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   1 /*
   2  * MPEG-1/2 decoder
   3  * Copyright (c) 2000, 2001 Fabrice Bellard
   4  * Copyright (c) 2002-2013 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file
  25  * MPEG-1/2 decoder
  26  */
  27
  28 #define UNCHECKED_BITSTREAM_READER 1
  29 #include <inttypes.h>
  30
  31 #include "libavutil/attributes.h"
  32 #include "libavutil/imgutils.h"
  33 #include "libavutil/internal.h"
  34 #include "libavutil/stereo3d.h"
  35
  36 #include "avcodec.h"
  37 #include "bytestream.h"
  38 #include "error_resilience.h"
  39 #include "hwconfig.h"
  40 #include "idctdsp.h"
  41 #include "internal.h"
  42 #include "mpeg_er.h"
  43 #include "mpeg12.h"
  44 #include "mpeg12data.h"
  45 #include "mpegutils.h"
  46 #include "mpegvideo.h"
  47 #include "mpegvideodata.h"
  48 #include "profiles.h"
  49 #include "thread.h"
  50 #include "version.h"
  51 #include "xvmc_internal.h"
  52
  53 typedef struct Mpeg1Context {
  54     MpegEncContext mpeg_enc_ctx;
  55     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  56     int repeat_field;           /* true if we must repeat the field */
  57     AVPanScan pan_scan;         /* some temporary storage for the panscan */
  58     AVStereo3D stereo3d;
  59     int has_stereo3d;
  60     uint8_t *a53_caption;
  61     int a53_caption_size;
  62     uint8_t afd;
  63     int has_afd;
  64     int slice_count;
  65     AVRational save_aspect;
  66     int save_width, save_height, save_progressive_seq;
  67     int rc_buffer_size;
  68     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
  69     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
  70     int tmpgexs;
  71     int first_slice;
  72     int extradata_decoded;
  73 } Mpeg1Context;
  74
  75 #define MB_TYPE_ZERO_MV   0x20000000
  76
  77 static const uint32_t ptype2mb_type[7] = {
  78                     MB_TYPE_INTRA,
  79                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  80                     MB_TYPE_L0,
  81                     MB_TYPE_L0 | MB_TYPE_CBP,
  82     MB_TYPE_QUANT | MB_TYPE_INTRA,
  83     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  84     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
  85 };
  86
  87 static const uint32_t btype2mb_type[11] = {
  88                     MB_TYPE_INTRA,
  89                     MB_TYPE_L1,
  90                     MB_TYPE_L1   | MB_TYPE_CBP,
  91                     MB_TYPE_L0,
  92                     MB_TYPE_L0   | MB_TYPE_CBP,
  93                     MB_TYPE_L0L1,
  94                     MB_TYPE_L0L1 | MB_TYPE_CBP,
  95     MB_TYPE_QUANT | MB_TYPE_INTRA,
  96     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
  97     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
  98     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
  99 };
 100
 101 /* as H.263, but only 17 codes */
 102 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 103 {
 104     int code, sign, val, shift;
 105
 106     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
 107     if (code == 0)
 108         return pred;
 109     if (code < 0)
 110         return 0xffff;
 111
 112     sign  = get_bits1(&s->gb);
 113     shift = fcode - 1;
 114     val   = code;
 115     if (shift) {
 116         val  = (val - 1) << shift;
 117         val |= get_bits(&s->gb, shift);
 118         val++;
 119     }
 120     if (sign)
 121         val = -val;
 122     val += pred;
 123
 124     /* modulo decoding */
 125     return sign_extend(val, 5 + shift);
 126 }
 127
 128 #define MAX_INDEX (64 - 1)
 129 #define check_scantable_index(ctx, x)                                         \
 130     do {                                                                      \
 131         if ((x) > MAX_INDEX) {                                                \
 132             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
 133                    ctx->mb_x, ctx->mb_y);                                     \
 134             return AVERROR_INVALIDDATA;                                       \
 135         }                                                                     \
 136     } while (0)
 137
 138 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 139                                            int16_t *block, int n)
 140 {
 141     int level, i, j, run;
 142     RLTable *rl                  = &ff_rl_mpeg1;
 143     uint8_t *const scantable     = s->intra_scantable.permutated;
 144     const uint16_t *quant_matrix = s->inter_matrix;
 145     const int qscale             = s->qscale;
 146
 147     {
 148         OPEN_READER(re, &s->gb);
 149         i = -1;
 150         // special case for first coefficient, no need to add second VLC table
 151         UPDATE_CACHE(re, &s->gb);
 152         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 153             level = (3 * qscale * quant_matrix[0]) >> 5;
 154             level = (level - 1) | 1;
 155             if (GET_CACHE(re, &s->gb) & 0x40000000)
 156                 level = -level;
 157             block[0] = level;
 158             i++;
 159             SKIP_BITS(re, &s->gb, 2);
 160             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 161                 goto end;
 162         }
 163         /* now quantify & encode AC coefficients */
 164         for (;;) {
 165             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 166                        TEX_VLC_BITS, 2, 0);
 167
 168             if (level != 0) {
 169                 i += run;
 170                 if (i > MAX_INDEX)
 171                     break;
 172                 j = scantable[i];
 173                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 174                 level = (level - 1) | 1;
 175                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 176                         SHOW_SBITS(re, &s->gb, 1);
 177                 SKIP_BITS(re, &s->gb, 1);
 178             } else {
 179                 /* escape */
 180                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 181                 LAST_SKIP_BITS(re, &s->gb, 6);
 182                 UPDATE_CACHE(re, &s->gb);
 183                 level = SHOW_SBITS(re, &s->gb, 8);
 184                 SKIP_BITS(re, &s->gb, 8);
 185                 if (level == -128) {
 186                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 187                     SKIP_BITS(re, &s->gb, 8);
 188                 } else if (level == 0) {
 189                     level = SHOW_UBITS(re, &s->gb, 8);
 190                     SKIP_BITS(re, &s->gb, 8);
 191                 }
 192                 i += run;
 193                 if (i > MAX_INDEX)
 194                     break;
 195                 j = scantable[i];
 196                 if (level < 0) {
 197                     level = -level;
 198                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 199                     level = (level - 1) | 1;
 200                     level = -level;
 201                 } else {
 202                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 203                     level = (level - 1) | 1;
 204                 }
 205             }
 206
 207             block[j] = level;
 208             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 209                 break;
 210             UPDATE_CACHE(re, &s->gb);
 211         }
 212 end:
 213         LAST_SKIP_BITS(re, &s->gb, 2);
 214         CLOSE_READER(re, &s->gb);
 215     }
 216
 217     check_scantable_index(s, i);
 218
 219     s->block_last_index[n] = i;
 220     return 0;
 221 }
 222
 223 /**
 224  * Note: this function can read out of range and crash for corrupt streams.
 225  * Changing this would eat up any speed benefits it has.
 226  * Do not use "fast" flag if you need the code to be robust.
 227  */
 228 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
 229                                                 int16_t *block, int n)
 230 {
 231     int level, i, j, run;
 232     RLTable *rl              = &ff_rl_mpeg1;
 233     uint8_t *const scantable = s->intra_scantable.permutated;
 234     const int qscale         = s->qscale;
 235
 236     {
 237         OPEN_READER(re, &s->gb);
 238         i = -1;
 239         // Special case for first coefficient, no need to add second VLC table.
 240         UPDATE_CACHE(re, &s->gb);
 241         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 242             level = (3 * qscale) >> 1;
 243             level = (level - 1) | 1;
 244             if (GET_CACHE(re, &s->gb) & 0x40000000)
 245                 level = -level;
 246             block[0] = level;
 247             i++;
 248             SKIP_BITS(re, &s->gb, 2);
 249             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 250                 goto end;
 251         }
 252
 253         /* now quantify & encode AC coefficients */
 254         for (;;) {
 255             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 256                        TEX_VLC_BITS, 2, 0);
 257
 258             if (level != 0) {
 259                 i += run;
 260                 if (i > MAX_INDEX)
 261                     break;
 262                 j = scantable[i];
 263                 level = ((level * 2 + 1) * qscale) >> 1;
 264                 level = (level - 1) | 1;
 265                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 266                         SHOW_SBITS(re, &s->gb, 1);
 267                 SKIP_BITS(re, &s->gb, 1);
 268             } else {
 269                 /* escape */
 270                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 271                 LAST_SKIP_BITS(re, &s->gb, 6);
 272                 UPDATE_CACHE(re, &s->gb);
 273                 level = SHOW_SBITS(re, &s->gb, 8);
 274                 SKIP_BITS(re, &s->gb, 8);
 275                 if (level == -128) {
 276                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 277                     SKIP_BITS(re, &s->gb, 8);
 278                 } else if (level == 0) {
 279                     level = SHOW_UBITS(re, &s->gb, 8);
 280                     SKIP_BITS(re, &s->gb, 8);
 281                 }
 282                 i += run;
 283                 if (i > MAX_INDEX)
 284                     break;
 285                 j = scantable[i];
 286                 if (level < 0) {
 287                     level = -level;
 288                     level = ((level * 2 + 1) * qscale) >> 1;
 289                     level = (level - 1) | 1;
 290                     level = -level;
 291                 } else {
 292                     level = ((level * 2 + 1) * qscale) >> 1;
 293                     level = (level - 1) | 1;
 294                 }
 295             }
 296
 297             block[j] = level;
 298             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 299                 break;
 300             UPDATE_CACHE(re, &s->gb);
 301         }
 302 end:
 303         LAST_SKIP_BITS(re, &s->gb, 2);
 304         CLOSE_READER(re, &s->gb);
 305     }
 306
 307     check_scantable_index(s, i);
 308
 309     s->block_last_index[n] = i;
 310     return 0;
 311 }
 312
 313 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 314                                                int16_t *block, int n)
 315 {
 316     int level, i, j, run;
 317     RLTable *rl = &ff_rl_mpeg1;
 318     uint8_t *const scantable = s->intra_scantable.permutated;
 319     const uint16_t *quant_matrix;
 320     const int qscale = s->qscale;
 321     int mismatch;
 322
 323     mismatch = 1;
 324
 325     {
 326         OPEN_READER(re, &s->gb);
 327         i = -1;
 328         if (n < 4)
 329             quant_matrix = s->inter_matrix;
 330         else
 331             quant_matrix = s->chroma_inter_matrix;
 332
 333         // Special case for first coefficient, no need to add second VLC table.
 334         UPDATE_CACHE(re, &s->gb);
 335         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 336             level = (3 * qscale * quant_matrix[0]) >> 5;
 337             if (GET_CACHE(re, &s->gb) & 0x40000000)
 338                 level = -level;
 339             block[0]  = level;
 340             mismatch ^= level;
 341             i++;
 342             SKIP_BITS(re, &s->gb, 2);
 343             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 344                 goto end;
 345         }
 346
 347         /* now quantify & encode AC coefficients */
 348         for (;;) {
 349             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 350                        TEX_VLC_BITS, 2, 0);
 351
 352             if (level != 0) {
 353                 i += run;
 354                 if (i > MAX_INDEX)
 355                     break;
 356                 j = scantable[i];
 357                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 358                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 359                         SHOW_SBITS(re, &s->gb, 1);
 360                 SKIP_BITS(re, &s->gb, 1);
 361             } else {
 362                 /* escape */
 363                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 364                 LAST_SKIP_BITS(re, &s->gb, 6);
 365                 UPDATE_CACHE(re, &s->gb);
 366                 level = SHOW_SBITS(re, &s->gb, 12);
 367                 SKIP_BITS(re, &s->gb, 12);
 368
 369                 i += run;
 370                 if (i > MAX_INDEX)
 371                     break;
 372                 j = scantable[i];
 373                 if (level < 0) {
 374                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 375                     level = -level;
 376                 } else {
 377                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 378                 }
 379             }
 380
 381             mismatch ^= level;
 382             block[j]  = level;
 383             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 384                 break;
 385             UPDATE_CACHE(re, &s->gb);
 386         }
 387 end:
 388         LAST_SKIP_BITS(re, &s->gb, 2);
 389         CLOSE_READER(re, &s->gb);
 390     }
 391     block[63] ^= (mismatch & 1);
 392
 393     check_scantable_index(s, i);
 394
 395     s->block_last_index[n] = i;
 396     return 0;
 397 }
 398
 399 /**
 400  * Note: this function can read out of range and crash for corrupt streams.
 401  * Changing this would eat up any speed benefits it has.
 402  * Do not use "fast" flag if you need the code to be robust.
 403  */
 404 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 405                                                     int16_t *block, int n)
 406 {
 407     int level, i, j, run;
 408     RLTable *rl              = &ff_rl_mpeg1;
 409     uint8_t *const scantable = s->intra_scantable.permutated;
 410     const int qscale         = s->qscale;
 411     OPEN_READER(re, &s->gb);
 412     i = -1;
 413
 414     // special case for first coefficient, no need to add second VLC table
 415     UPDATE_CACHE(re, &s->gb);
 416     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 417         level = (3 * qscale) >> 1;
 418         if (GET_CACHE(re, &s->gb) & 0x40000000)
 419             level = -level;
 420         block[0] = level;
 421         i++;
 422         SKIP_BITS(re, &s->gb, 2);
 423         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 424             goto end;
 425     }
 426
 427     /* now quantify & encode AC coefficients */
 428     for (;;) {
 429         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 430
 431         if (level != 0) {
 432             i += run;
 433             if (i > MAX_INDEX)
 434                 break;
 435             j = scantable[i];
 436             level = ((level * 2 + 1) * qscale) >> 1;
 437             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 438                     SHOW_SBITS(re, &s->gb, 1);
 439             SKIP_BITS(re, &s->gb, 1);
 440         } else {
 441             /* escape */
 442             run = SHOW_UBITS(re, &s->gb, 6) + 1;
 443             LAST_SKIP_BITS(re, &s->gb, 6);
 444             UPDATE_CACHE(re, &s->gb);
 445             level = SHOW_SBITS(re, &s->gb, 12);
 446             SKIP_BITS(re, &s->gb, 12);
 447
 448             i += run;
 449             if (i > MAX_INDEX)
 450                 break;
 451             j = scantable[i];
 452             if (level < 0) {
 453                 level = ((-level * 2 + 1) * qscale) >> 1;
 454                 level = -level;
 455             } else {
 456                 level = ((level * 2 + 1) * qscale) >> 1;
 457             }
 458         }
 459
 460         block[j] = level;
 461         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
 462             break;
 463
 464         UPDATE_CACHE(re, &s->gb);
 465     }
 466 end:
 467     LAST_SKIP_BITS(re, &s->gb, 2);
 468     CLOSE_READER(re, &s->gb);
 469
 470     check_scantable_index(s, i);
 471
 472     s->block_last_index[n] = i;
 473     return 0;
 474 }
 475
 476 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
 477                                            int16_t *block, int n)
 478 {
 479     int level, dc, diff, i, j, run;
 480     int component;
 481     RLTable *rl;
 482     uint8_t *const scantable = s->intra_scantable.permutated;
 483     const uint16_t *quant_matrix;
 484     const int qscale = s->qscale;
 485     int mismatch;
 486
 487     /* DC coefficient */
 488     if (n < 4) {
 489         quant_matrix = s->intra_matrix;
 490         component    = 0;
 491     } else {
 492         quant_matrix = s->chroma_intra_matrix;
 493         component    = (n & 1) + 1;
 494     }
 495     diff = decode_dc(&s->gb, component);
 496     if (diff >= 0xffff)
 497         return AVERROR_INVALIDDATA;
 498     dc  = s->last_dc[component];
 499     dc += diff;
 500     s->last_dc[component] = dc;
 501     block[0] = dc * (1 << (3 - s->intra_dc_precision));
 502     ff_tlog(s->avctx, "dc=%d\n", block[0]);
 503     mismatch = block[0] ^ 1;
 504     i = 0;
 505     if (s->intra_vlc_format)
 506         rl = &ff_rl_mpeg2;
 507     else
 508         rl = &ff_rl_mpeg1;
 509
 510     {
 511         OPEN_READER(re, &s->gb);
 512         /* now quantify & encode AC coefficients */
 513         for (;;) {
 514             UPDATE_CACHE(re, &s->gb);
 515             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 516                        TEX_VLC_BITS, 2, 0);
 517
 518             if (level == 127) {
 519                 break;
 520             } else if (level != 0) {
 521                 i += run;
 522                 if (i > MAX_INDEX)
 523                     break;
 524                 j = scantable[i];
 525                 level = (level * qscale * quant_matrix[j]) >> 4;
 526                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 527                         SHOW_SBITS(re, &s->gb, 1);
 528                 LAST_SKIP_BITS(re, &s->gb, 1);
 529             } else {
 530                 /* escape */
 531                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 532                 LAST_SKIP_BITS(re, &s->gb, 6);
 533                 UPDATE_CACHE(re, &s->gb);
 534                 level = SHOW_SBITS(re, &s->gb, 12);
 535                 SKIP_BITS(re, &s->gb, 12);
 536                 i += run;
 537                 if (i > MAX_INDEX)
 538                     break;
 539                 j = scantable[i];
 540                 if (level < 0) {
 541                     level = (-level * qscale * quant_matrix[j]) >> 4;
 542                     level = -level;
 543                 } else {
 544                     level = (level * qscale * quant_matrix[j]) >> 4;
 545                 }
 546             }
 547
 548             mismatch ^= level;
 549             block[j]  = level;
 550         }
 551         CLOSE_READER(re, &s->gb);
 552     }
 553     block[63] ^= mismatch & 1;
 554
 555     check_scantable_index(s, i);
 556
 557     s->block_last_index[n] = i;
 558     return 0;
 559 }
 560
 561 /**
 562  * Note: this function can read out of range and crash for corrupt streams.
 563  * Changing this would eat up any speed benefits it has.
 564  * Do not use "fast" flag if you need the code to be robust.
 565  */
 566 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
 567                                                 int16_t *block, int n)
 568 {
 569     int level, dc, diff, i, j, run;
 570     int component;
 571     RLTable *rl;
 572     uint8_t *const scantable = s->intra_scantable.permutated;
 573     const uint16_t *quant_matrix;
 574     const int qscale = s->qscale;
 575
 576     /* DC coefficient */
 577     if (n < 4) {
 578         quant_matrix = s->intra_matrix;
 579         component    = 0;
 580     } else {
 581         quant_matrix = s->chroma_intra_matrix;
 582         component    = (n & 1) + 1;
 583     }
 584     diff = decode_dc(&s->gb, component);
 585     if (diff >= 0xffff)
 586         return AVERROR_INVALIDDATA;
 587     dc = s->last_dc[component];
 588     dc += diff;
 589     s->last_dc[component] = dc;
 590     block[0] = dc * (1 << (3 - s->intra_dc_precision));
 591     i = 0;
 592     if (s->intra_vlc_format)
 593         rl = &ff_rl_mpeg2;
 594     else
 595         rl = &ff_rl_mpeg1;
 596
 597     {
 598         OPEN_READER(re, &s->gb);
 599         /* now quantify & encode AC coefficients */
 600         for (;;) {
 601             UPDATE_CACHE(re, &s->gb);
 602             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 603                        TEX_VLC_BITS, 2, 0);
 604
 605             if (level >= 64 || i > 63) {
 606                 break;
 607             } else if (level != 0) {
 608                 i += run;
 609                 j = scantable[i];
 610                 level = (level * qscale * quant_matrix[j]) >> 4;
 611                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 612                         SHOW_SBITS(re, &s->gb, 1);
 613                 LAST_SKIP_BITS(re, &s->gb, 1);
 614             } else {
 615                 /* escape */
 616                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 617                 LAST_SKIP_BITS(re, &s->gb, 6);
 618                 UPDATE_CACHE(re, &s->gb);
 619                 level = SHOW_SBITS(re, &s->gb, 12);
 620                 SKIP_BITS(re, &s->gb, 12);
 621                 i += run;
 622                 j = scantable[i];
 623                 if (level < 0) {
 624                     level = (-level * qscale * quant_matrix[j]) >> 4;
 625                     level = -level;
 626                 } else {
 627                     level = (level * qscale * quant_matrix[j]) >> 4;
 628                 }
 629             }
 630
 631             block[j] = level;
 632         }
 633         CLOSE_READER(re, &s->gb);
 634     }
 635
 636     check_scantable_index(s, i);
 637
 638     s->block_last_index[n] = i;
 639     return 0;
 640 }
 641
 642 /******************************************/
 643 /* decoding */
 644
 645 static inline int get_dmv(MpegEncContext *s)
 646 {
 647     if (get_bits1(&s->gb))
 648         return 1 - (get_bits1(&s->gb) << 1);
 649     else
 650         return 0;
 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_tlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 666
 667     av_assert2(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                 av_log(s->avctx, AV_LOG_ERROR, "skip with previntra\n");
 684                 return AVERROR_INVALIDDATA;
 685             }
 686             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 687                 mb_type | MB_TYPE_SKIP;
 688
 689             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 690                 s->mb_skipped = 1;
 691         }
 692
 693         return 0;
 694     }
 695
 696     switch (s->pict_type) {
 697     default:
 698     case AV_PICTURE_TYPE_I:
 699         if (get_bits1(&s->gb) == 0) {
 700             if (get_bits1(&s->gb) == 0) {
 701                 av_log(s->avctx, AV_LOG_ERROR,
 702                        "Invalid mb type in I-frame at %d %d\n",
 703                        s->mb_x, s->mb_y);
 704                 return AVERROR_INVALIDDATA;
 705             }
 706             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 707         } else {
 708             mb_type = MB_TYPE_INTRA;
 709         }
 710         break;
 711     case AV_PICTURE_TYPE_P:
 712         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 713         if (mb_type < 0) {
 714             av_log(s->avctx, AV_LOG_ERROR,
 715                    "Invalid mb type in P-frame at %d %d\n", s->mb_x, s->mb_y);
 716             return AVERROR_INVALIDDATA;
 717         }
 718         mb_type = ptype2mb_type[mb_type];
 719         break;
 720     case AV_PICTURE_TYPE_B:
 721         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 722         if (mb_type < 0) {
 723             av_log(s->avctx, AV_LOG_ERROR,
 724                    "Invalid mb type in B-frame at %d %d\n", s->mb_x, s->mb_y);
 725             return AVERROR_INVALIDDATA;
 726         }
 727         mb_type = btype2mb_type[mb_type];
 728         break;
 729     }
 730     ff_tlog(s->avctx, "mb_type=%x\n", mb_type);
 731 //    motion_type = 0; /* avoid warning */
 732     if (IS_INTRA(mb_type)) {
 733         s->bdsp.clear_blocks(s->block[0]);
 734
 735         if (!s->chroma_y_shift)
 736             s->bdsp.clear_blocks(s->block[6]);
 737
 738         /* compute DCT type */
 739         // FIXME: add an interlaced_dct coded var?
 740         if (s->picture_structure == PICT_FRAME &&
 741             !s->frame_pred_frame_dct)
 742             s->interlaced_dct = get_bits1(&s->gb);
 743
 744         if (IS_QUANT(mb_type))
 745             s->qscale = mpeg_get_qscale(s);
 746
 747         if (s->concealment_motion_vectors) {
 748             /* just parse them */
 749             if (s->picture_structure != PICT_FRAME)
 750                 skip_bits1(&s->gb);  /* field select */
 751
 752             s->mv[0][0][0]      =
 753             s->last_mv[0][0][0] =
 754             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
 755                                                      s->last_mv[0][0][0]);
 756             s->mv[0][0][1]      =
 757             s->last_mv[0][0][1] =
 758             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
 759                                                      s->last_mv[0][0][1]);
 760
 761             check_marker(s->avctx, &s->gb, "after concealment_motion_vectors");
 762         } else {
 763             /* reset mv prediction */
 764             memset(s->last_mv, 0, sizeof(s->last_mv));
 765         }
 766         s->mb_intra = 1;
 767         // if 1, we memcpy blocks in xvmcvideo
 768         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
 769             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 770
 771         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 772             if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
 773                 for (i = 0; i < 6; i++)
 774                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 775             } else {
 776                 for (i = 0; i < mb_block_count; i++)
 777                     if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 778                         return ret;
 779             }
 780         } else {
 781             for (i = 0; i < 6; i++) {
 782                 ret = ff_mpeg1_decode_block_intra(&s->gb,
 783                                                   s->intra_matrix,
 784                                                   s->intra_scantable.permutated,
 785                                                   s->last_dc, *s->pblocks[i],
 786                                                   i, s->qscale);
 787                 if (ret < 0) {
 788                     av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",
 789                            s->mb_x, s->mb_y);
 790                     return ret;
 791                 }
 792
 793                 s->block_last_index[i] = ret;
 794             }
 795         }
 796     } else {
 797         if (mb_type & MB_TYPE_ZERO_MV) {
 798             av_assert2(mb_type & MB_TYPE_CBP);
 799
 800             s->mv_dir = MV_DIR_FORWARD;
 801             if (s->picture_structure == PICT_FRAME) {
 802                 if (s->picture_structure == PICT_FRAME
 803                     && !s->frame_pred_frame_dct)
 804                     s->interlaced_dct = get_bits1(&s->gb);
 805                 s->mv_type = MV_TYPE_16X16;
 806             } else {
 807                 s->mv_type            = MV_TYPE_FIELD;
 808                 mb_type              |= MB_TYPE_INTERLACED;
 809                 s->field_select[0][0] = s->picture_structure - 1;
 810             }
 811
 812             if (IS_QUANT(mb_type))
 813                 s->qscale = mpeg_get_qscale(s);
 814
 815             s->last_mv[0][0][0] = 0;
 816             s->last_mv[0][0][1] = 0;
 817             s->last_mv[0][1][0] = 0;
 818             s->last_mv[0][1][1] = 0;
 819             s->mv[0][0][0]      = 0;
 820             s->mv[0][0][1]      = 0;
 821         } else {
 822             av_assert2(mb_type & MB_TYPE_L0L1);
 823             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 824             /* get additional motion vector type */
 825             if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) {
 826                 motion_type = MT_FRAME;
 827             } else {
 828                 motion_type = get_bits(&s->gb, 2);
 829                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 830                     s->interlaced_dct = get_bits1(&s->gb);
 831             }
 832
 833             if (IS_QUANT(mb_type))
 834                 s->qscale = mpeg_get_qscale(s);
 835
 836             /* motion vectors */
 837             s->mv_dir = (mb_type >> 13) & 3;
 838             ff_tlog(s->avctx, "motion_type=%d\n", motion_type);
 839             switch (motion_type) {
 840             case MT_FRAME: /* or MT_16X8 */
 841                 if (s->picture_structure == PICT_FRAME) {
 842                     mb_type   |= MB_TYPE_16x16;
 843                     s->mv_type = MV_TYPE_16X16;
 844                     for (i = 0; i < 2; i++) {
 845                         if (USES_LIST(mb_type, i)) {
 846                             /* MT_FRAME */
 847                             s->mv[i][0][0]      =
 848                             s->last_mv[i][0][0] =
 849                             s->last_mv[i][1][0] =
 850                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 851                                                    s->last_mv[i][0][0]);
 852                             s->mv[i][0][1]      =
 853                             s->last_mv[i][0][1] =
 854                             s->last_mv[i][1][1] =
 855                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 856                                                    s->last_mv[i][0][1]);
 857                             /* full_pel: only for MPEG-1 */
 858                             if (s->full_pel[i]) {
 859                                 s->mv[i][0][0] *= 2;
 860                                 s->mv[i][0][1] *= 2;
 861                             }
 862                         }
 863                     }
 864                 } else {
 865                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 866                     s->mv_type = MV_TYPE_16X8;
 867                     for (i = 0; i < 2; i++) {
 868                         if (USES_LIST(mb_type, i)) {
 869                             /* MT_16X8 */
 870                             for (j = 0; j < 2; j++) {
 871                                 s->field_select[i][j] = get_bits1(&s->gb);
 872                                 for (k = 0; k < 2; k++) {
 873                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 874                                                              s->last_mv[i][j][k]);
 875                                     s->last_mv[i][j][k] = val;
 876                                     s->mv[i][j][k]      = val;
 877                                 }
 878                             }
 879                         }
 880                     }
 881                 }
 882                 break;
 883             case MT_FIELD:
 884                 s->mv_type = MV_TYPE_FIELD;
 885                 if (s->picture_structure == PICT_FRAME) {
 886                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 887                     for (i = 0; i < 2; i++) {
 888                         if (USES_LIST(mb_type, i)) {
 889                             for (j = 0; j < 2; j++) {
 890                                 s->field_select[i][j] = get_bits1(&s->gb);
 891                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 892                                                          s->last_mv[i][j][0]);
 893                                 s->last_mv[i][j][0] = val;
 894                                 s->mv[i][j][0]      = val;
 895                                 ff_tlog(s->avctx, "fmx=%d\n", val);
 896                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 897                                                          s->last_mv[i][j][1] >> 1);
 898                                 s->last_mv[i][j][1] = 2 * val;
 899                                 s->mv[i][j][1]      = val;
 900                                 ff_tlog(s->avctx, "fmy=%d\n", val);
 901                             }
 902                         }
 903                     }
 904                 } else {
 905                     av_assert0(!s->progressive_sequence);
 906                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 907                     for (i = 0; i < 2; i++) {
 908                         if (USES_LIST(mb_type, i)) {
 909                             s->field_select[i][0] = get_bits1(&s->gb);
 910                             for (k = 0; k < 2; k++) {
 911                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 912                                                          s->last_mv[i][0][k]);
 913                                 s->last_mv[i][0][k] = val;
 914                                 s->last_mv[i][1][k] = val;
 915                                 s->mv[i][0][k]      = val;
 916                             }
 917                         }
 918                     }
 919                 }
 920                 break;
 921             case MT_DMV:
 922                 if (s->progressive_sequence){
 923                     av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
 924                     return AVERROR_INVALIDDATA;
 925                 }
 926                 s->mv_type = MV_TYPE_DMV;
 927                 for (i = 0; i < 2; i++) {
 928                     if (USES_LIST(mb_type, i)) {
 929                         int dmx, dmy, mx, my, m;
 930                         const int my_shift = s->picture_structure == PICT_FRAME;
 931
 932                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 933                                                 s->last_mv[i][0][0]);
 934                         s->last_mv[i][0][0] = mx;
 935                         s->last_mv[i][1][0] = mx;
 936                         dmx = get_dmv(s);
 937                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 938                                                  s->last_mv[i][0][1] >> my_shift);
 939                         dmy = get_dmv(s);
 940
 941
 942                         s->last_mv[i][0][1] = my * (1 << my_shift);
 943                         s->last_mv[i][1][1] = my * (1 << my_shift);
 944
 945                         s->mv[i][0][0] = mx;
 946                         s->mv[i][0][1] = my;
 947                         s->mv[i][1][0] = mx; // not used
 948                         s->mv[i][1][1] = my; // not used
 949
 950                         if (s->picture_structure == PICT_FRAME) {
 951                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 952
 953                             // m = 1 + 2 * s->top_field_first;
 954                             m = s->top_field_first ? 1 : 3;
 955
 956                             /* top -> top pred */
 957                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 958                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 959                             m = 4 - m;
 960                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 961                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 962                         } else {
 963                             mb_type |= MB_TYPE_16x16;
 964
 965                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 966                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 967                             if (s->picture_structure == PICT_TOP_FIELD)
 968                                 s->mv[i][2][1]--;
 969                             else
 970                                 s->mv[i][2][1]++;
 971                         }
 972                     }
 973                 }
 974                 break;
 975             default:
 976                 av_log(s->avctx, AV_LOG_ERROR,
 977                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 978                 return AVERROR_INVALIDDATA;
 979             }
 980         }
 981
 982         s->mb_intra = 0;
 983         if (HAS_CBP(mb_type)) {
 984             s->bdsp.clear_blocks(s->block[0]);
 985
 986             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 987             if (mb_block_count > 6) {
 988                 cbp *= 1 << mb_block_count - 6;
 989                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
 990                 s->bdsp.clear_blocks(s->block[6]);
 991             }
 992             if (cbp <= 0) {
 993                 av_log(s->avctx, AV_LOG_ERROR,
 994                        "invalid cbp %d at %d %d\n", cbp, s->mb_x, s->mb_y);
 995                 return AVERROR_INVALIDDATA;
 996             }
 997
 998             // if 1, we memcpy blocks in xvmcvideo
 999             if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1000                 ff_xvmc_pack_pblocks(s, cbp);
1001
1002             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1003                 if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1004                     for (i = 0; i < 6; i++) {
1005                         if (cbp & 32)
1006                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1007                         else
1008                             s->block_last_index[i] = -1;
1009                         cbp += cbp;
1010                     }
1011                 } else {
1012                     cbp <<= 12 - mb_block_count;
1013
1014                     for (i = 0; i < mb_block_count; i++) {
1015                         if (cbp & (1 << 11)) {
1016                             if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
1017                                 return ret;
1018                         } else {
1019                             s->block_last_index[i] = -1;
1020                         }
1021                         cbp += cbp;
1022                     }
1023                 }
1024             } else {
1025                 if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1026                     for (i = 0; i < 6; i++) {
1027                         if (cbp & 32)
1028                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1029                         else
1030                             s->block_last_index[i] = -1;
1031                         cbp += cbp;
1032                     }
1033                 } else {
1034                     for (i = 0; i < 6; i++) {
1035                         if (cbp & 32) {
1036                             if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
1037                                 return ret;
1038                         } else {
1039                             s->block_last_index[i] = -1;
1040                         }
1041                         cbp += cbp;
1042                     }
1043                 }
1044             }
1045         } else {
1046             for (i = 0; i < 12; i++)
1047                 s->block_last_index[i] = -1;
1048         }
1049     }
1050
1051     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1052
1053     return 0;
1054 }
1055
1056 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1057 {
1058     Mpeg1Context *s    = avctx->priv_data;
1059     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1060
1061     ff_mpv_decode_defaults(s2);
1062
1063     if (   avctx->codec_tag != AV_RL32("VCR2")
1064         && avctx->codec_tag != AV_RL32("BW10"))
1065         avctx->coded_width = avctx->coded_height = 0; // do not trust dimensions from input
1066     ff_mpv_decode_init(s2, avctx);
1067
1068     s->mpeg_enc_ctx.avctx  = avctx;
1069
1070     /* we need some permutation to store matrices,
1071      * until the decoder sets the real permutation. */
1072     ff_mpv_idct_init(s2);
1073     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1074     ff_mpeg12_init_vlcs();
1075
1076     s2->chroma_format              = 1;
1077     s->mpeg_enc_ctx_allocated      = 0;
1078     s->mpeg_enc_ctx.picture_number = 0;
1079     s->repeat_field                = 0;
1080     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1081     avctx->color_range             = AVCOL_RANGE_MPEG;
1082     return 0;
1083 }
1084
1085 #if HAVE_THREADS
1086 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1087                                              const AVCodecContext *avctx_from)
1088 {
1089     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1090     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1091     int err;
1092
1093     if (avctx == avctx_from               ||
1094         !ctx_from->mpeg_enc_ctx_allocated ||
1095         !s1->context_initialized)
1096         return 0;
1097
1098     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1099     if (err)
1100         return err;
1101
1102     if (!ctx->mpeg_enc_ctx_allocated)
1103         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1104
1105     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1106         s->picture_number++;
1107
1108     return 0;
1109 }
1110 #endif
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 static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1125 #if CONFIG_MPEG1_NVDEC_HWACCEL
1126     AV_PIX_FMT_CUDA,
1127 #endif
1128 #if CONFIG_MPEG1_XVMC_HWACCEL
1129     AV_PIX_FMT_XVMC,
1130 #endif
1131 #if CONFIG_MPEG1_VDPAU_HWACCEL
1132     AV_PIX_FMT_VDPAU,
1133 #endif
1134     AV_PIX_FMT_YUV420P,
1135     AV_PIX_FMT_NONE
1136 };
1137
1138 static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1139 #if CONFIG_MPEG2_NVDEC_HWACCEL
1140     AV_PIX_FMT_CUDA,
1141 #endif
1142 #if CONFIG_MPEG2_XVMC_HWACCEL
1143     AV_PIX_FMT_XVMC,
1144 #endif
1145 #if CONFIG_MPEG2_VDPAU_HWACCEL
1146     AV_PIX_FMT_VDPAU,
1147 #endif
1148 #if CONFIG_MPEG2_DXVA2_HWACCEL
1149     AV_PIX_FMT_DXVA2_VLD,
1150 #endif
1151 #if CONFIG_MPEG2_D3D11VA_HWACCEL
1152     AV_PIX_FMT_D3D11VA_VLD,
1153     AV_PIX_FMT_D3D11,
1154 #endif
1155 #if CONFIG_MPEG2_VAAPI_HWACCEL
1156     AV_PIX_FMT_VAAPI,
1157 #endif
1158 #if CONFIG_MPEG2_VIDEOTOOLBOX_HWACCEL
1159     AV_PIX_FMT_VIDEOTOOLBOX,
1160 #endif
1161     AV_PIX_FMT_YUV420P,
1162     AV_PIX_FMT_NONE
1163 };
1164
1165 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1166     AV_PIX_FMT_YUV422P,
1167     AV_PIX_FMT_NONE
1168 };
1169
1170 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1171     AV_PIX_FMT_YUV444P,
1172     AV_PIX_FMT_NONE
1173 };
1174
1175 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1176 {
1177     Mpeg1Context *s1  = avctx->priv_data;
1178     MpegEncContext *s = &s1->mpeg_enc_ctx;
1179     const enum AVPixelFormat *pix_fmts;
1180
1181     if (CONFIG_GRAY && (avctx->flags & AV_CODEC_FLAG_GRAY))
1182         return AV_PIX_FMT_GRAY8;
1183
1184     if (s->chroma_format < 2)
1185         pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1186                                 mpeg1_hwaccel_pixfmt_list_420 :
1187                                 mpeg2_hwaccel_pixfmt_list_420;
1188     else if (s->chroma_format == 2)
1189         pix_fmts = mpeg12_pixfmt_list_422;
1190     else
1191         pix_fmts = mpeg12_pixfmt_list_444;
1192
1193     return ff_thread_get_format(avctx, pix_fmts);
1194 }
1195
1196 static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
1197 {
1198     // until then pix_fmt may be changed right after codec init
1199     if (avctx->hwaccel)
1200         if (avctx->idct_algo == FF_IDCT_AUTO)
1201             avctx->idct_algo = FF_IDCT_NONE;
1202
1203     if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
1204         Mpeg1Context *s1 = avctx->priv_data;
1205         MpegEncContext *s = &s1->mpeg_enc_ctx;
1206
1207         s->pack_pblocks = 1;
1208     }
1209 }
1210
1211 /* Call this function when we know all parameters.
1212  * It may be called in different places for MPEG-1 and MPEG-2. */
1213 static int mpeg_decode_postinit(AVCodecContext *avctx)
1214 {
1215     Mpeg1Context *s1  = avctx->priv_data;
1216     MpegEncContext *s = &s1->mpeg_enc_ctx;
1217     uint8_t old_permutation[64];
1218     int ret;
1219
1220     if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1221         // MPEG-1 aspect
1222         AVRational aspect_inv = av_d2q(ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1223         avctx->sample_aspect_ratio = (AVRational) { aspect_inv.den, aspect_inv.num };
1224     } else { // MPEG-2
1225         // MPEG-2 aspect
1226         if (s->aspect_ratio_info > 1) {
1227             AVRational dar =
1228                 av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1229                                   (AVRational) { s1->pan_scan.width,
1230                                                  s1->pan_scan.height }),
1231                          (AVRational) { s->width, s->height });
1232
1233             /* We ignore the spec here and guess a bit as reality does not
1234              * match the spec, see for example res_change_ffmpeg_aspect.ts
1235              * and sequence-display-aspect.mpg.
1236              * issue1613, 621, 562 */
1237             if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1238                 (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1239                  av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1240                 s->avctx->sample_aspect_ratio =
1241                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1242                              (AVRational) { s->width, s->height });
1243             } else {
1244                 s->avctx->sample_aspect_ratio =
1245                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1246                              (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1247 // issue1613 4/3 16/9 -> 16/9
1248 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1249 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1250 //                s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1251                 ff_dlog(avctx, "aspect A %d/%d\n",
1252                         ff_mpeg2_aspect[s->aspect_ratio_info].num,
1253                         ff_mpeg2_aspect[s->aspect_ratio_info].den);
1254                 ff_dlog(avctx, "aspect B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1255                         s->avctx->sample_aspect_ratio.den);
1256             }
1257         } else {
1258             s->avctx->sample_aspect_ratio =
1259                 ff_mpeg2_aspect[s->aspect_ratio_info];
1260         }
1261     } // MPEG-2
1262
1263     if (av_image_check_sar(s->width, s->height,
1264                            avctx->sample_aspect_ratio) < 0) {
1265         av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
1266                 avctx->sample_aspect_ratio.num,
1267                 avctx->sample_aspect_ratio.den);
1268         avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
1269     }
1270
1271     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1272         avctx->coded_width       != s->width                ||
1273         avctx->coded_height      != s->height               ||
1274         s1->save_width           != s->width                ||
1275         s1->save_height          != s->height               ||
1276         av_cmp_q(s1->save_aspect, s->avctx->sample_aspect_ratio) ||
1277         (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1278         0) {
1279         if (s1->mpeg_enc_ctx_allocated) {
1280             ParseContext pc = s->parse_context;
1281             s->parse_context.buffer = 0;
1282             ff_mpv_common_end(s);
1283             s->parse_context = pc;
1284             s1->mpeg_enc_ctx_allocated = 0;
1285         }
1286
1287         ret = ff_set_dimensions(avctx, s->width, s->height);
1288         if (ret < 0)
1289             return ret;
1290
1291         if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
1292             avctx->rc_max_rate = s->bit_rate;
1293         } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
1294                    (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
1295             avctx->bit_rate = s->bit_rate;
1296         }
1297         s1->save_aspect          = s->avctx->sample_aspect_ratio;
1298         s1->save_width           = s->width;
1299         s1->save_height          = s->height;
1300         s1->save_progressive_seq = s->progressive_sequence;
1301
1302         /* low_delay may be forced, in this case we will have B-frames
1303          * that behave like P-frames. */
1304         avctx->has_b_frames = !s->low_delay;
1305
1306         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1307             // MPEG-1 fps
1308             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1309             avctx->ticks_per_frame     = 1;
1310
1311             avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1312         } else { // MPEG-2
1313             // MPEG-2 fps
1314             av_reduce(&s->avctx->framerate.num,
1315                       &s->avctx->framerate.den,
1316                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1317                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1318                       1 << 30);
1319             avctx->ticks_per_frame = 2;
1320
1321             switch (s->chroma_format) {
1322             case 1: avctx->chroma_sample_location = AVCHROMA_LOC_LEFT; break;
1323             case 2:
1324             case 3: avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT; break;
1325             default: av_assert0(0);
1326             }
1327         } // MPEG-2
1328
1329         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1330         setup_hwaccel_for_pixfmt(avctx);
1331
1332         /* Quantization matrices may need reordering
1333          * if DCT permutation is changed. */
1334         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1335
1336         ff_mpv_idct_init(s);
1337         if ((ret = ff_mpv_common_init(s)) < 0)
1338             return ret;
1339
1340         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1341         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1342         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1343         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1344
1345         s1->mpeg_enc_ctx_allocated = 1;
1346     }
1347     return 0;
1348 }
1349
1350 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1351                                 int buf_size)
1352 {
1353     Mpeg1Context *s1  = avctx->priv_data;
1354     MpegEncContext *s = &s1->mpeg_enc_ctx;
1355     int ref, f_code, vbv_delay;
1356
1357     init_get_bits(&s->gb, buf, buf_size * 8);
1358
1359     ref = get_bits(&s->gb, 10); /* temporal ref */
1360     s->pict_type = get_bits(&s->gb, 3);
1361     if (s->pict_type == 0 || s->pict_type > 3)
1362         return AVERROR_INVALIDDATA;
1363
1364     vbv_delay = get_bits(&s->gb, 16);
1365     s->vbv_delay = vbv_delay;
1366     if (s->pict_type == AV_PICTURE_TYPE_P ||
1367         s->pict_type == AV_PICTURE_TYPE_B) {
1368         s->full_pel[0] = get_bits1(&s->gb);
1369         f_code = get_bits(&s->gb, 3);
1370         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1371             return AVERROR_INVALIDDATA;
1372         f_code += !f_code;
1373         s->mpeg_f_code[0][0] = f_code;
1374         s->mpeg_f_code[0][1] = f_code;
1375     }
1376     if (s->pict_type == AV_PICTURE_TYPE_B) {
1377         s->full_pel[1] = get_bits1(&s->gb);
1378         f_code = get_bits(&s->gb, 3);
1379         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1380             return AVERROR_INVALIDDATA;
1381         f_code += !f_code;
1382         s->mpeg_f_code[1][0] = f_code;
1383         s->mpeg_f_code[1][1] = f_code;
1384     }
1385     s->current_picture.f->pict_type = s->pict_type;
1386     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1387
1388     if (avctx->debug & FF_DEBUG_PICT_INFO)
1389         av_log(avctx, AV_LOG_DEBUG,
1390                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1391
1392     s->y_dc_scale = 8;
1393     s->c_dc_scale = 8;
1394     return 0;
1395 }
1396
1397 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1398 {
1399     MpegEncContext *s = &s1->mpeg_enc_ctx;
1400     int horiz_size_ext, vert_size_ext;
1401     int bit_rate_ext;
1402     AVCPBProperties *cpb_props;
1403
1404     skip_bits(&s->gb, 1); /* profile and level esc*/
1405     s->avctx->profile       = get_bits(&s->gb, 3);
1406     s->avctx->level         = get_bits(&s->gb, 4);
1407     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1408     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1409
1410     if (!s->chroma_format) {
1411         s->chroma_format = 1;
1412         av_log(s->avctx, AV_LOG_WARNING, "Chroma format invalid\n");
1413     }
1414
1415     horiz_size_ext          = get_bits(&s->gb, 2);
1416     vert_size_ext           = get_bits(&s->gb, 2);
1417     s->width  |= (horiz_size_ext << 12);
1418     s->height |= (vert_size_ext  << 12);
1419     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1420     s->bit_rate += (bit_rate_ext << 18) * 400LL;
1421     check_marker(s->avctx, &s->gb, "after bit rate extension");
1422     s1->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1423
1424     s->low_delay = get_bits1(&s->gb);
1425     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
1426         s->low_delay = 1;
1427
1428     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1429     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1430
1431     ff_dlog(s->avctx, "sequence extension\n");
1432     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1433
1434     if (cpb_props = ff_add_cpb_side_data(s->avctx)) {
1435         cpb_props->buffer_size = s1->rc_buffer_size;
1436         if (s->bit_rate != 0x3FFFF*400)
1437             cpb_props->max_bitrate = s->bit_rate;
1438     }
1439
1440     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1441         av_log(s->avctx, AV_LOG_DEBUG,
1442                "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%"PRId64"\n",
1443                s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1444                s1->rc_buffer_size, s->bit_rate);
1445 }
1446
1447 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1448 {
1449     MpegEncContext *s = &s1->mpeg_enc_ctx;
1450     int color_description, w, h;
1451
1452     skip_bits(&s->gb, 3); /* video format */
1453     color_description = get_bits1(&s->gb);
1454     if (color_description) {
1455         s->avctx->color_primaries = get_bits(&s->gb, 8);
1456         s->avctx->color_trc       = get_bits(&s->gb, 8);
1457         s->avctx->colorspace      = get_bits(&s->gb, 8);
1458     }
1459     w = get_bits(&s->gb, 14);
1460     skip_bits(&s->gb, 1); // marker
1461     h = get_bits(&s->gb, 14);
1462     // remaining 3 bits are zero padding
1463
1464     s1->pan_scan.width  = 16 * w;
1465     s1->pan_scan.height = 16 * h;
1466
1467     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1468         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1469 }
1470
1471 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1472 {
1473     MpegEncContext *s = &s1->mpeg_enc_ctx;
1474     int i, nofco;
1475
1476     nofco = 1;
1477     if (s->progressive_sequence) {
1478         if (s->repeat_first_field) {
1479             nofco++;
1480             if (s->top_field_first)
1481                 nofco++;
1482         }
1483     } else {
1484         if (s->picture_structure == PICT_FRAME) {
1485             nofco++;
1486             if (s->repeat_first_field)
1487                 nofco++;
1488         }
1489     }
1490     for (i = 0; i < nofco; i++) {
1491         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1492         skip_bits(&s->gb, 1); // marker
1493         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1494         skip_bits(&s->gb, 1); // marker
1495     }
1496
1497     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1498         av_log(s->avctx, AV_LOG_DEBUG,
1499                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1500                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1501                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1502                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1503 }
1504
1505 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1506                        uint16_t matrix1[64], int intra)
1507 {
1508     int i;
1509
1510     for (i = 0; i < 64; i++) {
1511         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1512         int v = get_bits(&s->gb, 8);
1513         if (v == 0) {
1514             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1515             return AVERROR_INVALIDDATA;
1516         }
1517         if (intra && i == 0 && v != 8) {
1518             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1519             v = 8; // needed by pink.mpg / issue1046
1520         }
1521         matrix0[j] = v;
1522         if (matrix1)
1523             matrix1[j] = v;
1524     }
1525     return 0;
1526 }
1527
1528 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1529 {
1530     ff_dlog(s->avctx, "matrix extension\n");
1531
1532     if (get_bits1(&s->gb))
1533         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1534     if (get_bits1(&s->gb))
1535         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1536     if (get_bits1(&s->gb))
1537         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1538     if (get_bits1(&s->gb))
1539         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1540 }
1541
1542 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1543 {
1544     MpegEncContext *s = &s1->mpeg_enc_ctx;
1545
1546     s->full_pel[0]       = s->full_pel[1] = 0;
1547     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1548     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1549     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1550     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1551     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1552         av_log(s->avctx, AV_LOG_ERROR,
1553                "Missing picture start code, guessing missing values\n");
1554         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1555             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1556                 s->pict_type = AV_PICTURE_TYPE_I;
1557             else
1558                 s->pict_type = AV_PICTURE_TYPE_P;
1559         } else
1560             s->pict_type = AV_PICTURE_TYPE_B;
1561         s->current_picture.f->pict_type = s->pict_type;
1562         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1563     }
1564     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1565     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1566     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1567     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1568
1569     s->intra_dc_precision         = get_bits(&s->gb, 2);
1570     s->picture_structure          = get_bits(&s->gb, 2);
1571     s->top_field_first            = get_bits1(&s->gb);
1572     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1573     s->concealment_motion_vectors = get_bits1(&s->gb);
1574     s->q_scale_type               = get_bits1(&s->gb);
1575     s->intra_vlc_format           = get_bits1(&s->gb);
1576     s->alternate_scan             = get_bits1(&s->gb);
1577     s->repeat_first_field         = get_bits1(&s->gb);
1578     s->chroma_420_type            = get_bits1(&s->gb);
1579     s->progressive_frame          = get_bits1(&s->gb);
1580
1581     if (s->alternate_scan) {
1582         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1583         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1584     } else {
1585         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1586         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1587     }
1588
1589     /* composite display not parsed */
1590     ff_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1591     ff_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1592     ff_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1593     ff_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1594     ff_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1595     ff_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1596     ff_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1597     ff_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1598     ff_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1599 }
1600
1601 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1602 {
1603     AVCodecContext *avctx = s->avctx;
1604     Mpeg1Context *s1      = (Mpeg1Context *) s;
1605     int ret;
1606
1607     if (!(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS)) {
1608         if (s->mb_width * s->mb_height * 11LL / (33 * 2 * 8) > buf_size)
1609             return AVERROR_INVALIDDATA;
1610     }
1611
1612     /* start frame decoding */
1613     if (s->first_field || s->picture_structure == PICT_FRAME) {
1614         AVFrameSideData *pan_scan;
1615
1616         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1617             return ret;
1618
1619         ff_mpeg_er_frame_start(s);
1620
1621         /* first check if we must repeat the frame */
1622         s->current_picture_ptr->f->repeat_pict = 0;
1623         if (s->repeat_first_field) {
1624             if (s->progressive_sequence) {
1625                 if (s->top_field_first)
1626                     s->current_picture_ptr->f->repeat_pict = 4;
1627                 else
1628                     s->current_picture_ptr->f->repeat_pict = 2;
1629             } else if (s->progressive_frame) {
1630                 s->current_picture_ptr->f->repeat_pict = 1;
1631             }
1632         }
1633
1634         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1635                                           AV_FRAME_DATA_PANSCAN,
1636                                           sizeof(s1->pan_scan));
1637         if (!pan_scan)
1638             return AVERROR(ENOMEM);
1639         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1640
1641         if (s1->a53_caption) {
1642             AVFrameSideData *sd = av_frame_new_side_data(
1643                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1644                 s1->a53_caption_size);
1645             if (sd)
1646                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1647             av_freep(&s1->a53_caption);
1648         }
1649
1650         if (s1->has_stereo3d) {
1651             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1652             if (!stereo)
1653                 return AVERROR(ENOMEM);
1654
1655             *stereo = s1->stereo3d;
1656             s1->has_stereo3d = 0;
1657         }
1658
1659         if (s1->has_afd) {
1660             AVFrameSideData *sd =
1661                 av_frame_new_side_data(s->current_picture_ptr->f,
1662                                        AV_FRAME_DATA_AFD, 1);
1663             if (!sd)
1664                 return AVERROR(ENOMEM);
1665
1666             *sd->data   = s1->afd;
1667             s1->has_afd = 0;
1668         }
1669
1670         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1671             ff_thread_finish_setup(avctx);
1672     } else { // second field
1673         int i;
1674
1675         if (!s->current_picture_ptr) {
1676             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1677             return AVERROR_INVALIDDATA;
1678         }
1679
1680         if (s->avctx->hwaccel) {
1681             if ((ret = s->avctx->hwaccel->end_frame(s->avctx)) < 0) {
1682                 av_log(avctx, AV_LOG_ERROR,
1683                        "hardware accelerator failed to decode first field\n");
1684                 return ret;
1685             }
1686         }
1687
1688         for (i = 0; i < 4; i++) {
1689             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1690             if (s->picture_structure == PICT_BOTTOM_FIELD)
1691                 s->current_picture.f->data[i] +=
1692                     s->current_picture_ptr->f->linesize[i];
1693         }
1694     }
1695
1696     if (avctx->hwaccel) {
1697         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1698             return ret;
1699     }
1700
1701     return 0;
1702 }
1703
1704 #define DECODE_SLICE_ERROR -1
1705 #define DECODE_SLICE_OK     0
1706
1707 /**
1708  * Decode a slice.
1709  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1710  * @return DECODE_SLICE_ERROR if the slice is damaged,
1711  *         DECODE_SLICE_OK if this slice is OK
1712  */
1713 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1714                              const uint8_t **buf, int buf_size)
1715 {
1716     AVCodecContext *avctx = s->avctx;
1717     const int lowres      = s->avctx->lowres;
1718     const int field_pic   = s->picture_structure != PICT_FRAME;
1719     int ret;
1720
1721     s->resync_mb_x =
1722     s->resync_mb_y = -1;
1723
1724     av_assert0(mb_y < s->mb_height);
1725
1726     init_get_bits(&s->gb, *buf, buf_size * 8);
1727     if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1728         skip_bits(&s->gb, 3);
1729
1730     ff_mpeg1_clean_buffers(s);
1731     s->interlaced_dct = 0;
1732
1733     s->qscale = mpeg_get_qscale(s);
1734
1735     if (s->qscale == 0) {
1736         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1737         return AVERROR_INVALIDDATA;
1738     }
1739
1740     /* extra slice info */
1741     if (skip_1stop_8data_bits(&s->gb) < 0)
1742         return AVERROR_INVALIDDATA;
1743
1744     s->mb_x = 0;
1745
1746     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1747         skip_bits1(&s->gb);
1748     } else {
1749         while (get_bits_left(&s->gb) > 0) {
1750             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1751                                 MBINCR_VLC_BITS, 2);
1752             if (code < 0) {
1753                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1754                 return AVERROR_INVALIDDATA;
1755             }
1756             if (code >= 33) {
1757                 if (code == 33)
1758                     s->mb_x += 33;
1759                 /* otherwise, stuffing, nothing to do */
1760             } else {
1761                 s->mb_x += code;
1762                 break;
1763             }
1764         }
1765     }
1766
1767     if (s->mb_x >= (unsigned) s->mb_width) {
1768         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1769         return AVERROR_INVALIDDATA;
1770     }
1771
1772     if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1773         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1774         int start_code = -1;
1775         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1776         if (buf_end < *buf + buf_size)
1777             buf_end -= 4;
1778         s->mb_y = mb_y;
1779         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1780             return DECODE_SLICE_ERROR;
1781         *buf = buf_end;
1782         return DECODE_SLICE_OK;
1783     }
1784
1785     s->resync_mb_x = s->mb_x;
1786     s->resync_mb_y = s->mb_y = mb_y;
1787     s->mb_skip_run = 0;
1788     ff_init_block_index(s);
1789
1790     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1791         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1792             av_log(s->avctx, AV_LOG_DEBUG,
1793                    "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",
1794                    s->qscale,
1795                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1796                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1797                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1798                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1799                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1800                    s->progressive_sequence ? "ps"  : "",
1801                    s->progressive_frame    ? "pf"  : "",
1802                    s->alternate_scan       ? "alt" : "",
1803                    s->top_field_first      ? "top" : "",
1804                    s->intra_dc_precision, s->picture_structure,
1805                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1806                    s->q_scale_type, s->intra_vlc_format,
1807                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1808         }
1809     }
1810
1811     for (;;) {
1812         // If 1, we memcpy blocks in xvmcvideo.
1813         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1814             ff_xvmc_init_block(s); // set s->block
1815
1816         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1817             return ret;
1818
1819         // Note motion_val is normally NULL unless we want to extract the MVs.
1820         if (s->current_picture.motion_val[0] && !s->encoding) {
1821             const int wrap = s->b8_stride;
1822             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1823             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1824             int motion_x, motion_y, dir, i;
1825
1826             for (i = 0; i < 2; i++) {
1827                 for (dir = 0; dir < 2; dir++) {
1828                     if (s->mb_intra ||
1829                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1830                         motion_x = motion_y = 0;
1831                     } else if (s->mv_type == MV_TYPE_16X16 ||
1832                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1833                         motion_x = s->mv[dir][0][0];
1834                         motion_y = s->mv[dir][0][1];
1835                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1836                         motion_x = s->mv[dir][i][0];
1837                         motion_y = s->mv[dir][i][1];
1838                     }
1839
1840                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1841                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1842                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1843                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1844                     s->current_picture.ref_index [dir][b8_xy]     =
1845                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1846                     av_assert2(s->field_select[dir][i] == 0 ||
1847                                s->field_select[dir][i] == 1);
1848                 }
1849                 xy    += wrap;
1850                 b8_xy += 2;
1851             }
1852         }
1853
1854         s->dest[0] += 16 >> lowres;
1855         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1856         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1857
1858         ff_mpv_reconstruct_mb(s, s->block);
1859
1860         if (++s->mb_x >= s->mb_width) {
1861             const int mb_size = 16 >> s->avctx->lowres;
1862             int left;
1863
1864             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1865             ff_mpv_report_decode_progress(s);
1866
1867             s->mb_x  = 0;
1868             s->mb_y += 1 << field_pic;
1869
1870             if (s->mb_y >= s->mb_height) {
1871                 int left   = get_bits_left(&s->gb);
1872                 int is_d10 = s->chroma_format == 2 &&
1873                              s->pict_type == AV_PICTURE_TYPE_I &&
1874                              avctx->profile == 0 && avctx->level == 5 &&
1875                              s->intra_dc_precision == 2 &&
1876                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1877                              s->progressive_frame == 0
1878                              /* vbv_delay == 0xBBB || 0xE10 */;
1879
1880                 if (left >= 32 && !is_d10) {
1881                     GetBitContext gb = s->gb;
1882                     align_get_bits(&gb);
1883                     if (show_bits(&gb, 24) == 0x060E2B) {
1884                         av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
1885                         is_d10 = 1;
1886                     }
1887                     if (left > 32 && show_bits_long(&gb, 32) == 0x201) {
1888                         av_log(avctx, AV_LOG_DEBUG, "skipping m704 alpha (unsupported)\n");
1889                         goto eos;
1890                     }
1891                 }
1892
1893                 if (left < 0 ||
1894                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1895                     ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1896                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X at %d %d\n",
1897                            left, left>0 ? show_bits(&s->gb, FFMIN(left, 23)) : 0, s->mb_x, s->mb_y);
1898                     return AVERROR_INVALIDDATA;
1899                 } else
1900                     goto eos;
1901             }
1902             // There are some files out there which are missing the last slice
1903             // in cases where the slice is completely outside the visible
1904             // area, we detect this here instead of running into the end expecting
1905             // more data
1906             left = get_bits_left(&s->gb);
1907             if (s->mb_y >= ((s->height + 15) >> 4) &&
1908                 !s->progressive_sequence &&
1909                 left <= 25 &&
1910                 left >= 0 &&
1911                 s->mb_skip_run == -1 &&
1912                 (!left || show_bits(&s->gb, left) == 0))
1913                 goto eos;
1914
1915             ff_init_block_index(s);
1916         }
1917
1918         /* skip mb handling */
1919         if (s->mb_skip_run == -1) {
1920             /* read increment again */
1921             s->mb_skip_run = 0;
1922             for (;;) {
1923                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1924                                     MBINCR_VLC_BITS, 2);
1925                 if (code < 0) {
1926                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1927                     return AVERROR_INVALIDDATA;
1928                 }
1929                 if (code >= 33) {
1930                     if (code == 33) {
1931                         s->mb_skip_run += 33;
1932                     } else if (code == 35) {
1933                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1934                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1935                             return AVERROR_INVALIDDATA;
1936                         }
1937                         goto eos; /* end of slice */
1938                     }
1939                     /* otherwise, stuffing, nothing to do */
1940                 } else {
1941                     s->mb_skip_run += code;
1942                     break;
1943                 }
1944             }
1945             if (s->mb_skip_run) {
1946                 int i;
1947                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1948                     av_log(s->avctx, AV_LOG_ERROR,
1949                            "skipped MB in I-frame at %d %d\n", s->mb_x, s->mb_y);
1950                     return AVERROR_INVALIDDATA;
1951                 }
1952
1953                 /* skip mb */
1954                 s->mb_intra = 0;
1955                 for (i = 0; i < 12; i++)
1956                     s->block_last_index[i] = -1;
1957                 if (s->picture_structure == PICT_FRAME)
1958                     s->mv_type = MV_TYPE_16X16;
1959                 else
1960                     s->mv_type = MV_TYPE_FIELD;
1961                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1962                     /* if P type, zero motion vector is implied */
1963                     s->mv_dir             = MV_DIR_FORWARD;
1964                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1965                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1966                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1967                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1968                 } else {
1969                     /* if B type, reuse previous vectors and directions */
1970                     s->mv[0][0][0] = s->last_mv[0][0][0];
1971                     s->mv[0][0][1] = s->last_mv[0][0][1];
1972                     s->mv[1][0][0] = s->last_mv[1][0][0];
1973                     s->mv[1][0][1] = s->last_mv[1][0][1];
1974                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1975                     s->field_select[1][0] = (s->picture_structure - 1) & 1;
1976                 }
1977             }
1978         }
1979     }
1980 eos: // end of slice
1981     if (get_bits_left(&s->gb) < 0) {
1982         av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
1983         return AVERROR_INVALIDDATA;
1984     }
1985     *buf += (get_bits_count(&s->gb) - 1) / 8;
1986     ff_dlog(s, "Slice start:%d %d  end:%d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1987     return 0;
1988 }
1989
1990 static int slice_decode_thread(AVCodecContext *c, void *arg)
1991 {
1992     MpegEncContext *s   = *(void **) arg;
1993     const uint8_t *buf  = s->gb.buffer;
1994     int mb_y            = s->start_mb_y;
1995     const int field_pic = s->picture_structure != PICT_FRAME;
1996
1997     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1998
1999     for (;;) {
2000         uint32_t start_code;
2001         int ret;
2002
2003         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
2004         emms_c();
2005         ff_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2006                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
2007                 s->start_mb_y, s->end_mb_y, s->er.error_count);
2008         if (ret < 0) {
2009             if (c->err_recognition & AV_EF_EXPLODE)
2010                 return ret;
2011             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
2012                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2013                                 s->mb_x, s->mb_y,
2014                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2015         } else {
2016             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2017                             s->mb_x - 1, s->mb_y,
2018                             ER_AC_END | ER_DC_END | ER_MV_END);
2019         }
2020
2021         if (s->mb_y == s->end_mb_y)
2022             return 0;
2023
2024         start_code = -1;
2025         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2026         if (start_code < SLICE_MIN_START_CODE || start_code > SLICE_MAX_START_CODE)
2027             return AVERROR_INVALIDDATA;
2028         mb_y       = start_code - SLICE_MIN_START_CODE;
2029         if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2030             mb_y += (*buf&0xE0)<<2;
2031         mb_y <<= field_pic;
2032         if (s->picture_structure == PICT_BOTTOM_FIELD)
2033             mb_y++;
2034         if (mb_y >= s->end_mb_y)
2035             return AVERROR_INVALIDDATA;
2036     }
2037 }
2038
2039 /**
2040  * Handle slice ends.
2041  * @return 1 if it seems to be the last slice
2042  */
2043 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2044 {
2045     Mpeg1Context *s1  = avctx->priv_data;
2046     MpegEncContext *s = &s1->mpeg_enc_ctx;
2047
2048     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2049         return 0;
2050
2051     if (s->avctx->hwaccel) {
2052         int ret = s->avctx->hwaccel->end_frame(s->avctx);
2053         if (ret < 0) {
2054             av_log(avctx, AV_LOG_ERROR,
2055                    "hardware accelerator failed to decode picture\n");
2056             return ret;
2057         }
2058     }
2059
2060     /* end of slice reached */
2061     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
2062         /* end of image */
2063
2064         ff_er_frame_end(&s->er);
2065
2066         ff_mpv_frame_end(s);
2067
2068         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2069             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2070             if (ret < 0)
2071                 return ret;
2072             ff_print_debug_info(s, s->current_picture_ptr, pict);
2073             ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2074         } else {
2075             if (avctx->active_thread_type & FF_THREAD_FRAME)
2076                 s->picture_number++;
2077             /* latency of 1 frame for I- and P-frames */
2078             /* XXX: use another variable than picture_number */
2079             if (s->last_picture_ptr) {
2080                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2081                 if (ret < 0)
2082                     return ret;
2083                 ff_print_debug_info(s, s->last_picture_ptr, pict);
2084                 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2085             }
2086         }
2087
2088         return 1;
2089     } else {
2090         return 0;
2091     }
2092 }
2093
2094 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2095                                  const uint8_t *buf, int buf_size)
2096 {
2097     Mpeg1Context *s1  = avctx->priv_data;
2098     MpegEncContext *s = &s1->mpeg_enc_ctx;
2099     int width, height;
2100     int i, v, j;
2101
2102     init_get_bits(&s->gb, buf, buf_size * 8);
2103
2104     width  = get_bits(&s->gb, 12);
2105     height = get_bits(&s->gb, 12);
2106     if (width == 0 || height == 0) {
2107         av_log(avctx, AV_LOG_WARNING,
2108                "Invalid horizontal or vertical size value.\n");
2109         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2110             return AVERROR_INVALIDDATA;
2111     }
2112     s->aspect_ratio_info = get_bits(&s->gb, 4);
2113     if (s->aspect_ratio_info == 0) {
2114         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2115         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2116             return AVERROR_INVALIDDATA;
2117     }
2118     s->frame_rate_index = get_bits(&s->gb, 4);
2119     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2120         av_log(avctx, AV_LOG_WARNING,
2121                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2122         s->frame_rate_index = 1;
2123     }
2124     s->bit_rate = get_bits(&s->gb, 18) * 400LL;
2125     if (check_marker(s->avctx, &s->gb, "in sequence header") == 0) {
2126         return AVERROR_INVALIDDATA;
2127     }
2128
2129     s1->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2130     skip_bits(&s->gb, 1);
2131
2132     /* get matrix */
2133     if (get_bits1(&s->gb)) {
2134         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2135     } else {
2136         for (i = 0; i < 64; i++) {
2137             j = s->idsp.idct_permutation[i];
2138             v = ff_mpeg1_default_intra_matrix[i];
2139             s->intra_matrix[j]        = v;
2140             s->chroma_intra_matrix[j] = v;
2141         }
2142     }
2143     if (get_bits1(&s->gb)) {
2144         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2145     } else {
2146         for (i = 0; i < 64; i++) {
2147             int j = s->idsp.idct_permutation[i];
2148             v = ff_mpeg1_default_non_intra_matrix[i];
2149             s->inter_matrix[j]        = v;
2150             s->chroma_inter_matrix[j] = v;
2151         }
2152     }
2153
2154     if (show_bits(&s->gb, 23) != 0) {
2155         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2156         return AVERROR_INVALIDDATA;
2157     }
2158
2159     s->width  = width;
2160     s->height = height;
2161
2162     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2163     s->progressive_sequence = 1;
2164     s->progressive_frame    = 1;
2165     s->picture_structure    = PICT_FRAME;
2166     s->first_field          = 0;
2167     s->frame_pred_frame_dct = 1;
2168     s->chroma_format        = 1;
2169     s->codec_id             =
2170     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2171     s->out_format           = FMT_MPEG1;
2172     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2173     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
2174         s->low_delay = 1;
2175
2176     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2177         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%"PRId64", aspect_ratio_info: %d \n",
2178                s1->rc_buffer_size, s->bit_rate, s->aspect_ratio_info);
2179
2180     return 0;
2181 }
2182
2183 static int vcr2_init_sequence(AVCodecContext *avctx)
2184 {
2185     Mpeg1Context *s1  = avctx->priv_data;
2186     MpegEncContext *s = &s1->mpeg_enc_ctx;
2187     int i, v, ret;
2188
2189     /* start new MPEG-1 context decoding */
2190     s->out_format = FMT_MPEG1;
2191     if (s1->mpeg_enc_ctx_allocated) {
2192         ff_mpv_common_end(s);
2193         s1->mpeg_enc_ctx_allocated = 0;
2194     }
2195     s->width            = avctx->coded_width;
2196     s->height           = avctx->coded_height;
2197     avctx->has_b_frames = 0; // true?
2198     s->low_delay        = 1;
2199
2200     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2201     setup_hwaccel_for_pixfmt(avctx);
2202
2203     ff_mpv_idct_init(s);
2204     if ((ret = ff_mpv_common_init(s)) < 0)
2205         return ret;
2206     s1->mpeg_enc_ctx_allocated = 1;
2207
2208     for (i = 0; i < 64; i++) {
2209         int j = s->idsp.idct_permutation[i];
2210         v = ff_mpeg1_default_intra_matrix[i];
2211         s->intra_matrix[j]        = v;
2212         s->chroma_intra_matrix[j] = v;
2213
2214         v = ff_mpeg1_default_non_intra_matrix[i];
2215         s->inter_matrix[j]        = v;
2216         s->chroma_inter_matrix[j] = v;
2217     }
2218
2219     s->progressive_sequence  = 1;
2220     s->progressive_frame     = 1;
2221     s->picture_structure     = PICT_FRAME;
2222     s->first_field           = 0;
2223     s->frame_pred_frame_dct  = 1;
2224     s->chroma_format         = 1;
2225     if (s->codec_tag == AV_RL32("BW10")) {
2226         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2227     } else {
2228         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2229         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2230     }
2231     s1->save_width           = s->width;
2232     s1->save_height          = s->height;
2233     s1->save_progressive_seq = s->progressive_sequence;
2234     return 0;
2235 }
2236
2237 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2238                               const uint8_t *p, int buf_size)
2239 {
2240     Mpeg1Context *s1 = avctx->priv_data;
2241
2242     if (buf_size >= 6 &&
2243         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2244         p[4] == 3 && (p[5] & 0x40)) {
2245         /* extract A53 Part 4 CC data */
2246         int cc_count = p[5] & 0x1f;
2247         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2248             av_freep(&s1->a53_caption);
2249             s1->a53_caption_size = cc_count * 3;
2250             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2251             if (!s1->a53_caption) {
2252                 s1->a53_caption_size = 0;
2253             } else {
2254                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2255             }
2256             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
2257         }
2258         return 1;
2259     } else if (buf_size >= 2 &&
2260                p[0] == 0x03 && (p[1]&0x7f) == 0x01) {
2261         /* extract SCTE-20 CC data */
2262         GetBitContext gb;
2263         int cc_count = 0;
2264         int i;
2265
2266         init_get_bits(&gb, p + 2, buf_size - 2);
2267         cc_count = get_bits(&gb, 5);
2268         if (cc_count > 0) {
2269             av_freep(&s1->a53_caption);
2270             s1->a53_caption_size = cc_count * 3;
2271             s1->a53_caption      = av_mallocz(s1->a53_caption_size);
2272             if (!s1->a53_caption) {
2273                 s1->a53_caption_size = 0;
2274             } else {
2275                 uint8_t field, cc1, cc2;
2276                 uint8_t *cap = s1->a53_caption;
2277                 for (i = 0; i < cc_count && get_bits_left(&gb) >= 26; i++) {
2278                     skip_bits(&gb, 2); // priority
2279                     field = get_bits(&gb, 2);
2280                     skip_bits(&gb, 5); // line_offset
2281                     cc1 = get_bits(&gb, 8);
2282                     cc2 = get_bits(&gb, 8);
2283                     skip_bits(&gb, 1); // marker
2284
2285                     if (!field) { // forbidden
2286                         cap[0] = cap[1] = cap[2] = 0x00;
2287                     } else {
2288                         field = (field == 2 ? 1 : 0);
2289                         if (!s1->mpeg_enc_ctx.top_field_first) field = !field;
2290                         cap[0] = 0x04 | field;
2291                         cap[1] = ff_reverse[cc1];
2292                         cap[2] = ff_reverse[cc2];
2293                     }
2294                     cap += 3;
2295                 }
2296             }
2297             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
2298         }
2299         return 1;
2300     } else if (buf_size >= 11 &&
2301                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2302         /* extract DVD CC data
2303          *
2304          * uint32_t   user_data_start_code        0x000001B2    (big endian)
2305          * uint16_t   user_identifier             0x4343 "CC"
2306          * uint8_t    user_data_type_code         0x01
2307          * uint8_t    caption_block_size          0xF8
2308          * uint8_t
2309          *   bit 7    caption_odd_field_first     1=odd field (CC1/CC2) first  0=even field (CC3/CC4) first
2310          *   bit 6    caption_filler              0
2311          *   bit 5:1  caption_block_count         number of caption blocks (pairs of caption words = frames). Most DVDs use 15 per start of GOP.
2312          *   bit 0    caption_extra_field_added   1=one additional caption word
2313          *
2314          * struct caption_field_block {
2315          *   uint8_t
2316          *     bit 7:1 caption_filler             0x7F (all 1s)
2317          *     bit 0   caption_field_odd          1=odd field (this is CC1/CC2)  0=even field (this is CC3/CC4)
2318          *   uint8_t   caption_first_byte
2319          *   uint8_t   caption_second_byte
2320          * } caption_block[(caption_block_count * 2) + caption_extra_field_added];
2321          *
2322          * Some DVDs encode caption data for both fields with caption_field_odd=1. The only way to decode the fields
2323          * correctly is to start on the field indicated by caption_odd_field_first and count between odd/even fields.
2324          * Don't assume that the first caption word is the odd field. There do exist MPEG files in the wild that start
2325          * on the even field. There also exist DVDs in the wild that encode an odd field count and the
2326          * caption_extra_field_added/caption_odd_field_first bits change per packet to allow that. */
2327         int cc_count = 0;
2328         int i;
2329         // There is a caption count field in the data, but it is often
2330         // incorrect.  So count the number of captions present.
2331         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2332             cc_count++;
2333         // Transform the DVD format into A53 Part 4 format
2334         if (cc_count > 0) {
2335             av_freep(&s1->a53_caption);
2336             s1->a53_caption_size = cc_count * 6;
2337             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2338             if (!s1->a53_caption) {
2339                 s1->a53_caption_size = 0;
2340             } else {
2341                 uint8_t field1 = !!(p[4] & 0x80);
2342                 uint8_t *cap = s1->a53_caption;
2343                 p += 5;
2344                 for (i = 0; i < cc_count; i++) {
2345                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2346                     cap[1] = p[1];
2347                     cap[2] = p[2];
2348                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2349                     cap[4] = p[4];
2350                     cap[5] = p[5];
2351                     cap += 6;
2352                     p += 6;
2353                 }
2354             }
2355             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
2356         }
2357         return 1;
2358     }
2359     return 0;
2360 }
2361
2362 static void mpeg_decode_user_data(AVCodecContext *avctx,
2363                                   const uint8_t *p, int buf_size)
2364 {
2365     Mpeg1Context *s = avctx->priv_data;
2366     const uint8_t *buf_end = p + buf_size;
2367     Mpeg1Context *s1 = avctx->priv_data;
2368
2369 #if 0
2370     int i;
2371     for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2372         av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
2373     }
2374     av_log(avctx, AV_LOG_ERROR, "\n");
2375 #endif
2376
2377     if (buf_size > 29){
2378         int i;
2379         for(i=0; i<20; i++)
2380             if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2381                 s->tmpgexs= 1;
2382             }
2383     }
2384     /* we parse the DTG active format information */
2385     if (buf_end - p >= 5 &&
2386         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2387         int flags = p[4];
2388         p += 5;
2389         if (flags & 0x80) {
2390             /* skip event id */
2391             p += 2;
2392         }
2393         if (flags & 0x40) {
2394             if (buf_end - p < 1)
2395                 return;
2396             s1->has_afd = 1;
2397             s1->afd     = p[0] & 0x0f;
2398         }
2399     } else if (buf_end - p >= 6 &&
2400                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2401                p[4] == 0x03) { // S3D_video_format_length
2402         // the 0x7F mask ignores the reserved_bit value
2403         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2404
2405         if (S3D_video_format_type == 0x03 ||
2406             S3D_video_format_type == 0x04 ||
2407             S3D_video_format_type == 0x08 ||
2408             S3D_video_format_type == 0x23) {
2409
2410             s1->has_stereo3d = 1;
2411
2412             switch (S3D_video_format_type) {
2413             case 0x03:
2414                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2415                 break;
2416             case 0x04:
2417                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2418                 break;
2419             case 0x08:
2420                 s1->stereo3d.type = AV_STEREO3D_2D;
2421                 break;
2422             case 0x23:
2423                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2424                 break;
2425             }
2426         }
2427     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2428         return;
2429     }
2430 }
2431
2432 static void mpeg_decode_gop(AVCodecContext *avctx,
2433                             const uint8_t *buf, int buf_size)
2434 {
2435     Mpeg1Context *s1  = avctx->priv_data;
2436     MpegEncContext *s = &s1->mpeg_enc_ctx;
2437     int broken_link;
2438     int64_t tc;
2439
2440     init_get_bits(&s->gb, buf, buf_size * 8);
2441
2442     tc = s-> timecode_frame_start = get_bits(&s->gb, 25);
2443
2444 #if FF_API_PRIVATE_OPT
2445 FF_DISABLE_DEPRECATION_WARNINGS
2446     avctx->timecode_frame_start = tc;
2447 FF_ENABLE_DEPRECATION_WARNINGS
2448 #endif
2449
2450     s->closed_gop = get_bits1(&s->gb);
2451     /* broken_link indicates that after editing the
2452      * reference frames of the first B-Frames after GOP I-Frame
2453      * are missing (open gop) */
2454     broken_link = get_bits1(&s->gb);
2455
2456     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2457         char tcbuf[AV_TIMECODE_STR_SIZE];
2458         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2459         av_log(s->avctx, AV_LOG_DEBUG,
2460                "GOP (%s) closed_gop=%d broken_link=%d\n",
2461                tcbuf, s->closed_gop, broken_link);
2462     }
2463 }
2464
2465 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2466                          int *got_output, const uint8_t *buf, int buf_size)
2467 {
2468     Mpeg1Context *s = avctx->priv_data;
2469     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2470     const uint8_t *buf_ptr = buf;
2471     const uint8_t *buf_end = buf + buf_size;
2472     int ret, input_size;
2473     int last_code = 0, skip_frame = 0;
2474     int picture_start_code_seen = 0;
2475
2476     for (;;) {
2477         /* find next start code */
2478         uint32_t start_code = -1;
2479         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2480         if (start_code > 0x1ff) {
2481             if (!skip_frame) {
2482                 if (HAVE_THREADS &&
2483                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2484                     !avctx->hwaccel) {
2485                     int i;
2486                     av_assert0(avctx->thread_count > 1);
2487
2488                     avctx->execute(avctx, slice_decode_thread,
2489                                    &s2->thread_context[0], NULL,
2490                                    s->slice_count, sizeof(void *));
2491                     for (i = 0; i < s->slice_count; i++)
2492                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2493                 }
2494
2495                 ret = slice_end(avctx, picture);
2496                 if (ret < 0)
2497                     return ret;
2498                 else if (ret) {
2499                     // FIXME: merge with the stuff in mpeg_decode_slice
2500                     if (s2->last_picture_ptr || s2->low_delay)
2501                         *got_output = 1;
2502                 }
2503             }
2504             s2->pict_type = 0;
2505
2506             if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
2507                 return AVERROR_INVALIDDATA;
2508
2509             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2510         }
2511
2512         input_size = buf_end - buf_ptr;
2513
2514         if (avctx->debug & FF_DEBUG_STARTCODE)
2515             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2516                    start_code, buf_ptr - buf, input_size);
2517
2518         /* prepare data for next start code */
2519         switch (start_code) {
2520         case SEQ_START_CODE:
2521             if (last_code == 0) {
2522                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2523                 if (buf != avctx->extradata)
2524                     s->sync = 1;
2525             } else {
2526                 av_log(avctx, AV_LOG_ERROR,
2527                        "ignoring SEQ_START_CODE after %X\n", last_code);
2528                 if (avctx->err_recognition & AV_EF_EXPLODE)
2529                     return AVERROR_INVALIDDATA;
2530             }
2531             break;
2532
2533         case PICTURE_START_CODE:
2534             if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
2535                /* If it's a frame picture, there can't be more than one picture header.
2536                   Yet, it does happen and we need to handle it. */
2537                av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
2538                break;
2539             }
2540             picture_start_code_seen = 1;
2541
2542             if (s2->width <= 0 || s2->height <= 0) {
2543                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2544                        s2->width, s2->height);
2545                 return AVERROR_INVALIDDATA;
2546             }
2547
2548             if (s->tmpgexs){
2549                 s2->intra_dc_precision= 3;
2550                 s2->intra_matrix[0]= 1;
2551             }
2552             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2553                 !avctx->hwaccel && s->slice_count) {
2554                 int i;
2555
2556                 avctx->execute(avctx, slice_decode_thread,
2557                                s2->thread_context, NULL,
2558                                s->slice_count, sizeof(void *));
2559                 for (i = 0; i < s->slice_count; i++)
2560                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2561                 s->slice_count = 0;
2562             }
2563             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2564                 ret = mpeg_decode_postinit(avctx);
2565                 if (ret < 0) {
2566                     av_log(avctx, AV_LOG_ERROR,
2567                            "mpeg_decode_postinit() failure\n");
2568                     return ret;
2569                 }
2570
2571                 /* We have a complete image: we try to decompress it. */
2572                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2573                     s2->pict_type = 0;
2574                 s->first_slice = 1;
2575                 last_code      = PICTURE_START_CODE;
2576             } else {
2577                 av_log(avctx, AV_LOG_ERROR,
2578                        "ignoring pic after %X\n", last_code);
2579                 if (avctx->err_recognition & AV_EF_EXPLODE)
2580                     return AVERROR_INVALIDDATA;
2581             }
2582             break;
2583         case EXT_START_CODE:
2584             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2585
2586             switch (get_bits(&s2->gb, 4)) {
2587             case 0x1:
2588                 if (last_code == 0) {
2589                     mpeg_decode_sequence_extension(s);
2590                 } else {
2591                     av_log(avctx, AV_LOG_ERROR,
2592                            "ignoring seq ext after %X\n", last_code);
2593                     if (avctx->err_recognition & AV_EF_EXPLODE)
2594                         return AVERROR_INVALIDDATA;
2595                 }
2596                 break;
2597             case 0x2:
2598                 mpeg_decode_sequence_display_extension(s);
2599                 break;
2600             case 0x3:
2601                 mpeg_decode_quant_matrix_extension(s2);
2602                 break;
2603             case 0x7:
2604                 mpeg_decode_picture_display_extension(s);
2605                 break;
2606             case 0x8:
2607                 if (last_code == PICTURE_START_CODE) {
2608                     mpeg_decode_picture_coding_extension(s);
2609                 } else {
2610                     av_log(avctx, AV_LOG_ERROR,
2611                            "ignoring pic cod ext after %X\n", last_code);
2612                     if (avctx->err_recognition & AV_EF_EXPLODE)
2613                         return AVERROR_INVALIDDATA;
2614                 }
2615                 break;
2616             }
2617             break;
2618         case USER_START_CODE:
2619             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2620             break;
2621         case GOP_START_CODE:
2622             if (last_code == 0) {
2623                 s2->first_field = 0;
2624                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2625                 s->sync = 1;
2626             } else {
2627                 av_log(avctx, AV_LOG_ERROR,
2628                        "ignoring GOP_START_CODE after %X\n", last_code);
2629                 if (avctx->err_recognition & AV_EF_EXPLODE)
2630                     return AVERROR_INVALIDDATA;
2631             }
2632             break;
2633         default:
2634             if (start_code >= SLICE_MIN_START_CODE &&
2635                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2636                 if (s2->progressive_sequence && !s2->progressive_frame) {
2637                     s2->progressive_frame = 1;
2638                     av_log(s2->avctx, AV_LOG_ERROR,
2639                            "interlaced frame in progressive sequence, ignoring\n");
2640                 }
2641
2642                 if (s2->picture_structure == 0 ||
2643                     (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2644                     av_log(s2->avctx, AV_LOG_ERROR,
2645                            "picture_structure %d invalid, ignoring\n",
2646                            s2->picture_structure);
2647                     s2->picture_structure = PICT_FRAME;
2648                 }
2649
2650                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2651                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2652
2653                 if (s2->picture_structure == PICT_FRAME) {
2654                     s2->first_field = 0;
2655                     s2->v_edge_pos  = 16 * s2->mb_height;
2656                 } else {
2657                     s2->first_field ^= 1;
2658                     s2->v_edge_pos   = 8 * s2->mb_height;
2659                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2660                 }
2661             }
2662             if (start_code >= SLICE_MIN_START_CODE &&
2663                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2664                 const int field_pic = s2->picture_structure != PICT_FRAME;
2665                 int mb_y = start_code - SLICE_MIN_START_CODE;
2666                 last_code = SLICE_MIN_START_CODE;
2667                 if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2668                     mb_y += (*buf_ptr&0xE0)<<2;
2669
2670                 mb_y <<= field_pic;
2671                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2672                     mb_y++;
2673
2674                 if (buf_end - buf_ptr < 2) {
2675                     av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
2676                     return AVERROR_INVALIDDATA;
2677                 }
2678
2679                 if (mb_y >= s2->mb_height) {
2680                     av_log(s2->avctx, AV_LOG_ERROR,
2681                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2682                     return AVERROR_INVALIDDATA;
2683                 }
2684
2685                 if (!s2->last_picture_ptr) {
2686                     /* Skip B-frames if we do not have reference frames and
2687                      * GOP is not closed. */
2688                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2689                         if (!s2->closed_gop) {
2690                             skip_frame = 1;
2691                             av_log(s2->avctx, AV_LOG_DEBUG,
2692                                    "Skipping B slice due to open GOP\n");
2693                             break;
2694                         }
2695                     }
2696                 }
2697                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
2698                     s->sync = 1;
2699                 if (!s2->next_picture_ptr) {
2700                     /* Skip P-frames if we do not have a reference frame or
2701                      * we have an invalid header. */
2702                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2703                         skip_frame = 1;
2704                         av_log(s2->avctx, AV_LOG_DEBUG,
2705                                "Skipping P slice due to !sync\n");
2706                         break;
2707                     }
2708                 }
2709                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2710                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2711                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2712                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2713                     avctx->skip_frame >= AVDISCARD_ALL) {
2714                     skip_frame = 1;
2715                     break;
2716                 }
2717
2718                 if (!s->mpeg_enc_ctx_allocated)
2719                     break;
2720
2721                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2722                     if (mb_y < avctx->skip_top ||
2723                         mb_y >= s2->mb_height - avctx->skip_bottom)
2724                         break;
2725                 }
2726
2727                 if (!s2->pict_type) {
2728                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2729                     if (avctx->err_recognition & AV_EF_EXPLODE)
2730                         return AVERROR_INVALIDDATA;
2731                     break;
2732                 }
2733
2734                 if (s->first_slice) {
2735                     skip_frame     = 0;
2736                     s->first_slice = 0;
2737                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2738                         return ret;
2739                 }
2740                 if (!s2->current_picture_ptr) {
2741                     av_log(avctx, AV_LOG_ERROR,
2742                            "current_picture not initialized\n");
2743                     return AVERROR_INVALIDDATA;
2744                 }
2745
2746                 if (HAVE_THREADS &&
2747                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2748                     !avctx->hwaccel) {
2749                     int threshold = (s2->mb_height * s->slice_count +
2750                                      s2->slice_context_count / 2) /
2751                                     s2->slice_context_count;
2752                     av_assert0(avctx->thread_count > 1);
2753                     if (threshold <= mb_y) {
2754                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2755
2756                         thread_context->start_mb_y = mb_y;
2757                         thread_context->end_mb_y   = s2->mb_height;
2758                         if (s->slice_count) {
2759                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2760                             ret = ff_update_duplicate_context(thread_context, s2);
2761                             if (ret < 0)
2762                                 return ret;
2763                         }
2764                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2765                         s->slice_count++;
2766                     }
2767                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2768                 } else {
2769                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2770                     emms_c();
2771
2772                     if (ret < 0) {
2773                         if (avctx->err_recognition & AV_EF_EXPLODE)
2774                             return ret;
2775                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2776                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2777                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2778                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2779                     } else {
2780                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2781                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2782                                         ER_AC_END | ER_DC_END | ER_MV_END);
2783                     }
2784                 }
2785             }
2786             break;
2787         }
2788     }
2789 }
2790
2791 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2792                              int *got_output, AVPacket *avpkt)
2793 {
2794     const uint8_t *buf = avpkt->data;
2795     int ret;
2796     int buf_size = avpkt->size;
2797     Mpeg1Context *s = avctx->priv_data;
2798     AVFrame *picture = data;
2799     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2800
2801     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2802         /* special case for last picture */
2803         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2804             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2805             if (ret < 0)
2806                 return ret;
2807
2808             s2->next_picture_ptr = NULL;
2809
2810             *got_output = 1;
2811         }
2812         return buf_size;
2813     }
2814
2815     if (s2->avctx->flags & AV_CODEC_FLAG_TRUNCATED) {
2816         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2817                                            buf_size, NULL);
2818
2819         if (ff_combine_frame(&s2->parse_context, next,
2820                              (const uint8_t **) &buf, &buf_size) < 0)
2821             return buf_size;
2822     }
2823
2824     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2825     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2826                                            || s2->codec_tag == AV_RL32("BW10")
2827                                           ))
2828         vcr2_init_sequence(avctx);
2829
2830     s->slice_count = 0;
2831
2832     if (avctx->extradata && !s->extradata_decoded) {
2833         ret = decode_chunks(avctx, picture, got_output,
2834                             avctx->extradata, avctx->extradata_size);
2835         if (*got_output) {
2836             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2837             av_frame_unref(picture);
2838             *got_output = 0;
2839         }
2840         s->extradata_decoded = 1;
2841         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
2842             s2->current_picture_ptr = NULL;
2843             return ret;
2844         }
2845     }
2846
2847     ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
2848     if (ret<0 || *got_output) {
2849         s2->current_picture_ptr = NULL;
2850
2851         if (s2->timecode_frame_start != -1 && *got_output) {
2852             AVFrameSideData *tcside = av_frame_new_side_data(picture,
2853                                                              AV_FRAME_DATA_GOP_TIMECODE,
2854                                                              sizeof(int64_t));
2855             if (!tcside)
2856                 return AVERROR(ENOMEM);
2857             memcpy(tcside->data, &s2->timecode_frame_start, sizeof(int64_t));
2858
2859             s2->timecode_frame_start = -1;
2860         }
2861     }
2862
2863     return ret;
2864 }
2865
2866 static void flush(AVCodecContext *avctx)
2867 {
2868     Mpeg1Context *s = avctx->priv_data;
2869
2870     s->sync       = 0;
2871
2872     ff_mpeg_flush(avctx);
2873 }
2874
2875 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2876 {
2877     Mpeg1Context *s = avctx->priv_data;
2878
2879     if (s->mpeg_enc_ctx_allocated)
2880         ff_mpv_common_end(&s->mpeg_enc_ctx);
2881     av_freep(&s->a53_caption);
2882     return 0;
2883 }
2884
2885 AVCodec ff_mpeg1video_decoder = {
2886     .name                  = "mpeg1video",
2887     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2888     .type                  = AVMEDIA_TYPE_VIDEO,
2889     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2890     .priv_data_size        = sizeof(Mpeg1Context),
2891     .init                  = mpeg_decode_init,
2892     .close                 = mpeg_decode_end,
2893     .decode                = mpeg_decode_frame,
2894     .capabilities          = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2895                              AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2896                              AV_CODEC_CAP_SLICE_THREADS,
2897     .caps_internal         = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,
2898     .flush                 = flush,
2899     .max_lowres            = 3,
2900     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context),
2901     .hw_configs            = (const AVCodecHWConfigInternal*[]) {
2902 #if CONFIG_MPEG1_NVDEC_HWACCEL
2903                                HWACCEL_NVDEC(mpeg1),
2904 #endif
2905 #if CONFIG_MPEG1_VDPAU_HWACCEL
2906                                HWACCEL_VDPAU(mpeg1),
2907 #endif
2908 #if CONFIG_MPEG1_VIDEOTOOLBOX_HWACCEL
2909                                HWACCEL_VIDEOTOOLBOX(mpeg1),
2910 #endif
2911 #if CONFIG_MPEG1_XVMC_HWACCEL
2912                                HWACCEL_XVMC(mpeg1),
2913 #endif
2914                                NULL
2915                            },
2916 };
2917
2918 AVCodec ff_mpeg2video_decoder = {
2919     .name           = "mpeg2video",
2920     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2921     .type           = AVMEDIA_TYPE_VIDEO,
2922     .id             = AV_CODEC_ID_MPEG2VIDEO,
2923     .priv_data_size = sizeof(Mpeg1Context),
2924     .init           = mpeg_decode_init,
2925     .close          = mpeg_decode_end,
2926     .decode         = mpeg_decode_frame,
2927     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2928                       AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2929                       AV_CODEC_CAP_SLICE_THREADS,
2930     .caps_internal  = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,
2931     .flush          = flush,
2932     .max_lowres     = 3,
2933     .profiles       = NULL_IF_CONFIG_SMALL(ff_mpeg2_video_profiles),
2934     .hw_configs     = (const AVCodecHWConfigInternal*[]) {
2935 #if CONFIG_MPEG2_DXVA2_HWACCEL
2936                         HWACCEL_DXVA2(mpeg2),
2937 #endif
2938 #if CONFIG_MPEG2_D3D11VA_HWACCEL
2939                         HWACCEL_D3D11VA(mpeg2),
2940 #endif
2941 #if CONFIG_MPEG2_D3D11VA2_HWACCEL
2942                         HWACCEL_D3D11VA2(mpeg2),
2943 #endif
2944 #if CONFIG_MPEG2_NVDEC_HWACCEL
2945                         HWACCEL_NVDEC(mpeg2),
2946 #endif
2947 #if CONFIG_MPEG2_VAAPI_HWACCEL
2948                         HWACCEL_VAAPI(mpeg2),
2949 #endif
2950 #if CONFIG_MPEG2_VDPAU_HWACCEL
2951                         HWACCEL_VDPAU(mpeg2),
2952 #endif
2953 #if CONFIG_MPEG2_VIDEOTOOLBOX_HWACCEL
2954                         HWACCEL_VIDEOTOOLBOX(mpeg2),
2955 #endif
2956 #if CONFIG_MPEG2_XVMC_HWACCEL
2957                         HWACCEL_XVMC(mpeg2),
2958 #endif
2959                         NULL
2960                     },
2961 };
2962
2963 //legacy decoder
2964 AVCodec ff_mpegvideo_decoder = {
2965     .name           = "mpegvideo",
2966     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2967     .type           = AVMEDIA_TYPE_VIDEO,
2968     .id             = AV_CODEC_ID_MPEG2VIDEO,
2969     .priv_data_size = sizeof(Mpeg1Context),
2970     .init           = mpeg_decode_init,
2971     .close          = mpeg_decode_end,
2972     .decode         = mpeg_decode_frame,
2973     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
2974     .caps_internal  = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM,
2975     .flush          = flush,
2976     .max_lowres     = 3,
2977 };