git.sesse.net Git - ffmpeg/blob - libavcodec/mpeg12dec.c

   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/internal.h"
  33 #include "libavutil/stereo3d.h"
  34
  35 #include "avcodec.h"
  36 #include "bytestream.h"
  37 #include "error_resilience.h"
  38 #include "idctdsp.h"
  39 #include "internal.h"
  40 #include "mpeg_er.h"
  41 #include "mpeg12.h"
  42 #include "mpeg12data.h"
  43 #include "mpegutils.h"
  44 #include "mpegvideo.h"
  45 #include "thread.h"
  46 #include "version.h"
  47 #include "vdpau_internal.h"
  48 #include "xvmc_internal.h"
  49
  50 typedef struct Mpeg1Context {
  51     MpegEncContext mpeg_enc_ctx;
  52     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  53     int repeat_field;           /* true if we must repeat the field */
  54     AVPanScan pan_scan;         /* some temporary storage for the panscan */
  55     AVStereo3D stereo3d;
  56     int has_stereo3d;
  57     uint8_t *a53_caption;
  58     int a53_caption_size;
  59     uint8_t afd;
  60     int has_afd;
  61     int slice_count;
  62     AVRational save_aspect;
  63     int save_width, save_height, save_progressive_seq;
  64     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
  65     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
  66     int tmpgexs;
  67     int first_slice;
  68     int extradata_decoded;
  69 } Mpeg1Context;
  70
  71 #define MB_TYPE_ZERO_MV   0x20000000
  72
  73 static const uint32_t ptype2mb_type[7] = {
  74                     MB_TYPE_INTRA,
  75                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  76                     MB_TYPE_L0,
  77                     MB_TYPE_L0 | MB_TYPE_CBP,
  78     MB_TYPE_QUANT | MB_TYPE_INTRA,
  79     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
  80     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
  81 };
  82
  83 static const uint32_t btype2mb_type[11] = {
  84                     MB_TYPE_INTRA,
  85                     MB_TYPE_L1,
  86                     MB_TYPE_L1   | MB_TYPE_CBP,
  87                     MB_TYPE_L0,
  88                     MB_TYPE_L0   | MB_TYPE_CBP,
  89                     MB_TYPE_L0L1,
  90                     MB_TYPE_L0L1 | MB_TYPE_CBP,
  91     MB_TYPE_QUANT | MB_TYPE_INTRA,
  92     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
  93     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
  94     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
  95 };
  96
  97 static const uint8_t non_linear_qscale[32] = {
  98      0,  1,  2,  3,  4,  5,   6,   7,
  99      8, 10, 12, 14, 16, 18,  20,  22,
 100     24, 28, 32, 36, 40, 44,  48,  52,
 101     56, 64, 72, 80, 88, 96, 104, 112,
 102 };
 103
 104 /* as H.263, but only 17 codes */
 105 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 106 {
 107     int code, sign, val, shift;
 108
 109     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
 110     if (code == 0)
 111         return pred;
 112     if (code < 0)
 113         return 0xffff;
 114
 115     sign  = get_bits1(&s->gb);
 116     shift = fcode - 1;
 117     val   = code;
 118     if (shift) {
 119         val  = (val - 1) << shift;
 120         val |= get_bits(&s->gb, shift);
 121         val++;
 122     }
 123     if (sign)
 124         val = -val;
 125     val += pred;
 126
 127     /* modulo decoding */
 128     return sign_extend(val, 5 + shift);
 129 }
 130
 131 #define check_scantable_index(ctx, x)                                         \
 132     do {                                                                      \
 133         if ((x) > 63) {                                                       \
 134             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
 135                    ctx->mb_x, ctx->mb_y);                                     \
 136             return AVERROR_INVALIDDATA;                                       \
 137         }                                                                     \
 138     } while (0)
 139
 140 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
 141                                            int16_t *block, int n)
 142 {
 143     int level, dc, diff, i, j, run;
 144     int component;
 145     RLTable *rl                  = &ff_rl_mpeg1;
 146     uint8_t *const scantable     = s->intra_scantable.permutated;
 147     const uint16_t *quant_matrix = s->intra_matrix;
 148     const int qscale             = s->qscale;
 149
 150     /* DC coefficient */
 151     component = (n <= 3 ? 0 : n - 4 + 1);
 152     diff = decode_dc(&s->gb, component);
 153     if (diff >= 0xffff)
 154         return AVERROR_INVALIDDATA;
 155     dc  = s->last_dc[component];
 156     dc += diff;
 157     s->last_dc[component] = dc;
 158     block[0] = dc * quant_matrix[0];
 159     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
 160     i = 0;
 161     {
 162         OPEN_READER(re, &s->gb);
 163         UPDATE_CACHE(re, &s->gb);
 164         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 165             goto end;
 166
 167         /* now quantify & encode AC coefficients */
 168         for (;;) {
 169             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 170                        TEX_VLC_BITS, 2, 0);
 171
 172             if (level != 0) {
 173                 i += run;
 174                 check_scantable_index(s, i);
 175                 j = scantable[i];
 176                 level = (level * qscale * quant_matrix[j]) >> 4;
 177                 level = (level - 1) | 1;
 178                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 179                         SHOW_SBITS(re, &s->gb, 1);
 180                 SKIP_BITS(re, &s->gb, 1);
 181             } else {
 182                 /* escape */
 183                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 184                 LAST_SKIP_BITS(re, &s->gb, 6);
 185                 UPDATE_CACHE(re, &s->gb);
 186                 level = SHOW_SBITS(re, &s->gb, 8);
 187                 SKIP_BITS(re, &s->gb, 8);
 188                 if (level == -128) {
 189                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 190                     SKIP_BITS(re, &s->gb, 8);
 191                 } else if (level == 0) {
 192                     level = SHOW_UBITS(re, &s->gb, 8);
 193                     SKIP_BITS(re, &s->gb, 8);
 194                 }
 195                 i += run;
 196                 check_scantable_index(s, i);
 197                 j = scantable[i];
 198                 if (level < 0) {
 199                     level = -level;
 200                     level = (level * qscale * quant_matrix[j]) >> 4;
 201                     level = (level - 1) | 1;
 202                     level = -level;
 203                 } else {
 204                     level = (level * qscale * quant_matrix[j]) >> 4;
 205                     level = (level - 1) | 1;
 206                 }
 207             }
 208
 209             block[j] = level;
 210             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 211                break;
 212
 213             UPDATE_CACHE(re, &s->gb);
 214         }
 215 end:
 216         LAST_SKIP_BITS(re, &s->gb, 2);
 217         CLOSE_READER(re, &s->gb);
 218     }
 219     s->block_last_index[n] = i;
 220     return 0;
 221 }
 222
 223 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 224 {
 225     return mpeg1_decode_block_intra(s, block, n);
 226 }
 227
 228 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 229                                            int16_t *block, int n)
 230 {
 231     int level, i, j, run;
 232     RLTable *rl                  = &ff_rl_mpeg1;
 233     uint8_t *const scantable     = s->intra_scantable.permutated;
 234     const uint16_t *quant_matrix = s->inter_matrix;
 235     const int qscale             = s->qscale;
 236
 237     {
 238         OPEN_READER(re, &s->gb);
 239         i = -1;
 240         // special case for first coefficient, no need to add second VLC table
 241         UPDATE_CACHE(re, &s->gb);
 242         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 243             level = (3 * qscale * quant_matrix[0]) >> 5;
 244             level = (level - 1) | 1;
 245             if (GET_CACHE(re, &s->gb) & 0x40000000)
 246                 level = -level;
 247             block[0] = level;
 248             i++;
 249             SKIP_BITS(re, &s->gb, 2);
 250             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 251                 goto end;
 252         }
 253         /* now quantify & encode AC coefficients */
 254         for (;;) {
 255             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 256                        TEX_VLC_BITS, 2, 0);
 257
 258             if (level != 0) {
 259                 i += run;
 260                 check_scantable_index(s, i);
 261                 j = scantable[i];
 262                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 263                 level = (level - 1) | 1;
 264                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 265                         SHOW_SBITS(re, &s->gb, 1);
 266                 SKIP_BITS(re, &s->gb, 1);
 267             } else {
 268                 /* escape */
 269                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 270                 LAST_SKIP_BITS(re, &s->gb, 6);
 271                 UPDATE_CACHE(re, &s->gb);
 272                 level = SHOW_SBITS(re, &s->gb, 8);
 273                 SKIP_BITS(re, &s->gb, 8);
 274                 if (level == -128) {
 275                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 276                     SKIP_BITS(re, &s->gb, 8);
 277                 } else if (level == 0) {
 278                     level = SHOW_UBITS(re, &s->gb, 8);
 279                     SKIP_BITS(re, &s->gb, 8);
 280                 }
 281                 i += run;
 282                 check_scantable_index(s, i);
 283                 j = scantable[i];
 284                 if (level < 0) {
 285                     level = -level;
 286                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 287                     level = (level - 1) | 1;
 288                     level = -level;
 289                 } else {
 290                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 291                     level = (level - 1) | 1;
 292                 }
 293             }
 294
 295             block[j] = level;
 296             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 297                 break;
 298             UPDATE_CACHE(re, &s->gb);
 299         }
 300 end:
 301         LAST_SKIP_BITS(re, &s->gb, 2);
 302         CLOSE_READER(re, &s->gb);
 303     }
 304     s->block_last_index[n] = i;
 305     return 0;
 306 }
 307
 308 /**
 309  * Note: this function can read out of range and crash for corrupt streams.
 310  * Changing this would eat up any speed benefits it has.
 311  * Do not use "fast" flag if you need the code to be robust.
 312  */
 313 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
 314                                                 int16_t *block, int n)
 315 {
 316     int level, i, j, run;
 317     RLTable *rl              = &ff_rl_mpeg1;
 318     uint8_t *const scantable = s->intra_scantable.permutated;
 319     const int qscale         = s->qscale;
 320
 321     {
 322         OPEN_READER(re, &s->gb);
 323         i = -1;
 324         // Special case for first coefficient, no need to add second VLC table.
 325         UPDATE_CACHE(re, &s->gb);
 326         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 327             level = (3 * qscale) >> 1;
 328             level = (level - 1) | 1;
 329             if (GET_CACHE(re, &s->gb) & 0x40000000)
 330                 level = -level;
 331             block[0] = level;
 332             i++;
 333             SKIP_BITS(re, &s->gb, 2);
 334             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 335                 goto end;
 336         }
 337
 338         /* now quantify & encode AC coefficients */
 339         for (;;) {
 340             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 341                        TEX_VLC_BITS, 2, 0);
 342
 343             if (level != 0) {
 344                 i += run;
 345                 check_scantable_index(s, i);
 346                 j = scantable[i];
 347                 level = ((level * 2 + 1) * qscale) >> 1;
 348                 level = (level - 1) | 1;
 349                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 350                         SHOW_SBITS(re, &s->gb, 1);
 351                 SKIP_BITS(re, &s->gb, 1);
 352             } else {
 353                 /* escape */
 354                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 355                 LAST_SKIP_BITS(re, &s->gb, 6);
 356                 UPDATE_CACHE(re, &s->gb);
 357                 level = SHOW_SBITS(re, &s->gb, 8);
 358                 SKIP_BITS(re, &s->gb, 8);
 359                 if (level == -128) {
 360                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
 361                     SKIP_BITS(re, &s->gb, 8);
 362                 } else if (level == 0) {
 363                     level = SHOW_UBITS(re, &s->gb, 8);
 364                     SKIP_BITS(re, &s->gb, 8);
 365                 }
 366                 i += run;
 367                 check_scantable_index(s, i);
 368                 j = scantable[i];
 369                 if (level < 0) {
 370                     level = -level;
 371                     level = ((level * 2 + 1) * qscale) >> 1;
 372                     level = (level - 1) | 1;
 373                     level = -level;
 374                 } else {
 375                     level = ((level * 2 + 1) * qscale) >> 1;
 376                     level = (level - 1) | 1;
 377                 }
 378             }
 379
 380             block[j] = level;
 381             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 382                 break;
 383             UPDATE_CACHE(re, &s->gb);
 384         }
 385 end:
 386         LAST_SKIP_BITS(re, &s->gb, 2);
 387         CLOSE_READER(re, &s->gb);
 388     }
 389     s->block_last_index[n] = i;
 390     return 0;
 391 }
 392
 393 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 394                                                int16_t *block, int n)
 395 {
 396     int level, i, j, run;
 397     RLTable *rl = &ff_rl_mpeg1;
 398     uint8_t *const scantable = s->intra_scantable.permutated;
 399     const uint16_t *quant_matrix;
 400     const int qscale = s->qscale;
 401     int mismatch;
 402
 403     mismatch = 1;
 404
 405     {
 406         OPEN_READER(re, &s->gb);
 407         i = -1;
 408         if (n < 4)
 409             quant_matrix = s->inter_matrix;
 410         else
 411             quant_matrix = s->chroma_inter_matrix;
 412
 413         // Special case for first coefficient, no need to add second VLC table.
 414         UPDATE_CACHE(re, &s->gb);
 415         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 416             level = (3 * qscale * quant_matrix[0]) >> 5;
 417             if (GET_CACHE(re, &s->gb) & 0x40000000)
 418                 level = -level;
 419             block[0]  = level;
 420             mismatch ^= level;
 421             i++;
 422             SKIP_BITS(re, &s->gb, 2);
 423             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 424                 goto end;
 425         }
 426
 427         /* now quantify & encode AC coefficients */
 428         for (;;) {
 429             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 430                        TEX_VLC_BITS, 2, 0);
 431
 432             if (level != 0) {
 433                 i += run;
 434                 check_scantable_index(s, i);
 435                 j = scantable[i];
 436                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 437                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 438                         SHOW_SBITS(re, &s->gb, 1);
 439                 SKIP_BITS(re, &s->gb, 1);
 440             } else {
 441                 /* escape */
 442                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 443                 LAST_SKIP_BITS(re, &s->gb, 6);
 444                 UPDATE_CACHE(re, &s->gb);
 445                 level = SHOW_SBITS(re, &s->gb, 12);
 446                 SKIP_BITS(re, &s->gb, 12);
 447
 448                 i += run;
 449                 check_scantable_index(s, i);
 450                 j = scantable[i];
 451                 if (level < 0) {
 452                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 453                     level = -level;
 454                 } else {
 455                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 456                 }
 457             }
 458
 459             mismatch ^= level;
 460             block[j]  = level;
 461             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 462                 break;
 463             UPDATE_CACHE(re, &s->gb);
 464         }
 465 end:
 466         LAST_SKIP_BITS(re, &s->gb, 2);
 467         CLOSE_READER(re, &s->gb);
 468     }
 469     block[63] ^= (mismatch & 1);
 470
 471     s->block_last_index[n] = i;
 472     return 0;
 473 }
 474
 475 /**
 476  * Note: this function can read out of range and crash for corrupt streams.
 477  * Changing this would eat up any speed benefits it has.
 478  * Do not use "fast" flag if you need the code to be robust.
 479  */
 480 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 481                                                     int16_t *block, int n)
 482 {
 483     int level, i, j, run;
 484     RLTable *rl              = &ff_rl_mpeg1;
 485     uint8_t *const scantable = s->intra_scantable.permutated;
 486     const int qscale         = s->qscale;
 487     OPEN_READER(re, &s->gb);
 488     i = -1;
 489
 490     // special case for first coefficient, no need to add second VLC table
 491     UPDATE_CACHE(re, &s->gb);
 492     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
 493         level = (3 * qscale) >> 1;
 494         if (GET_CACHE(re, &s->gb) & 0x40000000)
 495             level = -level;
 496         block[0] = level;
 497         i++;
 498         SKIP_BITS(re, &s->gb, 2);
 499         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
 500             goto end;
 501     }
 502
 503     /* now quantify & encode AC coefficients */
 504     for (;;) {
 505         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 506
 507         if (level != 0) {
 508             i += run;
 509             j = scantable[i];
 510             level = ((level * 2 + 1) * qscale) >> 1;
 511             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 512                     SHOW_SBITS(re, &s->gb, 1);
 513             SKIP_BITS(re, &s->gb, 1);
 514         } else {
 515             /* escape */
 516             run = SHOW_UBITS(re, &s->gb, 6) + 1;
 517             LAST_SKIP_BITS(re, &s->gb, 6);
 518             UPDATE_CACHE(re, &s->gb);
 519             level = SHOW_SBITS(re, &s->gb, 12);
 520             SKIP_BITS(re, &s->gb, 12);
 521
 522             i += run;
 523             j = scantable[i];
 524             if (level < 0) {
 525                 level = ((-level * 2 + 1) * qscale) >> 1;
 526                 level = -level;
 527             } else {
 528                 level = ((level * 2 + 1) * qscale) >> 1;
 529             }
 530         }
 531
 532         block[j] = level;
 533         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
 534             break;
 535
 536         UPDATE_CACHE(re, &s->gb);
 537     }
 538 end:
 539     LAST_SKIP_BITS(re, &s->gb, 2);
 540     CLOSE_READER(re, &s->gb);
 541     s->block_last_index[n] = i;
 542     return 0;
 543 }
 544
 545 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
 546                                            int16_t *block, int n)
 547 {
 548     int level, dc, diff, i, j, run;
 549     int component;
 550     RLTable *rl;
 551     uint8_t *const scantable = s->intra_scantable.permutated;
 552     const uint16_t *quant_matrix;
 553     const int qscale = s->qscale;
 554     int mismatch;
 555
 556     /* DC coefficient */
 557     if (n < 4) {
 558         quant_matrix = s->intra_matrix;
 559         component    = 0;
 560     } else {
 561         quant_matrix = s->chroma_intra_matrix;
 562         component    = (n & 1) + 1;
 563     }
 564     diff = decode_dc(&s->gb, component);
 565     if (diff >= 0xffff)
 566         return AVERROR_INVALIDDATA;
 567     dc  = s->last_dc[component];
 568     dc += diff;
 569     s->last_dc[component] = dc;
 570     block[0] = dc << (3 - s->intra_dc_precision);
 571     av_dlog(s->avctx, "dc=%d\n", block[0]);
 572     mismatch = block[0] ^ 1;
 573     i = 0;
 574     if (s->intra_vlc_format)
 575         rl = &ff_rl_mpeg2;
 576     else
 577         rl = &ff_rl_mpeg1;
 578
 579     {
 580         OPEN_READER(re, &s->gb);
 581         /* now quantify & encode AC coefficients */
 582         for (;;) {
 583             UPDATE_CACHE(re, &s->gb);
 584             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 585                        TEX_VLC_BITS, 2, 0);
 586
 587             if (level == 127) {
 588                 break;
 589             } else if (level != 0) {
 590                 i += run;
 591                 check_scantable_index(s, i);
 592                 j = scantable[i];
 593                 level = (level * qscale * quant_matrix[j]) >> 4;
 594                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 595                         SHOW_SBITS(re, &s->gb, 1);
 596                 LAST_SKIP_BITS(re, &s->gb, 1);
 597             } else {
 598                 /* escape */
 599                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 600                 LAST_SKIP_BITS(re, &s->gb, 6);
 601                 UPDATE_CACHE(re, &s->gb);
 602                 level = SHOW_SBITS(re, &s->gb, 12);
 603                 SKIP_BITS(re, &s->gb, 12);
 604                 i += run;
 605                 check_scantable_index(s, i);
 606                 j = scantable[i];
 607                 if (level < 0) {
 608                     level = (-level * qscale * quant_matrix[j]) >> 4;
 609                     level = -level;
 610                 } else {
 611                     level = (level * qscale * quant_matrix[j]) >> 4;
 612                 }
 613             }
 614
 615             mismatch ^= level;
 616             block[j]  = level;
 617         }
 618         CLOSE_READER(re, &s->gb);
 619     }
 620     block[63] ^= mismatch & 1;
 621
 622     s->block_last_index[n] = i;
 623     return 0;
 624 }
 625
 626 /**
 627  * Note: this function can read out of range and crash for corrupt streams.
 628  * Changing this would eat up any speed benefits it has.
 629  * Do not use "fast" flag if you need the code to be robust.
 630  */
 631 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
 632                                                 int16_t *block, int n)
 633 {
 634     int level, dc, diff, i, j, run;
 635     int component;
 636     RLTable *rl;
 637     uint8_t *const scantable = s->intra_scantable.permutated;
 638     const uint16_t *quant_matrix;
 639     const int qscale = s->qscale;
 640
 641     /* DC coefficient */
 642     if (n < 4) {
 643         quant_matrix = s->intra_matrix;
 644         component    = 0;
 645     } else {
 646         quant_matrix = s->chroma_intra_matrix;
 647         component    = (n & 1) + 1;
 648     }
 649     diff = decode_dc(&s->gb, component);
 650     if (diff >= 0xffff)
 651         return AVERROR_INVALIDDATA;
 652     dc = s->last_dc[component];
 653     dc += diff;
 654     s->last_dc[component] = dc;
 655     block[0] = dc << (3 - s->intra_dc_precision);
 656     i = 0;
 657     if (s->intra_vlc_format)
 658         rl = &ff_rl_mpeg2;
 659     else
 660         rl = &ff_rl_mpeg1;
 661
 662     {
 663         OPEN_READER(re, &s->gb);
 664         /* now quantify & encode AC coefficients */
 665         for (;;) {
 666             UPDATE_CACHE(re, &s->gb);
 667             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
 668                        TEX_VLC_BITS, 2, 0);
 669
 670             if (level >= 64 || i > 63) {
 671                 break;
 672             } else if (level != 0) {
 673                 i += run;
 674                 j = scantable[i];
 675                 level = (level * qscale * quant_matrix[j]) >> 4;
 676                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
 677                         SHOW_SBITS(re, &s->gb, 1);
 678                 LAST_SKIP_BITS(re, &s->gb, 1);
 679             } else {
 680                 /* escape */
 681                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
 682                 LAST_SKIP_BITS(re, &s->gb, 6);
 683                 UPDATE_CACHE(re, &s->gb);
 684                 level = SHOW_SBITS(re, &s->gb, 12);
 685                 SKIP_BITS(re, &s->gb, 12);
 686                 i += run;
 687                 j = scantable[i];
 688                 if (level < 0) {
 689                     level = (-level * qscale * quant_matrix[j]) >> 4;
 690                     level = -level;
 691                 } else {
 692                     level = (level * qscale * quant_matrix[j]) >> 4;
 693                 }
 694             }
 695
 696             block[j] = level;
 697         }
 698         CLOSE_READER(re, &s->gb);
 699     }
 700
 701     s->block_last_index[n] = i;
 702     return 0;
 703 }
 704
 705 /******************************************/
 706 /* decoding */
 707
 708 static inline int get_dmv(MpegEncContext *s)
 709 {
 710     if (get_bits1(&s->gb))
 711         return 1 - (get_bits1(&s->gb) << 1);
 712     else
 713         return 0;
 714 }
 715
 716 static inline int get_qscale(MpegEncContext *s)
 717 {
 718     int qscale = get_bits(&s->gb, 5);
 719     if (s->q_scale_type)
 720         return non_linear_qscale[qscale];
 721     else
 722         return qscale << 1;
 723 }
 724
 725
 726 /* motion type (for MPEG-2) */
 727 #define MT_FIELD 1
 728 #define MT_FRAME 2
 729 #define MT_16X8  2
 730 #define MT_DMV   3
 731
 732 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 733 {
 734     int i, j, k, cbp, val, mb_type, motion_type;
 735     const int mb_block_count = 4 + (1 << s->chroma_format);
 736     int ret;
 737
 738     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 739
 740     av_assert2(s->mb_skipped == 0);
 741
 742     if (s->mb_skip_run-- != 0) {
 743         if (s->pict_type == AV_PICTURE_TYPE_P) {
 744             s->mb_skipped = 1;
 745             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 746                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 747         } else {
 748             int mb_type;
 749
 750             if (s->mb_x)
 751                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 752             else
 753                 // FIXME not sure if this is allowed in MPEG at all
 754                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
 755             if (IS_INTRA(mb_type)) {
 756                 av_log(s->avctx, AV_LOG_ERROR, "skip with previntra\n");
 757                 return AVERROR_INVALIDDATA;
 758             }
 759             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
 760                 mb_type | MB_TYPE_SKIP;
 761
 762             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 763                 s->mb_skipped = 1;
 764         }
 765
 766         return 0;
 767     }
 768
 769     switch (s->pict_type) {
 770     default:
 771     case AV_PICTURE_TYPE_I:
 772         if (get_bits1(&s->gb) == 0) {
 773             if (get_bits1(&s->gb) == 0) {
 774                 av_log(s->avctx, AV_LOG_ERROR,
 775                        "invalid mb type in I Frame at %d %d\n",
 776                        s->mb_x, s->mb_y);
 777                 return AVERROR_INVALIDDATA;
 778             }
 779             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 780         } else {
 781             mb_type = MB_TYPE_INTRA;
 782         }
 783         break;
 784     case AV_PICTURE_TYPE_P:
 785         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 786         if (mb_type < 0) {
 787             av_log(s->avctx, AV_LOG_ERROR,
 788                    "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 789             return AVERROR_INVALIDDATA;
 790         }
 791         mb_type = ptype2mb_type[mb_type];
 792         break;
 793     case AV_PICTURE_TYPE_B:
 794         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 795         if (mb_type < 0) {
 796             av_log(s->avctx, AV_LOG_ERROR,
 797                    "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 798             return AVERROR_INVALIDDATA;
 799         }
 800         mb_type = btype2mb_type[mb_type];
 801         break;
 802     }
 803     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
 804 //    motion_type = 0; /* avoid warning */
 805     if (IS_INTRA(mb_type)) {
 806         s->bdsp.clear_blocks(s->block[0]);
 807
 808         if (!s->chroma_y_shift)
 809             s->bdsp.clear_blocks(s->block[6]);
 810
 811         /* compute DCT type */
 812         // FIXME: add an interlaced_dct coded var?
 813         if (s->picture_structure == PICT_FRAME &&
 814             !s->frame_pred_frame_dct)
 815             s->interlaced_dct = get_bits1(&s->gb);
 816
 817         if (IS_QUANT(mb_type))
 818             s->qscale = get_qscale(s);
 819
 820         if (s->concealment_motion_vectors) {
 821             /* just parse them */
 822             if (s->picture_structure != PICT_FRAME)
 823                 skip_bits1(&s->gb);  /* field select */
 824
 825             s->mv[0][0][0]      =
 826             s->last_mv[0][0][0] =
 827             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
 828                                                      s->last_mv[0][0][0]);
 829             s->mv[0][0][1]      =
 830             s->last_mv[0][0][1] =
 831             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
 832                                                      s->last_mv[0][0][1]);
 833
 834             skip_bits1(&s->gb); /* marker */
 835         } else {
 836             /* reset mv prediction */
 837             memset(s->last_mv, 0, sizeof(s->last_mv));
 838         }
 839         s->mb_intra = 1;
 840         // if 1, we memcpy blocks in xvmcvideo
 841         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
 842             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 843
 844         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 845             if (s->flags2 & CODEC_FLAG2_FAST) {
 846                 for (i = 0; i < 6; i++)
 847                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 848             } else {
 849                 for (i = 0; i < mb_block_count; i++)
 850                     if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 851                         return ret;
 852             }
 853         } else {
 854             for (i = 0; i < 6; i++)
 855                 if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0)
 856                     return ret;
 857         }
 858     } else {
 859         if (mb_type & MB_TYPE_ZERO_MV) {
 860             av_assert2(mb_type & MB_TYPE_CBP);
 861
 862             s->mv_dir = MV_DIR_FORWARD;
 863             if (s->picture_structure == PICT_FRAME) {
 864                 if (s->picture_structure == PICT_FRAME
 865                     && !s->frame_pred_frame_dct)
 866                     s->interlaced_dct = get_bits1(&s->gb);
 867                 s->mv_type = MV_TYPE_16X16;
 868             } else {
 869                 s->mv_type            = MV_TYPE_FIELD;
 870                 mb_type              |= MB_TYPE_INTERLACED;
 871                 s->field_select[0][0] = s->picture_structure - 1;
 872             }
 873
 874             if (IS_QUANT(mb_type))
 875                 s->qscale = get_qscale(s);
 876
 877             s->last_mv[0][0][0] = 0;
 878             s->last_mv[0][0][1] = 0;
 879             s->last_mv[0][1][0] = 0;
 880             s->last_mv[0][1][1] = 0;
 881             s->mv[0][0][0]      = 0;
 882             s->mv[0][0][1]      = 0;
 883         } else {
 884             av_assert2(mb_type & MB_TYPE_L0L1);
 885             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 886             /* get additional motion vector type */
 887             if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) {
 888                 motion_type = MT_FRAME;
 889             } else {
 890                 motion_type = get_bits(&s->gb, 2);
 891                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 892                     s->interlaced_dct = get_bits1(&s->gb);
 893             }
 894
 895             if (IS_QUANT(mb_type))
 896                 s->qscale = get_qscale(s);
 897
 898             /* motion vectors */
 899             s->mv_dir = (mb_type >> 13) & 3;
 900             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
 901             switch (motion_type) {
 902             case MT_FRAME: /* or MT_16X8 */
 903                 if (s->picture_structure == PICT_FRAME) {
 904                     mb_type   |= MB_TYPE_16x16;
 905                     s->mv_type = MV_TYPE_16X16;
 906                     for (i = 0; i < 2; i++) {
 907                         if (USES_LIST(mb_type, i)) {
 908                             /* MT_FRAME */
 909                             s->mv[i][0][0]      =
 910                             s->last_mv[i][0][0] =
 911                             s->last_mv[i][1][0] =
 912                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 913                                                    s->last_mv[i][0][0]);
 914                             s->mv[i][0][1]      =
 915                             s->last_mv[i][0][1] =
 916                             s->last_mv[i][1][1] =
 917                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 918                                                    s->last_mv[i][0][1]);
 919                             /* full_pel: only for MPEG-1 */
 920                             if (s->full_pel[i]) {
 921                                 s->mv[i][0][0] <<= 1;
 922                                 s->mv[i][0][1] <<= 1;
 923                             }
 924                         }
 925                     }
 926                 } else {
 927                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 928                     s->mv_type = MV_TYPE_16X8;
 929                     for (i = 0; i < 2; i++) {
 930                         if (USES_LIST(mb_type, i)) {
 931                             /* MT_16X8 */
 932                             for (j = 0; j < 2; j++) {
 933                                 s->field_select[i][j] = get_bits1(&s->gb);
 934                                 for (k = 0; k < 2; k++) {
 935                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 936                                                              s->last_mv[i][j][k]);
 937                                     s->last_mv[i][j][k] = val;
 938                                     s->mv[i][j][k]      = val;
 939                                 }
 940                             }
 941                         }
 942                     }
 943                 }
 944                 break;
 945             case MT_FIELD:
 946                 s->mv_type = MV_TYPE_FIELD;
 947                 if (s->picture_structure == PICT_FRAME) {
 948                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 949                     for (i = 0; i < 2; i++) {
 950                         if (USES_LIST(mb_type, i)) {
 951                             for (j = 0; j < 2; j++) {
 952                                 s->field_select[i][j] = get_bits1(&s->gb);
 953                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 954                                                          s->last_mv[i][j][0]);
 955                                 s->last_mv[i][j][0] = val;
 956                                 s->mv[i][j][0]      = val;
 957                                 av_dlog(s->avctx, "fmx=%d\n", val);
 958                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 959                                                          s->last_mv[i][j][1] >> 1);
 960                                 s->last_mv[i][j][1] = val << 1;
 961                                 s->mv[i][j][1]      = val;
 962                                 av_dlog(s->avctx, "fmy=%d\n", val);
 963                             }
 964                         }
 965                     }
 966                 } else {
 967                     av_assert0(!s->progressive_sequence);
 968                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 969                     for (i = 0; i < 2; i++) {
 970                         if (USES_LIST(mb_type, i)) {
 971                             s->field_select[i][0] = get_bits1(&s->gb);
 972                             for (k = 0; k < 2; k++) {
 973                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 974                                                          s->last_mv[i][0][k]);
 975                                 s->last_mv[i][0][k] = val;
 976                                 s->last_mv[i][1][k] = val;
 977                                 s->mv[i][0][k]      = val;
 978                             }
 979                         }
 980                     }
 981                 }
 982                 break;
 983             case MT_DMV:
 984                 if (s->progressive_sequence){
 985                     av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
 986                     return AVERROR_INVALIDDATA;
 987                 }
 988                 s->mv_type = MV_TYPE_DMV;
 989                 for (i = 0; i < 2; i++) {
 990                     if (USES_LIST(mb_type, i)) {
 991                         int dmx, dmy, mx, my, m;
 992                         const int my_shift = s->picture_structure == PICT_FRAME;
 993
 994                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 995                                                 s->last_mv[i][0][0]);
 996                         s->last_mv[i][0][0] = mx;
 997                         s->last_mv[i][1][0] = mx;
 998                         dmx = get_dmv(s);
 999                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1000                                                  s->last_mv[i][0][1] >> my_shift);
1001                         dmy = get_dmv(s);
1002
1003
1004                         s->last_mv[i][0][1] = my << my_shift;
1005                         s->last_mv[i][1][1] = my << my_shift;
1006
1007                         s->mv[i][0][0] = mx;
1008                         s->mv[i][0][1] = my;
1009                         s->mv[i][1][0] = mx; // not used
1010                         s->mv[i][1][1] = my; // not used
1011
1012                         if (s->picture_structure == PICT_FRAME) {
1013                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1014
1015                             // m = 1 + 2 * s->top_field_first;
1016                             m = s->top_field_first ? 1 : 3;
1017
1018                             /* top -> top pred */
1019                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1020                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1021                             m = 4 - m;
1022                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1023                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1024                         } else {
1025                             mb_type |= MB_TYPE_16x16;
1026
1027                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1028                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1029                             if (s->picture_structure == PICT_TOP_FIELD)
1030                                 s->mv[i][2][1]--;
1031                             else
1032                                 s->mv[i][2][1]++;
1033                         }
1034                     }
1035                 }
1036                 break;
1037             default:
1038                 av_log(s->avctx, AV_LOG_ERROR,
1039                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1040                 return AVERROR_INVALIDDATA;
1041             }
1042         }
1043
1044         s->mb_intra = 0;
1045         if (HAS_CBP(mb_type)) {
1046             s->bdsp.clear_blocks(s->block[0]);
1047
1048             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1049             if (mb_block_count > 6) {
1050                 cbp <<= mb_block_count - 6;
1051                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
1052                 s->bdsp.clear_blocks(s->block[6]);
1053             }
1054             if (cbp <= 0) {
1055                 av_log(s->avctx, AV_LOG_ERROR,
1056                        "invalid cbp %d at %d %d\n", cbp, s->mb_x, s->mb_y);
1057                 return AVERROR_INVALIDDATA;
1058             }
1059
1060             // if 1, we memcpy blocks in xvmcvideo
1061             if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1062                 ff_xvmc_pack_pblocks(s, cbp);
1063
1064             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1065                 if (s->flags2 & CODEC_FLAG2_FAST) {
1066                     for (i = 0; i < 6; i++) {
1067                         if (cbp & 32)
1068                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1069                         else
1070                             s->block_last_index[i] = -1;
1071                         cbp += cbp;
1072                     }
1073                 } else {
1074                     cbp <<= 12 - mb_block_count;
1075
1076                     for (i = 0; i < mb_block_count; i++) {
1077                         if (cbp & (1 << 11)) {
1078                             if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
1079                                 return ret;
1080                         } else {
1081                             s->block_last_index[i] = -1;
1082                         }
1083                         cbp += cbp;
1084                     }
1085                 }
1086             } else {
1087                 if (s->flags2 & CODEC_FLAG2_FAST) {
1088                     for (i = 0; i < 6; i++) {
1089                         if (cbp & 32)
1090                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1091                         else
1092                             s->block_last_index[i] = -1;
1093                         cbp += cbp;
1094                     }
1095                 } else {
1096                     for (i = 0; i < 6; i++) {
1097                         if (cbp & 32) {
1098                             if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
1099                                 return ret;
1100                         } else {
1101                             s->block_last_index[i] = -1;
1102                         }
1103                         cbp += cbp;
1104                     }
1105                 }
1106             }
1107         } else {
1108             for (i = 0; i < 12; i++)
1109                 s->block_last_index[i] = -1;
1110         }
1111     }
1112
1113     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1114
1115     return 0;
1116 }
1117
1118 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1119 {
1120     Mpeg1Context *s    = avctx->priv_data;
1121     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1122
1123     ff_mpv_decode_defaults(s2);
1124
1125     if (   avctx->codec_tag != AV_RL32("VCR2")
1126         && avctx->codec_tag != AV_RL32("BW10"))
1127         avctx->coded_width = avctx->coded_height = 0; // do not trust dimensions from input
1128     ff_mpv_decode_init(s2, avctx);
1129
1130     s->mpeg_enc_ctx.avctx  = avctx;
1131
1132     /* we need some permutation to store matrices,
1133      * until the decoder sets the real permutation. */
1134     ff_mpv_idct_init(s2);
1135     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1136     ff_mpeg12_init_vlcs();
1137
1138     s->mpeg_enc_ctx_allocated      = 0;
1139     s->mpeg_enc_ctx.picture_number = 0;
1140     s->repeat_field                = 0;
1141     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1142     avctx->color_range             = AVCOL_RANGE_MPEG;
1143     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1144         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1145     else
1146         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1147     return 0;
1148 }
1149
1150 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1151                                              const AVCodecContext *avctx_from)
1152 {
1153     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1154     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1155     int err;
1156
1157     if (avctx == avctx_from               ||
1158         !ctx_from->mpeg_enc_ctx_allocated ||
1159         !s1->context_initialized)
1160         return 0;
1161
1162     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1163     if (err)
1164         return err;
1165
1166     if (!ctx->mpeg_enc_ctx_allocated)
1167         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1168
1169     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1170         s->picture_number++;
1171
1172     return 0;
1173 }
1174
1175 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1176                                  const uint8_t *new_perm)
1177 {
1178     uint16_t temp_matrix[64];
1179     int i;
1180
1181     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1182
1183     for (i = 0; i < 64; i++)
1184         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1185 }
1186
1187 static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1188 #if CONFIG_MPEG1_XVMC_HWACCEL
1189     AV_PIX_FMT_XVMC,
1190 #endif
1191 #if CONFIG_MPEG1_VDPAU_HWACCEL
1192     AV_PIX_FMT_VDPAU_MPEG1,
1193     AV_PIX_FMT_VDPAU,
1194 #endif
1195     AV_PIX_FMT_YUV420P,
1196     AV_PIX_FMT_NONE
1197 };
1198
1199 static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1200 #if CONFIG_MPEG2_XVMC_HWACCEL
1201     AV_PIX_FMT_XVMC,
1202 #endif
1203 #if CONFIG_MPEG2_VDPAU_HWACCEL
1204     AV_PIX_FMT_VDPAU_MPEG2,
1205     AV_PIX_FMT_VDPAU,
1206 #endif
1207 #if CONFIG_MPEG2_DXVA2_HWACCEL
1208     AV_PIX_FMT_DXVA2_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 (s->chroma_format < 2)
1238         pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1239                                 mpeg1_hwaccel_pixfmt_list_420 :
1240                                 mpeg2_hwaccel_pixfmt_list_420;
1241     else if (s->chroma_format == 2)
1242         pix_fmts = mpeg12_pixfmt_list_422;
1243     else
1244         pix_fmts = mpeg12_pixfmt_list_444;
1245
1246     return ff_thread_get_format(avctx, pix_fmts);
1247 }
1248
1249 static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
1250 {
1251     // until then pix_fmt may be changed right after codec init
1252     if (avctx->hwaccel || uses_vdpau(avctx))
1253         if (avctx->idct_algo == FF_IDCT_AUTO)
1254             avctx->idct_algo = FF_IDCT_SIMPLE;
1255
1256     if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
1257         Mpeg1Context *s1 = avctx->priv_data;
1258         MpegEncContext *s = &s1->mpeg_enc_ctx;
1259
1260         s->pack_pblocks = 1;
1261 #if FF_API_XVMC
1262         avctx->xvmc_acceleration = 2;
1263 #endif /* FF_API_XVMC */
1264     }
1265 }
1266
1267 /* Call this function when we know all parameters.
1268  * It may be called in different places for MPEG-1 and MPEG-2. */
1269 static int mpeg_decode_postinit(AVCodecContext *avctx)
1270 {
1271     Mpeg1Context *s1  = avctx->priv_data;
1272     MpegEncContext *s = &s1->mpeg_enc_ctx;
1273     uint8_t old_permutation[64];
1274     int ret;
1275
1276     if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1277         // MPEG-1 aspect
1278         avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1279     } else { // MPEG-2
1280         // MPEG-2 aspect
1281         if (s->aspect_ratio_info > 1) {
1282             AVRational dar =
1283                 av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1284                                   (AVRational) { s1->pan_scan.width,
1285                                                  s1->pan_scan.height }),
1286                          (AVRational) { s->width, s->height });
1287
1288             /* We ignore the spec here and guess a bit as reality does not
1289              * match the spec, see for example res_change_ffmpeg_aspect.ts
1290              * and sequence-display-aspect.mpg.
1291              * issue1613, 621, 562 */
1292             if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1293                 (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1294                  av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1295                 s->avctx->sample_aspect_ratio =
1296                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1297                              (AVRational) { s->width, s->height });
1298             } else {
1299                 s->avctx->sample_aspect_ratio =
1300                     av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1301                              (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1302 // issue1613 4/3 16/9 -> 16/9
1303 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1304 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1305 //                s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1306                 av_dlog(avctx, "A %d/%d\n",
1307                         ff_mpeg2_aspect[s->aspect_ratio_info].num,
1308                         ff_mpeg2_aspect[s->aspect_ratio_info].den);
1309                 av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1310                         s->avctx->sample_aspect_ratio.den);
1311             }
1312         } else {
1313             s->avctx->sample_aspect_ratio =
1314                 ff_mpeg2_aspect[s->aspect_ratio_info];
1315         }
1316     } // MPEG-2
1317
1318     ff_set_sar(s->avctx, s->avctx->sample_aspect_ratio);
1319
1320     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1321         avctx->coded_width       != s->width                ||
1322         avctx->coded_height      != s->height               ||
1323         s1->save_width           != s->width                ||
1324         s1->save_height          != s->height               ||
1325         av_cmp_q(s1->save_aspect, s->avctx->sample_aspect_ratio) ||
1326         (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1327         0) {
1328         if (s1->mpeg_enc_ctx_allocated) {
1329             ParseContext pc = s->parse_context;
1330             s->parse_context.buffer = 0;
1331             ff_mpv_common_end(s);
1332             s->parse_context = pc;
1333             s1->mpeg_enc_ctx_allocated = 0;
1334         }
1335
1336         ret = ff_set_dimensions(avctx, s->width, s->height);
1337         if (ret < 0)
1338             return ret;
1339
1340         if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
1341             avctx->rc_max_rate = s->bit_rate;
1342         } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
1343                    (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
1344             avctx->bit_rate = s->bit_rate;
1345         }
1346         s1->save_aspect          = s->avctx->sample_aspect_ratio;
1347         s1->save_width           = s->width;
1348         s1->save_height          = s->height;
1349         s1->save_progressive_seq = s->progressive_sequence;
1350
1351         /* low_delay may be forced, in this case we will have B-frames
1352          * that behave like P-frames. */
1353         avctx->has_b_frames = !s->low_delay;
1354
1355         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1356             // MPEG-1 fps
1357             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1358             avctx->ticks_per_frame     = 1;
1359         } else { // MPEG-2
1360             // MPEG-2 fps
1361             av_reduce(&s->avctx->framerate.num,
1362                       &s->avctx->framerate.den,
1363                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1364                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1365                       1 << 30);
1366             avctx->ticks_per_frame = 2;
1367         } // MPEG-2
1368
1369         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1370         setup_hwaccel_for_pixfmt(avctx);
1371
1372         /* Quantization matrices may need reordering
1373          * if DCT permutation is changed. */
1374         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1375
1376         ff_mpv_idct_init(s);
1377         if ((ret = ff_mpv_common_init(s)) < 0)
1378             return ret;
1379
1380         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1381         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1382         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1383         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1384
1385         s1->mpeg_enc_ctx_allocated = 1;
1386     }
1387     return 0;
1388 }
1389
1390 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1391                                 int buf_size)
1392 {
1393     Mpeg1Context *s1  = avctx->priv_data;
1394     MpegEncContext *s = &s1->mpeg_enc_ctx;
1395     int ref, f_code, vbv_delay;
1396
1397     init_get_bits(&s->gb, buf, buf_size * 8);
1398
1399     ref = get_bits(&s->gb, 10); /* temporal ref */
1400     s->pict_type = get_bits(&s->gb, 3);
1401     if (s->pict_type == 0 || s->pict_type > 3)
1402         return AVERROR_INVALIDDATA;
1403
1404     vbv_delay = get_bits(&s->gb, 16);
1405     s->vbv_delay = vbv_delay;
1406     if (s->pict_type == AV_PICTURE_TYPE_P ||
1407         s->pict_type == AV_PICTURE_TYPE_B) {
1408         s->full_pel[0] = get_bits1(&s->gb);
1409         f_code = get_bits(&s->gb, 3);
1410         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1411             return AVERROR_INVALIDDATA;
1412         f_code += !f_code;
1413         s->mpeg_f_code[0][0] = f_code;
1414         s->mpeg_f_code[0][1] = f_code;
1415     }
1416     if (s->pict_type == AV_PICTURE_TYPE_B) {
1417         s->full_pel[1] = get_bits1(&s->gb);
1418         f_code = get_bits(&s->gb, 3);
1419         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1420             return AVERROR_INVALIDDATA;
1421         f_code += !f_code;
1422         s->mpeg_f_code[1][0] = f_code;
1423         s->mpeg_f_code[1][1] = f_code;
1424     }
1425     s->current_picture.f->pict_type = s->pict_type;
1426     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1427
1428     if (avctx->debug & FF_DEBUG_PICT_INFO)
1429         av_log(avctx, AV_LOG_DEBUG,
1430                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1431
1432     s->y_dc_scale = 8;
1433     s->c_dc_scale = 8;
1434     return 0;
1435 }
1436
1437 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1438 {
1439     MpegEncContext *s = &s1->mpeg_enc_ctx;
1440     int horiz_size_ext, vert_size_ext;
1441     int bit_rate_ext;
1442
1443     skip_bits(&s->gb, 1); /* profile and level esc*/
1444     s->avctx->profile       = get_bits(&s->gb, 3);
1445     s->avctx->level         = get_bits(&s->gb, 4);
1446     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1447     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1448     horiz_size_ext          = get_bits(&s->gb, 2);
1449     vert_size_ext           = get_bits(&s->gb, 2);
1450     s->width  |= (horiz_size_ext << 12);
1451     s->height |= (vert_size_ext  << 12);
1452     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1453     s->bit_rate += (bit_rate_ext << 18) * 400;
1454     skip_bits1(&s->gb); /* marker */
1455     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1456
1457     s->low_delay = get_bits1(&s->gb);
1458     if (s->flags & CODEC_FLAG_LOW_DELAY)
1459         s->low_delay = 1;
1460
1461     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1462     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1463
1464     av_dlog(s->avctx, "sequence extension\n");
1465     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1466
1467     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1468         av_log(s->avctx, AV_LOG_DEBUG,
1469                "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%d\n",
1470                s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1471                s->avctx->rc_buffer_size, s->bit_rate);
1472 }
1473
1474 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1475 {
1476     MpegEncContext *s = &s1->mpeg_enc_ctx;
1477     int color_description, w, h;
1478
1479     skip_bits(&s->gb, 3); /* video format */
1480     color_description = get_bits1(&s->gb);
1481     if (color_description) {
1482         s->avctx->color_primaries = get_bits(&s->gb, 8);
1483         s->avctx->color_trc       = get_bits(&s->gb, 8);
1484         s->avctx->colorspace      = get_bits(&s->gb, 8);
1485     }
1486     w = get_bits(&s->gb, 14);
1487     skip_bits(&s->gb, 1); // marker
1488     h = get_bits(&s->gb, 14);
1489     // remaining 3 bits are zero padding
1490
1491     s1->pan_scan.width  = 16 * w;
1492     s1->pan_scan.height = 16 * h;
1493
1494     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1495         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1496 }
1497
1498 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1499 {
1500     MpegEncContext *s = &s1->mpeg_enc_ctx;
1501     int i, nofco;
1502
1503     nofco = 1;
1504     if (s->progressive_sequence) {
1505         if (s->repeat_first_field) {
1506             nofco++;
1507             if (s->top_field_first)
1508                 nofco++;
1509         }
1510     } else {
1511         if (s->picture_structure == PICT_FRAME) {
1512             nofco++;
1513             if (s->repeat_first_field)
1514                 nofco++;
1515         }
1516     }
1517     for (i = 0; i < nofco; i++) {
1518         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1519         skip_bits(&s->gb, 1); // marker
1520         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1521         skip_bits(&s->gb, 1); // marker
1522     }
1523
1524     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1525         av_log(s->avctx, AV_LOG_DEBUG,
1526                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1527                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1528                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1529                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1530 }
1531
1532 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1533                        uint16_t matrix1[64], int intra)
1534 {
1535     int i;
1536
1537     for (i = 0; i < 64; i++) {
1538         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1539         int v = get_bits(&s->gb, 8);
1540         if (v == 0) {
1541             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1542             return AVERROR_INVALIDDATA;
1543         }
1544         if (intra && i == 0 && v != 8) {
1545             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1546             v = 8; // needed by pink.mpg / issue1046
1547         }
1548         matrix0[j] = v;
1549         if (matrix1)
1550             matrix1[j] = v;
1551     }
1552     return 0;
1553 }
1554
1555 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1556 {
1557     av_dlog(s->avctx, "matrix extension\n");
1558
1559     if (get_bits1(&s->gb))
1560         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1561     if (get_bits1(&s->gb))
1562         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1563     if (get_bits1(&s->gb))
1564         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1565     if (get_bits1(&s->gb))
1566         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1567 }
1568
1569 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1570 {
1571     MpegEncContext *s = &s1->mpeg_enc_ctx;
1572
1573     s->full_pel[0]       = s->full_pel[1] = 0;
1574     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1575     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1576     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1577     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1578     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1579         av_log(s->avctx, AV_LOG_ERROR,
1580                "Missing picture start code, guessing missing values\n");
1581         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1582             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1583                 s->pict_type = AV_PICTURE_TYPE_I;
1584             else
1585                 s->pict_type = AV_PICTURE_TYPE_P;
1586         } else
1587             s->pict_type = AV_PICTURE_TYPE_B;
1588         s->current_picture.f->pict_type = s->pict_type;
1589         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1590     }
1591     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1592     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1593     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1594     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1595
1596     s->intra_dc_precision         = get_bits(&s->gb, 2);
1597     s->picture_structure          = get_bits(&s->gb, 2);
1598     s->top_field_first            = get_bits1(&s->gb);
1599     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1600     s->concealment_motion_vectors = get_bits1(&s->gb);
1601     s->q_scale_type               = get_bits1(&s->gb);
1602     s->intra_vlc_format           = get_bits1(&s->gb);
1603     s->alternate_scan             = get_bits1(&s->gb);
1604     s->repeat_first_field         = get_bits1(&s->gb);
1605     s->chroma_420_type            = get_bits1(&s->gb);
1606     s->progressive_frame          = get_bits1(&s->gb);
1607
1608     if (s->alternate_scan) {
1609         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1610         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1611     } else {
1612         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1613         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1614     }
1615
1616     /* composite display not parsed */
1617     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1618     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1619     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1620     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1621     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1622     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1623     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1624     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1625     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1626 }
1627
1628 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1629 {
1630     AVCodecContext *avctx = s->avctx;
1631     Mpeg1Context *s1      = (Mpeg1Context *) s;
1632     int ret;
1633
1634     /* start frame decoding */
1635     if (s->first_field || s->picture_structure == PICT_FRAME) {
1636         AVFrameSideData *pan_scan;
1637
1638         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1639             return ret;
1640
1641         ff_mpeg_er_frame_start(s);
1642
1643         /* first check if we must repeat the frame */
1644         s->current_picture_ptr->f->repeat_pict = 0;
1645         if (s->repeat_first_field) {
1646             if (s->progressive_sequence) {
1647                 if (s->top_field_first)
1648                     s->current_picture_ptr->f->repeat_pict = 4;
1649                 else
1650                     s->current_picture_ptr->f->repeat_pict = 2;
1651             } else if (s->progressive_frame) {
1652                 s->current_picture_ptr->f->repeat_pict = 1;
1653             }
1654         }
1655
1656         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1657                                           AV_FRAME_DATA_PANSCAN,
1658                                           sizeof(s1->pan_scan));
1659         if (!pan_scan)
1660             return AVERROR(ENOMEM);
1661         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1662
1663         if (s1->a53_caption) {
1664             AVFrameSideData *sd = av_frame_new_side_data(
1665                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1666                 s1->a53_caption_size);
1667             if (sd)
1668                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1669             av_freep(&s1->a53_caption);
1670         }
1671
1672         if (s1->has_stereo3d) {
1673             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1674             if (!stereo)
1675                 return AVERROR(ENOMEM);
1676
1677             *stereo = s1->stereo3d;
1678             s1->has_stereo3d = 0;
1679         }
1680
1681         if (s1->has_afd) {
1682             AVFrameSideData *sd =
1683                 av_frame_new_side_data(s->current_picture_ptr->f,
1684                                        AV_FRAME_DATA_AFD, 1);
1685             if (!sd)
1686                 return AVERROR(ENOMEM);
1687
1688             *sd->data   = s1->afd;
1689             s1->has_afd = 0;
1690         }
1691
1692         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1693             ff_thread_finish_setup(avctx);
1694     } else { // second field
1695         int i;
1696
1697         if (!s->current_picture_ptr) {
1698             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1699             return AVERROR_INVALIDDATA;
1700         }
1701
1702         if (s->avctx->hwaccel &&
1703             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1704             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1705                 av_log(avctx, AV_LOG_ERROR,
1706                        "hardware accelerator failed to decode first field\n");
1707         }
1708
1709         for (i = 0; i < 4; i++) {
1710             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1711             if (s->picture_structure == PICT_BOTTOM_FIELD)
1712                 s->current_picture.f->data[i] +=
1713                     s->current_picture_ptr->f->linesize[i];
1714         }
1715     }
1716
1717     if (avctx->hwaccel) {
1718         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1719             return ret;
1720     }
1721
1722     return 0;
1723 }
1724
1725 #define DECODE_SLICE_ERROR -1
1726 #define DECODE_SLICE_OK     0
1727
1728 /**
1729  * Decode a slice.
1730  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1731  * @return DECODE_SLICE_ERROR if the slice is damaged,
1732  *         DECODE_SLICE_OK if this slice is OK
1733  */
1734 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1735                              const uint8_t **buf, int buf_size)
1736 {
1737     AVCodecContext *avctx = s->avctx;
1738     const int lowres      = s->avctx->lowres;
1739     const int field_pic   = s->picture_structure != PICT_FRAME;
1740     int ret;
1741
1742     s->resync_mb_x =
1743     s->resync_mb_y = -1;
1744
1745     av_assert0(mb_y < s->mb_height);
1746
1747     init_get_bits(&s->gb, *buf, buf_size * 8);
1748     if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1749         skip_bits(&s->gb, 3);
1750
1751     ff_mpeg1_clean_buffers(s);
1752     s->interlaced_dct = 0;
1753
1754     s->qscale = get_qscale(s);
1755
1756     if (s->qscale == 0) {
1757         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1758         return AVERROR_INVALIDDATA;
1759     }
1760
1761     /* extra slice info */
1762     if (skip_1stop_8data_bits(&s->gb) < 0)
1763         return AVERROR_INVALIDDATA;
1764
1765     s->mb_x = 0;
1766
1767     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1768         skip_bits1(&s->gb);
1769     } else {
1770         while (get_bits_left(&s->gb) > 0) {
1771             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1772                                 MBINCR_VLC_BITS, 2);
1773             if (code < 0) {
1774                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1775                 return AVERROR_INVALIDDATA;
1776             }
1777             if (code >= 33) {
1778                 if (code == 33)
1779                     s->mb_x += 33;
1780                 /* otherwise, stuffing, nothing to do */
1781             } else {
1782                 s->mb_x += code;
1783                 break;
1784             }
1785         }
1786     }
1787
1788     if (s->mb_x >= (unsigned) s->mb_width) {
1789         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1790         return AVERROR_INVALIDDATA;
1791     }
1792
1793     if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1794         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1795         int start_code = -1;
1796         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1797         if (buf_end < *buf + buf_size)
1798             buf_end -= 4;
1799         s->mb_y = mb_y;
1800         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1801             return DECODE_SLICE_ERROR;
1802         *buf = buf_end;
1803         return DECODE_SLICE_OK;
1804     }
1805
1806     s->resync_mb_x = s->mb_x;
1807     s->resync_mb_y = s->mb_y = mb_y;
1808     s->mb_skip_run = 0;
1809     ff_init_block_index(s);
1810
1811     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1812         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1813             av_log(s->avctx, AV_LOG_DEBUG,
1814                    "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",
1815                    s->qscale,
1816                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1817                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1818                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1819                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1820                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1821                    s->progressive_sequence ? "ps"  : "",
1822                    s->progressive_frame    ? "pf"  : "",
1823                    s->alternate_scan       ? "alt" : "",
1824                    s->top_field_first      ? "top" : "",
1825                    s->intra_dc_precision, s->picture_structure,
1826                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1827                    s->q_scale_type, s->intra_vlc_format,
1828                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1829         }
1830     }
1831
1832     for (;;) {
1833         // If 1, we memcpy blocks in xvmcvideo.
1834         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1835             ff_xvmc_init_block(s); // set s->block
1836
1837         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1838             return ret;
1839
1840         // Note motion_val is normally NULL unless we want to extract the MVs.
1841         if (s->current_picture.motion_val[0] && !s->encoding) {
1842             const int wrap = s->b8_stride;
1843             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1844             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1845             int motion_x, motion_y, dir, i;
1846
1847             for (i = 0; i < 2; i++) {
1848                 for (dir = 0; dir < 2; dir++) {
1849                     if (s->mb_intra ||
1850                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1851                         motion_x = motion_y = 0;
1852                     } else if (s->mv_type == MV_TYPE_16X16 ||
1853                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1854                         motion_x = s->mv[dir][0][0];
1855                         motion_y = s->mv[dir][0][1];
1856                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1857                         motion_x = s->mv[dir][i][0];
1858                         motion_y = s->mv[dir][i][1];
1859                     }
1860
1861                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1862                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1863                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1864                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1865                     s->current_picture.ref_index [dir][b8_xy]     =
1866                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1867                     av_assert2(s->field_select[dir][i] == 0 ||
1868                                s->field_select[dir][i] == 1);
1869                 }
1870                 xy    += wrap;
1871                 b8_xy += 2;
1872             }
1873         }
1874
1875         s->dest[0] += 16 >> lowres;
1876         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1877         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1878
1879         ff_mpv_decode_mb(s, s->block);
1880
1881         if (++s->mb_x >= s->mb_width) {
1882             const int mb_size = 16 >> s->avctx->lowres;
1883
1884             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1885             ff_mpv_report_decode_progress(s);
1886
1887             s->mb_x  = 0;
1888             s->mb_y += 1 << field_pic;
1889
1890             if (s->mb_y >= s->mb_height) {
1891                 int left   = get_bits_left(&s->gb);
1892                 int is_d10 = s->chroma_format == 2 &&
1893                              s->pict_type == AV_PICTURE_TYPE_I &&
1894                              avctx->profile == 0 && avctx->level == 5 &&
1895                              s->intra_dc_precision == 2 &&
1896                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1897                              s->progressive_frame == 0
1898                              /* vbv_delay == 0xBBB || 0xE10 */;
1899
1900                 if (left >= 32 && !is_d10) {
1901                     GetBitContext gb = s->gb;
1902                     align_get_bits(&gb);
1903                     if (show_bits(&gb, 24) == 0x060E2B) {
1904                         av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
1905                         is_d10 = 1;
1906                     }
1907                 }
1908
1909                 if (left < 0 ||
1910                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1911                     ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1912                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1913                            left, show_bits(&s->gb, FFMIN(left, 23)));
1914                     return AVERROR_INVALIDDATA;
1915                 } else
1916                     goto eos;
1917             }
1918             // There are some files out there which are missing the last slice
1919             // in cases where the slice is completely outside the visible
1920             // area, we detect this here instead of running into the end expecting
1921             // more data
1922             if (s->mb_y >= ((s->height + 15) >> 4) &&
1923                 s->progressive_frame &&
1924                 !s->progressive_sequence &&
1925                 get_bits_left(&s->gb) <= 8 &&
1926                 get_bits_left(&s->gb) >= 0 &&
1927                 s->mb_skip_run == -1 &&
1928                 show_bits(&s->gb, 8) == 0)
1929                 goto eos;
1930
1931             ff_init_block_index(s);
1932         }
1933
1934         /* skip mb handling */
1935         if (s->mb_skip_run == -1) {
1936             /* read increment again */
1937             s->mb_skip_run = 0;
1938             for (;;) {
1939                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1940                                     MBINCR_VLC_BITS, 2);
1941                 if (code < 0) {
1942                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1943                     return AVERROR_INVALIDDATA;
1944                 }
1945                 if (code >= 33) {
1946                     if (code == 33) {
1947                         s->mb_skip_run += 33;
1948                     } else if (code == 35) {
1949                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1950                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1951                             return AVERROR_INVALIDDATA;
1952                         }
1953                         goto eos; /* end of slice */
1954                     }
1955                     /* otherwise, stuffing, nothing to do */
1956                 } else {
1957                     s->mb_skip_run += code;
1958                     break;
1959                 }
1960             }
1961             if (s->mb_skip_run) {
1962                 int i;
1963                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1964                     av_log(s->avctx, AV_LOG_ERROR,
1965                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1966                     return AVERROR_INVALIDDATA;
1967                 }
1968
1969                 /* skip mb */
1970                 s->mb_intra = 0;
1971                 for (i = 0; i < 12; i++)
1972                     s->block_last_index[i] = -1;
1973                 if (s->picture_structure == PICT_FRAME)
1974                     s->mv_type = MV_TYPE_16X16;
1975                 else
1976                     s->mv_type = MV_TYPE_FIELD;
1977                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1978                     /* if P type, zero motion vector is implied */
1979                     s->mv_dir             = MV_DIR_FORWARD;
1980                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1981                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1982                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1983                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1984                 } else {
1985                     /* if B type, reuse previous vectors and directions */
1986                     s->mv[0][0][0] = s->last_mv[0][0][0];
1987                     s->mv[0][0][1] = s->last_mv[0][0][1];
1988                     s->mv[1][0][0] = s->last_mv[1][0][0];
1989                     s->mv[1][0][1] = s->last_mv[1][0][1];
1990                 }
1991             }
1992         }
1993     }
1994 eos: // end of slice
1995     if (get_bits_left(&s->gb) < 0) {
1996         av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
1997         return AVERROR_INVALIDDATA;
1998     }
1999     *buf += (get_bits_count(&s->gb) - 1) / 8;
2000     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
2001     return 0;
2002 }
2003
2004 static int slice_decode_thread(AVCodecContext *c, void *arg)
2005 {
2006     MpegEncContext *s   = *(void **) arg;
2007     const uint8_t *buf  = s->gb.buffer;
2008     int mb_y            = s->start_mb_y;
2009     const int field_pic = s->picture_structure != PICT_FRAME;
2010
2011     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
2012
2013     for (;;) {
2014         uint32_t start_code;
2015         int ret;
2016
2017         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
2018         emms_c();
2019         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2020                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
2021                 s->start_mb_y, s->end_mb_y, s->er.error_count);
2022         if (ret < 0) {
2023             if (c->err_recognition & AV_EF_EXPLODE)
2024                 return ret;
2025             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
2026                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2027                                 s->mb_x, s->mb_y,
2028                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2029         } else {
2030             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2031                             s->mb_x - 1, s->mb_y,
2032                             ER_AC_END | ER_DC_END | ER_MV_END);
2033         }
2034
2035         if (s->mb_y == s->end_mb_y)
2036             return 0;
2037
2038         start_code = -1;
2039         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2040         mb_y       = start_code - SLICE_MIN_START_CODE;
2041         if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2042             mb_y += (*buf&0xE0)<<2;
2043         mb_y <<= field_pic;
2044         if (s->picture_structure == PICT_BOTTOM_FIELD)
2045             mb_y++;
2046         if (mb_y < 0 || mb_y >= s->end_mb_y)
2047             return AVERROR_INVALIDDATA;
2048     }
2049 }
2050
2051 /**
2052  * Handle slice ends.
2053  * @return 1 if it seems to be the last slice
2054  */
2055 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2056 {
2057     Mpeg1Context *s1  = avctx->priv_data;
2058     MpegEncContext *s = &s1->mpeg_enc_ctx;
2059
2060     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2061         return 0;
2062
2063     if (s->avctx->hwaccel) {
2064         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
2065             av_log(avctx, AV_LOG_ERROR,
2066                    "hardware accelerator failed to decode picture\n");
2067     }
2068
2069     /* end of slice reached */
2070     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
2071         /* end of image */
2072
2073         ff_er_frame_end(&s->er);
2074
2075         ff_mpv_frame_end(s);
2076
2077         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2078             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2079             if (ret < 0)
2080                 return ret;
2081             ff_print_debug_info(s, s->current_picture_ptr, pict);
2082             ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2083         } else {
2084             if (avctx->active_thread_type & FF_THREAD_FRAME)
2085                 s->picture_number++;
2086             /* latency of 1 frame for I- and P-frames */
2087             /* XXX: use another variable than picture_number */
2088             if (s->last_picture_ptr) {
2089                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2090                 if (ret < 0)
2091                     return ret;
2092                 ff_print_debug_info(s, s->last_picture_ptr, pict);
2093                 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2094             }
2095         }
2096
2097         return 1;
2098     } else {
2099         return 0;
2100     }
2101 }
2102
2103 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2104                                  const uint8_t *buf, int buf_size)
2105 {
2106     Mpeg1Context *s1  = avctx->priv_data;
2107     MpegEncContext *s = &s1->mpeg_enc_ctx;
2108     int width, height;
2109     int i, v, j;
2110
2111     init_get_bits(&s->gb, buf, buf_size * 8);
2112
2113     width  = get_bits(&s->gb, 12);
2114     height = get_bits(&s->gb, 12);
2115     if (width == 0 || height == 0) {
2116         av_log(avctx, AV_LOG_WARNING,
2117                "Invalid horizontal or vertical size value.\n");
2118         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2119             return AVERROR_INVALIDDATA;
2120     }
2121     s->aspect_ratio_info = get_bits(&s->gb, 4);
2122     if (s->aspect_ratio_info == 0) {
2123         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2124         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2125             return AVERROR_INVALIDDATA;
2126     }
2127     s->frame_rate_index = get_bits(&s->gb, 4);
2128     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2129         av_log(avctx, AV_LOG_WARNING,
2130                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2131         s->frame_rate_index = 1;
2132     }
2133     s->bit_rate = get_bits(&s->gb, 18) * 400;
2134     if (get_bits1(&s->gb) == 0) { /* marker */
2135         av_log(avctx, AV_LOG_ERROR, "Marker in sequence header missing\n");
2136         return AVERROR_INVALIDDATA;
2137     }
2138     s->width  = width;
2139     s->height = height;
2140
2141     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2142     skip_bits(&s->gb, 1);
2143
2144     /* get matrix */
2145     if (get_bits1(&s->gb)) {
2146         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2147     } else {
2148         for (i = 0; i < 64; i++) {
2149             j = s->idsp.idct_permutation[i];
2150             v = ff_mpeg1_default_intra_matrix[i];
2151             s->intra_matrix[j]        = v;
2152             s->chroma_intra_matrix[j] = v;
2153         }
2154     }
2155     if (get_bits1(&s->gb)) {
2156         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2157     } else {
2158         for (i = 0; i < 64; i++) {
2159             int j = s->idsp.idct_permutation[i];
2160             v = ff_mpeg1_default_non_intra_matrix[i];
2161             s->inter_matrix[j]        = v;
2162             s->chroma_inter_matrix[j] = v;
2163         }
2164     }
2165
2166     if (show_bits(&s->gb, 23) != 0) {
2167         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2168         return AVERROR_INVALIDDATA;
2169     }
2170
2171     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2172     s->progressive_sequence = 1;
2173     s->progressive_frame    = 1;
2174     s->picture_structure    = PICT_FRAME;
2175     s->first_field          = 0;
2176     s->frame_pred_frame_dct = 1;
2177     s->chroma_format        = 1;
2178     s->codec_id             =
2179     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2180     s->out_format           = FMT_MPEG1;
2181     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2182     if (s->flags & CODEC_FLAG_LOW_DELAY)
2183         s->low_delay = 1;
2184
2185     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2186         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d, aspect_ratio_info: %d \n",
2187                s->avctx->rc_buffer_size, s->bit_rate, s->aspect_ratio_info);
2188
2189     return 0;
2190 }
2191
2192 static int vcr2_init_sequence(AVCodecContext *avctx)
2193 {
2194     Mpeg1Context *s1  = avctx->priv_data;
2195     MpegEncContext *s = &s1->mpeg_enc_ctx;
2196     int i, v, ret;
2197
2198     /* start new MPEG-1 context decoding */
2199     s->out_format = FMT_MPEG1;
2200     if (s1->mpeg_enc_ctx_allocated) {
2201         ff_mpv_common_end(s);
2202         s1->mpeg_enc_ctx_allocated = 0;
2203     }
2204     s->width            = avctx->coded_width;
2205     s->height           = avctx->coded_height;
2206     avctx->has_b_frames = 0; // true?
2207     s->low_delay        = 1;
2208
2209     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2210     setup_hwaccel_for_pixfmt(avctx);
2211
2212     ff_mpv_idct_init(s);
2213     if ((ret = ff_mpv_common_init(s)) < 0)
2214         return ret;
2215     s1->mpeg_enc_ctx_allocated = 1;
2216
2217     for (i = 0; i < 64; i++) {
2218         int j = s->idsp.idct_permutation[i];
2219         v = ff_mpeg1_default_intra_matrix[i];
2220         s->intra_matrix[j]        = v;
2221         s->chroma_intra_matrix[j] = v;
2222
2223         v = ff_mpeg1_default_non_intra_matrix[i];
2224         s->inter_matrix[j]        = v;
2225         s->chroma_inter_matrix[j] = v;
2226     }
2227
2228     s->progressive_sequence  = 1;
2229     s->progressive_frame     = 1;
2230     s->picture_structure     = PICT_FRAME;
2231     s->first_field           = 0;
2232     s->frame_pred_frame_dct  = 1;
2233     s->chroma_format         = 1;
2234     if (s->codec_tag == AV_RL32("BW10")) {
2235         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2236     } else {
2237         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2238         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2239     }
2240     s1->save_width           = s->width;
2241     s1->save_height          = s->height;
2242     s1->save_progressive_seq = s->progressive_sequence;
2243     return 0;
2244 }
2245
2246 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2247                               const uint8_t *p, int buf_size)
2248 {
2249     Mpeg1Context *s1 = avctx->priv_data;
2250
2251     if (buf_size >= 6 &&
2252         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2253         p[4] == 3 && (p[5] & 0x40)) {
2254         /* extract A53 Part 4 CC data */
2255         int cc_count = p[5] & 0x1f;
2256         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2257             av_freep(&s1->a53_caption);
2258             s1->a53_caption_size = cc_count * 3;
2259             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2260             if (s1->a53_caption)
2261                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2262         }
2263         return 1;
2264     } else if (buf_size >= 11 &&
2265                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2266         /* extract DVD CC data */
2267         int cc_count = 0;
2268         int i;
2269         // There is a caption count field in the data, but it is often
2270         // incorect.  So count the number of captions present.
2271         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2272             cc_count++;
2273         // Transform the DVD format into A53 Part 4 format
2274         if (cc_count > 0) {
2275             av_freep(&s1->a53_caption);
2276             s1->a53_caption_size = cc_count * 6;
2277             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2278             if (s1->a53_caption) {
2279                 uint8_t field1 = !!(p[4] & 0x80);
2280                 uint8_t *cap = s1->a53_caption;
2281                 p += 5;
2282                 for (i = 0; i < cc_count; i++) {
2283                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2284                     cap[1] = p[1];
2285                     cap[2] = p[2];
2286                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2287                     cap[4] = p[4];
2288                     cap[5] = p[5];
2289                     cap += 6;
2290                     p += 6;
2291                 }
2292             }
2293         }
2294         return 1;
2295     }
2296     return 0;
2297 }
2298
2299 static void mpeg_decode_user_data(AVCodecContext *avctx,
2300                                   const uint8_t *p, int buf_size)
2301 {
2302     Mpeg1Context *s = avctx->priv_data;
2303     const uint8_t *buf_end = p + buf_size;
2304     Mpeg1Context *s1 = avctx->priv_data;
2305
2306 #if 0
2307     int i;
2308     for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2309         av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
2310     }
2311     av_log(avctx, AV_LOG_ERROR, "\n");
2312 #endif
2313
2314     if (buf_size > 29){
2315         int i;
2316         for(i=0; i<20; i++)
2317             if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2318                 s->tmpgexs= 1;
2319             }
2320     }
2321     /* we parse the DTG active format information */
2322     if (buf_end - p >= 5 &&
2323         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2324         int flags = p[4];
2325         p += 5;
2326         if (flags & 0x80) {
2327             /* skip event id */
2328             p += 2;
2329         }
2330         if (flags & 0x40) {
2331             if (buf_end - p < 1)
2332                 return;
2333 #if FF_API_AFD
2334 FF_DISABLE_DEPRECATION_WARNINGS
2335             avctx->dtg_active_format = p[0] & 0x0f;
2336 FF_ENABLE_DEPRECATION_WARNINGS
2337 #endif /* FF_API_AFD */
2338             s1->has_afd = 1;
2339             s1->afd     = p[0] & 0x0f;
2340         }
2341     } else if (buf_end - p >= 6 &&
2342                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2343                p[4] == 0x03) { // S3D_video_format_length
2344         // the 0x7F mask ignores the reserved_bit value
2345         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2346
2347         if (S3D_video_format_type == 0x03 ||
2348             S3D_video_format_type == 0x04 ||
2349             S3D_video_format_type == 0x08 ||
2350             S3D_video_format_type == 0x23) {
2351
2352             s1->has_stereo3d = 1;
2353
2354             switch (S3D_video_format_type) {
2355             case 0x03:
2356                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2357                 break;
2358             case 0x04:
2359                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2360                 break;
2361             case 0x08:
2362                 s1->stereo3d.type = AV_STEREO3D_2D;
2363                 break;
2364             case 0x23:
2365                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2366                 break;
2367             }
2368         }
2369     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2370         return;
2371     }
2372 }
2373
2374 static void mpeg_decode_gop(AVCodecContext *avctx,
2375                             const uint8_t *buf, int buf_size)
2376 {
2377     Mpeg1Context *s1  = avctx->priv_data;
2378     MpegEncContext *s = &s1->mpeg_enc_ctx;
2379     int broken_link;
2380     int64_t tc;
2381
2382     init_get_bits(&s->gb, buf, buf_size * 8);
2383
2384     tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2385
2386     s->closed_gop = get_bits1(&s->gb);
2387     /* broken_link indicate that after editing the
2388      * reference frames of the first B-Frames after GOP I-Frame
2389      * are missing (open gop) */
2390     broken_link = get_bits1(&s->gb);
2391
2392     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2393         char tcbuf[AV_TIMECODE_STR_SIZE];
2394         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2395         av_log(s->avctx, AV_LOG_DEBUG,
2396                "GOP (%s) closed_gop=%d broken_link=%d\n",
2397                tcbuf, s->closed_gop, broken_link);
2398     }
2399 }
2400
2401 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2402                          int *got_output, const uint8_t *buf, int buf_size)
2403 {
2404     Mpeg1Context *s = avctx->priv_data;
2405     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2406     const uint8_t *buf_ptr = buf;
2407     const uint8_t *buf_end = buf + buf_size;
2408     int ret, input_size;
2409     int last_code = 0, skip_frame = 0;
2410     int picture_start_code_seen = 0;
2411
2412     for (;;) {
2413         /* find next start code */
2414         uint32_t start_code = -1;
2415         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2416         if (start_code > 0x1ff) {
2417             if (!skip_frame) {
2418                 if (HAVE_THREADS &&
2419                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2420                     !avctx->hwaccel) {
2421                     int i;
2422                     av_assert0(avctx->thread_count > 1);
2423
2424                     avctx->execute(avctx, slice_decode_thread,
2425                                    &s2->thread_context[0], NULL,
2426                                    s->slice_count, sizeof(void *));
2427                     for (i = 0; i < s->slice_count; i++)
2428                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2429                 }
2430
2431                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2432                     && uses_vdpau(avctx))
2433                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2434
2435                 ret = slice_end(avctx, picture);
2436                 if (ret < 0)
2437                     return ret;
2438                 else if (ret) {
2439                     // FIXME: merge with the stuff in mpeg_decode_slice
2440                     if (s2->last_picture_ptr || s2->low_delay)
2441                         *got_output = 1;
2442                 }
2443             }
2444             s2->pict_type = 0;
2445
2446             if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
2447                 return AVERROR_INVALIDDATA;
2448
2449             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2450         }
2451
2452         input_size = buf_end - buf_ptr;
2453
2454         if (avctx->debug & FF_DEBUG_STARTCODE)
2455             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2456                    start_code, buf_ptr - buf, input_size);
2457
2458         /* prepare data for next start code */
2459         switch (start_code) {
2460         case SEQ_START_CODE:
2461             if (last_code == 0) {
2462                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2463                 if (buf != avctx->extradata)
2464                     s->sync = 1;
2465             } else {
2466                 av_log(avctx, AV_LOG_ERROR,
2467                        "ignoring SEQ_START_CODE after %X\n", last_code);
2468                 if (avctx->err_recognition & AV_EF_EXPLODE)
2469                     return AVERROR_INVALIDDATA;
2470             }
2471             break;
2472
2473         case PICTURE_START_CODE:
2474             if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
2475                /* If it's a frame picture, there can't be more than one picture header.
2476                   Yet, it does happen and we need to handle it. */
2477                av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
2478                break;
2479             }
2480             picture_start_code_seen = 1;
2481
2482             if (s2->width <= 0 || s2->height <= 0) {
2483                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2484                        s2->width, s2->height);
2485                 return AVERROR_INVALIDDATA;
2486             }
2487
2488             if (s->tmpgexs){
2489                 s2->intra_dc_precision= 3;
2490                 s2->intra_matrix[0]= 1;
2491             }
2492             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2493                 !avctx->hwaccel && s->slice_count) {
2494                 int i;
2495
2496                 avctx->execute(avctx, slice_decode_thread,
2497                                s2->thread_context, NULL,
2498                                s->slice_count, sizeof(void *));
2499                 for (i = 0; i < s->slice_count; i++)
2500                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2501                 s->slice_count = 0;
2502             }
2503             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2504                 ret = mpeg_decode_postinit(avctx);
2505                 if (ret < 0) {
2506                     av_log(avctx, AV_LOG_ERROR,
2507                            "mpeg_decode_postinit() failure\n");
2508                     return ret;
2509                 }
2510
2511                 /* We have a complete image: we try to decompress it. */
2512                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2513                     s2->pict_type = 0;
2514                 s->first_slice = 1;
2515                 last_code      = PICTURE_START_CODE;
2516             } else {
2517                 av_log(avctx, AV_LOG_ERROR,
2518                        "ignoring pic after %X\n", last_code);
2519                 if (avctx->err_recognition & AV_EF_EXPLODE)
2520                     return AVERROR_INVALIDDATA;
2521             }
2522             break;
2523         case EXT_START_CODE:
2524             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2525
2526             switch (get_bits(&s2->gb, 4)) {
2527             case 0x1:
2528                 if (last_code == 0) {
2529                     mpeg_decode_sequence_extension(s);
2530                 } else {
2531                     av_log(avctx, AV_LOG_ERROR,
2532                            "ignoring seq ext after %X\n", last_code);
2533                     if (avctx->err_recognition & AV_EF_EXPLODE)
2534                         return AVERROR_INVALIDDATA;
2535                 }
2536                 break;
2537             case 0x2:
2538                 mpeg_decode_sequence_display_extension(s);
2539                 break;
2540             case 0x3:
2541                 mpeg_decode_quant_matrix_extension(s2);
2542                 break;
2543             case 0x7:
2544                 mpeg_decode_picture_display_extension(s);
2545                 break;
2546             case 0x8:
2547                 if (last_code == PICTURE_START_CODE) {
2548                     mpeg_decode_picture_coding_extension(s);
2549                 } else {
2550                     av_log(avctx, AV_LOG_ERROR,
2551                            "ignoring pic cod ext after %X\n", last_code);
2552                     if (avctx->err_recognition & AV_EF_EXPLODE)
2553                         return AVERROR_INVALIDDATA;
2554                 }
2555                 break;
2556             }
2557             break;
2558         case USER_START_CODE:
2559             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2560             break;
2561         case GOP_START_CODE:
2562             if (last_code == 0) {
2563                 s2->first_field = 0;
2564                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2565                 s->sync = 1;
2566             } else {
2567                 av_log(avctx, AV_LOG_ERROR,
2568                        "ignoring GOP_START_CODE after %X\n", last_code);
2569                 if (avctx->err_recognition & AV_EF_EXPLODE)
2570                     return AVERROR_INVALIDDATA;
2571             }
2572             break;
2573         default:
2574             if (start_code >= SLICE_MIN_START_CODE &&
2575                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2576                 if (s2->progressive_sequence && !s2->progressive_frame) {
2577                     s2->progressive_frame = 1;
2578                     av_log(s2->avctx, AV_LOG_ERROR,
2579                            "interlaced frame in progressive sequence, ignoring\n");
2580                 }
2581
2582                 if (s2->picture_structure == 0 ||
2583                     (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2584                     av_log(s2->avctx, AV_LOG_ERROR,
2585                            "picture_structure %d invalid, ignoring\n",
2586                            s2->picture_structure);
2587                     s2->picture_structure = PICT_FRAME;
2588                 }
2589
2590                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2591                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2592
2593                 if (s2->picture_structure == PICT_FRAME) {
2594                     s2->first_field = 0;
2595                     s2->v_edge_pos  = 16 * s2->mb_height;
2596                 } else {
2597                     s2->first_field ^= 1;
2598                     s2->v_edge_pos   = 8 * s2->mb_height;
2599                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2600                 }
2601             }
2602             if (start_code >= SLICE_MIN_START_CODE &&
2603                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2604                 const int field_pic = s2->picture_structure != PICT_FRAME;
2605                 int mb_y = start_code - SLICE_MIN_START_CODE;
2606                 last_code = SLICE_MIN_START_CODE;
2607                 if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2608                     mb_y += (*buf_ptr&0xE0)<<2;
2609
2610                 mb_y <<= field_pic;
2611                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2612                     mb_y++;
2613
2614                 if (buf_end - buf_ptr < 2) {
2615                     av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
2616                     return AVERROR_INVALIDDATA;
2617                 }
2618
2619                 if (mb_y >= s2->mb_height) {
2620                     av_log(s2->avctx, AV_LOG_ERROR,
2621                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2622                     return AVERROR_INVALIDDATA;
2623                 }
2624
2625                 if (!s2->last_picture_ptr) {
2626                     /* Skip B-frames if we do not have reference frames and
2627                      * GOP is not closed. */
2628                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2629                         if (!s2->closed_gop) {
2630                             skip_frame = 1;
2631                             break;
2632                         }
2633                     }
2634                 }
2635                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->flags2 & CODEC_FLAG2_SHOW_ALL))
2636                     s->sync = 1;
2637                 if (!s2->next_picture_ptr) {
2638                     /* Skip P-frames if we do not have a reference frame or
2639                      * we have an invalid header. */
2640                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2641                         skip_frame = 1;
2642                         break;
2643                     }
2644                 }
2645                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2646                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2647                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2648                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2649                     avctx->skip_frame >= AVDISCARD_ALL) {
2650                     skip_frame = 1;
2651                     break;
2652                 }
2653
2654                 if (!s->mpeg_enc_ctx_allocated)
2655                     break;
2656
2657                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2658                     if (mb_y < avctx->skip_top ||
2659                         mb_y >= s2->mb_height - avctx->skip_bottom)
2660                         break;
2661                 }
2662
2663                 if (!s2->pict_type) {
2664                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2665                     if (avctx->err_recognition & AV_EF_EXPLODE)
2666                         return AVERROR_INVALIDDATA;
2667                     break;
2668                 }
2669
2670                 if (s->first_slice) {
2671                     skip_frame     = 0;
2672                     s->first_slice = 0;
2673                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2674                         return ret;
2675                 }
2676                 if (!s2->current_picture_ptr) {
2677                     av_log(avctx, AV_LOG_ERROR,
2678                            "current_picture not initialized\n");
2679                     return AVERROR_INVALIDDATA;
2680                 }
2681
2682                 if (uses_vdpau(avctx)) {
2683                     s->slice_count++;
2684                     break;
2685                 }
2686
2687                 if (HAVE_THREADS &&
2688                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2689                     !avctx->hwaccel) {
2690                     int threshold = (s2->mb_height * s->slice_count +
2691                                      s2->slice_context_count / 2) /
2692                                     s2->slice_context_count;
2693                     av_assert0(avctx->thread_count > 1);
2694                     if (threshold <= mb_y) {
2695                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2696
2697                         thread_context->start_mb_y = mb_y;
2698                         thread_context->end_mb_y   = s2->mb_height;
2699                         if (s->slice_count) {
2700                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2701                             ret = ff_update_duplicate_context(thread_context, s2);
2702                             if (ret < 0)
2703                                 return ret;
2704                         }
2705                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2706                         s->slice_count++;
2707                     }
2708                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2709                 } else {
2710                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2711                     emms_c();
2712
2713                     if (ret < 0) {
2714                         if (avctx->err_recognition & AV_EF_EXPLODE)
2715                             return ret;
2716                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2717                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2718                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2719                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2720                     } else {
2721                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2722                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2723                                         ER_AC_END | ER_DC_END | ER_MV_END);
2724                     }
2725                 }
2726             }
2727             break;
2728         }
2729     }
2730 }
2731
2732 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2733                              int *got_output, AVPacket *avpkt)
2734 {
2735     const uint8_t *buf = avpkt->data;
2736     int ret;
2737     int buf_size = avpkt->size;
2738     Mpeg1Context *s = avctx->priv_data;
2739     AVFrame *picture = data;
2740     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2741
2742     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2743         /* special case for last picture */
2744         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2745             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2746             if (ret < 0)
2747                 return ret;
2748
2749             s2->next_picture_ptr = NULL;
2750
2751             *got_output = 1;
2752         }
2753         return buf_size;
2754     }
2755
2756     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2757         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2758                                            buf_size, NULL);
2759
2760         if (ff_combine_frame(&s2->parse_context, next,
2761                              (const uint8_t **) &buf, &buf_size) < 0)
2762             return buf_size;
2763     }
2764
2765     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2766     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2767                                            || s2->codec_tag == AV_RL32("BW10")
2768                                           ))
2769         vcr2_init_sequence(avctx);
2770
2771     s->slice_count = 0;
2772
2773     if (avctx->extradata && !s->extradata_decoded) {
2774         ret = decode_chunks(avctx, picture, got_output,
2775                             avctx->extradata, avctx->extradata_size);
2776         if (*got_output) {
2777             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2778             *got_output = 0;
2779         }
2780         s->extradata_decoded = 1;
2781         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
2782             s2->current_picture_ptr = NULL;
2783             return ret;
2784         }
2785     }
2786
2787     ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
2788     if (ret<0 || *got_output)
2789         s2->current_picture_ptr = NULL;
2790
2791     return ret;
2792 }
2793
2794 static void flush(AVCodecContext *avctx)
2795 {
2796     Mpeg1Context *s = avctx->priv_data;
2797
2798     s->sync       = 0;
2799
2800     ff_mpeg_flush(avctx);
2801 }
2802
2803 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2804 {
2805     Mpeg1Context *s = avctx->priv_data;
2806
2807     if (s->mpeg_enc_ctx_allocated)
2808         ff_mpv_common_end(&s->mpeg_enc_ctx);
2809     av_freep(&s->a53_caption);
2810     return 0;
2811 }
2812
2813 static const AVProfile mpeg2_video_profiles[] = {
2814     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2815     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2816     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2817     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2818     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2819     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2820     { FF_PROFILE_RESERVED,           "Reserved"           },
2821     { FF_PROFILE_RESERVED,           "Reserved"           },
2822     { FF_PROFILE_UNKNOWN                                  },
2823 };
2824
2825 AVCodec ff_mpeg1video_decoder = {
2826     .name                  = "mpeg1video",
2827     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2828     .type                  = AVMEDIA_TYPE_VIDEO,
2829     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2830     .priv_data_size        = sizeof(Mpeg1Context),
2831     .init                  = mpeg_decode_init,
2832     .close                 = mpeg_decode_end,
2833     .decode                = mpeg_decode_frame,
2834     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2835                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2836                              CODEC_CAP_SLICE_THREADS,
2837     .flush                 = flush,
2838     .max_lowres            = 3,
2839     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2840 };
2841
2842 AVCodec ff_mpeg2video_decoder = {
2843     .name           = "mpeg2video",
2844     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2845     .type           = AVMEDIA_TYPE_VIDEO,
2846     .id             = AV_CODEC_ID_MPEG2VIDEO,
2847     .priv_data_size = sizeof(Mpeg1Context),
2848     .init           = mpeg_decode_init,
2849     .close          = mpeg_decode_end,
2850     .decode         = mpeg_decode_frame,
2851     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2852                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2853                       CODEC_CAP_SLICE_THREADS,
2854     .flush          = flush,
2855     .max_lowres     = 3,
2856     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2857 };
2858
2859 //legacy decoder
2860 AVCodec ff_mpegvideo_decoder = {
2861     .name           = "mpegvideo",
2862     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2863     .type           = AVMEDIA_TYPE_VIDEO,
2864     .id             = AV_CODEC_ID_MPEG2VIDEO,
2865     .priv_data_size = sizeof(Mpeg1Context),
2866     .init           = mpeg_decode_init,
2867     .close          = mpeg_decode_end,
2868     .decode         = mpeg_decode_frame,
2869     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
2870     .flush          = flush,
2871     .max_lowres     = 3,
2872 };
2873
2874 #if FF_API_XVMC
2875 #if CONFIG_MPEG_XVMC_DECODER
2876 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2877 {
2878     if (avctx->active_thread_type & FF_THREAD_SLICE)
2879         return -1;
2880     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2881         return -1;
2882     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2883         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2884     }
2885     mpeg_decode_init(avctx);
2886
2887     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2888     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2889
2890     return 0;
2891 }
2892
2893 AVCodec ff_mpeg_xvmc_decoder = {
2894     .name           = "mpegvideo_xvmc",
2895     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2896     .type           = AVMEDIA_TYPE_VIDEO,
2897     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2898     .priv_data_size = sizeof(Mpeg1Context),
2899     .init           = mpeg_mc_decode_init,
2900     .close          = mpeg_decode_end,
2901     .decode         = mpeg_decode_frame,
2902     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2903                       CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2904     .flush          = flush,
2905 };
2906
2907 #endif
2908 #endif /* FF_API_XVMC */
2909
2910 #if CONFIG_MPEG_VDPAU_DECODER
2911 AVCodec ff_mpeg_vdpau_decoder = {
2912     .name           = "mpegvideo_vdpau",
2913     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2914     .type           = AVMEDIA_TYPE_VIDEO,
2915     .id             = AV_CODEC_ID_MPEG2VIDEO,
2916     .priv_data_size = sizeof(Mpeg1Context),
2917     .init           = mpeg_decode_init,
2918     .close          = mpeg_decode_end,
2919     .decode         = mpeg_decode_frame,
2920     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2921                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2922     .flush          = flush,
2923 };
2924 #endif
2925
2926 #if CONFIG_MPEG1_VDPAU_DECODER
2927 AVCodec ff_mpeg1_vdpau_decoder = {
2928     .name           = "mpeg1video_vdpau",
2929     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2930     .type           = AVMEDIA_TYPE_VIDEO,
2931     .id             = AV_CODEC_ID_MPEG1VIDEO,
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