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   1 /*
   2  * MPEG-1/2 decoder
   3  * Copyright (c) 2000, 2001 Fabrice Bellard
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav 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  * Libav 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 Libav; 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
  25  * MPEG-1/2 decoder
  26  */
  27
  28 #include <inttypes.h>
  29
  30 #include "libavutil/attributes.h"
  31 #include "libavutil/internal.h"
  32 #include "libavutil/stereo3d.h"
  33
  34 #include "avcodec.h"
  35 #include "bytestream.h"
  36 #include "error_resilience.h"
  37 #include "idctdsp.h"
  38 #include "internal.h"
  39 #include "mpeg_er.h"
  40 #include "mpeg12.h"
  41 #include "mpeg12data.h"
  42 #include "mpegutils.h"
  43 #include "mpegvideo.h"
  44 #include "mpegvideodata.h"
  45 #include "profiles.h"
  46 #include "thread.h"
  47 #include "version.h"
  48 #include "xvmc_internal.h"
  49
  50 typedef struct Mpeg1Context {
  51     MpegEncContext mpeg_enc_ctx;
  52     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  53     int repeat_field;           /* true if we must repeat the field */
  54     AVPanScan pan_scan;         /* some temporary storage for the panscan */
  55     AVStereo3D stereo3d;
  56     int has_stereo3d;
  57     uint8_t *a53_caption;
  58     int a53_caption_size;
  59     uint8_t afd;
  60     int has_afd;
  61     int slice_count;
  62     int save_aspect_info;
  63     int save_width, save_height, save_progressive_seq;
  64     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
  65     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
  66     int closed_gop;             /* GOP is closed */
  67     int first_slice;
  68     int extradata_decoded;
  69 } Mpeg1Context;
  70
  71 #define MB_TYPE_ZERO_MV   0x20000000
  72
  73 static const uint32_t ptype2mb_type[7] = {
  74                     MB_TYPE_INTRA,
  75                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  76                     MB_TYPE_L0,
  77                     MB_TYPE_L0 | MB_TYPE_CBP,
  78     MB_TYPE_QUANT | MB_TYPE_INTRA,
  79     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  80     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
  81 };
  82
  83 static const uint32_t btype2mb_type[11] = {
  84                     MB_TYPE_INTRA,
  85                     MB_TYPE_L1,
  86                     MB_TYPE_L1   | MB_TYPE_CBP,
  87                     MB_TYPE_L0,
  88                     MB_TYPE_L0   | MB_TYPE_CBP,
  89                     MB_TYPE_L0L1,
  90                     MB_TYPE_L0L1 | MB_TYPE_CBP,
  91     MB_TYPE_QUANT | MB_TYPE_INTRA,
  92     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
  93     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
  94     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
  95 };
  96
  97 static const uint8_t non_linear_qscale[32] = {
  98      0,  1,  2,  3,  4,  5,   6,   7,
  99      8, 10, 12, 14, 16, 18,  20,  22,
 100     24, 28, 32, 36, 40, 44,  48,  52,
 101     56, 64, 72, 80, 88, 96, 104, 112,
 102 };
 103
 104 /* as H.263, but only 17 codes */
 105 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 106 {
 107     int code, sign, val, shift;
 108
 109     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
 110     if (code == 0)
 111         return pred;
 112     if (code < 0)
 113         return 0xffff;
 114
 115     sign  = get_bits1(&s->gb);
 116     shift = fcode - 1;
 117     val   = code;
 118     if (shift) {
 119         val  = (val - 1) << shift;
 120         val |= get_bits(&s->gb, shift);
 121         val++;
 122     }
 123     if (sign)
 124         val = -val;
 125     val += pred;
 126
 127     /* modulo decoding */
 128     return sign_extend(val, 5 + shift);
 129 }
 130
 131 #define MAX_INDEX (64 - 1)
 132 #define check_scantable_index(ctx, x)                                         \
 133     do {                                                                      \
 134         if ((x) > MAX_INDEX) {                                                \
 135             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
 136                    ctx->mb_x, ctx->mb_y);                                     \
 137             return AVERROR_INVALIDDATA;                                       \
 138         }                                                                     \
 139     } while (0)
 140
 141 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 142                                            int16_t *block, int n)
 143 {
 144     int level, i, j, run;
 145     RLTable *rl                  = &ff_rl_mpeg1;
 146     uint8_t *const scantable     = s->intra_scantable.permutated;
 147     const uint16_t *quant_matrix = s->inter_matrix;
 148     const int qscale             = s->qscale;
 149
 150     {
 151         OPEN_READER(re, &s->gb);
 152         i = -1;
 153         // special case for first coefficient, no need to add second VLC table
 154         UPDATE_CACHE(re, &s->gb);
 155         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 156             level = (3 * qscale * quant_matrix[0]) >> 5;
 157             level = (level - 1) | 1;
 158             if (GET_CACHE(re, &s->gb) & 0x40000000)
 159                 level = -level;
 160             block[0] = level;
 161             i++;
 162             SKIP_BITS(re, &s->gb, 2);
 163             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 164                 goto end;
 165         }
 166         /* now quantify & encode AC coefficients */
 167         for (;;) {
 168             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 169                        TEX_VLC_BITS, 2, 0);
 170
 171             if (level != 0) {
 172                 i += run;
 173                 if (i > MAX_INDEX)
 174                     break;
 175                 j = scantable[i];
 176                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 177                 level = (level - 1) | 1;
 178                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 179                         SHOW_SBITS(re, &s->gb, 1);
 180                 SKIP_BITS(re, &s->gb, 1);
 181             } else {
 182                 /* escape */
 183                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 184                 LAST_SKIP_BITS(re, &s->gb, 6);
 185                 UPDATE_CACHE(re, &s->gb);
 186                 level = SHOW_SBITS(re, &s->gb, 8);
 187                 SKIP_BITS(re, &s->gb, 8);
 188                 if (level == -128) {
 189                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 190                     SKIP_BITS(re, &s->gb, 8);
 191                 } else if (level == 0) {
 192                     level = SHOW_UBITS(re, &s->gb, 8);
 193                     SKIP_BITS(re, &s->gb, 8);
 194                 }
 195                 i += run;
 196                 if (i > MAX_INDEX)
 197                     break;
 198                 j = scantable[i];
 199                 if (level < 0) {
 200                     level = -level;
 201                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 202                     level = (level - 1) | 1;
 203                     level = -level;
 204                 } else {
 205                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 206                     level = (level - 1) | 1;
 207                 }
 208             }
 209
 210             block[j] = level;
 211             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 212                 break;
 213             UPDATE_CACHE(re, &s->gb);
 214         }
 215 end:
 216         LAST_SKIP_BITS(re, &s->gb, 2);
 217         CLOSE_READER(re, &s->gb);
 218     }
 219
 220     check_scantable_index(s, i);
 221
 222     s->block_last_index[n] = i;
 223     return 0;
 224 }
 225
 226 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
 227                                                 int16_t *block, int n)
 228 {
 229     int level, i, j, run;
 230     RLTable *rl              = &ff_rl_mpeg1;
 231     uint8_t *const scantable = s->intra_scantable.permutated;
 232     const int qscale         = s->qscale;
 233
 234     {
 235         OPEN_READER(re, &s->gb);
 236         i = -1;
 237         // Special case for first coefficient, no need to add second VLC table.
 238         UPDATE_CACHE(re, &s->gb);
 239         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 240             level = (3 * qscale) >> 1;
 241             level = (level - 1) | 1;
 242             if (GET_CACHE(re, &s->gb) & 0x40000000)
 243                 level = -level;
 244             block[0] = level;
 245             i++;
 246             SKIP_BITS(re, &s->gb, 2);
 247             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 248                 goto end;
 249         }
 250
 251         /* now quantify & encode AC coefficients */
 252         for (;;) {
 253             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 254                        TEX_VLC_BITS, 2, 0);
 255
 256             if (level != 0) {
 257                 i += run;
 258                 if (i > MAX_INDEX)
 259                     break;
 260                 j = scantable[i];
 261                 level = ((level * 2 + 1) * qscale) >> 1;
 262                 level = (level - 1) | 1;
 263                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 264                         SHOW_SBITS(re, &s->gb, 1);
 265                 SKIP_BITS(re, &s->gb, 1);
 266             } else {
 267                 /* escape */
 268                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 269                 LAST_SKIP_BITS(re, &s->gb, 6);
 270                 UPDATE_CACHE(re, &s->gb);
 271                 level = SHOW_SBITS(re, &s->gb, 8);
 272                 SKIP_BITS(re, &s->gb, 8);
 273                 if (level == -128) {
 274                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 275                     SKIP_BITS(re, &s->gb, 8);
 276                 } else if (level == 0) {
 277                     level = SHOW_UBITS(re, &s->gb, 8);
 278                     SKIP_BITS(re, &s->gb, 8);
 279                 }
 280                 i += run;
 281                 if (i > MAX_INDEX)
 282                     break;
 283                 j = scantable[i];
 284                 if (level < 0) {
 285                     level = -level;
 286                     level = ((level * 2 + 1) * qscale) >> 1;
 287                     level = (level - 1) | 1;
 288                     level = -level;
 289                 } else {
 290                     level = ((level * 2 + 1) * qscale) >> 1;
 291                     level = (level - 1) | 1;
 292                 }
 293             }
 294
 295             block[j] = level;
 296             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 297                 break;
 298             UPDATE_CACHE(re, &s->gb);
 299         }
 300 end:
 301         LAST_SKIP_BITS(re, &s->gb, 2);
 302         CLOSE_READER(re, &s->gb);
 303     }
 304
 305     check_scantable_index(s, i);
 306
 307     s->block_last_index[n] = i;
 308     return 0;
 309 }
 310
 311 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 312                                                int16_t *block, int n)
 313 {
 314     int level, i, j, run;
 315     RLTable *rl = &ff_rl_mpeg1;
 316     uint8_t *const scantable = s->intra_scantable.permutated;
 317     const uint16_t *quant_matrix;
 318     const int qscale = s->qscale;
 319     int mismatch;
 320
 321     mismatch = 1;
 322
 323     {
 324         OPEN_READER(re, &s->gb);
 325         i = -1;
 326         if (n < 4)
 327             quant_matrix = s->inter_matrix;
 328         else
 329             quant_matrix = s->chroma_inter_matrix;
 330
 331         // Special case for first coefficient, no need to add second VLC table.
 332         UPDATE_CACHE(re, &s->gb);
 333         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 334             level = (3 * qscale * quant_matrix[0]) >> 5;
 335             if (GET_CACHE(re, &s->gb) & 0x40000000)
 336                 level = -level;
 337             block[0]  = level;
 338             mismatch ^= level;
 339             i++;
 340             SKIP_BITS(re, &s->gb, 2);
 341             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 342                 goto end;
 343         }
 344
 345         /* now quantify & encode AC coefficients */
 346         for (;;) {
 347             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 348                        TEX_VLC_BITS, 2, 0);
 349
 350             if (level != 0) {
 351                 i += run;
 352                 if (i > MAX_INDEX)
 353                     break;
 354                 j = scantable[i];
 355                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 356                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 357                         SHOW_SBITS(re, &s->gb, 1);
 358                 SKIP_BITS(re, &s->gb, 1);
 359             } else {
 360                 /* escape */
 361                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 362                 LAST_SKIP_BITS(re, &s->gb, 6);
 363                 UPDATE_CACHE(re, &s->gb);
 364                 level = SHOW_SBITS(re, &s->gb, 12);
 365                 SKIP_BITS(re, &s->gb, 12);
 366
 367                 i += run;
 368                 if (i > MAX_INDEX)
 369                     break;
 370                 j = scantable[i];
 371                 if (level < 0) {
 372                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 373                     level = -level;
 374                 } else {
 375                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 376                 }
 377             }
 378
 379             mismatch ^= level;
 380             block[j]  = level;
 381             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 382                 break;
 383             UPDATE_CACHE(re, &s->gb);
 384         }
 385 end:
 386         LAST_SKIP_BITS(re, &s->gb, 2);
 387         CLOSE_READER(re, &s->gb);
 388     }
 389     block[63] ^= (mismatch & 1);
 390
 391     check_scantable_index(s, i);
 392
 393     s->block_last_index[n] = i;
 394     return 0;
 395 }
 396
 397 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 398                                                     int16_t *block, int n)
 399 {
 400     int level, i, j, run;
 401     RLTable *rl              = &ff_rl_mpeg1;
 402     uint8_t *const scantable = s->intra_scantable.permutated;
 403     const int qscale         = s->qscale;
 404     OPEN_READER(re, &s->gb);
 405     i = -1;
 406
 407     // special case for first coefficient, no need to add second VLC table
 408     UPDATE_CACHE(re, &s->gb);
 409     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 410         level = (3 * qscale) >> 1;
 411         if (GET_CACHE(re, &s->gb) & 0x40000000)
 412             level = -level;
 413         block[0] = level;
 414         i++;
 415         SKIP_BITS(re, &s->gb, 2);
 416         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 417             goto end;
 418     }
 419
 420     /* now quantify & encode AC coefficients */
 421     for (;;) {
 422         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 423
 424         if (level != 0) {
 425             i += run;
 426             if (i > MAX_INDEX)
 427                 break;
 428             j = scantable[i];
 429             level = ((level * 2 + 1) * qscale) >> 1;
 430             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 431                     SHOW_SBITS(re, &s->gb, 1);
 432             SKIP_BITS(re, &s->gb, 1);
 433         } else {
 434             /* escape */
 435             run = SHOW_UBITS(re, &s->gb, 6) + 1;
 436             LAST_SKIP_BITS(re, &s->gb, 6);
 437             UPDATE_CACHE(re, &s->gb);
 438             level = SHOW_SBITS(re, &s->gb, 12);
 439             SKIP_BITS(re, &s->gb, 12);
 440
 441             i += run;
 442             if (i > MAX_INDEX)
 443                 break;
 444             j = scantable[i];
 445             if (level < 0) {
 446                 level = ((-level * 2 + 1) * qscale) >> 1;
 447                 level = -level;
 448             } else {
 449                 level = ((level * 2 + 1) * qscale) >> 1;
 450             }
 451         }
 452
 453         block[j] = level;
 454         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 455             break;
 456         UPDATE_CACHE(re, &s->gb);
 457     }
 458 end:
 459     LAST_SKIP_BITS(re, &s->gb, 2);
 460     CLOSE_READER(re, &s->gb);
 461
 462     check_scantable_index(s, i);
 463
 464     s->block_last_index[n] = i;
 465     return 0;
 466 }
 467
 468 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
 469                                            int16_t *block, int n)
 470 {
 471     int level, dc, diff, i, j, run;
 472     int component;
 473     RLTable *rl;
 474     uint8_t *const scantable = s->intra_scantable.permutated;
 475     const uint16_t *quant_matrix;
 476     const int qscale = s->qscale;
 477     int mismatch;
 478
 479     /* DC coefficient */
 480     if (n < 4) {
 481         quant_matrix = s->intra_matrix;
 482         component    = 0;
 483     } else {
 484         quant_matrix = s->chroma_intra_matrix;
 485         component    = (n & 1) + 1;
 486     }
 487     diff = decode_dc(&s->gb, component);
 488     if (diff >= 0xffff)
 489         return AVERROR_INVALIDDATA;
 490     dc  = s->last_dc[component];
 491     dc += diff;
 492     s->last_dc[component] = dc;
 493     block[0] = dc << (3 - s->intra_dc_precision);
 494     ff_dlog(s->avctx, "dc=%d\n", block[0]);
 495     mismatch = block[0] ^ 1;
 496     i = 0;
 497     if (s->intra_vlc_format)
 498         rl = &ff_rl_mpeg2;
 499     else
 500         rl = &ff_rl_mpeg1;
 501
 502     {
 503         OPEN_READER(re, &s->gb);
 504         /* now quantify & encode AC coefficients */
 505         for (;;) {
 506             UPDATE_CACHE(re, &s->gb);
 507             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 508                        TEX_VLC_BITS, 2, 0);
 509
 510             if (level == 127) {
 511                 break;
 512             } else if (level != 0) {
 513                 i += run;
 514                 if (i > MAX_INDEX)
 515                     break;
 516                 j = scantable[i];
 517                 level = (level * qscale * quant_matrix[j]) >> 4;
 518                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 519                         SHOW_SBITS(re, &s->gb, 1);
 520                 LAST_SKIP_BITS(re, &s->gb, 1);
 521             } else {
 522                 /* escape */
 523                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 524                 LAST_SKIP_BITS(re, &s->gb, 6);
 525                 UPDATE_CACHE(re, &s->gb);
 526                 level = SHOW_SBITS(re, &s->gb, 12);
 527                 SKIP_BITS(re, &s->gb, 12);
 528                 i += run;
 529                 if (i > MAX_INDEX)
 530                     break;
 531                 j = scantable[i];
 532                 if (level < 0) {
 533                     level = (-level * qscale * quant_matrix[j]) >> 4;
 534                     level = -level;
 535                 } else {
 536                     level = (level * qscale * quant_matrix[j]) >> 4;
 537                 }
 538             }
 539
 540             mismatch ^= level;
 541             block[j]  = level;
 542         }
 543         CLOSE_READER(re, &s->gb);
 544     }
 545     block[63] ^= mismatch & 1;
 546
 547     check_scantable_index(s, i);
 548
 549     s->block_last_index[n] = i;
 550     return 0;
 551 }
 552
 553 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
 554                                                 int16_t *block, int n)
 555 {
 556     int level, dc, diff, i, j, run;
 557     int component;
 558     RLTable *rl;
 559     uint8_t *const scantable = s->intra_scantable.permutated;
 560     const uint16_t *quant_matrix;
 561     const int qscale = s->qscale;
 562
 563     /* DC coefficient */
 564     if (n < 4) {
 565         quant_matrix = s->intra_matrix;
 566         component    = 0;
 567     } else {
 568         quant_matrix = s->chroma_intra_matrix;
 569         component    = (n & 1) + 1;
 570     }
 571     diff = decode_dc(&s->gb, component);
 572     if (diff >= 0xffff)
 573         return AVERROR_INVALIDDATA;
 574     dc = s->last_dc[component];
 575     dc += diff;
 576     s->last_dc[component] = dc;
 577     block[0] = dc << (3 - s->intra_dc_precision);
 578     i = 0;
 579     if (s->intra_vlc_format)
 580         rl = &ff_rl_mpeg2;
 581     else
 582         rl = &ff_rl_mpeg1;
 583
 584     {
 585         OPEN_READER(re, &s->gb);
 586         /* now quantify & encode AC coefficients */
 587         for (;;) {
 588             UPDATE_CACHE(re, &s->gb);
 589             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 590                        TEX_VLC_BITS, 2, 0);
 591
 592             if (level == 127) {
 593                 break;
 594             } else if (level != 0) {
 595                 i += run;
 596                 if (i > MAX_INDEX)
 597                     break;
 598                 j = scantable[i];
 599                 level = (level * qscale * quant_matrix[j]) >> 4;
 600                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 601                         SHOW_SBITS(re, &s->gb, 1);
 602                 LAST_SKIP_BITS(re, &s->gb, 1);
 603             } else {
 604                 /* escape */
 605                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 606                 LAST_SKIP_BITS(re, &s->gb, 6);
 607                 UPDATE_CACHE(re, &s->gb);
 608                 level = SHOW_SBITS(re, &s->gb, 12);
 609                 SKIP_BITS(re, &s->gb, 12);
 610                 i += run;
 611                 if (i > MAX_INDEX)
 612                     break;
 613                 j = scantable[i];
 614                 if (level < 0) {
 615                     level = (-level * qscale * quant_matrix[j]) >> 4;
 616                     level = -level;
 617                 } else {
 618                     level = (level * qscale * quant_matrix[j]) >> 4;
 619                 }
 620             }
 621
 622             block[j] = level;
 623         }
 624         CLOSE_READER(re, &s->gb);
 625     }
 626
 627     check_scantable_index(s, i);
 628
 629     s->block_last_index[n] = i;
 630     return 0;
 631 }
 632
 633 /******************************************/
 634 /* decoding */
 635
 636 static inline int get_dmv(MpegEncContext *s)
 637 {
 638     if (get_bits1(&s->gb))
 639         return 1 - (get_bits1(&s->gb) << 1);
 640     else
 641         return 0;
 642 }
 643
 644 static inline int get_qscale(MpegEncContext *s)
 645 {
 646     int qscale = get_bits(&s->gb, 5);
 647     if (s->q_scale_type)
 648         return non_linear_qscale[qscale];
 649     else
 650         return qscale << 1;
 651 }
 652
 653 /* motion type (for MPEG-2) */
 654 #define MT_FIELD 1
 655 #define MT_FRAME 2
 656 #define MT_16X8  2
 657 #define MT_DMV   3
 658
 659 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 660 {
 661     int i, j, k, cbp, val, mb_type, motion_type;
 662     const int mb_block_count = 4 + (1 << s->chroma_format);
 663     int ret;
 664
 665     ff_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 666
 667     assert(s->mb_skipped == 0);
 668
 669     if (s->mb_skip_run-- != 0) {
 670         if (s->pict_type == AV_PICTURE_TYPE_P) {
 671             s->mb_skipped = 1;
 672             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 673                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 674         } else {
 675             int mb_type;
 676
 677             if (s->mb_x)
 678                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 679             else
 680                 // FIXME not sure if this is allowed in MPEG at all
 681                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
 682             if (IS_INTRA(mb_type))
 683                 return AVERROR_INVALIDDATA;
 684             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 685                 mb_type | MB_TYPE_SKIP;
 686 //            assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
 687
 688             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 689                 s->mb_skipped = 1;
 690         }
 691
 692         return 0;
 693     }
 694
 695     switch (s->pict_type) {
 696     default:
 697     case AV_PICTURE_TYPE_I:
 698         if (get_bits1(&s->gb) == 0) {
 699             if (get_bits1(&s->gb) == 0) {
 700                 av_log(s->avctx, AV_LOG_ERROR,
 701                        "Invalid mb type in I-frame at %d %d\n",
 702                        s->mb_x, s->mb_y);
 703                 return AVERROR_INVALIDDATA;
 704             }
 705             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 706         } else {
 707             mb_type = MB_TYPE_INTRA;
 708         }
 709         break;
 710     case AV_PICTURE_TYPE_P:
 711         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 712         if (mb_type < 0) {
 713             av_log(s->avctx, AV_LOG_ERROR,
 714                    "Invalid mb type in P-frame at %d %d\n", s->mb_x, s->mb_y);
 715             return AVERROR_INVALIDDATA;
 716         }
 717         mb_type = ptype2mb_type[mb_type];
 718         break;
 719     case AV_PICTURE_TYPE_B:
 720         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 721         if (mb_type < 0) {
 722             av_log(s->avctx, AV_LOG_ERROR,
 723                    "Invalid mb type in B-frame at %d %d\n", s->mb_x, s->mb_y);
 724             return AVERROR_INVALIDDATA;
 725         }
 726         mb_type = btype2mb_type[mb_type];
 727         break;
 728     }
 729     ff_dlog(s->avctx, "mb_type=%x\n", mb_type);
 730 //    motion_type = 0; /* avoid warning */
 731     if (IS_INTRA(mb_type)) {
 732         s->bdsp.clear_blocks(s->block[0]);
 733
 734         if (!s->chroma_y_shift)
 735             s->bdsp.clear_blocks(s->block[6]);
 736
 737         /* compute DCT type */
 738         // FIXME: add an interlaced_dct coded var?
 739         if (s->picture_structure == PICT_FRAME &&
 740             !s->frame_pred_frame_dct)
 741             s->interlaced_dct = get_bits1(&s->gb);
 742
 743         if (IS_QUANT(mb_type))
 744             s->qscale = get_qscale(s);
 745
 746         if (s->concealment_motion_vectors) {
 747             /* just parse them */
 748             if (s->picture_structure != PICT_FRAME)
 749                 skip_bits1(&s->gb);  /* field select */
 750
 751             s->mv[0][0][0]      =
 752             s->last_mv[0][0][0] =
 753             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
 754                                                      s->last_mv[0][0][0]);
 755             s->mv[0][0][1]      =
 756             s->last_mv[0][0][1] =
 757             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
 758                                                      s->last_mv[0][0][1]);
 759
 760             skip_bits1(&s->gb); /* marker */
 761         } else {
 762             /* reset mv prediction */
 763             memset(s->last_mv, 0, sizeof(s->last_mv));
 764         }
 765         s->mb_intra = 1;
 766 #if FF_API_XVMC
 767 FF_DISABLE_DEPRECATION_WARNINGS
 768         // if 1, we memcpy blocks in xvmcvideo
 769         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
 770             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 771 FF_ENABLE_DEPRECATION_WARNINGS
 772 #endif /* FF_API_XVMC */
 773
 774         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 775             if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
 776                 for (i = 0; i < 6; i++)
 777                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 778             } else {
 779                 for (i = 0; i < mb_block_count; i++)
 780                     if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 781                         return ret;
 782             }
 783         } else {
 784             for (i = 0; i < 6; i++) {
 785                 ret = ff_mpeg1_decode_block_intra(&s->gb,
 786                                                   s->intra_matrix,
 787                                                   s->intra_scantable.permutated,
 788                                                   s->last_dc, *s->pblocks[i],
 789                                                   i, s->qscale);
 790                 if (ret < 0) {
 791                     av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",
 792                            s->mb_x, s->mb_y);
 793                     return ret;
 794                 }
 795
 796                 s->block_last_index[i] = ret;
 797             }
 798         }
 799     } else {
 800         if (mb_type & MB_TYPE_ZERO_MV) {
 801             assert(mb_type & MB_TYPE_CBP);
 802
 803             s->mv_dir = MV_DIR_FORWARD;
 804             if (s->picture_structure == PICT_FRAME) {
 805                 if (!s->frame_pred_frame_dct)
 806                     s->interlaced_dct = get_bits1(&s->gb);
 807                 s->mv_type = MV_TYPE_16X16;
 808             } else {
 809                 s->mv_type            = MV_TYPE_FIELD;
 810                 mb_type              |= MB_TYPE_INTERLACED;
 811                 s->field_select[0][0] = s->picture_structure - 1;
 812             }
 813
 814             if (IS_QUANT(mb_type))
 815                 s->qscale = get_qscale(s);
 816
 817             s->last_mv[0][0][0] = 0;
 818             s->last_mv[0][0][1] = 0;
 819             s->last_mv[0][1][0] = 0;
 820             s->last_mv[0][1][1] = 0;
 821             s->mv[0][0][0]      = 0;
 822             s->mv[0][0][1]      = 0;
 823         } else {
 824             assert(mb_type & MB_TYPE_L0L1);
 825             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 826             /* get additional motion vector type */
 827             if (s->frame_pred_frame_dct) {
 828                 motion_type = MT_FRAME;
 829             } else {
 830                 motion_type = get_bits(&s->gb, 2);
 831                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 832                     s->interlaced_dct = get_bits1(&s->gb);
 833             }
 834
 835             if (IS_QUANT(mb_type))
 836                 s->qscale = get_qscale(s);
 837
 838             /* motion vectors */
 839             s->mv_dir = (mb_type >> 13) & 3;
 840             ff_dlog(s->avctx, "motion_type=%d\n", motion_type);
 841             switch (motion_type) {
 842             case MT_FRAME: /* or MT_16X8 */
 843                 if (s->picture_structure == PICT_FRAME) {
 844                     mb_type   |= MB_TYPE_16x16;
 845                     s->mv_type = MV_TYPE_16X16;
 846                     for (i = 0; i < 2; i++) {
 847                         if (USES_LIST(mb_type, i)) {
 848                             /* MT_FRAME */
 849                             s->mv[i][0][0]      =
 850                             s->last_mv[i][0][0] =
 851                             s->last_mv[i][1][0] =
 852                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 853                                                    s->last_mv[i][0][0]);
 854                             s->mv[i][0][1]      =
 855                             s->last_mv[i][0][1] =
 856                             s->last_mv[i][1][1] =
 857                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 858                                                    s->last_mv[i][0][1]);
 859                             /* full_pel: only for MPEG-1 */
 860                             if (s->full_pel[i]) {
 861                                 s->mv[i][0][0] <<= 1;
 862                                 s->mv[i][0][1] <<= 1;
 863                             }
 864                         }
 865                     }
 866                 } else {
 867                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 868                     s->mv_type = MV_TYPE_16X8;
 869                     for (i = 0; i < 2; i++) {
 870                         if (USES_LIST(mb_type, i)) {
 871                             /* MT_16X8 */
 872                             for (j = 0; j < 2; j++) {
 873                                 s->field_select[i][j] = get_bits1(&s->gb);
 874                                 for (k = 0; k < 2; k++) {
 875                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 876                                                              s->last_mv[i][j][k]);
 877                                     s->last_mv[i][j][k] = val;
 878                                     s->mv[i][j][k]      = val;
 879                                 }
 880                             }
 881                         }
 882                     }
 883                 }
 884                 break;
 885             case MT_FIELD:
 886                 s->mv_type = MV_TYPE_FIELD;
 887                 if (s->picture_structure == PICT_FRAME) {
 888                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 889                     for (i = 0; i < 2; i++) {
 890                         if (USES_LIST(mb_type, i)) {
 891                             for (j = 0; j < 2; j++) {
 892                                 s->field_select[i][j] = get_bits1(&s->gb);
 893                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 894                                                          s->last_mv[i][j][0]);
 895                                 s->last_mv[i][j][0] = val;
 896                                 s->mv[i][j][0]      = val;
 897                                 ff_dlog(s->avctx, "fmx=%d\n", val);
 898                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 899                                                          s->last_mv[i][j][1] >> 1);
 900                                 s->last_mv[i][j][1] = val << 1;
 901                                 s->mv[i][j][1]      = val;
 902                                 ff_dlog(s->avctx, "fmy=%d\n", val);
 903                             }
 904                         }
 905                     }
 906                 } else {
 907                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 908                     for (i = 0; i < 2; i++) {
 909                         if (USES_LIST(mb_type, i)) {
 910                             s->field_select[i][0] = get_bits1(&s->gb);
 911                             for (k = 0; k < 2; k++) {
 912                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 913                                                          s->last_mv[i][0][k]);
 914                                 s->last_mv[i][0][k] = val;
 915                                 s->last_mv[i][1][k] = val;
 916                                 s->mv[i][0][k]      = val;
 917                             }
 918                         }
 919                     }
 920                 }
 921                 break;
 922             case MT_DMV:
 923                 s->mv_type = MV_TYPE_DMV;
 924                 for (i = 0; i < 2; i++) {
 925                     if (USES_LIST(mb_type, i)) {
 926                         int dmx, dmy, mx, my, m;
 927                         const int my_shift = s->picture_structure == PICT_FRAME;
 928
 929                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 930                                                 s->last_mv[i][0][0]);
 931                         s->last_mv[i][0][0] = mx;
 932                         s->last_mv[i][1][0] = mx;
 933                         dmx = get_dmv(s);
 934                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 935                                                  s->last_mv[i][0][1] >> my_shift);
 936                         dmy = get_dmv(s);
 937
 938
 939                         s->last_mv[i][0][1] = my << my_shift;
 940                         s->last_mv[i][1][1] = my << my_shift;
 941
 942                         s->mv[i][0][0] = mx;
 943                         s->mv[i][0][1] = my;
 944                         s->mv[i][1][0] = mx; // not used
 945                         s->mv[i][1][1] = my; // not used
 946
 947                         if (s->picture_structure == PICT_FRAME) {
 948                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 949
 950                             // m = 1 + 2 * s->top_field_first;
 951                             m = s->top_field_first ? 1 : 3;
 952
 953                             /* top -> top pred */
 954                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 955                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 956                             m = 4 - m;
 957                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 958                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 959                         } else {
 960                             mb_type |= MB_TYPE_16x16;
 961
 962                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 963                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 964                             if (s->picture_structure == PICT_TOP_FIELD)
 965                                 s->mv[i][2][1]--;
 966                             else
 967                                 s->mv[i][2][1]++;
 968                         }
 969                     }
 970                 }
 971                 break;
 972             default:
 973                 av_log(s->avctx, AV_LOG_ERROR,
 974                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 975                 return AVERROR_INVALIDDATA;
 976             }
 977         }
 978
 979         s->mb_intra = 0;
 980         if (HAS_CBP(mb_type)) {
 981             s->bdsp.clear_blocks(s->block[0]);
 982
 983             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 984             if (mb_block_count > 6) {
 985                 cbp <<= mb_block_count - 6;
 986                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
 987                 s->bdsp.clear_blocks(s->block[6]);
 988             }
 989             if (cbp <= 0) {
 990                 av_log(s->avctx, AV_LOG_ERROR,
 991                        "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
 992                 return AVERROR_INVALIDDATA;
 993             }
 994
 995 #if FF_API_XVMC
 996 FF_DISABLE_DEPRECATION_WARNINGS
 997             // if 1, we memcpy blocks in xvmcvideo
 998             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
 999                 ff_xvmc_pack_pblocks(s, cbp);
1000 FF_ENABLE_DEPRECATION_WARNINGS
1001 #endif /* FF_API_XVMC */
1002
1003             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1004                 if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1005                     for (i = 0; i < 6; i++) {
1006                         if (cbp & 32)
1007                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1008                         else
1009                             s->block_last_index[i] = -1;
1010                         cbp += cbp;
1011                     }
1012                 } else {
1013                     cbp <<= 12 - mb_block_count;
1014
1015                     for (i = 0; i < mb_block_count; i++) {
1016                         if (cbp & (1 << 11)) {
1017                             if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
1018                                 return ret;
1019                         } else {
1020                             s->block_last_index[i] = -1;
1021                         }
1022                         cbp += cbp;
1023                     }
1024                 }
1025             } else {
1026                 if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1027                     for (i = 0; i < 6; i++) {
1028                         if (cbp & 32)
1029                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1030                         else
1031                             s->block_last_index[i] = -1;
1032                         cbp += cbp;
1033                     }
1034                 } else {
1035                     for (i = 0; i < 6; i++) {
1036                         if (cbp & 32) {
1037                             if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
1038                                 return ret;
1039                         } else {
1040                             s->block_last_index[i] = -1;
1041                         }
1042                         cbp += cbp;
1043                     }
1044                 }
1045             }
1046         } else {
1047             for (i = 0; i < 12; i++)
1048                 s->block_last_index[i] = -1;
1049         }
1050     }
1051
1052     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1053
1054     return 0;
1055 }
1056
1057 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1058 {
1059     Mpeg1Context *s    = avctx->priv_data;
1060     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1061
1062     ff_mpv_decode_defaults(s2);
1063
1064     s->mpeg_enc_ctx.avctx  = avctx;
1065
1066     /* we need some permutation to store matrices,
1067      * until the decoder sets the real permutation. */
1068     ff_mpv_idct_init(s2);
1069     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1070     ff_mpeg12_init_vlcs();
1071
1072     s->mpeg_enc_ctx_allocated      = 0;
1073     s->mpeg_enc_ctx.picture_number = 0;
1074     s->repeat_field                = 0;
1075     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1076     avctx->color_range             = AVCOL_RANGE_MPEG;
1077     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1078         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1079     else
1080         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1081     return 0;
1082 }
1083
1084 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1085                                              const AVCodecContext *avctx_from)
1086 {
1087     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1088     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1089     int err;
1090
1091     if (avctx == avctx_from               ||
1092         !ctx_from->mpeg_enc_ctx_allocated ||
1093         !s1->context_initialized)
1094         return 0;
1095
1096     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1097     if (err)
1098         return err;
1099
1100     if (!ctx->mpeg_enc_ctx_allocated) {
1101         // copy the whole context after the initial MpegEncContext structure
1102         memcpy(ctx, ctx_from, sizeof(*ctx));
1103         memset(&ctx->mpeg_enc_ctx, 0, sizeof(ctx->mpeg_enc_ctx));
1104     }
1105
1106     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1107         s->picture_number++;
1108
1109     return 0;
1110 }
1111
1112 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1113                                  const uint8_t *new_perm)
1114 {
1115     uint16_t temp_matrix[64];
1116     int i;
1117
1118     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1119
1120     for (i = 0; i < 64; i++)
1121         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1122 }
1123
1124 #if FF_API_XVMC
1125 static const enum AVPixelFormat pixfmt_xvmc_mpg2_420[] = {
1126     AV_PIX_FMT_XVMC_MPEG2_IDCT,
1127     AV_PIX_FMT_XVMC_MPEG2_MC,
1128     AV_PIX_FMT_NONE
1129 };
1130 #endif /* FF_API_XVMC */
1131
1132 static const enum AVPixelFormat mpeg12_hwaccel_pixfmt_list_420[] = {
1133 #if CONFIG_MPEG2_DXVA2_HWACCEL
1134     AV_PIX_FMT_DXVA2_VLD,
1135 #endif
1136 #if CONFIG_MPEG2_D3D11VA_HWACCEL
1137     AV_PIX_FMT_D3D11VA_VLD,
1138 #endif
1139 #if CONFIG_MPEG2_VAAPI_HWACCEL
1140     AV_PIX_FMT_VAAPI,
1141 #endif
1142 #if CONFIG_MPEG1_VDPAU_HWACCEL | CONFIG_MPEG2_VDPAU_HWACCEL
1143     AV_PIX_FMT_VDPAU,
1144 #endif
1145     AV_PIX_FMT_YUV420P,
1146     AV_PIX_FMT_NONE
1147 };
1148
1149 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1150     AV_PIX_FMT_YUV422P,
1151     AV_PIX_FMT_NONE
1152 };
1153
1154 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1155     AV_PIX_FMT_YUV444P,
1156     AV_PIX_FMT_NONE
1157 };
1158
1159 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1160 {
1161     Mpeg1Context *s1  = avctx->priv_data;
1162     MpegEncContext *s = &s1->mpeg_enc_ctx;
1163     const enum AVPixelFormat *pix_fmts;
1164
1165 #if FF_API_XVMC
1166 FF_DISABLE_DEPRECATION_WARNINGS
1167     if (avctx->xvmc_acceleration)
1168         return ff_get_format(avctx, pixfmt_xvmc_mpg2_420);
1169 FF_ENABLE_DEPRECATION_WARNINGS
1170 #endif /* FF_API_XVMC */
1171
1172     if (s->chroma_format < 2)
1173         pix_fmts = mpeg12_hwaccel_pixfmt_list_420;
1174     else if (s->chroma_format == 2)
1175         pix_fmts = mpeg12_pixfmt_list_422;
1176     else
1177         pix_fmts = mpeg12_pixfmt_list_444;
1178
1179     return ff_get_format(avctx, pix_fmts);
1180 }
1181
1182 /* Call this function when we know all parameters.
1183  * It may be called in different places for MPEG-1 and MPEG-2. */
1184 static int mpeg_decode_postinit(AVCodecContext *avctx)
1185 {
1186     Mpeg1Context *s1  = avctx->priv_data;
1187     MpegEncContext *s = &s1->mpeg_enc_ctx;
1188     uint8_t old_permutation[64];
1189     int ret;
1190
1191     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1192         avctx->coded_width       != s->width                ||
1193         avctx->coded_height      != s->height               ||
1194         s1->save_width           != s->width                ||
1195         s1->save_height          != s->height               ||
1196         s1->save_aspect_info     != s->aspect_ratio_info    ||
1197         s1->save_progressive_seq != s->progressive_sequence ||
1198         0) {
1199         if (s1->mpeg_enc_ctx_allocated) {
1200             ParseContext pc = s->parse_context;
1201             s->parse_context.buffer = 0;
1202             ff_mpv_common_end(s);
1203             s->parse_context = pc;
1204         }
1205
1206         ret = ff_set_dimensions(avctx, s->width, s->height);
1207         if (ret < 0)
1208             return ret;
1209
1210         avctx->bit_rate          = s->bit_rate;
1211         s1->save_aspect_info     = s->aspect_ratio_info;
1212         s1->save_width           = s->width;
1213         s1->save_height          = s->height;
1214         s1->save_progressive_seq = s->progressive_sequence;
1215
1216         /* low_delay may be forced, in this case we will have B-frames
1217          * that behave like P-frames. */
1218         avctx->has_b_frames = !s->low_delay;
1219
1220         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1221             // MPEG-1 fps
1222             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1223             // MPEG-1 aspect
1224             avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1225             avctx->ticks_per_frame     = 1;
1226         } else { // MPEG-2
1227             // MPEG-2 fps
1228             av_reduce(&s->avctx->framerate.num,
1229                       &s->avctx->framerate.den,
1230                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num * 2,
1231                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1232                       1 << 30);
1233             avctx->ticks_per_frame = 2;
1234             // MPEG-2 aspect
1235             if (s->aspect_ratio_info > 1) {
1236                 AVRational dar =
1237                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1238                                       (AVRational) { s1->pan_scan.width,
1239                                                      s1->pan_scan.height }),
1240                              (AVRational) { s->width, s->height });
1241
1242                 /* We ignore the spec here and guess a bit as reality does not
1243                  * match the spec, see for example res_change_ffmpeg_aspect.ts
1244                  * and sequence-display-aspect.mpg.
1245                  * issue1613, 621, 562 */
1246                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1247                     (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1248                      av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1249                     s->avctx->sample_aspect_ratio =
1250                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1251                                  (AVRational) { s->width, s->height });
1252                 } else {
1253                     s->avctx->sample_aspect_ratio =
1254                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1255                                  (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1256 // issue1613 4/3 16/9 -> 16/9
1257 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1258 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1259 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1260                     ff_dlog(avctx, "A %d/%d\n",
1261                             ff_mpeg2_aspect[s->aspect_ratio_info].num,
1262                             ff_mpeg2_aspect[s->aspect_ratio_info].den);
1263                     ff_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1264                             s->avctx->sample_aspect_ratio.den);
1265                 }
1266             } else {
1267                 s->avctx->sample_aspect_ratio =
1268                     ff_mpeg2_aspect[s->aspect_ratio_info];
1269             }
1270         } // MPEG-2
1271
1272         ff_set_sar(s->avctx, s->avctx->sample_aspect_ratio);
1273
1274         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1275         // until then pix_fmt may be changed right after codec init
1276 #if FF_API_XVMC
1277         if ((avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT ||
1278              avctx->hwaccel) && avctx->idct_algo == FF_IDCT_AUTO)
1279 #else
1280         if (avctx->hwaccel && avctx->idct_algo == FF_IDCT_AUTO)
1281 #endif /* FF_API_XVMC */
1282             avctx->idct_algo = FF_IDCT_SIMPLE;
1283
1284         /* Quantization matrices may need reordering
1285          * if DCT permutation is changed. */
1286         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1287
1288         ff_mpv_idct_init(s);
1289         if ((ret = ff_mpv_common_init(s)) < 0)
1290             return ret;
1291
1292         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1293         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1294         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1295         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1296
1297         s1->mpeg_enc_ctx_allocated = 1;
1298     }
1299     return 0;
1300 }
1301
1302 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1303                                 int buf_size)
1304 {
1305     Mpeg1Context *s1  = avctx->priv_data;
1306     MpegEncContext *s = &s1->mpeg_enc_ctx;
1307     int ref, f_code, vbv_delay;
1308
1309     init_get_bits(&s->gb, buf, buf_size * 8);
1310
1311     ref = get_bits(&s->gb, 10); /* temporal ref */
1312     s->pict_type = get_bits(&s->gb, 3);
1313     if (s->pict_type == 0 || s->pict_type > 3)
1314         return AVERROR_INVALIDDATA;
1315
1316     vbv_delay = get_bits(&s->gb, 16);
1317     if (s->pict_type == AV_PICTURE_TYPE_P ||
1318         s->pict_type == AV_PICTURE_TYPE_B) {
1319         s->full_pel[0] = get_bits1(&s->gb);
1320         f_code = get_bits(&s->gb, 3);
1321         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1322             return AVERROR_INVALIDDATA;
1323         s->mpeg_f_code[0][0] = f_code;
1324         s->mpeg_f_code[0][1] = f_code;
1325     }
1326     if (s->pict_type == AV_PICTURE_TYPE_B) {
1327         s->full_pel[1] = get_bits1(&s->gb);
1328         f_code = get_bits(&s->gb, 3);
1329         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1330             return AVERROR_INVALIDDATA;
1331         s->mpeg_f_code[1][0] = f_code;
1332         s->mpeg_f_code[1][1] = f_code;
1333     }
1334     s->current_picture.f->pict_type = s->pict_type;
1335     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1336
1337     if (avctx->debug & FF_DEBUG_PICT_INFO)
1338         av_log(avctx, AV_LOG_DEBUG,
1339                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1340
1341     s->y_dc_scale = 8;
1342     s->c_dc_scale = 8;
1343     return 0;
1344 }
1345
1346 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1347 {
1348     MpegEncContext *s = &s1->mpeg_enc_ctx;
1349     int horiz_size_ext, vert_size_ext;
1350     int bit_rate_ext;
1351
1352     skip_bits(&s->gb, 1); /* profile and level esc*/
1353     s->avctx->profile       = get_bits(&s->gb, 3);
1354     s->avctx->level         = get_bits(&s->gb, 4);
1355     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1356     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1357     horiz_size_ext          = get_bits(&s->gb, 2);
1358     vert_size_ext           = get_bits(&s->gb, 2);
1359     s->width  |= (horiz_size_ext << 12);
1360     s->height |= (vert_size_ext  << 12);
1361
1362     bit_rate_ext = get_bits(&s->gb, 12) << 18;
1363     if (bit_rate_ext < INT_MAX / 400 &&
1364         bit_rate_ext * 400 < INT_MAX - s->bit_rate) {
1365         s->bit_rate += bit_rate_ext * 400;
1366     } else {
1367         av_log(s->avctx, AV_LOG_WARNING, "Invalid bit rate extension value: %d\n",
1368                bit_rate_ext >> 18);
1369         s->bit_rate = 0;
1370     }
1371
1372     skip_bits1(&s->gb); /* marker */
1373     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1374
1375     s->low_delay = get_bits1(&s->gb);
1376     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
1377         s->low_delay = 1;
1378
1379     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1380     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1381
1382     ff_dlog(s->avctx, "sequence extension\n");
1383     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1384
1385     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1386         av_log(s->avctx, AV_LOG_DEBUG,
1387                "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1388                s->avctx->profile, s->avctx->level,
1389                s->avctx->rc_buffer_size, s->bit_rate);
1390 }
1391
1392 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1393 {
1394     MpegEncContext *s = &s1->mpeg_enc_ctx;
1395     int color_description, w, h;
1396
1397     skip_bits(&s->gb, 3); /* video format */
1398     color_description = get_bits1(&s->gb);
1399     if (color_description) {
1400         s->avctx->color_primaries = get_bits(&s->gb, 8);
1401         s->avctx->color_trc       = get_bits(&s->gb, 8);
1402         s->avctx->colorspace      = get_bits(&s->gb, 8);
1403     }
1404     w = get_bits(&s->gb, 14);
1405     skip_bits(&s->gb, 1); // marker
1406     h = get_bits(&s->gb, 14);
1407     // remaining 3 bits are zero padding
1408
1409     s1->pan_scan.width  = 16 * w;
1410     s1->pan_scan.height = 16 * h;
1411
1412     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1413         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1414 }
1415
1416 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1417 {
1418     MpegEncContext *s = &s1->mpeg_enc_ctx;
1419     int i, nofco;
1420
1421     nofco = 1;
1422     if (s->progressive_sequence) {
1423         if (s->repeat_first_field) {
1424             nofco++;
1425             if (s->top_field_first)
1426                 nofco++;
1427         }
1428     } else {
1429         if (s->picture_structure == PICT_FRAME) {
1430             nofco++;
1431             if (s->repeat_first_field)
1432                 nofco++;
1433         }
1434     }
1435     for (i = 0; i < nofco; i++) {
1436         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1437         skip_bits(&s->gb, 1); // marker
1438         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1439         skip_bits(&s->gb, 1); // marker
1440     }
1441
1442     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1443         av_log(s->avctx, AV_LOG_DEBUG,
1444                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1445                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1446                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1447                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1448 }
1449
1450 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1451                        uint16_t matrix1[64], int intra)
1452 {
1453     int i;
1454
1455     for (i = 0; i < 64; i++) {
1456         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1457         int v = get_bits(&s->gb, 8);
1458         if (v == 0) {
1459             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1460             return AVERROR_INVALIDDATA;
1461         }
1462         if (intra && i == 0 && v != 8) {
1463             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1464             v = 8; // needed by pink.mpg / issue1046
1465         }
1466         matrix0[j] = v;
1467         if (matrix1)
1468             matrix1[j] = v;
1469     }
1470     return 0;
1471 }
1472
1473 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1474 {
1475     ff_dlog(s->avctx, "matrix extension\n");
1476
1477     if (get_bits1(&s->gb))
1478         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1479     if (get_bits1(&s->gb))
1480         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1481     if (get_bits1(&s->gb))
1482         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1483     if (get_bits1(&s->gb))
1484         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1485 }
1486
1487 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1488 {
1489     MpegEncContext *s = &s1->mpeg_enc_ctx;
1490
1491     s->full_pel[0]       = s->full_pel[1] = 0;
1492     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1493     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1494     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1495     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1496     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1497         av_log(s->avctx, AV_LOG_ERROR,
1498                "Missing picture start code, guessing missing values\n");
1499         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1500             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1501                 s->pict_type = AV_PICTURE_TYPE_I;
1502             else
1503                 s->pict_type = AV_PICTURE_TYPE_P;
1504         } else
1505             s->pict_type = AV_PICTURE_TYPE_B;
1506         s->current_picture.f->pict_type = s->pict_type;
1507         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1508     }
1509     s->intra_dc_precision         = get_bits(&s->gb, 2);
1510     s->picture_structure          = get_bits(&s->gb, 2);
1511     s->top_field_first            = get_bits1(&s->gb);
1512     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1513     s->concealment_motion_vectors = get_bits1(&s->gb);
1514     s->q_scale_type               = get_bits1(&s->gb);
1515     s->intra_vlc_format           = get_bits1(&s->gb);
1516     s->alternate_scan             = get_bits1(&s->gb);
1517     s->repeat_first_field         = get_bits1(&s->gb);
1518     s->chroma_420_type            = get_bits1(&s->gb);
1519     s->progressive_frame          = get_bits1(&s->gb);
1520
1521     if (s->progressive_sequence && !s->progressive_frame) {
1522         s->progressive_frame = 1;
1523         av_log(s->avctx, AV_LOG_ERROR,
1524                "interlaced frame in progressive sequence, ignoring\n");
1525     }
1526
1527     if (s->picture_structure == 0 ||
1528         (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
1529         av_log(s->avctx, AV_LOG_ERROR,
1530                "picture_structure %d invalid, ignoring\n",
1531                s->picture_structure);
1532         s->picture_structure = PICT_FRAME;
1533     }
1534
1535     if (s->progressive_sequence && !s->frame_pred_frame_dct)
1536         av_log(s->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
1537
1538     if (s->picture_structure == PICT_FRAME) {
1539         s->v_edge_pos  = 16 * s->mb_height;
1540     } else {
1541         s->v_edge_pos   = 8 * s->mb_height;
1542         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
1543     }
1544
1545     if (s->alternate_scan) {
1546         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1547         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1548     } else {
1549         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1550         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1551     }
1552
1553     /* composite display not parsed */
1554     ff_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1555     ff_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1556     ff_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1557     ff_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1558     ff_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1559     ff_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1560     ff_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1561     ff_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1562     ff_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1563 }
1564
1565 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1566 {
1567     AVCodecContext *avctx = s->avctx;
1568     Mpeg1Context *s1      = (Mpeg1Context *) s;
1569     int ret;
1570
1571     if (s->picture_structure == PICT_FRAME)
1572         s->first_field = 0;
1573     else
1574         s->first_field ^= 1;
1575
1576     /* start frame decoding */
1577     if (s->first_field || s->picture_structure == PICT_FRAME) {
1578         AVFrameSideData *pan_scan;
1579
1580         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1581             return ret;
1582
1583         ff_mpeg_er_frame_start(s);
1584
1585         /* first check if we must repeat the frame */
1586         s->current_picture_ptr->f->repeat_pict = 0;
1587         if (s->repeat_first_field) {
1588             if (s->progressive_sequence) {
1589                 if (s->top_field_first)
1590                     s->current_picture_ptr->f->repeat_pict = 4;
1591                 else
1592                     s->current_picture_ptr->f->repeat_pict = 2;
1593             } else if (s->progressive_frame) {
1594                 s->current_picture_ptr->f->repeat_pict = 1;
1595             }
1596         }
1597
1598         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1599                                           AV_FRAME_DATA_PANSCAN,
1600                                           sizeof(s1->pan_scan));
1601         if (!pan_scan)
1602             return AVERROR(ENOMEM);
1603         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1604
1605         if (s1->a53_caption) {
1606             AVFrameSideData *sd = av_frame_new_side_data(
1607                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1608                 s1->a53_caption_size);
1609             if (sd)
1610                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1611             av_freep(&s1->a53_caption);
1612         }
1613
1614         if (s1->has_stereo3d) {
1615             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1616             if (!stereo)
1617                 return AVERROR(ENOMEM);
1618
1619             *stereo = s1->stereo3d;
1620             s1->has_stereo3d = 0;
1621         }
1622
1623         if (s1->has_afd) {
1624             AVFrameSideData *sd =
1625                 av_frame_new_side_data(s->current_picture_ptr->f,
1626                                        AV_FRAME_DATA_AFD, 1);
1627             if (!sd)
1628                 return AVERROR(ENOMEM);
1629
1630             *sd->data   = s1->afd;
1631             s1->has_afd = 0;
1632         }
1633
1634         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1635             ff_thread_finish_setup(avctx);
1636     } else { // second field
1637         int i;
1638
1639         if (!s->current_picture_ptr) {
1640             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1641             return AVERROR_INVALIDDATA;
1642         }
1643
1644         if (s->avctx->hwaccel &&
1645             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1646             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1647                 av_log(avctx, AV_LOG_ERROR,
1648                        "hardware accelerator failed to decode first field\n");
1649         }
1650
1651         for (i = 0; i < 4; i++) {
1652             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1653             if (s->picture_structure == PICT_BOTTOM_FIELD)
1654                 s->current_picture.f->data[i] +=
1655                     s->current_picture_ptr->f->linesize[i];
1656         }
1657     }
1658
1659     if (avctx->hwaccel) {
1660         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1661             return ret;
1662     }
1663
1664 #if FF_API_XVMC
1665 FF_DISABLE_DEPRECATION_WARNINGS
1666 // ff_mpv_frame_start will call this function too,
1667 // but we need to call it on every field
1668     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1669         if (ff_xvmc_field_start(s, avctx) < 0)
1670             return -1;
1671 FF_ENABLE_DEPRECATION_WARNINGS
1672 #endif /* FF_API_XVMC */
1673
1674     return 0;
1675 }
1676
1677 #define DECODE_SLICE_ERROR -1
1678 #define DECODE_SLICE_OK     0
1679
1680 /**
1681  * Decode a slice.
1682  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1683  * @return DECODE_SLICE_ERROR if the slice is damaged,
1684  *         DECODE_SLICE_OK if this slice is OK
1685  */
1686 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1687                              const uint8_t **buf, int buf_size)
1688 {
1689     AVCodecContext *avctx = s->avctx;
1690     const int field_pic   = s->picture_structure != PICT_FRAME;
1691     int ret;
1692
1693     s->resync_mb_x =
1694     s->resync_mb_y = -1;
1695
1696     assert(mb_y < s->mb_height);
1697
1698     init_get_bits(&s->gb, *buf, buf_size * 8);
1699
1700     ff_mpeg1_clean_buffers(s);
1701     s->interlaced_dct = 0;
1702
1703     s->qscale = get_qscale(s);
1704
1705     if (s->qscale == 0) {
1706         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1707         return AVERROR_INVALIDDATA;
1708     }
1709
1710     /* extra slice info */
1711     while (get_bits1(&s->gb) != 0)
1712         skip_bits(&s->gb, 8);
1713
1714     s->mb_x = 0;
1715
1716     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1717         skip_bits1(&s->gb);
1718     } else {
1719         while (get_bits_left(&s->gb) > 0) {
1720             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1721                                 MBINCR_VLC_BITS, 2);
1722             if (code < 0) {
1723                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1724                 return AVERROR_INVALIDDATA;
1725             }
1726             if (code >= 33) {
1727                 if (code == 33)
1728                     s->mb_x += 33;
1729                 /* otherwise, stuffing, nothing to do */
1730             } else {
1731                 s->mb_x += code;
1732                 break;
1733             }
1734         }
1735     }
1736
1737     if (s->mb_x >= (unsigned) s->mb_width) {
1738         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1739         return AVERROR_INVALIDDATA;
1740     }
1741
1742     if (avctx->hwaccel) {
1743         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1744         int start_code = -1;
1745         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1746         if (buf_end < *buf + buf_size)
1747             buf_end -= 4;
1748         s->mb_y = mb_y;
1749         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1750             return DECODE_SLICE_ERROR;
1751         *buf = buf_end;
1752         return DECODE_SLICE_OK;
1753     }
1754
1755     s->resync_mb_x = s->mb_x;
1756     s->resync_mb_y = s->mb_y = mb_y;
1757     s->mb_skip_run = 0;
1758     ff_init_block_index(s);
1759
1760     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1761         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1762             av_log(s->avctx, AV_LOG_DEBUG,
1763                    "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n",
1764                    s->qscale,
1765                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1766                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1767                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1768                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1769                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1770                    s->progressive_sequence ? "ps"  : "",
1771                    s->progressive_frame    ? "pf"  : "",
1772                    s->alternate_scan       ? "alt" : "",
1773                    s->top_field_first      ? "top" : "",
1774                    s->intra_dc_precision, s->picture_structure,
1775                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1776                    s->q_scale_type, s->intra_vlc_format,
1777                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1778         }
1779     }
1780
1781     for (;;) {
1782 #if FF_API_XVMC
1783 FF_DISABLE_DEPRECATION_WARNINGS
1784         // If 1, we memcpy blocks in xvmcvideo.
1785         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1786             ff_xvmc_init_block(s); // set s->block
1787 FF_ENABLE_DEPRECATION_WARNINGS
1788 #endif /* FF_API_XVMC */
1789
1790         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1791             return ret;
1792
1793         // Note motion_val is normally NULL unless we want to extract the MVs.
1794         if (s->current_picture.motion_val[0] && !s->encoding) {
1795             const int wrap = s->b8_stride;
1796             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1797             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1798             int motion_x, motion_y, dir, i;
1799
1800             for (i = 0; i < 2; i++) {
1801                 for (dir = 0; dir < 2; dir++) {
1802                     if (s->mb_intra ||
1803                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1804                         motion_x = motion_y = 0;
1805                     } else if (s->mv_type == MV_TYPE_16X16 ||
1806                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1807                         motion_x = s->mv[dir][0][0];
1808                         motion_y = s->mv[dir][0][1];
1809                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1810                         motion_x = s->mv[dir][i][0];
1811                         motion_y = s->mv[dir][i][1];
1812                     }
1813
1814                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1815                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1816                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1817                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1818                     s->current_picture.ref_index [dir][b8_xy]     =
1819                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1820                     assert(s->field_select[dir][i] == 0 ||
1821                            s->field_select[dir][i] == 1);
1822                 }
1823                 xy    += wrap;
1824                 b8_xy += 2;
1825             }
1826         }
1827
1828         s->dest[0] += 16;
1829         s->dest[1] += 16 >> s->chroma_x_shift;
1830         s->dest[2] += 16 >> s->chroma_x_shift;
1831
1832         ff_mpv_decode_mb(s, s->block);
1833
1834         if (++s->mb_x >= s->mb_width) {
1835             const int mb_size = 16;
1836
1837             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1838             ff_mpv_report_decode_progress(s);
1839
1840             s->mb_x  = 0;
1841             s->mb_y += 1 << field_pic;
1842
1843             if (s->mb_y >= s->mb_height) {
1844                 int left   = get_bits_left(&s->gb);
1845                 int is_d10 = s->chroma_format == 2 &&
1846                              s->pict_type == AV_PICTURE_TYPE_I &&
1847                              avctx->profile == 0 && avctx->level == 5 &&
1848                              s->intra_dc_precision == 2 &&
1849                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1850                              s->progressive_frame == 0
1851                              /* vbv_delay == 0xBBB || 0xE10 */;
1852
1853                 if (left < 0 ||
1854                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1855                     ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
1856                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1857                            left, show_bits(&s->gb, FFMIN(left, 23)));
1858                     return AVERROR_INVALIDDATA;
1859                 } else
1860                     goto eos;
1861             }
1862
1863             ff_init_block_index(s);
1864         }
1865
1866         /* skip mb handling */
1867         if (s->mb_skip_run == -1) {
1868             /* read increment again */
1869             s->mb_skip_run = 0;
1870             for (;;) {
1871                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1872                                     MBINCR_VLC_BITS, 2);
1873                 if (code < 0) {
1874                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1875                     return AVERROR_INVALIDDATA;
1876                 }
1877                 if (code >= 33) {
1878                     if (code == 33) {
1879                         s->mb_skip_run += 33;
1880                     } else if (code == 35) {
1881                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1882                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1883                             return AVERROR_INVALIDDATA;
1884                         }
1885                         goto eos; /* end of slice */
1886                     }
1887                     /* otherwise, stuffing, nothing to do */
1888                 } else {
1889                     s->mb_skip_run += code;
1890                     break;
1891                 }
1892             }
1893             if (s->mb_skip_run) {
1894                 int i;
1895                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1896                     av_log(s->avctx, AV_LOG_ERROR,
1897                            "skipped MB in I-frame at %d %d\n", s->mb_x, s->mb_y);
1898                     return AVERROR_INVALIDDATA;
1899                 }
1900
1901                 /* skip mb */
1902                 s->mb_intra = 0;
1903                 for (i = 0; i < 12; i++)
1904                     s->block_last_index[i] = -1;
1905                 if (s->picture_structure == PICT_FRAME)
1906                     s->mv_type = MV_TYPE_16X16;
1907                 else
1908                     s->mv_type = MV_TYPE_FIELD;
1909                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1910                     /* if P type, zero motion vector is implied */
1911                     s->mv_dir             = MV_DIR_FORWARD;
1912                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1913                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1914                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1915                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1916                 } else {
1917                     /* if B type, reuse previous vectors and directions */
1918                     s->mv[0][0][0] = s->last_mv[0][0][0];
1919                     s->mv[0][0][1] = s->last_mv[0][0][1];
1920                     s->mv[1][0][0] = s->last_mv[1][0][0];
1921                     s->mv[1][0][1] = s->last_mv[1][0][1];
1922                 }
1923             }
1924         }
1925     }
1926 eos: // end of slice
1927     *buf += (get_bits_count(&s->gb) - 1) / 8;
1928     ff_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1929     return 0;
1930 }
1931
1932 static int slice_decode_thread(AVCodecContext *c, void *arg)
1933 {
1934     MpegEncContext *s   = *(void **) arg;
1935     const uint8_t *buf  = s->gb.buffer;
1936     int mb_y            = s->start_mb_y;
1937     const int field_pic = s->picture_structure != PICT_FRAME;
1938
1939     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1940
1941     for (;;) {
1942         uint32_t start_code;
1943         int ret;
1944
1945         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1946         emms_c();
1947         ff_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1948                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
1949                 s->start_mb_y, s->end_mb_y, s->er.error_count);
1950         if (ret < 0) {
1951             if (c->err_recognition & AV_EF_EXPLODE)
1952                 return ret;
1953             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1954                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
1955                                 s->mb_x, s->mb_y,
1956                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
1957         } else {
1958             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
1959                             s->mb_x - 1, s->mb_y,
1960                             ER_AC_END | ER_DC_END | ER_MV_END);
1961         }
1962
1963         if (s->mb_y == s->end_mb_y)
1964             return 0;
1965
1966         start_code = -1;
1967         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
1968         mb_y       = (start_code - SLICE_MIN_START_CODE) << field_pic;
1969         if (s->picture_structure == PICT_BOTTOM_FIELD)
1970             mb_y++;
1971         if (mb_y < 0 || mb_y >= s->end_mb_y)
1972             return AVERROR_INVALIDDATA;
1973     }
1974 }
1975
1976 /**
1977  * Handle slice ends.
1978  * @return 1 if it seems to be the last slice
1979  */
1980 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1981 {
1982     Mpeg1Context *s1  = avctx->priv_data;
1983     MpegEncContext *s = &s1->mpeg_enc_ctx;
1984
1985     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1986         return 0;
1987
1988     if (s->avctx->hwaccel) {
1989         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1990             av_log(avctx, AV_LOG_ERROR,
1991                    "hardware accelerator failed to decode picture\n");
1992     }
1993
1994 #if FF_API_XVMC
1995 FF_DISABLE_DEPRECATION_WARNINGS
1996     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1997         ff_xvmc_field_end(s);
1998 FF_ENABLE_DEPRECATION_WARNINGS
1999 #endif /* FF_API_XVMC */
2000
2001     /* end of slice reached */
2002     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field) {
2003         /* end of image */
2004
2005         ff_er_frame_end(&s->er);
2006
2007         ff_mpv_frame_end(s);
2008
2009         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2010             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2011             if (ret < 0)
2012                 return ret;
2013             ff_print_debug_info(s, s->current_picture_ptr);
2014         } else {
2015             if (avctx->active_thread_type & FF_THREAD_FRAME)
2016                 s->picture_number++;
2017             /* latency of 1 frame for I- and P-frames */
2018             /* XXX: use another variable than picture_number */
2019             if (s->last_picture_ptr) {
2020                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2021                 if (ret < 0)
2022                     return ret;
2023                 ff_print_debug_info(s, s->last_picture_ptr);
2024             }
2025         }
2026
2027         return 1;
2028     } else {
2029         return 0;
2030     }
2031 }
2032
2033 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2034                                  const uint8_t *buf, int buf_size)
2035 {
2036     Mpeg1Context *s1  = avctx->priv_data;
2037     MpegEncContext *s = &s1->mpeg_enc_ctx;
2038     int width, height;
2039     int i, v, j;
2040
2041     init_get_bits(&s->gb, buf, buf_size * 8);
2042
2043     width  = get_bits(&s->gb, 12);
2044     height = get_bits(&s->gb, 12);
2045     if (width == 0 || height == 0) {
2046         av_log(avctx, AV_LOG_WARNING,
2047                "Invalid horizontal or vertical size value.\n");
2048         if (avctx->err_recognition & AV_EF_BITSTREAM)
2049             return AVERROR_INVALIDDATA;
2050     }
2051     s->aspect_ratio_info = get_bits(&s->gb, 4);
2052     if (s->aspect_ratio_info == 0) {
2053         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2054         if (avctx->err_recognition & AV_EF_BITSTREAM)
2055             return AVERROR_INVALIDDATA;
2056     }
2057     s->frame_rate_index = get_bits(&s->gb, 4);
2058     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2059         av_log(avctx, AV_LOG_WARNING,
2060                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2061         return AVERROR_INVALIDDATA;
2062     }
2063     s->bit_rate = get_bits(&s->gb, 18) * 400;
2064     if (get_bits1(&s->gb) == 0) { /* marker */
2065         av_log(avctx, AV_LOG_ERROR, "Marker in sequence header missing\n");
2066         return AVERROR_INVALIDDATA;
2067     }
2068     s->width  = width;
2069     s->height = height;
2070
2071     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2072     skip_bits(&s->gb, 1);
2073
2074     /* get matrix */
2075     if (get_bits1(&s->gb)) {
2076         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2077     } else {
2078         for (i = 0; i < 64; i++) {
2079             j = s->idsp.idct_permutation[i];
2080             v = ff_mpeg1_default_intra_matrix[i];
2081             s->intra_matrix[j]        = v;
2082             s->chroma_intra_matrix[j] = v;
2083         }
2084     }
2085     if (get_bits1(&s->gb)) {
2086         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2087     } else {
2088         for (i = 0; i < 64; i++) {
2089             int j = s->idsp.idct_permutation[i];
2090             v = ff_mpeg1_default_non_intra_matrix[i];
2091             s->inter_matrix[j]        = v;
2092             s->chroma_inter_matrix[j] = v;
2093         }
2094     }
2095
2096     if (show_bits(&s->gb, 23) != 0) {
2097         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2098         return AVERROR_INVALIDDATA;
2099     }
2100
2101     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2102     s->progressive_sequence = 1;
2103     s->progressive_frame    = 1;
2104     s->picture_structure    = PICT_FRAME;
2105     s->frame_pred_frame_dct = 1;
2106     s->chroma_format        = 1;
2107     s->codec_id             =
2108     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2109     s->out_format           = FMT_MPEG1;
2110     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
2111         s->low_delay = 1;
2112
2113     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2114         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2115                s->avctx->rc_buffer_size, s->bit_rate);
2116
2117     return 0;
2118 }
2119
2120 static int vcr2_init_sequence(AVCodecContext *avctx)
2121 {
2122     Mpeg1Context *s1  = avctx->priv_data;
2123     MpegEncContext *s = &s1->mpeg_enc_ctx;
2124     int i, v, ret;
2125
2126     /* start new MPEG-1 context decoding */
2127     s->out_format = FMT_MPEG1;
2128     if (s1->mpeg_enc_ctx_allocated) {
2129         ff_mpv_common_end(s);
2130     }
2131     s->width            = avctx->coded_width;
2132     s->height           = avctx->coded_height;
2133     avctx->has_b_frames = 0; // true?
2134     s->low_delay        = 1;
2135
2136     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2137
2138 #if FF_API_XVMC
2139     if ((avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel) &&
2140         avctx->idct_algo == FF_IDCT_AUTO)
2141 #else
2142     if (avctx->hwaccel && avctx->idct_algo == FF_IDCT_AUTO)
2143 #endif /* FF_API_XVMC */
2144         avctx->idct_algo = FF_IDCT_SIMPLE;
2145
2146     ff_mpv_idct_init(s);
2147     if ((ret = ff_mpv_common_init(s)) < 0)
2148         return ret;
2149     s1->mpeg_enc_ctx_allocated = 1;
2150
2151     for (i = 0; i < 64; i++) {
2152         int j = s->idsp.idct_permutation[i];
2153         v = ff_mpeg1_default_intra_matrix[i];
2154         s->intra_matrix[j]        = v;
2155         s->chroma_intra_matrix[j] = v;
2156
2157         v = ff_mpeg1_default_non_intra_matrix[i];
2158         s->inter_matrix[j]        = v;
2159         s->chroma_inter_matrix[j] = v;
2160     }
2161
2162     s->progressive_sequence  = 1;
2163     s->progressive_frame     = 1;
2164     s->picture_structure     = PICT_FRAME;
2165     s->frame_pred_frame_dct  = 1;
2166     s->chroma_format         = 1;
2167     s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2168     s1->save_width           = s->width;
2169     s1->save_height          = s->height;
2170     s1->save_progressive_seq = s->progressive_sequence;
2171     return 0;
2172 }
2173
2174 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2175                               const uint8_t *p, int buf_size)
2176 {
2177     Mpeg1Context *s1 = avctx->priv_data;
2178
2179     if (buf_size >= 6 &&
2180         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2181         p[4] == 3 && (p[5] & 0x40)) {
2182         /* extract A53 Part 4 CC data */
2183         int cc_count = p[5] & 0x1f;
2184         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2185             av_freep(&s1->a53_caption);
2186             s1->a53_caption_size = cc_count * 3;
2187             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2188             if (s1->a53_caption)
2189                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2190         }
2191         return 1;
2192     } else if (buf_size >= 11 &&
2193                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2194         /* extract DVD CC data */
2195         int cc_count = 0;
2196         int i;
2197         // There is a caption count field in the data, but it is often
2198         // incorrect.  So count the number of captions present.
2199         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2200             cc_count++;
2201         // Transform the DVD format into A53 Part 4 format
2202         if (cc_count > 0) {
2203             av_freep(&s1->a53_caption);
2204             s1->a53_caption_size = cc_count * 6;
2205             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2206             if (s1->a53_caption) {
2207                 uint8_t field1 = !!(p[4] & 0x80);
2208                 uint8_t *cap = s1->a53_caption;
2209                 p += 5;
2210                 for (i = 0; i < cc_count; i++) {
2211                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2212                     cap[1] = p[1];
2213                     cap[2] = p[2];
2214                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2215                     cap[4] = p[4];
2216                     cap[5] = p[5];
2217                     cap += 6;
2218                     p += 6;
2219                 }
2220             }
2221         }
2222         return 1;
2223     }
2224     return 0;
2225 }
2226
2227 static void mpeg_decode_user_data(AVCodecContext *avctx,
2228                                   const uint8_t *p, int buf_size)
2229 {
2230     const uint8_t *buf_end = p + buf_size;
2231     Mpeg1Context *s1 = avctx->priv_data;
2232
2233     /* we parse the DTG active format information */
2234     if (buf_end - p >= 5 &&
2235         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2236         int flags = p[4];
2237         p += 5;
2238         if (flags & 0x80) {
2239             /* skip event id */
2240             p += 2;
2241         }
2242         if (flags & 0x40) {
2243             if (buf_end - p < 1)
2244                 return;
2245 #if FF_API_AFD
2246 FF_DISABLE_DEPRECATION_WARNINGS
2247             avctx->dtg_active_format = p[0] & 0x0f;
2248 FF_ENABLE_DEPRECATION_WARNINGS
2249 #endif /* FF_API_AFD */
2250             s1->has_afd = 1;
2251             s1->afd     = p[0] & 0x0f;
2252         }
2253     } else if (buf_end - p >= 6 &&
2254                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2255                p[4] == 0x03) { // S3D_video_format_length
2256         // the 0x7F mask ignores the reserved_bit value
2257         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2258
2259         if (S3D_video_format_type == 0x03 ||
2260             S3D_video_format_type == 0x04 ||
2261             S3D_video_format_type == 0x08 ||
2262             S3D_video_format_type == 0x23) {
2263
2264             s1->has_stereo3d = 1;
2265
2266             switch (S3D_video_format_type) {
2267             case 0x03:
2268                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2269                 break;
2270             case 0x04:
2271                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2272                 break;
2273             case 0x08:
2274                 s1->stereo3d.type = AV_STEREO3D_2D;
2275                 break;
2276             case 0x23:
2277                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2278                 break;
2279             }
2280         }
2281     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2282         return;
2283     }
2284 }
2285
2286 static void mpeg_decode_gop(AVCodecContext *avctx,
2287                             const uint8_t *buf, int buf_size)
2288 {
2289     Mpeg1Context *s1  = avctx->priv_data;
2290     MpegEncContext *s = &s1->mpeg_enc_ctx;
2291
2292     int time_code_hours, time_code_minutes;
2293     int time_code_seconds, time_code_pictures;
2294     int broken_link;
2295
2296     init_get_bits(&s->gb, buf, buf_size * 8);
2297
2298     skip_bits1(&s->gb); /* drop_frame_flag */
2299
2300     time_code_hours   = get_bits(&s->gb, 5);
2301     time_code_minutes = get_bits(&s->gb, 6);
2302     skip_bits1(&s->gb); // marker bit
2303     time_code_seconds  = get_bits(&s->gb, 6);
2304     time_code_pictures = get_bits(&s->gb, 6);
2305
2306     s1->closed_gop = get_bits1(&s->gb);
2307     /* broken_link indicate that after editing the
2308      * reference frames of the first B-Frames after GOP I-Frame
2309      * are missing (open gop) */
2310     broken_link = get_bits1(&s->gb);
2311
2312     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2313         av_log(s->avctx, AV_LOG_DEBUG,
2314                "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2315                time_code_hours, time_code_minutes, time_code_seconds,
2316                time_code_pictures, s1->closed_gop, broken_link);
2317 }
2318
2319 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2320                          int *got_output, const uint8_t *buf, int buf_size)
2321 {
2322     Mpeg1Context *s = avctx->priv_data;
2323     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2324     const uint8_t *buf_ptr = buf;
2325     const uint8_t *buf_end = buf + buf_size;
2326     int ret, input_size;
2327     int last_code = 0, skip_frame = 0;
2328
2329     for (;;) {
2330         /* find next start code */
2331         uint32_t start_code = -1;
2332         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2333         if (start_code > 0x1ff) {
2334             if (!skip_frame) {
2335                 if (HAVE_THREADS &&
2336                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2337                     !avctx->hwaccel) {
2338                     int i;
2339
2340                     avctx->execute(avctx, slice_decode_thread,
2341                                    &s2->thread_context[0], NULL,
2342                                    s->slice_count, sizeof(void *));
2343                     for (i = 0; i < s->slice_count; i++)
2344                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2345                 }
2346
2347                 ret = slice_end(avctx, picture);
2348                 if (ret < 0)
2349                     return ret;
2350                 else if (ret) {
2351                     // FIXME: merge with the stuff in mpeg_decode_slice
2352                     if (s2->last_picture_ptr || s2->low_delay)
2353                         *got_output = 1;
2354                 }
2355             }
2356             s2->pict_type = 0;
2357             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2358         }
2359
2360         input_size = buf_end - buf_ptr;
2361
2362         if (avctx->debug & FF_DEBUG_STARTCODE)
2363             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %td left %d\n",
2364                    start_code, buf_ptr - buf, input_size);
2365
2366         /* prepare data for next start code */
2367         switch (start_code) {
2368         case SEQ_START_CODE:
2369             if (last_code == 0) {
2370                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2371                 s->sync = 1;
2372             } else {
2373                 av_log(avctx, AV_LOG_ERROR,
2374                        "ignoring SEQ_START_CODE after %X\n", last_code);
2375                 if (avctx->err_recognition & AV_EF_EXPLODE)
2376                     return AVERROR_INVALIDDATA;
2377             }
2378             break;
2379
2380         case PICTURE_START_CODE:
2381             if (s2->width <= 0 || s2->height <= 0) {
2382                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2383                        s2->width, s2->height);
2384                 return AVERROR_INVALIDDATA;
2385             }
2386
2387             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2388                 !avctx->hwaccel && s->slice_count) {
2389                 int i;
2390
2391                 avctx->execute(avctx, slice_decode_thread,
2392                                s2->thread_context, NULL,
2393                                s->slice_count, sizeof(void *));
2394                 for (i = 0; i < s->slice_count; i++)
2395                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2396                 s->slice_count = 0;
2397             }
2398             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2399                 ret = mpeg_decode_postinit(avctx);
2400                 if (ret < 0) {
2401                     av_log(avctx, AV_LOG_ERROR,
2402                            "mpeg_decode_postinit() failure\n");
2403                     return ret;
2404                 }
2405
2406                 /* We have a complete image: we try to decompress it. */
2407                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2408                     s2->pict_type = 0;
2409                 s->first_slice = 1;
2410                 last_code      = PICTURE_START_CODE;
2411             } else {
2412                 av_log(avctx, AV_LOG_ERROR,
2413                        "ignoring pic after %X\n", last_code);
2414                 if (avctx->err_recognition & AV_EF_EXPLODE)
2415                     return AVERROR_INVALIDDATA;
2416             }
2417             break;
2418         case EXT_START_CODE:
2419             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2420
2421             switch (get_bits(&s2->gb, 4)) {
2422             case 0x1:
2423                 if (last_code == 0) {
2424                     mpeg_decode_sequence_extension(s);
2425                 } else {
2426                     av_log(avctx, AV_LOG_ERROR,
2427                            "ignoring seq ext after %X\n", last_code);
2428                     if (avctx->err_recognition & AV_EF_EXPLODE)
2429                         return AVERROR_INVALIDDATA;
2430                 }
2431                 break;
2432             case 0x2:
2433                 mpeg_decode_sequence_display_extension(s);
2434                 break;
2435             case 0x3:
2436                 mpeg_decode_quant_matrix_extension(s2);
2437                 break;
2438             case 0x7:
2439                 mpeg_decode_picture_display_extension(s);
2440                 break;
2441             case 0x8:
2442                 if (last_code == PICTURE_START_CODE) {
2443                     mpeg_decode_picture_coding_extension(s);
2444                 } else {
2445                     av_log(avctx, AV_LOG_ERROR,
2446                            "ignoring pic cod ext after %X\n", last_code);
2447                     if (avctx->err_recognition & AV_EF_EXPLODE)
2448                         return AVERROR_INVALIDDATA;
2449                 }
2450                 break;
2451             }
2452             break;
2453         case USER_START_CODE:
2454             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2455             break;
2456         case GOP_START_CODE:
2457             if (last_code == 0) {
2458                 s2->first_field = 0;
2459                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2460                 s->sync = 1;
2461             } else {
2462                 av_log(avctx, AV_LOG_ERROR,
2463                        "ignoring GOP_START_CODE after %X\n", last_code);
2464                 if (avctx->err_recognition & AV_EF_EXPLODE)
2465                     return AVERROR_INVALIDDATA;
2466             }
2467             break;
2468         default:
2469             if (start_code >= SLICE_MIN_START_CODE &&
2470                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2471                 const int field_pic = s2->picture_structure != PICT_FRAME;
2472                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
2473                 last_code = SLICE_MIN_START_CODE;
2474
2475                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2476                     mb_y++;
2477
2478                 if (mb_y >= s2->mb_height) {
2479                     av_log(s2->avctx, AV_LOG_ERROR,
2480                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2481                     return AVERROR_INVALIDDATA;
2482                 }
2483
2484                 if (!s2->last_picture_ptr) {
2485                     /* Skip B-frames if we do not have reference frames and
2486                      * GOP is not closed. */
2487                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2488                         if (!s->closed_gop) {
2489                             skip_frame = 1;
2490                             break;
2491                         }
2492                     }
2493                 }
2494                 if (s2->pict_type == AV_PICTURE_TYPE_I)
2495                     s->sync = 1;
2496                 if (!s2->next_picture_ptr) {
2497                     /* Skip P-frames if we do not have a reference frame or
2498                      * we have an invalid header. */
2499                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2500                         skip_frame = 1;
2501                         break;
2502                     }
2503                 }
2504                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2505                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2506                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2507                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2508                     avctx->skip_frame >= AVDISCARD_ALL) {
2509                     skip_frame = 1;
2510                     break;
2511                 }
2512
2513                 if (!s->mpeg_enc_ctx_allocated)
2514                     break;
2515
2516                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2517                     if (mb_y < avctx->skip_top ||
2518                         mb_y >= s2->mb_height - avctx->skip_bottom)
2519                         break;
2520                 }
2521
2522                 if (!s2->pict_type) {
2523                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2524                     if (avctx->err_recognition & AV_EF_EXPLODE)
2525                         return AVERROR_INVALIDDATA;
2526                     break;
2527                 }
2528
2529                 if (s->first_slice) {
2530                     skip_frame     = 0;
2531                     s->first_slice = 0;
2532                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2533                         return ret;
2534                 }
2535                 if (!s2->current_picture_ptr) {
2536                     av_log(avctx, AV_LOG_ERROR,
2537                            "current_picture not initialized\n");
2538                     return AVERROR_INVALIDDATA;
2539                 }
2540
2541                 if (HAVE_THREADS &&
2542                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2543                     !avctx->hwaccel) {
2544                     int threshold = (s2->mb_height * s->slice_count +
2545                                      s2->slice_context_count / 2) /
2546                                     s2->slice_context_count;
2547                     if (threshold <= mb_y) {
2548                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2549
2550                         thread_context->start_mb_y = mb_y;
2551                         thread_context->end_mb_y   = s2->mb_height;
2552                         if (s->slice_count) {
2553                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2554                             ret = ff_update_duplicate_context(thread_context, s2);
2555                             if (ret < 0)
2556                                 return ret;
2557                         }
2558                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2559                         s->slice_count++;
2560                     }
2561                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2562                 } else {
2563                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2564                     emms_c();
2565
2566                     if (ret < 0) {
2567                         if (avctx->err_recognition & AV_EF_EXPLODE)
2568                             return ret;
2569                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2570                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2571                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2572                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2573                     } else {
2574                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2575                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2576                                         ER_AC_END | ER_DC_END | ER_MV_END);
2577                     }
2578                 }
2579             }
2580             break;
2581         }
2582     }
2583 }
2584
2585 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2586                              int *got_output, AVPacket *avpkt)
2587 {
2588     const uint8_t *buf = avpkt->data;
2589     int buf_size = avpkt->size;
2590     Mpeg1Context *s = avctx->priv_data;
2591     AVFrame *picture = data;
2592     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2593     ff_dlog(avctx, "fill_buffer\n");
2594
2595     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2596         /* special case for last picture */
2597         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2598             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2599             if (ret < 0)
2600                 return ret;
2601
2602             s2->next_picture_ptr = NULL;
2603
2604             *got_output = 1;
2605         }
2606         return buf_size;
2607     }
2608
2609     if (s2->avctx->flags & AV_CODEC_FLAG_TRUNCATED) {
2610         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2611                                            buf_size, NULL);
2612
2613         if (ff_combine_frame(&s2->parse_context, next,
2614                              (const uint8_t **) &buf, &buf_size) < 0)
2615             return buf_size;
2616     }
2617
2618     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
2619         vcr2_init_sequence(avctx);
2620
2621     s->slice_count = 0;
2622
2623     if (avctx->extradata && !s->extradata_decoded) {
2624         int ret = decode_chunks(avctx, picture, got_output,
2625                                 avctx->extradata, avctx->extradata_size);
2626         s->extradata_decoded = 1;
2627         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2628             return ret;
2629     }
2630
2631     return decode_chunks(avctx, picture, got_output, buf, buf_size);
2632 }
2633
2634 static void flush(AVCodecContext *avctx)
2635 {
2636     Mpeg1Context *s = avctx->priv_data;
2637
2638     s->sync       = 0;
2639     s->closed_gop = 0;
2640
2641     ff_mpeg_flush(avctx);
2642 }
2643
2644 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2645 {
2646     Mpeg1Context *s = avctx->priv_data;
2647
2648     if (s->mpeg_enc_ctx_allocated)
2649         ff_mpv_common_end(&s->mpeg_enc_ctx);
2650     av_freep(&s->a53_caption);
2651     return 0;
2652 }
2653
2654 AVCodec ff_mpeg1video_decoder = {
2655     .name                  = "mpeg1video",
2656     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2657     .type                  = AVMEDIA_TYPE_VIDEO,
2658     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2659     .priv_data_size        = sizeof(Mpeg1Context),
2660     .init                  = mpeg_decode_init,
2661     .close                 = mpeg_decode_end,
2662     .decode                = mpeg_decode_frame,
2663     .capabilities          = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2664                              AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2665                              AV_CODEC_CAP_SLICE_THREADS,
2666     .flush                 = flush,
2667     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2668 };
2669
2670 AVCodec ff_mpeg2video_decoder = {
2671     .name           = "mpeg2video",
2672     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2673     .type           = AVMEDIA_TYPE_VIDEO,
2674     .id             = AV_CODEC_ID_MPEG2VIDEO,
2675     .priv_data_size = sizeof(Mpeg1Context),
2676     .init           = mpeg_decode_init,
2677     .close          = mpeg_decode_end,
2678     .decode         = mpeg_decode_frame,
2679     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2680                       AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2681                       AV_CODEC_CAP_SLICE_THREADS,
2682     .flush          = flush,
2683     .profiles       = NULL_IF_CONFIG_SMALL(ff_mpeg2_video_profiles),
2684 };
2685
2686 #if FF_API_XVMC
2687 #if CONFIG_MPEG_XVMC_DECODER
2688 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2689 {
2690     if (avctx->active_thread_type & FF_THREAD_SLICE)
2691         return -1;
2692     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2693         return -1;
2694     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2695         ff_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2696     }
2697     mpeg_decode_init(avctx);
2698
2699     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2700     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2701
2702     return 0;
2703 }
2704
2705 AVCodec ff_mpeg_xvmc_decoder = {
2706     .name           = "mpegvideo_xvmc",
2707     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2708     .type           = AVMEDIA_TYPE_VIDEO,
2709     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2710     .priv_data_size = sizeof(Mpeg1Context),
2711     .init           = mpeg_mc_decode_init,
2712     .close          = mpeg_decode_end,
2713     .decode         = mpeg_decode_frame,
2714     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2715                       AV_CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL |
2716                       AV_CODEC_CAP_DELAY,
2717     .flush          = flush,
2718 };
2719
2720 #endif
2721 #endif /* FF_API_XVMC */