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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 "thread.h"
  47 #include "version.h"
  48 #include "vdpau_compat.h"
  49 #include "xvmc_internal.h"
  50
  51 typedef struct Mpeg1Context {
  52     MpegEncContext mpeg_enc_ctx;
  53     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  54     int repeat_field;           /* true if we must repeat the field */
  55     AVPanScan pan_scan;         /* some temporary storage for the panscan */
  56     AVStereo3D stereo3d;
  57     int has_stereo3d;
  58     uint8_t *a53_caption;
  59     int a53_caption_size;
  60     uint8_t afd;
  61     int has_afd;
  62     int slice_count;
  63     AVRational save_aspect;
  64     int save_width, save_height, save_progressive_seq;
  65     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
  66     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
  67     int tmpgexs;
  68     int first_slice;
  69     int extradata_decoded;
  70 } Mpeg1Context;
  71
  72 #define MB_TYPE_ZERO_MV   0x20000000
  73
  74 static const uint32_t ptype2mb_type[7] = {
  75                     MB_TYPE_INTRA,
  76                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  77                     MB_TYPE_L0,
  78                     MB_TYPE_L0 | MB_TYPE_CBP,
  79     MB_TYPE_QUANT | MB_TYPE_INTRA,
  80     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  81     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
  82 };
  83
  84 static const uint32_t btype2mb_type[11] = {
  85                     MB_TYPE_INTRA,
  86                     MB_TYPE_L1,
  87                     MB_TYPE_L1   | MB_TYPE_CBP,
  88                     MB_TYPE_L0,
  89                     MB_TYPE_L0   | MB_TYPE_CBP,
  90                     MB_TYPE_L0L1,
  91                     MB_TYPE_L0L1 | MB_TYPE_CBP,
  92     MB_TYPE_QUANT | MB_TYPE_INTRA,
  93     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
  94     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
  95     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
  96 };
  97
  98 static const uint8_t non_linear_qscale[32] = {
  99      0,  1,  2,  3,  4,  5,   6,   7,
 100      8, 10, 12, 14, 16, 18,  20,  22,
 101     24, 28, 32, 36, 40, 44,  48,  52,
 102     56, 64, 72, 80, 88, 96, 104, 112,
 103 };
 104
 105 /* as H.263, but only 17 codes */
 106 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 107 {
 108     int code, sign, val, shift;
 109
 110     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
 111     if (code == 0)
 112         return pred;
 113     if (code < 0)
 114         return 0xffff;
 115
 116     sign  = get_bits1(&s->gb);
 117     shift = fcode - 1;
 118     val   = code;
 119     if (shift) {
 120         val  = (val - 1) << shift;
 121         val |= get_bits(&s->gb, shift);
 122         val++;
 123     }
 124     if (sign)
 125         val = -val;
 126     val += pred;
 127
 128     /* modulo decoding */
 129     return sign_extend(val, 5 + shift);
 130 }
 131
 132 #define check_scantable_index(ctx, x)                                         \
 133     do {                                                                      \
 134         if ((x) > 63) {                                                       \
 135             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
 136                    ctx->mb_x, ctx->mb_y);                                     \
 137             return AVERROR_INVALIDDATA;                                       \
 138         }                                                                     \
 139     } while (0)
 140
 141 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
 142                                            int16_t *block, int n)
 143 {
 144     int level, dc, diff, i, j, run;
 145     int component;
 146     RLTable *rl                  = &ff_rl_mpeg1;
 147     uint8_t *const scantable     = s->intra_scantable.permutated;
 148     const uint16_t *quant_matrix = s->intra_matrix;
 149     const int qscale             = s->qscale;
 150
 151     /* DC coefficient */
 152     component = (n <= 3 ? 0 : n - 4 + 1);
 153     diff = decode_dc(&s->gb, component);
 154     if (diff >= 0xffff)
 155         return AVERROR_INVALIDDATA;
 156     dc  = s->last_dc[component];
 157     dc += diff;
 158     s->last_dc[component] = dc;
 159     block[0] = dc * quant_matrix[0];
 160     ff_tlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
 161     i = 0;
 162     {
 163         OPEN_READER(re, &s->gb);
 164         UPDATE_CACHE(re, &s->gb);
 165         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 166             goto end;
 167
 168         /* now quantify & encode AC coefficients */
 169         for (;;) {
 170             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 171                        TEX_VLC_BITS, 2, 0);
 172
 173             if (level != 0) {
 174                 i += run;
 175                 check_scantable_index(s, i);
 176                 j = scantable[i];
 177                 level = (level * qscale * quant_matrix[j]) >> 4;
 178                 level = (level - 1) | 1;
 179                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 180                         SHOW_SBITS(re, &s->gb, 1);
 181                 SKIP_BITS(re, &s->gb, 1);
 182             } else {
 183                 /* escape */
 184                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 185                 LAST_SKIP_BITS(re, &s->gb, 6);
 186                 UPDATE_CACHE(re, &s->gb);
 187                 level = SHOW_SBITS(re, &s->gb, 8);
 188                 SKIP_BITS(re, &s->gb, 8);
 189                 if (level == -128) {
 190                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 191                     SKIP_BITS(re, &s->gb, 8);
 192                 } else if (level == 0) {
 193                     level = SHOW_UBITS(re, &s->gb, 8);
 194                     SKIP_BITS(re, &s->gb, 8);
 195                 }
 196                 i += run;
 197                 check_scantable_index(s, i);
 198                 j = scantable[i];
 199                 if (level < 0) {
 200                     level = -level;
 201                     level = (level * qscale * quant_matrix[j]) >> 4;
 202                     level = (level - 1) | 1;
 203                     level = -level;
 204                 } else {
 205                     level = (level * qscale * quant_matrix[j]) >> 4;
 206                     level = (level - 1) | 1;
 207                 }
 208             }
 209
 210             block[j] = level;
 211             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 212                break;
 213
 214             UPDATE_CACHE(re, &s->gb);
 215         }
 216 end:
 217         LAST_SKIP_BITS(re, &s->gb, 2);
 218         CLOSE_READER(re, &s->gb);
 219     }
 220     s->block_last_index[n] = i;
 221     return 0;
 222 }
 223
 224 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 225 {
 226     return mpeg1_decode_block_intra(s, block, n);
 227 }
 228
 229 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 230                                            int16_t *block, int n)
 231 {
 232     int level, i, j, run;
 233     RLTable *rl                  = &ff_rl_mpeg1;
 234     uint8_t *const scantable     = s->intra_scantable.permutated;
 235     const uint16_t *quant_matrix = s->inter_matrix;
 236     const int qscale             = s->qscale;
 237
 238     {
 239         OPEN_READER(re, &s->gb);
 240         i = -1;
 241         // special case for first coefficient, no need to add second VLC table
 242         UPDATE_CACHE(re, &s->gb);
 243         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 244             level = (3 * qscale * quant_matrix[0]) >> 5;
 245             level = (level - 1) | 1;
 246             if (GET_CACHE(re, &s->gb) & 0x40000000)
 247                 level = -level;
 248             block[0] = level;
 249             i++;
 250             SKIP_BITS(re, &s->gb, 2);
 251             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 252                 goto end;
 253         }
 254         /* now quantify & encode AC coefficients */
 255         for (;;) {
 256             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 257                        TEX_VLC_BITS, 2, 0);
 258
 259             if (level != 0) {
 260                 i += run;
 261                 check_scantable_index(s, i);
 262                 j = scantable[i];
 263                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 264                 level = (level - 1) | 1;
 265                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 266                         SHOW_SBITS(re, &s->gb, 1);
 267                 SKIP_BITS(re, &s->gb, 1);
 268             } else {
 269                 /* escape */
 270                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 271                 LAST_SKIP_BITS(re, &s->gb, 6);
 272                 UPDATE_CACHE(re, &s->gb);
 273                 level = SHOW_SBITS(re, &s->gb, 8);
 274                 SKIP_BITS(re, &s->gb, 8);
 275                 if (level == -128) {
 276                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 277                     SKIP_BITS(re, &s->gb, 8);
 278                 } else if (level == 0) {
 279                     level = SHOW_UBITS(re, &s->gb, 8);
 280                     SKIP_BITS(re, &s->gb, 8);
 281                 }
 282                 i += run;
 283                 check_scantable_index(s, i);
 284                 j = scantable[i];
 285                 if (level < 0) {
 286                     level = -level;
 287                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 288                     level = (level - 1) | 1;
 289                     level = -level;
 290                 } else {
 291                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 292                     level = (level - 1) | 1;
 293                 }
 294             }
 295
 296             block[j] = level;
 297             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 298                 break;
 299             UPDATE_CACHE(re, &s->gb);
 300         }
 301 end:
 302         LAST_SKIP_BITS(re, &s->gb, 2);
 303         CLOSE_READER(re, &s->gb);
 304     }
 305     s->block_last_index[n] = i;
 306     return 0;
 307 }
 308
 309 /**
 310  * Note: this function can read out of range and crash for corrupt streams.
 311  * Changing this would eat up any speed benefits it has.
 312  * Do not use "fast" flag if you need the code to be robust.
 313  */
 314 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
 315                                                 int16_t *block, int n)
 316 {
 317     int level, i, j, run;
 318     RLTable *rl              = &ff_rl_mpeg1;
 319     uint8_t *const scantable = s->intra_scantable.permutated;
 320     const int qscale         = s->qscale;
 321
 322     {
 323         OPEN_READER(re, &s->gb);
 324         i = -1;
 325         // Special case for first coefficient, no need to add second VLC table.
 326         UPDATE_CACHE(re, &s->gb);
 327         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 328             level = (3 * qscale) >> 1;
 329             level = (level - 1) | 1;
 330             if (GET_CACHE(re, &s->gb) & 0x40000000)
 331                 level = -level;
 332             block[0] = level;
 333             i++;
 334             SKIP_BITS(re, &s->gb, 2);
 335             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 336                 goto end;
 337         }
 338
 339         /* now quantify & encode AC coefficients */
 340         for (;;) {
 341             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 342                        TEX_VLC_BITS, 2, 0);
 343
 344             if (level != 0) {
 345                 i += run;
 346                 check_scantable_index(s, i);
 347                 j = scantable[i];
 348                 level = ((level * 2 + 1) * qscale) >> 1;
 349                 level = (level - 1) | 1;
 350                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 351                         SHOW_SBITS(re, &s->gb, 1);
 352                 SKIP_BITS(re, &s->gb, 1);
 353             } else {
 354                 /* escape */
 355                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 356                 LAST_SKIP_BITS(re, &s->gb, 6);
 357                 UPDATE_CACHE(re, &s->gb);
 358                 level = SHOW_SBITS(re, &s->gb, 8);
 359                 SKIP_BITS(re, &s->gb, 8);
 360                 if (level == -128) {
 361                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 362                     SKIP_BITS(re, &s->gb, 8);
 363                 } else if (level == 0) {
 364                     level = SHOW_UBITS(re, &s->gb, 8);
 365                     SKIP_BITS(re, &s->gb, 8);
 366                 }
 367                 i += run;
 368                 check_scantable_index(s, i);
 369                 j = scantable[i];
 370                 if (level < 0) {
 371                     level = -level;
 372                     level = ((level * 2 + 1) * qscale) >> 1;
 373                     level = (level - 1) | 1;
 374                     level = -level;
 375                 } else {
 376                     level = ((level * 2 + 1) * qscale) >> 1;
 377                     level = (level - 1) | 1;
 378                 }
 379             }
 380
 381             block[j] = level;
 382             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 383                 break;
 384             UPDATE_CACHE(re, &s->gb);
 385         }
 386 end:
 387         LAST_SKIP_BITS(re, &s->gb, 2);
 388         CLOSE_READER(re, &s->gb);
 389     }
 390     s->block_last_index[n] = i;
 391     return 0;
 392 }
 393
 394 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 395                                                int16_t *block, int n)
 396 {
 397     int level, i, j, run;
 398     RLTable *rl = &ff_rl_mpeg1;
 399     uint8_t *const scantable = s->intra_scantable.permutated;
 400     const uint16_t *quant_matrix;
 401     const int qscale = s->qscale;
 402     int mismatch;
 403
 404     mismatch = 1;
 405
 406     {
 407         OPEN_READER(re, &s->gb);
 408         i = -1;
 409         if (n < 4)
 410             quant_matrix = s->inter_matrix;
 411         else
 412             quant_matrix = s->chroma_inter_matrix;
 413
 414         // Special case for first coefficient, no need to add second VLC table.
 415         UPDATE_CACHE(re, &s->gb);
 416         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 417             level = (3 * qscale * quant_matrix[0]) >> 5;
 418             if (GET_CACHE(re, &s->gb) & 0x40000000)
 419                 level = -level;
 420             block[0]  = level;
 421             mismatch ^= level;
 422             i++;
 423             SKIP_BITS(re, &s->gb, 2);
 424             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 425                 goto end;
 426         }
 427
 428         /* now quantify & encode AC coefficients */
 429         for (;;) {
 430             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 431                        TEX_VLC_BITS, 2, 0);
 432
 433             if (level != 0) {
 434                 i += run;
 435                 check_scantable_index(s, i);
 436                 j = scantable[i];
 437                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 438                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 439                         SHOW_SBITS(re, &s->gb, 1);
 440                 SKIP_BITS(re, &s->gb, 1);
 441             } else {
 442                 /* escape */
 443                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 444                 LAST_SKIP_BITS(re, &s->gb, 6);
 445                 UPDATE_CACHE(re, &s->gb);
 446                 level = SHOW_SBITS(re, &s->gb, 12);
 447                 SKIP_BITS(re, &s->gb, 12);
 448
 449                 i += run;
 450                 check_scantable_index(s, i);
 451                 j = scantable[i];
 452                 if (level < 0) {
 453                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 454                     level = -level;
 455                 } else {
 456                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 457                 }
 458             }
 459
 460             mismatch ^= level;
 461             block[j]  = level;
 462             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 463                 break;
 464             UPDATE_CACHE(re, &s->gb);
 465         }
 466 end:
 467         LAST_SKIP_BITS(re, &s->gb, 2);
 468         CLOSE_READER(re, &s->gb);
 469     }
 470     block[63] ^= (mismatch & 1);
 471
 472     s->block_last_index[n] = i;
 473     return 0;
 474 }
 475
 476 /**
 477  * Note: this function can read out of range and crash for corrupt streams.
 478  * Changing this would eat up any speed benefits it has.
 479  * Do not use "fast" flag if you need the code to be robust.
 480  */
 481 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 482                                                     int16_t *block, int n)
 483 {
 484     int level, i, j, run;
 485     RLTable *rl              = &ff_rl_mpeg1;
 486     uint8_t *const scantable = s->intra_scantable.permutated;
 487     const int qscale         = s->qscale;
 488     OPEN_READER(re, &s->gb);
 489     i = -1;
 490
 491     // special case for first coefficient, no need to add second VLC table
 492     UPDATE_CACHE(re, &s->gb);
 493     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 494         level = (3 * qscale) >> 1;
 495         if (GET_CACHE(re, &s->gb) & 0x40000000)
 496             level = -level;
 497         block[0] = level;
 498         i++;
 499         SKIP_BITS(re, &s->gb, 2);
 500         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 501             goto end;
 502     }
 503
 504     /* now quantify & encode AC coefficients */
 505     for (;;) {
 506         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 507
 508         if (level != 0) {
 509             i += run;
 510             j = scantable[i];
 511             level = ((level * 2 + 1) * qscale) >> 1;
 512             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 513                     SHOW_SBITS(re, &s->gb, 1);
 514             SKIP_BITS(re, &s->gb, 1);
 515         } else {
 516             /* escape */
 517             run = SHOW_UBITS(re, &s->gb, 6) + 1;
 518             LAST_SKIP_BITS(re, &s->gb, 6);
 519             UPDATE_CACHE(re, &s->gb);
 520             level = SHOW_SBITS(re, &s->gb, 12);
 521             SKIP_BITS(re, &s->gb, 12);
 522
 523             i += run;
 524             j = scantable[i];
 525             if (level < 0) {
 526                 level = ((-level * 2 + 1) * qscale) >> 1;
 527                 level = -level;
 528             } else {
 529                 level = ((level * 2 + 1) * qscale) >> 1;
 530             }
 531         }
 532
 533         block[j] = level;
 534         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
 535             break;
 536
 537         UPDATE_CACHE(re, &s->gb);
 538     }
 539 end:
 540     LAST_SKIP_BITS(re, &s->gb, 2);
 541     CLOSE_READER(re, &s->gb);
 542     s->block_last_index[n] = i;
 543     return 0;
 544 }
 545
 546 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
 547                                            int16_t *block, int n)
 548 {
 549     int level, dc, diff, i, j, run;
 550     int component;
 551     RLTable *rl;
 552     uint8_t *const scantable = s->intra_scantable.permutated;
 553     const uint16_t *quant_matrix;
 554     const int qscale = s->qscale;
 555     int mismatch;
 556
 557     /* DC coefficient */
 558     if (n < 4) {
 559         quant_matrix = s->intra_matrix;
 560         component    = 0;
 561     } else {
 562         quant_matrix = s->chroma_intra_matrix;
 563         component    = (n & 1) + 1;
 564     }
 565     diff = decode_dc(&s->gb, component);
 566     if (diff >= 0xffff)
 567         return AVERROR_INVALIDDATA;
 568     dc  = s->last_dc[component];
 569     dc += diff;
 570     s->last_dc[component] = dc;
 571     block[0] = dc << (3 - s->intra_dc_precision);
 572     ff_tlog(s->avctx, "dc=%d\n", block[0]);
 573     mismatch = block[0] ^ 1;
 574     i = 0;
 575     if (s->intra_vlc_format)
 576         rl = &ff_rl_mpeg2;
 577     else
 578         rl = &ff_rl_mpeg1;
 579
 580     {
 581         OPEN_READER(re, &s->gb);
 582         /* now quantify & encode AC coefficients */
 583         for (;;) {
 584             UPDATE_CACHE(re, &s->gb);
 585             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 586                        TEX_VLC_BITS, 2, 0);
 587
 588             if (level == 127) {
 589                 break;
 590             } else if (level != 0) {
 591                 i += run;
 592                 check_scantable_index(s, i);
 593                 j = scantable[i];
 594                 level = (level * qscale * quant_matrix[j]) >> 4;
 595                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 596                         SHOW_SBITS(re, &s->gb, 1);
 597                 LAST_SKIP_BITS(re, &s->gb, 1);
 598             } else {
 599                 /* escape */
 600                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 601                 LAST_SKIP_BITS(re, &s->gb, 6);
 602                 UPDATE_CACHE(re, &s->gb);
 603                 level = SHOW_SBITS(re, &s->gb, 12);
 604                 SKIP_BITS(re, &s->gb, 12);
 605                 i += run;
 606                 check_scantable_index(s, i);
 607                 j = scantable[i];
 608                 if (level < 0) {
 609                     level = (-level * qscale * quant_matrix[j]) >> 4;
 610                     level = -level;
 611                 } else {
 612                     level = (level * qscale * quant_matrix[j]) >> 4;
 613                 }
 614             }
 615
 616             mismatch ^= level;
 617             block[j]  = level;
 618         }
 619         CLOSE_READER(re, &s->gb);
 620     }
 621     block[63] ^= mismatch & 1;
 622
 623     s->block_last_index[n] = i;
 624     return 0;
 625 }
 626
 627 /**
 628  * Note: this function can read out of range and crash for corrupt streams.
 629  * Changing this would eat up any speed benefits it has.
 630  * Do not use "fast" flag if you need the code to be robust.
 631  */
 632 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
 633                                                 int16_t *block, int n)
 634 {
 635     int level, dc, diff, i, j, run;
 636     int component;
 637     RLTable *rl;
 638     uint8_t *const scantable = s->intra_scantable.permutated;
 639     const uint16_t *quant_matrix;
 640     const int qscale = s->qscale;
 641
 642     /* DC coefficient */
 643     if (n < 4) {
 644         quant_matrix = s->intra_matrix;
 645         component    = 0;
 646     } else {
 647         quant_matrix = s->chroma_intra_matrix;
 648         component    = (n & 1) + 1;
 649     }
 650     diff = decode_dc(&s->gb, component);
 651     if (diff >= 0xffff)
 652         return AVERROR_INVALIDDATA;
 653     dc = s->last_dc[component];
 654     dc += diff;
 655     s->last_dc[component] = dc;
 656     block[0] = dc << (3 - s->intra_dc_precision);
 657     i = 0;
 658     if (s->intra_vlc_format)
 659         rl = &ff_rl_mpeg2;
 660     else
 661         rl = &ff_rl_mpeg1;
 662
 663     {
 664         OPEN_READER(re, &s->gb);
 665         /* now quantify & encode AC coefficients */
 666         for (;;) {
 667             UPDATE_CACHE(re, &s->gb);
 668             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 669                        TEX_VLC_BITS, 2, 0);
 670
 671             if (level >= 64 || i > 63) {
 672                 break;
 673             } else if (level != 0) {
 674                 i += run;
 675                 j = scantable[i];
 676                 level = (level * qscale * quant_matrix[j]) >> 4;
 677                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 678                         SHOW_SBITS(re, &s->gb, 1);
 679                 LAST_SKIP_BITS(re, &s->gb, 1);
 680             } else {
 681                 /* escape */
 682                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 683                 LAST_SKIP_BITS(re, &s->gb, 6);
 684                 UPDATE_CACHE(re, &s->gb);
 685                 level = SHOW_SBITS(re, &s->gb, 12);
 686                 SKIP_BITS(re, &s->gb, 12);
 687                 i += run;
 688                 j = scantable[i];
 689                 if (level < 0) {
 690                     level = (-level * qscale * quant_matrix[j]) >> 4;
 691                     level = -level;
 692                 } else {
 693                     level = (level * qscale * quant_matrix[j]) >> 4;
 694                 }
 695             }
 696
 697             block[j] = level;
 698         }
 699         CLOSE_READER(re, &s->gb);
 700     }
 701
 702     s->block_last_index[n] = i;
 703     return 0;
 704 }
 705
 706 /******************************************/
 707 /* decoding */
 708
 709 static inline int get_dmv(MpegEncContext *s)
 710 {
 711     if (get_bits1(&s->gb))
 712         return 1 - (get_bits1(&s->gb) << 1);
 713     else
 714         return 0;
 715 }
 716
 717 static inline int get_qscale(MpegEncContext *s)
 718 {
 719     int qscale = get_bits(&s->gb, 5);
 720     if (s->q_scale_type)
 721         return non_linear_qscale[qscale];
 722     else
 723         return qscale << 1;
 724 }
 725
 726
 727 /* motion type (for MPEG-2) */
 728 #define MT_FIELD 1
 729 #define MT_FRAME 2
 730 #define MT_16X8  2
 731 #define MT_DMV   3
 732
 733 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 734 {
 735     int i, j, k, cbp, val, mb_type, motion_type;
 736     const int mb_block_count = 4 + (1 << s->chroma_format);
 737     int ret;
 738
 739     ff_tlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 740
 741     av_assert2(s->mb_skipped == 0);
 742
 743     if (s->mb_skip_run-- != 0) {
 744         if (s->pict_type == AV_PICTURE_TYPE_P) {
 745             s->mb_skipped = 1;
 746             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 747                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 748         } else {
 749             int mb_type;
 750
 751             if (s->mb_x)
 752                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 753             else
 754                 // FIXME not sure if this is allowed in MPEG at all
 755                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
 756             if (IS_INTRA(mb_type)) {
 757                 av_log(s->avctx, AV_LOG_ERROR, "skip with previntra\n");
 758                 return AVERROR_INVALIDDATA;
 759             }
 760             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 761                 mb_type | MB_TYPE_SKIP;
 762
 763             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 764                 s->mb_skipped = 1;
 765         }
 766
 767         return 0;
 768     }
 769
 770     switch (s->pict_type) {
 771     default:
 772     case AV_PICTURE_TYPE_I:
 773         if (get_bits1(&s->gb) == 0) {
 774             if (get_bits1(&s->gb) == 0) {
 775                 av_log(s->avctx, AV_LOG_ERROR,
 776                        "invalid mb type in I Frame at %d %d\n",
 777                        s->mb_x, s->mb_y);
 778                 return AVERROR_INVALIDDATA;
 779             }
 780             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 781         } else {
 782             mb_type = MB_TYPE_INTRA;
 783         }
 784         break;
 785     case AV_PICTURE_TYPE_P:
 786         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 787         if (mb_type < 0) {
 788             av_log(s->avctx, AV_LOG_ERROR,
 789                    "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 790             return AVERROR_INVALIDDATA;
 791         }
 792         mb_type = ptype2mb_type[mb_type];
 793         break;
 794     case AV_PICTURE_TYPE_B:
 795         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 796         if (mb_type < 0) {
 797             av_log(s->avctx, AV_LOG_ERROR,
 798                    "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 799             return AVERROR_INVALIDDATA;
 800         }
 801         mb_type = btype2mb_type[mb_type];
 802         break;
 803     }
 804     ff_tlog(s->avctx, "mb_type=%x\n", mb_type);
 805 //    motion_type = 0; /* avoid warning */
 806     if (IS_INTRA(mb_type)) {
 807         s->bdsp.clear_blocks(s->block[0]);
 808
 809         if (!s->chroma_y_shift)
 810             s->bdsp.clear_blocks(s->block[6]);
 811
 812         /* compute DCT type */
 813         // FIXME: add an interlaced_dct coded var?
 814         if (s->picture_structure == PICT_FRAME &&
 815             !s->frame_pred_frame_dct)
 816             s->interlaced_dct = get_bits1(&s->gb);
 817
 818         if (IS_QUANT(mb_type))
 819             s->qscale = get_qscale(s);
 820
 821         if (s->concealment_motion_vectors) {
 822             /* just parse them */
 823             if (s->picture_structure != PICT_FRAME)
 824                 skip_bits1(&s->gb);  /* field select */
 825
 826             s->mv[0][0][0]      =
 827             s->last_mv[0][0][0] =
 828             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
 829                                                      s->last_mv[0][0][0]);
 830             s->mv[0][0][1]      =
 831             s->last_mv[0][0][1] =
 832             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
 833                                                      s->last_mv[0][0][1]);
 834
 835             check_marker(&s->gb, "after concealment_motion_vectors");
 836         } else {
 837             /* reset mv prediction */
 838             memset(s->last_mv, 0, sizeof(s->last_mv));
 839         }
 840         s->mb_intra = 1;
 841         // if 1, we memcpy blocks in xvmcvideo
 842         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
 843             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 844
 845         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 846             if (s->avctx->flags2 & CODEC_FLAG2_FAST) {
 847                 for (i = 0; i < 6; i++)
 848                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 849             } else {
 850                 for (i = 0; i < mb_block_count; i++)
 851                     if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 852                         return ret;
 853             }
 854         } else {
 855             for (i = 0; i < 6; i++)
 856                 if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 857                     return ret;
 858         }
 859     } else {
 860         if (mb_type & MB_TYPE_ZERO_MV) {
 861             av_assert2(mb_type & MB_TYPE_CBP);
 862
 863             s->mv_dir = MV_DIR_FORWARD;
 864             if (s->picture_structure == PICT_FRAME) {
 865                 if (s->picture_structure == PICT_FRAME
 866                     && !s->frame_pred_frame_dct)
 867                     s->interlaced_dct = get_bits1(&s->gb);
 868                 s->mv_type = MV_TYPE_16X16;
 869             } else {
 870                 s->mv_type            = MV_TYPE_FIELD;
 871                 mb_type              |= MB_TYPE_INTERLACED;
 872                 s->field_select[0][0] = s->picture_structure - 1;
 873             }
 874
 875             if (IS_QUANT(mb_type))
 876                 s->qscale = get_qscale(s);
 877
 878             s->last_mv[0][0][0] = 0;
 879             s->last_mv[0][0][1] = 0;
 880             s->last_mv[0][1][0] = 0;
 881             s->last_mv[0][1][1] = 0;
 882             s->mv[0][0][0]      = 0;
 883             s->mv[0][0][1]      = 0;
 884         } else {
 885             av_assert2(mb_type & MB_TYPE_L0L1);
 886             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 887             /* get additional motion vector type */
 888             if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) {
 889                 motion_type = MT_FRAME;
 890             } else {
 891                 motion_type = get_bits(&s->gb, 2);
 892                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 893                     s->interlaced_dct = get_bits1(&s->gb);
 894             }
 895
 896             if (IS_QUANT(mb_type))
 897                 s->qscale = get_qscale(s);
 898
 899             /* motion vectors */
 900             s->mv_dir = (mb_type >> 13) & 3;
 901             ff_tlog(s->avctx, "motion_type=%d\n", motion_type);
 902             switch (motion_type) {
 903             case MT_FRAME: /* or MT_16X8 */
 904                 if (s->picture_structure == PICT_FRAME) {
 905                     mb_type   |= MB_TYPE_16x16;
 906                     s->mv_type = MV_TYPE_16X16;
 907                     for (i = 0; i < 2; i++) {
 908                         if (USES_LIST(mb_type, i)) {
 909                             /* MT_FRAME */
 910                             s->mv[i][0][0]      =
 911                             s->last_mv[i][0][0] =
 912                             s->last_mv[i][1][0] =
 913                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 914                                                    s->last_mv[i][0][0]);
 915                             s->mv[i][0][1]      =
 916                             s->last_mv[i][0][1] =
 917                             s->last_mv[i][1][1] =
 918                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 919                                                    s->last_mv[i][0][1]);
 920                             /* full_pel: only for MPEG-1 */
 921                             if (s->full_pel[i]) {
 922                                 s->mv[i][0][0] <<= 1;
 923                                 s->mv[i][0][1] <<= 1;
 924                             }
 925                         }
 926                     }
 927                 } else {
 928                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 929                     s->mv_type = MV_TYPE_16X8;
 930                     for (i = 0; i < 2; i++) {
 931                         if (USES_LIST(mb_type, i)) {
 932                             /* MT_16X8 */
 933                             for (j = 0; j < 2; j++) {
 934                                 s->field_select[i][j] = get_bits1(&s->gb);
 935                                 for (k = 0; k < 2; k++) {
 936                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 937                                                              s->last_mv[i][j][k]);
 938                                     s->last_mv[i][j][k] = val;
 939                                     s->mv[i][j][k]      = val;
 940                                 }
 941                             }
 942                         }
 943                     }
 944                 }
 945                 break;
 946             case MT_FIELD:
 947                 s->mv_type = MV_TYPE_FIELD;
 948                 if (s->picture_structure == PICT_FRAME) {
 949                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 950                     for (i = 0; i < 2; i++) {
 951                         if (USES_LIST(mb_type, i)) {
 952                             for (j = 0; j < 2; j++) {
 953                                 s->field_select[i][j] = get_bits1(&s->gb);
 954                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 955                                                          s->last_mv[i][j][0]);
 956                                 s->last_mv[i][j][0] = val;
 957                                 s->mv[i][j][0]      = val;
 958                                 ff_tlog(s->avctx, "fmx=%d\n", val);
 959                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 960                                                          s->last_mv[i][j][1] >> 1);
 961                                 s->last_mv[i][j][1] = 2 * val;
 962                                 s->mv[i][j][1]      = val;
 963                                 ff_tlog(s->avctx, "fmy=%d\n", val);
 964                             }
 965                         }
 966                     }
 967                 } else {
 968                     av_assert0(!s->progressive_sequence);
 969                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 970                     for (i = 0; i < 2; i++) {
 971                         if (USES_LIST(mb_type, i)) {
 972                             s->field_select[i][0] = get_bits1(&s->gb);
 973                             for (k = 0; k < 2; k++) {
 974                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 975                                                          s->last_mv[i][0][k]);
 976                                 s->last_mv[i][0][k] = val;
 977                                 s->last_mv[i][1][k] = val;
 978                                 s->mv[i][0][k]      = val;
 979                             }
 980                         }
 981                     }
 982                 }
 983                 break;
 984             case MT_DMV:
 985                 if (s->progressive_sequence){
 986                     av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
 987                     return AVERROR_INVALIDDATA;
 988                 }
 989                 s->mv_type = MV_TYPE_DMV;
 990                 for (i = 0; i < 2; i++) {
 991                     if (USES_LIST(mb_type, i)) {
 992                         int dmx, dmy, mx, my, m;
 993                         const int my_shift = s->picture_structure == PICT_FRAME;
 994
 995                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 996                                                 s->last_mv[i][0][0]);
 997                         s->last_mv[i][0][0] = mx;
 998                         s->last_mv[i][1][0] = mx;
 999                         dmx = get_dmv(s);
1000                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1001                                                  s->last_mv[i][0][1] >> my_shift);
1002                         dmy = get_dmv(s);
1003
1004
1005                         s->last_mv[i][0][1] = my << my_shift;
1006                         s->last_mv[i][1][1] = my << my_shift;
1007
1008                         s->mv[i][0][0] = mx;
1009                         s->mv[i][0][1] = my;
1010                         s->mv[i][1][0] = mx; // not used
1011                         s->mv[i][1][1] = my; // not used
1012
1013                         if (s->picture_structure == PICT_FRAME) {
1014                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1015
1016                             // m = 1 + 2 * s->top_field_first;
1017                             m = s->top_field_first ? 1 : 3;
1018
1019                             /* top -> top pred */
1020                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1021                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1022                             m = 4 - m;
1023                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1024                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1025                         } else {
1026                             mb_type |= MB_TYPE_16x16;
1027
1028                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1029                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1030                             if (s->picture_structure == PICT_TOP_FIELD)
1031                                 s->mv[i][2][1]--;
1032                             else
1033                                 s->mv[i][2][1]++;
1034                         }
1035                     }
1036                 }
1037                 break;
1038             default:
1039                 av_log(s->avctx, AV_LOG_ERROR,
1040                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1041                 return AVERROR_INVALIDDATA;
1042             }
1043         }
1044
1045         s->mb_intra = 0;
1046         if (HAS_CBP(mb_type)) {
1047             s->bdsp.clear_blocks(s->block[0]);
1048
1049             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1050             if (mb_block_count > 6) {
1051                 cbp <<= mb_block_count - 6;
1052                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
1053                 s->bdsp.clear_blocks(s->block[6]);
1054             }
1055             if (cbp <= 0) {
1056                 av_log(s->avctx, AV_LOG_ERROR,
1057                        "invalid cbp %d at %d %d\n", cbp, s->mb_x, s->mb_y);
1058                 return AVERROR_INVALIDDATA;
1059             }
1060
1061             // if 1, we memcpy blocks in xvmcvideo
1062             if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1063                 ff_xvmc_pack_pblocks(s, cbp);
1064
1065             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1066                 if (s->avctx->flags2 & CODEC_FLAG2_FAST) {
1067                     for (i = 0; i < 6; i++) {
1068                         if (cbp & 32)
1069                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1070                         else
1071                             s->block_last_index[i] = -1;
1072                         cbp += cbp;
1073                     }
1074                 } else {
1075                     cbp <<= 12 - mb_block_count;
1076
1077                     for (i = 0; i < mb_block_count; i++) {
1078                         if (cbp & (1 << 11)) {
1079                             if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
1080                                 return ret;
1081                         } else {
1082                             s->block_last_index[i] = -1;
1083                         }
1084                         cbp += cbp;
1085                     }
1086                 }
1087             } else {
1088                 if (s->avctx->flags2 & CODEC_FLAG2_FAST) {
1089                     for (i = 0; i < 6; i++) {
1090                         if (cbp & 32)
1091                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1092                         else
1093                             s->block_last_index[i] = -1;
1094                         cbp += cbp;
1095                     }
1096                 } else {
1097                     for (i = 0; i < 6; i++) {
1098                         if (cbp & 32) {
1099                             if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
1100                                 return ret;
1101                         } else {
1102                             s->block_last_index[i] = -1;
1103                         }
1104                         cbp += cbp;
1105                     }
1106                 }
1107             }
1108         } else {
1109             for (i = 0; i < 12; i++)
1110                 s->block_last_index[i] = -1;
1111         }
1112     }
1113
1114     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1115
1116     return 0;
1117 }
1118
1119 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1120 {
1121     Mpeg1Context *s    = avctx->priv_data;
1122     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1123
1124     ff_mpv_decode_defaults(s2);
1125
1126     if (   avctx->codec_tag != AV_RL32("VCR2")
1127         && avctx->codec_tag != AV_RL32("BW10"))
1128         avctx->coded_width = avctx->coded_height = 0; // do not trust dimensions from input
1129     ff_mpv_decode_init(s2, avctx);
1130
1131     s->mpeg_enc_ctx.avctx  = avctx;
1132
1133     /* we need some permutation to store matrices,
1134      * until the decoder sets the real permutation. */
1135     ff_mpv_idct_init(s2);
1136     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1137     ff_mpeg12_init_vlcs();
1138
1139     s->mpeg_enc_ctx_allocated      = 0;
1140     s->mpeg_enc_ctx.picture_number = 0;
1141     s->repeat_field                = 0;
1142     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1143     avctx->color_range             = AVCOL_RANGE_MPEG;
1144     return 0;
1145 }
1146
1147 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1148                                              const AVCodecContext *avctx_from)
1149 {
1150     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1151     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1152     int err;
1153
1154     if (avctx == avctx_from               ||
1155         !ctx_from->mpeg_enc_ctx_allocated ||
1156         !s1->context_initialized)
1157         return 0;
1158
1159     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1160     if (err)
1161         return err;
1162
1163     if (!ctx->mpeg_enc_ctx_allocated)
1164         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1165
1166     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1167         s->picture_number++;
1168
1169     return 0;
1170 }
1171
1172 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1173                                  const uint8_t *new_perm)
1174 {
1175     uint16_t temp_matrix[64];
1176     int i;
1177
1178     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1179
1180     for (i = 0; i < 64; i++)
1181         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1182 }
1183
1184 static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1185 #if CONFIG_MPEG1_XVMC_HWACCEL
1186     AV_PIX_FMT_XVMC,
1187 #endif
1188 #if CONFIG_MPEG1_VDPAU_HWACCEL
1189     AV_PIX_FMT_VDPAU_MPEG1,
1190     AV_PIX_FMT_VDPAU,
1191 #endif
1192     AV_PIX_FMT_YUV420P,
1193     AV_PIX_FMT_NONE
1194 };
1195
1196 static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1197 #if CONFIG_MPEG2_XVMC_HWACCEL
1198     AV_PIX_FMT_XVMC,
1199 #endif
1200 #if CONFIG_MPEG2_VDPAU_HWACCEL
1201     AV_PIX_FMT_VDPAU_MPEG2,
1202     AV_PIX_FMT_VDPAU,
1203 #endif
1204 #if CONFIG_MPEG2_DXVA2_HWACCEL
1205     AV_PIX_FMT_DXVA2_VLD,
1206 #endif
1207 #if CONFIG_MPEG2_D3D11VA_HWACCEL
1208     AV_PIX_FMT_D3D11VA_VLD,
1209 #endif
1210 #if CONFIG_MPEG2_VAAPI_HWACCEL
1211     AV_PIX_FMT_VAAPI_VLD,
1212 #endif
1213     AV_PIX_FMT_YUV420P,
1214     AV_PIX_FMT_NONE
1215 };
1216
1217 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1218     AV_PIX_FMT_YUV422P,
1219     AV_PIX_FMT_NONE
1220 };
1221
1222 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1223     AV_PIX_FMT_YUV444P,
1224     AV_PIX_FMT_NONE
1225 };
1226
1227 static inline int uses_vdpau(AVCodecContext *avctx) {
1228     return avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG1 || avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG2;
1229 }
1230
1231 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1232 {
1233     Mpeg1Context *s1  = avctx->priv_data;
1234     MpegEncContext *s = &s1->mpeg_enc_ctx;
1235     const enum AVPixelFormat *pix_fmts;
1236
1237     if (CONFIG_GRAY && (avctx->flags & CODEC_FLAG_GRAY))
1238         return AV_PIX_FMT_GRAY8;
1239
1240     if (s->chroma_format < 2)
1241         pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1242                                 mpeg1_hwaccel_pixfmt_list_420 :
1243                                 mpeg2_hwaccel_pixfmt_list_420;
1244     else if (s->chroma_format == 2)
1245         pix_fmts = mpeg12_pixfmt_list_422;
1246     else
1247         pix_fmts = mpeg12_pixfmt_list_444;
1248
1249     return ff_thread_get_format(avctx, pix_fmts);
1250 }
1251
1252 static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
1253 {
1254     // until then pix_fmt may be changed right after codec init
1255     if (avctx->hwaccel || uses_vdpau(avctx))
1256         if (avctx->idct_algo == FF_IDCT_AUTO)
1257             avctx->idct_algo = FF_IDCT_SIMPLE;
1258
1259     if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
1260         Mpeg1Context *s1 = avctx->priv_data;
1261         MpegEncContext *s = &s1->mpeg_enc_ctx;
1262
1263         s->pack_pblocks = 1;
1264 #if FF_API_XVMC
1265         avctx->xvmc_acceleration = 2;
1266 #endif /* FF_API_XVMC */
1267     }
1268 }
1269
1270 /* Call this function when we know all parameters.
1271  * It may be called in different places for MPEG-1 and MPEG-2. */
1272 static int mpeg_decode_postinit(AVCodecContext *avctx)
1273 {
1274     Mpeg1Context *s1  = avctx->priv_data;
1275     MpegEncContext *s = &s1->mpeg_enc_ctx;
1276     uint8_t old_permutation[64];
1277     int ret;
1278
1279     if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1280         // MPEG-1 aspect
1281         avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1282     } else { // MPEG-2
1283         // MPEG-2 aspect
1284         if (s->aspect_ratio_info > 1) {
1285             AVRational dar =
1286                 av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1287                                   (AVRational) { s1->pan_scan.width,
1288                                                  s1->pan_scan.height }),
1289                          (AVRational) { s->width, s->height });
1290
1291             /* We ignore the spec here and guess a bit as reality does not
1292              * match the spec, see for example res_change_ffmpeg_aspect.ts
1293              * and sequence-display-aspect.mpg.
1294              * issue1613, 621, 562 */
1295             if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1296                 (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1297                  av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1298                 s->avctx->sample_aspect_ratio =
1299                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1300                              (AVRational) { s->width, s->height });
1301             } else {
1302                 s->avctx->sample_aspect_ratio =
1303                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1304                              (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1305 // issue1613 4/3 16/9 -> 16/9
1306 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1307 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1308 //                s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1309                 ff_dlog(avctx, "aspect A %d/%d\n",
1310                         ff_mpeg2_aspect[s->aspect_ratio_info].num,
1311                         ff_mpeg2_aspect[s->aspect_ratio_info].den);
1312                 ff_dlog(avctx, "aspect B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1313                         s->avctx->sample_aspect_ratio.den);
1314             }
1315         } else {
1316             s->avctx->sample_aspect_ratio =
1317                 ff_mpeg2_aspect[s->aspect_ratio_info];
1318         }
1319     } // MPEG-2
1320
1321     if (av_image_check_sar(s->width, s->height,
1322                            avctx->sample_aspect_ratio) < 0) {
1323         av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
1324                 avctx->sample_aspect_ratio.num,
1325                 avctx->sample_aspect_ratio.den);
1326         avctx->sample_aspect_ratio = (AVRational){ 0, 1 };
1327     }
1328
1329     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1330         avctx->coded_width       != s->width                ||
1331         avctx->coded_height      != s->height               ||
1332         s1->save_width           != s->width                ||
1333         s1->save_height          != s->height               ||
1334         av_cmp_q(s1->save_aspect, s->avctx->sample_aspect_ratio) ||
1335         (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1336         0) {
1337         if (s1->mpeg_enc_ctx_allocated) {
1338             ParseContext pc = s->parse_context;
1339             s->parse_context.buffer = 0;
1340             ff_mpv_common_end(s);
1341             s->parse_context = pc;
1342             s1->mpeg_enc_ctx_allocated = 0;
1343         }
1344
1345         ret = ff_set_dimensions(avctx, s->width, s->height);
1346         if (ret < 0)
1347             return ret;
1348
1349         if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
1350             avctx->rc_max_rate = s->bit_rate;
1351         } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
1352                    (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
1353             avctx->bit_rate = s->bit_rate;
1354         }
1355         s1->save_aspect          = s->avctx->sample_aspect_ratio;
1356         s1->save_width           = s->width;
1357         s1->save_height          = s->height;
1358         s1->save_progressive_seq = s->progressive_sequence;
1359
1360         /* low_delay may be forced, in this case we will have B-frames
1361          * that behave like P-frames. */
1362         avctx->has_b_frames = !s->low_delay;
1363
1364         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1365             // MPEG-1 fps
1366             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1367             avctx->ticks_per_frame     = 1;
1368
1369             avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1370         } else { // MPEG-2
1371             // MPEG-2 fps
1372             av_reduce(&s->avctx->framerate.num,
1373                       &s->avctx->framerate.den,
1374                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1375                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1376                       1 << 30);
1377             avctx->ticks_per_frame = 2;
1378
1379             switch (s->chroma_format) {
1380             case 1: avctx->chroma_sample_location = AVCHROMA_LOC_LEFT; break;
1381             case 2:
1382             case 3: avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT; break;
1383             }
1384         } // MPEG-2
1385
1386         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1387         setup_hwaccel_for_pixfmt(avctx);
1388
1389         /* Quantization matrices may need reordering
1390          * if DCT permutation is changed. */
1391         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1392
1393         ff_mpv_idct_init(s);
1394         if ((ret = ff_mpv_common_init(s)) < 0)
1395             return ret;
1396
1397         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1398         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1399         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1400         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1401
1402         s1->mpeg_enc_ctx_allocated = 1;
1403     }
1404     return 0;
1405 }
1406
1407 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1408                                 int buf_size)
1409 {
1410     Mpeg1Context *s1  = avctx->priv_data;
1411     MpegEncContext *s = &s1->mpeg_enc_ctx;
1412     int ref, f_code, vbv_delay;
1413
1414     init_get_bits(&s->gb, buf, buf_size * 8);
1415
1416     ref = get_bits(&s->gb, 10); /* temporal ref */
1417     s->pict_type = get_bits(&s->gb, 3);
1418     if (s->pict_type == 0 || s->pict_type > 3)
1419         return AVERROR_INVALIDDATA;
1420
1421     vbv_delay = get_bits(&s->gb, 16);
1422     s->vbv_delay = vbv_delay;
1423     if (s->pict_type == AV_PICTURE_TYPE_P ||
1424         s->pict_type == AV_PICTURE_TYPE_B) {
1425         s->full_pel[0] = get_bits1(&s->gb);
1426         f_code = get_bits(&s->gb, 3);
1427         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1428             return AVERROR_INVALIDDATA;
1429         f_code += !f_code;
1430         s->mpeg_f_code[0][0] = f_code;
1431         s->mpeg_f_code[0][1] = f_code;
1432     }
1433     if (s->pict_type == AV_PICTURE_TYPE_B) {
1434         s->full_pel[1] = get_bits1(&s->gb);
1435         f_code = get_bits(&s->gb, 3);
1436         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1437             return AVERROR_INVALIDDATA;
1438         f_code += !f_code;
1439         s->mpeg_f_code[1][0] = f_code;
1440         s->mpeg_f_code[1][1] = f_code;
1441     }
1442     s->current_picture.f->pict_type = s->pict_type;
1443     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1444
1445     if (avctx->debug & FF_DEBUG_PICT_INFO)
1446         av_log(avctx, AV_LOG_DEBUG,
1447                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1448
1449     s->y_dc_scale = 8;
1450     s->c_dc_scale = 8;
1451     return 0;
1452 }
1453
1454 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1455 {
1456     MpegEncContext *s = &s1->mpeg_enc_ctx;
1457     int horiz_size_ext, vert_size_ext;
1458     int bit_rate_ext;
1459
1460     skip_bits(&s->gb, 1); /* profile and level esc*/
1461     s->avctx->profile       = get_bits(&s->gb, 3);
1462     s->avctx->level         = get_bits(&s->gb, 4);
1463     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1464     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1465     horiz_size_ext          = get_bits(&s->gb, 2);
1466     vert_size_ext           = get_bits(&s->gb, 2);
1467     s->width  |= (horiz_size_ext << 12);
1468     s->height |= (vert_size_ext  << 12);
1469     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1470     s->bit_rate += (bit_rate_ext << 18) * 400;
1471     check_marker(&s->gb, "after bit rate extension");
1472     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1473
1474     s->low_delay = get_bits1(&s->gb);
1475     if (s->avctx->flags & CODEC_FLAG_LOW_DELAY)
1476         s->low_delay = 1;
1477
1478     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1479     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1480
1481     ff_dlog(s->avctx, "sequence extension\n");
1482     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1483
1484     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1485         av_log(s->avctx, AV_LOG_DEBUG,
1486                "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%d\n",
1487                s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1488                s->avctx->rc_buffer_size, s->bit_rate);
1489 }
1490
1491 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1492 {
1493     MpegEncContext *s = &s1->mpeg_enc_ctx;
1494     int color_description, w, h;
1495
1496     skip_bits(&s->gb, 3); /* video format */
1497     color_description = get_bits1(&s->gb);
1498     if (color_description) {
1499         s->avctx->color_primaries = get_bits(&s->gb, 8);
1500         s->avctx->color_trc       = get_bits(&s->gb, 8);
1501         s->avctx->colorspace      = get_bits(&s->gb, 8);
1502     }
1503     w = get_bits(&s->gb, 14);
1504     skip_bits(&s->gb, 1); // marker
1505     h = get_bits(&s->gb, 14);
1506     // remaining 3 bits are zero padding
1507
1508     s1->pan_scan.width  = 16 * w;
1509     s1->pan_scan.height = 16 * h;
1510
1511     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1512         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1513 }
1514
1515 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1516 {
1517     MpegEncContext *s = &s1->mpeg_enc_ctx;
1518     int i, nofco;
1519
1520     nofco = 1;
1521     if (s->progressive_sequence) {
1522         if (s->repeat_first_field) {
1523             nofco++;
1524             if (s->top_field_first)
1525                 nofco++;
1526         }
1527     } else {
1528         if (s->picture_structure == PICT_FRAME) {
1529             nofco++;
1530             if (s->repeat_first_field)
1531                 nofco++;
1532         }
1533     }
1534     for (i = 0; i < nofco; i++) {
1535         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1536         skip_bits(&s->gb, 1); // marker
1537         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1538         skip_bits(&s->gb, 1); // marker
1539     }
1540
1541     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1542         av_log(s->avctx, AV_LOG_DEBUG,
1543                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1544                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1545                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1546                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1547 }
1548
1549 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1550                        uint16_t matrix1[64], int intra)
1551 {
1552     int i;
1553
1554     for (i = 0; i < 64; i++) {
1555         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1556         int v = get_bits(&s->gb, 8);
1557         if (v == 0) {
1558             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1559             return AVERROR_INVALIDDATA;
1560         }
1561         if (intra && i == 0 && v != 8) {
1562             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1563             v = 8; // needed by pink.mpg / issue1046
1564         }
1565         matrix0[j] = v;
1566         if (matrix1)
1567             matrix1[j] = v;
1568     }
1569     return 0;
1570 }
1571
1572 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1573 {
1574     ff_dlog(s->avctx, "matrix extension\n");
1575
1576     if (get_bits1(&s->gb))
1577         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1578     if (get_bits1(&s->gb))
1579         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1580     if (get_bits1(&s->gb))
1581         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1582     if (get_bits1(&s->gb))
1583         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1584 }
1585
1586 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1587 {
1588     MpegEncContext *s = &s1->mpeg_enc_ctx;
1589
1590     s->full_pel[0]       = s->full_pel[1] = 0;
1591     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1592     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1593     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1594     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1595     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1596         av_log(s->avctx, AV_LOG_ERROR,
1597                "Missing picture start code, guessing missing values\n");
1598         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1599             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1600                 s->pict_type = AV_PICTURE_TYPE_I;
1601             else
1602                 s->pict_type = AV_PICTURE_TYPE_P;
1603         } else
1604             s->pict_type = AV_PICTURE_TYPE_B;
1605         s->current_picture.f->pict_type = s->pict_type;
1606         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1607     }
1608     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1609     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1610     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1611     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1612
1613     s->intra_dc_precision         = get_bits(&s->gb, 2);
1614     s->picture_structure          = get_bits(&s->gb, 2);
1615     s->top_field_first            = get_bits1(&s->gb);
1616     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1617     s->concealment_motion_vectors = get_bits1(&s->gb);
1618     s->q_scale_type               = get_bits1(&s->gb);
1619     s->intra_vlc_format           = get_bits1(&s->gb);
1620     s->alternate_scan             = get_bits1(&s->gb);
1621     s->repeat_first_field         = get_bits1(&s->gb);
1622     s->chroma_420_type            = get_bits1(&s->gb);
1623     s->progressive_frame          = get_bits1(&s->gb);
1624
1625     if (s->alternate_scan) {
1626         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1627         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1628     } else {
1629         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1630         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1631     }
1632
1633     /* composite display not parsed */
1634     ff_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1635     ff_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1636     ff_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1637     ff_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1638     ff_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1639     ff_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1640     ff_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1641     ff_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1642     ff_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1643 }
1644
1645 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1646 {
1647     AVCodecContext *avctx = s->avctx;
1648     Mpeg1Context *s1      = (Mpeg1Context *) s;
1649     int ret;
1650
1651     /* start frame decoding */
1652     if (s->first_field || s->picture_structure == PICT_FRAME) {
1653         AVFrameSideData *pan_scan;
1654
1655         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1656             return ret;
1657
1658         ff_mpeg_er_frame_start(s);
1659
1660         /* first check if we must repeat the frame */
1661         s->current_picture_ptr->f->repeat_pict = 0;
1662         if (s->repeat_first_field) {
1663             if (s->progressive_sequence) {
1664                 if (s->top_field_first)
1665                     s->current_picture_ptr->f->repeat_pict = 4;
1666                 else
1667                     s->current_picture_ptr->f->repeat_pict = 2;
1668             } else if (s->progressive_frame) {
1669                 s->current_picture_ptr->f->repeat_pict = 1;
1670             }
1671         }
1672
1673         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1674                                           AV_FRAME_DATA_PANSCAN,
1675                                           sizeof(s1->pan_scan));
1676         if (!pan_scan)
1677             return AVERROR(ENOMEM);
1678         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1679
1680         if (s1->a53_caption) {
1681             AVFrameSideData *sd = av_frame_new_side_data(
1682                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1683                 s1->a53_caption_size);
1684             if (sd)
1685                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1686             av_freep(&s1->a53_caption);
1687         }
1688
1689         if (s1->has_stereo3d) {
1690             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1691             if (!stereo)
1692                 return AVERROR(ENOMEM);
1693
1694             *stereo = s1->stereo3d;
1695             s1->has_stereo3d = 0;
1696         }
1697
1698         if (s1->has_afd) {
1699             AVFrameSideData *sd =
1700                 av_frame_new_side_data(s->current_picture_ptr->f,
1701                                        AV_FRAME_DATA_AFD, 1);
1702             if (!sd)
1703                 return AVERROR(ENOMEM);
1704
1705             *sd->data   = s1->afd;
1706             s1->has_afd = 0;
1707         }
1708
1709         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1710             ff_thread_finish_setup(avctx);
1711     } else { // second field
1712         int i;
1713
1714         if (!s->current_picture_ptr) {
1715             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1716             return AVERROR_INVALIDDATA;
1717         }
1718
1719         if (s->avctx->hwaccel &&
1720             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1721             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1722                 av_log(avctx, AV_LOG_ERROR,
1723                        "hardware accelerator failed to decode first field\n");
1724         }
1725
1726         for (i = 0; i < 4; i++) {
1727             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1728             if (s->picture_structure == PICT_BOTTOM_FIELD)
1729                 s->current_picture.f->data[i] +=
1730                     s->current_picture_ptr->f->linesize[i];
1731         }
1732     }
1733
1734     if (avctx->hwaccel) {
1735         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1736             return ret;
1737     }
1738
1739     return 0;
1740 }
1741
1742 #define DECODE_SLICE_ERROR -1
1743 #define DECODE_SLICE_OK     0
1744
1745 /**
1746  * Decode a slice.
1747  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1748  * @return DECODE_SLICE_ERROR if the slice is damaged,
1749  *         DECODE_SLICE_OK if this slice is OK
1750  */
1751 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1752                              const uint8_t **buf, int buf_size)
1753 {
1754     AVCodecContext *avctx = s->avctx;
1755     const int lowres      = s->avctx->lowres;
1756     const int field_pic   = s->picture_structure != PICT_FRAME;
1757     int ret;
1758
1759     s->resync_mb_x =
1760     s->resync_mb_y = -1;
1761
1762     av_assert0(mb_y < s->mb_height);
1763
1764     init_get_bits(&s->gb, *buf, buf_size * 8);
1765     if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1766         skip_bits(&s->gb, 3);
1767
1768     ff_mpeg1_clean_buffers(s);
1769     s->interlaced_dct = 0;
1770
1771     s->qscale = get_qscale(s);
1772
1773     if (s->qscale == 0) {
1774         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1775         return AVERROR_INVALIDDATA;
1776     }
1777
1778     /* extra slice info */
1779     if (skip_1stop_8data_bits(&s->gb) < 0)
1780         return AVERROR_INVALIDDATA;
1781
1782     s->mb_x = 0;
1783
1784     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1785         skip_bits1(&s->gb);
1786     } else {
1787         while (get_bits_left(&s->gb) > 0) {
1788             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1789                                 MBINCR_VLC_BITS, 2);
1790             if (code < 0) {
1791                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1792                 return AVERROR_INVALIDDATA;
1793             }
1794             if (code >= 33) {
1795                 if (code == 33)
1796                     s->mb_x += 33;
1797                 /* otherwise, stuffing, nothing to do */
1798             } else {
1799                 s->mb_x += code;
1800                 break;
1801             }
1802         }
1803     }
1804
1805     if (s->mb_x >= (unsigned) s->mb_width) {
1806         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1807         return AVERROR_INVALIDDATA;
1808     }
1809
1810     if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1811         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1812         int start_code = -1;
1813         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1814         if (buf_end < *buf + buf_size)
1815             buf_end -= 4;
1816         s->mb_y = mb_y;
1817         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1818             return DECODE_SLICE_ERROR;
1819         *buf = buf_end;
1820         return DECODE_SLICE_OK;
1821     }
1822
1823     s->resync_mb_x = s->mb_x;
1824     s->resync_mb_y = s->mb_y = mb_y;
1825     s->mb_skip_run = 0;
1826     ff_init_block_index(s);
1827
1828     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1829         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1830             av_log(s->avctx, AV_LOG_DEBUG,
1831                    "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",
1832                    s->qscale,
1833                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1834                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1835                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1836                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1837                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1838                    s->progressive_sequence ? "ps"  : "",
1839                    s->progressive_frame    ? "pf"  : "",
1840                    s->alternate_scan       ? "alt" : "",
1841                    s->top_field_first      ? "top" : "",
1842                    s->intra_dc_precision, s->picture_structure,
1843                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1844                    s->q_scale_type, s->intra_vlc_format,
1845                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1846         }
1847     }
1848
1849     for (;;) {
1850         // If 1, we memcpy blocks in xvmcvideo.
1851         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1852             ff_xvmc_init_block(s); // set s->block
1853
1854         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1855             return ret;
1856
1857         // Note motion_val is normally NULL unless we want to extract the MVs.
1858         if (s->current_picture.motion_val[0] && !s->encoding) {
1859             const int wrap = s->b8_stride;
1860             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1861             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1862             int motion_x, motion_y, dir, i;
1863
1864             for (i = 0; i < 2; i++) {
1865                 for (dir = 0; dir < 2; dir++) {
1866                     if (s->mb_intra ||
1867                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1868                         motion_x = motion_y = 0;
1869                     } else if (s->mv_type == MV_TYPE_16X16 ||
1870                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1871                         motion_x = s->mv[dir][0][0];
1872                         motion_y = s->mv[dir][0][1];
1873                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1874                         motion_x = s->mv[dir][i][0];
1875                         motion_y = s->mv[dir][i][1];
1876                     }
1877
1878                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1879                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1880                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1881                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1882                     s->current_picture.ref_index [dir][b8_xy]     =
1883                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1884                     av_assert2(s->field_select[dir][i] == 0 ||
1885                                s->field_select[dir][i] == 1);
1886                 }
1887                 xy    += wrap;
1888                 b8_xy += 2;
1889             }
1890         }
1891
1892         s->dest[0] += 16 >> lowres;
1893         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1894         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1895
1896         ff_mpv_decode_mb(s, s->block);
1897
1898         if (++s->mb_x >= s->mb_width) {
1899             const int mb_size = 16 >> s->avctx->lowres;
1900
1901             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1902             ff_mpv_report_decode_progress(s);
1903
1904             s->mb_x  = 0;
1905             s->mb_y += 1 << field_pic;
1906
1907             if (s->mb_y >= s->mb_height) {
1908                 int left   = get_bits_left(&s->gb);
1909                 int is_d10 = s->chroma_format == 2 &&
1910                              s->pict_type == AV_PICTURE_TYPE_I &&
1911                              avctx->profile == 0 && avctx->level == 5 &&
1912                              s->intra_dc_precision == 2 &&
1913                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1914                              s->progressive_frame == 0
1915                              /* vbv_delay == 0xBBB || 0xE10 */;
1916
1917                 if (left >= 32 && !is_d10) {
1918                     GetBitContext gb = s->gb;
1919                     align_get_bits(&gb);
1920                     if (show_bits(&gb, 24) == 0x060E2B) {
1921                         av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
1922                         is_d10 = 1;
1923                     }
1924                 }
1925
1926                 if (left < 0 ||
1927                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1928                     ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1929                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1930                            left, show_bits(&s->gb, FFMIN(left, 23)));
1931                     return AVERROR_INVALIDDATA;
1932                 } else
1933                     goto eos;
1934             }
1935             // There are some files out there which are missing the last slice
1936             // in cases where the slice is completely outside the visible
1937             // area, we detect this here instead of running into the end expecting
1938             // more data
1939             if (s->mb_y >= ((s->height + 15) >> 4) &&
1940                 s->progressive_frame &&
1941                 !s->progressive_sequence &&
1942                 get_bits_left(&s->gb) <= 8 &&
1943                 get_bits_left(&s->gb) >= 0 &&
1944                 s->mb_skip_run == -1 &&
1945                 show_bits(&s->gb, 8) == 0)
1946                 goto eos;
1947
1948             ff_init_block_index(s);
1949         }
1950
1951         /* skip mb handling */
1952         if (s->mb_skip_run == -1) {
1953             /* read increment again */
1954             s->mb_skip_run = 0;
1955             for (;;) {
1956                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1957                                     MBINCR_VLC_BITS, 2);
1958                 if (code < 0) {
1959                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1960                     return AVERROR_INVALIDDATA;
1961                 }
1962                 if (code >= 33) {
1963                     if (code == 33) {
1964                         s->mb_skip_run += 33;
1965                     } else if (code == 35) {
1966                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1967                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1968                             return AVERROR_INVALIDDATA;
1969                         }
1970                         goto eos; /* end of slice */
1971                     }
1972                     /* otherwise, stuffing, nothing to do */
1973                 } else {
1974                     s->mb_skip_run += code;
1975                     break;
1976                 }
1977             }
1978             if (s->mb_skip_run) {
1979                 int i;
1980                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1981                     av_log(s->avctx, AV_LOG_ERROR,
1982                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1983                     return AVERROR_INVALIDDATA;
1984                 }
1985
1986                 /* skip mb */
1987                 s->mb_intra = 0;
1988                 for (i = 0; i < 12; i++)
1989                     s->block_last_index[i] = -1;
1990                 if (s->picture_structure == PICT_FRAME)
1991                     s->mv_type = MV_TYPE_16X16;
1992                 else
1993                     s->mv_type = MV_TYPE_FIELD;
1994                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1995                     /* if P type, zero motion vector is implied */
1996                     s->mv_dir             = MV_DIR_FORWARD;
1997                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1998                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1999                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
2000                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
2001                 } else {
2002                     /* if B type, reuse previous vectors and directions */
2003                     s->mv[0][0][0] = s->last_mv[0][0][0];
2004                     s->mv[0][0][1] = s->last_mv[0][0][1];
2005                     s->mv[1][0][0] = s->last_mv[1][0][0];
2006                     s->mv[1][0][1] = s->last_mv[1][0][1];
2007                 }
2008             }
2009         }
2010     }
2011 eos: // end of slice
2012     if (get_bits_left(&s->gb) < 0) {
2013         av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
2014         return AVERROR_INVALIDDATA;
2015     }
2016     *buf += (get_bits_count(&s->gb) - 1) / 8;
2017     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);
2018     return 0;
2019 }
2020
2021 static int slice_decode_thread(AVCodecContext *c, void *arg)
2022 {
2023     MpegEncContext *s   = *(void **) arg;
2024     const uint8_t *buf  = s->gb.buffer;
2025     int mb_y            = s->start_mb_y;
2026     const int field_pic = s->picture_structure != PICT_FRAME;
2027
2028     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
2029
2030     for (;;) {
2031         uint32_t start_code;
2032         int ret;
2033
2034         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
2035         emms_c();
2036         ff_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2037                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
2038                 s->start_mb_y, s->end_mb_y, s->er.error_count);
2039         if (ret < 0) {
2040             if (c->err_recognition & AV_EF_EXPLODE)
2041                 return ret;
2042             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
2043                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2044                                 s->mb_x, s->mb_y,
2045                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2046         } else {
2047             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2048                             s->mb_x - 1, s->mb_y,
2049                             ER_AC_END | ER_DC_END | ER_MV_END);
2050         }
2051
2052         if (s->mb_y == s->end_mb_y)
2053             return 0;
2054
2055         start_code = -1;
2056         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2057         mb_y       = start_code - SLICE_MIN_START_CODE;
2058         if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2059             mb_y += (*buf&0xE0)<<2;
2060         mb_y <<= field_pic;
2061         if (s->picture_structure == PICT_BOTTOM_FIELD)
2062             mb_y++;
2063         if (mb_y < 0 || mb_y >= s->end_mb_y)
2064             return AVERROR_INVALIDDATA;
2065     }
2066 }
2067
2068 /**
2069  * Handle slice ends.
2070  * @return 1 if it seems to be the last slice
2071  */
2072 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2073 {
2074     Mpeg1Context *s1  = avctx->priv_data;
2075     MpegEncContext *s = &s1->mpeg_enc_ctx;
2076
2077     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2078         return 0;
2079
2080     if (s->avctx->hwaccel) {
2081         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
2082             av_log(avctx, AV_LOG_ERROR,
2083                    "hardware accelerator failed to decode picture\n");
2084     }
2085
2086     /* end of slice reached */
2087     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
2088         /* end of image */
2089
2090         ff_er_frame_end(&s->er);
2091
2092         ff_mpv_frame_end(s);
2093
2094         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2095             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2096             if (ret < 0)
2097                 return ret;
2098             ff_print_debug_info(s, s->current_picture_ptr, pict);
2099             ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2100         } else {
2101             if (avctx->active_thread_type & FF_THREAD_FRAME)
2102                 s->picture_number++;
2103             /* latency of 1 frame for I- and P-frames */
2104             /* XXX: use another variable than picture_number */
2105             if (s->last_picture_ptr) {
2106                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2107                 if (ret < 0)
2108                     return ret;
2109                 ff_print_debug_info(s, s->last_picture_ptr, pict);
2110                 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2111             }
2112         }
2113
2114         return 1;
2115     } else {
2116         return 0;
2117     }
2118 }
2119
2120 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2121                                  const uint8_t *buf, int buf_size)
2122 {
2123     Mpeg1Context *s1  = avctx->priv_data;
2124     MpegEncContext *s = &s1->mpeg_enc_ctx;
2125     int width, height;
2126     int i, v, j;
2127
2128     init_get_bits(&s->gb, buf, buf_size * 8);
2129
2130     width  = get_bits(&s->gb, 12);
2131     height = get_bits(&s->gb, 12);
2132     if (width == 0 || height == 0) {
2133         av_log(avctx, AV_LOG_WARNING,
2134                "Invalid horizontal or vertical size value.\n");
2135         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2136             return AVERROR_INVALIDDATA;
2137     }
2138     s->aspect_ratio_info = get_bits(&s->gb, 4);
2139     if (s->aspect_ratio_info == 0) {
2140         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2141         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2142             return AVERROR_INVALIDDATA;
2143     }
2144     s->frame_rate_index = get_bits(&s->gb, 4);
2145     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2146         av_log(avctx, AV_LOG_WARNING,
2147                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2148         s->frame_rate_index = 1;
2149     }
2150     s->bit_rate = get_bits(&s->gb, 18) * 400;
2151     if (check_marker(&s->gb, "in sequence header") == 0) {
2152         return AVERROR_INVALIDDATA;
2153     }
2154     s->width  = width;
2155     s->height = height;
2156
2157     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2158     skip_bits(&s->gb, 1);
2159
2160     /* get matrix */
2161     if (get_bits1(&s->gb)) {
2162         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2163     } else {
2164         for (i = 0; i < 64; i++) {
2165             j = s->idsp.idct_permutation[i];
2166             v = ff_mpeg1_default_intra_matrix[i];
2167             s->intra_matrix[j]        = v;
2168             s->chroma_intra_matrix[j] = v;
2169         }
2170     }
2171     if (get_bits1(&s->gb)) {
2172         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2173     } else {
2174         for (i = 0; i < 64; i++) {
2175             int j = s->idsp.idct_permutation[i];
2176             v = ff_mpeg1_default_non_intra_matrix[i];
2177             s->inter_matrix[j]        = v;
2178             s->chroma_inter_matrix[j] = v;
2179         }
2180     }
2181
2182     if (show_bits(&s->gb, 23) != 0) {
2183         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2184         return AVERROR_INVALIDDATA;
2185     }
2186
2187     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2188     s->progressive_sequence = 1;
2189     s->progressive_frame    = 1;
2190     s->picture_structure    = PICT_FRAME;
2191     s->first_field          = 0;
2192     s->frame_pred_frame_dct = 1;
2193     s->chroma_format        = 1;
2194     s->codec_id             =
2195     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2196     s->out_format           = FMT_MPEG1;
2197     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2198     if (s->avctx->flags & CODEC_FLAG_LOW_DELAY)
2199         s->low_delay = 1;
2200
2201     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2202         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d, aspect_ratio_info: %d \n",
2203                s->avctx->rc_buffer_size, s->bit_rate, s->aspect_ratio_info);
2204
2205     return 0;
2206 }
2207
2208 static int vcr2_init_sequence(AVCodecContext *avctx)
2209 {
2210     Mpeg1Context *s1  = avctx->priv_data;
2211     MpegEncContext *s = &s1->mpeg_enc_ctx;
2212     int i, v, ret;
2213
2214     /* start new MPEG-1 context decoding */
2215     s->out_format = FMT_MPEG1;
2216     if (s1->mpeg_enc_ctx_allocated) {
2217         ff_mpv_common_end(s);
2218         s1->mpeg_enc_ctx_allocated = 0;
2219     }
2220     s->width            = avctx->coded_width;
2221     s->height           = avctx->coded_height;
2222     avctx->has_b_frames = 0; // true?
2223     s->low_delay        = 1;
2224
2225     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2226     setup_hwaccel_for_pixfmt(avctx);
2227
2228     ff_mpv_idct_init(s);
2229     if ((ret = ff_mpv_common_init(s)) < 0)
2230         return ret;
2231     s1->mpeg_enc_ctx_allocated = 1;
2232
2233     for (i = 0; i < 64; i++) {
2234         int j = s->idsp.idct_permutation[i];
2235         v = ff_mpeg1_default_intra_matrix[i];
2236         s->intra_matrix[j]        = v;
2237         s->chroma_intra_matrix[j] = v;
2238
2239         v = ff_mpeg1_default_non_intra_matrix[i];
2240         s->inter_matrix[j]        = v;
2241         s->chroma_inter_matrix[j] = v;
2242     }
2243
2244     s->progressive_sequence  = 1;
2245     s->progressive_frame     = 1;
2246     s->picture_structure     = PICT_FRAME;
2247     s->first_field           = 0;
2248     s->frame_pred_frame_dct  = 1;
2249     s->chroma_format         = 1;
2250     if (s->codec_tag == AV_RL32("BW10")) {
2251         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2252     } else {
2253         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2254         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2255     }
2256     s1->save_width           = s->width;
2257     s1->save_height          = s->height;
2258     s1->save_progressive_seq = s->progressive_sequence;
2259     return 0;
2260 }
2261
2262 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2263                               const uint8_t *p, int buf_size)
2264 {
2265     Mpeg1Context *s1 = avctx->priv_data;
2266
2267     if (buf_size >= 6 &&
2268         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2269         p[4] == 3 && (p[5] & 0x40)) {
2270         /* extract A53 Part 4 CC data */
2271         int cc_count = p[5] & 0x1f;
2272         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2273             av_freep(&s1->a53_caption);
2274             s1->a53_caption_size = cc_count * 3;
2275             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2276             if (s1->a53_caption)
2277                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2278         }
2279         return 1;
2280     } else if (buf_size >= 11 &&
2281                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2282         /* extract DVD CC data */
2283         int cc_count = 0;
2284         int i;
2285         // There is a caption count field in the data, but it is often
2286         // incorect.  So count the number of captions present.
2287         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2288             cc_count++;
2289         // Transform the DVD format into A53 Part 4 format
2290         if (cc_count > 0) {
2291             av_freep(&s1->a53_caption);
2292             s1->a53_caption_size = cc_count * 6;
2293             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2294             if (s1->a53_caption) {
2295                 uint8_t field1 = !!(p[4] & 0x80);
2296                 uint8_t *cap = s1->a53_caption;
2297                 p += 5;
2298                 for (i = 0; i < cc_count; i++) {
2299                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2300                     cap[1] = p[1];
2301                     cap[2] = p[2];
2302                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2303                     cap[4] = p[4];
2304                     cap[5] = p[5];
2305                     cap += 6;
2306                     p += 6;
2307                 }
2308             }
2309         }
2310         return 1;
2311     }
2312     return 0;
2313 }
2314
2315 static void mpeg_decode_user_data(AVCodecContext *avctx,
2316                                   const uint8_t *p, int buf_size)
2317 {
2318     Mpeg1Context *s = avctx->priv_data;
2319     const uint8_t *buf_end = p + buf_size;
2320     Mpeg1Context *s1 = avctx->priv_data;
2321
2322 #if 0
2323     int i;
2324     for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2325         av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
2326     }
2327     av_log(avctx, AV_LOG_ERROR, "\n");
2328 #endif
2329
2330     if (buf_size > 29){
2331         int i;
2332         for(i=0; i<20; i++)
2333             if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2334                 s->tmpgexs= 1;
2335             }
2336     }
2337     /* we parse the DTG active format information */
2338     if (buf_end - p >= 5 &&
2339         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2340         int flags = p[4];
2341         p += 5;
2342         if (flags & 0x80) {
2343             /* skip event id */
2344             p += 2;
2345         }
2346         if (flags & 0x40) {
2347             if (buf_end - p < 1)
2348                 return;
2349 #if FF_API_AFD
2350 FF_DISABLE_DEPRECATION_WARNINGS
2351             avctx->dtg_active_format = p[0] & 0x0f;
2352 FF_ENABLE_DEPRECATION_WARNINGS
2353 #endif /* FF_API_AFD */
2354             s1->has_afd = 1;
2355             s1->afd     = p[0] & 0x0f;
2356         }
2357     } else if (buf_end - p >= 6 &&
2358                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2359                p[4] == 0x03) { // S3D_video_format_length
2360         // the 0x7F mask ignores the reserved_bit value
2361         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2362
2363         if (S3D_video_format_type == 0x03 ||
2364             S3D_video_format_type == 0x04 ||
2365             S3D_video_format_type == 0x08 ||
2366             S3D_video_format_type == 0x23) {
2367
2368             s1->has_stereo3d = 1;
2369
2370             switch (S3D_video_format_type) {
2371             case 0x03:
2372                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2373                 break;
2374             case 0x04:
2375                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2376                 break;
2377             case 0x08:
2378                 s1->stereo3d.type = AV_STEREO3D_2D;
2379                 break;
2380             case 0x23:
2381                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2382                 break;
2383             }
2384         }
2385     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2386         return;
2387     }
2388 }
2389
2390 static void mpeg_decode_gop(AVCodecContext *avctx,
2391                             const uint8_t *buf, int buf_size)
2392 {
2393     Mpeg1Context *s1  = avctx->priv_data;
2394     MpegEncContext *s = &s1->mpeg_enc_ctx;
2395     int broken_link;
2396     int64_t tc;
2397
2398     init_get_bits(&s->gb, buf, buf_size * 8);
2399
2400     tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2401
2402     s->closed_gop = get_bits1(&s->gb);
2403     /* broken_link indicate that after editing the
2404      * reference frames of the first B-Frames after GOP I-Frame
2405      * are missing (open gop) */
2406     broken_link = get_bits1(&s->gb);
2407
2408     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2409         char tcbuf[AV_TIMECODE_STR_SIZE];
2410         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2411         av_log(s->avctx, AV_LOG_DEBUG,
2412                "GOP (%s) closed_gop=%d broken_link=%d\n",
2413                tcbuf, s->closed_gop, broken_link);
2414     }
2415 }
2416
2417 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2418                          int *got_output, const uint8_t *buf, int buf_size)
2419 {
2420     Mpeg1Context *s = avctx->priv_data;
2421     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2422     const uint8_t *buf_ptr = buf;
2423     const uint8_t *buf_end = buf + buf_size;
2424     int ret, input_size;
2425     int last_code = 0, skip_frame = 0;
2426     int picture_start_code_seen = 0;
2427
2428     for (;;) {
2429         /* find next start code */
2430         uint32_t start_code = -1;
2431         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2432         if (start_code > 0x1ff) {
2433             if (!skip_frame) {
2434                 if (HAVE_THREADS &&
2435                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2436                     !avctx->hwaccel) {
2437                     int i;
2438                     av_assert0(avctx->thread_count > 1);
2439
2440                     avctx->execute(avctx, slice_decode_thread,
2441                                    &s2->thread_context[0], NULL,
2442                                    s->slice_count, sizeof(void *));
2443                     for (i = 0; i < s->slice_count; i++)
2444                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2445                 }
2446
2447                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2448                     && uses_vdpau(avctx))
2449                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2450
2451                 ret = slice_end(avctx, picture);
2452                 if (ret < 0)
2453                     return ret;
2454                 else if (ret) {
2455                     // FIXME: merge with the stuff in mpeg_decode_slice
2456                     if (s2->last_picture_ptr || s2->low_delay)
2457                         *got_output = 1;
2458                 }
2459             }
2460             s2->pict_type = 0;
2461
2462             if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
2463                 return AVERROR_INVALIDDATA;
2464
2465             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2466         }
2467
2468         input_size = buf_end - buf_ptr;
2469
2470         if (avctx->debug & FF_DEBUG_STARTCODE)
2471             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2472                    start_code, buf_ptr - buf, input_size);
2473
2474         /* prepare data for next start code */
2475         switch (start_code) {
2476         case SEQ_START_CODE:
2477             if (last_code == 0) {
2478                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2479                 if (buf != avctx->extradata)
2480                     s->sync = 1;
2481             } else {
2482                 av_log(avctx, AV_LOG_ERROR,
2483                        "ignoring SEQ_START_CODE after %X\n", last_code);
2484                 if (avctx->err_recognition & AV_EF_EXPLODE)
2485                     return AVERROR_INVALIDDATA;
2486             }
2487             break;
2488
2489         case PICTURE_START_CODE:
2490             if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
2491                /* If it's a frame picture, there can't be more than one picture header.
2492                   Yet, it does happen and we need to handle it. */
2493                av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
2494                break;
2495             }
2496             picture_start_code_seen = 1;
2497
2498             if (s2->width <= 0 || s2->height <= 0) {
2499                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2500                        s2->width, s2->height);
2501                 return AVERROR_INVALIDDATA;
2502             }
2503
2504             if (s->tmpgexs){
2505                 s2->intra_dc_precision= 3;
2506                 s2->intra_matrix[0]= 1;
2507             }
2508             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2509                 !avctx->hwaccel && s->slice_count) {
2510                 int i;
2511
2512                 avctx->execute(avctx, slice_decode_thread,
2513                                s2->thread_context, NULL,
2514                                s->slice_count, sizeof(void *));
2515                 for (i = 0; i < s->slice_count; i++)
2516                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2517                 s->slice_count = 0;
2518             }
2519             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2520                 ret = mpeg_decode_postinit(avctx);
2521                 if (ret < 0) {
2522                     av_log(avctx, AV_LOG_ERROR,
2523                            "mpeg_decode_postinit() failure\n");
2524                     return ret;
2525                 }
2526
2527                 /* We have a complete image: we try to decompress it. */
2528                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2529                     s2->pict_type = 0;
2530                 s->first_slice = 1;
2531                 last_code      = PICTURE_START_CODE;
2532             } else {
2533                 av_log(avctx, AV_LOG_ERROR,
2534                        "ignoring pic after %X\n", last_code);
2535                 if (avctx->err_recognition & AV_EF_EXPLODE)
2536                     return AVERROR_INVALIDDATA;
2537             }
2538             break;
2539         case EXT_START_CODE:
2540             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2541
2542             switch (get_bits(&s2->gb, 4)) {
2543             case 0x1:
2544                 if (last_code == 0) {
2545                     mpeg_decode_sequence_extension(s);
2546                 } else {
2547                     av_log(avctx, AV_LOG_ERROR,
2548                            "ignoring seq ext after %X\n", last_code);
2549                     if (avctx->err_recognition & AV_EF_EXPLODE)
2550                         return AVERROR_INVALIDDATA;
2551                 }
2552                 break;
2553             case 0x2:
2554                 mpeg_decode_sequence_display_extension(s);
2555                 break;
2556             case 0x3:
2557                 mpeg_decode_quant_matrix_extension(s2);
2558                 break;
2559             case 0x7:
2560                 mpeg_decode_picture_display_extension(s);
2561                 break;
2562             case 0x8:
2563                 if (last_code == PICTURE_START_CODE) {
2564                     mpeg_decode_picture_coding_extension(s);
2565                 } else {
2566                     av_log(avctx, AV_LOG_ERROR,
2567                            "ignoring pic cod ext after %X\n", last_code);
2568                     if (avctx->err_recognition & AV_EF_EXPLODE)
2569                         return AVERROR_INVALIDDATA;
2570                 }
2571                 break;
2572             }
2573             break;
2574         case USER_START_CODE:
2575             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2576             break;
2577         case GOP_START_CODE:
2578             if (last_code == 0) {
2579                 s2->first_field = 0;
2580                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2581                 s->sync = 1;
2582             } else {
2583                 av_log(avctx, AV_LOG_ERROR,
2584                        "ignoring GOP_START_CODE after %X\n", last_code);
2585                 if (avctx->err_recognition & AV_EF_EXPLODE)
2586                     return AVERROR_INVALIDDATA;
2587             }
2588             break;
2589         default:
2590             if (start_code >= SLICE_MIN_START_CODE &&
2591                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2592                 if (s2->progressive_sequence && !s2->progressive_frame) {
2593                     s2->progressive_frame = 1;
2594                     av_log(s2->avctx, AV_LOG_ERROR,
2595                            "interlaced frame in progressive sequence, ignoring\n");
2596                 }
2597
2598                 if (s2->picture_structure == 0 ||
2599                     (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2600                     av_log(s2->avctx, AV_LOG_ERROR,
2601                            "picture_structure %d invalid, ignoring\n",
2602                            s2->picture_structure);
2603                     s2->picture_structure = PICT_FRAME;
2604                 }
2605
2606                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2607                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2608
2609                 if (s2->picture_structure == PICT_FRAME) {
2610                     s2->first_field = 0;
2611                     s2->v_edge_pos  = 16 * s2->mb_height;
2612                 } else {
2613                     s2->first_field ^= 1;
2614                     s2->v_edge_pos   = 8 * s2->mb_height;
2615                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2616                 }
2617             }
2618             if (start_code >= SLICE_MIN_START_CODE &&
2619                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2620                 const int field_pic = s2->picture_structure != PICT_FRAME;
2621                 int mb_y = start_code - SLICE_MIN_START_CODE;
2622                 last_code = SLICE_MIN_START_CODE;
2623                 if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2624                     mb_y += (*buf_ptr&0xE0)<<2;
2625
2626                 mb_y <<= field_pic;
2627                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2628                     mb_y++;
2629
2630                 if (buf_end - buf_ptr < 2) {
2631                     av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
2632                     return AVERROR_INVALIDDATA;
2633                 }
2634
2635                 if (mb_y >= s2->mb_height) {
2636                     av_log(s2->avctx, AV_LOG_ERROR,
2637                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2638                     return AVERROR_INVALIDDATA;
2639                 }
2640
2641                 if (!s2->last_picture_ptr) {
2642                     /* Skip B-frames if we do not have reference frames and
2643                      * GOP is not closed. */
2644                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2645                         if (!s2->closed_gop) {
2646                             skip_frame = 1;
2647                             break;
2648                         }
2649                     }
2650                 }
2651                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->avctx->flags2 & CODEC_FLAG2_SHOW_ALL))
2652                     s->sync = 1;
2653                 if (!s2->next_picture_ptr) {
2654                     /* Skip P-frames if we do not have a reference frame or
2655                      * we have an invalid header. */
2656                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2657                         skip_frame = 1;
2658                         break;
2659                     }
2660                 }
2661                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2662                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2663                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2664                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2665                     avctx->skip_frame >= AVDISCARD_ALL) {
2666                     skip_frame = 1;
2667                     break;
2668                 }
2669
2670                 if (!s->mpeg_enc_ctx_allocated)
2671                     break;
2672
2673                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2674                     if (mb_y < avctx->skip_top ||
2675                         mb_y >= s2->mb_height - avctx->skip_bottom)
2676                         break;
2677                 }
2678
2679                 if (!s2->pict_type) {
2680                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2681                     if (avctx->err_recognition & AV_EF_EXPLODE)
2682                         return AVERROR_INVALIDDATA;
2683                     break;
2684                 }
2685
2686                 if (s->first_slice) {
2687                     skip_frame     = 0;
2688                     s->first_slice = 0;
2689                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2690                         return ret;
2691                 }
2692                 if (!s2->current_picture_ptr) {
2693                     av_log(avctx, AV_LOG_ERROR,
2694                            "current_picture not initialized\n");
2695                     return AVERROR_INVALIDDATA;
2696                 }
2697
2698                 if (uses_vdpau(avctx)) {
2699                     s->slice_count++;
2700                     break;
2701                 }
2702
2703                 if (HAVE_THREADS &&
2704                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2705                     !avctx->hwaccel) {
2706                     int threshold = (s2->mb_height * s->slice_count +
2707                                      s2->slice_context_count / 2) /
2708                                     s2->slice_context_count;
2709                     av_assert0(avctx->thread_count > 1);
2710                     if (threshold <= mb_y) {
2711                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2712
2713                         thread_context->start_mb_y = mb_y;
2714                         thread_context->end_mb_y   = s2->mb_height;
2715                         if (s->slice_count) {
2716                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2717                             ret = ff_update_duplicate_context(thread_context, s2);
2718                             if (ret < 0)
2719                                 return ret;
2720                         }
2721                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2722                         s->slice_count++;
2723                     }
2724                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2725                 } else {
2726                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2727                     emms_c();
2728
2729                     if (ret < 0) {
2730                         if (avctx->err_recognition & AV_EF_EXPLODE)
2731                             return ret;
2732                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2733                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2734                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2735                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2736                     } else {
2737                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2738                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2739                                         ER_AC_END | ER_DC_END | ER_MV_END);
2740                     }
2741                 }
2742             }
2743             break;
2744         }
2745     }
2746 }
2747
2748 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2749                              int *got_output, AVPacket *avpkt)
2750 {
2751     const uint8_t *buf = avpkt->data;
2752     int ret;
2753     int buf_size = avpkt->size;
2754     Mpeg1Context *s = avctx->priv_data;
2755     AVFrame *picture = data;
2756     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2757
2758     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2759         /* special case for last picture */
2760         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2761             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2762             if (ret < 0)
2763                 return ret;
2764
2765             s2->next_picture_ptr = NULL;
2766
2767             *got_output = 1;
2768         }
2769         return buf_size;
2770     }
2771
2772     if (s2->avctx->flags & CODEC_FLAG_TRUNCATED) {
2773         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2774                                            buf_size, NULL);
2775
2776         if (ff_combine_frame(&s2->parse_context, next,
2777                              (const uint8_t **) &buf, &buf_size) < 0)
2778             return buf_size;
2779     }
2780
2781     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2782     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2783                                            || s2->codec_tag == AV_RL32("BW10")
2784                                           ))
2785         vcr2_init_sequence(avctx);
2786
2787     s->slice_count = 0;
2788
2789     if (avctx->extradata && !s->extradata_decoded) {
2790         ret = decode_chunks(avctx, picture, got_output,
2791                             avctx->extradata, avctx->extradata_size);
2792         if (*got_output) {
2793             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2794             *got_output = 0;
2795         }
2796         s->extradata_decoded = 1;
2797         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
2798             s2->current_picture_ptr = NULL;
2799             return ret;
2800         }
2801     }
2802
2803     ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
2804     if (ret<0 || *got_output)
2805         s2->current_picture_ptr = NULL;
2806
2807     return ret;
2808 }
2809
2810 static void flush(AVCodecContext *avctx)
2811 {
2812     Mpeg1Context *s = avctx->priv_data;
2813
2814     s->sync       = 0;
2815
2816     ff_mpeg_flush(avctx);
2817 }
2818
2819 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2820 {
2821     Mpeg1Context *s = avctx->priv_data;
2822
2823     if (s->mpeg_enc_ctx_allocated)
2824         ff_mpv_common_end(&s->mpeg_enc_ctx);
2825     av_freep(&s->a53_caption);
2826     return 0;
2827 }
2828
2829 static const AVProfile mpeg2_video_profiles[] = {
2830     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2831     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2832     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2833     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2834     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2835     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2836     { FF_PROFILE_RESERVED,           "Reserved"           },
2837     { FF_PROFILE_RESERVED,           "Reserved"           },
2838     { FF_PROFILE_UNKNOWN                                  },
2839 };
2840
2841 AVCodec ff_mpeg1video_decoder = {
2842     .name                  = "mpeg1video",
2843     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2844     .type                  = AVMEDIA_TYPE_VIDEO,
2845     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2846     .priv_data_size        = sizeof(Mpeg1Context),
2847     .init                  = mpeg_decode_init,
2848     .close                 = mpeg_decode_end,
2849     .decode                = mpeg_decode_frame,
2850     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2851                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2852                              CODEC_CAP_SLICE_THREADS,
2853     .flush                 = flush,
2854     .max_lowres            = 3,
2855     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2856 };
2857
2858 AVCodec ff_mpeg2video_decoder = {
2859     .name           = "mpeg2video",
2860     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2861     .type           = AVMEDIA_TYPE_VIDEO,
2862     .id             = AV_CODEC_ID_MPEG2VIDEO,
2863     .priv_data_size = sizeof(Mpeg1Context),
2864     .init           = mpeg_decode_init,
2865     .close          = mpeg_decode_end,
2866     .decode         = mpeg_decode_frame,
2867     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2868                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2869                       CODEC_CAP_SLICE_THREADS,
2870     .flush          = flush,
2871     .max_lowres     = 3,
2872     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2873 };
2874
2875 //legacy decoder
2876 AVCodec ff_mpegvideo_decoder = {
2877     .name           = "mpegvideo",
2878     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2879     .type           = AVMEDIA_TYPE_VIDEO,
2880     .id             = AV_CODEC_ID_MPEG2VIDEO,
2881     .priv_data_size = sizeof(Mpeg1Context),
2882     .init           = mpeg_decode_init,
2883     .close          = mpeg_decode_end,
2884     .decode         = mpeg_decode_frame,
2885     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
2886     .flush          = flush,
2887     .max_lowres     = 3,
2888 };
2889
2890 #if FF_API_XVMC
2891 #if CONFIG_MPEG_XVMC_DECODER
2892 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2893 {
2894     if (avctx->active_thread_type & FF_THREAD_SLICE)
2895         return -1;
2896     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2897         return -1;
2898     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2899         ff_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2900     }
2901     mpeg_decode_init(avctx);
2902
2903     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2904     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2905
2906     return 0;
2907 }
2908
2909 AVCodec ff_mpeg_xvmc_decoder = {
2910     .name           = "mpegvideo_xvmc",
2911     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2912     .type           = AVMEDIA_TYPE_VIDEO,
2913     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2914     .priv_data_size = sizeof(Mpeg1Context),
2915     .init           = mpeg_mc_decode_init,
2916     .close          = mpeg_decode_end,
2917     .decode         = mpeg_decode_frame,
2918     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2919                       CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2920     .flush          = flush,
2921 };
2922
2923 #endif
2924 #endif /* FF_API_XVMC */
2925
2926 #if CONFIG_MPEG_VDPAU_DECODER
2927 AVCodec ff_mpeg_vdpau_decoder = {
2928     .name           = "mpegvideo_vdpau",
2929     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2930     .type           = AVMEDIA_TYPE_VIDEO,
2931     .id             = AV_CODEC_ID_MPEG2VIDEO,
2932     .priv_data_size = sizeof(Mpeg1Context),
2933     .init           = mpeg_decode_init,
2934     .close          = mpeg_decode_end,
2935     .decode         = mpeg_decode_frame,
2936     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2937                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2938     .flush          = flush,
2939 };
2940 #endif
2941
2942 #if CONFIG_MPEG1_VDPAU_DECODER
2943 AVCodec ff_mpeg1_vdpau_decoder = {
2944     .name           = "mpeg1video_vdpau",
2945     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2946     .type           = AVMEDIA_TYPE_VIDEO,
2947     .id             = AV_CODEC_ID_MPEG1VIDEO,
2948     .priv_data_size = sizeof(Mpeg1Context),
2949     .init           = mpeg_decode_init,
2950     .close          = mpeg_decode_end,
2951     .decode         = mpeg_decode_frame,
2952     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2953                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2954     .flush          = flush,
2955 };
2956 #endif