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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 "idctdsp.h"
  40 #include "internal.h"
  41 #include "mpeg_er.h"
  42 #include "mpeg12.h"
  43 #include "mpeg12data.h"
  44 #include "mpegutils.h"
  45 #include "mpegvideo.h"
  46 #include "mpegvideodata.h"
  47 #include "thread.h"
  48 #include "version.h"
  49 #include "vdpau_compat.h"
  50 #include "xvmc_internal.h"
  51
  52 typedef struct Mpeg1Context {
  53     MpegEncContext mpeg_enc_ctx;
  54     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  55     int repeat_field;           /* true if we must repeat the field */
  56     AVPanScan pan_scan;         /* some temporary storage for the panscan */
  57     AVStereo3D stereo3d;
  58     int has_stereo3d;
  59     uint8_t *a53_caption;
  60     int a53_caption_size;
  61     uint8_t afd;
  62     int has_afd;
  63     int slice_count;
  64     AVRational save_aspect;
  65     int save_width, save_height, save_progressive_seq;
  66     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
  67     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
  68     int tmpgexs;
  69     int first_slice;
  70     int extradata_decoded;
  71 } Mpeg1Context;
  72
  73 #define MB_TYPE_ZERO_MV   0x20000000
  74
  75 static const uint32_t ptype2mb_type[7] = {
  76                     MB_TYPE_INTRA,
  77                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  78                     MB_TYPE_L0,
  79                     MB_TYPE_L0 | MB_TYPE_CBP,
  80     MB_TYPE_QUANT | MB_TYPE_INTRA,
  81     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  82     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
  83 };
  84
  85 static const uint32_t btype2mb_type[11] = {
  86                     MB_TYPE_INTRA,
  87                     MB_TYPE_L1,
  88                     MB_TYPE_L1   | MB_TYPE_CBP,
  89                     MB_TYPE_L0,
  90                     MB_TYPE_L0   | MB_TYPE_CBP,
  91                     MB_TYPE_L0L1,
  92                     MB_TYPE_L0L1 | MB_TYPE_CBP,
  93     MB_TYPE_QUANT | MB_TYPE_INTRA,
  94     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
  95     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
  96     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
  97 };
  98
  99 /* as H.263, but only 17 codes */
 100 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 101 {
 102     int code, sign, val, shift;
 103
 104     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
 105     if (code == 0)
 106         return pred;
 107     if (code < 0)
 108         return 0xffff;
 109
 110     sign  = get_bits1(&s->gb);
 111     shift = fcode - 1;
 112     val   = code;
 113     if (shift) {
 114         val  = (val - 1) << shift;
 115         val |= get_bits(&s->gb, shift);
 116         val++;
 117     }
 118     if (sign)
 119         val = -val;
 120     val += pred;
 121
 122     /* modulo decoding */
 123     return sign_extend(val, 5 + shift);
 124 }
 125
 126 #define check_scantable_index(ctx, x)                                         \
 127     do {                                                                      \
 128         if ((x) > 63) {                                                       \
 129             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
 130                    ctx->mb_x, ctx->mb_y);                                     \
 131             return AVERROR_INVALIDDATA;                                       \
 132         }                                                                     \
 133     } while (0)
 134
 135 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
 136                                            int16_t *block, int n)
 137 {
 138     int level, dc, diff, i, j, run;
 139     int component;
 140     RLTable *rl                  = &ff_rl_mpeg1;
 141     uint8_t *const scantable     = s->intra_scantable.permutated;
 142     const uint16_t *quant_matrix = s->intra_matrix;
 143     const int qscale             = s->qscale;
 144
 145     /* DC coefficient */
 146     component = (n <= 3 ? 0 : n - 4 + 1);
 147     diff = decode_dc(&s->gb, component);
 148     if (diff >= 0xffff)
 149         return AVERROR_INVALIDDATA;
 150     dc  = s->last_dc[component];
 151     dc += diff;
 152     s->last_dc[component] = dc;
 153     block[0] = dc * quant_matrix[0];
 154     ff_tlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
 155     i = 0;
 156     {
 157         OPEN_READER(re, &s->gb);
 158         UPDATE_CACHE(re, &s->gb);
 159         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 160             goto end;
 161
 162         /* now quantify & encode AC coefficients */
 163         for (;;) {
 164             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 165                        TEX_VLC_BITS, 2, 0);
 166
 167             if (level != 0) {
 168                 i += run;
 169                 check_scantable_index(s, i);
 170                 j = scantable[i];
 171                 level = (level * qscale * quant_matrix[j]) >> 4;
 172                 level = (level - 1) | 1;
 173                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 174                         SHOW_SBITS(re, &s->gb, 1);
 175                 SKIP_BITS(re, &s->gb, 1);
 176             } else {
 177                 /* escape */
 178                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 179                 LAST_SKIP_BITS(re, &s->gb, 6);
 180                 UPDATE_CACHE(re, &s->gb);
 181                 level = SHOW_SBITS(re, &s->gb, 8);
 182                 SKIP_BITS(re, &s->gb, 8);
 183                 if (level == -128) {
 184                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 185                     SKIP_BITS(re, &s->gb, 8);
 186                 } else if (level == 0) {
 187                     level = SHOW_UBITS(re, &s->gb, 8);
 188                     SKIP_BITS(re, &s->gb, 8);
 189                 }
 190                 i += run;
 191                 check_scantable_index(s, i);
 192                 j = scantable[i];
 193                 if (level < 0) {
 194                     level = -level;
 195                     level = (level * qscale * quant_matrix[j]) >> 4;
 196                     level = (level - 1) | 1;
 197                     level = -level;
 198                 } else {
 199                     level = (level * qscale * quant_matrix[j]) >> 4;
 200                     level = (level - 1) | 1;
 201                 }
 202             }
 203
 204             block[j] = level;
 205             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 206                break;
 207
 208             UPDATE_CACHE(re, &s->gb);
 209         }
 210 end:
 211         LAST_SKIP_BITS(re, &s->gb, 2);
 212         CLOSE_READER(re, &s->gb);
 213     }
 214     s->block_last_index[n] = i;
 215     return 0;
 216 }
 217
 218 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 219 {
 220     return mpeg1_decode_block_intra(s, block, n);
 221 }
 222
 223 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 224                                            int16_t *block, int n)
 225 {
 226     int level, i, j, run;
 227     RLTable *rl                  = &ff_rl_mpeg1;
 228     uint8_t *const scantable     = s->intra_scantable.permutated;
 229     const uint16_t *quant_matrix = s->inter_matrix;
 230     const int qscale             = s->qscale;
 231
 232     {
 233         OPEN_READER(re, &s->gb);
 234         i = -1;
 235         // special case for first coefficient, no need to add second VLC table
 236         UPDATE_CACHE(re, &s->gb);
 237         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 238             level = (3 * qscale * quant_matrix[0]) >> 5;
 239             level = (level - 1) | 1;
 240             if (GET_CACHE(re, &s->gb) & 0x40000000)
 241                 level = -level;
 242             block[0] = level;
 243             i++;
 244             SKIP_BITS(re, &s->gb, 2);
 245             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 246                 goto end;
 247         }
 248         /* now quantify & encode AC coefficients */
 249         for (;;) {
 250             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 251                        TEX_VLC_BITS, 2, 0);
 252
 253             if (level != 0) {
 254                 i += run;
 255                 check_scantable_index(s, i);
 256                 j = scantable[i];
 257                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 258                 level = (level - 1) | 1;
 259                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 260                         SHOW_SBITS(re, &s->gb, 1);
 261                 SKIP_BITS(re, &s->gb, 1);
 262             } else {
 263                 /* escape */
 264                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 265                 LAST_SKIP_BITS(re, &s->gb, 6);
 266                 UPDATE_CACHE(re, &s->gb);
 267                 level = SHOW_SBITS(re, &s->gb, 8);
 268                 SKIP_BITS(re, &s->gb, 8);
 269                 if (level == -128) {
 270                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 271                     SKIP_BITS(re, &s->gb, 8);
 272                 } else if (level == 0) {
 273                     level = SHOW_UBITS(re, &s->gb, 8);
 274                     SKIP_BITS(re, &s->gb, 8);
 275                 }
 276                 i += run;
 277                 check_scantable_index(s, i);
 278                 j = scantable[i];
 279                 if (level < 0) {
 280                     level = -level;
 281                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 282                     level = (level - 1) | 1;
 283                     level = -level;
 284                 } else {
 285                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 286                     level = (level - 1) | 1;
 287                 }
 288             }
 289
 290             block[j] = level;
 291             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 292                 break;
 293             UPDATE_CACHE(re, &s->gb);
 294         }
 295 end:
 296         LAST_SKIP_BITS(re, &s->gb, 2);
 297         CLOSE_READER(re, &s->gb);
 298     }
 299     s->block_last_index[n] = i;
 300     return 0;
 301 }
 302
 303 /**
 304  * Note: this function can read out of range and crash for corrupt streams.
 305  * Changing this would eat up any speed benefits it has.
 306  * Do not use "fast" flag if you need the code to be robust.
 307  */
 308 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
 309                                                 int16_t *block, int n)
 310 {
 311     int level, i, j, run;
 312     RLTable *rl              = &ff_rl_mpeg1;
 313     uint8_t *const scantable = s->intra_scantable.permutated;
 314     const int qscale         = s->qscale;
 315
 316     {
 317         OPEN_READER(re, &s->gb);
 318         i = -1;
 319         // Special case for first coefficient, no need to add second VLC table.
 320         UPDATE_CACHE(re, &s->gb);
 321         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 322             level = (3 * qscale) >> 1;
 323             level = (level - 1) | 1;
 324             if (GET_CACHE(re, &s->gb) & 0x40000000)
 325                 level = -level;
 326             block[0] = level;
 327             i++;
 328             SKIP_BITS(re, &s->gb, 2);
 329             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 330                 goto end;
 331         }
 332
 333         /* now quantify & encode AC coefficients */
 334         for (;;) {
 335             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 336                        TEX_VLC_BITS, 2, 0);
 337
 338             if (level != 0) {
 339                 i += run;
 340                 check_scantable_index(s, i);
 341                 j = scantable[i];
 342                 level = ((level * 2 + 1) * qscale) >> 1;
 343                 level = (level - 1) | 1;
 344                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 345                         SHOW_SBITS(re, &s->gb, 1);
 346                 SKIP_BITS(re, &s->gb, 1);
 347             } else {
 348                 /* escape */
 349                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 350                 LAST_SKIP_BITS(re, &s->gb, 6);
 351                 UPDATE_CACHE(re, &s->gb);
 352                 level = SHOW_SBITS(re, &s->gb, 8);
 353                 SKIP_BITS(re, &s->gb, 8);
 354                 if (level == -128) {
 355                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 356                     SKIP_BITS(re, &s->gb, 8);
 357                 } else if (level == 0) {
 358                     level = SHOW_UBITS(re, &s->gb, 8);
 359                     SKIP_BITS(re, &s->gb, 8);
 360                 }
 361                 i += run;
 362                 check_scantable_index(s, i);
 363                 j = scantable[i];
 364                 if (level < 0) {
 365                     level = -level;
 366                     level = ((level * 2 + 1) * qscale) >> 1;
 367                     level = (level - 1) | 1;
 368                     level = -level;
 369                 } else {
 370                     level = ((level * 2 + 1) * qscale) >> 1;
 371                     level = (level - 1) | 1;
 372                 }
 373             }
 374
 375             block[j] = level;
 376             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 377                 break;
 378             UPDATE_CACHE(re, &s->gb);
 379         }
 380 end:
 381         LAST_SKIP_BITS(re, &s->gb, 2);
 382         CLOSE_READER(re, &s->gb);
 383     }
 384     s->block_last_index[n] = i;
 385     return 0;
 386 }
 387
 388 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 389                                                int16_t *block, int n)
 390 {
 391     int level, i, j, run;
 392     RLTable *rl = &ff_rl_mpeg1;
 393     uint8_t *const scantable = s->intra_scantable.permutated;
 394     const uint16_t *quant_matrix;
 395     const int qscale = s->qscale;
 396     int mismatch;
 397
 398     mismatch = 1;
 399
 400     {
 401         OPEN_READER(re, &s->gb);
 402         i = -1;
 403         if (n < 4)
 404             quant_matrix = s->inter_matrix;
 405         else
 406             quant_matrix = s->chroma_inter_matrix;
 407
 408         // Special case for first coefficient, no need to add second VLC table.
 409         UPDATE_CACHE(re, &s->gb);
 410         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 411             level = (3 * qscale * quant_matrix[0]) >> 5;
 412             if (GET_CACHE(re, &s->gb) & 0x40000000)
 413                 level = -level;
 414             block[0]  = level;
 415             mismatch ^= level;
 416             i++;
 417             SKIP_BITS(re, &s->gb, 2);
 418             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 419                 goto end;
 420         }
 421
 422         /* now quantify & encode AC coefficients */
 423         for (;;) {
 424             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 425                        TEX_VLC_BITS, 2, 0);
 426
 427             if (level != 0) {
 428                 i += run;
 429                 check_scantable_index(s, i);
 430                 j = scantable[i];
 431                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 432                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 433                         SHOW_SBITS(re, &s->gb, 1);
 434                 SKIP_BITS(re, &s->gb, 1);
 435             } else {
 436                 /* escape */
 437                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 438                 LAST_SKIP_BITS(re, &s->gb, 6);
 439                 UPDATE_CACHE(re, &s->gb);
 440                 level = SHOW_SBITS(re, &s->gb, 12);
 441                 SKIP_BITS(re, &s->gb, 12);
 442
 443                 i += run;
 444                 check_scantable_index(s, i);
 445                 j = scantable[i];
 446                 if (level < 0) {
 447                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 448                     level = -level;
 449                 } else {
 450                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 451                 }
 452             }
 453
 454             mismatch ^= level;
 455             block[j]  = level;
 456             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 457                 break;
 458             UPDATE_CACHE(re, &s->gb);
 459         }
 460 end:
 461         LAST_SKIP_BITS(re, &s->gb, 2);
 462         CLOSE_READER(re, &s->gb);
 463     }
 464     block[63] ^= (mismatch & 1);
 465
 466     s->block_last_index[n] = i;
 467     return 0;
 468 }
 469
 470 /**
 471  * Note: this function can read out of range and crash for corrupt streams.
 472  * Changing this would eat up any speed benefits it has.
 473  * Do not use "fast" flag if you need the code to be robust.
 474  */
 475 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 476                                                     int16_t *block, int n)
 477 {
 478     int level, i, j, run;
 479     RLTable *rl              = &ff_rl_mpeg1;
 480     uint8_t *const scantable = s->intra_scantable.permutated;
 481     const int qscale         = s->qscale;
 482     OPEN_READER(re, &s->gb);
 483     i = -1;
 484
 485     // special case for first coefficient, no need to add second VLC table
 486     UPDATE_CACHE(re, &s->gb);
 487     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 488         level = (3 * qscale) >> 1;
 489         if (GET_CACHE(re, &s->gb) & 0x40000000)
 490             level = -level;
 491         block[0] = level;
 492         i++;
 493         SKIP_BITS(re, &s->gb, 2);
 494         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 495             goto end;
 496     }
 497
 498     /* now quantify & encode AC coefficients */
 499     for (;;) {
 500         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 501
 502         if (level != 0) {
 503             i += run;
 504             j = scantable[i];
 505             level = ((level * 2 + 1) * qscale) >> 1;
 506             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 507                     SHOW_SBITS(re, &s->gb, 1);
 508             SKIP_BITS(re, &s->gb, 1);
 509         } else {
 510             /* escape */
 511             run = SHOW_UBITS(re, &s->gb, 6) + 1;
 512             LAST_SKIP_BITS(re, &s->gb, 6);
 513             UPDATE_CACHE(re, &s->gb);
 514             level = SHOW_SBITS(re, &s->gb, 12);
 515             SKIP_BITS(re, &s->gb, 12);
 516
 517             i += run;
 518             j = scantable[i];
 519             if (level < 0) {
 520                 level = ((-level * 2 + 1) * qscale) >> 1;
 521                 level = -level;
 522             } else {
 523                 level = ((level * 2 + 1) * qscale) >> 1;
 524             }
 525         }
 526
 527         block[j] = level;
 528         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
 529             break;
 530
 531         UPDATE_CACHE(re, &s->gb);
 532     }
 533 end:
 534     LAST_SKIP_BITS(re, &s->gb, 2);
 535     CLOSE_READER(re, &s->gb);
 536     s->block_last_index[n] = i;
 537     return 0;
 538 }
 539
 540 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
 541                                            int16_t *block, int n)
 542 {
 543     int level, dc, diff, i, j, run;
 544     int component;
 545     RLTable *rl;
 546     uint8_t *const scantable = s->intra_scantable.permutated;
 547     const uint16_t *quant_matrix;
 548     const int qscale = s->qscale;
 549     int mismatch;
 550
 551     /* DC coefficient */
 552     if (n < 4) {
 553         quant_matrix = s->intra_matrix;
 554         component    = 0;
 555     } else {
 556         quant_matrix = s->chroma_intra_matrix;
 557         component    = (n & 1) + 1;
 558     }
 559     diff = decode_dc(&s->gb, component);
 560     if (diff >= 0xffff)
 561         return AVERROR_INVALIDDATA;
 562     dc  = s->last_dc[component];
 563     dc += diff;
 564     s->last_dc[component] = dc;
 565     block[0] = dc << (3 - s->intra_dc_precision);
 566     ff_tlog(s->avctx, "dc=%d\n", block[0]);
 567     mismatch = block[0] ^ 1;
 568     i = 0;
 569     if (s->intra_vlc_format)
 570         rl = &ff_rl_mpeg2;
 571     else
 572         rl = &ff_rl_mpeg1;
 573
 574     {
 575         OPEN_READER(re, &s->gb);
 576         /* now quantify & encode AC coefficients */
 577         for (;;) {
 578             UPDATE_CACHE(re, &s->gb);
 579             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 580                        TEX_VLC_BITS, 2, 0);
 581
 582             if (level == 127) {
 583                 break;
 584             } else if (level != 0) {
 585                 i += run;
 586                 check_scantable_index(s, i);
 587                 j = scantable[i];
 588                 level = (level * qscale * quant_matrix[j]) >> 4;
 589                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 590                         SHOW_SBITS(re, &s->gb, 1);
 591                 LAST_SKIP_BITS(re, &s->gb, 1);
 592             } else {
 593                 /* escape */
 594                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 595                 LAST_SKIP_BITS(re, &s->gb, 6);
 596                 UPDATE_CACHE(re, &s->gb);
 597                 level = SHOW_SBITS(re, &s->gb, 12);
 598                 SKIP_BITS(re, &s->gb, 12);
 599                 i += run;
 600                 check_scantable_index(s, i);
 601                 j = scantable[i];
 602                 if (level < 0) {
 603                     level = (-level * qscale * quant_matrix[j]) >> 4;
 604                     level = -level;
 605                 } else {
 606                     level = (level * qscale * quant_matrix[j]) >> 4;
 607                 }
 608             }
 609
 610             mismatch ^= level;
 611             block[j]  = level;
 612         }
 613         CLOSE_READER(re, &s->gb);
 614     }
 615     block[63] ^= mismatch & 1;
 616
 617     s->block_last_index[n] = i;
 618     return 0;
 619 }
 620
 621 /**
 622  * Note: this function can read out of range and crash for corrupt streams.
 623  * Changing this would eat up any speed benefits it has.
 624  * Do not use "fast" flag if you need the code to be robust.
 625  */
 626 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
 627                                                 int16_t *block, int n)
 628 {
 629     int level, dc, diff, i, j, run;
 630     int component;
 631     RLTable *rl;
 632     uint8_t *const scantable = s->intra_scantable.permutated;
 633     const uint16_t *quant_matrix;
 634     const int qscale = s->qscale;
 635
 636     /* DC coefficient */
 637     if (n < 4) {
 638         quant_matrix = s->intra_matrix;
 639         component    = 0;
 640     } else {
 641         quant_matrix = s->chroma_intra_matrix;
 642         component    = (n & 1) + 1;
 643     }
 644     diff = decode_dc(&s->gb, component);
 645     if (diff >= 0xffff)
 646         return AVERROR_INVALIDDATA;
 647     dc = s->last_dc[component];
 648     dc += diff;
 649     s->last_dc[component] = dc;
 650     block[0] = dc << (3 - s->intra_dc_precision);
 651     i = 0;
 652     if (s->intra_vlc_format)
 653         rl = &ff_rl_mpeg2;
 654     else
 655         rl = &ff_rl_mpeg1;
 656
 657     {
 658         OPEN_READER(re, &s->gb);
 659         /* now quantify & encode AC coefficients */
 660         for (;;) {
 661             UPDATE_CACHE(re, &s->gb);
 662             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 663                        TEX_VLC_BITS, 2, 0);
 664
 665             if (level >= 64 || i > 63) {
 666                 break;
 667             } else if (level != 0) {
 668                 i += run;
 669                 j = scantable[i];
 670                 level = (level * qscale * quant_matrix[j]) >> 4;
 671                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 672                         SHOW_SBITS(re, &s->gb, 1);
 673                 LAST_SKIP_BITS(re, &s->gb, 1);
 674             } else {
 675                 /* escape */
 676                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 677                 LAST_SKIP_BITS(re, &s->gb, 6);
 678                 UPDATE_CACHE(re, &s->gb);
 679                 level = SHOW_SBITS(re, &s->gb, 12);
 680                 SKIP_BITS(re, &s->gb, 12);
 681                 i += run;
 682                 j = scantable[i];
 683                 if (level < 0) {
 684                     level = (-level * qscale * quant_matrix[j]) >> 4;
 685                     level = -level;
 686                 } else {
 687                     level = (level * qscale * quant_matrix[j]) >> 4;
 688                 }
 689             }
 690
 691             block[j] = level;
 692         }
 693         CLOSE_READER(re, &s->gb);
 694     }
 695
 696     s->block_last_index[n] = i;
 697     return 0;
 698 }
 699
 700 /******************************************/
 701 /* decoding */
 702
 703 static inline int get_dmv(MpegEncContext *s)
 704 {
 705     if (get_bits1(&s->gb))
 706         return 1 - (get_bits1(&s->gb) << 1);
 707     else
 708         return 0;
 709 }
 710
 711 static inline int get_qscale(MpegEncContext *s)
 712 {
 713     int qscale = get_bits(&s->gb, 5);
 714     if (s->q_scale_type)
 715         return ff_mpeg2_non_linear_qscale[qscale];
 716     else
 717         return qscale << 1;
 718 }
 719
 720
 721 /* motion type (for MPEG-2) */
 722 #define MT_FIELD 1
 723 #define MT_FRAME 2
 724 #define MT_16X8  2
 725 #define MT_DMV   3
 726
 727 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 728 {
 729     int i, j, k, cbp, val, mb_type, motion_type;
 730     const int mb_block_count = 4 + (1 << s->chroma_format);
 731     int ret;
 732
 733     ff_tlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 734
 735     av_assert2(s->mb_skipped == 0);
 736
 737     if (s->mb_skip_run-- != 0) {
 738         if (s->pict_type == AV_PICTURE_TYPE_P) {
 739             s->mb_skipped = 1;
 740             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 741                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 742         } else {
 743             int mb_type;
 744
 745             if (s->mb_x)
 746                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 747             else
 748                 // FIXME not sure if this is allowed in MPEG at all
 749                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
 750             if (IS_INTRA(mb_type)) {
 751                 av_log(s->avctx, AV_LOG_ERROR, "skip with previntra\n");
 752                 return AVERROR_INVALIDDATA;
 753             }
 754             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 755                 mb_type | MB_TYPE_SKIP;
 756
 757             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 758                 s->mb_skipped = 1;
 759         }
 760
 761         return 0;
 762     }
 763
 764     switch (s->pict_type) {
 765     default:
 766     case AV_PICTURE_TYPE_I:
 767         if (get_bits1(&s->gb) == 0) {
 768             if (get_bits1(&s->gb) == 0) {
 769                 av_log(s->avctx, AV_LOG_ERROR,
 770                        "invalid mb type in I Frame at %d %d\n",
 771                        s->mb_x, s->mb_y);
 772                 return AVERROR_INVALIDDATA;
 773             }
 774             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 775         } else {
 776             mb_type = MB_TYPE_INTRA;
 777         }
 778         break;
 779     case AV_PICTURE_TYPE_P:
 780         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 781         if (mb_type < 0) {
 782             av_log(s->avctx, AV_LOG_ERROR,
 783                    "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 784             return AVERROR_INVALIDDATA;
 785         }
 786         mb_type = ptype2mb_type[mb_type];
 787         break;
 788     case AV_PICTURE_TYPE_B:
 789         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 790         if (mb_type < 0) {
 791             av_log(s->avctx, AV_LOG_ERROR,
 792                    "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 793             return AVERROR_INVALIDDATA;
 794         }
 795         mb_type = btype2mb_type[mb_type];
 796         break;
 797     }
 798     ff_tlog(s->avctx, "mb_type=%x\n", mb_type);
 799 //    motion_type = 0; /* avoid warning */
 800     if (IS_INTRA(mb_type)) {
 801         s->bdsp.clear_blocks(s->block[0]);
 802
 803         if (!s->chroma_y_shift)
 804             s->bdsp.clear_blocks(s->block[6]);
 805
 806         /* compute DCT type */
 807         // FIXME: add an interlaced_dct coded var?
 808         if (s->picture_structure == PICT_FRAME &&
 809             !s->frame_pred_frame_dct)
 810             s->interlaced_dct = get_bits1(&s->gb);
 811
 812         if (IS_QUANT(mb_type))
 813             s->qscale = get_qscale(s);
 814
 815         if (s->concealment_motion_vectors) {
 816             /* just parse them */
 817             if (s->picture_structure != PICT_FRAME)
 818                 skip_bits1(&s->gb);  /* field select */
 819
 820             s->mv[0][0][0]      =
 821             s->last_mv[0][0][0] =
 822             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
 823                                                      s->last_mv[0][0][0]);
 824             s->mv[0][0][1]      =
 825             s->last_mv[0][0][1] =
 826             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
 827                                                      s->last_mv[0][0][1]);
 828
 829             check_marker(&s->gb, "after concealment_motion_vectors");
 830         } else {
 831             /* reset mv prediction */
 832             memset(s->last_mv, 0, sizeof(s->last_mv));
 833         }
 834         s->mb_intra = 1;
 835         // if 1, we memcpy blocks in xvmcvideo
 836         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
 837             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 838
 839         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 840             if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
 841                 for (i = 0; i < 6; i++)
 842                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 843             } else {
 844                 for (i = 0; i < mb_block_count; i++)
 845                     if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 846                         return ret;
 847             }
 848         } else {
 849             for (i = 0; i < 6; i++)
 850                 if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 851                     return ret;
 852         }
 853     } else {
 854         if (mb_type & MB_TYPE_ZERO_MV) {
 855             av_assert2(mb_type & MB_TYPE_CBP);
 856
 857             s->mv_dir = MV_DIR_FORWARD;
 858             if (s->picture_structure == PICT_FRAME) {
 859                 if (s->picture_structure == PICT_FRAME
 860                     && !s->frame_pred_frame_dct)
 861                     s->interlaced_dct = get_bits1(&s->gb);
 862                 s->mv_type = MV_TYPE_16X16;
 863             } else {
 864                 s->mv_type            = MV_TYPE_FIELD;
 865                 mb_type              |= MB_TYPE_INTERLACED;
 866                 s->field_select[0][0] = s->picture_structure - 1;
 867             }
 868
 869             if (IS_QUANT(mb_type))
 870                 s->qscale = get_qscale(s);
 871
 872             s->last_mv[0][0][0] = 0;
 873             s->last_mv[0][0][1] = 0;
 874             s->last_mv[0][1][0] = 0;
 875             s->last_mv[0][1][1] = 0;
 876             s->mv[0][0][0]      = 0;
 877             s->mv[0][0][1]      = 0;
 878         } else {
 879             av_assert2(mb_type & MB_TYPE_L0L1);
 880             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 881             /* get additional motion vector type */
 882             if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) {
 883                 motion_type = MT_FRAME;
 884             } else {
 885                 motion_type = get_bits(&s->gb, 2);
 886                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 887                     s->interlaced_dct = get_bits1(&s->gb);
 888             }
 889
 890             if (IS_QUANT(mb_type))
 891                 s->qscale = get_qscale(s);
 892
 893             /* motion vectors */
 894             s->mv_dir = (mb_type >> 13) & 3;
 895             ff_tlog(s->avctx, "motion_type=%d\n", motion_type);
 896             switch (motion_type) {
 897             case MT_FRAME: /* or MT_16X8 */
 898                 if (s->picture_structure == PICT_FRAME) {
 899                     mb_type   |= MB_TYPE_16x16;
 900                     s->mv_type = MV_TYPE_16X16;
 901                     for (i = 0; i < 2; i++) {
 902                         if (USES_LIST(mb_type, i)) {
 903                             /* MT_FRAME */
 904                             s->mv[i][0][0]      =
 905                             s->last_mv[i][0][0] =
 906                             s->last_mv[i][1][0] =
 907                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 908                                                    s->last_mv[i][0][0]);
 909                             s->mv[i][0][1]      =
 910                             s->last_mv[i][0][1] =
 911                             s->last_mv[i][1][1] =
 912                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 913                                                    s->last_mv[i][0][1]);
 914                             /* full_pel: only for MPEG-1 */
 915                             if (s->full_pel[i]) {
 916                                 s->mv[i][0][0] <<= 1;
 917                                 s->mv[i][0][1] <<= 1;
 918                             }
 919                         }
 920                     }
 921                 } else {
 922                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 923                     s->mv_type = MV_TYPE_16X8;
 924                     for (i = 0; i < 2; i++) {
 925                         if (USES_LIST(mb_type, i)) {
 926                             /* MT_16X8 */
 927                             for (j = 0; j < 2; j++) {
 928                                 s->field_select[i][j] = get_bits1(&s->gb);
 929                                 for (k = 0; k < 2; k++) {
 930                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 931                                                              s->last_mv[i][j][k]);
 932                                     s->last_mv[i][j][k] = val;
 933                                     s->mv[i][j][k]      = val;
 934                                 }
 935                             }
 936                         }
 937                     }
 938                 }
 939                 break;
 940             case MT_FIELD:
 941                 s->mv_type = MV_TYPE_FIELD;
 942                 if (s->picture_structure == PICT_FRAME) {
 943                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 944                     for (i = 0; i < 2; i++) {
 945                         if (USES_LIST(mb_type, i)) {
 946                             for (j = 0; j < 2; j++) {
 947                                 s->field_select[i][j] = get_bits1(&s->gb);
 948                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 949                                                          s->last_mv[i][j][0]);
 950                                 s->last_mv[i][j][0] = val;
 951                                 s->mv[i][j][0]      = val;
 952                                 ff_tlog(s->avctx, "fmx=%d\n", val);
 953                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 954                                                          s->last_mv[i][j][1] >> 1);
 955                                 s->last_mv[i][j][1] = 2 * val;
 956                                 s->mv[i][j][1]      = val;
 957                                 ff_tlog(s->avctx, "fmy=%d\n", val);
 958                             }
 959                         }
 960                     }
 961                 } else {
 962                     av_assert0(!s->progressive_sequence);
 963                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 964                     for (i = 0; i < 2; i++) {
 965                         if (USES_LIST(mb_type, i)) {
 966                             s->field_select[i][0] = get_bits1(&s->gb);
 967                             for (k = 0; k < 2; k++) {
 968                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 969                                                          s->last_mv[i][0][k]);
 970                                 s->last_mv[i][0][k] = val;
 971                                 s->last_mv[i][1][k] = val;
 972                                 s->mv[i][0][k]      = val;
 973                             }
 974                         }
 975                     }
 976                 }
 977                 break;
 978             case MT_DMV:
 979                 if (s->progressive_sequence){
 980                     av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
 981                     return AVERROR_INVALIDDATA;
 982                 }
 983                 s->mv_type = MV_TYPE_DMV;
 984                 for (i = 0; i < 2; i++) {
 985                     if (USES_LIST(mb_type, i)) {
 986                         int dmx, dmy, mx, my, m;
 987                         const int my_shift = s->picture_structure == PICT_FRAME;
 988
 989                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 990                                                 s->last_mv[i][0][0]);
 991                         s->last_mv[i][0][0] = mx;
 992                         s->last_mv[i][1][0] = mx;
 993                         dmx = get_dmv(s);
 994                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 995                                                  s->last_mv[i][0][1] >> my_shift);
 996                         dmy = get_dmv(s);
 997
 998
 999                         s->last_mv[i][0][1] = my << my_shift;
1000                         s->last_mv[i][1][1] = my << my_shift;
1001
1002                         s->mv[i][0][0] = mx;
1003                         s->mv[i][0][1] = my;
1004                         s->mv[i][1][0] = mx; // not used
1005                         s->mv[i][1][1] = my; // not used
1006
1007                         if (s->picture_structure == PICT_FRAME) {
1008                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1009
1010                             // m = 1 + 2 * s->top_field_first;
1011                             m = s->top_field_first ? 1 : 3;
1012
1013                             /* top -> top pred */
1014                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1015                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1016                             m = 4 - m;
1017                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1018                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1019                         } else {
1020                             mb_type |= MB_TYPE_16x16;
1021
1022                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1023                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1024                             if (s->picture_structure == PICT_TOP_FIELD)
1025                                 s->mv[i][2][1]--;
1026                             else
1027                                 s->mv[i][2][1]++;
1028                         }
1029                     }
1030                 }
1031                 break;
1032             default:
1033                 av_log(s->avctx, AV_LOG_ERROR,
1034                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1035                 return AVERROR_INVALIDDATA;
1036             }
1037         }
1038
1039         s->mb_intra = 0;
1040         if (HAS_CBP(mb_type)) {
1041             s->bdsp.clear_blocks(s->block[0]);
1042
1043             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1044             if (mb_block_count > 6) {
1045                 cbp <<= mb_block_count - 6;
1046                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
1047                 s->bdsp.clear_blocks(s->block[6]);
1048             }
1049             if (cbp <= 0) {
1050                 av_log(s->avctx, AV_LOG_ERROR,
1051                        "invalid cbp %d at %d %d\n", cbp, s->mb_x, s->mb_y);
1052                 return AVERROR_INVALIDDATA;
1053             }
1054
1055             // if 1, we memcpy blocks in xvmcvideo
1056             if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1057                 ff_xvmc_pack_pblocks(s, cbp);
1058
1059             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1060                 if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1061                     for (i = 0; i < 6; i++) {
1062                         if (cbp & 32)
1063                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1064                         else
1065                             s->block_last_index[i] = -1;
1066                         cbp += cbp;
1067                     }
1068                 } else {
1069                     cbp <<= 12 - mb_block_count;
1070
1071                     for (i = 0; i < mb_block_count; i++) {
1072                         if (cbp & (1 << 11)) {
1073                             if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
1074                                 return ret;
1075                         } else {
1076                             s->block_last_index[i] = -1;
1077                         }
1078                         cbp += cbp;
1079                     }
1080                 }
1081             } else {
1082                 if (s->avctx->flags2 & AV_CODEC_FLAG2_FAST) {
1083                     for (i = 0; i < 6; i++) {
1084                         if (cbp & 32)
1085                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1086                         else
1087                             s->block_last_index[i] = -1;
1088                         cbp += cbp;
1089                     }
1090                 } else {
1091                     for (i = 0; i < 6; i++) {
1092                         if (cbp & 32) {
1093                             if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
1094                                 return ret;
1095                         } else {
1096                             s->block_last_index[i] = -1;
1097                         }
1098                         cbp += cbp;
1099                     }
1100                 }
1101             }
1102         } else {
1103             for (i = 0; i < 12; i++)
1104                 s->block_last_index[i] = -1;
1105         }
1106     }
1107
1108     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1109
1110     return 0;
1111 }
1112
1113 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1114 {
1115     Mpeg1Context *s    = avctx->priv_data;
1116     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1117
1118     ff_mpv_decode_defaults(s2);
1119
1120     if (   avctx->codec_tag != AV_RL32("VCR2")
1121         && avctx->codec_tag != AV_RL32("BW10"))
1122         avctx->coded_width = avctx->coded_height = 0; // do not trust dimensions from input
1123     ff_mpv_decode_init(s2, avctx);
1124
1125     s->mpeg_enc_ctx.avctx  = avctx;
1126
1127     /* we need some permutation to store matrices,
1128      * until the decoder sets the real permutation. */
1129     ff_mpv_idct_init(s2);
1130     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1131     ff_mpeg12_init_vlcs();
1132
1133     s2->chroma_format              = 1;
1134     s->mpeg_enc_ctx_allocated      = 0;
1135     s->mpeg_enc_ctx.picture_number = 0;
1136     s->repeat_field                = 0;
1137     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1138     avctx->color_range             = AVCOL_RANGE_MPEG;
1139     return 0;
1140 }
1141
1142 #if HAVE_THREADS
1143 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1144                                              const AVCodecContext *avctx_from)
1145 {
1146     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1147     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1148     int err;
1149
1150     if (avctx == avctx_from               ||
1151         !ctx_from->mpeg_enc_ctx_allocated ||
1152         !s1->context_initialized)
1153         return 0;
1154
1155     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1156     if (err)
1157         return err;
1158
1159     if (!ctx->mpeg_enc_ctx_allocated)
1160         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1161
1162     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1163         s->picture_number++;
1164
1165     return 0;
1166 }
1167 #endif
1168
1169 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1170                                  const uint8_t *new_perm)
1171 {
1172     uint16_t temp_matrix[64];
1173     int i;
1174
1175     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1176
1177     for (i = 0; i < 64; i++)
1178         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1179 }
1180
1181 static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1182 #if CONFIG_MPEG1_XVMC_HWACCEL
1183     AV_PIX_FMT_XVMC,
1184 #endif
1185 #if CONFIG_MPEG1_VDPAU_DECODER && FF_API_VDPAU
1186     AV_PIX_FMT_VDPAU_MPEG1,
1187 #endif
1188 #if CONFIG_MPEG1_VDPAU_HWACCEL
1189     AV_PIX_FMT_VDPAU,
1190 #endif
1191     AV_PIX_FMT_YUV420P,
1192     AV_PIX_FMT_NONE
1193 };
1194
1195 static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1196 #if CONFIG_MPEG2_XVMC_HWACCEL
1197     AV_PIX_FMT_XVMC,
1198 #endif
1199 #if CONFIG_MPEG_VDPAU_DECODER && FF_API_VDPAU
1200     AV_PIX_FMT_VDPAU_MPEG2,
1201 #endif
1202 #if CONFIG_MPEG2_VDPAU_HWACCEL
1203     AV_PIX_FMT_VDPAU,
1204 #endif
1205 #if CONFIG_MPEG2_DXVA2_HWACCEL
1206     AV_PIX_FMT_DXVA2_VLD,
1207 #endif
1208 #if CONFIG_MPEG2_D3D11VA_HWACCEL
1209     AV_PIX_FMT_D3D11VA_VLD,
1210 #endif
1211 #if CONFIG_MPEG2_VAAPI_HWACCEL
1212     AV_PIX_FMT_VAAPI,
1213 #endif
1214 #if CONFIG_MPEG2_VIDEOTOOLBOX_HWACCEL
1215     AV_PIX_FMT_VIDEOTOOLBOX,
1216 #endif
1217     AV_PIX_FMT_YUV420P,
1218     AV_PIX_FMT_NONE
1219 };
1220
1221 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1222     AV_PIX_FMT_YUV422P,
1223     AV_PIX_FMT_NONE
1224 };
1225
1226 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1227     AV_PIX_FMT_YUV444P,
1228     AV_PIX_FMT_NONE
1229 };
1230
1231 #if FF_API_VDPAU
1232 static inline int uses_vdpau(AVCodecContext *avctx) {
1233     return avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG1 || avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG2;
1234 }
1235 #endif
1236
1237 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1238 {
1239     Mpeg1Context *s1  = avctx->priv_data;
1240     MpegEncContext *s = &s1->mpeg_enc_ctx;
1241     const enum AVPixelFormat *pix_fmts;
1242
1243     if (CONFIG_GRAY && (avctx->flags & AV_CODEC_FLAG_GRAY))
1244         return AV_PIX_FMT_GRAY8;
1245
1246     if (s->chroma_format < 2)
1247         pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1248                                 mpeg1_hwaccel_pixfmt_list_420 :
1249                                 mpeg2_hwaccel_pixfmt_list_420;
1250     else if (s->chroma_format == 2)
1251         pix_fmts = mpeg12_pixfmt_list_422;
1252     else
1253         pix_fmts = mpeg12_pixfmt_list_444;
1254
1255     return ff_thread_get_format(avctx, pix_fmts);
1256 }
1257
1258 static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
1259 {
1260     // until then pix_fmt may be changed right after codec init
1261     if (avctx->hwaccel
1262 #if FF_API_VDPAU
1263         || uses_vdpau(avctx)
1264 #endif
1265         )
1266         if (avctx->idct_algo == FF_IDCT_AUTO)
1267             avctx->idct_algo = FF_IDCT_SIMPLE;
1268
1269     if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
1270         Mpeg1Context *s1 = avctx->priv_data;
1271         MpegEncContext *s = &s1->mpeg_enc_ctx;
1272
1273         s->pack_pblocks = 1;
1274 #if FF_API_XVMC
1275 FF_DISABLE_DEPRECATION_WARNINGS
1276         avctx->xvmc_acceleration = 2;
1277 FF_ENABLE_DEPRECATION_WARNINGS
1278 #endif /* FF_API_XVMC */
1279     }
1280 }
1281
1282 /* Call this function when we know all parameters.
1283  * It may be called in different places for MPEG-1 and MPEG-2. */
1284 static int mpeg_decode_postinit(AVCodecContext *avctx)
1285 {
1286     Mpeg1Context *s1  = avctx->priv_data;
1287     MpegEncContext *s = &s1->mpeg_enc_ctx;
1288     uint8_t old_permutation[64];
1289     int ret;
1290
1291     if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1292         // MPEG-1 aspect
1293         avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1294     } else { // MPEG-2
1295         // MPEG-2 aspect
1296         if (s->aspect_ratio_info > 1) {
1297             AVRational dar =
1298                 av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1299                                   (AVRational) { s1->pan_scan.width,
1300                                                  s1->pan_scan.height }),
1301                          (AVRational) { s->width, s->height });
1302
1303             /* We ignore the spec here and guess a bit as reality does not
1304              * match the spec, see for example res_change_ffmpeg_aspect.ts
1305              * and sequence-display-aspect.mpg.
1306              * issue1613, 621, 562 */
1307             if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1308                 (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1309                  av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1310                 s->avctx->sample_aspect_ratio =
1311                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1312                              (AVRational) { s->width, s->height });
1313             } else {
1314                 s->avctx->sample_aspect_ratio =
1315                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1316                              (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1317 // issue1613 4/3 16/9 -> 16/9
1318 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1319 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1320 //                s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1321                 ff_dlog(avctx, "aspect A %d/%d\n",
1322                         ff_mpeg2_aspect[s->aspect_ratio_info].num,
1323                         ff_mpeg2_aspect[s->aspect_ratio_info].den);
1324                 ff_dlog(avctx, "aspect B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1325                         s->avctx->sample_aspect_ratio.den);
1326             }
1327         } else {
1328             s->avctx->sample_aspect_ratio =
1329                 ff_mpeg2_aspect[s->aspect_ratio_info];
1330         }
1331     } // MPEG-2
1332
1333     if (av_image_check_sar(s->width, s->height,
1334                            avctx->sample_aspect_ratio) < 0) {
1335         av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
1336                 avctx->sample_aspect_ratio.num,
1337                 avctx->sample_aspect_ratio.den);
1338         avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
1339     }
1340
1341     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1342         avctx->coded_width       != s->width                ||
1343         avctx->coded_height      != s->height               ||
1344         s1->save_width           != s->width                ||
1345         s1->save_height          != s->height               ||
1346         av_cmp_q(s1->save_aspect, s->avctx->sample_aspect_ratio) ||
1347         (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1348         0) {
1349         if (s1->mpeg_enc_ctx_allocated) {
1350             ParseContext pc = s->parse_context;
1351             s->parse_context.buffer = 0;
1352             ff_mpv_common_end(s);
1353             s->parse_context = pc;
1354             s1->mpeg_enc_ctx_allocated = 0;
1355         }
1356
1357         ret = ff_set_dimensions(avctx, s->width, s->height);
1358         if (ret < 0)
1359             return ret;
1360
1361         if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
1362             avctx->rc_max_rate = s->bit_rate;
1363         } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
1364                    (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
1365             avctx->bit_rate = s->bit_rate;
1366         }
1367         s1->save_aspect          = s->avctx->sample_aspect_ratio;
1368         s1->save_width           = s->width;
1369         s1->save_height          = s->height;
1370         s1->save_progressive_seq = s->progressive_sequence;
1371
1372         /* low_delay may be forced, in this case we will have B-frames
1373          * that behave like P-frames. */
1374         avctx->has_b_frames = !s->low_delay;
1375
1376         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1377             // MPEG-1 fps
1378             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1379             avctx->ticks_per_frame     = 1;
1380
1381             avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1382         } else { // MPEG-2
1383             // MPEG-2 fps
1384             av_reduce(&s->avctx->framerate.num,
1385                       &s->avctx->framerate.den,
1386                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1387                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1388                       1 << 30);
1389             avctx->ticks_per_frame = 2;
1390
1391             switch (s->chroma_format) {
1392             case 1: avctx->chroma_sample_location = AVCHROMA_LOC_LEFT; break;
1393             case 2:
1394             case 3: avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT; break;
1395             default: av_assert0(0);
1396             }
1397         } // MPEG-2
1398
1399         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1400         setup_hwaccel_for_pixfmt(avctx);
1401
1402         /* Quantization matrices may need reordering
1403          * if DCT permutation is changed. */
1404         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1405
1406         ff_mpv_idct_init(s);
1407         if ((ret = ff_mpv_common_init(s)) < 0)
1408             return ret;
1409
1410         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1411         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1412         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1413         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1414
1415         s1->mpeg_enc_ctx_allocated = 1;
1416     }
1417     return 0;
1418 }
1419
1420 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1421                                 int buf_size)
1422 {
1423     Mpeg1Context *s1  = avctx->priv_data;
1424     MpegEncContext *s = &s1->mpeg_enc_ctx;
1425     int ref, f_code, vbv_delay;
1426
1427     init_get_bits(&s->gb, buf, buf_size * 8);
1428
1429     ref = get_bits(&s->gb, 10); /* temporal ref */
1430     s->pict_type = get_bits(&s->gb, 3);
1431     if (s->pict_type == 0 || s->pict_type > 3)
1432         return AVERROR_INVALIDDATA;
1433
1434     vbv_delay = get_bits(&s->gb, 16);
1435     s->vbv_delay = vbv_delay;
1436     if (s->pict_type == AV_PICTURE_TYPE_P ||
1437         s->pict_type == AV_PICTURE_TYPE_B) {
1438         s->full_pel[0] = get_bits1(&s->gb);
1439         f_code = get_bits(&s->gb, 3);
1440         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1441             return AVERROR_INVALIDDATA;
1442         f_code += !f_code;
1443         s->mpeg_f_code[0][0] = f_code;
1444         s->mpeg_f_code[0][1] = f_code;
1445     }
1446     if (s->pict_type == AV_PICTURE_TYPE_B) {
1447         s->full_pel[1] = get_bits1(&s->gb);
1448         f_code = get_bits(&s->gb, 3);
1449         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1450             return AVERROR_INVALIDDATA;
1451         f_code += !f_code;
1452         s->mpeg_f_code[1][0] = f_code;
1453         s->mpeg_f_code[1][1] = f_code;
1454     }
1455     s->current_picture.f->pict_type = s->pict_type;
1456     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1457
1458     if (avctx->debug & FF_DEBUG_PICT_INFO)
1459         av_log(avctx, AV_LOG_DEBUG,
1460                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1461
1462     s->y_dc_scale = 8;
1463     s->c_dc_scale = 8;
1464     return 0;
1465 }
1466
1467 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1468 {
1469     MpegEncContext *s = &s1->mpeg_enc_ctx;
1470     int horiz_size_ext, vert_size_ext;
1471     int bit_rate_ext;
1472
1473     skip_bits(&s->gb, 1); /* profile and level esc*/
1474     s->avctx->profile       = get_bits(&s->gb, 3);
1475     s->avctx->level         = get_bits(&s->gb, 4);
1476     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1477     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1478
1479     if (!s->chroma_format) {
1480         s->chroma_format = 1;
1481         av_log(s->avctx, AV_LOG_WARNING, "Chroma format invalid\n");
1482     }
1483
1484     horiz_size_ext          = get_bits(&s->gb, 2);
1485     vert_size_ext           = get_bits(&s->gb, 2);
1486     s->width  |= (horiz_size_ext << 12);
1487     s->height |= (vert_size_ext  << 12);
1488     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1489     s->bit_rate += (bit_rate_ext << 18) * 400LL;
1490     check_marker(&s->gb, "after bit rate extension");
1491     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1492
1493     s->low_delay = get_bits1(&s->gb);
1494     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
1495         s->low_delay = 1;
1496
1497     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1498     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1499
1500     ff_dlog(s->avctx, "sequence extension\n");
1501     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1502
1503     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1504         av_log(s->avctx, AV_LOG_DEBUG,
1505                "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%"PRId64"\n",
1506                s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1507                s->avctx->rc_buffer_size, s->bit_rate);
1508 }
1509
1510 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1511 {
1512     MpegEncContext *s = &s1->mpeg_enc_ctx;
1513     int color_description, w, h;
1514
1515     skip_bits(&s->gb, 3); /* video format */
1516     color_description = get_bits1(&s->gb);
1517     if (color_description) {
1518         s->avctx->color_primaries = get_bits(&s->gb, 8);
1519         s->avctx->color_trc       = get_bits(&s->gb, 8);
1520         s->avctx->colorspace      = get_bits(&s->gb, 8);
1521     }
1522     w = get_bits(&s->gb, 14);
1523     skip_bits(&s->gb, 1); // marker
1524     h = get_bits(&s->gb, 14);
1525     // remaining 3 bits are zero padding
1526
1527     s1->pan_scan.width  = 16 * w;
1528     s1->pan_scan.height = 16 * h;
1529
1530     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1531         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1532 }
1533
1534 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1535 {
1536     MpegEncContext *s = &s1->mpeg_enc_ctx;
1537     int i, nofco;
1538
1539     nofco = 1;
1540     if (s->progressive_sequence) {
1541         if (s->repeat_first_field) {
1542             nofco++;
1543             if (s->top_field_first)
1544                 nofco++;
1545         }
1546     } else {
1547         if (s->picture_structure == PICT_FRAME) {
1548             nofco++;
1549             if (s->repeat_first_field)
1550                 nofco++;
1551         }
1552     }
1553     for (i = 0; i < nofco; i++) {
1554         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1555         skip_bits(&s->gb, 1); // marker
1556         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1557         skip_bits(&s->gb, 1); // marker
1558     }
1559
1560     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1561         av_log(s->avctx, AV_LOG_DEBUG,
1562                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1563                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1564                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1565                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1566 }
1567
1568 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1569                        uint16_t matrix1[64], int intra)
1570 {
1571     int i;
1572
1573     for (i = 0; i < 64; i++) {
1574         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1575         int v = get_bits(&s->gb, 8);
1576         if (v == 0) {
1577             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1578             return AVERROR_INVALIDDATA;
1579         }
1580         if (intra && i == 0 && v != 8) {
1581             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1582             v = 8; // needed by pink.mpg / issue1046
1583         }
1584         matrix0[j] = v;
1585         if (matrix1)
1586             matrix1[j] = v;
1587     }
1588     return 0;
1589 }
1590
1591 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1592 {
1593     ff_dlog(s->avctx, "matrix extension\n");
1594
1595     if (get_bits1(&s->gb))
1596         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1597     if (get_bits1(&s->gb))
1598         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1599     if (get_bits1(&s->gb))
1600         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1601     if (get_bits1(&s->gb))
1602         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1603 }
1604
1605 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1606 {
1607     MpegEncContext *s = &s1->mpeg_enc_ctx;
1608
1609     s->full_pel[0]       = s->full_pel[1] = 0;
1610     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1611     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1612     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1613     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1614     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1615         av_log(s->avctx, AV_LOG_ERROR,
1616                "Missing picture start code, guessing missing values\n");
1617         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1618             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1619                 s->pict_type = AV_PICTURE_TYPE_I;
1620             else
1621                 s->pict_type = AV_PICTURE_TYPE_P;
1622         } else
1623             s->pict_type = AV_PICTURE_TYPE_B;
1624         s->current_picture.f->pict_type = s->pict_type;
1625         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1626     }
1627     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1628     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1629     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1630     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1631
1632     s->intra_dc_precision         = get_bits(&s->gb, 2);
1633     s->picture_structure          = get_bits(&s->gb, 2);
1634     s->top_field_first            = get_bits1(&s->gb);
1635     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1636     s->concealment_motion_vectors = get_bits1(&s->gb);
1637     s->q_scale_type               = get_bits1(&s->gb);
1638     s->intra_vlc_format           = get_bits1(&s->gb);
1639     s->alternate_scan             = get_bits1(&s->gb);
1640     s->repeat_first_field         = get_bits1(&s->gb);
1641     s->chroma_420_type            = get_bits1(&s->gb);
1642     s->progressive_frame          = get_bits1(&s->gb);
1643
1644     if (s->alternate_scan) {
1645         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1646         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1647     } else {
1648         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1649         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1650     }
1651
1652     /* composite display not parsed */
1653     ff_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1654     ff_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1655     ff_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1656     ff_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1657     ff_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1658     ff_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1659     ff_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1660     ff_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1661     ff_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1662 }
1663
1664 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1665 {
1666     AVCodecContext *avctx = s->avctx;
1667     Mpeg1Context *s1      = (Mpeg1Context *) s;
1668     int ret;
1669
1670     /* start frame decoding */
1671     if (s->first_field || s->picture_structure == PICT_FRAME) {
1672         AVFrameSideData *pan_scan;
1673
1674         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1675             return ret;
1676
1677         ff_mpeg_er_frame_start(s);
1678
1679         /* first check if we must repeat the frame */
1680         s->current_picture_ptr->f->repeat_pict = 0;
1681         if (s->repeat_first_field) {
1682             if (s->progressive_sequence) {
1683                 if (s->top_field_first)
1684                     s->current_picture_ptr->f->repeat_pict = 4;
1685                 else
1686                     s->current_picture_ptr->f->repeat_pict = 2;
1687             } else if (s->progressive_frame) {
1688                 s->current_picture_ptr->f->repeat_pict = 1;
1689             }
1690         }
1691
1692         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1693                                           AV_FRAME_DATA_PANSCAN,
1694                                           sizeof(s1->pan_scan));
1695         if (!pan_scan)
1696             return AVERROR(ENOMEM);
1697         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1698
1699         if (s1->a53_caption) {
1700             AVFrameSideData *sd = av_frame_new_side_data(
1701                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1702                 s1->a53_caption_size);
1703             if (sd)
1704                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1705             av_freep(&s1->a53_caption);
1706             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
1707         }
1708
1709         if (s1->has_stereo3d) {
1710             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1711             if (!stereo)
1712                 return AVERROR(ENOMEM);
1713
1714             *stereo = s1->stereo3d;
1715             s1->has_stereo3d = 0;
1716         }
1717
1718         if (s1->has_afd) {
1719             AVFrameSideData *sd =
1720                 av_frame_new_side_data(s->current_picture_ptr->f,
1721                                        AV_FRAME_DATA_AFD, 1);
1722             if (!sd)
1723                 return AVERROR(ENOMEM);
1724
1725             *sd->data   = s1->afd;
1726             s1->has_afd = 0;
1727         }
1728
1729         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1730             ff_thread_finish_setup(avctx);
1731     } else { // second field
1732         int i;
1733
1734         if (!s->current_picture_ptr) {
1735             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1736             return AVERROR_INVALIDDATA;
1737         }
1738
1739         if (s->avctx->hwaccel &&
1740             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1741             if ((ret = s->avctx->hwaccel->end_frame(s->avctx)) < 0) {
1742                 av_log(avctx, AV_LOG_ERROR,
1743                        "hardware accelerator failed to decode first field\n");
1744                 return ret;
1745             }
1746         }
1747
1748         for (i = 0; i < 4; i++) {
1749             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1750             if (s->picture_structure == PICT_BOTTOM_FIELD)
1751                 s->current_picture.f->data[i] +=
1752                     s->current_picture_ptr->f->linesize[i];
1753         }
1754     }
1755
1756     if (avctx->hwaccel) {
1757         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1758             return ret;
1759     }
1760
1761     return 0;
1762 }
1763
1764 #define DECODE_SLICE_ERROR -1
1765 #define DECODE_SLICE_OK     0
1766
1767 /**
1768  * Decode a slice.
1769  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1770  * @return DECODE_SLICE_ERROR if the slice is damaged,
1771  *         DECODE_SLICE_OK if this slice is OK
1772  */
1773 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1774                              const uint8_t **buf, int buf_size)
1775 {
1776     AVCodecContext *avctx = s->avctx;
1777     const int lowres      = s->avctx->lowres;
1778     const int field_pic   = s->picture_structure != PICT_FRAME;
1779     int ret;
1780
1781     s->resync_mb_x =
1782     s->resync_mb_y = -1;
1783
1784     av_assert0(mb_y < s->mb_height);
1785
1786     init_get_bits(&s->gb, *buf, buf_size * 8);
1787     if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1788         skip_bits(&s->gb, 3);
1789
1790     ff_mpeg1_clean_buffers(s);
1791     s->interlaced_dct = 0;
1792
1793     s->qscale = get_qscale(s);
1794
1795     if (s->qscale == 0) {
1796         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1797         return AVERROR_INVALIDDATA;
1798     }
1799
1800     /* extra slice info */
1801     if (skip_1stop_8data_bits(&s->gb) < 0)
1802         return AVERROR_INVALIDDATA;
1803
1804     s->mb_x = 0;
1805
1806     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1807         skip_bits1(&s->gb);
1808     } else {
1809         while (get_bits_left(&s->gb) > 0) {
1810             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1811                                 MBINCR_VLC_BITS, 2);
1812             if (code < 0) {
1813                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1814                 return AVERROR_INVALIDDATA;
1815             }
1816             if (code >= 33) {
1817                 if (code == 33)
1818                     s->mb_x += 33;
1819                 /* otherwise, stuffing, nothing to do */
1820             } else {
1821                 s->mb_x += code;
1822                 break;
1823             }
1824         }
1825     }
1826
1827     if (s->mb_x >= (unsigned) s->mb_width) {
1828         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1829         return AVERROR_INVALIDDATA;
1830     }
1831
1832     if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1833         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1834         int start_code = -1;
1835         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1836         if (buf_end < *buf + buf_size)
1837             buf_end -= 4;
1838         s->mb_y = mb_y;
1839         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1840             return DECODE_SLICE_ERROR;
1841         *buf = buf_end;
1842         return DECODE_SLICE_OK;
1843     }
1844
1845     s->resync_mb_x = s->mb_x;
1846     s->resync_mb_y = s->mb_y = mb_y;
1847     s->mb_skip_run = 0;
1848     ff_init_block_index(s);
1849
1850     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1851         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1852             av_log(s->avctx, AV_LOG_DEBUG,
1853                    "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",
1854                    s->qscale,
1855                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1856                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1857                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1858                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1859                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1860                    s->progressive_sequence ? "ps"  : "",
1861                    s->progressive_frame    ? "pf"  : "",
1862                    s->alternate_scan       ? "alt" : "",
1863                    s->top_field_first      ? "top" : "",
1864                    s->intra_dc_precision, s->picture_structure,
1865                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1866                    s->q_scale_type, s->intra_vlc_format,
1867                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1868         }
1869     }
1870
1871     for (;;) {
1872         // If 1, we memcpy blocks in xvmcvideo.
1873         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1874             ff_xvmc_init_block(s); // set s->block
1875
1876         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1877             return ret;
1878
1879         // Note motion_val is normally NULL unless we want to extract the MVs.
1880         if (s->current_picture.motion_val[0] && !s->encoding) {
1881             const int wrap = s->b8_stride;
1882             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1883             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1884             int motion_x, motion_y, dir, i;
1885
1886             for (i = 0; i < 2; i++) {
1887                 for (dir = 0; dir < 2; dir++) {
1888                     if (s->mb_intra ||
1889                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1890                         motion_x = motion_y = 0;
1891                     } else if (s->mv_type == MV_TYPE_16X16 ||
1892                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1893                         motion_x = s->mv[dir][0][0];
1894                         motion_y = s->mv[dir][0][1];
1895                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1896                         motion_x = s->mv[dir][i][0];
1897                         motion_y = s->mv[dir][i][1];
1898                     }
1899
1900                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1901                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1902                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1903                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1904                     s->current_picture.ref_index [dir][b8_xy]     =
1905                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1906                     av_assert2(s->field_select[dir][i] == 0 ||
1907                                s->field_select[dir][i] == 1);
1908                 }
1909                 xy    += wrap;
1910                 b8_xy += 2;
1911             }
1912         }
1913
1914         s->dest[0] += 16 >> lowres;
1915         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1916         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1917
1918         ff_mpv_decode_mb(s, s->block);
1919
1920         if (++s->mb_x >= s->mb_width) {
1921             const int mb_size = 16 >> s->avctx->lowres;
1922
1923             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1924             ff_mpv_report_decode_progress(s);
1925
1926             s->mb_x  = 0;
1927             s->mb_y += 1 << field_pic;
1928
1929             if (s->mb_y >= s->mb_height) {
1930                 int left   = get_bits_left(&s->gb);
1931                 int is_d10 = s->chroma_format == 2 &&
1932                              s->pict_type == AV_PICTURE_TYPE_I &&
1933                              avctx->profile == 0 && avctx->level == 5 &&
1934                              s->intra_dc_precision == 2 &&
1935                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1936                              s->progressive_frame == 0
1937                              /* vbv_delay == 0xBBB || 0xE10 */;
1938
1939                 if (left >= 32 && !is_d10) {
1940                     GetBitContext gb = s->gb;
1941                     align_get_bits(&gb);
1942                     if (show_bits(&gb, 24) == 0x060E2B) {
1943                         av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
1944                         is_d10 = 1;
1945                     }
1946                 }
1947
1948                 if (left < 0 ||
1949                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1950                     ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1951                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1952                            left, show_bits(&s->gb, FFMIN(left, 23)));
1953                     return AVERROR_INVALIDDATA;
1954                 } else
1955                     goto eos;
1956             }
1957             // There are some files out there which are missing the last slice
1958             // in cases where the slice is completely outside the visible
1959             // area, we detect this here instead of running into the end expecting
1960             // more data
1961             if (s->mb_y >= ((s->height + 15) >> 4) &&
1962                 !s->progressive_sequence &&
1963                 get_bits_left(&s->gb) <= 8 &&
1964                 get_bits_left(&s->gb) >= 0 &&
1965                 s->mb_skip_run == -1 &&
1966                 show_bits(&s->gb, 8) == 0)
1967                 goto eos;
1968
1969             ff_init_block_index(s);
1970         }
1971
1972         /* skip mb handling */
1973         if (s->mb_skip_run == -1) {
1974             /* read increment again */
1975             s->mb_skip_run = 0;
1976             for (;;) {
1977                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1978                                     MBINCR_VLC_BITS, 2);
1979                 if (code < 0) {
1980                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1981                     return AVERROR_INVALIDDATA;
1982                 }
1983                 if (code >= 33) {
1984                     if (code == 33) {
1985                         s->mb_skip_run += 33;
1986                     } else if (code == 35) {
1987                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1988                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1989                             return AVERROR_INVALIDDATA;
1990                         }
1991                         goto eos; /* end of slice */
1992                     }
1993                     /* otherwise, stuffing, nothing to do */
1994                 } else {
1995                     s->mb_skip_run += code;
1996                     break;
1997                 }
1998             }
1999             if (s->mb_skip_run) {
2000                 int i;
2001                 if (s->pict_type == AV_PICTURE_TYPE_I) {
2002                     av_log(s->avctx, AV_LOG_ERROR,
2003                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
2004                     return AVERROR_INVALIDDATA;
2005                 }
2006
2007                 /* skip mb */
2008                 s->mb_intra = 0;
2009                 for (i = 0; i < 12; i++)
2010                     s->block_last_index[i] = -1;
2011                 if (s->picture_structure == PICT_FRAME)
2012                     s->mv_type = MV_TYPE_16X16;
2013                 else
2014                     s->mv_type = MV_TYPE_FIELD;
2015                 if (s->pict_type == AV_PICTURE_TYPE_P) {
2016                     /* if P type, zero motion vector is implied */
2017                     s->mv_dir             = MV_DIR_FORWARD;
2018                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
2019                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
2020                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
2021                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
2022                 } else {
2023                     /* if B type, reuse previous vectors and directions */
2024                     s->mv[0][0][0] = s->last_mv[0][0][0];
2025                     s->mv[0][0][1] = s->last_mv[0][0][1];
2026                     s->mv[1][0][0] = s->last_mv[1][0][0];
2027                     s->mv[1][0][1] = s->last_mv[1][0][1];
2028                 }
2029             }
2030         }
2031     }
2032 eos: // end of slice
2033     if (get_bits_left(&s->gb) < 0) {
2034         av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
2035         return AVERROR_INVALIDDATA;
2036     }
2037     *buf += (get_bits_count(&s->gb) - 1) / 8;
2038     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);
2039     return 0;
2040 }
2041
2042 static int slice_decode_thread(AVCodecContext *c, void *arg)
2043 {
2044     MpegEncContext *s   = *(void **) arg;
2045     const uint8_t *buf  = s->gb.buffer;
2046     int mb_y            = s->start_mb_y;
2047     const int field_pic = s->picture_structure != PICT_FRAME;
2048
2049     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
2050
2051     for (;;) {
2052         uint32_t start_code;
2053         int ret;
2054
2055         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
2056         emms_c();
2057         ff_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2058                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
2059                 s->start_mb_y, s->end_mb_y, s->er.error_count);
2060         if (ret < 0) {
2061             if (c->err_recognition & AV_EF_EXPLODE)
2062                 return ret;
2063             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
2064                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2065                                 s->mb_x, s->mb_y,
2066                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2067         } else {
2068             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2069                             s->mb_x - 1, s->mb_y,
2070                             ER_AC_END | ER_DC_END | ER_MV_END);
2071         }
2072
2073         if (s->mb_y == s->end_mb_y)
2074             return 0;
2075
2076         start_code = -1;
2077         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2078         mb_y       = start_code - SLICE_MIN_START_CODE;
2079         if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2080             mb_y += (*buf&0xE0)<<2;
2081         mb_y <<= field_pic;
2082         if (s->picture_structure == PICT_BOTTOM_FIELD)
2083             mb_y++;
2084         if (mb_y < 0 || mb_y >= s->end_mb_y)
2085             return AVERROR_INVALIDDATA;
2086     }
2087 }
2088
2089 /**
2090  * Handle slice ends.
2091  * @return 1 if it seems to be the last slice
2092  */
2093 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2094 {
2095     Mpeg1Context *s1  = avctx->priv_data;
2096     MpegEncContext *s = &s1->mpeg_enc_ctx;
2097
2098     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2099         return 0;
2100
2101     if (s->avctx->hwaccel) {
2102         int ret = s->avctx->hwaccel->end_frame(s->avctx);
2103         if (ret < 0) {
2104             av_log(avctx, AV_LOG_ERROR,
2105                    "hardware accelerator failed to decode picture\n");
2106             return ret;
2107         }
2108     }
2109
2110     /* end of slice reached */
2111     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
2112         /* end of image */
2113
2114         ff_er_frame_end(&s->er);
2115
2116         ff_mpv_frame_end(s);
2117
2118         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2119             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2120             if (ret < 0)
2121                 return ret;
2122             ff_print_debug_info(s, s->current_picture_ptr, pict);
2123             ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2124         } else {
2125             if (avctx->active_thread_type & FF_THREAD_FRAME)
2126                 s->picture_number++;
2127             /* latency of 1 frame for I- and P-frames */
2128             /* XXX: use another variable than picture_number */
2129             if (s->last_picture_ptr) {
2130                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2131                 if (ret < 0)
2132                     return ret;
2133                 ff_print_debug_info(s, s->last_picture_ptr, pict);
2134                 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2135             }
2136         }
2137
2138         return 1;
2139     } else {
2140         return 0;
2141     }
2142 }
2143
2144 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2145                                  const uint8_t *buf, int buf_size)
2146 {
2147     Mpeg1Context *s1  = avctx->priv_data;
2148     MpegEncContext *s = &s1->mpeg_enc_ctx;
2149     int width, height;
2150     int i, v, j;
2151
2152     init_get_bits(&s->gb, buf, buf_size * 8);
2153
2154     width  = get_bits(&s->gb, 12);
2155     height = get_bits(&s->gb, 12);
2156     if (width == 0 || height == 0) {
2157         av_log(avctx, AV_LOG_WARNING,
2158                "Invalid horizontal or vertical size value.\n");
2159         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2160             return AVERROR_INVALIDDATA;
2161     }
2162     s->aspect_ratio_info = get_bits(&s->gb, 4);
2163     if (s->aspect_ratio_info == 0) {
2164         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2165         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2166             return AVERROR_INVALIDDATA;
2167     }
2168     s->frame_rate_index = get_bits(&s->gb, 4);
2169     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2170         av_log(avctx, AV_LOG_WARNING,
2171                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2172         s->frame_rate_index = 1;
2173     }
2174     s->bit_rate = get_bits(&s->gb, 18) * 400LL;
2175     if (check_marker(&s->gb, "in sequence header") == 0) {
2176         return AVERROR_INVALIDDATA;
2177     }
2178
2179     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2180     skip_bits(&s->gb, 1);
2181
2182     /* get matrix */
2183     if (get_bits1(&s->gb)) {
2184         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2185     } else {
2186         for (i = 0; i < 64; i++) {
2187             j = s->idsp.idct_permutation[i];
2188             v = ff_mpeg1_default_intra_matrix[i];
2189             s->intra_matrix[j]        = v;
2190             s->chroma_intra_matrix[j] = v;
2191         }
2192     }
2193     if (get_bits1(&s->gb)) {
2194         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2195     } else {
2196         for (i = 0; i < 64; i++) {
2197             int j = s->idsp.idct_permutation[i];
2198             v = ff_mpeg1_default_non_intra_matrix[i];
2199             s->inter_matrix[j]        = v;
2200             s->chroma_inter_matrix[j] = v;
2201         }
2202     }
2203
2204     if (show_bits(&s->gb, 23) != 0) {
2205         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2206         return AVERROR_INVALIDDATA;
2207     }
2208
2209     s->width  = width;
2210     s->height = height;
2211
2212     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2213     s->progressive_sequence = 1;
2214     s->progressive_frame    = 1;
2215     s->picture_structure    = PICT_FRAME;
2216     s->first_field          = 0;
2217     s->frame_pred_frame_dct = 1;
2218     s->chroma_format        = 1;
2219     s->codec_id             =
2220     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2221     s->out_format           = FMT_MPEG1;
2222     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2223     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
2224         s->low_delay = 1;
2225
2226     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2227         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%"PRId64", aspect_ratio_info: %d \n",
2228                s->avctx->rc_buffer_size, s->bit_rate, s->aspect_ratio_info);
2229
2230     return 0;
2231 }
2232
2233 static int vcr2_init_sequence(AVCodecContext *avctx)
2234 {
2235     Mpeg1Context *s1  = avctx->priv_data;
2236     MpegEncContext *s = &s1->mpeg_enc_ctx;
2237     int i, v, ret;
2238
2239     /* start new MPEG-1 context decoding */
2240     s->out_format = FMT_MPEG1;
2241     if (s1->mpeg_enc_ctx_allocated) {
2242         ff_mpv_common_end(s);
2243         s1->mpeg_enc_ctx_allocated = 0;
2244     }
2245     s->width            = avctx->coded_width;
2246     s->height           = avctx->coded_height;
2247     avctx->has_b_frames = 0; // true?
2248     s->low_delay        = 1;
2249
2250     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2251     setup_hwaccel_for_pixfmt(avctx);
2252
2253     ff_mpv_idct_init(s);
2254     if ((ret = ff_mpv_common_init(s)) < 0)
2255         return ret;
2256     s1->mpeg_enc_ctx_allocated = 1;
2257
2258     for (i = 0; i < 64; i++) {
2259         int j = s->idsp.idct_permutation[i];
2260         v = ff_mpeg1_default_intra_matrix[i];
2261         s->intra_matrix[j]        = v;
2262         s->chroma_intra_matrix[j] = v;
2263
2264         v = ff_mpeg1_default_non_intra_matrix[i];
2265         s->inter_matrix[j]        = v;
2266         s->chroma_inter_matrix[j] = v;
2267     }
2268
2269     s->progressive_sequence  = 1;
2270     s->progressive_frame     = 1;
2271     s->picture_structure     = PICT_FRAME;
2272     s->first_field           = 0;
2273     s->frame_pred_frame_dct  = 1;
2274     s->chroma_format         = 1;
2275     if (s->codec_tag == AV_RL32("BW10")) {
2276         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2277     } else {
2278         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2279         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2280     }
2281     s1->save_width           = s->width;
2282     s1->save_height          = s->height;
2283     s1->save_progressive_seq = s->progressive_sequence;
2284     return 0;
2285 }
2286
2287 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2288                               const uint8_t *p, int buf_size)
2289 {
2290     Mpeg1Context *s1 = avctx->priv_data;
2291
2292     if (buf_size >= 6 &&
2293         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2294         p[4] == 3 && (p[5] & 0x40)) {
2295         /* extract A53 Part 4 CC data */
2296         int cc_count = p[5] & 0x1f;
2297         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2298             av_freep(&s1->a53_caption);
2299             s1->a53_caption_size = cc_count * 3;
2300             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2301             if (s1->a53_caption)
2302                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2303         }
2304         return 1;
2305     } else if (buf_size >= 11 &&
2306                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2307         /* extract DVD CC data */
2308         int cc_count = 0;
2309         int i;
2310         // There is a caption count field in the data, but it is often
2311         // incorect.  So count the number of captions present.
2312         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2313             cc_count++;
2314         // Transform the DVD format into A53 Part 4 format
2315         if (cc_count > 0) {
2316             av_freep(&s1->a53_caption);
2317             s1->a53_caption_size = cc_count * 6;
2318             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2319             if (s1->a53_caption) {
2320                 uint8_t field1 = !!(p[4] & 0x80);
2321                 uint8_t *cap = s1->a53_caption;
2322                 p += 5;
2323                 for (i = 0; i < cc_count; i++) {
2324                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2325                     cap[1] = p[1];
2326                     cap[2] = p[2];
2327                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2328                     cap[4] = p[4];
2329                     cap[5] = p[5];
2330                     cap += 6;
2331                     p += 6;
2332                 }
2333             }
2334         }
2335         return 1;
2336     }
2337     return 0;
2338 }
2339
2340 static void mpeg_decode_user_data(AVCodecContext *avctx,
2341                                   const uint8_t *p, int buf_size)
2342 {
2343     Mpeg1Context *s = avctx->priv_data;
2344     const uint8_t *buf_end = p + buf_size;
2345     Mpeg1Context *s1 = avctx->priv_data;
2346
2347 #if 0
2348     int i;
2349     for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2350         av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
2351     }
2352     av_log(avctx, AV_LOG_ERROR, "\n");
2353 #endif
2354
2355     if (buf_size > 29){
2356         int i;
2357         for(i=0; i<20; i++)
2358             if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2359                 s->tmpgexs= 1;
2360             }
2361     }
2362     /* we parse the DTG active format information */
2363     if (buf_end - p >= 5 &&
2364         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2365         int flags = p[4];
2366         p += 5;
2367         if (flags & 0x80) {
2368             /* skip event id */
2369             p += 2;
2370         }
2371         if (flags & 0x40) {
2372             if (buf_end - p < 1)
2373                 return;
2374 #if FF_API_AFD
2375 FF_DISABLE_DEPRECATION_WARNINGS
2376             avctx->dtg_active_format = p[0] & 0x0f;
2377 FF_ENABLE_DEPRECATION_WARNINGS
2378 #endif /* FF_API_AFD */
2379             s1->has_afd = 1;
2380             s1->afd     = p[0] & 0x0f;
2381         }
2382     } else if (buf_end - p >= 6 &&
2383                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2384                p[4] == 0x03) { // S3D_video_format_length
2385         // the 0x7F mask ignores the reserved_bit value
2386         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2387
2388         if (S3D_video_format_type == 0x03 ||
2389             S3D_video_format_type == 0x04 ||
2390             S3D_video_format_type == 0x08 ||
2391             S3D_video_format_type == 0x23) {
2392
2393             s1->has_stereo3d = 1;
2394
2395             switch (S3D_video_format_type) {
2396             case 0x03:
2397                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2398                 break;
2399             case 0x04:
2400                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2401                 break;
2402             case 0x08:
2403                 s1->stereo3d.type = AV_STEREO3D_2D;
2404                 break;
2405             case 0x23:
2406                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2407                 break;
2408             }
2409         }
2410     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2411         return;
2412     }
2413 }
2414
2415 static void mpeg_decode_gop(AVCodecContext *avctx,
2416                             const uint8_t *buf, int buf_size)
2417 {
2418     Mpeg1Context *s1  = avctx->priv_data;
2419     MpegEncContext *s = &s1->mpeg_enc_ctx;
2420     int broken_link;
2421     int64_t tc;
2422
2423     init_get_bits(&s->gb, buf, buf_size * 8);
2424
2425     tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2426
2427     s->closed_gop = get_bits1(&s->gb);
2428     /* broken_link indicate that after editing the
2429      * reference frames of the first B-Frames after GOP I-Frame
2430      * are missing (open gop) */
2431     broken_link = get_bits1(&s->gb);
2432
2433     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2434         char tcbuf[AV_TIMECODE_STR_SIZE];
2435         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2436         av_log(s->avctx, AV_LOG_DEBUG,
2437                "GOP (%s) closed_gop=%d broken_link=%d\n",
2438                tcbuf, s->closed_gop, broken_link);
2439     }
2440 }
2441
2442 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2443                          int *got_output, const uint8_t *buf, int buf_size)
2444 {
2445     Mpeg1Context *s = avctx->priv_data;
2446     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2447     const uint8_t *buf_ptr = buf;
2448     const uint8_t *buf_end = buf + buf_size;
2449     int ret, input_size;
2450     int last_code = 0, skip_frame = 0;
2451     int picture_start_code_seen = 0;
2452
2453     for (;;) {
2454         /* find next start code */
2455         uint32_t start_code = -1;
2456         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2457         if (start_code > 0x1ff) {
2458             if (!skip_frame) {
2459                 if (HAVE_THREADS &&
2460                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2461                     !avctx->hwaccel) {
2462                     int i;
2463                     av_assert0(avctx->thread_count > 1);
2464
2465                     avctx->execute(avctx, slice_decode_thread,
2466                                    &s2->thread_context[0], NULL,
2467                                    s->slice_count, sizeof(void *));
2468                     for (i = 0; i < s->slice_count; i++)
2469                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2470                 }
2471
2472 #if FF_API_VDPAU
2473                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2474                     && uses_vdpau(avctx))
2475                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2476 #endif
2477
2478                 ret = slice_end(avctx, picture);
2479                 if (ret < 0)
2480                     return ret;
2481                 else if (ret) {
2482                     // FIXME: merge with the stuff in mpeg_decode_slice
2483                     if (s2->last_picture_ptr || s2->low_delay)
2484                         *got_output = 1;
2485                 }
2486             }
2487             s2->pict_type = 0;
2488
2489             if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
2490                 return AVERROR_INVALIDDATA;
2491
2492             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2493         }
2494
2495         input_size = buf_end - buf_ptr;
2496
2497         if (avctx->debug & FF_DEBUG_STARTCODE)
2498             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2499                    start_code, buf_ptr - buf, input_size);
2500
2501         /* prepare data for next start code */
2502         switch (start_code) {
2503         case SEQ_START_CODE:
2504             if (last_code == 0) {
2505                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2506                 if (buf != avctx->extradata)
2507                     s->sync = 1;
2508             } else {
2509                 av_log(avctx, AV_LOG_ERROR,
2510                        "ignoring SEQ_START_CODE after %X\n", last_code);
2511                 if (avctx->err_recognition & AV_EF_EXPLODE)
2512                     return AVERROR_INVALIDDATA;
2513             }
2514             break;
2515
2516         case PICTURE_START_CODE:
2517             if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
2518                /* If it's a frame picture, there can't be more than one picture header.
2519                   Yet, it does happen and we need to handle it. */
2520                av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
2521                break;
2522             }
2523             picture_start_code_seen = 1;
2524
2525             if (s2->width <= 0 || s2->height <= 0) {
2526                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2527                        s2->width, s2->height);
2528                 return AVERROR_INVALIDDATA;
2529             }
2530
2531             if (s->tmpgexs){
2532                 s2->intra_dc_precision= 3;
2533                 s2->intra_matrix[0]= 1;
2534             }
2535             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2536                 !avctx->hwaccel && s->slice_count) {
2537                 int i;
2538
2539                 avctx->execute(avctx, slice_decode_thread,
2540                                s2->thread_context, NULL,
2541                                s->slice_count, sizeof(void *));
2542                 for (i = 0; i < s->slice_count; i++)
2543                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2544                 s->slice_count = 0;
2545             }
2546             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2547                 ret = mpeg_decode_postinit(avctx);
2548                 if (ret < 0) {
2549                     av_log(avctx, AV_LOG_ERROR,
2550                            "mpeg_decode_postinit() failure\n");
2551                     return ret;
2552                 }
2553
2554                 /* We have a complete image: we try to decompress it. */
2555                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2556                     s2->pict_type = 0;
2557                 s->first_slice = 1;
2558                 last_code      = PICTURE_START_CODE;
2559             } else {
2560                 av_log(avctx, AV_LOG_ERROR,
2561                        "ignoring pic after %X\n", last_code);
2562                 if (avctx->err_recognition & AV_EF_EXPLODE)
2563                     return AVERROR_INVALIDDATA;
2564             }
2565             break;
2566         case EXT_START_CODE:
2567             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2568
2569             switch (get_bits(&s2->gb, 4)) {
2570             case 0x1:
2571                 if (last_code == 0) {
2572                     mpeg_decode_sequence_extension(s);
2573                 } else {
2574                     av_log(avctx, AV_LOG_ERROR,
2575                            "ignoring seq ext after %X\n", last_code);
2576                     if (avctx->err_recognition & AV_EF_EXPLODE)
2577                         return AVERROR_INVALIDDATA;
2578                 }
2579                 break;
2580             case 0x2:
2581                 mpeg_decode_sequence_display_extension(s);
2582                 break;
2583             case 0x3:
2584                 mpeg_decode_quant_matrix_extension(s2);
2585                 break;
2586             case 0x7:
2587                 mpeg_decode_picture_display_extension(s);
2588                 break;
2589             case 0x8:
2590                 if (last_code == PICTURE_START_CODE) {
2591                     mpeg_decode_picture_coding_extension(s);
2592                 } else {
2593                     av_log(avctx, AV_LOG_ERROR,
2594                            "ignoring pic cod ext after %X\n", last_code);
2595                     if (avctx->err_recognition & AV_EF_EXPLODE)
2596                         return AVERROR_INVALIDDATA;
2597                 }
2598                 break;
2599             }
2600             break;
2601         case USER_START_CODE:
2602             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2603             break;
2604         case GOP_START_CODE:
2605             if (last_code == 0) {
2606                 s2->first_field = 0;
2607                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2608                 s->sync = 1;
2609             } else {
2610                 av_log(avctx, AV_LOG_ERROR,
2611                        "ignoring GOP_START_CODE after %X\n", last_code);
2612                 if (avctx->err_recognition & AV_EF_EXPLODE)
2613                     return AVERROR_INVALIDDATA;
2614             }
2615             break;
2616         default:
2617             if (start_code >= SLICE_MIN_START_CODE &&
2618                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2619                 if (s2->progressive_sequence && !s2->progressive_frame) {
2620                     s2->progressive_frame = 1;
2621                     av_log(s2->avctx, AV_LOG_ERROR,
2622                            "interlaced frame in progressive sequence, ignoring\n");
2623                 }
2624
2625                 if (s2->picture_structure == 0 ||
2626                     (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2627                     av_log(s2->avctx, AV_LOG_ERROR,
2628                            "picture_structure %d invalid, ignoring\n",
2629                            s2->picture_structure);
2630                     s2->picture_structure = PICT_FRAME;
2631                 }
2632
2633                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2634                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2635
2636                 if (s2->picture_structure == PICT_FRAME) {
2637                     s2->first_field = 0;
2638                     s2->v_edge_pos  = 16 * s2->mb_height;
2639                 } else {
2640                     s2->first_field ^= 1;
2641                     s2->v_edge_pos   = 8 * s2->mb_height;
2642                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2643                 }
2644             }
2645             if (start_code >= SLICE_MIN_START_CODE &&
2646                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2647                 const int field_pic = s2->picture_structure != PICT_FRAME;
2648                 int mb_y = start_code - SLICE_MIN_START_CODE;
2649                 last_code = SLICE_MIN_START_CODE;
2650                 if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2651                     mb_y += (*buf_ptr&0xE0)<<2;
2652
2653                 mb_y <<= field_pic;
2654                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2655                     mb_y++;
2656
2657                 if (buf_end - buf_ptr < 2) {
2658                     av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
2659                     return AVERROR_INVALIDDATA;
2660                 }
2661
2662                 if (mb_y >= s2->mb_height) {
2663                     av_log(s2->avctx, AV_LOG_ERROR,
2664                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2665                     return AVERROR_INVALIDDATA;
2666                 }
2667
2668                 if (!s2->last_picture_ptr) {
2669                     /* Skip B-frames if we do not have reference frames and
2670                      * GOP is not closed. */
2671                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2672                         if (!s2->closed_gop) {
2673                             skip_frame = 1;
2674                             break;
2675                         }
2676                     }
2677                 }
2678                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
2679                     s->sync = 1;
2680                 if (!s2->next_picture_ptr) {
2681                     /* Skip P-frames if we do not have a reference frame or
2682                      * we have an invalid header. */
2683                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2684                         skip_frame = 1;
2685                         break;
2686                     }
2687                 }
2688                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2689                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2690                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2691                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2692                     avctx->skip_frame >= AVDISCARD_ALL) {
2693                     skip_frame = 1;
2694                     break;
2695                 }
2696
2697                 if (!s->mpeg_enc_ctx_allocated)
2698                     break;
2699
2700                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2701                     if (mb_y < avctx->skip_top ||
2702                         mb_y >= s2->mb_height - avctx->skip_bottom)
2703                         break;
2704                 }
2705
2706                 if (!s2->pict_type) {
2707                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2708                     if (avctx->err_recognition & AV_EF_EXPLODE)
2709                         return AVERROR_INVALIDDATA;
2710                     break;
2711                 }
2712
2713                 if (s->first_slice) {
2714                     skip_frame     = 0;
2715                     s->first_slice = 0;
2716                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2717                         return ret;
2718                 }
2719                 if (!s2->current_picture_ptr) {
2720                     av_log(avctx, AV_LOG_ERROR,
2721                            "current_picture not initialized\n");
2722                     return AVERROR_INVALIDDATA;
2723                 }
2724
2725 #if FF_API_VDPAU
2726                 if (uses_vdpau(avctx)) {
2727                     s->slice_count++;
2728                     break;
2729                 }
2730 #endif
2731
2732                 if (HAVE_THREADS &&
2733                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2734                     !avctx->hwaccel) {
2735                     int threshold = (s2->mb_height * s->slice_count +
2736                                      s2->slice_context_count / 2) /
2737                                     s2->slice_context_count;
2738                     av_assert0(avctx->thread_count > 1);
2739                     if (threshold <= mb_y) {
2740                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2741
2742                         thread_context->start_mb_y = mb_y;
2743                         thread_context->end_mb_y   = s2->mb_height;
2744                         if (s->slice_count) {
2745                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2746                             ret = ff_update_duplicate_context(thread_context, s2);
2747                             if (ret < 0)
2748                                 return ret;
2749                         }
2750                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2751                         s->slice_count++;
2752                     }
2753                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2754                 } else {
2755                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2756                     emms_c();
2757
2758                     if (ret < 0) {
2759                         if (avctx->err_recognition & AV_EF_EXPLODE)
2760                             return ret;
2761                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2762                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2763                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2764                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2765                     } else {
2766                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2767                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2768                                         ER_AC_END | ER_DC_END | ER_MV_END);
2769                     }
2770                 }
2771             }
2772             break;
2773         }
2774     }
2775 }
2776
2777 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2778                              int *got_output, AVPacket *avpkt)
2779 {
2780     const uint8_t *buf = avpkt->data;
2781     int ret;
2782     int buf_size = avpkt->size;
2783     Mpeg1Context *s = avctx->priv_data;
2784     AVFrame *picture = data;
2785     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2786
2787     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2788         /* special case for last picture */
2789         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2790             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2791             if (ret < 0)
2792                 return ret;
2793
2794             s2->next_picture_ptr = NULL;
2795
2796             *got_output = 1;
2797         }
2798         return buf_size;
2799     }
2800
2801     if (s2->avctx->flags & AV_CODEC_FLAG_TRUNCATED) {
2802         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2803                                            buf_size, NULL);
2804
2805         if (ff_combine_frame(&s2->parse_context, next,
2806                              (const uint8_t **) &buf, &buf_size) < 0)
2807             return buf_size;
2808     }
2809
2810     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2811     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2812                                            || s2->codec_tag == AV_RL32("BW10")
2813                                           ))
2814         vcr2_init_sequence(avctx);
2815
2816     s->slice_count = 0;
2817
2818     if (avctx->extradata && !s->extradata_decoded) {
2819         ret = decode_chunks(avctx, picture, got_output,
2820                             avctx->extradata, avctx->extradata_size);
2821         if (*got_output) {
2822             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2823             *got_output = 0;
2824         }
2825         s->extradata_decoded = 1;
2826         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
2827             s2->current_picture_ptr = NULL;
2828             return ret;
2829         }
2830     }
2831
2832     ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
2833     if (ret<0 || *got_output)
2834         s2->current_picture_ptr = NULL;
2835
2836     return ret;
2837 }
2838
2839 static void flush(AVCodecContext *avctx)
2840 {
2841     Mpeg1Context *s = avctx->priv_data;
2842
2843     s->sync       = 0;
2844
2845     ff_mpeg_flush(avctx);
2846 }
2847
2848 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2849 {
2850     Mpeg1Context *s = avctx->priv_data;
2851
2852     if (s->mpeg_enc_ctx_allocated)
2853         ff_mpv_common_end(&s->mpeg_enc_ctx);
2854     av_freep(&s->a53_caption);
2855     return 0;
2856 }
2857
2858 static const AVProfile mpeg2_video_profiles[] = {
2859     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2860     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2861     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2862     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2863     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2864     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2865     { FF_PROFILE_RESERVED,           "Reserved"           },
2866     { FF_PROFILE_RESERVED,           "Reserved"           },
2867     { FF_PROFILE_UNKNOWN                                  },
2868 };
2869
2870 AVCodec ff_mpeg1video_decoder = {
2871     .name                  = "mpeg1video",
2872     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2873     .type                  = AVMEDIA_TYPE_VIDEO,
2874     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2875     .priv_data_size        = sizeof(Mpeg1Context),
2876     .init                  = mpeg_decode_init,
2877     .close                 = mpeg_decode_end,
2878     .decode                = mpeg_decode_frame,
2879     .capabilities          = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2880                              AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2881                              AV_CODEC_CAP_SLICE_THREADS,
2882     .flush                 = flush,
2883     .max_lowres            = 3,
2884     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2885 };
2886
2887 AVCodec ff_mpeg2video_decoder = {
2888     .name           = "mpeg2video",
2889     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2890     .type           = AVMEDIA_TYPE_VIDEO,
2891     .id             = AV_CODEC_ID_MPEG2VIDEO,
2892     .priv_data_size = sizeof(Mpeg1Context),
2893     .init           = mpeg_decode_init,
2894     .close          = mpeg_decode_end,
2895     .decode         = mpeg_decode_frame,
2896     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2897                       AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2898                       AV_CODEC_CAP_SLICE_THREADS,
2899     .flush          = flush,
2900     .max_lowres     = 3,
2901     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2902 };
2903
2904 //legacy decoder
2905 AVCodec ff_mpegvideo_decoder = {
2906     .name           = "mpegvideo",
2907     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2908     .type           = AVMEDIA_TYPE_VIDEO,
2909     .id             = AV_CODEC_ID_MPEG2VIDEO,
2910     .priv_data_size = sizeof(Mpeg1Context),
2911     .init           = mpeg_decode_init,
2912     .close          = mpeg_decode_end,
2913     .decode         = mpeg_decode_frame,
2914     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
2915     .flush          = flush,
2916     .max_lowres     = 3,
2917 };
2918
2919 #if FF_API_XVMC
2920 #if CONFIG_MPEG_XVMC_DECODER
2921 FF_DISABLE_DEPRECATION_WARNINGS
2922 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2923 {
2924     if (avctx->active_thread_type & FF_THREAD_SLICE)
2925         return -1;
2926     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2927         return -1;
2928     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2929         ff_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2930     }
2931     mpeg_decode_init(avctx);
2932
2933     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2934     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2935
2936     return 0;
2937 }
2938
2939 AVCodec ff_mpeg_xvmc_decoder = {
2940     .name           = "mpegvideo_xvmc",
2941     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2942     .type           = AVMEDIA_TYPE_VIDEO,
2943     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2944     .priv_data_size = sizeof(Mpeg1Context),
2945     .init           = mpeg_mc_decode_init,
2946     .close          = mpeg_decode_end,
2947     .decode         = mpeg_decode_frame,
2948     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2949                       AV_CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL |
2950                       AV_CODEC_CAP_DELAY,
2951     .flush          = flush,
2952 };
2953 FF_ENABLE_DEPRECATION_WARNINGS
2954 #endif
2955 #endif /* FF_API_XVMC */
2956
2957 #if CONFIG_MPEG_VDPAU_DECODER && FF_API_VDPAU
2958 AVCodec ff_mpeg_vdpau_decoder = {
2959     .name           = "mpegvideo_vdpau",
2960     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2961     .type           = AVMEDIA_TYPE_VIDEO,
2962     .id             = AV_CODEC_ID_MPEG2VIDEO,
2963     .priv_data_size = sizeof(Mpeg1Context),
2964     .init           = mpeg_decode_init,
2965     .close          = mpeg_decode_end,
2966     .decode         = mpeg_decode_frame,
2967     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED |
2968                       AV_CODEC_CAP_HWACCEL_VDPAU | AV_CODEC_CAP_DELAY,
2969     .flush          = flush,
2970 };
2971 #endif
2972
2973 #if CONFIG_MPEG1_VDPAU_DECODER && FF_API_VDPAU
2974 AVCodec ff_mpeg1_vdpau_decoder = {
2975     .name           = "mpeg1video_vdpau",
2976     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2977     .type           = AVMEDIA_TYPE_VIDEO,
2978     .id             = AV_CODEC_ID_MPEG1VIDEO,
2979     .priv_data_size = sizeof(Mpeg1Context),
2980     .init           = mpeg_decode_init,
2981     .close          = mpeg_decode_end,
2982     .decode         = mpeg_decode_frame,
2983     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED |
2984                       AV_CODEC_CAP_HWACCEL_VDPAU | AV_CODEC_CAP_DELAY,
2985     .flush          = flush,
2986 };
2987 #endif