1/* 2 * Simple IDCT 3 * 4 * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at> 5 * 6 * This file is part of FFmpeg. 7 * 8 * FFmpeg is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * FFmpeg is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with FFmpeg; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23/** 24 * @file libavcodec/simple_idct.c 25 * simpleidct in C. 26 */ 27 28/* 29 based upon some outcommented c code from mpeg2dec (idct_mmx.c 30 written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>) 31 */ 32#include "avcodec.h" 33#include "dsputil.h" 34#include "mathops.h" 35#include "simple_idct.h" 36 37#if 0 38#define W1 2841 /* 2048*sqrt (2)*cos (1*pi/16) */ 39#define W2 2676 /* 2048*sqrt (2)*cos (2*pi/16) */ 40#define W3 2408 /* 2048*sqrt (2)*cos (3*pi/16) */ 41#define W4 2048 /* 2048*sqrt (2)*cos (4*pi/16) */ 42#define W5 1609 /* 2048*sqrt (2)*cos (5*pi/16) */ 43#define W6 1108 /* 2048*sqrt (2)*cos (6*pi/16) */ 44#define W7 565 /* 2048*sqrt (2)*cos (7*pi/16) */ 45#define ROW_SHIFT 8 46#define COL_SHIFT 17 47#else 48#define W1 22725 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 49#define W2 21407 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 50#define W3 19266 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 51#define W4 16383 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 52#define W5 12873 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 53#define W6 8867 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 54#define W7 4520 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 55#define ROW_SHIFT 11 56#define COL_SHIFT 20 // 6 57#endif 58 59static inline void idctRowCondDC (DCTELEM * row) 60{ 61 int a0, a1, a2, a3, b0, b1, b2, b3; 62#if HAVE_FAST_64BIT 63 uint64_t temp; 64#else 65 uint32_t temp; 66#endif 67 68#if HAVE_FAST_64BIT 69#ifdef WORDS_BIGENDIAN 70#define ROW0_MASK 0xffff000000000000LL 71#else 72#define ROW0_MASK 0xffffLL 73#endif 74 if(sizeof(DCTELEM)==2){ 75 if ( ((((uint64_t *)row)[0] & ~ROW0_MASK) | 76 ((uint64_t *)row)[1]) == 0) { 77 temp = (row[0] << 3) & 0xffff; 78 temp += temp << 16; 79 temp += temp << 32; 80 ((uint64_t *)row)[0] = temp; 81 ((uint64_t *)row)[1] = temp; 82 return; 83 } 84 }else{ 85 if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) { 86 row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3; 87 return; 88 } 89 } 90#else 91 if(sizeof(DCTELEM)==2){ 92 if (!(((uint32_t*)row)[1] | 93 ((uint32_t*)row)[2] | 94 ((uint32_t*)row)[3] | 95 row[1])) { 96 temp = (row[0] << 3) & 0xffff; 97 temp += temp << 16; 98 ((uint32_t*)row)[0]=((uint32_t*)row)[1] = 99 ((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp; 100 return; 101 } 102 }else{ 103 if (!(row[1]|row[2]|row[3]|row[4]|row[5]|row[6]|row[7])) { 104 row[0]=row[1]=row[2]=row[3]=row[4]=row[5]=row[6]=row[7]= row[0] << 3; 105 return; 106 } 107 } 108#endif 109 110 a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1)); 111 a1 = a0; 112 a2 = a0; 113 a3 = a0; 114 115 /* no need to optimize : gcc does it */ 116 a0 += W2 * row[2]; 117 a1 += W6 * row[2]; 118 a2 -= W6 * row[2]; 119 a3 -= W2 * row[2]; 120 121 b0 = MUL16(W1, row[1]); 122 MAC16(b0, W3, row[3]); 123 b1 = MUL16(W3, row[1]); 124 MAC16(b1, -W7, row[3]); 125 b2 = MUL16(W5, row[1]); 126 MAC16(b2, -W1, row[3]); 127 b3 = MUL16(W7, row[1]); 128 MAC16(b3, -W5, row[3]); 129 130#if HAVE_FAST_64BIT 131 temp = ((uint64_t*)row)[1]; 132#else 133 temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3]; 134#endif 135 if (temp != 0) { 136 a0 += W4*row[4] + W6*row[6]; 137 a1 += - W4*row[4] - W2*row[6]; 138 a2 += - W4*row[4] + W2*row[6]; 139 a3 += W4*row[4] - W6*row[6]; 140 141 MAC16(b0, W5, row[5]); 142 MAC16(b0, W7, row[7]); 143 144 MAC16(b1, -W1, row[5]); 145 MAC16(b1, -W5, row[7]); 146 147 MAC16(b2, W7, row[5]); 148 MAC16(b2, W3, row[7]); 149 150 MAC16(b3, W3, row[5]); 151 MAC16(b3, -W1, row[7]); 152 } 153 154 row[0] = (a0 + b0) >> ROW_SHIFT; 155 row[7] = (a0 - b0) >> ROW_SHIFT; 156 row[1] = (a1 + b1) >> ROW_SHIFT; 157 row[6] = (a1 - b1) >> ROW_SHIFT; 158 row[2] = (a2 + b2) >> ROW_SHIFT; 159 row[5] = (a2 - b2) >> ROW_SHIFT; 160 row[3] = (a3 + b3) >> ROW_SHIFT; 161 row[4] = (a3 - b3) >> ROW_SHIFT; 162} 163 164static inline void idctSparseColPut (uint8_t *dest, int line_size, 165 DCTELEM * col) 166{ 167 int a0, a1, a2, a3, b0, b1, b2, b3; 168 uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; 169 170 /* XXX: I did that only to give same values as previous code */ 171 a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); 172 a1 = a0; 173 a2 = a0; 174 a3 = a0; 175 176 a0 += + W2*col[8*2]; 177 a1 += + W6*col[8*2]; 178 a2 += - W6*col[8*2]; 179 a3 += - W2*col[8*2]; 180 181 b0 = MUL16(W1, col[8*1]); 182 b1 = MUL16(W3, col[8*1]); 183 b2 = MUL16(W5, col[8*1]); 184 b3 = MUL16(W7, col[8*1]); 185 186 MAC16(b0, + W3, col[8*3]); 187 MAC16(b1, - W7, col[8*3]); 188 MAC16(b2, - W1, col[8*3]); 189 MAC16(b3, - W5, col[8*3]); 190 191 if(col[8*4]){ 192 a0 += + W4*col[8*4]; 193 a1 += - W4*col[8*4]; 194 a2 += - W4*col[8*4]; 195 a3 += + W4*col[8*4]; 196 } 197 198 if (col[8*5]) { 199 MAC16(b0, + W5, col[8*5]); 200 MAC16(b1, - W1, col[8*5]); 201 MAC16(b2, + W7, col[8*5]); 202 MAC16(b3, + W3, col[8*5]); 203 } 204 205 if(col[8*6]){ 206 a0 += + W6*col[8*6]; 207 a1 += - W2*col[8*6]; 208 a2 += + W2*col[8*6]; 209 a3 += - W6*col[8*6]; 210 } 211 212 if (col[8*7]) { 213 MAC16(b0, + W7, col[8*7]); 214 MAC16(b1, - W5, col[8*7]); 215 MAC16(b2, + W3, col[8*7]); 216 MAC16(b3, - W1, col[8*7]); 217 } 218 219 dest[0] = cm[(a0 + b0) >> COL_SHIFT]; 220 dest += line_size; 221 dest[0] = cm[(a1 + b1) >> COL_SHIFT]; 222 dest += line_size; 223 dest[0] = cm[(a2 + b2) >> COL_SHIFT]; 224 dest += line_size; 225 dest[0] = cm[(a3 + b3) >> COL_SHIFT]; 226 dest += line_size; 227 dest[0] = cm[(a3 - b3) >> COL_SHIFT]; 228 dest += line_size; 229 dest[0] = cm[(a2 - b2) >> COL_SHIFT]; 230 dest += line_size; 231 dest[0] = cm[(a1 - b1) >> COL_SHIFT]; 232 dest += line_size; 233 dest[0] = cm[(a0 - b0) >> COL_SHIFT]; 234} 235 236static inline void idctSparseColAdd (uint8_t *dest, int line_size, 237 DCTELEM * col) 238{ 239 int a0, a1, a2, a3, b0, b1, b2, b3; 240 uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; 241 242 /* XXX: I did that only to give same values as previous code */ 243 a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); 244 a1 = a0; 245 a2 = a0; 246 a3 = a0; 247 248 a0 += + W2*col[8*2]; 249 a1 += + W6*col[8*2]; 250 a2 += - W6*col[8*2]; 251 a3 += - W2*col[8*2]; 252 253 b0 = MUL16(W1, col[8*1]); 254 b1 = MUL16(W3, col[8*1]); 255 b2 = MUL16(W5, col[8*1]); 256 b3 = MUL16(W7, col[8*1]); 257 258 MAC16(b0, + W3, col[8*3]); 259 MAC16(b1, - W7, col[8*3]); 260 MAC16(b2, - W1, col[8*3]); 261 MAC16(b3, - W5, col[8*3]); 262 263 if(col[8*4]){ 264 a0 += + W4*col[8*4]; 265 a1 += - W4*col[8*4]; 266 a2 += - W4*col[8*4]; 267 a3 += + W4*col[8*4]; 268 } 269 270 if (col[8*5]) { 271 MAC16(b0, + W5, col[8*5]); 272 MAC16(b1, - W1, col[8*5]); 273 MAC16(b2, + W7, col[8*5]); 274 MAC16(b3, + W3, col[8*5]); 275 } 276 277 if(col[8*6]){ 278 a0 += + W6*col[8*6]; 279 a1 += - W2*col[8*6]; 280 a2 += + W2*col[8*6]; 281 a3 += - W6*col[8*6]; 282 } 283 284 if (col[8*7]) { 285 MAC16(b0, + W7, col[8*7]); 286 MAC16(b1, - W5, col[8*7]); 287 MAC16(b2, + W3, col[8*7]); 288 MAC16(b3, - W1, col[8*7]); 289 } 290 291 dest[0] = cm[dest[0] + ((a0 + b0) >> COL_SHIFT)]; 292 dest += line_size; 293 dest[0] = cm[dest[0] + ((a1 + b1) >> COL_SHIFT)]; 294 dest += line_size; 295 dest[0] = cm[dest[0] + ((a2 + b2) >> COL_SHIFT)]; 296 dest += line_size; 297 dest[0] = cm[dest[0] + ((a3 + b3) >> COL_SHIFT)]; 298 dest += line_size; 299 dest[0] = cm[dest[0] + ((a3 - b3) >> COL_SHIFT)]; 300 dest += line_size; 301 dest[0] = cm[dest[0] + ((a2 - b2) >> COL_SHIFT)]; 302 dest += line_size; 303 dest[0] = cm[dest[0] + ((a1 - b1) >> COL_SHIFT)]; 304 dest += line_size; 305 dest[0] = cm[dest[0] + ((a0 - b0) >> COL_SHIFT)]; 306} 307 308static inline void idctSparseCol (DCTELEM * col) 309{ 310 int a0, a1, a2, a3, b0, b1, b2, b3; 311 312 /* XXX: I did that only to give same values as previous code */ 313 a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); 314 a1 = a0; 315 a2 = a0; 316 a3 = a0; 317 318 a0 += + W2*col[8*2]; 319 a1 += + W6*col[8*2]; 320 a2 += - W6*col[8*2]; 321 a3 += - W2*col[8*2]; 322 323 b0 = MUL16(W1, col[8*1]); 324 b1 = MUL16(W3, col[8*1]); 325 b2 = MUL16(W5, col[8*1]); 326 b3 = MUL16(W7, col[8*1]); 327 328 MAC16(b0, + W3, col[8*3]); 329 MAC16(b1, - W7, col[8*3]); 330 MAC16(b2, - W1, col[8*3]); 331 MAC16(b3, - W5, col[8*3]); 332 333 if(col[8*4]){ 334 a0 += + W4*col[8*4]; 335 a1 += - W4*col[8*4]; 336 a2 += - W4*col[8*4]; 337 a3 += + W4*col[8*4]; 338 } 339 340 if (col[8*5]) { 341 MAC16(b0, + W5, col[8*5]); 342 MAC16(b1, - W1, col[8*5]); 343 MAC16(b2, + W7, col[8*5]); 344 MAC16(b3, + W3, col[8*5]); 345 } 346 347 if(col[8*6]){ 348 a0 += + W6*col[8*6]; 349 a1 += - W2*col[8*6]; 350 a2 += + W2*col[8*6]; 351 a3 += - W6*col[8*6]; 352 } 353 354 if (col[8*7]) { 355 MAC16(b0, + W7, col[8*7]); 356 MAC16(b1, - W5, col[8*7]); 357 MAC16(b2, + W3, col[8*7]); 358 MAC16(b3, - W1, col[8*7]); 359 } 360 361 col[0 ] = ((a0 + b0) >> COL_SHIFT); 362 col[8 ] = ((a1 + b1) >> COL_SHIFT); 363 col[16] = ((a2 + b2) >> COL_SHIFT); 364 col[24] = ((a3 + b3) >> COL_SHIFT); 365 col[32] = ((a3 - b3) >> COL_SHIFT); 366 col[40] = ((a2 - b2) >> COL_SHIFT); 367 col[48] = ((a1 - b1) >> COL_SHIFT); 368 col[56] = ((a0 - b0) >> COL_SHIFT); 369} 370 371void ff_simple_idct_put(uint8_t *dest, int line_size, DCTELEM *block) 372{ 373 int i; 374 for(i=0; i<8; i++) 375 idctRowCondDC(block + i*8); 376 377 for(i=0; i<8; i++) 378 idctSparseColPut(dest + i, line_size, block + i); 379} 380 381void ff_simple_idct_add(uint8_t *dest, int line_size, DCTELEM *block) 382{ 383 int i; 384 for(i=0; i<8; i++) 385 idctRowCondDC(block + i*8); 386 387 for(i=0; i<8; i++) 388 idctSparseColAdd(dest + i, line_size, block + i); 389} 390 391void ff_simple_idct(DCTELEM *block) 392{ 393 int i; 394 for(i=0; i<8; i++) 395 idctRowCondDC(block + i*8); 396 397 for(i=0; i<8; i++) 398 idctSparseCol(block + i); 399} 400 401/* 2x4x8 idct */ 402 403#define CN_SHIFT 12 404#define C_FIX(x) ((int)((x) * (1 << CN_SHIFT) + 0.5)) 405#define C1 C_FIX(0.6532814824) 406#define C2 C_FIX(0.2705980501) 407 408/* row idct is multiple by 16 * sqrt(2.0), col idct4 is normalized, 409 and the butterfly must be multiplied by 0.5 * sqrt(2.0) */ 410#define C_SHIFT (4+1+12) 411 412static inline void idct4col_put(uint8_t *dest, int line_size, const DCTELEM *col) 413{ 414 int c0, c1, c2, c3, a0, a1, a2, a3; 415 const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; 416 417 a0 = col[8*0]; 418 a1 = col[8*2]; 419 a2 = col[8*4]; 420 a3 = col[8*6]; 421 c0 = ((a0 + a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1)); 422 c2 = ((a0 - a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1)); 423 c1 = a1 * C1 + a3 * C2; 424 c3 = a1 * C2 - a3 * C1; 425 dest[0] = cm[(c0 + c1) >> C_SHIFT]; 426 dest += line_size; 427 dest[0] = cm[(c2 + c3) >> C_SHIFT]; 428 dest += line_size; 429 dest[0] = cm[(c2 - c3) >> C_SHIFT]; 430 dest += line_size; 431 dest[0] = cm[(c0 - c1) >> C_SHIFT]; 432} 433 434#define BF(k) \ 435{\ 436 int a0, a1;\ 437 a0 = ptr[k];\ 438 a1 = ptr[8 + k];\ 439 ptr[k] = a0 + a1;\ 440 ptr[8 + k] = a0 - a1;\ 441} 442 443/* only used by DV codec. The input must be interlaced. 128 is added 444 to the pixels before clamping to avoid systematic error 445 (1024*sqrt(2)) offset would be needed otherwise. */ 446/* XXX: I think a 1.0/sqrt(2) normalization should be needed to 447 compensate the extra butterfly stage - I don't have the full DV 448 specification */ 449void ff_simple_idct248_put(uint8_t *dest, int line_size, DCTELEM *block) 450{ 451 int i; 452 DCTELEM *ptr; 453 454 /* butterfly */ 455 ptr = block; 456 for(i=0;i<4;i++) { 457 BF(0); 458 BF(1); 459 BF(2); 460 BF(3); 461 BF(4); 462 BF(5); 463 BF(6); 464 BF(7); 465 ptr += 2 * 8; 466 } 467 468 /* IDCT8 on each line */ 469 for(i=0; i<8; i++) { 470 idctRowCondDC(block + i*8); 471 } 472 473 /* IDCT4 and store */ 474 for(i=0;i<8;i++) { 475 idct4col_put(dest + i, 2 * line_size, block + i); 476 idct4col_put(dest + line_size + i, 2 * line_size, block + 8 + i); 477 } 478} 479 480/* 8x4 & 4x8 WMV2 IDCT */ 481#undef CN_SHIFT 482#undef C_SHIFT 483#undef C_FIX 484#undef C1 485#undef C2 486#define CN_SHIFT 12 487#define C_FIX(x) ((int)((x) * 1.414213562 * (1 << CN_SHIFT) + 0.5)) 488#define C1 C_FIX(0.6532814824) 489#define C2 C_FIX(0.2705980501) 490#define C3 C_FIX(0.5) 491#define C_SHIFT (4+1+12) 492static inline void idct4col_add(uint8_t *dest, int line_size, const DCTELEM *col) 493{ 494 int c0, c1, c2, c3, a0, a1, a2, a3; 495 const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; 496 497 a0 = col[8*0]; 498 a1 = col[8*1]; 499 a2 = col[8*2]; 500 a3 = col[8*3]; 501 c0 = (a0 + a2)*C3 + (1 << (C_SHIFT - 1)); 502 c2 = (a0 - a2)*C3 + (1 << (C_SHIFT - 1)); 503 c1 = a1 * C1 + a3 * C2; 504 c3 = a1 * C2 - a3 * C1; 505 dest[0] = cm[dest[0] + ((c0 + c1) >> C_SHIFT)]; 506 dest += line_size; 507 dest[0] = cm[dest[0] + ((c2 + c3) >> C_SHIFT)]; 508 dest += line_size; 509 dest[0] = cm[dest[0] + ((c2 - c3) >> C_SHIFT)]; 510 dest += line_size; 511 dest[0] = cm[dest[0] + ((c0 - c1) >> C_SHIFT)]; 512} 513 514#define RN_SHIFT 15 515#define R_FIX(x) ((int)((x) * 1.414213562 * (1 << RN_SHIFT) + 0.5)) 516#define R1 R_FIX(0.6532814824) 517#define R2 R_FIX(0.2705980501) 518#define R3 R_FIX(0.5) 519#define R_SHIFT 11 520static inline void idct4row(DCTELEM *row) 521{ 522 int c0, c1, c2, c3, a0, a1, a2, a3; 523 //const uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; 524 525 a0 = row[0]; 526 a1 = row[1]; 527 a2 = row[2]; 528 a3 = row[3]; 529 c0 = (a0 + a2)*R3 + (1 << (R_SHIFT - 1)); 530 c2 = (a0 - a2)*R3 + (1 << (R_SHIFT - 1)); 531 c1 = a1 * R1 + a3 * R2; 532 c3 = a1 * R2 - a3 * R1; 533 row[0]= (c0 + c1) >> R_SHIFT; 534 row[1]= (c2 + c3) >> R_SHIFT; 535 row[2]= (c2 - c3) >> R_SHIFT; 536 row[3]= (c0 - c1) >> R_SHIFT; 537} 538 539void ff_simple_idct84_add(uint8_t *dest, int line_size, DCTELEM *block) 540{ 541 int i; 542 543 /* IDCT8 on each line */ 544 for(i=0; i<4; i++) { 545 idctRowCondDC(block + i*8); 546 } 547 548 /* IDCT4 and store */ 549 for(i=0;i<8;i++) { 550 idct4col_add(dest + i, line_size, block + i); 551 } 552} 553 554void ff_simple_idct48_add(uint8_t *dest, int line_size, DCTELEM *block) 555{ 556 int i; 557 558 /* IDCT4 on each line */ 559 for(i=0; i<8; i++) { 560 idct4row(block + i*8); 561 } 562 563 /* IDCT8 and store */ 564 for(i=0; i<4; i++){ 565 idctSparseColAdd(dest + i, line_size, block + i); 566 } 567} 568 569void ff_simple_idct44_add(uint8_t *dest, int line_size, DCTELEM *block) 570{ 571 int i; 572 573 /* IDCT4 on each line */ 574 for(i=0; i<4; i++) { 575 idct4row(block + i*8); 576 } 577 578 /* IDCT4 and store */ 579 for(i=0; i<4; i++){ 580 idct4col_add(dest + i, line_size, block + i); 581 } 582} 583