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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     s->mpeg_enc_ctx_allocated      = 0;
1134     s->mpeg_enc_ctx.picture_number = 0;
1135     s->repeat_field                = 0;
1136     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1137     avctx->color_range             = AVCOL_RANGE_MPEG;
1138     return 0;
1139 }
1140
1141 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1142                                              const AVCodecContext *avctx_from)
1143 {
1144     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1145     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1146     int err;
1147
1148     if (avctx == avctx_from               ||
1149         !ctx_from->mpeg_enc_ctx_allocated ||
1150         !s1->context_initialized)
1151         return 0;
1152
1153     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1154     if (err)
1155         return err;
1156
1157     if (!ctx->mpeg_enc_ctx_allocated)
1158         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1159
1160     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1161         s->picture_number++;
1162
1163     return 0;
1164 }
1165
1166 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1167                                  const uint8_t *new_perm)
1168 {
1169     uint16_t temp_matrix[64];
1170     int i;
1171
1172     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1173
1174     for (i = 0; i < 64; i++)
1175         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1176 }
1177
1178 static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1179 #if CONFIG_MPEG1_XVMC_HWACCEL
1180     AV_PIX_FMT_XVMC,
1181 #endif
1182 #if CONFIG_MPEG1_VDPAU_DECODER && FF_API_VDPAU
1183     AV_PIX_FMT_VDPAU_MPEG1,
1184 #endif
1185 #if CONFIG_MPEG1_VDPAU_HWACCEL
1186     AV_PIX_FMT_VDPAU,
1187 #endif
1188     AV_PIX_FMT_YUV420P,
1189     AV_PIX_FMT_NONE
1190 };
1191
1192 static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1193 #if CONFIG_MPEG2_XVMC_HWACCEL
1194     AV_PIX_FMT_XVMC,
1195 #endif
1196 #if CONFIG_MPEG_VDPAU_DECODER && FF_API_VDPAU
1197     AV_PIX_FMT_VDPAU_MPEG2,
1198 #endif
1199 #if CONFIG_MPEG2_VDPAU_HWACCEL
1200     AV_PIX_FMT_VDPAU,
1201 #endif
1202 #if CONFIG_MPEG2_DXVA2_HWACCEL
1203     AV_PIX_FMT_DXVA2_VLD,
1204 #endif
1205 #if CONFIG_MPEG2_D3D11VA_HWACCEL
1206     AV_PIX_FMT_D3D11VA_VLD,
1207 #endif
1208 #if CONFIG_MPEG2_VAAPI_HWACCEL
1209     AV_PIX_FMT_VAAPI,
1210 #endif
1211 #if CONFIG_MPEG2_VIDEOTOOLBOX_HWACCEL
1212     AV_PIX_FMT_VIDEOTOOLBOX,
1213 #endif
1214     AV_PIX_FMT_YUV420P,
1215     AV_PIX_FMT_NONE
1216 };
1217
1218 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1219     AV_PIX_FMT_YUV422P,
1220     AV_PIX_FMT_NONE
1221 };
1222
1223 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1224     AV_PIX_FMT_YUV444P,
1225     AV_PIX_FMT_NONE
1226 };
1227
1228 #if FF_API_VDPAU
1229 static inline int uses_vdpau(AVCodecContext *avctx) {
1230     return avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG1 || avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG2;
1231 }
1232 #endif
1233
1234 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1235 {
1236     Mpeg1Context *s1  = avctx->priv_data;
1237     MpegEncContext *s = &s1->mpeg_enc_ctx;
1238     const enum AVPixelFormat *pix_fmts;
1239
1240     if (CONFIG_GRAY && (avctx->flags & AV_CODEC_FLAG_GRAY))
1241         return AV_PIX_FMT_GRAY8;
1242
1243     if (s->chroma_format < 2)
1244         pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1245                                 mpeg1_hwaccel_pixfmt_list_420 :
1246                                 mpeg2_hwaccel_pixfmt_list_420;
1247     else if (s->chroma_format == 2)
1248         pix_fmts = mpeg12_pixfmt_list_422;
1249     else
1250         pix_fmts = mpeg12_pixfmt_list_444;
1251
1252     return ff_thread_get_format(avctx, pix_fmts);
1253 }
1254
1255 static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
1256 {
1257     // until then pix_fmt may be changed right after codec init
1258     if (avctx->hwaccel
1259 #if FF_API_VDPAU
1260         || uses_vdpau(avctx)
1261 #endif
1262         )
1263         if (avctx->idct_algo == FF_IDCT_AUTO)
1264             avctx->idct_algo = FF_IDCT_SIMPLE;
1265
1266     if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
1267         Mpeg1Context *s1 = avctx->priv_data;
1268         MpegEncContext *s = &s1->mpeg_enc_ctx;
1269
1270         s->pack_pblocks = 1;
1271 #if FF_API_XVMC
1272 FF_DISABLE_DEPRECATION_WARNINGS
1273         avctx->xvmc_acceleration = 2;
1274 FF_ENABLE_DEPRECATION_WARNINGS
1275 #endif /* FF_API_XVMC */
1276     }
1277 }
1278
1279 /* Call this function when we know all parameters.
1280  * It may be called in different places for MPEG-1 and MPEG-2. */
1281 static int mpeg_decode_postinit(AVCodecContext *avctx)
1282 {
1283     Mpeg1Context *s1  = avctx->priv_data;
1284     MpegEncContext *s = &s1->mpeg_enc_ctx;
1285     uint8_t old_permutation[64];
1286     int ret;
1287
1288     if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1289         // MPEG-1 aspect
1290         avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1291     } else { // MPEG-2
1292         // MPEG-2 aspect
1293         if (s->aspect_ratio_info > 1) {
1294             AVRational dar =
1295                 av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1296                                   (AVRational) { s1->pan_scan.width,
1297                                                  s1->pan_scan.height }),
1298                          (AVRational) { s->width, s->height });
1299
1300             /* We ignore the spec here and guess a bit as reality does not
1301              * match the spec, see for example res_change_ffmpeg_aspect.ts
1302              * and sequence-display-aspect.mpg.
1303              * issue1613, 621, 562 */
1304             if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1305                 (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1306                  av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1307                 s->avctx->sample_aspect_ratio =
1308                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1309                              (AVRational) { s->width, s->height });
1310             } else {
1311                 s->avctx->sample_aspect_ratio =
1312                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1313                              (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1314 // issue1613 4/3 16/9 -> 16/9
1315 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1316 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1317 //                s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1318                 ff_dlog(avctx, "aspect A %d/%d\n",
1319                         ff_mpeg2_aspect[s->aspect_ratio_info].num,
1320                         ff_mpeg2_aspect[s->aspect_ratio_info].den);
1321                 ff_dlog(avctx, "aspect B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1322                         s->avctx->sample_aspect_ratio.den);
1323             }
1324         } else {
1325             s->avctx->sample_aspect_ratio =
1326                 ff_mpeg2_aspect[s->aspect_ratio_info];
1327         }
1328     } // MPEG-2
1329
1330     if (av_image_check_sar(s->width, s->height,
1331                            avctx->sample_aspect_ratio) < 0) {
1332         av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
1333                 avctx->sample_aspect_ratio.num,
1334                 avctx->sample_aspect_ratio.den);
1335         avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
1336     }
1337
1338     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1339         avctx->coded_width       != s->width                ||
1340         avctx->coded_height      != s->height               ||
1341         s1->save_width           != s->width                ||
1342         s1->save_height          != s->height               ||
1343         av_cmp_q(s1->save_aspect, s->avctx->sample_aspect_ratio) ||
1344         (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1345         0) {
1346         if (s1->mpeg_enc_ctx_allocated) {
1347             ParseContext pc = s->parse_context;
1348             s->parse_context.buffer = 0;
1349             ff_mpv_common_end(s);
1350             s->parse_context = pc;
1351             s1->mpeg_enc_ctx_allocated = 0;
1352         }
1353
1354         ret = ff_set_dimensions(avctx, s->width, s->height);
1355         if (ret < 0)
1356             return ret;
1357
1358         if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
1359             avctx->rc_max_rate = s->bit_rate;
1360         } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
1361                    (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
1362             avctx->bit_rate = s->bit_rate;
1363         }
1364         s1->save_aspect          = s->avctx->sample_aspect_ratio;
1365         s1->save_width           = s->width;
1366         s1->save_height          = s->height;
1367         s1->save_progressive_seq = s->progressive_sequence;
1368
1369         /* low_delay may be forced, in this case we will have B-frames
1370          * that behave like P-frames. */
1371         avctx->has_b_frames = !s->low_delay;
1372
1373         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1374             // MPEG-1 fps
1375             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1376             avctx->ticks_per_frame     = 1;
1377
1378             avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1379         } else { // MPEG-2
1380             // MPEG-2 fps
1381             av_reduce(&s->avctx->framerate.num,
1382                       &s->avctx->framerate.den,
1383                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1384                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1385                       1 << 30);
1386             avctx->ticks_per_frame = 2;
1387
1388             switch (s->chroma_format) {
1389             case 1: avctx->chroma_sample_location = AVCHROMA_LOC_LEFT; break;
1390             case 2:
1391             case 3: avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT; break;
1392             default: av_assert0(0);
1393             }
1394         } // MPEG-2
1395
1396         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1397         setup_hwaccel_for_pixfmt(avctx);
1398
1399         /* Quantization matrices may need reordering
1400          * if DCT permutation is changed. */
1401         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1402
1403         ff_mpv_idct_init(s);
1404         if ((ret = ff_mpv_common_init(s)) < 0)
1405             return ret;
1406
1407         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1408         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1409         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1410         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1411
1412         s1->mpeg_enc_ctx_allocated = 1;
1413     }
1414     return 0;
1415 }
1416
1417 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1418                                 int buf_size)
1419 {
1420     Mpeg1Context *s1  = avctx->priv_data;
1421     MpegEncContext *s = &s1->mpeg_enc_ctx;
1422     int ref, f_code, vbv_delay;
1423
1424     init_get_bits(&s->gb, buf, buf_size * 8);
1425
1426     ref = get_bits(&s->gb, 10); /* temporal ref */
1427     s->pict_type = get_bits(&s->gb, 3);
1428     if (s->pict_type == 0 || s->pict_type > 3)
1429         return AVERROR_INVALIDDATA;
1430
1431     vbv_delay = get_bits(&s->gb, 16);
1432     s->vbv_delay = vbv_delay;
1433     if (s->pict_type == AV_PICTURE_TYPE_P ||
1434         s->pict_type == AV_PICTURE_TYPE_B) {
1435         s->full_pel[0] = get_bits1(&s->gb);
1436         f_code = get_bits(&s->gb, 3);
1437         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1438             return AVERROR_INVALIDDATA;
1439         f_code += !f_code;
1440         s->mpeg_f_code[0][0] = f_code;
1441         s->mpeg_f_code[0][1] = f_code;
1442     }
1443     if (s->pict_type == AV_PICTURE_TYPE_B) {
1444         s->full_pel[1] = get_bits1(&s->gb);
1445         f_code = get_bits(&s->gb, 3);
1446         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1447             return AVERROR_INVALIDDATA;
1448         f_code += !f_code;
1449         s->mpeg_f_code[1][0] = f_code;
1450         s->mpeg_f_code[1][1] = f_code;
1451     }
1452     s->current_picture.f->pict_type = s->pict_type;
1453     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1454
1455     if (avctx->debug & FF_DEBUG_PICT_INFO)
1456         av_log(avctx, AV_LOG_DEBUG,
1457                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1458
1459     s->y_dc_scale = 8;
1460     s->c_dc_scale = 8;
1461     return 0;
1462 }
1463
1464 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1465 {
1466     MpegEncContext *s = &s1->mpeg_enc_ctx;
1467     int horiz_size_ext, vert_size_ext;
1468     int bit_rate_ext;
1469
1470     skip_bits(&s->gb, 1); /* profile and level esc*/
1471     s->avctx->profile       = get_bits(&s->gb, 3);
1472     s->avctx->level         = get_bits(&s->gb, 4);
1473     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1474     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1475
1476     if (!s->chroma_format) {
1477         s->chroma_format = 1;
1478         av_log(s->avctx, AV_LOG_WARNING, "Chroma format invalid\n");
1479     }
1480
1481     horiz_size_ext          = get_bits(&s->gb, 2);
1482     vert_size_ext           = get_bits(&s->gb, 2);
1483     s->width  |= (horiz_size_ext << 12);
1484     s->height |= (vert_size_ext  << 12);
1485     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1486     s->bit_rate += (bit_rate_ext << 18) * 400LL;
1487     check_marker(&s->gb, "after bit rate extension");
1488     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1489
1490     s->low_delay = get_bits1(&s->gb);
1491     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
1492         s->low_delay = 1;
1493
1494     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1495     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1496
1497     ff_dlog(s->avctx, "sequence extension\n");
1498     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1499
1500     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1501         av_log(s->avctx, AV_LOG_DEBUG,
1502                "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%"PRId64"\n",
1503                s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1504                s->avctx->rc_buffer_size, s->bit_rate);
1505 }
1506
1507 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1508 {
1509     MpegEncContext *s = &s1->mpeg_enc_ctx;
1510     int color_description, w, h;
1511
1512     skip_bits(&s->gb, 3); /* video format */
1513     color_description = get_bits1(&s->gb);
1514     if (color_description) {
1515         s->avctx->color_primaries = get_bits(&s->gb, 8);
1516         s->avctx->color_trc       = get_bits(&s->gb, 8);
1517         s->avctx->colorspace      = get_bits(&s->gb, 8);
1518     }
1519     w = get_bits(&s->gb, 14);
1520     skip_bits(&s->gb, 1); // marker
1521     h = get_bits(&s->gb, 14);
1522     // remaining 3 bits are zero padding
1523
1524     s1->pan_scan.width  = 16 * w;
1525     s1->pan_scan.height = 16 * h;
1526
1527     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1528         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1529 }
1530
1531 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1532 {
1533     MpegEncContext *s = &s1->mpeg_enc_ctx;
1534     int i, nofco;
1535
1536     nofco = 1;
1537     if (s->progressive_sequence) {
1538         if (s->repeat_first_field) {
1539             nofco++;
1540             if (s->top_field_first)
1541                 nofco++;
1542         }
1543     } else {
1544         if (s->picture_structure == PICT_FRAME) {
1545             nofco++;
1546             if (s->repeat_first_field)
1547                 nofco++;
1548         }
1549     }
1550     for (i = 0; i < nofco; i++) {
1551         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1552         skip_bits(&s->gb, 1); // marker
1553         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1554         skip_bits(&s->gb, 1); // marker
1555     }
1556
1557     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1558         av_log(s->avctx, AV_LOG_DEBUG,
1559                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1560                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1561                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1562                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1563 }
1564
1565 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1566                        uint16_t matrix1[64], int intra)
1567 {
1568     int i;
1569
1570     for (i = 0; i < 64; i++) {
1571         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1572         int v = get_bits(&s->gb, 8);
1573         if (v == 0) {
1574             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1575             return AVERROR_INVALIDDATA;
1576         }
1577         if (intra && i == 0 && v != 8) {
1578             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1579             v = 8; // needed by pink.mpg / issue1046
1580         }
1581         matrix0[j] = v;
1582         if (matrix1)
1583             matrix1[j] = v;
1584     }
1585     return 0;
1586 }
1587
1588 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1589 {
1590     ff_dlog(s->avctx, "matrix extension\n");
1591
1592     if (get_bits1(&s->gb))
1593         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1594     if (get_bits1(&s->gb))
1595         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1596     if (get_bits1(&s->gb))
1597         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1598     if (get_bits1(&s->gb))
1599         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1600 }
1601
1602 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1603 {
1604     MpegEncContext *s = &s1->mpeg_enc_ctx;
1605
1606     s->full_pel[0]       = s->full_pel[1] = 0;
1607     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1608     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1609     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1610     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1611     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1612         av_log(s->avctx, AV_LOG_ERROR,
1613                "Missing picture start code, guessing missing values\n");
1614         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1615             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1616                 s->pict_type = AV_PICTURE_TYPE_I;
1617             else
1618                 s->pict_type = AV_PICTURE_TYPE_P;
1619         } else
1620             s->pict_type = AV_PICTURE_TYPE_B;
1621         s->current_picture.f->pict_type = s->pict_type;
1622         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1623     }
1624     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1625     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1626     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1627     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1628
1629     s->intra_dc_precision         = get_bits(&s->gb, 2);
1630     s->picture_structure          = get_bits(&s->gb, 2);
1631     s->top_field_first            = get_bits1(&s->gb);
1632     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1633     s->concealment_motion_vectors = get_bits1(&s->gb);
1634     s->q_scale_type               = get_bits1(&s->gb);
1635     s->intra_vlc_format           = get_bits1(&s->gb);
1636     s->alternate_scan             = get_bits1(&s->gb);
1637     s->repeat_first_field         = get_bits1(&s->gb);
1638     s->chroma_420_type            = get_bits1(&s->gb);
1639     s->progressive_frame          = get_bits1(&s->gb);
1640
1641     if (s->alternate_scan) {
1642         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1643         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1644     } else {
1645         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1646         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1647     }
1648
1649     /* composite display not parsed */
1650     ff_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1651     ff_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1652     ff_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1653     ff_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1654     ff_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1655     ff_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1656     ff_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1657     ff_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1658     ff_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1659 }
1660
1661 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1662 {
1663     AVCodecContext *avctx = s->avctx;
1664     Mpeg1Context *s1      = (Mpeg1Context *) s;
1665     int ret;
1666
1667     /* start frame decoding */
1668     if (s->first_field || s->picture_structure == PICT_FRAME) {
1669         AVFrameSideData *pan_scan;
1670
1671         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1672             return ret;
1673
1674         ff_mpeg_er_frame_start(s);
1675
1676         /* first check if we must repeat the frame */
1677         s->current_picture_ptr->f->repeat_pict = 0;
1678         if (s->repeat_first_field) {
1679             if (s->progressive_sequence) {
1680                 if (s->top_field_first)
1681                     s->current_picture_ptr->f->repeat_pict = 4;
1682                 else
1683                     s->current_picture_ptr->f->repeat_pict = 2;
1684             } else if (s->progressive_frame) {
1685                 s->current_picture_ptr->f->repeat_pict = 1;
1686             }
1687         }
1688
1689         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1690                                           AV_FRAME_DATA_PANSCAN,
1691                                           sizeof(s1->pan_scan));
1692         if (!pan_scan)
1693             return AVERROR(ENOMEM);
1694         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1695
1696         if (s1->a53_caption) {
1697             AVFrameSideData *sd = av_frame_new_side_data(
1698                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1699                 s1->a53_caption_size);
1700             if (sd)
1701                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1702             av_freep(&s1->a53_caption);
1703             avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
1704         }
1705
1706         if (s1->has_stereo3d) {
1707             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1708             if (!stereo)
1709                 return AVERROR(ENOMEM);
1710
1711             *stereo = s1->stereo3d;
1712             s1->has_stereo3d = 0;
1713         }
1714
1715         if (s1->has_afd) {
1716             AVFrameSideData *sd =
1717                 av_frame_new_side_data(s->current_picture_ptr->f,
1718                                        AV_FRAME_DATA_AFD, 1);
1719             if (!sd)
1720                 return AVERROR(ENOMEM);
1721
1722             *sd->data   = s1->afd;
1723             s1->has_afd = 0;
1724         }
1725
1726         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1727             ff_thread_finish_setup(avctx);
1728     } else { // second field
1729         int i;
1730
1731         if (!s->current_picture_ptr) {
1732             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1733             return AVERROR_INVALIDDATA;
1734         }
1735
1736         if (s->avctx->hwaccel &&
1737             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1738             if ((ret = s->avctx->hwaccel->end_frame(s->avctx)) < 0) {
1739                 av_log(avctx, AV_LOG_ERROR,
1740                        "hardware accelerator failed to decode first field\n");
1741                 return ret;
1742             }
1743         }
1744
1745         for (i = 0; i < 4; i++) {
1746             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1747             if (s->picture_structure == PICT_BOTTOM_FIELD)
1748                 s->current_picture.f->data[i] +=
1749                     s->current_picture_ptr->f->linesize[i];
1750         }
1751     }
1752
1753     if (avctx->hwaccel) {
1754         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1755             return ret;
1756     }
1757
1758     return 0;
1759 }
1760
1761 #define DECODE_SLICE_ERROR -1
1762 #define DECODE_SLICE_OK     0
1763
1764 /**
1765  * Decode a slice.
1766  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1767  * @return DECODE_SLICE_ERROR if the slice is damaged,
1768  *         DECODE_SLICE_OK if this slice is OK
1769  */
1770 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1771                              const uint8_t **buf, int buf_size)
1772 {
1773     AVCodecContext *avctx = s->avctx;
1774     const int lowres      = s->avctx->lowres;
1775     const int field_pic   = s->picture_structure != PICT_FRAME;
1776     int ret;
1777
1778     s->resync_mb_x =
1779     s->resync_mb_y = -1;
1780
1781     av_assert0(mb_y < s->mb_height);
1782
1783     init_get_bits(&s->gb, *buf, buf_size * 8);
1784     if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1785         skip_bits(&s->gb, 3);
1786
1787     ff_mpeg1_clean_buffers(s);
1788     s->interlaced_dct = 0;
1789
1790     s->qscale = get_qscale(s);
1791
1792     if (s->qscale == 0) {
1793         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1794         return AVERROR_INVALIDDATA;
1795     }
1796
1797     /* extra slice info */
1798     if (skip_1stop_8data_bits(&s->gb) < 0)
1799         return AVERROR_INVALIDDATA;
1800
1801     s->mb_x = 0;
1802
1803     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1804         skip_bits1(&s->gb);
1805     } else {
1806         while (get_bits_left(&s->gb) > 0) {
1807             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1808                                 MBINCR_VLC_BITS, 2);
1809             if (code < 0) {
1810                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1811                 return AVERROR_INVALIDDATA;
1812             }
1813             if (code >= 33) {
1814                 if (code == 33)
1815                     s->mb_x += 33;
1816                 /* otherwise, stuffing, nothing to do */
1817             } else {
1818                 s->mb_x += code;
1819                 break;
1820             }
1821         }
1822     }
1823
1824     if (s->mb_x >= (unsigned) s->mb_width) {
1825         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1826         return AVERROR_INVALIDDATA;
1827     }
1828
1829     if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1830         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1831         int start_code = -1;
1832         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1833         if (buf_end < *buf + buf_size)
1834             buf_end -= 4;
1835         s->mb_y = mb_y;
1836         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1837             return DECODE_SLICE_ERROR;
1838         *buf = buf_end;
1839         return DECODE_SLICE_OK;
1840     }
1841
1842     s->resync_mb_x = s->mb_x;
1843     s->resync_mb_y = s->mb_y = mb_y;
1844     s->mb_skip_run = 0;
1845     ff_init_block_index(s);
1846
1847     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1848         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1849             av_log(s->avctx, AV_LOG_DEBUG,
1850                    "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",
1851                    s->qscale,
1852                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1853                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1854                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1855                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1856                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1857                    s->progressive_sequence ? "ps"  : "",
1858                    s->progressive_frame    ? "pf"  : "",
1859                    s->alternate_scan       ? "alt" : "",
1860                    s->top_field_first      ? "top" : "",
1861                    s->intra_dc_precision, s->picture_structure,
1862                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1863                    s->q_scale_type, s->intra_vlc_format,
1864                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1865         }
1866     }
1867
1868     for (;;) {
1869         // If 1, we memcpy blocks in xvmcvideo.
1870         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1871             ff_xvmc_init_block(s); // set s->block
1872
1873         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1874             return ret;
1875
1876         // Note motion_val is normally NULL unless we want to extract the MVs.
1877         if (s->current_picture.motion_val[0] && !s->encoding) {
1878             const int wrap = s->b8_stride;
1879             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1880             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1881             int motion_x, motion_y, dir, i;
1882
1883             for (i = 0; i < 2; i++) {
1884                 for (dir = 0; dir < 2; dir++) {
1885                     if (s->mb_intra ||
1886                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1887                         motion_x = motion_y = 0;
1888                     } else if (s->mv_type == MV_TYPE_16X16 ||
1889                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1890                         motion_x = s->mv[dir][0][0];
1891                         motion_y = s->mv[dir][0][1];
1892                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1893                         motion_x = s->mv[dir][i][0];
1894                         motion_y = s->mv[dir][i][1];
1895                     }
1896
1897                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1898                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1899                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1900                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1901                     s->current_picture.ref_index [dir][b8_xy]     =
1902                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1903                     av_assert2(s->field_select[dir][i] == 0 ||
1904                                s->field_select[dir][i] == 1);
1905                 }
1906                 xy    += wrap;
1907                 b8_xy += 2;
1908             }
1909         }
1910
1911         s->dest[0] += 16 >> lowres;
1912         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1913         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1914
1915         ff_mpv_decode_mb(s, s->block);
1916
1917         if (++s->mb_x >= s->mb_width) {
1918             const int mb_size = 16 >> s->avctx->lowres;
1919
1920             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1921             ff_mpv_report_decode_progress(s);
1922
1923             s->mb_x  = 0;
1924             s->mb_y += 1 << field_pic;
1925
1926             if (s->mb_y >= s->mb_height) {
1927                 int left   = get_bits_left(&s->gb);
1928                 int is_d10 = s->chroma_format == 2 &&
1929                              s->pict_type == AV_PICTURE_TYPE_I &&
1930                              avctx->profile == 0 && avctx->level == 5 &&
1931                              s->intra_dc_precision == 2 &&
1932                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1933                              s->progressive_frame == 0
1934                              /* vbv_delay == 0xBBB || 0xE10 */;
1935
1936                 if (left >= 32 && !is_d10) {
1937                     GetBitContext gb = s->gb;
1938                     align_get_bits(&gb);
1939                     if (show_bits(&gb, 24) == 0x060E2B) {
1940                         av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
1941                         is_d10 = 1;
1942                     }
1943                 }
1944
1945                 if (left < 0 ||
1946                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1947                     ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1948                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1949                            left, show_bits(&s->gb, FFMIN(left, 23)));
1950                     return AVERROR_INVALIDDATA;
1951                 } else
1952                     goto eos;
1953             }
1954             // There are some files out there which are missing the last slice
1955             // in cases where the slice is completely outside the visible
1956             // area, we detect this here instead of running into the end expecting
1957             // more data
1958             if (s->mb_y >= ((s->height + 15) >> 4) &&
1959                 !s->progressive_sequence &&
1960                 get_bits_left(&s->gb) <= 8 &&
1961                 get_bits_left(&s->gb) >= 0 &&
1962                 s->mb_skip_run == -1 &&
1963                 show_bits(&s->gb, 8) == 0)
1964                 goto eos;
1965
1966             ff_init_block_index(s);
1967         }
1968
1969         /* skip mb handling */
1970         if (s->mb_skip_run == -1) {
1971             /* read increment again */
1972             s->mb_skip_run = 0;
1973             for (;;) {
1974                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1975                                     MBINCR_VLC_BITS, 2);
1976                 if (code < 0) {
1977                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1978                     return AVERROR_INVALIDDATA;
1979                 }
1980                 if (code >= 33) {
1981                     if (code == 33) {
1982                         s->mb_skip_run += 33;
1983                     } else if (code == 35) {
1984                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1985                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1986                             return AVERROR_INVALIDDATA;
1987                         }
1988                         goto eos; /* end of slice */
1989                     }
1990                     /* otherwise, stuffing, nothing to do */
1991                 } else {
1992                     s->mb_skip_run += code;
1993                     break;
1994                 }
1995             }
1996             if (s->mb_skip_run) {
1997                 int i;
1998                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1999                     av_log(s->avctx, AV_LOG_ERROR,
2000                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
2001                     return AVERROR_INVALIDDATA;
2002                 }
2003
2004                 /* skip mb */
2005                 s->mb_intra = 0;
2006                 for (i = 0; i < 12; i++)
2007                     s->block_last_index[i] = -1;
2008                 if (s->picture_structure == PICT_FRAME)
2009                     s->mv_type = MV_TYPE_16X16;
2010                 else
2011                     s->mv_type = MV_TYPE_FIELD;
2012                 if (s->pict_type == AV_PICTURE_TYPE_P) {
2013                     /* if P type, zero motion vector is implied */
2014                     s->mv_dir             = MV_DIR_FORWARD;
2015                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
2016                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
2017                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
2018                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
2019                 } else {
2020                     /* if B type, reuse previous vectors and directions */
2021                     s->mv[0][0][0] = s->last_mv[0][0][0];
2022                     s->mv[0][0][1] = s->last_mv[0][0][1];
2023                     s->mv[1][0][0] = s->last_mv[1][0][0];
2024                     s->mv[1][0][1] = s->last_mv[1][0][1];
2025                 }
2026             }
2027         }
2028     }
2029 eos: // end of slice
2030     if (get_bits_left(&s->gb) < 0) {
2031         av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
2032         return AVERROR_INVALIDDATA;
2033     }
2034     *buf += (get_bits_count(&s->gb) - 1) / 8;
2035     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);
2036     return 0;
2037 }
2038
2039 static int slice_decode_thread(AVCodecContext *c, void *arg)
2040 {
2041     MpegEncContext *s   = *(void **) arg;
2042     const uint8_t *buf  = s->gb.buffer;
2043     int mb_y            = s->start_mb_y;
2044     const int field_pic = s->picture_structure != PICT_FRAME;
2045
2046     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
2047
2048     for (;;) {
2049         uint32_t start_code;
2050         int ret;
2051
2052         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
2053         emms_c();
2054         ff_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2055                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
2056                 s->start_mb_y, s->end_mb_y, s->er.error_count);
2057         if (ret < 0) {
2058             if (c->err_recognition & AV_EF_EXPLODE)
2059                 return ret;
2060             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
2061                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2062                                 s->mb_x, s->mb_y,
2063                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2064         } else {
2065             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2066                             s->mb_x - 1, s->mb_y,
2067                             ER_AC_END | ER_DC_END | ER_MV_END);
2068         }
2069
2070         if (s->mb_y == s->end_mb_y)
2071             return 0;
2072
2073         start_code = -1;
2074         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2075         mb_y       = start_code - SLICE_MIN_START_CODE;
2076         if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2077             mb_y += (*buf&0xE0)<<2;
2078         mb_y <<= field_pic;
2079         if (s->picture_structure == PICT_BOTTOM_FIELD)
2080             mb_y++;
2081         if (mb_y < 0 || mb_y >= s->end_mb_y)
2082             return AVERROR_INVALIDDATA;
2083     }
2084 }
2085
2086 /**
2087  * Handle slice ends.
2088  * @return 1 if it seems to be the last slice
2089  */
2090 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2091 {
2092     Mpeg1Context *s1  = avctx->priv_data;
2093     MpegEncContext *s = &s1->mpeg_enc_ctx;
2094
2095     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2096         return 0;
2097
2098     if (s->avctx->hwaccel) {
2099         int ret = s->avctx->hwaccel->end_frame(s->avctx);
2100         if (ret < 0) {
2101             av_log(avctx, AV_LOG_ERROR,
2102                    "hardware accelerator failed to decode picture\n");
2103             return ret;
2104         }
2105     }
2106
2107     /* end of slice reached */
2108     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
2109         /* end of image */
2110
2111         ff_er_frame_end(&s->er);
2112
2113         ff_mpv_frame_end(s);
2114
2115         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2116             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2117             if (ret < 0)
2118                 return ret;
2119             ff_print_debug_info(s, s->current_picture_ptr, pict);
2120             ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2121         } else {
2122             if (avctx->active_thread_type & FF_THREAD_FRAME)
2123                 s->picture_number++;
2124             /* latency of 1 frame for I- and P-frames */
2125             /* XXX: use another variable than picture_number */
2126             if (s->last_picture_ptr) {
2127                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2128                 if (ret < 0)
2129                     return ret;
2130                 ff_print_debug_info(s, s->last_picture_ptr, pict);
2131                 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2132             }
2133         }
2134
2135         return 1;
2136     } else {
2137         return 0;
2138     }
2139 }
2140
2141 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2142                                  const uint8_t *buf, int buf_size)
2143 {
2144     Mpeg1Context *s1  = avctx->priv_data;
2145     MpegEncContext *s = &s1->mpeg_enc_ctx;
2146     int width, height;
2147     int i, v, j;
2148
2149     init_get_bits(&s->gb, buf, buf_size * 8);
2150
2151     width  = get_bits(&s->gb, 12);
2152     height = get_bits(&s->gb, 12);
2153     if (width == 0 || height == 0) {
2154         av_log(avctx, AV_LOG_WARNING,
2155                "Invalid horizontal or vertical size value.\n");
2156         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2157             return AVERROR_INVALIDDATA;
2158     }
2159     s->aspect_ratio_info = get_bits(&s->gb, 4);
2160     if (s->aspect_ratio_info == 0) {
2161         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2162         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2163             return AVERROR_INVALIDDATA;
2164     }
2165     s->frame_rate_index = get_bits(&s->gb, 4);
2166     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2167         av_log(avctx, AV_LOG_WARNING,
2168                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2169         s->frame_rate_index = 1;
2170     }
2171     s->bit_rate = get_bits(&s->gb, 18) * 400LL;
2172     if (check_marker(&s->gb, "in sequence header") == 0) {
2173         return AVERROR_INVALIDDATA;
2174     }
2175
2176     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2177     skip_bits(&s->gb, 1);
2178
2179     /* get matrix */
2180     if (get_bits1(&s->gb)) {
2181         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2182     } else {
2183         for (i = 0; i < 64; i++) {
2184             j = s->idsp.idct_permutation[i];
2185             v = ff_mpeg1_default_intra_matrix[i];
2186             s->intra_matrix[j]        = v;
2187             s->chroma_intra_matrix[j] = v;
2188         }
2189     }
2190     if (get_bits1(&s->gb)) {
2191         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2192     } else {
2193         for (i = 0; i < 64; i++) {
2194             int j = s->idsp.idct_permutation[i];
2195             v = ff_mpeg1_default_non_intra_matrix[i];
2196             s->inter_matrix[j]        = v;
2197             s->chroma_inter_matrix[j] = v;
2198         }
2199     }
2200
2201     if (show_bits(&s->gb, 23) != 0) {
2202         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2203         return AVERROR_INVALIDDATA;
2204     }
2205
2206     s->width  = width;
2207     s->height = height;
2208
2209     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2210     s->progressive_sequence = 1;
2211     s->progressive_frame    = 1;
2212     s->picture_structure    = PICT_FRAME;
2213     s->first_field          = 0;
2214     s->frame_pred_frame_dct = 1;
2215     s->chroma_format        = 1;
2216     s->codec_id             =
2217     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2218     s->out_format           = FMT_MPEG1;
2219     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2220     if (s->avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
2221         s->low_delay = 1;
2222
2223     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2224         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%"PRId64", aspect_ratio_info: %d \n",
2225                s->avctx->rc_buffer_size, s->bit_rate, s->aspect_ratio_info);
2226
2227     return 0;
2228 }
2229
2230 static int vcr2_init_sequence(AVCodecContext *avctx)
2231 {
2232     Mpeg1Context *s1  = avctx->priv_data;
2233     MpegEncContext *s = &s1->mpeg_enc_ctx;
2234     int i, v, ret;
2235
2236     /* start new MPEG-1 context decoding */
2237     s->out_format = FMT_MPEG1;
2238     if (s1->mpeg_enc_ctx_allocated) {
2239         ff_mpv_common_end(s);
2240         s1->mpeg_enc_ctx_allocated = 0;
2241     }
2242     s->width            = avctx->coded_width;
2243     s->height           = avctx->coded_height;
2244     avctx->has_b_frames = 0; // true?
2245     s->low_delay        = 1;
2246
2247     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2248     setup_hwaccel_for_pixfmt(avctx);
2249
2250     ff_mpv_idct_init(s);
2251     if ((ret = ff_mpv_common_init(s)) < 0)
2252         return ret;
2253     s1->mpeg_enc_ctx_allocated = 1;
2254
2255     for (i = 0; i < 64; i++) {
2256         int j = s->idsp.idct_permutation[i];
2257         v = ff_mpeg1_default_intra_matrix[i];
2258         s->intra_matrix[j]        = v;
2259         s->chroma_intra_matrix[j] = v;
2260
2261         v = ff_mpeg1_default_non_intra_matrix[i];
2262         s->inter_matrix[j]        = v;
2263         s->chroma_inter_matrix[j] = v;
2264     }
2265
2266     s->progressive_sequence  = 1;
2267     s->progressive_frame     = 1;
2268     s->picture_structure     = PICT_FRAME;
2269     s->first_field           = 0;
2270     s->frame_pred_frame_dct  = 1;
2271     s->chroma_format         = 1;
2272     if (s->codec_tag == AV_RL32("BW10")) {
2273         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2274     } else {
2275         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2276         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2277     }
2278     s1->save_width           = s->width;
2279     s1->save_height          = s->height;
2280     s1->save_progressive_seq = s->progressive_sequence;
2281     return 0;
2282 }
2283
2284 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2285                               const uint8_t *p, int buf_size)
2286 {
2287     Mpeg1Context *s1 = avctx->priv_data;
2288
2289     if (buf_size >= 6 &&
2290         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2291         p[4] == 3 && (p[5] & 0x40)) {
2292         /* extract A53 Part 4 CC data */
2293         int cc_count = p[5] & 0x1f;
2294         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2295             av_freep(&s1->a53_caption);
2296             s1->a53_caption_size = cc_count * 3;
2297             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2298             if (s1->a53_caption)
2299                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2300         }
2301         return 1;
2302     } else if (buf_size >= 11 &&
2303                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2304         /* extract DVD CC data */
2305         int cc_count = 0;
2306         int i;
2307         // There is a caption count field in the data, but it is often
2308         // incorect.  So count the number of captions present.
2309         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2310             cc_count++;
2311         // Transform the DVD format into A53 Part 4 format
2312         if (cc_count > 0) {
2313             av_freep(&s1->a53_caption);
2314             s1->a53_caption_size = cc_count * 6;
2315             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2316             if (s1->a53_caption) {
2317                 uint8_t field1 = !!(p[4] & 0x80);
2318                 uint8_t *cap = s1->a53_caption;
2319                 p += 5;
2320                 for (i = 0; i < cc_count; i++) {
2321                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2322                     cap[1] = p[1];
2323                     cap[2] = p[2];
2324                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2325                     cap[4] = p[4];
2326                     cap[5] = p[5];
2327                     cap += 6;
2328                     p += 6;
2329                 }
2330             }
2331         }
2332         return 1;
2333     }
2334     return 0;
2335 }
2336
2337 static void mpeg_decode_user_data(AVCodecContext *avctx,
2338                                   const uint8_t *p, int buf_size)
2339 {
2340     Mpeg1Context *s = avctx->priv_data;
2341     const uint8_t *buf_end = p + buf_size;
2342     Mpeg1Context *s1 = avctx->priv_data;
2343
2344 #if 0
2345     int i;
2346     for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2347         av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
2348     }
2349     av_log(avctx, AV_LOG_ERROR, "\n");
2350 #endif
2351
2352     if (buf_size > 29){
2353         int i;
2354         for(i=0; i<20; i++)
2355             if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2356                 s->tmpgexs= 1;
2357             }
2358     }
2359     /* we parse the DTG active format information */
2360     if (buf_end - p >= 5 &&
2361         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2362         int flags = p[4];
2363         p += 5;
2364         if (flags & 0x80) {
2365             /* skip event id */
2366             p += 2;
2367         }
2368         if (flags & 0x40) {
2369             if (buf_end - p < 1)
2370                 return;
2371 #if FF_API_AFD
2372 FF_DISABLE_DEPRECATION_WARNINGS
2373             avctx->dtg_active_format = p[0] & 0x0f;
2374 FF_ENABLE_DEPRECATION_WARNINGS
2375 #endif /* FF_API_AFD */
2376             s1->has_afd = 1;
2377             s1->afd     = p[0] & 0x0f;
2378         }
2379     } else if (buf_end - p >= 6 &&
2380                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2381                p[4] == 0x03) { // S3D_video_format_length
2382         // the 0x7F mask ignores the reserved_bit value
2383         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2384
2385         if (S3D_video_format_type == 0x03 ||
2386             S3D_video_format_type == 0x04 ||
2387             S3D_video_format_type == 0x08 ||
2388             S3D_video_format_type == 0x23) {
2389
2390             s1->has_stereo3d = 1;
2391
2392             switch (S3D_video_format_type) {
2393             case 0x03:
2394                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2395                 break;
2396             case 0x04:
2397                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2398                 break;
2399             case 0x08:
2400                 s1->stereo3d.type = AV_STEREO3D_2D;
2401                 break;
2402             case 0x23:
2403                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2404                 break;
2405             }
2406         }
2407     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2408         return;
2409     }
2410 }
2411
2412 static void mpeg_decode_gop(AVCodecContext *avctx,
2413                             const uint8_t *buf, int buf_size)
2414 {
2415     Mpeg1Context *s1  = avctx->priv_data;
2416     MpegEncContext *s = &s1->mpeg_enc_ctx;
2417     int broken_link;
2418     int64_t tc;
2419
2420     init_get_bits(&s->gb, buf, buf_size * 8);
2421
2422     tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2423
2424     s->closed_gop = get_bits1(&s->gb);
2425     /* broken_link indicate that after editing the
2426      * reference frames of the first B-Frames after GOP I-Frame
2427      * are missing (open gop) */
2428     broken_link = get_bits1(&s->gb);
2429
2430     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2431         char tcbuf[AV_TIMECODE_STR_SIZE];
2432         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2433         av_log(s->avctx, AV_LOG_DEBUG,
2434                "GOP (%s) closed_gop=%d broken_link=%d\n",
2435                tcbuf, s->closed_gop, broken_link);
2436     }
2437 }
2438
2439 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2440                          int *got_output, const uint8_t *buf, int buf_size)
2441 {
2442     Mpeg1Context *s = avctx->priv_data;
2443     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2444     const uint8_t *buf_ptr = buf;
2445     const uint8_t *buf_end = buf + buf_size;
2446     int ret, input_size;
2447     int last_code = 0, skip_frame = 0;
2448     int picture_start_code_seen = 0;
2449
2450     for (;;) {
2451         /* find next start code */
2452         uint32_t start_code = -1;
2453         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2454         if (start_code > 0x1ff) {
2455             if (!skip_frame) {
2456                 if (HAVE_THREADS &&
2457                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2458                     !avctx->hwaccel) {
2459                     int i;
2460                     av_assert0(avctx->thread_count > 1);
2461
2462                     avctx->execute(avctx, slice_decode_thread,
2463                                    &s2->thread_context[0], NULL,
2464                                    s->slice_count, sizeof(void *));
2465                     for (i = 0; i < s->slice_count; i++)
2466                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2467                 }
2468
2469 #if FF_API_VDPAU
2470                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2471                     && uses_vdpau(avctx))
2472                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2473 #endif
2474
2475                 ret = slice_end(avctx, picture);
2476                 if (ret < 0)
2477                     return ret;
2478                 else if (ret) {
2479                     // FIXME: merge with the stuff in mpeg_decode_slice
2480                     if (s2->last_picture_ptr || s2->low_delay)
2481                         *got_output = 1;
2482                 }
2483             }
2484             s2->pict_type = 0;
2485
2486             if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
2487                 return AVERROR_INVALIDDATA;
2488
2489             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2490         }
2491
2492         input_size = buf_end - buf_ptr;
2493
2494         if (avctx->debug & FF_DEBUG_STARTCODE)
2495             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2496                    start_code, buf_ptr - buf, input_size);
2497
2498         /* prepare data for next start code */
2499         switch (start_code) {
2500         case SEQ_START_CODE:
2501             if (last_code == 0) {
2502                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2503                 if (buf != avctx->extradata)
2504                     s->sync = 1;
2505             } else {
2506                 av_log(avctx, AV_LOG_ERROR,
2507                        "ignoring SEQ_START_CODE after %X\n", last_code);
2508                 if (avctx->err_recognition & AV_EF_EXPLODE)
2509                     return AVERROR_INVALIDDATA;
2510             }
2511             break;
2512
2513         case PICTURE_START_CODE:
2514             if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
2515                /* If it's a frame picture, there can't be more than one picture header.
2516                   Yet, it does happen and we need to handle it. */
2517                av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
2518                break;
2519             }
2520             picture_start_code_seen = 1;
2521
2522             if (s2->width <= 0 || s2->height <= 0) {
2523                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2524                        s2->width, s2->height);
2525                 return AVERROR_INVALIDDATA;
2526             }
2527
2528             if (s->tmpgexs){
2529                 s2->intra_dc_precision= 3;
2530                 s2->intra_matrix[0]= 1;
2531             }
2532             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2533                 !avctx->hwaccel && s->slice_count) {
2534                 int i;
2535
2536                 avctx->execute(avctx, slice_decode_thread,
2537                                s2->thread_context, NULL,
2538                                s->slice_count, sizeof(void *));
2539                 for (i = 0; i < s->slice_count; i++)
2540                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2541                 s->slice_count = 0;
2542             }
2543             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2544                 ret = mpeg_decode_postinit(avctx);
2545                 if (ret < 0) {
2546                     av_log(avctx, AV_LOG_ERROR,
2547                            "mpeg_decode_postinit() failure\n");
2548                     return ret;
2549                 }
2550
2551                 /* We have a complete image: we try to decompress it. */
2552                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2553                     s2->pict_type = 0;
2554                 s->first_slice = 1;
2555                 last_code      = PICTURE_START_CODE;
2556             } else {
2557                 av_log(avctx, AV_LOG_ERROR,
2558                        "ignoring pic after %X\n", last_code);
2559                 if (avctx->err_recognition & AV_EF_EXPLODE)
2560                     return AVERROR_INVALIDDATA;
2561             }
2562             break;
2563         case EXT_START_CODE:
2564             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2565
2566             switch (get_bits(&s2->gb, 4)) {
2567             case 0x1:
2568                 if (last_code == 0) {
2569                     mpeg_decode_sequence_extension(s);
2570                 } else {
2571                     av_log(avctx, AV_LOG_ERROR,
2572                            "ignoring seq ext after %X\n", last_code);
2573                     if (avctx->err_recognition & AV_EF_EXPLODE)
2574                         return AVERROR_INVALIDDATA;
2575                 }
2576                 break;
2577             case 0x2:
2578                 mpeg_decode_sequence_display_extension(s);
2579                 break;
2580             case 0x3:
2581                 mpeg_decode_quant_matrix_extension(s2);
2582                 break;
2583             case 0x7:
2584                 mpeg_decode_picture_display_extension(s);
2585                 break;
2586             case 0x8:
2587                 if (last_code == PICTURE_START_CODE) {
2588                     mpeg_decode_picture_coding_extension(s);
2589                 } else {
2590                     av_log(avctx, AV_LOG_ERROR,
2591                            "ignoring pic cod ext after %X\n", last_code);
2592                     if (avctx->err_recognition & AV_EF_EXPLODE)
2593                         return AVERROR_INVALIDDATA;
2594                 }
2595                 break;
2596             }
2597             break;
2598         case USER_START_CODE:
2599             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2600             break;
2601         case GOP_START_CODE:
2602             if (last_code == 0) {
2603                 s2->first_field = 0;
2604                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2605                 s->sync = 1;
2606             } else {
2607                 av_log(avctx, AV_LOG_ERROR,
2608                        "ignoring GOP_START_CODE after %X\n", last_code);
2609                 if (avctx->err_recognition & AV_EF_EXPLODE)
2610                     return AVERROR_INVALIDDATA;
2611             }
2612             break;
2613         default:
2614             if (start_code >= SLICE_MIN_START_CODE &&
2615                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2616                 if (s2->progressive_sequence && !s2->progressive_frame) {
2617                     s2->progressive_frame = 1;
2618                     av_log(s2->avctx, AV_LOG_ERROR,
2619                            "interlaced frame in progressive sequence, ignoring\n");
2620                 }
2621
2622                 if (s2->picture_structure == 0 ||
2623                     (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2624                     av_log(s2->avctx, AV_LOG_ERROR,
2625                            "picture_structure %d invalid, ignoring\n",
2626                            s2->picture_structure);
2627                     s2->picture_structure = PICT_FRAME;
2628                 }
2629
2630                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2631                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2632
2633                 if (s2->picture_structure == PICT_FRAME) {
2634                     s2->first_field = 0;
2635                     s2->v_edge_pos  = 16 * s2->mb_height;
2636                 } else {
2637                     s2->first_field ^= 1;
2638                     s2->v_edge_pos   = 8 * s2->mb_height;
2639                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2640                 }
2641             }
2642             if (start_code >= SLICE_MIN_START_CODE &&
2643                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2644                 const int field_pic = s2->picture_structure != PICT_FRAME;
2645                 int mb_y = start_code - SLICE_MIN_START_CODE;
2646                 last_code = SLICE_MIN_START_CODE;
2647                 if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2648                     mb_y += (*buf_ptr&0xE0)<<2;
2649
2650                 mb_y <<= field_pic;
2651                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2652                     mb_y++;
2653
2654                 if (buf_end - buf_ptr < 2) {
2655                     av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
2656                     return AVERROR_INVALIDDATA;
2657                 }
2658
2659                 if (mb_y >= s2->mb_height) {
2660                     av_log(s2->avctx, AV_LOG_ERROR,
2661                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2662                     return AVERROR_INVALIDDATA;
2663                 }
2664
2665                 if (!s2->last_picture_ptr) {
2666                     /* Skip B-frames if we do not have reference frames and
2667                      * GOP is not closed. */
2668                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2669                         if (!s2->closed_gop) {
2670                             skip_frame = 1;
2671                             break;
2672                         }
2673                     }
2674                 }
2675                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->avctx->flags2 & AV_CODEC_FLAG2_SHOW_ALL))
2676                     s->sync = 1;
2677                 if (!s2->next_picture_ptr) {
2678                     /* Skip P-frames if we do not have a reference frame or
2679                      * we have an invalid header. */
2680                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2681                         skip_frame = 1;
2682                         break;
2683                     }
2684                 }
2685                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2686                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2687                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2688                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2689                     avctx->skip_frame >= AVDISCARD_ALL) {
2690                     skip_frame = 1;
2691                     break;
2692                 }
2693
2694                 if (!s->mpeg_enc_ctx_allocated)
2695                     break;
2696
2697                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2698                     if (mb_y < avctx->skip_top ||
2699                         mb_y >= s2->mb_height - avctx->skip_bottom)
2700                         break;
2701                 }
2702
2703                 if (!s2->pict_type) {
2704                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2705                     if (avctx->err_recognition & AV_EF_EXPLODE)
2706                         return AVERROR_INVALIDDATA;
2707                     break;
2708                 }
2709
2710                 if (s->first_slice) {
2711                     skip_frame     = 0;
2712                     s->first_slice = 0;
2713                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2714                         return ret;
2715                 }
2716                 if (!s2->current_picture_ptr) {
2717                     av_log(avctx, AV_LOG_ERROR,
2718                            "current_picture not initialized\n");
2719                     return AVERROR_INVALIDDATA;
2720                 }
2721
2722 #if FF_API_VDPAU
2723                 if (uses_vdpau(avctx)) {
2724                     s->slice_count++;
2725                     break;
2726                 }
2727 #endif
2728
2729                 if (HAVE_THREADS &&
2730                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2731                     !avctx->hwaccel) {
2732                     int threshold = (s2->mb_height * s->slice_count +
2733                                      s2->slice_context_count / 2) /
2734                                     s2->slice_context_count;
2735                     av_assert0(avctx->thread_count > 1);
2736                     if (threshold <= mb_y) {
2737                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2738
2739                         thread_context->start_mb_y = mb_y;
2740                         thread_context->end_mb_y   = s2->mb_height;
2741                         if (s->slice_count) {
2742                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2743                             ret = ff_update_duplicate_context(thread_context, s2);
2744                             if (ret < 0)
2745                                 return ret;
2746                         }
2747                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2748                         s->slice_count++;
2749                     }
2750                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2751                 } else {
2752                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2753                     emms_c();
2754
2755                     if (ret < 0) {
2756                         if (avctx->err_recognition & AV_EF_EXPLODE)
2757                             return ret;
2758                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2759                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2760                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2761                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2762                     } else {
2763                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2764                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2765                                         ER_AC_END | ER_DC_END | ER_MV_END);
2766                     }
2767                 }
2768             }
2769             break;
2770         }
2771     }
2772 }
2773
2774 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2775                              int *got_output, AVPacket *avpkt)
2776 {
2777     const uint8_t *buf = avpkt->data;
2778     int ret;
2779     int buf_size = avpkt->size;
2780     Mpeg1Context *s = avctx->priv_data;
2781     AVFrame *picture = data;
2782     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2783
2784     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2785         /* special case for last picture */
2786         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2787             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2788             if (ret < 0)
2789                 return ret;
2790
2791             s2->next_picture_ptr = NULL;
2792
2793             *got_output = 1;
2794         }
2795         return buf_size;
2796     }
2797
2798     if (s2->avctx->flags & AV_CODEC_FLAG_TRUNCATED) {
2799         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2800                                            buf_size, NULL);
2801
2802         if (ff_combine_frame(&s2->parse_context, next,
2803                              (const uint8_t **) &buf, &buf_size) < 0)
2804             return buf_size;
2805     }
2806
2807     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2808     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2809                                            || s2->codec_tag == AV_RL32("BW10")
2810                                           ))
2811         vcr2_init_sequence(avctx);
2812
2813     s->slice_count = 0;
2814
2815     if (avctx->extradata && !s->extradata_decoded) {
2816         ret = decode_chunks(avctx, picture, got_output,
2817                             avctx->extradata, avctx->extradata_size);
2818         if (*got_output) {
2819             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2820             *got_output = 0;
2821         }
2822         s->extradata_decoded = 1;
2823         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
2824             s2->current_picture_ptr = NULL;
2825             return ret;
2826         }
2827     }
2828
2829     ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
2830     if (ret<0 || *got_output)
2831         s2->current_picture_ptr = NULL;
2832
2833     return ret;
2834 }
2835
2836 static void flush(AVCodecContext *avctx)
2837 {
2838     Mpeg1Context *s = avctx->priv_data;
2839
2840     s->sync       = 0;
2841
2842     ff_mpeg_flush(avctx);
2843 }
2844
2845 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2846 {
2847     Mpeg1Context *s = avctx->priv_data;
2848
2849     if (s->mpeg_enc_ctx_allocated)
2850         ff_mpv_common_end(&s->mpeg_enc_ctx);
2851     av_freep(&s->a53_caption);
2852     return 0;
2853 }
2854
2855 static const AVProfile mpeg2_video_profiles[] = {
2856     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2857     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2858     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2859     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2860     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2861     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2862     { FF_PROFILE_RESERVED,           "Reserved"           },
2863     { FF_PROFILE_RESERVED,           "Reserved"           },
2864     { FF_PROFILE_UNKNOWN                                  },
2865 };
2866
2867 AVCodec ff_mpeg1video_decoder = {
2868     .name                  = "mpeg1video",
2869     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2870     .type                  = AVMEDIA_TYPE_VIDEO,
2871     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2872     .priv_data_size        = sizeof(Mpeg1Context),
2873     .init                  = mpeg_decode_init,
2874     .close                 = mpeg_decode_end,
2875     .decode                = mpeg_decode_frame,
2876     .capabilities          = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2877                              AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2878                              AV_CODEC_CAP_SLICE_THREADS,
2879     .flush                 = flush,
2880     .max_lowres            = 3,
2881     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2882 };
2883
2884 AVCodec ff_mpeg2video_decoder = {
2885     .name           = "mpeg2video",
2886     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2887     .type           = AVMEDIA_TYPE_VIDEO,
2888     .id             = AV_CODEC_ID_MPEG2VIDEO,
2889     .priv_data_size = sizeof(Mpeg1Context),
2890     .init           = mpeg_decode_init,
2891     .close          = mpeg_decode_end,
2892     .decode         = mpeg_decode_frame,
2893     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2894                       AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY |
2895                       AV_CODEC_CAP_SLICE_THREADS,
2896     .flush          = flush,
2897     .max_lowres     = 3,
2898     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2899 };
2900
2901 //legacy decoder
2902 AVCodec ff_mpegvideo_decoder = {
2903     .name           = "mpegvideo",
2904     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2905     .type           = AVMEDIA_TYPE_VIDEO,
2906     .id             = AV_CODEC_ID_MPEG2VIDEO,
2907     .priv_data_size = sizeof(Mpeg1Context),
2908     .init           = mpeg_decode_init,
2909     .close          = mpeg_decode_end,
2910     .decode         = mpeg_decode_frame,
2911     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED | AV_CODEC_CAP_DELAY | AV_CODEC_CAP_SLICE_THREADS,
2912     .flush          = flush,
2913     .max_lowres     = 3,
2914 };
2915
2916 #if FF_API_XVMC
2917 #if CONFIG_MPEG_XVMC_DECODER
2918 FF_DISABLE_DEPRECATION_WARNINGS
2919 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2920 {
2921     if (avctx->active_thread_type & FF_THREAD_SLICE)
2922         return -1;
2923     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2924         return -1;
2925     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2926         ff_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2927     }
2928     mpeg_decode_init(avctx);
2929
2930     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2931     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2932
2933     return 0;
2934 }
2935
2936 AVCodec ff_mpeg_xvmc_decoder = {
2937     .name           = "mpegvideo_xvmc",
2938     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2939     .type           = AVMEDIA_TYPE_VIDEO,
2940     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2941     .priv_data_size = sizeof(Mpeg1Context),
2942     .init           = mpeg_mc_decode_init,
2943     .close          = mpeg_decode_end,
2944     .decode         = mpeg_decode_frame,
2945     .capabilities   = AV_CODEC_CAP_DRAW_HORIZ_BAND | AV_CODEC_CAP_DR1 |
2946                       AV_CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL |
2947                       AV_CODEC_CAP_DELAY,
2948     .flush          = flush,
2949 };
2950 FF_ENABLE_DEPRECATION_WARNINGS
2951 #endif
2952 #endif /* FF_API_XVMC */
2953
2954 #if CONFIG_MPEG_VDPAU_DECODER && FF_API_VDPAU
2955 AVCodec ff_mpeg_vdpau_decoder = {
2956     .name           = "mpegvideo_vdpau",
2957     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2958     .type           = AVMEDIA_TYPE_VIDEO,
2959     .id             = AV_CODEC_ID_MPEG2VIDEO,
2960     .priv_data_size = sizeof(Mpeg1Context),
2961     .init           = mpeg_decode_init,
2962     .close          = mpeg_decode_end,
2963     .decode         = mpeg_decode_frame,
2964     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED |
2965                       AV_CODEC_CAP_HWACCEL_VDPAU | AV_CODEC_CAP_DELAY,
2966     .flush          = flush,
2967 };
2968 #endif
2969
2970 #if CONFIG_MPEG1_VDPAU_DECODER && FF_API_VDPAU
2971 AVCodec ff_mpeg1_vdpau_decoder = {
2972     .name           = "mpeg1video_vdpau",
2973     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2974     .type           = AVMEDIA_TYPE_VIDEO,
2975     .id             = AV_CODEC_ID_MPEG1VIDEO,
2976     .priv_data_size = sizeof(Mpeg1Context),
2977     .init           = mpeg_decode_init,
2978     .close          = mpeg_decode_end,
2979     .decode         = mpeg_decode_frame,
2980     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_TRUNCATED |
2981                       AV_CODEC_CAP_HWACCEL_VDPAU | AV_CODEC_CAP_DELAY,
2982     .flush          = flush,
2983 };
2984 #endif