function. You are 54 | expected to open/close your file-equivalent before and after calling these: 55 | 56 | 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); 57 | int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 58 | int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 59 | int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data); 60 | int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality); 61 | 62 | where the callback is: 63 | void stbi_write_func(void *context, void *data, int size); 64 | 65 | You can configure it with these global variables: 66 | int stbi_write_tga_with_rle; // defaults to true; set to 0 to disable RLE 67 | int stbi_write_png_compression_level; // defaults to 8; set to higher for more compression 68 | int stbi_write_force_png_filter; // defaults to -1; set to 0..5 to force a filter mode 69 | 70 | 71 | You can define STBI_WRITE_NO_STDIO to disable the file variant of these 72 | functions, so the library will not use stdio.h at all. However, this will 73 | also disable HDR writing, because it requires stdio for formatted output. 74 | 75 | Each function returns 0 on failure and non-0 on success. 76 | 77 | The functions create an image file defined by the parameters. The image 78 | is a rectangle of pixels stored from left-to-right, top-to-bottom. 79 | Each pixel contains 'comp' channels of data stored interleaved with 8-bits 80 | per channel, in the following order: 1=Y, 2=YA, 3=RGB, 4=RGBA. (Y is 81 | monochrome color.) The rectangle is 'w' pixels wide and 'h' pixels tall. 82 | The *data pointer points to the first byte of the top-left-most pixel. 83 | For PNG, "stride_in_bytes" is the distance in bytes from the first byte of 84 | a row of pixels to the first byte of the next row of pixels. 85 | 86 | PNG creates output files with the same number of components as the input. 87 | The BMP format expands Y to RGB in the file format and does not 88 | output alpha. 89 | 90 | PNG supports writing rectangles of data even when the bytes storing rows of 91 | data are not consecutive in memory (e.g. sub-rectangles of a larger image), 92 | by supplying the stride between the beginning of adjacent rows. The other 93 | formats do not. (Thus you cannot write a native-format BMP through the BMP 94 | writer, both because it is in BGR order and because it may have padding 95 | at the end of the line.) 96 | 97 | PNG allows you to set the deflate compression level by setting the global 98 | variable 'stbi_write_png_compression_level' (it defaults to 8). 99 | 100 | HDR expects linear float data. Since the format is always 32-bit rgb(e) 101 | data, alpha (if provided) is discarded, and for monochrome data it is 102 | replicated across all three channels. 103 | 104 | TGA supports RLE or non-RLE compressed data. To use non-RLE-compressed 105 | data, set the global variable 'stbi_write_tga_with_rle' to 0. 106 | 107 | JPEG does ignore alpha channels in input data; quality is between 1 and 100. 108 | Higher quality looks better but results in a bigger image. 109 | JPEG baseline (no JPEG progressive). 110 | 111 | CREDITS: 112 | 113 | 114 | Sean Barrett - PNG/BMP/TGA 115 | Baldur Karlsson - HDR 116 | Jean-Sebastien Guay - TGA monochrome 117 | Tim Kelsey - misc enhancements 118 | Alan Hickman - TGA RLE 119 | Emmanuel Julien - initial file IO callback implementation 120 | Jon Olick - original jo_jpeg.cpp code 121 | Daniel Gibson - integrate JPEG, allow external zlib 122 | Aarni Koskela - allow choosing PNG filter 123 | 124 | bugfixes: 125 | github:Chribba 126 | Guillaume Chereau 127 | github:jry2 128 | github:romigrou 129 | Sergio Gonzalez 130 | Jonas Karlsson 131 | Filip Wasil 132 | Thatcher Ulrich 133 | github:poppolopoppo 134 | Patrick Boettcher 135 | github:xeekworx 136 | Cap Petschulat 137 | Simon Rodriguez 138 | Ivan Tikhonov 139 | github:ignotion 140 | Adam Schackart 141 | 142 | LICENSE 143 | 144 | See end of file for license information. 145 | 146 | */ 147 | 148 | #ifndef INCLUDE_STB_IMAGE_WRITE_H 149 | #define INCLUDE_STB_IMAGE_WRITE_H 150 | 151 | // if STB_IMAGE_WRITE_STATIC causes problems, try defining STBIWDEF to 'inline' or 'static inline' 152 | #ifndef STBIWDEF 153 | #ifdef STB_IMAGE_WRITE_STATIC 154 | #define STBIWDEF static 155 | #else 156 | #ifdef __cplusplus 157 | #define STBIWDEF extern "C" 158 | #else 159 | #define STBIWDEF extern 160 | #endif 161 | #endif 162 | #endif 163 | 164 | #ifndef STB_IMAGE_WRITE_STATIC // C++ forbids static forward declarations 165 | extern int stbi_write_tga_with_rle; 166 | extern int stbi_write_png_compression_level; 167 | extern int stbi_write_force_png_filter; 168 | #endif 169 | 170 | #ifndef STBI_WRITE_NO_STDIO 171 | STBIWDEF int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes); 172 | STBIWDEF int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data); 173 | STBIWDEF int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data); 174 | STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data); 175 | STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality); 176 | #endif 177 | 178 | typedef void stbi_write_func(void *context, void *data, int size); 179 | 180 | 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); 181 | STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 182 | STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void *data); 183 | STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data); 184 | STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality); 185 | 186 | STBIWDEF void stbi_flip_vertically_on_write(int flip_boolean); 187 | 188 | #endif//INCLUDE_STB_IMAGE_WRITE_H 189 | 190 | #ifdef STB_IMAGE_WRITE_IMPLEMENTATION 191 | 192 | #ifdef _WIN32 193 | #ifndef _CRT_SECURE_NO_WARNINGS 194 | #define _CRT_SECURE_NO_WARNINGS 195 | #endif 196 | #ifndef _CRT_NONSTDC_NO_DEPRECATE 197 | #define _CRT_NONSTDC_NO_DEPRECATE 198 | #endif 199 | #endif 200 | 201 | #ifndef STBI_WRITE_NO_STDIO 202 | #include 203 | #endif // STBI_WRITE_NO_STDIO 204 | 205 | #include 206 | #include 207 | #include 208 | #include 209 | 210 | #if defined(STBIW_MALLOC) && defined(STBIW_FREE) && (defined(STBIW_REALLOC) || defined(STBIW_REALLOC_SIZED)) 211 | // ok 212 | #elif !defined(STBIW_MALLOC) && !defined(STBIW_FREE) && !defined(STBIW_REALLOC) && !defined(STBIW_REALLOC_SIZED) 213 | // ok 214 | #else 215 | #error "Must define all or none of STBIW_MALLOC, STBIW_FREE, and STBIW_REALLOC (or STBIW_REALLOC_SIZED)." 216 | #endif 217 | 218 | #ifndef STBIW_MALLOC 219 | #define STBIW_MALLOC(sz) malloc(sz) 220 | #define STBIW_REALLOC(p,newsz) realloc(p,newsz) 221 | #define STBIW_FREE(p) free(p) 222 | #endif 223 | 224 | #ifndef STBIW_REALLOC_SIZED 225 | #define STBIW_REALLOC_SIZED(p,oldsz,newsz) STBIW_REALLOC(p,newsz) 226 | #endif 227 | 228 | 229 | #ifndef STBIW_MEMMOVE 230 | #define STBIW_MEMMOVE(a,b,sz) memmove(a,b,sz) 231 | #endif 232 | 233 | 234 | #ifndef STBIW_ASSERT 235 | #include 236 | #define STBIW_ASSERT(x) assert(x) 237 | #endif 238 | 239 | #define STBIW_UCHAR(x) (unsigned char) ((x) & 0xff) 240 | 241 | #ifdef STB_IMAGE_WRITE_STATIC 242 | static int stbi__flip_vertically_on_write=0; 243 | static int stbi_write_png_compression_level = 8; 244 | static int stbi_write_tga_with_rle = 1; 245 | static int stbi_write_force_png_filter = -1; 246 | #else 247 | int stbi_write_png_compression_level = 8; 248 | int stbi__flip_vertically_on_write=0; 249 | int stbi_write_tga_with_rle = 1; 250 | int stbi_write_force_png_filter = -1; 251 | #endif 252 | 253 | STBIWDEF void stbi_flip_vertically_on_write(int flag) 254 | { 255 | stbi__flip_vertically_on_write = flag; 256 | } 257 | 258 | typedef struct 259 | { 260 | stbi_write_func *func; 261 | void *context; 262 | } stbi__write_context; 263 | 264 | // initialize a callback-based context 265 | static void stbi__start_write_callbacks(stbi__write_context *s, stbi_write_func *c, void *context) 266 | { 267 | s->func = c; 268 | s->context = context; 269 | } 270 | 271 | #ifndef STBI_WRITE_NO_STDIO 272 | 273 | static void stbi__stdio_write(void *context, void *data, int size) 274 | { 275 | fwrite(data,1,size,(FILE*) context); 276 | } 277 | 278 | static int stbi__start_write_file(stbi__write_context *s, const char *filename) 279 | { 280 | FILE *f; 281 | #ifdef STBI_MSC_SECURE_CRT 282 | if (fopen_s(&f, filename, "wb")) 283 | f = NULL; 284 | #else 285 | f = fopen(filename, "wb"); 286 | #endif 287 | stbi__start_write_callbacks(s, stbi__stdio_write, (void *) f); 288 | return f != NULL; 289 | } 290 | 291 | static void stbi__end_write_file(stbi__write_context *s) 292 | { 293 | fclose((FILE *)s->context); 294 | } 295 | 296 | #endif // !STBI_WRITE_NO_STDIO 297 | 298 | typedef unsigned int stbiw_uint32; 299 | typedef int stb_image_write_test[sizeof(stbiw_uint32)==4 ? 1 : -1]; 300 | 301 | static void stbiw__writefv(stbi__write_context *s, const char *fmt, va_list v) 302 | { 303 | while (*fmt) { 304 | switch (*fmt++) { 305 | case ' ': break; 306 | case '1': { unsigned char x = STBIW_UCHAR(va_arg(v, int)); 307 | s->func(s->context,&x,1); 308 | break; } 309 | case '2': { int x = va_arg(v,int); 310 | unsigned char b[2]; 311 | b[0] = STBIW_UCHAR(x); 312 | b[1] = STBIW_UCHAR(x>>8); 313 | s->func(s->context,b,2); 314 | break; } 315 | case '4': { stbiw_uint32 x = va_arg(v,int); 316 | unsigned char b[4]; 317 | b[0]=STBIW_UCHAR(x); 318 | b[1]=STBIW_UCHAR(x>>8); 319 | b[2]=STBIW_UCHAR(x>>16); 320 | b[3]=STBIW_UCHAR(x>>24); 321 | s->func(s->context,b,4); 322 | break; } 323 | default: 324 | STBIW_ASSERT(0); 325 | return; 326 | } 327 | } 328 | } 329 | 330 | static void stbiw__writef(stbi__write_context *s, const char *fmt, ...) 331 | { 332 | va_list v; 333 | va_start(v, fmt); 334 | stbiw__writefv(s, fmt, v); 335 | va_end(v); 336 | } 337 | 338 | static void stbiw__putc(stbi__write_context *s, unsigned char c) 339 | { 340 | s->func(s->context, &c, 1); 341 | } 342 | 343 | static void stbiw__write3(stbi__write_context *s, unsigned char a, unsigned char b, unsigned char c) 344 | { 345 | unsigned char arr[3]; 346 | arr[0] = a, arr[1] = b, arr[2] = c; 347 | s->func(s->context, arr, 3); 348 | } 349 | 350 | static void stbiw__write_pixel(stbi__write_context *s, int rgb_dir, int comp, int write_alpha, int expand_mono, unsigned char *d) 351 | { 352 | unsigned char bg[3] = { 255, 0, 255}, px[3]; 353 | int k; 354 | 355 | if (write_alpha < 0) 356 | s->func(s->context, &d[comp - 1], 1); 357 | 358 | switch (comp) { 359 | case 2: // 2 pixels = mono + alpha, alpha is written separately, so same as 1-channel case 360 | case 1: 361 | if (expand_mono) 362 | stbiw__write3(s, d[0], d[0], d[0]); // monochrome bmp 363 | else 364 | s->func(s->context, d, 1); // monochrome TGA 365 | break; 366 | case 4: 367 | if (!write_alpha) { 368 | // composite against pink background 369 | for (k = 0; k < 3; ++k) 370 | px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255; 371 | stbiw__write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]); 372 | break; 373 | } 374 | /* FALLTHROUGH */ 375 | case 3: 376 | stbiw__write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]); 377 | break; 378 | } 379 | if (write_alpha > 0) 380 | s->func(s->context, &d[comp - 1], 1); 381 | } 382 | 383 | 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) 384 | { 385 | stbiw_uint32 zero = 0; 386 | int i,j, j_end; 387 | 388 | if (y <= 0) 389 | return; 390 | 391 | if (stbi__flip_vertically_on_write) 392 | vdir *= -1; 393 | 394 | if (vdir < 0) 395 | j_end = -1, j = y-1; 396 | else 397 | j_end = y, j = 0; 398 | 399 | for (; j != j_end; j += vdir) { 400 | for (i=0; i < x; ++i) { 401 | unsigned char *d = (unsigned char *) data + (j*x+i)*comp; 402 | stbiw__write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d); 403 | } 404 | s->func(s->context, &zero, scanline_pad); 405 | } 406 | } 407 | 408 | 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, ...) 409 | { 410 | if (y < 0 || x < 0) { 411 | return 0; 412 | } else { 413 | va_list v; 414 | va_start(v, fmt); 415 | stbiw__writefv(s, fmt, v); 416 | va_end(v); 417 | stbiw__write_pixels(s,rgb_dir,vdir,x,y,comp,data,alpha,pad, expand_mono); 418 | return 1; 419 | } 420 | } 421 | 422 | static int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp, const void *data) 423 | { 424 | int pad = (-x*3) & 3; 425 | return stbiw__outfile(s,-1,-1,x,y,comp,1,(void *) data,0,pad, 426 | "11 4 22 4" "4 44 22 444444", 427 | 'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40, // file header 428 | 40, x,y, 1,24, 0,0,0,0,0,0); // bitmap header 429 | } 430 | 431 | STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data) 432 | { 433 | stbi__write_context s; 434 | stbi__start_write_callbacks(&s, func, context); 435 | return stbi_write_bmp_core(&s, x, y, comp, data); 436 | } 437 | 438 | #ifndef STBI_WRITE_NO_STDIO 439 | STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data) 440 | { 441 | stbi__write_context s; 442 | if (stbi__start_write_file(&s,filename)) { 443 | int r = stbi_write_bmp_core(&s, x, y, comp, data); 444 | stbi__end_write_file(&s); 445 | return r; 446 | } else 447 | return 0; 448 | } 449 | #endif //!STBI_WRITE_NO_STDIO 450 | 451 | static int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp, void *data) 452 | { 453 | int has_alpha = (comp == 2 || comp == 4); 454 | int colorbytes = has_alpha ? comp-1 : comp; 455 | int format = colorbytes < 2 ? 3 : 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3 456 | 457 | if (y < 0 || x < 0) 458 | return 0; 459 | 460 | if (!stbi_write_tga_with_rle) { 461 | return stbiw__outfile(s, -1, -1, x, y, comp, 0, (void *) data, has_alpha, 0, 462 | "111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y, (colorbytes + has_alpha) * 8, has_alpha * 8); 463 | } else { 464 | int i,j,k; 465 | int jend, jdir; 466 | 467 | 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); 468 | 469 | if (stbi__flip_vertically_on_write) { 470 | j = 0; 471 | jend = y; 472 | jdir = 1; 473 | } else { 474 | j = y-1; 475 | jend = -1; 476 | jdir = -1; 477 | } 478 | for (; j != jend; j += jdir) { 479 | unsigned char *row = (unsigned char *) data + j * x * comp; 480 | int len; 481 | 482 | for (i = 0; i < x; i += len) { 483 | unsigned char *begin = row + i * comp; 484 | int diff = 1; 485 | len = 1; 486 | 487 | if (i < x - 1) { 488 | ++len; 489 | diff = memcmp(begin, row + (i + 1) * comp, comp); 490 | if (diff) { 491 | const unsigned char *prev = begin; 492 | for (k = i + 2; k < x && len < 128; ++k) { 493 | if (memcmp(prev, row + k * comp, comp)) { 494 | prev += comp; 495 | ++len; 496 | } else { 497 | --len; 498 | break; 499 | } 500 | } 501 | } else { 502 | for (k = i + 2; k < x && len < 128; ++k) { 503 | if (!memcmp(begin, row + k * comp, comp)) { 504 | ++len; 505 | } else { 506 | break; 507 | } 508 | } 509 | } 510 | } 511 | 512 | if (diff) { 513 | unsigned char header = STBIW_UCHAR(len - 1); 514 | s->func(s->context, &header, 1); 515 | for (k = 0; k < len; ++k) { 516 | stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp); 517 | } 518 | } else { 519 | unsigned char header = STBIW_UCHAR(len - 129); 520 | s->func(s->context, &header, 1); 521 | stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin); 522 | } 523 | } 524 | } 525 | } 526 | return 1; 527 | } 528 | 529 | STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data) 530 | { 531 | stbi__write_context s; 532 | stbi__start_write_callbacks(&s, func, context); 533 | return stbi_write_tga_core(&s, x, y, comp, (void *) data); 534 | } 535 | 536 | #ifndef STBI_WRITE_NO_STDIO 537 | STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, const void *data) 538 | { 539 | stbi__write_context s; 540 | if (stbi__start_write_file(&s,filename)) { 541 | int r = stbi_write_tga_core(&s, x, y, comp, (void *) data); 542 | stbi__end_write_file(&s); 543 | return r; 544 | } else 545 | return 0; 546 | } 547 | #endif 548 | 549 | // ************************************************************************************************* 550 | // Radiance RGBE HDR writer 551 | // by Baldur Karlsson 552 | 553 | #define stbiw__max(a, b) ((a) > (b) ? (a) : (b)) 554 | 555 | void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear) 556 | { 557 | int exponent; 558 | float maxcomp = stbiw__max(linear[0], stbiw__max(linear[1], linear[2])); 559 | 560 | if (maxcomp < 1e-32f) { 561 | rgbe[0] = rgbe[1] = rgbe[2] = rgbe[3] = 0; 562 | } else { 563 | float normalize = (float) frexp(maxcomp, &exponent) * 256.0f/maxcomp; 564 | 565 | rgbe[0] = (unsigned char)(linear[0] * normalize); 566 | rgbe[1] = (unsigned char)(linear[1] * normalize); 567 | rgbe[2] = (unsigned char)(linear[2] * normalize); 568 | rgbe[3] = (unsigned char)(exponent + 128); 569 | } 570 | } 571 | 572 | void stbiw__write_run_data(stbi__write_context *s, int length, unsigned char databyte) 573 | { 574 | unsigned char lengthbyte = STBIW_UCHAR(length+128); 575 | STBIW_ASSERT(length+128 <= 255); 576 | s->func(s->context, &lengthbyte, 1); 577 | s->func(s->context, &databyte, 1); 578 | } 579 | 580 | void stbiw__write_dump_data(stbi__write_context *s, int length, unsigned char *data) 581 | { 582 | unsigned char lengthbyte = STBIW_UCHAR(length); 583 | STBIW_ASSERT(length <= 128); // inconsistent with spec but consistent with official code 584 | s->func(s->context, &lengthbyte, 1); 585 | s->func(s->context, data, length); 586 | } 587 | 588 | void stbiw__write_hdr_scanline(stbi__write_context *s, int width, int ncomp, unsigned char *scratch, float *scanline) 589 | { 590 | unsigned char scanlineheader[4] = { 2, 2, 0, 0 }; 591 | unsigned char rgbe[4]; 592 | float linear[3]; 593 | int x; 594 | 595 | scanlineheader[2] = (width&0xff00)>>8; 596 | scanlineheader[3] = (width&0x00ff); 597 | 598 | /* skip RLE for images too small or large */ 599 | if (width < 8 || width >= 32768) { 600 | for (x=0; x < width; x++) { 601 | switch (ncomp) { 602 | case 4: /* fallthrough */ 603 | case 3: linear[2] = scanline[x*ncomp + 2]; 604 | linear[1] = scanline[x*ncomp + 1]; 605 | linear[0] = scanline[x*ncomp + 0]; 606 | break; 607 | default: 608 | linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0]; 609 | break; 610 | } 611 | stbiw__linear_to_rgbe(rgbe, linear); 612 | s->func(s->context, rgbe, 4); 613 | } 614 | } else { 615 | int c,r; 616 | /* encode into scratch buffer */ 617 | for (x=0; x < width; x++) { 618 | switch(ncomp) { 619 | case 4: /* fallthrough */ 620 | case 3: linear[2] = scanline[x*ncomp + 2]; 621 | linear[1] = scanline[x*ncomp + 1]; 622 | linear[0] = scanline[x*ncomp + 0]; 623 | break; 624 | default: 625 | linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0]; 626 | break; 627 | } 628 | stbiw__linear_to_rgbe(rgbe, linear); 629 | scratch[x + width*0] = rgbe[0]; 630 | scratch[x + width*1] = rgbe[1]; 631 | scratch[x + width*2] = rgbe[2]; 632 | scratch[x + width*3] = rgbe[3]; 633 | } 634 | 635 | s->func(s->context, scanlineheader, 4); 636 | 637 | /* RLE each component separately */ 638 | for (c=0; c < 4; c++) { 639 | unsigned char *comp = &scratch[width*c]; 640 | 641 | x = 0; 642 | while (x < width) { 643 | // find first run 644 | r = x; 645 | while (r+2 < width) { 646 | if (comp[r] == comp[r+1] && comp[r] == comp[r+2]) 647 | break; 648 | ++r; 649 | } 650 | if (r+2 >= width) 651 | r = width; 652 | // dump up to first run 653 | while (x < r) { 654 | int len = r-x; 655 | if (len > 128) len = 128; 656 | stbiw__write_dump_data(s, len, &comp[x]); 657 | x += len; 658 | } 659 | // if there's a run, output it 660 | if (r+2 < width) { // same test as what we break out of in search loop, so only true if we break'd 661 | // find next byte after run 662 | while (r < width && comp[r] == comp[x]) 663 | ++r; 664 | // output run up to r 665 | while (x < r) { 666 | int len = r-x; 667 | if (len > 127) len = 127; 668 | stbiw__write_run_data(s, len, comp[x]); 669 | x += len; 670 | } 671 | } 672 | } 673 | } 674 | } 675 | } 676 | 677 | static int stbi_write_hdr_core(stbi__write_context *s, int x, int y, int comp, float *data) 678 | { 679 | if (y <= 0 || x <= 0 || data == NULL) 680 | return 0; 681 | else { 682 | // Each component is stored separately. Allocate scratch space for full output scanline. 683 | unsigned char *scratch = (unsigned char *) STBIW_MALLOC(x*4); 684 | int i, len; 685 | char buffer[128]; 686 | char header[] = "#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n"; 687 | s->func(s->context, header, sizeof(header)-1); 688 | 689 | #ifdef STBI_MSC_SECURE_CRT 690 | len = sprintf_s(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x); 691 | #else 692 | len = sprintf(buffer, "EXPOSURE= 1.0000000000000\n\n-Y %d +X %d\n", y, x); 693 | #endif 694 | s->func(s->context, buffer, len); 695 | 696 | for(i=0; i < y; i++) 697 | stbiw__write_hdr_scanline(s, x, comp, scratch, data + comp*x*(stbi__flip_vertically_on_write ? y-1-i : i)*x); 698 | STBIW_FREE(scratch); 699 | return 1; 700 | } 701 | } 702 | 703 | STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const float *data) 704 | { 705 | stbi__write_context s; 706 | stbi__start_write_callbacks(&s, func, context); 707 | return stbi_write_hdr_core(&s, x, y, comp, (float *) data); 708 | } 709 | 710 | #ifndef STBI_WRITE_NO_STDIO 711 | STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const float *data) 712 | { 713 | stbi__write_context s; 714 | if (stbi__start_write_file(&s,filename)) { 715 | int r = stbi_write_hdr_core(&s, x, y, comp, (float *) data); 716 | stbi__end_write_file(&s); 717 | return r; 718 | } else 719 | return 0; 720 | } 721 | #endif // STBI_WRITE_NO_STDIO 722 | 723 | 724 | ////////////////////////////////////////////////////////////////////////////// 725 | // 726 | // PNG writer 727 | // 728 | 729 | #ifndef STBIW_ZLIB_COMPRESS 730 | // stretchy buffer; stbiw__sbpush() == vector<>::push_back() -- stbiw__sbcount() == vector<>::size() 731 | #define stbiw__sbraw(a) ((int *) (a) - 2) 732 | #define stbiw__sbm(a) stbiw__sbraw(a)[0] 733 | #define stbiw__sbn(a) stbiw__sbraw(a)[1] 734 | 735 | #define stbiw__sbneedgrow(a,n) ((a)==0 || stbiw__sbn(a)+n >= stbiw__sbm(a)) 736 | #define stbiw__sbmaybegrow(a,n) (stbiw__sbneedgrow(a,(n)) ? stbiw__sbgrow(a,n) : 0) 737 | #define stbiw__sbgrow(a,n) stbiw__sbgrowf((void **) &(a), (n), sizeof(*(a))) 738 | 739 | #define stbiw__sbpush(a, v) (stbiw__sbmaybegrow(a,1), (a)[stbiw__sbn(a)++] = (v)) 740 | #define stbiw__sbcount(a) ((a) ? stbiw__sbn(a) : 0) 741 | #define stbiw__sbfree(a) ((a) ? STBIW_FREE(stbiw__sbraw(a)),0 : 0) 742 | 743 | static void *stbiw__sbgrowf(void **arr, int increment, int itemsize) 744 | { 745 | int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1; 746 | void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2); 747 | STBIW_ASSERT(p); 748 | if (p) { 749 | if (!*arr) ((int *) p)[1] = 0; 750 | *arr = (void *) ((int *) p + 2); 751 | stbiw__sbm(*arr) = m; 752 | } 753 | return *arr; 754 | } 755 | 756 | static unsigned char *stbiw__zlib_flushf(unsigned char *data, unsigned int *bitbuffer, int *bitcount) 757 | { 758 | while (*bitcount >= 8) { 759 | stbiw__sbpush(data, STBIW_UCHAR(*bitbuffer)); 760 | *bitbuffer >>= 8; 761 | *bitcount -= 8; 762 | } 763 | return data; 764 | } 765 | 766 | static int stbiw__zlib_bitrev(int code, int codebits) 767 | { 768 | int res=0; 769 | while (codebits--) { 770 | res = (res << 1) | (code & 1); 771 | code >>= 1; 772 | } 773 | return res; 774 | } 775 | 776 | static unsigned int stbiw__zlib_countm(unsigned char *a, unsigned char *b, int limit) 777 | { 778 | int i; 779 | for (i=0; i < limit && i < 258; ++i) 780 | if (a[i] != b[i]) break; 781 | return i; 782 | } 783 | 784 | static unsigned int stbiw__zhash(unsigned char *data) 785 | { 786 | stbiw_uint32 hash = data[0] + (data[1] << 8) + (data[2] << 16); 787 | hash ^= hash << 3; 788 | hash += hash >> 5; 789 | hash ^= hash << 4; 790 | hash += hash >> 17; 791 | hash ^= hash << 25; 792 | hash += hash >> 6; 793 | return hash; 794 | } 795 | 796 | #define stbiw__zlib_flush() (out = stbiw__zlib_flushf(out, &bitbuf, &bitcount)) 797 | #define stbiw__zlib_add(code,codebits) \ 798 | (bitbuf |= (code) << bitcount, bitcount += (codebits), stbiw__zlib_flush()) 799 | #define stbiw__zlib_huffa(b,c) stbiw__zlib_add(stbiw__zlib_bitrev(b,c),c) 800 | // default huffman tables 801 | #define stbiw__zlib_huff1(n) stbiw__zlib_huffa(0x30 + (n), 8) 802 | #define stbiw__zlib_huff2(n) stbiw__zlib_huffa(0x190 + (n)-144, 9) 803 | #define stbiw__zlib_huff3(n) stbiw__zlib_huffa(0 + (n)-256,7) 804 | #define stbiw__zlib_huff4(n) stbiw__zlib_huffa(0xc0 + (n)-280,8) 805 | #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)) 806 | #define stbiw__zlib_huffb(n) ((n) <= 143 ? stbiw__zlib_huff1(n) : stbiw__zlib_huff2(n)) 807 | 808 | #define stbiw__ZHASH 16384 809 | 810 | #endif // STBIW_ZLIB_COMPRESS 811 | 812 | unsigned char * stbi_zlib_compress(unsigned char *data, int data_len, int *out_len, int quality) 813 | { 814 | #ifdef STBIW_ZLIB_COMPRESS 815 | // user provided a zlib compress implementation, use that 816 | return STBIW_ZLIB_COMPRESS(data, data_len, out_len, quality); 817 | #else // use builtin 818 | 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 }; 819 | 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 }; 820 | 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 }; 821 | 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 }; 822 | unsigned int bitbuf=0; 823 | int i,j, bitcount=0; 824 | unsigned char *out = NULL; 825 | unsigned char ***hash_table = (unsigned char***) STBIW_MALLOC(stbiw__ZHASH * sizeof(char**)); 826 | if (hash_table == NULL) 827 | return NULL; 828 | if (quality < 5) quality = 5; 829 | 830 | stbiw__sbpush(out, 0x78); // DEFLATE 32K window 831 | stbiw__sbpush(out, 0x5e); // FLEVEL = 1 832 | stbiw__zlib_add(1,1); // BFINAL = 1 833 | stbiw__zlib_add(1,2); // BTYPE = 1 -- fixed huffman 834 | 835 | for (i=0; i < stbiw__ZHASH; ++i) 836 | hash_table[i] = NULL; 837 | 838 | i=0; 839 | while (i < data_len-3) { 840 | // hash next 3 bytes of data to be compressed 841 | int h = stbiw__zhash(data+i)&(stbiw__ZHASH-1), best=3; 842 | unsigned char *bestloc = 0; 843 | unsigned char **hlist = hash_table[h]; 844 | int n = stbiw__sbcount(hlist); 845 | for (j=0; j < n; ++j) { 846 | if (hlist[j]-data > i-32768) { // if entry lies within window 847 | int d = stbiw__zlib_countm(hlist[j], data+i, data_len-i); 848 | if (d >= best) best=d,bestloc=hlist[j]; 849 | } 850 | } 851 | // when hash table entry is too long, delete half the entries 852 | if (hash_table[h] && stbiw__sbn(hash_table[h]) == 2*quality) { 853 | STBIW_MEMMOVE(hash_table[h], hash_table[h]+quality, sizeof(hash_table[h][0])*quality); 854 | stbiw__sbn(hash_table[h]) = quality; 855 | } 856 | stbiw__sbpush(hash_table[h],data+i); 857 | 858 | if (bestloc) { 859 | // "lazy matching" - check match at *next* byte, and if it's better, do cur byte as literal 860 | h = stbiw__zhash(data+i+1)&(stbiw__ZHASH-1); 861 | hlist = hash_table[h]; 862 | n = stbiw__sbcount(hlist); 863 | for (j=0; j < n; ++j) { 864 | if (hlist[j]-data > i-32767) { 865 | int e = stbiw__zlib_countm(hlist[j], data+i+1, data_len-i-1); 866 | if (e > best) { // if next match is better, bail on current match 867 | bestloc = NULL; 868 | break; 869 | } 870 | } 871 | } 872 | } 873 | 874 | if (bestloc) { 875 | int d = (int) (data+i - bestloc); // distance back 876 | STBIW_ASSERT(d <= 32767 && best <= 258); 877 | for (j=0; best > lengthc[j+1]-1; ++j); 878 | stbiw__zlib_huff(j+257); 879 | if (lengtheb[j]) stbiw__zlib_add(best - lengthc[j], lengtheb[j]); 880 | for (j=0; d > distc[j+1]-1; ++j); 881 | stbiw__zlib_add(stbiw__zlib_bitrev(j,5),5); 882 | if (disteb[j]) stbiw__zlib_add(d - distc[j], disteb[j]); 883 | i += best; 884 | } else { 885 | stbiw__zlib_huffb(data[i]); 886 | ++i; 887 | } 888 | } 889 | // write out final bytes 890 | for (;i < data_len; ++i) 891 | stbiw__zlib_huffb(data[i]); 892 | stbiw__zlib_huff(256); // end of block 893 | // pad with 0 bits to byte boundary 894 | while (bitcount) 895 | stbiw__zlib_add(0,1); 896 | 897 | for (i=0; i < stbiw__ZHASH; ++i) 898 | (void) stbiw__sbfree(hash_table[i]); 899 | STBIW_FREE(hash_table); 900 | 901 | { 902 | // compute adler32 on input 903 | unsigned int s1=1, s2=0; 904 | int blocklen = (int) (data_len % 5552); 905 | j=0; 906 | while (j < data_len) { 907 | for (i=0; i < blocklen; ++i) s1 += data[j+i], s2 += s1; 908 | s1 %= 65521, s2 %= 65521; 909 | j += blocklen; 910 | blocklen = 5552; 911 | } 912 | stbiw__sbpush(out, STBIW_UCHAR(s2 >> 8)); 913 | stbiw__sbpush(out, STBIW_UCHAR(s2)); 914 | stbiw__sbpush(out, STBIW_UCHAR(s1 >> 8)); 915 | stbiw__sbpush(out, STBIW_UCHAR(s1)); 916 | } 917 | *out_len = stbiw__sbn(out); 918 | // make returned pointer freeable 919 | STBIW_MEMMOVE(stbiw__sbraw(out), out, *out_len); 920 | return (unsigned char *) stbiw__sbraw(out); 921 | #endif // STBIW_ZLIB_COMPRESS 922 | } 923 | 924 | static unsigned int stbiw__crc32(unsigned char *buffer, int len) 925 | { 926 | static unsigned int crc_table[256] = 927 | { 928 | 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3, 929 | 0x0eDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 930 | 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 931 | 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 932 | 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 933 | 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 934 | 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, 935 | 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 936 | 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, 937 | 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01, 938 | 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 939 | 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 940 | 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 941 | 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 942 | 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, 943 | 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 944 | 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 945 | 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 946 | 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7, 947 | 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 948 | 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 949 | 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 950 | 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 951 | 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, 952 | 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713, 953 | 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 954 | 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, 955 | 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 956 | 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 957 | 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 958 | 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, 959 | 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D 960 | }; 961 | 962 | unsigned int crc = ~0u; 963 | int i; 964 | for (i=0; i < len; ++i) 965 | crc = (crc >> 8) ^ crc_table[buffer[i] ^ (crc & 0xff)]; 966 | return ~crc; 967 | } 968 | 969 | #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) 970 | #define stbiw__wp32(data,v) stbiw__wpng4(data, (v)>>24,(v)>>16,(v)>>8,(v)); 971 | #define stbiw__wptag(data,s) stbiw__wpng4(data, s[0],s[1],s[2],s[3]) 972 | 973 | static void stbiw__wpcrc(unsigned char **data, int len) 974 | { 975 | unsigned int crc = stbiw__crc32(*data - len - 4, len+4); 976 | stbiw__wp32(*data, crc); 977 | } 978 | 979 | static unsigned char stbiw__paeth(int a, int b, int c) 980 | { 981 | int p = a + b - c, pa = abs(p-a), pb = abs(p-b), pc = abs(p-c); 982 | if (pa <= pb && pa <= pc) return STBIW_UCHAR(a); 983 | if (pb <= pc) return STBIW_UCHAR(b); 984 | return STBIW_UCHAR(c); 985 | } 986 | 987 | // @OPTIMIZE: provide an option that always forces left-predict or paeth predict 988 | 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) 989 | { 990 | static int mapping[] = { 0,1,2,3,4 }; 991 | static int firstmap[] = { 0,1,0,5,6 }; 992 | int *mymap = (y != 0) ? mapping : firstmap; 993 | int i; 994 | int type = mymap[filter_type]; 995 | unsigned char *z = pixels + stride_bytes * (stbi__flip_vertically_on_write ? height-1-y : y); 996 | int signed_stride = stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes; 997 | for (i = 0; i < n; ++i) { 998 | switch (type) { 999 | case 0: line_buffer[i] = z[i]; break; 1000 | case 1: line_buffer[i] = z[i]; break; 1001 | case 2: line_buffer[i] = z[i] - z[i-signed_stride]; break; 1002 | case 3: line_buffer[i] = z[i] - (z[i-signed_stride]>>1); break; 1003 | case 4: line_buffer[i] = (signed char) (z[i] - stbiw__paeth(0,z[i-signed_stride],0)); break; 1004 | case 5: line_buffer[i] = z[i]; break; 1005 | case 6: line_buffer[i] = z[i]; break; 1006 | } 1007 | } 1008 | for (i=n; i < width*n; ++i) { 1009 | switch (type) { 1010 | case 0: line_buffer[i] = z[i]; break; 1011 | case 1: line_buffer[i] = z[i] - z[i-n]; break; 1012 | case 2: line_buffer[i] = z[i] - z[i-signed_stride]; break; 1013 | case 3: line_buffer[i] = z[i] - ((z[i-n] + z[i-signed_stride])>>1); break; 1014 | case 4: line_buffer[i] = z[i] - stbiw__paeth(z[i-n], z[i-signed_stride], z[i-signed_stride-n]); break; 1015 | case 5: line_buffer[i] = z[i] - (z[i-n]>>1); break; 1016 | case 6: line_buffer[i] = z[i] - stbiw__paeth(z[i-n], 0,0); break; 1017 | } 1018 | } 1019 | } 1020 | 1021 | unsigned char *stbi_write_png_to_mem(unsigned char *pixels, int stride_bytes, int x, int y, int n, int *out_len) 1022 | { 1023 | int force_filter = stbi_write_force_png_filter; 1024 | int ctype[5] = { -1, 0, 4, 2, 6 }; 1025 | unsigned char sig[8] = { 137,80,78,71,13,10,26,10 }; 1026 | unsigned char *out,*o, *filt, *zlib; 1027 | signed char *line_buffer; 1028 | int j,zlen; 1029 | 1030 | if (stride_bytes == 0) 1031 | stride_bytes = x * n; 1032 | 1033 | if (force_filter >= 5) { 1034 | force_filter = -1; 1035 | } 1036 | 1037 | filt = (unsigned char *) STBIW_MALLOC((x*n+1) * y); if (!filt) return 0; 1038 | line_buffer = (signed char *) STBIW_MALLOC(x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; } 1039 | for (j=0; j < y; ++j) { 1040 | int filter_type; 1041 | if (force_filter > -1) { 1042 | filter_type = force_filter; 1043 | stbiw__encode_png_line(pixels, stride_bytes, x, y, j, n, force_filter, line_buffer); 1044 | } else { // Estimate the best filter by running through all of them: 1045 | int best_filter = 0, best_filter_val = 0x7fffffff, est, i; 1046 | for (filter_type = 0; filter_type < 5; filter_type++) { 1047 | stbiw__encode_png_line(pixels, stride_bytes, x, y, j, n, filter_type, line_buffer); 1048 | 1049 | // Estimate the entropy of the line using this filter; the less, the better. 1050 | est = 0; 1051 | for (i = 0; i < x*n; ++i) { 1052 | est += abs((signed char) line_buffer[i]); 1053 | } 1054 | if (est < best_filter_val) { 1055 | best_filter_val = est; 1056 | best_filter = filter_type; 1057 | } 1058 | } 1059 | if (filter_type != best_filter) { // If the last iteration already got us the best filter, don't redo it 1060 | stbiw__encode_png_line(pixels, stride_bytes, x, y, j, n, best_filter, line_buffer); 1061 | filter_type = best_filter; 1062 | } 1063 | } 1064 | // when we get here, filter_type contains the filter type, and line_buffer contains the data 1065 | filt[j*(x*n+1)] = (unsigned char) filter_type; 1066 | STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, x*n); 1067 | } 1068 | STBIW_FREE(line_buffer); 1069 | zlib = stbi_zlib_compress(filt, y*( x*n+1), &zlen, stbi_write_png_compression_level); 1070 | STBIW_FREE(filt); 1071 | if (!zlib) return 0; 1072 | 1073 | // each tag requires 12 bytes of overhead 1074 | out = (unsigned char *) STBIW_MALLOC(8 + 12+13 + 12+zlen + 12); 1075 | if (!out) return 0; 1076 | *out_len = 8 + 12+13 + 12+zlen + 12; 1077 | 1078 | o=out; 1079 | STBIW_MEMMOVE(o,sig,8); o+= 8; 1080 | stbiw__wp32(o, 13); // header length 1081 | stbiw__wptag(o, "IHDR"); 1082 | stbiw__wp32(o, x); 1083 | stbiw__wp32(o, y); 1084 | *o++ = 8; 1085 | *o++ = STBIW_UCHAR(ctype[n]); 1086 | *o++ = 0; 1087 | *o++ = 0; 1088 | *o++ = 0; 1089 | stbiw__wpcrc(&o,13); 1090 | 1091 | stbiw__wp32(o, zlen); 1092 | stbiw__wptag(o, "IDAT"); 1093 | STBIW_MEMMOVE(o, zlib, zlen); 1094 | o += zlen; 1095 | STBIW_FREE(zlib); 1096 | stbiw__wpcrc(&o, zlen); 1097 | 1098 | stbiw__wp32(o,0); 1099 | stbiw__wptag(o, "IEND"); 1100 | stbiw__wpcrc(&o,0); 1101 | 1102 | STBIW_ASSERT(o == out + *out_len); 1103 | 1104 | return out; 1105 | } 1106 | 1107 | #ifndef STBI_WRITE_NO_STDIO 1108 | STBIWDEF int stbi_write_png(char const *filename, int x, int y, int comp, const void *data, int stride_bytes) 1109 | { 1110 | FILE *f; 1111 | int len; 1112 | unsigned char *png = stbi_write_png_to_mem((unsigned char *) data, stride_bytes, x, y, comp, &len); 1113 | if (png == NULL) return 0; 1114 | #ifdef STBI_MSC_SECURE_CRT 1115 | if (fopen_s(&f, filename, "wb")) 1116 | f = NULL; 1117 | #else 1118 | f = fopen(filename, "wb"); 1119 | #endif 1120 | if (!f) { STBIW_FREE(png); return 0; } 1121 | fwrite(png, 1, len, f); 1122 | fclose(f); 1123 | STBIW_FREE(png); 1124 | return 1; 1125 | } 1126 | #endif 1127 | 1128 | 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) 1129 | { 1130 | int len; 1131 | unsigned char *png = stbi_write_png_to_mem((unsigned char *) data, stride_bytes, x, y, comp, &len); 1132 | if (png == NULL) return 0; 1133 | func(context, png, len); 1134 | STBIW_FREE(png); 1135 | return 1; 1136 | } 1137 | 1138 | 1139 | /* *************************************************************************** 1140 | * 1141 | * JPEG writer 1142 | * 1143 | * This is based on Jon Olick's jo_jpeg.cpp: 1144 | * public domain Simple, Minimalistic JPEG writer - http://www.jonolick.com/code.html 1145 | */ 1146 | 1147 | 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, 1148 | 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 }; 1149 | 1150 | static void stbiw__jpg_writeBits(stbi__write_context *s, int *bitBufP, int *bitCntP, const unsigned short *bs) { 1151 | int bitBuf = *bitBufP, bitCnt = *bitCntP; 1152 | bitCnt += bs[1]; 1153 | bitBuf |= bs[0] << (24 - bitCnt); 1154 | while(bitCnt >= 8) { 1155 | unsigned char c = (bitBuf >> 16) & 255; 1156 | stbiw__putc(s, c); 1157 | if(c == 255) { 1158 | stbiw__putc(s, 0); 1159 | } 1160 | bitBuf <<= 8; 1161 | bitCnt -= 8; 1162 | } 1163 | *bitBufP = bitBuf; 1164 | *bitCntP = bitCnt; 1165 | } 1166 | 1167 | static void stbiw__jpg_DCT(float *d0p, float *d1p, float *d2p, float *d3p, float *d4p, float *d5p, float *d6p, float *d7p) { 1168 | float d0 = *d0p, d1 = *d1p, d2 = *d2p, d3 = *d3p, d4 = *d4p, d5 = *d5p, d6 = *d6p, d7 = *d7p; 1169 | float z1, z2, z3, z4, z5, z11, z13; 1170 | 1171 | float tmp0 = d0 + d7; 1172 | float tmp7 = d0 - d7; 1173 | float tmp1 = d1 + d6; 1174 | float tmp6 = d1 - d6; 1175 | float tmp2 = d2 + d5; 1176 | float tmp5 = d2 - d5; 1177 | float tmp3 = d3 + d4; 1178 | float tmp4 = d3 - d4; 1179 | 1180 | // Even part 1181 | float tmp10 = tmp0 + tmp3; // phase 2 1182 | float tmp13 = tmp0 - tmp3; 1183 | float tmp11 = tmp1 + tmp2; 1184 | float tmp12 = tmp1 - tmp2; 1185 | 1186 | d0 = tmp10 + tmp11; // phase 3 1187 | d4 = tmp10 - tmp11; 1188 | 1189 | z1 = (tmp12 + tmp13) * 0.707106781f; // c4 1190 | d2 = tmp13 + z1; // phase 5 1191 | d6 = tmp13 - z1; 1192 | 1193 | // Odd part 1194 | tmp10 = tmp4 + tmp5; // phase 2 1195 | tmp11 = tmp5 + tmp6; 1196 | tmp12 = tmp6 + tmp7; 1197 | 1198 | // The rotator is modified from fig 4-8 to avoid extra negations. 1199 | z5 = (tmp10 - tmp12) * 0.382683433f; // c6 1200 | z2 = tmp10 * 0.541196100f + z5; // c2-c6 1201 | z4 = tmp12 * 1.306562965f + z5; // c2+c6 1202 | z3 = tmp11 * 0.707106781f; // c4 1203 | 1204 | z11 = tmp7 + z3; // phase 5 1205 | z13 = tmp7 - z3; 1206 | 1207 | *d5p = z13 + z2; // phase 6 1208 | *d3p = z13 - z2; 1209 | *d1p = z11 + z4; 1210 | *d7p = z11 - z4; 1211 | 1212 | *d0p = d0; *d2p = d2; *d4p = d4; *d6p = d6; 1213 | } 1214 | 1215 | static void stbiw__jpg_calcBits(int val, unsigned short bits[2]) { 1216 | int tmp1 = val < 0 ? -val : val; 1217 | val = val < 0 ? val-1 : val; 1218 | bits[1] = 1; 1219 | while(tmp1 >>= 1) { 1220 | ++bits[1]; 1221 | } 1222 | bits[0] = val & ((1<0)&&(DU[end0pos]==0); --end0pos) { 1260 | } 1261 | // end0pos = first element in reverse order !=0 1262 | if(end0pos == 0) { 1263 | stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB); 1264 | return DU[0]; 1265 | } 1266 | for(i = 1; i <= end0pos; ++i) { 1267 | int startpos = i; 1268 | int nrzeroes; 1269 | unsigned short bits[2]; 1270 | for (; DU[i]==0 && i<=end0pos; ++i) { 1271 | } 1272 | nrzeroes = i-startpos; 1273 | if ( nrzeroes >= 16 ) { 1274 | int lng = nrzeroes>>4; 1275 | int nrmarker; 1276 | for (nrmarker=1; nrmarker <= lng; ++nrmarker) 1277 | stbiw__jpg_writeBits(s, bitBuf, bitCnt, M16zeroes); 1278 | nrzeroes &= 15; 1279 | } 1280 | stbiw__jpg_calcBits(DU[i], bits); 1281 | stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTAC[(nrzeroes<<4)+bits[1]]); 1282 | stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits); 1283 | } 1284 | if(end0pos != 63) { 1285 | stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB); 1286 | } 1287 | return DU[0]; 1288 | } 1289 | 1290 | static int stbi_write_jpg_core(stbi__write_context *s, int width, int height, int comp, const void* data, int quality) { 1291 | // Constants that don't pollute global namespace 1292 | 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}; 1293 | static const unsigned char std_dc_luminance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11}; 1294 | 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}; 1295 | static const unsigned char std_ac_luminance_values[] = { 1296 | 0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,0x21,0x31,0x41,0x06,0x13,0x51,0x61,0x07,0x22,0x71,0x14,0x32,0x81,0x91,0xa1,0x08, 1297 | 0x23,0x42,0xb1,0xc1,0x15,0x52,0xd1,0xf0,0x24,0x33,0x62,0x72,0x82,0x09,0x0a,0x16,0x17,0x18,0x19,0x1a,0x25,0x26,0x27,0x28, 1298 | 0x29,0x2a,0x34,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,0x59, 1299 | 0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x83,0x84,0x85,0x86,0x87,0x88,0x89, 1300 | 0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,0xb5,0xb6, 1301 | 0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,0xe1,0xe2, 1302 | 0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa 1303 | }; 1304 | 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}; 1305 | static const unsigned char std_dc_chrominance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11}; 1306 | 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}; 1307 | static const unsigned char std_ac_chrominance_values[] = { 1308 | 0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,0x31,0x06,0x12,0x41,0x51,0x07,0x61,0x71,0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91, 1309 | 0xa1,0xb1,0xc1,0x09,0x23,0x33,0x52,0xf0,0x15,0x62,0x72,0xd1,0x0a,0x16,0x24,0x34,0xe1,0x25,0xf1,0x17,0x18,0x19,0x1a,0x26, 1310 | 0x27,0x28,0x29,0x2a,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58, 1311 | 0x59,0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x82,0x83,0x84,0x85,0x86,0x87, 1312 | 0x88,0x89,0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4, 1313 | 0xb5,0xb6,0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda, 1314 | 0xe2,0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa 1315 | }; 1316 | // Huffman tables 1317 | 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}}; 1318 | 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}}; 1319 | static const unsigned short YAC_HT[256][2] = { 1320 | {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}, 1321 | {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}, 1322 | {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}, 1323 | {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}, 1324 | {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}, 1325 | {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}, 1326 | {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}, 1327 | {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}, 1328 | {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}, 1329 | {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}, 1330 | {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}, 1331 | {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}, 1332 | {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}, 1333 | {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}, 1334 | {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}, 1335 | {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} 1336 | }; 1337 | static const unsigned short UVAC_HT[256][2] = { 1338 | {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}, 1339 | {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}, 1340 | {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}, 1341 | {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}, 1342 | {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}, 1343 | {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}, 1344 | {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}, 1345 | {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}, 1346 | {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}, 1347 | {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}, 1348 | {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}, 1349 | {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}, 1350 | {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}, 1351 | {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}, 1352 | {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}, 1353 | {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} 1354 | }; 1355 | 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, 1356 | 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}; 1357 | 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, 1358 | 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}; 1359 | static const float aasf[] = { 1.0f * 2.828427125f, 1.387039845f * 2.828427125f, 1.306562965f * 2.828427125f, 1.175875602f * 2.828427125f, 1360 | 1.0f * 2.828427125f, 0.785694958f * 2.828427125f, 0.541196100f * 2.828427125f, 0.275899379f * 2.828427125f }; 1361 | 1362 | int row, col, i, k; 1363 | float fdtbl_Y[64], fdtbl_UV[64]; 1364 | unsigned char YTable[64], UVTable[64]; 1365 | 1366 | if(!data || !width || !height || comp > 4 || comp < 1) { 1367 | return 0; 1368 | } 1369 | 1370 | quality = quality ? quality : 90; 1371 | quality = quality < 1 ? 1 : quality > 100 ? 100 : quality; 1372 | quality = quality < 50 ? 5000 / quality : 200 - quality * 2; 1373 | 1374 | for(i = 0; i < 64; ++i) { 1375 | int uvti, yti = (YQT[i]*quality+50)/100; 1376 | YTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (yti < 1 ? 1 : yti > 255 ? 255 : yti); 1377 | uvti = (UVQT[i]*quality+50)/100; 1378 | UVTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (uvti < 1 ? 1 : uvti > 255 ? 255 : uvti); 1379 | } 1380 | 1381 | for(row = 0, k = 0; row < 8; ++row) { 1382 | for(col = 0; col < 8; ++col, ++k) { 1383 | fdtbl_Y[k] = 1 / (YTable [stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]); 1384 | fdtbl_UV[k] = 1 / (UVTable[stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]); 1385 | } 1386 | } 1387 | 1388 | // Write Headers 1389 | { 1390 | 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 }; 1391 | static const unsigned char head2[] = { 0xFF,0xDA,0,0xC,3,1,0,2,0x11,3,0x11,0,0x3F,0 }; 1392 | const unsigned char head1[] = { 0xFF,0xC0,0,0x11,8,(unsigned char)(height>>8),STBIW_UCHAR(height),(unsigned char)(width>>8),STBIW_UCHAR(width), 1393 | 3,1,0x11,0,2,0x11,1,3,0x11,1,0xFF,0xC4,0x01,0xA2,0 }; 1394 | s->func(s->context, (void*)head0, sizeof(head0)); 1395 | s->func(s->context, (void*)YTable, sizeof(YTable)); 1396 | stbiw__putc(s, 1); 1397 | s->func(s->context, UVTable, sizeof(UVTable)); 1398 | s->func(s->context, (void*)head1, sizeof(head1)); 1399 | s->func(s->context, (void*)(std_dc_luminance_nrcodes+1), sizeof(std_dc_luminance_nrcodes)-1); 1400 | s->func(s->context, (void*)std_dc_luminance_values, sizeof(std_dc_luminance_values)); 1401 | stbiw__putc(s, 0x10); // HTYACinfo 1402 | s->func(s->context, (void*)(std_ac_luminance_nrcodes+1), sizeof(std_ac_luminance_nrcodes)-1); 1403 | s->func(s->context, (void*)std_ac_luminance_values, sizeof(std_ac_luminance_values)); 1404 | stbiw__putc(s, 1); // HTUDCinfo 1405 | s->func(s->context, (void*)(std_dc_chrominance_nrcodes+1), sizeof(std_dc_chrominance_nrcodes)-1); 1406 | s->func(s->context, (void*)std_dc_chrominance_values, sizeof(std_dc_chrominance_values)); 1407 | stbiw__putc(s, 0x11); // HTUACinfo 1408 | s->func(s->context, (void*)(std_ac_chrominance_nrcodes+1), sizeof(std_ac_chrominance_nrcodes)-1); 1409 | s->func(s->context, (void*)std_ac_chrominance_values, sizeof(std_ac_chrominance_values)); 1410 | s->func(s->context, (void*)head2, sizeof(head2)); 1411 | } 1412 | 1413 | // Encode 8x8 macroblocks 1414 | { 1415 | static const unsigned short fillBits[] = {0x7F, 7}; 1416 | const unsigned char *imageData = (const unsigned char *)data; 1417 | int DCY=0, DCU=0, DCV=0; 1418 | int bitBuf=0, bitCnt=0; 1419 | // comp == 2 is grey+alpha (alpha is ignored) 1420 | int ofsG = comp > 2 ? 1 : 0, ofsB = comp > 2 ? 2 : 0; 1421 | int x, y, pos; 1422 | for(y = 0; y < height; y += 8) { 1423 | for(x = 0; x < width; x += 8) { 1424 | float YDU[64], UDU[64], VDU[64]; 1425 | for(row = y, pos = 0; row < y+8; ++row) { 1426 | for(col = x; col < x+8; ++col, ++pos) { 1427 | int p = (stbi__flip_vertically_on_write ? height-1-row : row)*width*comp + col*comp; 1428 | float r, g, b; 1429 | if(row >= height) { 1430 | p -= width*comp*(row+1 - height); 1431 | } 1432 | if(col >= width) { 1433 | p -= comp*(col+1 - width); 1434 | } 1435 | 1436 | r = imageData[p+0]; 1437 | g = imageData[p+ofsG]; 1438 | b = imageData[p+ofsB]; 1439 | YDU[pos]=+0.29900f*r+0.58700f*g+0.11400f*b-128; 1440 | UDU[pos]=-0.16874f*r-0.33126f*g+0.50000f*b; 1441 | VDU[pos]=+0.50000f*r-0.41869f*g-0.08131f*b; 1442 | } 1443 | } 1444 | 1445 | DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, YDU, fdtbl_Y, DCY, YDC_HT, YAC_HT); 1446 | DCU = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, UDU, fdtbl_UV, DCU, UVDC_HT, UVAC_HT); 1447 | DCV = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, VDU, fdtbl_UV, DCV, UVDC_HT, UVAC_HT); 1448 | } 1449 | } 1450 | 1451 | // Do the bit alignment of the EOI marker 1452 | stbiw__jpg_writeBits(s, &bitBuf, &bitCnt, fillBits); 1453 | } 1454 | 1455 | // EOI 1456 | stbiw__putc(s, 0xFF); 1457 | stbiw__putc(s, 0xD9); 1458 | 1459 | return 1; 1460 | } 1461 | 1462 | STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality) 1463 | { 1464 | stbi__write_context s; 1465 | stbi__start_write_callbacks(&s, func, context); 1466 | return stbi_write_jpg_core(&s, x, y, comp, (void *) data, quality); 1467 | } 1468 | 1469 | 1470 | #ifndef STBI_WRITE_NO_STDIO 1471 | STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality) 1472 | { 1473 | stbi__write_context s; 1474 | if (stbi__start_write_file(&s,filename)) { 1475 | int r = stbi_write_jpg_core(&s, x, y, comp, data, quality); 1476 | stbi__end_write_file(&s); 1477 | return r; 1478 | } else 1479 | return 0; 1480 | } 1481 | #endif 1482 | 1483 | #endif // STB_IMAGE_WRITE_IMPLEMENTATION 1484 | 1485 | /* Revision history 1486 | 1.09 (2018-02-11) 1487 | fix typo in zlib quality API, improve STB_I_W_STATIC in C++ 1488 | 1.08 (2018-01-29) 1489 | add stbi__flip_vertically_on_write, external zlib, zlib quality, choose PNG filter 1490 | 1.07 (2017-07-24) 1491 | doc fix 1492 | 1.06 (2017-07-23) 1493 | writing JPEG (using Jon Olick's code) 1494 | 1.05 ??? 1495 | 1.04 (2017-03-03) 1496 | monochrome BMP expansion 1497 | 1.03 ??? 1498 | 1.02 (2016-04-02) 1499 | avoid allocating large structures on the stack 1500 | 1.01 (2016-01-16) 1501 | STBIW_REALLOC_SIZED: support allocators with no realloc support 1502 | avoid race-condition in crc initialization 1503 | minor compile issues 1504 | 1.00 (2015-09-14) 1505 | installable file IO function 1506 | 0.99 (2015-09-13) 1507 | warning fixes; TGA rle support 1508 | 0.98 (2015-04-08) 1509 | added STBIW_MALLOC, STBIW_ASSERT etc 1510 | 0.97 (2015-01-18) 1511 | fixed HDR asserts, rewrote HDR rle logic 1512 | 0.96 (2015-01-17) 1513 | add HDR output 1514 | fix monochrome BMP 1515 | 0.95 (2014-08-17) 1516 | add monochrome TGA output 1517 | 0.94 (2014-05-31) 1518 | rename private functions to avoid conflicts with stb_image.h 1519 | 0.93 (2014-05-27) 1520 | warning fixes 1521 | 0.92 (2010-08-01) 1522 | casts to unsigned char to fix warnings 1523 | 0.91 (2010-07-17) 1524 | first public release 1525 | 0.90 first internal release 1526 | */ 1527 | 1528 | /* 1529 | ------------------------------------------------------------------------------ 1530 | This software is available under 2 licenses -- choose whichever you prefer. 1531 | ------------------------------------------------------------------------------ 1532 | ALTERNATIVE A - MIT License 1533 | Copyright (c) 2017 Sean Barrett 1534 | Permission is hereby granted, free of charge, to any person obtaining a copy of 1535 | this software and associated documentation files (the "Software"), to deal in 1536 | the Software without restriction, including without limitation the rights to 1537 | use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 1538 | of the Software, and to permit persons to whom the Software is furnished to do 1539 | so, subject to the following conditions: 1540 | The above copyright notice and this permission notice shall be included in all 1541 | copies or substantial portions of the Software. 1542 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 1543 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 1544 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 1545 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 1546 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 1547 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 1548 | SOFTWARE. 1549 | ------------------------------------------------------------------------------ 1550 | ALTERNATIVE B - Public Domain (www.unlicense.org) 1551 | This is free and unencumbered software released into the public domain. 1552 | Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 1553 | software, either in source code form or as a compiled binary, for any purpose, 1554 | commercial or non-commercial, and by any means. 1555 | In jurisdictions that recognize copyright laws, the author or authors of this 1556 | software dedicate any and all copyright interest in the software to the public 1557 | domain. We make this dedication for the benefit of the public at large and to 1558 | the detriment of our heirs and successors. We intend this dedication to be an 1559 | overt act of relinquishment in perpetuity of all present and future rights to 1560 | this software under copyright law. 1561 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 1562 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 1563 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 1564 | AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 1565 | ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 1566 | WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 1567 | ------------------------------------------------------------------------------ 1568 | */ 1569 | --------------------------------------------------------------------------------