1 /* 2 * jccolor.c 3 * 4 * Copyright (C) 1991-1996, Thomas G. Lane. 5 * This file is part of the Independent JPEG Group's software. 6 * For conditions of distribution and use, see the accompanying README file. 7 * 8 * This file contains input colorspace conversion routines. 9 */ 10 11 #define JPEG_INTERNALS 12 #include "jinclude.h" 13 #include "jpeglib.h" 14 15 // this enables unrolling null_convert's loop, and reading/write ints for speed 16 #define ENABLE_ANDROID_NULL_CONVERT 17 18 /* Private subobject */ 19 20 typedef struct { 21 struct jpeg_color_converter pub; /* public fields */ 22 23 /* Private state for RGB->YCC conversion */ 24 INT32 * rgb_ycc_tab; /* => table for RGB to YCbCr conversion */ 25 } my_color_converter; 26 27 typedef my_color_converter * my_cconvert_ptr; 28 29 30 /**************** RGB -> YCbCr conversion: most common case **************/ 31 32 /* 33 * YCbCr is defined per CCIR 601-1, except that Cb and Cr are 34 * normalized to the range 0..MAXJSAMPLE rather than -0.5 .. 0.5. 35 * The conversion equations to be implemented are therefore 36 * Y = 0.29900 * R + 0.58700 * G + 0.11400 * B 37 * Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B + CENTERJSAMPLE 38 * Cr = 0.50000 * R - 0.41869 * G - 0.08131 * B + CENTERJSAMPLE 39 * (These numbers are derived from TIFF 6.0 section 21, dated 3-June-92.) 40 * Note: older versions of the IJG code used a zero offset of MAXJSAMPLE/2, 41 * rather than CENTERJSAMPLE, for Cb and Cr. This gave equal positive and 42 * negative swings for Cb/Cr, but meant that grayscale values (Cb=Cr=0) 43 * were not represented exactly. Now we sacrifice exact representation of 44 * maximum red and maximum blue in order to get exact grayscales. 45 * 46 * To avoid floating-point arithmetic, we represent the fractional constants 47 * as integers scaled up by 2^16 (about 4 digits precision); we have to divide 48 * the products by 2^16, with appropriate rounding, to get the correct answer. 49 * 50 * For even more speed, we avoid doing any multiplications in the inner loop 51 * by precalculating the constants times R,G,B for all possible values. 52 * For 8-bit JSAMPLEs this is very reasonable (only 256 entries per table); 53 * for 12-bit samples it is still acceptable. It's not very reasonable for 54 * 16-bit samples, but if you want lossless storage you shouldn't be changing 55 * colorspace anyway. 56 * The CENTERJSAMPLE offsets and the rounding fudge-factor of 0.5 are included 57 * in the tables to save adding them separately in the inner loop. 58 */ 59 60 #define SCALEBITS 16 /* speediest right-shift on some machines */ 61 #define CBCR_OFFSET ((INT32) CENTERJSAMPLE << SCALEBITS) 62 #define ONE_HALF ((INT32) 1 << (SCALEBITS-1)) 63 #define FIX(x) ((INT32) ((x) * (1L<<SCALEBITS) + 0.5)) 64 65 /* We allocate one big table and divide it up into eight parts, instead of 66 * doing eight alloc_small requests. This lets us use a single table base 67 * address, which can be held in a register in the inner loops on many 68 * machines (more than can hold all eight addresses, anyway). 69 */ 70 71 #define R_Y_OFF 0 /* offset to R => Y section */ 72 #define G_Y_OFF (1*(MAXJSAMPLE+1)) /* offset to G => Y section */ 73 #define B_Y_OFF (2*(MAXJSAMPLE+1)) /* etc. */ 74 #define R_CB_OFF (3*(MAXJSAMPLE+1)) 75 #define G_CB_OFF (4*(MAXJSAMPLE+1)) 76 #define B_CB_OFF (5*(MAXJSAMPLE+1)) 77 #define R_CR_OFF B_CB_OFF /* B=>Cb, R=>Cr are the same */ 78 #define G_CR_OFF (6*(MAXJSAMPLE+1)) 79 #define B_CR_OFF (7*(MAXJSAMPLE+1)) 80 #define TABLE_SIZE (8*(MAXJSAMPLE+1)) 81 82 83 /* 84 * Initialize for RGB->YCC colorspace conversion. 85 */ 86 87 METHODDEF(void) 88 rgb_ycc_start (j_compress_ptr cinfo) 89 { 90 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; 91 INT32 * rgb_ycc_tab; 92 INT32 i; 93 94 /* Allocate and fill in the conversion tables. */ 95 cconvert->rgb_ycc_tab = rgb_ycc_tab = (INT32 *) 96 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 97 (TABLE_SIZE * SIZEOF(INT32))); 98 99 for (i = 0; i <= MAXJSAMPLE; i++) { 100 rgb_ycc_tab[i+R_Y_OFF] = FIX(0.29900) * i; 101 rgb_ycc_tab[i+G_Y_OFF] = FIX(0.58700) * i; 102 rgb_ycc_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF; 103 rgb_ycc_tab[i+R_CB_OFF] = (-FIX(0.16874)) * i; 104 rgb_ycc_tab[i+G_CB_OFF] = (-FIX(0.33126)) * i; 105 /* We use a rounding fudge-factor of 0.5-epsilon for Cb and Cr. 106 * This ensures that the maximum output will round to MAXJSAMPLE 107 * not MAXJSAMPLE+1, and thus that we don't have to range-limit. 108 */ 109 rgb_ycc_tab[i+B_CB_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1; 110 /* B=>Cb and R=>Cr tables are the same 111 rgb_ycc_tab[i+R_CR_OFF] = FIX(0.50000) * i + CBCR_OFFSET + ONE_HALF-1; 112 */ 113 rgb_ycc_tab[i+G_CR_OFF] = (-FIX(0.41869)) * i; 114 rgb_ycc_tab[i+B_CR_OFF] = (-FIX(0.08131)) * i; 115 } 116 } 117 118 119 /* 120 * Convert some rows of samples to the JPEG colorspace. 121 * 122 * Note that we change from the application's interleaved-pixel format 123 * to our internal noninterleaved, one-plane-per-component format. 124 * The input buffer is therefore three times as wide as the output buffer. 125 * 126 * A starting row offset is provided only for the output buffer. The caller 127 * can easily adjust the passed input_buf value to accommodate any row 128 * offset required on that side. 129 */ 130 131 METHODDEF(void) 132 rgb_ycc_convert (j_compress_ptr cinfo, 133 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 134 JDIMENSION output_row, int num_rows) 135 { 136 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; 137 register int r, g, b; 138 register INT32 * ctab = cconvert->rgb_ycc_tab; 139 register JSAMPROW inptr; 140 register JSAMPROW outptr0, outptr1, outptr2; 141 register JDIMENSION col; 142 JDIMENSION num_cols = cinfo->image_width; 143 144 while (--num_rows >= 0) { 145 inptr = *input_buf++; 146 outptr0 = output_buf[0][output_row]; 147 outptr1 = output_buf[1][output_row]; 148 outptr2 = output_buf[2][output_row]; 149 output_row++; 150 for (col = 0; col < num_cols; col++) { 151 r = GETJSAMPLE(inptr[RGB_RED]); 152 g = GETJSAMPLE(inptr[RGB_GREEN]); 153 b = GETJSAMPLE(inptr[RGB_BLUE]); 154 inptr += RGB_PIXELSIZE; 155 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations 156 * must be too; we do not need an explicit range-limiting operation. 157 * Hence the value being shifted is never negative, and we don't 158 * need the general RIGHT_SHIFT macro. 159 */ 160 /* Y */ 161 outptr0[col] = (JSAMPLE) 162 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) 163 >> SCALEBITS); 164 /* Cb */ 165 outptr1[col] = (JSAMPLE) 166 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF]) 167 >> SCALEBITS); 168 /* Cr */ 169 outptr2[col] = (JSAMPLE) 170 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) 171 >> SCALEBITS); 172 } 173 } 174 } 175 176 #ifdef ANDROID_RGB 177 /* Converts RGB565 row into YCbCr */ 178 METHODDEF(void) 179 rgb565_ycc_convert (j_compress_ptr cinfo, 180 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 181 JDIMENSION output_row, int num_rows) 182 { 183 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; 184 register int r, g, b; 185 register INT32 * ctab = cconvert->rgb_ycc_tab; 186 register unsigned short* inptr; 187 register JSAMPROW outptr0, outptr1, outptr2; 188 register JDIMENSION col; 189 JDIMENSION num_cols = cinfo->image_width; 190 191 while (--num_rows >= 0) { 192 inptr = (unsigned short*)(*input_buf++); 193 outptr0 = output_buf[0][output_row]; 194 outptr1 = output_buf[1][output_row]; 195 outptr2 = output_buf[2][output_row]; 196 output_row++; 197 for (col = 0; col < num_cols; col++) { 198 register const unsigned short color = inptr[col]; 199 r = ((color & 0xf800) >> 8) | ((color & 0xf800) >> 14); 200 g = ((color & 0x7e0) >> 3) | ((color & 0x7e0) >> 9); 201 b = ((color & 0x1f) << 3) | ((color & 0x1f) >> 2); 202 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations 203 * must be too; we do not need an explicit range-limiting operation. 204 * Hence the value being shifted is never negative, and we don't 205 * need the general RIGHT_SHIFT macro. 206 */ 207 /* Y */ 208 outptr0[col] = (JSAMPLE) 209 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) 210 >> SCALEBITS); 211 /* Cb */ 212 outptr1[col] = (JSAMPLE) 213 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF]) 214 >> SCALEBITS); 215 /* Cr */ 216 outptr2[col] = (JSAMPLE) 217 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) 218 >> SCALEBITS); 219 } 220 } 221 } 222 223 /* Converts RGBA8888 row into YCbCr */ 224 METHODDEF(void) 225 rgba8888_ycc_convert (j_compress_ptr cinfo, 226 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 227 JDIMENSION output_row, int num_rows) 228 { 229 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; 230 register int r, g, b; 231 register INT32 * ctab = cconvert->rgb_ycc_tab; 232 register INT32* inptr; 233 register JSAMPROW outptr0, outptr1, outptr2; 234 register JDIMENSION col; 235 JDIMENSION num_cols = cinfo->image_width; 236 237 while (--num_rows >= 0) { 238 inptr = (INT32*)(*input_buf++); 239 outptr0 = output_buf[0][output_row]; 240 outptr1 = output_buf[1][output_row]; 241 outptr2 = output_buf[2][output_row]; 242 output_row++; 243 for (col = 0; col < num_cols; col++) { 244 register const unsigned char* color = (unsigned char*)(inptr + col); 245 r = (*color) & 0xff; color++; 246 g = (*color) & 0xff; color++; 247 b = (*color) & 0xff; color++; 248 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations 249 * must be too; we do not need an explicit range-limiting operation. 250 * Hence the value being shifted is never negative, and we don't 251 * need the general RIGHT_SHIFT macro. 252 */ 253 /* Y */ 254 outptr0[col] = (JSAMPLE) 255 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) 256 >> SCALEBITS); 257 /* Cb */ 258 outptr1[col] = (JSAMPLE) 259 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF]) 260 >> SCALEBITS); 261 /* Cr */ 262 outptr2[col] = (JSAMPLE) 263 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) 264 >> SCALEBITS); 265 } 266 } 267 } 268 #endif /* ANDROID_RGB */ 269 270 /**************** Cases other than RGB -> YCbCr **************/ 271 272 273 /* 274 * Convert some rows of samples to the JPEG colorspace. 275 * This version handles RGB->grayscale conversion, which is the same 276 * as the RGB->Y portion of RGB->YCbCr. 277 * We assume rgb_ycc_start has been called (we only use the Y tables). 278 */ 279 280 METHODDEF(void) 281 rgb_gray_convert (j_compress_ptr cinfo, 282 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 283 JDIMENSION output_row, int num_rows) 284 { 285 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; 286 register int r, g, b; 287 register INT32 * ctab = cconvert->rgb_ycc_tab; 288 register JSAMPROW inptr; 289 register JSAMPROW outptr; 290 register JDIMENSION col; 291 JDIMENSION num_cols = cinfo->image_width; 292 293 while (--num_rows >= 0) { 294 inptr = *input_buf++; 295 outptr = output_buf[0][output_row]; 296 output_row++; 297 for (col = 0; col < num_cols; col++) { 298 r = GETJSAMPLE(inptr[RGB_RED]); 299 g = GETJSAMPLE(inptr[RGB_GREEN]); 300 b = GETJSAMPLE(inptr[RGB_BLUE]); 301 inptr += RGB_PIXELSIZE; 302 /* Y */ 303 outptr[col] = (JSAMPLE) 304 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) 305 >> SCALEBITS); 306 } 307 } 308 } 309 310 311 /* 312 * Convert some rows of samples to the JPEG colorspace. 313 * This version handles Adobe-style CMYK->YCCK conversion, 314 * where we convert R=1-C, G=1-M, and B=1-Y to YCbCr using the same 315 * conversion as above, while passing K (black) unchanged. 316 * We assume rgb_ycc_start has been called. 317 */ 318 319 METHODDEF(void) 320 cmyk_ycck_convert (j_compress_ptr cinfo, 321 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 322 JDIMENSION output_row, int num_rows) 323 { 324 my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert; 325 register int r, g, b; 326 register INT32 * ctab = cconvert->rgb_ycc_tab; 327 register JSAMPROW inptr; 328 register JSAMPROW outptr0, outptr1, outptr2, outptr3; 329 register JDIMENSION col; 330 JDIMENSION num_cols = cinfo->image_width; 331 332 while (--num_rows >= 0) { 333 inptr = *input_buf++; 334 outptr0 = output_buf[0][output_row]; 335 outptr1 = output_buf[1][output_row]; 336 outptr2 = output_buf[2][output_row]; 337 outptr3 = output_buf[3][output_row]; 338 output_row++; 339 for (col = 0; col < num_cols; col++) { 340 r = MAXJSAMPLE - GETJSAMPLE(inptr[0]); 341 g = MAXJSAMPLE - GETJSAMPLE(inptr[1]); 342 b = MAXJSAMPLE - GETJSAMPLE(inptr[2]); 343 /* K passes through as-is */ 344 outptr3[col] = inptr[3]; /* don't need GETJSAMPLE here */ 345 inptr += 4; 346 /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations 347 * must be too; we do not need an explicit range-limiting operation. 348 * Hence the value being shifted is never negative, and we don't 349 * need the general RIGHT_SHIFT macro. 350 */ 351 /* Y */ 352 outptr0[col] = (JSAMPLE) 353 ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF]) 354 >> SCALEBITS); 355 /* Cb */ 356 outptr1[col] = (JSAMPLE) 357 ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF]) 358 >> SCALEBITS); 359 /* Cr */ 360 outptr2[col] = (JSAMPLE) 361 ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF]) 362 >> SCALEBITS); 363 } 364 } 365 } 366 367 368 /* 369 * Convert some rows of samples to the JPEG colorspace. 370 * This version handles grayscale output with no conversion. 371 * The source can be either plain grayscale or YCbCr (since Y == gray). 372 */ 373 374 METHODDEF(void) 375 grayscale_convert (j_compress_ptr cinfo, 376 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 377 JDIMENSION output_row, int num_rows) 378 { 379 register JSAMPROW inptr; 380 register JSAMPROW outptr; 381 register JDIMENSION col; 382 JDIMENSION num_cols = cinfo->image_width; 383 int instride = cinfo->input_components; 384 385 while (--num_rows >= 0) { 386 inptr = *input_buf++; 387 outptr = output_buf[0][output_row]; 388 output_row++; 389 for (col = 0; col < num_cols; col++) { 390 outptr[col] = inptr[0]; /* don't need GETJSAMPLE() here */ 391 inptr += instride; 392 } 393 } 394 } 395 396 #ifdef ENABLE_ANDROID_NULL_CONVERT 397 398 typedef unsigned long UINT32; 399 400 #define B0(n) ((n) & 0xFF) 401 #define B1(n) (((n) >> 8) & 0xFF) 402 #define B2(n) (((n) >> 16) & 0xFF) 403 #define B3(n) ((n) >> 24) 404 405 #define PACK(a, b, c, d) ((a) | ((b) << 8) | ((c) << 16) | ((d) << 24)) 406 407 static int ptr_is_quad(const void* p) 408 { 409 return (((const char*)p - (const char*)0) & 3) == 0; 410 } 411 412 static void copyquads(const UINT32 in[], UINT32 out0[], UINT32 out1[], UINT32 out2[], int col4) 413 { 414 do { 415 UINT32 src0 = *in++; 416 UINT32 src1 = *in++; 417 UINT32 src2 = *in++; 418 // LEndian 419 *out0++ = PACK(B0(src0), B3(src0), B2(src1), B1(src2)); 420 *out1++ = PACK(B1(src0), B0(src1), B3(src1), B2(src2)); 421 *out2++ = PACK(B2(src0), B1(src1), B0(src2), B3(src2)); 422 } while (--col4 != 0); 423 } 424 425 #endif 426 427 /* 428 * Convert some rows of samples to the JPEG colorspace. 429 * This version handles multi-component colorspaces without conversion. 430 * We assume input_components == num_components. 431 */ 432 433 METHODDEF(void) 434 null_convert (j_compress_ptr cinfo, 435 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 436 JDIMENSION output_row, int num_rows) 437 { 438 register JSAMPROW inptr; 439 register JSAMPROW outptr; 440 register JDIMENSION col; 441 register int ci; 442 int nc = cinfo->num_components; 443 JDIMENSION num_cols = cinfo->image_width; 444 445 #ifdef ENABLE_ANDROID_NULL_CONVERT 446 if (1 == num_rows && 3 == nc && num_cols > 0) { 447 JSAMPROW inptr = *input_buf; 448 JSAMPROW outptr0 = output_buf[0][output_row]; 449 JSAMPROW outptr1 = output_buf[1][output_row]; 450 JSAMPROW outptr2 = output_buf[2][output_row]; 451 452 int col = num_cols; 453 int col4 = col >> 2; 454 if (col4 > 0 && ptr_is_quad(inptr) && ptr_is_quad(outptr0) && 455 ptr_is_quad(outptr1) && ptr_is_quad(outptr2)) { 456 457 const UINT32* in = (const UINT32*)inptr; 458 UINT32* out0 = (UINT32*)outptr0; 459 UINT32* out1 = (UINT32*)outptr1; 460 UINT32* out2 = (UINT32*)outptr2; 461 copyquads(in, out0, out1, out2, col4); 462 col &= 3; 463 if (0 == col) 464 return; 465 col4 <<= 2; 466 inptr += col4 * 3; /* we read this 3 times per in copyquads */ 467 outptr0 += col4; 468 outptr1 += col4; 469 outptr2 += col4; 470 /* fall through to while-loop */ 471 } 472 do { 473 *outptr0++ = *inptr++; 474 *outptr1++ = *inptr++; 475 *outptr2++ = *inptr++; 476 } while (--col != 0); 477 return; 478 } 479 SLOW: 480 #endif 481 while (--num_rows >= 0) { 482 /* It seems fastest to make a separate pass for each component. */ 483 for (ci = 0; ci < nc; ci++) { 484 inptr = *input_buf; 485 outptr = output_buf[ci][output_row]; 486 for (col = 0; col < num_cols; col++) { 487 outptr[col] = inptr[ci]; /* don't need GETJSAMPLE() here */ 488 inptr += nc; 489 } 490 } 491 input_buf++; 492 output_row++; 493 } 494 } 495 496 497 /* 498 * Empty method for start_pass. 499 */ 500 501 METHODDEF(void) 502 null_method (j_compress_ptr cinfo) 503 { 504 /* no work needed */ 505 } 506 507 508 /* 509 * Module initialization routine for input colorspace conversion. 510 */ 511 512 GLOBAL(void) 513 jinit_color_converter (j_compress_ptr cinfo) 514 { 515 my_cconvert_ptr cconvert; 516 517 cconvert = (my_cconvert_ptr) 518 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 519 SIZEOF(my_color_converter)); 520 cinfo->cconvert = (struct jpeg_color_converter *) cconvert; 521 /* set start_pass to null method until we find out differently */ 522 cconvert->pub.start_pass = null_method; 523 524 /* Make sure input_components agrees with in_color_space */ 525 switch (cinfo->in_color_space) { 526 case JCS_GRAYSCALE: 527 if (cinfo->input_components != 1) 528 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 529 break; 530 531 case JCS_RGB: 532 #if RGB_PIXELSIZE != 3 533 if (cinfo->input_components != RGB_PIXELSIZE) 534 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 535 break; 536 #endif /* else share code with YCbCr */ 537 538 case JCS_YCbCr: 539 if (cinfo->input_components != 3) 540 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 541 break; 542 543 case JCS_CMYK: 544 case JCS_YCCK: 545 if (cinfo->input_components != 4) 546 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 547 break; 548 549 #ifdef ANDROID_RGB 550 case JCS_RGB_565: 551 if (cinfo->input_components != 2) 552 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 553 break; 554 case JCS_RGBA_8888: 555 if (cinfo->input_components != 4) 556 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 557 break; 558 #endif /* ANDROID_RGB */ 559 560 default: /* JCS_UNKNOWN can be anything */ 561 if (cinfo->input_components < 1) 562 ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE); 563 break; 564 } 565 566 /* Check num_components, set conversion method based on requested space */ 567 switch (cinfo->jpeg_color_space) { 568 case JCS_GRAYSCALE: 569 if (cinfo->num_components != 1) 570 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); 571 if (cinfo->in_color_space == JCS_GRAYSCALE) 572 cconvert->pub.color_convert = grayscale_convert; 573 else if (cinfo->in_color_space == JCS_RGB) { 574 cconvert->pub.start_pass = rgb_ycc_start; 575 cconvert->pub.color_convert = rgb_gray_convert; 576 } else if (cinfo->in_color_space == JCS_YCbCr) 577 cconvert->pub.color_convert = grayscale_convert; 578 else 579 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 580 break; 581 582 case JCS_RGB: 583 if (cinfo->num_components != 3) 584 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); 585 if (cinfo->in_color_space == JCS_RGB && RGB_PIXELSIZE == 3) 586 cconvert->pub.color_convert = null_convert; 587 else 588 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 589 break; 590 591 case JCS_YCbCr: 592 if (cinfo->num_components != 3) 593 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); 594 if (cinfo->in_color_space == JCS_RGB) { 595 cconvert->pub.start_pass = rgb_ycc_start; 596 cconvert->pub.color_convert = rgb_ycc_convert; 597 } else if (cinfo->in_color_space == JCS_YCbCr) { 598 cconvert->pub.color_convert = null_convert; 599 } 600 #ifdef ANDROID_RGB 601 else if (cinfo->in_color_space == JCS_RGB_565) { 602 cconvert->pub.start_pass = rgb_ycc_start; 603 cconvert->pub.color_convert = rgb565_ycc_convert; 604 } else if (cinfo->in_color_space == JCS_RGBA_8888) { 605 cconvert->pub.start_pass = rgb_ycc_start; 606 cconvert->pub.color_convert = rgba8888_ycc_convert; 607 } 608 #endif /* ANDROID_RGB */ 609 else 610 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 611 break; 612 613 case JCS_CMYK: 614 if (cinfo->num_components != 4) 615 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); 616 if (cinfo->in_color_space == JCS_CMYK) 617 cconvert->pub.color_convert = null_convert; 618 else 619 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 620 break; 621 622 case JCS_YCCK: 623 if (cinfo->num_components != 4) 624 ERREXIT(cinfo, JERR_BAD_J_COLORSPACE); 625 if (cinfo->in_color_space == JCS_CMYK) { 626 cconvert->pub.start_pass = rgb_ycc_start; 627 cconvert->pub.color_convert = cmyk_ycck_convert; 628 } else if (cinfo->in_color_space == JCS_YCCK) 629 cconvert->pub.color_convert = null_convert; 630 else 631 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 632 break; 633 634 default: /* allow null conversion of JCS_UNKNOWN */ 635 if (cinfo->jpeg_color_space != cinfo->in_color_space || 636 cinfo->num_components != cinfo->input_components) 637 ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL); 638 cconvert->pub.color_convert = null_convert; 639 break; 640 } 641 } 642
