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   1 /*
   2  * MPEG-1/2 decoder
   3  * Copyright (c) 2000, 2001 Fabrice Bellard
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav 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  * Libav 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 Libav; 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 DEBUG
  29 #include "libavutil/attributes.h"
  30 #include "libavutil/internal.h"
  31 #include "internal.h"
  32 #include "avcodec.h"
  33 #include "dsputil.h"
  34 #include "mpegvideo.h"
  35 #include "error_resilience.h"
  36 #include "mpeg12.h"
  37 #include "mpeg12data.h"
  38 #include "mpeg12decdata.h"
  39 #include "bytestream.h"
  40 #include "vdpau_internal.h"
  41 #include "xvmc_internal.h"
  42 #include "thread.h"
  43
  44 //#undef NDEBUG
  45 //#include <assert.h>
  46
  47 typedef struct Mpeg1Context {
  48     MpegEncContext mpeg_enc_ctx;
  49     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
  50     int repeat_field; /* true if we must repeat the field */
  51     AVPanScan pan_scan;              /**< some temporary storage for the panscan */
  52     int slice_count;
  53     int swap_uv;//indicate VCR2
  54     int save_aspect_info;
  55     int save_width, save_height, save_progressive_seq;
  56     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
  57     int sync;                        ///< Did we reach a sync point like a GOP/SEQ/KEYFrame?
  58     int closed_gop;                  ///< GOP is closed
  59     int extradata_decoded;
  60 } Mpeg1Context;
  61
  62 /* as H.263, but only 17 codes */
  63 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
  64 {
  65     int code, sign, val, shift;
  66
  67     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
  68     if (code == 0) {
  69         return pred;
  70     }
  71     if (code < 0) {
  72         return 0xffff;
  73     }
  74
  75     sign  = get_bits1(&s->gb);
  76     shift = fcode - 1;
  77     val   = code;
  78     if (shift) {
  79         val  = (val - 1) << shift;
  80         val |= get_bits(&s->gb, shift);
  81         val++;
  82     }
  83     if (sign)
  84         val = -val;
  85     val += pred;
  86
  87     /* modulo decoding */
  88     return sign_extend(val, 5 + shift);
  89 }
  90
  91 static inline int mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
  92 {
  93     int level, dc, diff, i, j, run;
  94     int component;
  95     RLTable *rl = &ff_rl_mpeg1;
  96     uint8_t * const scantable    = s->intra_scantable.permutated;
  97     const uint16_t *quant_matrix = s->intra_matrix;
  98     const int qscale             = s->qscale;
  99
 100     /* DC coefficient */
 101     component = (n <= 3 ? 0 : n - 4 + 1);
 102     diff = decode_dc(&s->gb, component);
 103     if (diff >= 0xffff)
 104         return -1;
 105     dc  = s->last_dc[component];
 106     dc += diff;
 107     s->last_dc[component] = dc;
 108     block[0] = dc * quant_matrix[0];
 109     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
 110     i = 0;
 111     {
 112         OPEN_READER(re, &s->gb);
 113         /* now quantify & encode AC coefficients */
 114         for (;;) {
 115             UPDATE_CACHE(re, &s->gb);
 116             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 117
 118             if (level == 127) {
 119                 break;
 120             } else if (level != 0) {
 121                 i += run;
 122                 j = scantable[i];
 123                 level = (level * qscale * quant_matrix[j]) >> 4;
 124                 level = (level - 1) | 1;
 125                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 126                 LAST_SKIP_BITS(re, &s->gb, 1);
 127             } else {
 128                 /* escape */
 129                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 130                 UPDATE_CACHE(re, &s->gb);
 131                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 132                 if (level == -128) {
 133                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
 134                 } else if (level == 0) {
 135                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
 136                 }
 137                 i += run;
 138                 j = scantable[i];
 139                 if (level < 0) {
 140                     level = -level;
 141                     level = (level * qscale * quant_matrix[j]) >> 4;
 142                     level = (level - 1) | 1;
 143                     level = -level;
 144                 } else {
 145                     level = (level * qscale * quant_matrix[j]) >> 4;
 146                     level = (level - 1) | 1;
 147                 }
 148             }
 149             if (i > 63) {
 150                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 151                 return -1;
 152             }
 153
 154             block[j] = level;
 155         }
 156         CLOSE_READER(re, &s->gb);
 157     }
 158     s->block_last_index[n] = i;
 159    return 0;
 160 }
 161
 162 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 163 {
 164     return mpeg1_decode_block_intra(s, block, n);
 165 }
 166
 167 static inline int mpeg1_decode_block_inter(MpegEncContext *s, int16_t *block, int n)
 168 {
 169     int level, i, j, run;
 170     RLTable *rl = &ff_rl_mpeg1;
 171     uint8_t * const scantable    = s->intra_scantable.permutated;
 172     const uint16_t *quant_matrix = s->inter_matrix;
 173     const int qscale             = s->qscale;
 174
 175     {
 176         OPEN_READER(re, &s->gb);
 177         i = -1;
 178         // special case for first coefficient, no need to add second VLC table
 179         UPDATE_CACHE(re, &s->gb);
 180         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 181             level = (3 * qscale * quant_matrix[0]) >> 5;
 182             level = (level - 1) | 1;
 183             if (GET_CACHE(re, &s->gb) & 0x40000000)
 184                 level = -level;
 185             block[0] = level;
 186             i++;
 187             SKIP_BITS(re, &s->gb, 2);
 188             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 189                 goto end;
 190         }
 191         /* now quantify & encode AC coefficients */
 192         for (;;) {
 193             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 194
 195             if (level != 0) {
 196                 i += run;
 197                 j = scantable[i];
 198                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 199                 level = (level - 1) | 1;
 200                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 201                 SKIP_BITS(re, &s->gb, 1);
 202             } else {
 203                 /* escape */
 204                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 205                 UPDATE_CACHE(re, &s->gb);
 206                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 207                 if (level == -128) {
 208                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 209                 } else if (level == 0) {
 210                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 211                 }
 212                 i += run;
 213                 j = scantable[i];
 214                 if (level < 0) {
 215                     level = -level;
 216                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 217                     level = (level - 1) | 1;
 218                     level = -level;
 219                 } else {
 220                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 221                     level = (level - 1) | 1;
 222                 }
 223             }
 224             if (i > 63) {
 225                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 226                 return -1;
 227             }
 228
 229             block[j] = level;
 230             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 231                 break;
 232             UPDATE_CACHE(re, &s->gb);
 233         }
 234 end:
 235         LAST_SKIP_BITS(re, &s->gb, 2);
 236         CLOSE_READER(re, &s->gb);
 237     }
 238     s->block_last_index[n] = i;
 239     return 0;
 240 }
 241
 242 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, int16_t *block, int n)
 243 {
 244     int level, i, j, run;
 245     RLTable *rl = &ff_rl_mpeg1;
 246     uint8_t * const scantable = s->intra_scantable.permutated;
 247     const int qscale          = s->qscale;
 248
 249     {
 250         OPEN_READER(re, &s->gb);
 251         i = -1;
 252         // special case for first coefficient, no need to add second VLC table
 253         UPDATE_CACHE(re, &s->gb);
 254         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 255             level = (3 * qscale) >> 1;
 256             level = (level - 1) | 1;
 257             if (GET_CACHE(re, &s->gb) & 0x40000000)
 258                 level = -level;
 259             block[0] = level;
 260             i++;
 261             SKIP_BITS(re, &s->gb, 2);
 262             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 263                 goto end;
 264         }
 265
 266         /* now quantify & encode AC coefficients */
 267         for (;;) {
 268             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 269
 270             if (level != 0) {
 271                 i += run;
 272                 j = scantable[i];
 273                 level = ((level * 2 + 1) * qscale) >> 1;
 274                 level = (level - 1) | 1;
 275                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 276                 SKIP_BITS(re, &s->gb, 1);
 277             } else {
 278                 /* escape */
 279                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 280                 UPDATE_CACHE(re, &s->gb);
 281                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 282                 if (level == -128) {
 283                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 284                 } else if (level == 0) {
 285                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 286                 }
 287                 i += run;
 288                 j = scantable[i];
 289                 if (level < 0) {
 290                     level = -level;
 291                     level = ((level * 2 + 1) * qscale) >> 1;
 292                     level = (level - 1) | 1;
 293                     level = -level;
 294                 } else {
 295                     level = ((level * 2 + 1) * qscale) >> 1;
 296                     level = (level - 1) | 1;
 297                 }
 298             }
 299
 300             block[j] = level;
 301             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 302                 break;
 303             UPDATE_CACHE(re, &s->gb);
 304         }
 305 end:
 306         LAST_SKIP_BITS(re, &s->gb, 2);
 307         CLOSE_READER(re, &s->gb);
 308     }
 309     s->block_last_index[n] = i;
 310     return 0;
 311 }
 312
 313
 314 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, int16_t *block, int n)
 315 {
 316     int level, i, j, run;
 317     RLTable *rl = &ff_rl_mpeg1;
 318     uint8_t * const scantable = s->intra_scantable.permutated;
 319     const uint16_t *quant_matrix;
 320     const int qscale = s->qscale;
 321     int mismatch;
 322
 323     mismatch = 1;
 324
 325     {
 326         OPEN_READER(re, &s->gb);
 327         i = -1;
 328         if (n < 4)
 329             quant_matrix = s->inter_matrix;
 330         else
 331             quant_matrix = s->chroma_inter_matrix;
 332
 333         // special case for first coefficient, no need to add second VLC table
 334         UPDATE_CACHE(re, &s->gb);
 335         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 336             level= (3 * qscale * quant_matrix[0]) >> 5;
 337             if (GET_CACHE(re, &s->gb) & 0x40000000)
 338                 level = -level;
 339             block[0]  = level;
 340             mismatch ^= level;
 341             i++;
 342             SKIP_BITS(re, &s->gb, 2);
 343             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 344                 goto end;
 345         }
 346
 347         /* now quantify & encode AC coefficients */
 348         for (;;) {
 349             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 350
 351             if (level != 0) {
 352                 i += run;
 353                 j = scantable[i];
 354                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 355                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 356                 SKIP_BITS(re, &s->gb, 1);
 357             } else {
 358                 /* escape */
 359                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 360                 UPDATE_CACHE(re, &s->gb);
 361                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 362
 363                 i += run;
 364                 j = scantable[i];
 365                 if (level < 0) {
 366                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 367                     level = -level;
 368                 } else {
 369                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
 370                 }
 371             }
 372             if (i > 63) {
 373                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 374                 return -1;
 375             }
 376
 377             mismatch ^= level;
 378             block[j]  = level;
 379             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 380                 break;
 381             UPDATE_CACHE(re, &s->gb);
 382         }
 383 end:
 384         LAST_SKIP_BITS(re, &s->gb, 2);
 385         CLOSE_READER(re, &s->gb);
 386     }
 387     block[63] ^= (mismatch & 1);
 388
 389     s->block_last_index[n] = i;
 390     return 0;
 391 }
 392
 393 static inline int mpeg2_fast_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 int qscale          = s->qscale;
 400     OPEN_READER(re, &s->gb);
 401     i = -1;
 402
 403     // special case for first coefficient, no need to add second VLC table
 404     UPDATE_CACHE(re, &s->gb);
 405     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 406         level = (3 * qscale) >> 1;
 407         if (GET_CACHE(re, &s->gb) & 0x40000000)
 408             level = -level;
 409         block[0] = level;
 410         i++;
 411         SKIP_BITS(re, &s->gb, 2);
 412         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 413             goto end;
 414     }
 415
 416     /* now quantify & encode AC coefficients */
 417     for (;;) {
 418         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 419
 420         if (level != 0) {
 421             i += run;
 422             j  = scantable[i];
 423             level = ((level * 2 + 1) * qscale) >> 1;
 424             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 425             SKIP_BITS(re, &s->gb, 1);
 426         } else {
 427             /* escape */
 428             run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 429             UPDATE_CACHE(re, &s->gb);
 430             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 431
 432             i += run;
 433             j  = scantable[i];
 434             if (level < 0) {
 435                 level = ((-level * 2 + 1) * qscale) >> 1;
 436                 level = -level;
 437             } else {
 438                 level = ((level * 2 + 1) * qscale) >> 1;
 439             }
 440         }
 441
 442         block[j] = level;
 443         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 444             break;
 445         UPDATE_CACHE(re, &s->gb);
 446     }
 447 end:
 448     LAST_SKIP_BITS(re, &s->gb, 2);
 449     CLOSE_READER(re, &s->gb);
 450     s->block_last_index[n] = i;
 451     return 0;
 452 }
 453
 454
 455 static inline int mpeg2_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 456 {
 457     int level, dc, diff, i, j, run;
 458     int component;
 459     RLTable *rl;
 460     uint8_t * const scantable = s->intra_scantable.permutated;
 461     const uint16_t *quant_matrix;
 462     const int qscale = s->qscale;
 463     int mismatch;
 464
 465     /* DC coefficient */
 466     if (n < 4) {
 467         quant_matrix = s->intra_matrix;
 468         component = 0;
 469     } else {
 470         quant_matrix = s->chroma_intra_matrix;
 471         component = (n & 1) + 1;
 472     }
 473     diff = decode_dc(&s->gb, component);
 474     if (diff >= 0xffff)
 475         return -1;
 476     dc  = s->last_dc[component];
 477     dc += diff;
 478     s->last_dc[component] = dc;
 479     block[0] = dc << (3 - s->intra_dc_precision);
 480     av_dlog(s->avctx, "dc=%d\n", block[0]);
 481     mismatch = block[0] ^ 1;
 482     i = 0;
 483     if (s->intra_vlc_format)
 484         rl = &ff_rl_mpeg2;
 485     else
 486         rl = &ff_rl_mpeg1;
 487
 488     {
 489         OPEN_READER(re, &s->gb);
 490         /* now quantify & encode AC coefficients */
 491         for (;;) {
 492             UPDATE_CACHE(re, &s->gb);
 493             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 494
 495             if (level == 127) {
 496                 break;
 497             } else if (level != 0) {
 498                 i += run;
 499                 j  = scantable[i];
 500                 level = (level * qscale * quant_matrix[j]) >> 4;
 501                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 502                 LAST_SKIP_BITS(re, &s->gb, 1);
 503             } else {
 504                 /* escape */
 505                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 506                 UPDATE_CACHE(re, &s->gb);
 507                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 508                 i += run;
 509                 j  = scantable[i];
 510                 if (level < 0) {
 511                     level = (-level * qscale * quant_matrix[j]) >> 4;
 512                     level = -level;
 513                 } else {
 514                     level = (level * qscale * quant_matrix[j]) >> 4;
 515                 }
 516             }
 517             if (i > 63) {
 518                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 519                 return -1;
 520             }
 521
 522             mismatch ^= level;
 523             block[j]  = level;
 524         }
 525         CLOSE_READER(re, &s->gb);
 526     }
 527     block[63] ^= mismatch & 1;
 528
 529     s->block_last_index[n] = i;
 530     return 0;
 531 }
 532
 533 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
 534 {
 535     int level, dc, diff, j, run;
 536     int component;
 537     RLTable *rl;
 538     uint8_t * scantable = s->intra_scantable.permutated;
 539     const uint16_t *quant_matrix;
 540     const int qscale = s->qscale;
 541
 542     /* DC coefficient */
 543     if (n < 4) {
 544         quant_matrix = s->intra_matrix;
 545         component = 0;
 546     } else {
 547         quant_matrix = s->chroma_intra_matrix;
 548         component = (n & 1) + 1;
 549     }
 550     diff = decode_dc(&s->gb, component);
 551     if (diff >= 0xffff)
 552         return -1;
 553     dc = s->last_dc[component];
 554     dc += diff;
 555     s->last_dc[component] = dc;
 556     block[0] = dc << (3 - s->intra_dc_precision);
 557     if (s->intra_vlc_format)
 558         rl = &ff_rl_mpeg2;
 559     else
 560         rl = &ff_rl_mpeg1;
 561
 562     {
 563         OPEN_READER(re, &s->gb);
 564         /* now quantify & encode AC coefficients */
 565         for (;;) {
 566             UPDATE_CACHE(re, &s->gb);
 567             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 568
 569             if (level == 127) {
 570                 break;
 571             } else if (level != 0) {
 572                 scantable += run;
 573                 j = *scantable;
 574                 level = (level * qscale * quant_matrix[j]) >> 4;
 575                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 576                 LAST_SKIP_BITS(re, &s->gb, 1);
 577             } else {
 578                 /* escape */
 579                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
 580                 UPDATE_CACHE(re, &s->gb);
 581                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 582                 scantable += run;
 583                 j = *scantable;
 584                 if (level < 0) {
 585                     level = (-level * qscale * quant_matrix[j]) >> 4;
 586                     level = -level;
 587                 } else {
 588                     level = (level * qscale * quant_matrix[j]) >> 4;
 589                 }
 590             }
 591
 592             block[j] = level;
 593         }
 594         CLOSE_READER(re, &s->gb);
 595     }
 596
 597     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
 598     return 0;
 599 }
 600
 601 /******************************************/
 602 /* decoding */
 603
 604 static inline int get_dmv(MpegEncContext *s)
 605 {
 606     if (get_bits1(&s->gb))
 607         return 1 - (get_bits1(&s->gb) << 1);
 608     else
 609         return 0;
 610 }
 611
 612 static inline int get_qscale(MpegEncContext *s)
 613 {
 614     int qscale = get_bits(&s->gb, 5);
 615     if (s->q_scale_type) {
 616         return non_linear_qscale[qscale];
 617     } else {
 618         return qscale << 1;
 619     }
 620 }
 621
 622 static void exchange_uv(MpegEncContext *s)
 623 {
 624     int16_t (*tmp)[64];
 625
 626     tmp           = s->pblocks[4];
 627     s->pblocks[4] = s->pblocks[5];
 628     s->pblocks[5] = tmp;
 629 }
 630
 631 /* motion type (for MPEG-2) */
 632 #define MT_FIELD 1
 633 #define MT_FRAME 2
 634 #define MT_16X8  2
 635 #define MT_DMV   3
 636
 637 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
 638 {
 639     int i, j, k, cbp, val, mb_type, motion_type;
 640     const int mb_block_count = 4 + (1 << s->chroma_format);
 641
 642     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 643
 644     assert(s->mb_skipped == 0);
 645
 646     if (s->mb_skip_run-- != 0) {
 647         if (s->pict_type == AV_PICTURE_TYPE_P) {
 648             s->mb_skipped = 1;
 649             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 650         } else {
 651             int mb_type;
 652
 653             if (s->mb_x)
 654                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
 655             else
 656                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1]; // FIXME not sure if this is allowed in MPEG at all
 657             if (IS_INTRA(mb_type))
 658                 return -1;
 659             s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride] =
 660                 mb_type | MB_TYPE_SKIP;
 661 //            assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
 662
 663             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
 664                 s->mb_skipped = 1;
 665         }
 666
 667         return 0;
 668     }
 669
 670     switch (s->pict_type) {
 671     default:
 672     case AV_PICTURE_TYPE_I:
 673         if (get_bits1(&s->gb) == 0) {
 674             if (get_bits1(&s->gb) == 0) {
 675                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
 676                 return -1;
 677             }
 678             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 679         } else {
 680             mb_type = MB_TYPE_INTRA;
 681         }
 682         break;
 683     case AV_PICTURE_TYPE_P:
 684         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 685         if (mb_type < 0) {
 686             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 687             return -1;
 688         }
 689         mb_type = ptype2mb_type[mb_type];
 690         break;
 691     case AV_PICTURE_TYPE_B:
 692         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 693         if (mb_type < 0) {
 694             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 695             return -1;
 696         }
 697         mb_type = btype2mb_type[mb_type];
 698         break;
 699     }
 700     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
 701 //    motion_type = 0; /* avoid warning */
 702     if (IS_INTRA(mb_type)) {
 703         s->dsp.clear_blocks(s->block[0]);
 704
 705         if (!s->chroma_y_shift) {
 706             s->dsp.clear_blocks(s->block[6]);
 707         }
 708
 709         /* compute DCT type */
 710         if (s->picture_structure == PICT_FRAME && // FIXME add an interlaced_dct coded var?
 711             !s->frame_pred_frame_dct) {
 712             s->interlaced_dct = get_bits1(&s->gb);
 713         }
 714
 715         if (IS_QUANT(mb_type))
 716             s->qscale = get_qscale(s);
 717
 718         if (s->concealment_motion_vectors) {
 719             /* just parse them */
 720             if (s->picture_structure != PICT_FRAME)
 721                 skip_bits1(&s->gb); /* field select */
 722
 723             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 724                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 725             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 726                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 727
 728             skip_bits1(&s->gb); /* marker */
 729         } else
 730             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 731         s->mb_intra = 1;
 732         // if 1, we memcpy blocks in xvmcvideo
 733         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
 734             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
 735             if (s->swap_uv) {
 736                 exchange_uv(s);
 737             }
 738         }
 739
 740         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 741             if (s->flags2 & CODEC_FLAG2_FAST) {
 742                 for (i = 0; i < 6; i++) {
 743                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 744                 }
 745             } else {
 746                 for (i = 0; i < mb_block_count; i++) {
 747                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
 748                         return -1;
 749                 }
 750             }
 751         } else {
 752             for (i = 0; i < 6; i++) {
 753                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
 754                     return -1;
 755             }
 756         }
 757     } else {
 758         if (mb_type & MB_TYPE_ZERO_MV) {
 759             assert(mb_type & MB_TYPE_CBP);
 760
 761             s->mv_dir = MV_DIR_FORWARD;
 762             if (s->picture_structure == PICT_FRAME) {
 763                 if (!s->frame_pred_frame_dct)
 764                     s->interlaced_dct = get_bits1(&s->gb);
 765                 s->mv_type = MV_TYPE_16X16;
 766             } else {
 767                 s->mv_type = MV_TYPE_FIELD;
 768                 mb_type |= MB_TYPE_INTERLACED;
 769                 s->field_select[0][0] = s->picture_structure - 1;
 770             }
 771
 772             if (IS_QUANT(mb_type))
 773                 s->qscale = get_qscale(s);
 774
 775             s->last_mv[0][0][0] = 0;
 776             s->last_mv[0][0][1] = 0;
 777             s->last_mv[0][1][0] = 0;
 778             s->last_mv[0][1][1] = 0;
 779             s->mv[0][0][0] = 0;
 780             s->mv[0][0][1] = 0;
 781         } else {
 782             assert(mb_type & MB_TYPE_L0L1);
 783             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 784             /* get additional motion vector type */
 785             if (s->frame_pred_frame_dct)
 786                 motion_type = MT_FRAME;
 787             else {
 788                 motion_type = get_bits(&s->gb, 2);
 789                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 790                     s->interlaced_dct = get_bits1(&s->gb);
 791             }
 792
 793             if (IS_QUANT(mb_type))
 794                 s->qscale = get_qscale(s);
 795
 796             /* motion vectors */
 797             s->mv_dir = (mb_type >> 13) & 3;
 798             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
 799             switch (motion_type) {
 800             case MT_FRAME: /* or MT_16X8 */
 801                 if (s->picture_structure == PICT_FRAME) {
 802                     mb_type |= MB_TYPE_16x16;
 803                     s->mv_type = MV_TYPE_16X16;
 804                     for (i = 0; i < 2; i++) {
 805                         if (USES_LIST(mb_type, i)) {
 806                             /* MT_FRAME */
 807                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
 808                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
 809                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
 810                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
 811                             /* full_pel: only for MPEG-1 */
 812                             if (s->full_pel[i]) {
 813                                 s->mv[i][0][0] <<= 1;
 814                                 s->mv[i][0][1] <<= 1;
 815                             }
 816                         }
 817                     }
 818                 } else {
 819                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 820                     s->mv_type = MV_TYPE_16X8;
 821                     for (i = 0; i < 2; i++) {
 822                         if (USES_LIST(mb_type, i)) {
 823                             /* MT_16X8 */
 824                             for (j = 0; j < 2; j++) {
 825                                 s->field_select[i][j] = get_bits1(&s->gb);
 826                                 for (k = 0; k < 2; k++) {
 827                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 828                                                              s->last_mv[i][j][k]);
 829                                     s->last_mv[i][j][k] = val;
 830                                     s->mv[i][j][k]      = val;
 831                                 }
 832                             }
 833                         }
 834                     }
 835                 }
 836                 break;
 837             case MT_FIELD:
 838                 s->mv_type = MV_TYPE_FIELD;
 839                 if (s->picture_structure == PICT_FRAME) {
 840                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 841                     for (i = 0; i < 2; i++) {
 842                         if (USES_LIST(mb_type, i)) {
 843                             for (j = 0; j < 2; j++) {
 844                                 s->field_select[i][j] = get_bits1(&s->gb);
 845                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 846                                                          s->last_mv[i][j][0]);
 847                                 s->last_mv[i][j][0] = val;
 848                                 s->mv[i][j][0]      = val;
 849                                 av_dlog(s->avctx, "fmx=%d\n", val);
 850                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 851                                                          s->last_mv[i][j][1] >> 1);
 852                                 s->last_mv[i][j][1] = val << 1;
 853                                 s->mv[i][j][1]      = val;
 854                                 av_dlog(s->avctx, "fmy=%d\n", val);
 855                             }
 856                         }
 857                     }
 858                 } else {
 859                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 860                     for (i = 0; i < 2; i++) {
 861                         if (USES_LIST(mb_type, i)) {
 862                             s->field_select[i][0] = get_bits1(&s->gb);
 863                             for (k = 0; k < 2; k++) {
 864                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 865                                                          s->last_mv[i][0][k]);
 866                                 s->last_mv[i][0][k] = val;
 867                                 s->last_mv[i][1][k] = val;
 868                                 s->mv[i][0][k]      = val;
 869                             }
 870                         }
 871                     }
 872                 }
 873                 break;
 874             case MT_DMV:
 875                 s->mv_type = MV_TYPE_DMV;
 876                 for (i = 0; i < 2; i++) {
 877                     if (USES_LIST(mb_type, i)) {
 878                         int dmx, dmy, mx, my, m;
 879                         const int my_shift = s->picture_structure == PICT_FRAME;
 880
 881                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 882                                                 s->last_mv[i][0][0]);
 883                         s->last_mv[i][0][0] = mx;
 884                         s->last_mv[i][1][0] = mx;
 885                         dmx = get_dmv(s);
 886                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 887                                                  s->last_mv[i][0][1] >> my_shift);
 888                         dmy = get_dmv(s);
 889
 890
 891                         s->last_mv[i][0][1] = my << my_shift;
 892                         s->last_mv[i][1][1] = my << my_shift;
 893
 894                         s->mv[i][0][0] = mx;
 895                         s->mv[i][0][1] = my;
 896                         s->mv[i][1][0] = mx; // not used
 897                         s->mv[i][1][1] = my; // not used
 898
 899                         if (s->picture_structure == PICT_FRAME) {
 900                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 901
 902                             // m = 1 + 2 * s->top_field_first;
 903                             m = s->top_field_first ? 1 : 3;
 904
 905                             /* top -> top pred */
 906                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 907                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 908                             m = 4 - m;
 909                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 910                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 911                         } else {
 912                             mb_type |= MB_TYPE_16x16;
 913
 914                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 915                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 916                             if (s->picture_structure == PICT_TOP_FIELD)
 917                                 s->mv[i][2][1]--;
 918                             else
 919                                 s->mv[i][2][1]++;
 920                         }
 921                     }
 922                 }
 923                 break;
 924             default:
 925                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 926                 return -1;
 927             }
 928         }
 929
 930         s->mb_intra = 0;
 931         if (HAS_CBP(mb_type)) {
 932             s->dsp.clear_blocks(s->block[0]);
 933
 934             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 935             if (mb_block_count > 6) {
 936                  cbp <<= mb_block_count - 6;
 937                  cbp  |= get_bits(&s->gb, mb_block_count - 6);
 938                  s->dsp.clear_blocks(s->block[6]);
 939             }
 940             if (cbp <= 0) {
 941                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
 942                 return -1;
 943             }
 944
 945             //if 1, we memcpy blocks in xvmcvideo
 946             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
 947                 ff_xvmc_pack_pblocks(s, cbp);
 948                 if (s->swap_uv) {
 949                     exchange_uv(s);
 950                 }
 951             }
 952
 953             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
 954                 if (s->flags2 & CODEC_FLAG2_FAST) {
 955                     for (i = 0; i < 6; i++) {
 956                         if (cbp & 32) {
 957                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
 958                         } else {
 959                             s->block_last_index[i] = -1;
 960                         }
 961                         cbp += cbp;
 962                     }
 963                 } else {
 964                     cbp <<= 12-mb_block_count;
 965
 966                     for (i = 0; i < mb_block_count; i++) {
 967                         if (cbp & (1 << 11)) {
 968                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
 969                                 return -1;
 970                         } else {
 971                             s->block_last_index[i] = -1;
 972                         }
 973                         cbp += cbp;
 974                     }
 975                 }
 976             } else {
 977                 if (s->flags2 & CODEC_FLAG2_FAST) {
 978                     for (i = 0; i < 6; i++) {
 979                         if (cbp & 32) {
 980                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
 981                         } else {
 982                             s->block_last_index[i] = -1;
 983                         }
 984                         cbp += cbp;
 985                     }
 986                 } else {
 987                     for (i = 0; i < 6; i++) {
 988                         if (cbp & 32) {
 989                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
 990                                 return -1;
 991                         } else {
 992                             s->block_last_index[i] = -1;
 993                         }
 994                         cbp += cbp;
 995                     }
 996                 }
 997             }
 998         } else {
 999             for (i = 0; i < 12; i++)
1000                 s->block_last_index[i] = -1;
1001         }
1002     }
1003
1004     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1005
1006     return 0;
1007 }
1008
1009 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1010 {
1011     Mpeg1Context *s = avctx->priv_data;
1012     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1013     int i;
1014
1015     /* we need some permutation to store matrices,
1016      * until MPV_common_init() sets the real permutation. */
1017     for (i = 0; i < 64; i++)
1018        s2->dsp.idct_permutation[i]=i;
1019
1020     ff_MPV_decode_defaults(s2);
1021
1022     s->mpeg_enc_ctx.avctx  = avctx;
1023     s->mpeg_enc_ctx.flags  = avctx->flags;
1024     s->mpeg_enc_ctx.flags2 = avctx->flags2;
1025     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1026     ff_mpeg12_init_vlcs();
1027
1028     s->mpeg_enc_ctx_allocated      = 0;
1029     s->mpeg_enc_ctx.picture_number = 0;
1030     s->repeat_field                = 0;
1031     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1032     avctx->color_range = AVCOL_RANGE_MPEG;
1033     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1034         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1035     else
1036         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1037     return 0;
1038 }
1039
1040 static int mpeg_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
1041 {
1042     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1043     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1044     int err;
1045
1046     if (avctx == avctx_from || !ctx_from->mpeg_enc_ctx_allocated || !s1->context_initialized)
1047         return 0;
1048
1049     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1050     if (err) return err;
1051
1052     if (!ctx->mpeg_enc_ctx_allocated)
1053         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1054
1055     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1056         s->picture_number++;
1057
1058     return 0;
1059 }
1060
1061 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1062                                  const uint8_t *new_perm)
1063 {
1064     uint16_t temp_matrix[64];
1065     int i;
1066
1067     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1068
1069     for (i = 0; i < 64; i++) {
1070         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1071     }
1072 }
1073
1074 static const enum AVPixelFormat pixfmt_xvmc_mpg2_420[] = {
1075     AV_PIX_FMT_XVMC_MPEG2_IDCT,
1076     AV_PIX_FMT_XVMC_MPEG2_MC,
1077     AV_PIX_FMT_NONE };
1078
1079 static const enum AVPixelFormat mpeg12_hwaccel_pixfmt_list_420[] = {
1080 #if CONFIG_MPEG2_DXVA2_HWACCEL
1081     AV_PIX_FMT_DXVA2_VLD,
1082 #endif
1083 #if CONFIG_MPEG2_VAAPI_HWACCEL
1084     AV_PIX_FMT_VAAPI_VLD,
1085 #endif
1086 #if CONFIG_MPEG1_VDPAU_HWACCEL | CONFIG_MPEG2_VDPAU_HWACCEL
1087     AV_PIX_FMT_VDPAU,
1088 #endif
1089     AV_PIX_FMT_YUV420P,
1090     AV_PIX_FMT_NONE
1091 };
1092
1093 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1094 {
1095     Mpeg1Context *s1 = avctx->priv_data;
1096     MpegEncContext *s = &s1->mpeg_enc_ctx;
1097
1098     if (avctx->xvmc_acceleration)
1099         return avctx->get_format(avctx, pixfmt_xvmc_mpg2_420);
1100     else if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
1101         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO)
1102             return AV_PIX_FMT_VDPAU_MPEG1;
1103         else
1104             return AV_PIX_FMT_VDPAU_MPEG2;
1105     } else {
1106         if (s->chroma_format <  2)
1107             return avctx->get_format(avctx, mpeg12_hwaccel_pixfmt_list_420);
1108         else if (s->chroma_format == 2)
1109             return AV_PIX_FMT_YUV422P;
1110         else
1111             return AV_PIX_FMT_YUV444P;
1112     }
1113 }
1114
1115 /* Call this function when we know all parameters.
1116  * It may be called in different places for MPEG-1 and MPEG-2. */
1117 static int mpeg_decode_postinit(AVCodecContext *avctx)
1118 {
1119     Mpeg1Context *s1 = avctx->priv_data;
1120     MpegEncContext *s = &s1->mpeg_enc_ctx;
1121     uint8_t old_permutation[64];
1122
1123     if ((s1->mpeg_enc_ctx_allocated == 0) ||
1124         avctx->coded_width  != s->width   ||
1125         avctx->coded_height != s->height  ||
1126         s1->save_width           != s->width                ||
1127         s1->save_height          != s->height               ||
1128         s1->save_aspect_info     != s->aspect_ratio_info    ||
1129         s1->save_progressive_seq != s->progressive_sequence ||
1130         0)
1131     {
1132
1133         if (s1->mpeg_enc_ctx_allocated) {
1134             ParseContext pc = s->parse_context;
1135             s->parse_context.buffer = 0;
1136             ff_MPV_common_end(s);
1137             s->parse_context = pc;
1138         }
1139
1140         if ((s->width == 0) || (s->height == 0))
1141             return -2;
1142
1143         avcodec_set_dimensions(avctx, s->width, s->height);
1144         avctx->bit_rate          = s->bit_rate;
1145         s1->save_aspect_info     = s->aspect_ratio_info;
1146         s1->save_width           = s->width;
1147         s1->save_height          = s->height;
1148         s1->save_progressive_seq = s->progressive_sequence;
1149
1150         /* low_delay may be forced, in this case we will have B-frames
1151          * that behave like P-frames. */
1152         avctx->has_b_frames = !s->low_delay;
1153
1154         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1155             //MPEG-1 fps
1156             avctx->time_base.den = ff_mpeg12_frame_rate_tab[s->frame_rate_index].num;
1157             avctx->time_base.num = ff_mpeg12_frame_rate_tab[s->frame_rate_index].den;
1158             //MPEG-1 aspect
1159             avctx->sample_aspect_ratio = av_d2q(1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1160             avctx->ticks_per_frame=1;
1161         } else {//MPEG-2
1162         //MPEG-2 fps
1163             av_reduce(&s->avctx->time_base.den,
1164                       &s->avctx->time_base.num,
1165                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
1166                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1167                       1 << 30);
1168             avctx->ticks_per_frame = 2;
1169             //MPEG-2 aspect
1170             if (s->aspect_ratio_info > 1) {
1171                 AVRational dar =
1172                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1173                                       (AVRational) {s1->pan_scan.width, s1->pan_scan.height}),
1174                              (AVRational) {s->width, s->height});
1175
1176                 // we ignore the spec here and guess a bit as reality does not match the spec, see for example
1177                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1178                 // issue1613, 621, 562
1179                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1180                    (av_cmp_q(dar, (AVRational) {4, 3}) && av_cmp_q(dar, (AVRational) {16, 9}))) {
1181                     s->avctx->sample_aspect_ratio =
1182                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1183                                  (AVRational) {s->width, s->height});
1184                 } else {
1185                     s->avctx->sample_aspect_ratio =
1186                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1187                                  (AVRational) {s1->pan_scan.width, s1->pan_scan.height});
1188 //issue1613 4/3 16/9 -> 16/9
1189 //res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1190 //widescreen-issue562.mpg 4/3 16/9 -> 16/9
1191 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1192                     av_dlog(avctx, "A %d/%d\n",
1193                             ff_mpeg2_aspect[s->aspect_ratio_info].num, ff_mpeg2_aspect[s->aspect_ratio_info].den);
1194                     av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1195                             s->avctx->sample_aspect_ratio.den);
1196                 }
1197             } else {
1198                 s->avctx->sample_aspect_ratio =
1199                     ff_mpeg2_aspect[s->aspect_ratio_info];
1200             }
1201         } // MPEG-2
1202
1203         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1204         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1205         // until then pix_fmt may be changed right after codec init
1206         if (avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT ||
1207             avctx->hwaccel                            ||
1208             s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
1209             if (avctx->idct_algo == FF_IDCT_AUTO)
1210                 avctx->idct_algo = FF_IDCT_SIMPLE;
1211
1212         /* Quantization matrices may need reordering
1213          * if DCT permutation is changed. */
1214         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
1215
1216         if (ff_MPV_common_init(s) < 0)
1217             return -2;
1218
1219         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
1220         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->dsp.idct_permutation);
1221         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->dsp.idct_permutation);
1222         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->dsp.idct_permutation);
1223
1224         s1->mpeg_enc_ctx_allocated = 1;
1225     }
1226     return 0;
1227 }
1228
1229 static int mpeg1_decode_picture(AVCodecContext *avctx,
1230                                 const uint8_t *buf, int buf_size)
1231 {
1232     Mpeg1Context *s1 = avctx->priv_data;
1233     MpegEncContext *s = &s1->mpeg_enc_ctx;
1234     int ref, f_code, vbv_delay;
1235
1236     init_get_bits(&s->gb, buf, buf_size*8);
1237
1238     ref = get_bits(&s->gb, 10); /* temporal ref */
1239     s->pict_type = get_bits(&s->gb, 3);
1240     if (s->pict_type == 0 || s->pict_type > 3)
1241         return -1;
1242
1243     vbv_delay = get_bits(&s->gb, 16);
1244     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) {
1245         s->full_pel[0] = get_bits1(&s->gb);
1246         f_code = get_bits(&s->gb, 3);
1247         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1248             return -1;
1249         s->mpeg_f_code[0][0] = f_code;
1250         s->mpeg_f_code[0][1] = f_code;
1251     }
1252     if (s->pict_type == AV_PICTURE_TYPE_B) {
1253         s->full_pel[1] = get_bits1(&s->gb);
1254         f_code = get_bits(&s->gb, 3);
1255         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1256             return -1;
1257         s->mpeg_f_code[1][0] = f_code;
1258         s->mpeg_f_code[1][1] = f_code;
1259     }
1260     s->current_picture.f.pict_type = s->pict_type;
1261     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1262
1263     if (avctx->debug & FF_DEBUG_PICT_INFO)
1264         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1265
1266     s->y_dc_scale = 8;
1267     s->c_dc_scale = 8;
1268     return 0;
1269 }
1270
1271 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1272 {
1273     MpegEncContext *s= &s1->mpeg_enc_ctx;
1274     int horiz_size_ext, vert_size_ext;
1275     int bit_rate_ext;
1276
1277     skip_bits(&s->gb, 1); /* profile and level esc*/
1278     s->avctx->profile       = get_bits(&s->gb, 3);
1279     s->avctx->level         = get_bits(&s->gb, 4);
1280     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1281     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1282     horiz_size_ext          = get_bits(&s->gb, 2);
1283     vert_size_ext           = get_bits(&s->gb, 2);
1284     s->width  |= (horiz_size_ext << 12);
1285     s->height |= (vert_size_ext  << 12);
1286     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1287     s->bit_rate += (bit_rate_ext << 18) * 400;
1288     skip_bits1(&s->gb); /* marker */
1289     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1290
1291     s->low_delay = get_bits1(&s->gb);
1292     if (s->flags & CODEC_FLAG_LOW_DELAY)
1293         s->low_delay = 1;
1294
1295     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1296     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1297
1298     av_dlog(s->avctx, "sequence extension\n");
1299     s->codec_id      = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1300
1301     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1302         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1303                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1304
1305 }
1306
1307 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1308 {
1309     MpegEncContext *s = &s1->mpeg_enc_ctx;
1310     int color_description, w, h;
1311
1312     skip_bits(&s->gb, 3); /* video format */
1313     color_description = get_bits1(&s->gb);
1314     if (color_description) {
1315         s->avctx->color_primaries = get_bits(&s->gb, 8);
1316         s->avctx->color_trc       = get_bits(&s->gb, 8);
1317         s->avctx->colorspace      = get_bits(&s->gb, 8);
1318     }
1319     w = get_bits(&s->gb, 14);
1320     skip_bits(&s->gb, 1); //marker
1321     h = get_bits(&s->gb, 14);
1322     // remaining 3 bits are zero padding
1323
1324     s1->pan_scan.width  = 16 * w;
1325     s1->pan_scan.height = 16 * h;
1326
1327     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1328         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1329 }
1330
1331 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1332 {
1333     MpegEncContext *s = &s1->mpeg_enc_ctx;
1334     int i, nofco;
1335
1336     nofco = 1;
1337     if (s->progressive_sequence) {
1338         if (s->repeat_first_field) {
1339             nofco++;
1340             if (s->top_field_first)
1341                 nofco++;
1342         }
1343     } else {
1344         if (s->picture_structure == PICT_FRAME) {
1345             nofco++;
1346             if (s->repeat_first_field)
1347                 nofco++;
1348         }
1349     }
1350     for (i = 0; i < nofco; i++) {
1351         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1352         skip_bits(&s->gb, 1); // marker
1353         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1354         skip_bits(&s->gb, 1); // marker
1355     }
1356
1357     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1358         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1359                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1360                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1361                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1362 }
1363
1364 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra)
1365 {
1366     int i;
1367
1368     for (i = 0; i < 64; i++) {
1369         int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
1370         int v = get_bits(&s->gb, 8);
1371         if (v == 0) {
1372             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1373             return -1;
1374         }
1375         if (intra && i == 0 && v != 8) {
1376             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1377             v = 8; // needed by pink.mpg / issue1046
1378         }
1379         matrix0[j] = v;
1380         if (matrix1)
1381             matrix1[j] = v;
1382     }
1383     return 0;
1384 }
1385
1386 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1387 {
1388     av_dlog(s->avctx, "matrix extension\n");
1389
1390     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1391     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1392     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
1393     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
1394 }
1395
1396 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1397 {
1398     MpegEncContext *s = &s1->mpeg_enc_ctx;
1399
1400     s->full_pel[0] = s->full_pel[1] = 0;
1401     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1402     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1403     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1404     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1405     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1406         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1407         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1408             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1409                 s->pict_type = AV_PICTURE_TYPE_I;
1410             else
1411                 s->pict_type = AV_PICTURE_TYPE_P;
1412         } else
1413             s->pict_type = AV_PICTURE_TYPE_B;
1414         s->current_picture.f.pict_type = s->pict_type;
1415         s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1416     }
1417     s->intra_dc_precision         = get_bits(&s->gb, 2);
1418     s->picture_structure          = get_bits(&s->gb, 2);
1419     s->top_field_first            = get_bits1(&s->gb);
1420     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1421     s->concealment_motion_vectors = get_bits1(&s->gb);
1422     s->q_scale_type               = get_bits1(&s->gb);
1423     s->intra_vlc_format           = get_bits1(&s->gb);
1424     s->alternate_scan             = get_bits1(&s->gb);
1425     s->repeat_first_field         = get_bits1(&s->gb);
1426     s->chroma_420_type            = get_bits1(&s->gb);
1427     s->progressive_frame          = get_bits1(&s->gb);
1428
1429     if (s->progressive_sequence && !s->progressive_frame) {
1430         s->progressive_frame = 1;
1431         av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
1432     }
1433
1434     if (s->picture_structure == 0 || (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
1435         av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
1436         s->picture_structure = PICT_FRAME;
1437     }
1438
1439     if (s->progressive_sequence && !s->frame_pred_frame_dct) {
1440         av_log(s->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
1441     }
1442
1443     if (s->picture_structure == PICT_FRAME) {
1444         s->first_field = 0;
1445         s->v_edge_pos  = 16 * s->mb_height;
1446     } else {
1447         s->first_field ^= 1;
1448         s->v_edge_pos   = 8 * s->mb_height;
1449         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
1450     }
1451
1452     if (s->alternate_scan) {
1453         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1454         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1455     } else {
1456         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1457         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1458     }
1459
1460     /* composite display not parsed */
1461     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1462     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1463     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1464     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1465     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1466     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1467     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1468     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1469     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1470 }
1471
1472 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1473 {
1474     AVCodecContext *avctx = s->avctx;
1475     Mpeg1Context *s1 = (Mpeg1Context*)s;
1476
1477     /* start frame decoding */
1478     if (s->first_field || s->picture_structure == PICT_FRAME) {
1479         AVFrameSideData *pan_scan;
1480
1481         if (ff_MPV_frame_start(s, avctx) < 0)
1482             return -1;
1483
1484         ff_mpeg_er_frame_start(s);
1485
1486         /* first check if we must repeat the frame */
1487         s->current_picture_ptr->f.repeat_pict = 0;
1488         if (s->repeat_first_field) {
1489             if (s->progressive_sequence) {
1490                 if (s->top_field_first)
1491                     s->current_picture_ptr->f.repeat_pict = 4;
1492                 else
1493                     s->current_picture_ptr->f.repeat_pict = 2;
1494             } else if (s->progressive_frame) {
1495                 s->current_picture_ptr->f.repeat_pict = 1;
1496             }
1497         }
1498
1499         pan_scan = av_frame_new_side_data(&s->current_picture_ptr->f,
1500                                           AV_FRAME_DATA_PANSCAN,
1501                                           sizeof(s1->pan_scan));
1502         if (!pan_scan)
1503             return AVERROR(ENOMEM);
1504         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1505
1506         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1507             ff_thread_finish_setup(avctx);
1508     } else { // second field
1509         int i;
1510
1511         if (!s->current_picture_ptr) {
1512             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1513             return -1;
1514         }
1515
1516         if (s->avctx->hwaccel &&
1517             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1518             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1519                 av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode first field\n");
1520         }
1521
1522         for (i = 0; i < 4; i++) {
1523             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
1524             if (s->picture_structure == PICT_BOTTOM_FIELD) {
1525                 s->current_picture.f.data[i] += s->current_picture_ptr->f.linesize[i];
1526             }
1527         }
1528     }
1529
1530     if (avctx->hwaccel) {
1531         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1532             return -1;
1533     }
1534
1535 // MPV_frame_start will call this function too,
1536 // but we need to call it on every field
1537     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1538         if (ff_xvmc_field_start(s, avctx) < 0)
1539             return -1;
1540
1541     return 0;
1542 }
1543
1544 #define DECODE_SLICE_ERROR -1
1545 #define DECODE_SLICE_OK     0
1546
1547 /**
1548  * Decode a slice.
1549  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1550  * @return DECODE_SLICE_ERROR if the slice is damaged,
1551  *         DECODE_SLICE_OK if this slice is OK
1552  */
1553 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1554                              const uint8_t **buf, int buf_size)
1555 {
1556     AVCodecContext *avctx = s->avctx;
1557     const int field_pic   = s->picture_structure != PICT_FRAME;
1558
1559     s->resync_mb_x =
1560     s->resync_mb_y = -1;
1561
1562     assert(mb_y < s->mb_height);
1563
1564     init_get_bits(&s->gb, *buf, buf_size * 8);
1565
1566     ff_mpeg1_clean_buffers(s);
1567     s->interlaced_dct = 0;
1568
1569     s->qscale = get_qscale(s);
1570
1571     if (s->qscale == 0) {
1572         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1573         return -1;
1574     }
1575
1576     /* extra slice info */
1577     while (get_bits1(&s->gb) != 0) {
1578         skip_bits(&s->gb, 8);
1579     }
1580
1581     s->mb_x = 0;
1582
1583     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1584         skip_bits1(&s->gb);
1585     } else {
1586         while (get_bits_left(&s->gb) > 0) {
1587             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1588                                 MBINCR_VLC_BITS, 2);
1589             if (code < 0) {
1590                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1591                 return -1;
1592             }
1593             if (code >= 33) {
1594                 if (code == 33) {
1595                     s->mb_x += 33;
1596                 }
1597                 /* otherwise, stuffing, nothing to do */
1598             } else {
1599                 s->mb_x += code;
1600                 break;
1601             }
1602         }
1603     }
1604
1605     if (s->mb_x >= (unsigned)s->mb_width) {
1606         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1607         return -1;
1608     }
1609
1610     if (avctx->hwaccel) {
1611         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1612         int start_code = -1;
1613         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1614         if (buf_end < *buf + buf_size)
1615             buf_end -= 4;
1616         s->mb_y = mb_y;
1617         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1618             return DECODE_SLICE_ERROR;
1619         *buf = buf_end;
1620         return DECODE_SLICE_OK;
1621     }
1622
1623     s->resync_mb_x = s->mb_x;
1624     s->resync_mb_y = s->mb_y = mb_y;
1625     s->mb_skip_run = 0;
1626     ff_init_block_index(s);
1627
1628     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1629         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1630              av_log(s->avctx, AV_LOG_DEBUG, "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",
1631                     s->qscale, s->mpeg_f_code[0][0], s->mpeg_f_code[0][1], s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1632                     s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1633                     s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1634                     s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1635                     s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1636         }
1637     }
1638
1639     for (;;) {
1640         // If 1, we memcpy blocks in xvmcvideo.
1641         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1642             ff_xvmc_init_block(s); // set s->block
1643
1644         if (mpeg_decode_mb(s, s->block) < 0)
1645             return -1;
1646
1647         if (s->current_picture.motion_val[0] && !s->encoding) { // note motion_val is normally NULL unless we want to extract the MVs
1648             const int wrap = s->b8_stride;
1649             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1650             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1651             int motion_x, motion_y, dir, i;
1652
1653             for (i = 0; i < 2; i++) {
1654                 for (dir = 0; dir < 2; dir++) {
1655                     if (s->mb_intra || (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1656                         motion_x = motion_y = 0;
1657                     } else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1658                         motion_x = s->mv[dir][0][0];
1659                         motion_y = s->mv[dir][0][1];
1660                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1661                         motion_x = s->mv[dir][i][0];
1662                         motion_y = s->mv[dir][i][1];
1663                     }
1664
1665                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1666                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1667                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1668                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1669                     s->current_picture.ref_index [dir][b8_xy    ] =
1670                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1671                     assert(s->field_select[dir][i] == 0 || s->field_select[dir][i] == 1);
1672                 }
1673                 xy += wrap;
1674                 b8_xy +=2;
1675             }
1676         }
1677
1678         s->dest[0] += 16;
1679         s->dest[1] += 16 >> s->chroma_x_shift;
1680         s->dest[2] += 16 >> s->chroma_x_shift;
1681
1682         ff_MPV_decode_mb(s, s->block);
1683
1684         if (++s->mb_x >= s->mb_width) {
1685             const int mb_size = 16;
1686
1687             ff_mpeg_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
1688             ff_MPV_report_decode_progress(s);
1689
1690             s->mb_x = 0;
1691             s->mb_y += 1 << field_pic;
1692
1693             if (s->mb_y >= s->mb_height) {
1694                 int left   = get_bits_left(&s->gb);
1695                 int is_d10 = s->chroma_format == 2 && s->pict_type == AV_PICTURE_TYPE_I && avctx->profile == 0 && avctx->level == 5
1696                              && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1697                              && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1698
1699                 if (left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1700                     || ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
1701                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1702                     return -1;
1703                 } else
1704                     goto eos;
1705             }
1706
1707             ff_init_block_index(s);
1708         }
1709
1710         /* skip mb handling */
1711         if (s->mb_skip_run == -1) {
1712             /* read increment again */
1713             s->mb_skip_run = 0;
1714             for (;;) {
1715                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1716                                     MBINCR_VLC_BITS, 2);
1717                 if (code < 0) {
1718                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1719                     return -1;
1720                 }
1721                 if (code >= 33) {
1722                     if (code == 33) {
1723                         s->mb_skip_run += 33;
1724                     } else if (code == 35) {
1725                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1726                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1727                             return -1;
1728                         }
1729                         goto eos; /* end of slice */
1730                     }
1731                     /* otherwise, stuffing, nothing to do */
1732                 } else {
1733                     s->mb_skip_run += code;
1734                     break;
1735                 }
1736             }
1737             if (s->mb_skip_run) {
1738                 int i;
1739                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1740                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1741                     return -1;
1742                 }
1743
1744                 /* skip mb */
1745                 s->mb_intra = 0;
1746                 for (i = 0; i < 12; i++)
1747                     s->block_last_index[i] = -1;
1748                 if (s->picture_structure == PICT_FRAME)
1749                     s->mv_type = MV_TYPE_16X16;
1750                 else
1751                     s->mv_type = MV_TYPE_FIELD;
1752                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1753                     /* if P type, zero motion vector is implied */
1754                     s->mv_dir             = MV_DIR_FORWARD;
1755                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1756                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1757                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1758                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1759                 } else {
1760                     /* if B type, reuse previous vectors and directions */
1761                     s->mv[0][0][0] = s->last_mv[0][0][0];
1762                     s->mv[0][0][1] = s->last_mv[0][0][1];
1763                     s->mv[1][0][0] = s->last_mv[1][0][0];
1764                     s->mv[1][0][1] = s->last_mv[1][0][1];
1765                 }
1766             }
1767         }
1768     }
1769 eos: // end of slice
1770     *buf += (get_bits_count(&s->gb)-1)/8;
1771     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1772     return 0;
1773 }
1774
1775 static int slice_decode_thread(AVCodecContext *c, void *arg)
1776 {
1777     MpegEncContext *s   = *(void**)arg;
1778     const uint8_t *buf  = s->gb.buffer;
1779     int mb_y            = s->start_mb_y;
1780     const int field_pic = s->picture_structure != PICT_FRAME;
1781
1782     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1783
1784     for (;;) {
1785         uint32_t start_code;
1786         int ret;
1787
1788         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1789         emms_c();
1790         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1791                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
1792                 s->start_mb_y, s->end_mb_y, s->er.error_count);
1793         if (ret < 0) {
1794             if (c->err_recognition & AV_EF_EXPLODE)
1795                 return ret;
1796             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1797                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
1798         } else {
1799             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
1800         }
1801
1802         if (s->mb_y == s->end_mb_y)
1803             return 0;
1804
1805         start_code = -1;
1806         buf = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
1807         mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
1808         if (s->picture_structure == PICT_BOTTOM_FIELD)
1809             mb_y++;
1810         if (mb_y < 0 || mb_y >= s->end_mb_y)
1811             return -1;
1812     }
1813 }
1814
1815 /**
1816  * Handle slice ends.
1817  * @return 1 if it seems to be the last slice
1818  */
1819 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1820 {
1821     Mpeg1Context *s1 = avctx->priv_data;
1822     MpegEncContext *s = &s1->mpeg_enc_ctx;
1823
1824     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1825         return 0;
1826
1827     if (s->avctx->hwaccel) {
1828         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1829             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
1830     }
1831
1832     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1833         ff_xvmc_field_end(s);
1834
1835     /* end of slice reached */
1836     if (/*s->mb_y << field_pic == s->mb_height &&*/ !s->first_field) {
1837         /* end of image */
1838
1839         ff_er_frame_end(&s->er);
1840
1841         ff_MPV_frame_end(s);
1842
1843         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
1844             int ret = av_frame_ref(pict, &s->current_picture_ptr->f);
1845             if (ret < 0)
1846                 return ret;
1847             ff_print_debug_info(s, s->current_picture_ptr);
1848         } else {
1849             if (avctx->active_thread_type & FF_THREAD_FRAME)
1850                 s->picture_number++;
1851             /* latency of 1 frame for I- and P-frames */
1852             /* XXX: use another variable than picture_number */
1853             if (s->last_picture_ptr != NULL) {
1854                 int ret = av_frame_ref(pict, &s->last_picture_ptr->f);
1855                 if (ret < 0)
1856                     return ret;
1857                 ff_print_debug_info(s, s->last_picture_ptr);
1858             }
1859         }
1860
1861         return 1;
1862     } else {
1863         return 0;
1864     }
1865 }
1866
1867 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1868                                  const uint8_t *buf, int buf_size)
1869 {
1870     Mpeg1Context *s1 = avctx->priv_data;
1871     MpegEncContext *s = &s1->mpeg_enc_ctx;
1872     int width, height;
1873     int i, v, j;
1874
1875     init_get_bits(&s->gb, buf, buf_size*8);
1876
1877     width  = get_bits(&s->gb, 12);
1878     height = get_bits(&s->gb, 12);
1879     if (width == 0 || height == 0) {
1880         av_log(avctx, AV_LOG_WARNING, "Invalid horizontal or vertical size "
1881                "value.\n");
1882         if (avctx->err_recognition & AV_EF_BITSTREAM)
1883             return AVERROR_INVALIDDATA;
1884     }
1885     s->aspect_ratio_info = get_bits(&s->gb, 4);
1886     if (s->aspect_ratio_info == 0) {
1887         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1888         if (avctx->err_recognition & AV_EF_BITSTREAM)
1889             return -1;
1890     }
1891     s->frame_rate_index = get_bits(&s->gb, 4);
1892     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1893         return -1;
1894     s->bit_rate = get_bits(&s->gb, 18) * 400;
1895     if (get_bits1(&s->gb) == 0) /* marker */
1896         return -1;
1897     s->width  = width;
1898     s->height = height;
1899
1900     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
1901     skip_bits(&s->gb, 1);
1902
1903     /* get matrix */
1904     if (get_bits1(&s->gb)) {
1905         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1906     } else {
1907         for (i = 0; i < 64; i++) {
1908             j = s->dsp.idct_permutation[i];
1909             v = ff_mpeg1_default_intra_matrix[i];
1910             s->intra_matrix[j]        = v;
1911             s->chroma_intra_matrix[j] = v;
1912         }
1913     }
1914     if (get_bits1(&s->gb)) {
1915         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1916     } else {
1917         for (i = 0; i < 64; i++) {
1918             int j = s->dsp.idct_permutation[i];
1919             v = ff_mpeg1_default_non_intra_matrix[i];
1920             s->inter_matrix[j]        = v;
1921             s->chroma_inter_matrix[j] = v;
1922         }
1923     }
1924
1925     if (show_bits(&s->gb, 23) != 0) {
1926         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
1927         return -1;
1928     }
1929
1930     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
1931     s->progressive_sequence = 1;
1932     s->progressive_frame    = 1;
1933     s->picture_structure    = PICT_FRAME;
1934     s->frame_pred_frame_dct = 1;
1935     s->chroma_format        = 1;
1936     s->codec_id             = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
1937     s->out_format           = FMT_MPEG1;
1938     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
1939     if (s->flags & CODEC_FLAG_LOW_DELAY)
1940         s->low_delay = 1;
1941
1942     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1943         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
1944                s->avctx->rc_buffer_size, s->bit_rate);
1945
1946     return 0;
1947 }
1948
1949 static int vcr2_init_sequence(AVCodecContext *avctx)
1950 {
1951     Mpeg1Context *s1 = avctx->priv_data;
1952     MpegEncContext *s = &s1->mpeg_enc_ctx;
1953     int i, v;
1954
1955     /* start new MPEG-1 context decoding */
1956     s->out_format = FMT_MPEG1;
1957     if (s1->mpeg_enc_ctx_allocated) {
1958         ff_MPV_common_end(s);
1959     }
1960     s->width  = avctx->coded_width;
1961     s->height = avctx->coded_height;
1962     avctx->has_b_frames = 0; // true?
1963     s->low_delay = 1;
1964
1965     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1966     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1967
1968     if (avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
1969         s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
1970         if (avctx->idct_algo == FF_IDCT_AUTO)
1971             avctx->idct_algo = FF_IDCT_SIMPLE;
1972
1973     if (ff_MPV_common_init(s) < 0)
1974         return -1;
1975     exchange_uv(s); // common init reset pblocks, so we swap them here
1976     s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
1977     s1->mpeg_enc_ctx_allocated = 1;
1978
1979     for (i = 0; i < 64; i++) {
1980         int j = s->dsp.idct_permutation[i];
1981         v = ff_mpeg1_default_intra_matrix[i];
1982         s->intra_matrix[j]        = v;
1983         s->chroma_intra_matrix[j] = v;
1984
1985         v = ff_mpeg1_default_non_intra_matrix[i];
1986         s->inter_matrix[j]        = v;
1987         s->chroma_inter_matrix[j] = v;
1988     }
1989
1990     s->progressive_sequence  = 1;
1991     s->progressive_frame     = 1;
1992     s->picture_structure     = PICT_FRAME;
1993     s->frame_pred_frame_dct  = 1;
1994     s->chroma_format         = 1;
1995     s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1996     s1->save_width           = s->width;
1997     s1->save_height          = s->height;
1998     s1->save_progressive_seq = s->progressive_sequence;
1999     return 0;
2000 }
2001
2002
2003 static void mpeg_decode_user_data(AVCodecContext *avctx,
2004                                   const uint8_t *p, int buf_size)
2005 {
2006     const uint8_t *buf_end = p + buf_size;
2007
2008     /* we parse the DTG active format information */
2009     if (buf_end - p >= 5 &&
2010         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2011         int flags = p[4];
2012         p += 5;
2013         if (flags & 0x80) {
2014             /* skip event id */
2015             p += 2;
2016         }
2017         if (flags & 0x40) {
2018             if (buf_end - p < 1)
2019                 return;
2020             avctx->dtg_active_format = p[0] & 0x0f;
2021         }
2022     }
2023 }
2024
2025 static void mpeg_decode_gop(AVCodecContext *avctx,
2026                             const uint8_t *buf, int buf_size)
2027 {
2028     Mpeg1Context *s1  = avctx->priv_data;
2029     MpegEncContext *s = &s1->mpeg_enc_ctx;
2030
2031     int time_code_hours, time_code_minutes;
2032     int time_code_seconds, time_code_pictures;
2033     int broken_link;
2034
2035     init_get_bits(&s->gb, buf, buf_size*8);
2036
2037     skip_bits1(&s->gb); /* drop_frame_flag */
2038
2039     time_code_hours   = get_bits(&s->gb, 5);
2040     time_code_minutes = get_bits(&s->gb, 6);
2041     skip_bits1(&s->gb); // marker bit
2042     time_code_seconds  = get_bits(&s->gb, 6);
2043     time_code_pictures = get_bits(&s->gb, 6);
2044
2045     s1->closed_gop = get_bits1(&s->gb);
2046     /*broken_link indicate that after editing the
2047       reference frames of the first B-Frames after GOP I-Frame
2048       are missing (open gop)*/
2049     broken_link = get_bits1(&s->gb);
2050
2051     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2052         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2053                time_code_hours, time_code_minutes, time_code_seconds,
2054                time_code_pictures, s1->closed_gop, broken_link);
2055 }
2056
2057 static int decode_chunks(AVCodecContext *avctx,
2058                          AVFrame *picture, int *got_output,
2059                          const uint8_t *buf, int buf_size)
2060 {
2061     Mpeg1Context *s = avctx->priv_data;
2062     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2063     const uint8_t *buf_ptr = buf;
2064     const uint8_t *buf_end = buf + buf_size;
2065     int ret, input_size;
2066     int last_code = 0;
2067
2068     for (;;) {
2069         /* find next start code */
2070         uint32_t start_code = -1;
2071         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2072         if (start_code > 0x1ff) {
2073             if (s2->pict_type != AV_PICTURE_TYPE_B || avctx->skip_frame <= AVDISCARD_DEFAULT) {
2074                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2075                     int i;
2076
2077                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
2078                     for (i = 0; i < s->slice_count; i++)
2079                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2080                 }
2081
2082                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2083                     && avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
2084                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2085
2086                 ret = slice_end(avctx, picture);
2087                 if (ret < 0)
2088                     return ret;
2089                 else if (ret) {
2090                     if (s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2091                         *got_output = 1;
2092                 }
2093             }
2094             s2->pict_type = 0;
2095             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2096         }
2097
2098         input_size = buf_end - buf_ptr;
2099
2100         if (avctx->debug & FF_DEBUG_STARTCODE) {
2101             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2102         }
2103
2104         /* prepare data for next start code */
2105         switch (start_code) {
2106         case SEQ_START_CODE:
2107             if (last_code == 0) {
2108                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2109                 s->sync=1;
2110             } else {
2111                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
2112                 if (avctx->err_recognition & AV_EF_EXPLODE)
2113                     return AVERROR_INVALIDDATA;
2114             }
2115             break;
2116
2117         case PICTURE_START_CODE:
2118             if (s2->width <= 0 || s2->height <= 0) {
2119                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2120                        s2->width, s2->height);
2121                 return AVERROR_INVALIDDATA;
2122             }
2123
2124             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && s->slice_count) {
2125                 int i;
2126
2127                 avctx->execute(avctx, slice_decode_thread,
2128                                s2->thread_context, NULL,
2129                                s->slice_count, sizeof(void*));
2130                 for (i = 0; i < s->slice_count; i++)
2131                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2132                 s->slice_count = 0;
2133             }
2134             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2135                 ret = mpeg_decode_postinit(avctx);
2136                 if (ret < 0) {
2137                     av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
2138                     return ret;
2139                 }
2140
2141                 /* we have a complete image: we try to decompress it */
2142                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2143                     s2->pict_type = 0;
2144                 s2->first_slice = 1;
2145                 last_code = PICTURE_START_CODE;
2146             } else {
2147                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
2148                 if (avctx->err_recognition & AV_EF_EXPLODE)
2149                     return AVERROR_INVALIDDATA;
2150             }
2151             break;
2152         case EXT_START_CODE:
2153             init_get_bits(&s2->gb, buf_ptr, input_size*8);
2154
2155             switch (get_bits(&s2->gb, 4)) {
2156             case 0x1:
2157                 if (last_code == 0) {
2158                 mpeg_decode_sequence_extension(s);
2159                 } else {
2160                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
2161                     if (avctx->err_recognition & AV_EF_EXPLODE)
2162                         return AVERROR_INVALIDDATA;
2163                 }
2164                 break;
2165             case 0x2:
2166                 mpeg_decode_sequence_display_extension(s);
2167                 break;
2168             case 0x3:
2169                 mpeg_decode_quant_matrix_extension(s2);
2170                 break;
2171             case 0x7:
2172                 mpeg_decode_picture_display_extension(s);
2173                 break;
2174             case 0x8:
2175                 if (last_code == PICTURE_START_CODE) {
2176                     mpeg_decode_picture_coding_extension(s);
2177                 } else {
2178                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
2179                     if (avctx->err_recognition & AV_EF_EXPLODE)
2180                         return AVERROR_INVALIDDATA;
2181                 }
2182                 break;
2183             }
2184             break;
2185         case USER_START_CODE:
2186             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2187             break;
2188         case GOP_START_CODE:
2189             if (last_code == 0) {
2190                 s2->first_field=0;
2191                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2192                 s->sync=1;
2193             } else {
2194                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
2195                 if (avctx->err_recognition & AV_EF_EXPLODE)
2196                     return AVERROR_INVALIDDATA;
2197             }
2198             break;
2199         default:
2200             if (start_code >= SLICE_MIN_START_CODE &&
2201                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2202                 const int field_pic = s2->picture_structure != PICT_FRAME;
2203                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
2204                 last_code = SLICE_MIN_START_CODE;
2205
2206                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2207                     mb_y++;
2208
2209                 if (mb_y >= s2->mb_height) {
2210                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2211                     return -1;
2212                 }
2213
2214                 if (s2->last_picture_ptr == NULL) {
2215                 /* Skip B-frames if we do not have reference frames and gop is not closed */
2216                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2217                         if (!s->closed_gop)
2218                             break;
2219                     }
2220                 }
2221                 if (s2->pict_type == AV_PICTURE_TYPE_I)
2222                     s->sync=1;
2223                 if (s2->next_picture_ptr == NULL) {
2224                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2225                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) break;
2226                 }
2227                 if ((avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type == AV_PICTURE_TYPE_B) ||
2228                     (avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type != AV_PICTURE_TYPE_I) ||
2229                      avctx->skip_frame >= AVDISCARD_ALL)
2230                     break;
2231
2232                 if (!s->mpeg_enc_ctx_allocated)
2233                     break;
2234
2235                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2236                     if (mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2237                         break;
2238                 }
2239
2240                 if (!s2->pict_type) {
2241                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2242                     if (avctx->err_recognition & AV_EF_EXPLODE)
2243                         return AVERROR_INVALIDDATA;
2244                     break;
2245                 }
2246
2247                 if (s2->first_slice) {
2248                     s2->first_slice = 0;
2249                     if (mpeg_field_start(s2, buf, buf_size) < 0)
2250                         return -1;
2251                 }
2252                 if (!s2->current_picture_ptr) {
2253                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2254                     return AVERROR_INVALIDDATA;
2255                 }
2256
2257                 if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
2258                     s->slice_count++;
2259                     break;
2260                 }
2261
2262                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2263                     int threshold = (s2->mb_height * s->slice_count +
2264                                      s2->slice_context_count / 2) /
2265                                     s2->slice_context_count;
2266                     if (threshold <= mb_y) {
2267                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2268
2269                         thread_context->start_mb_y = mb_y;
2270                         thread_context->end_mb_y   = s2->mb_height;
2271                         if (s->slice_count) {
2272                             s2->thread_context[s->slice_count-1]->end_mb_y = mb_y;
2273                             ret = ff_update_duplicate_context(thread_context,
2274                                                               s2);
2275                             if (ret < 0)
2276                                 return ret;
2277                         }
2278                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2279                         s->slice_count++;
2280                     }
2281                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2282                 } else {
2283                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2284                     emms_c();
2285
2286                     if (ret < 0) {
2287                         if (avctx->err_recognition & AV_EF_EXPLODE)
2288                             return ret;
2289                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2290                             ff_er_add_slice(&s2->er, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2291                     } else {
2292                         ff_er_add_slice(&s2->er, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
2293                     }
2294                 }
2295             }
2296             break;
2297         }
2298     }
2299 }
2300
2301 static int mpeg_decode_frame(AVCodecContext *avctx,
2302                              void *data, int *got_output,
2303                              AVPacket *avpkt)
2304 {
2305     const uint8_t *buf = avpkt->data;
2306     int buf_size = avpkt->size;
2307     Mpeg1Context *s = avctx->priv_data;
2308     AVFrame *picture = data;
2309     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2310     av_dlog(avctx, "fill_buffer\n");
2311
2312     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2313         /* special case for last picture */
2314         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2315             int ret = av_frame_ref(picture, &s2->next_picture_ptr->f);
2316             if (ret < 0)
2317                 return ret;
2318
2319             s2->next_picture_ptr = NULL;
2320
2321             *got_output = 1;
2322         }
2323         return buf_size;
2324     }
2325
2326     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2327         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
2328
2329         if (ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0)
2330             return buf_size;
2331     }
2332
2333     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
2334         vcr2_init_sequence(avctx);
2335
2336     s->slice_count = 0;
2337
2338     if (avctx->extradata && !s->extradata_decoded) {
2339         int ret = decode_chunks(avctx, picture, got_output, avctx->extradata, avctx->extradata_size);
2340         s->extradata_decoded = 1;
2341         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2342             return ret;
2343     }
2344
2345     return decode_chunks(avctx, picture, got_output, buf, buf_size);
2346 }
2347
2348
2349 static void flush(AVCodecContext *avctx)
2350 {
2351     Mpeg1Context *s = avctx->priv_data;
2352
2353     s->sync=0;
2354     s->closed_gop = 0;
2355
2356     ff_mpeg_flush(avctx);
2357 }
2358
2359 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2360 {
2361     Mpeg1Context *s = avctx->priv_data;
2362
2363     if (s->mpeg_enc_ctx_allocated)
2364         ff_MPV_common_end(&s->mpeg_enc_ctx);
2365     return 0;
2366 }
2367
2368 static const AVProfile mpeg2_video_profiles[] = {
2369     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2370     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2371     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2372     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2373     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2374     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2375     { FF_PROFILE_RESERVED,           "Reserved"           },
2376     { FF_PROFILE_RESERVED,           "Reserved"           },
2377     { FF_PROFILE_UNKNOWN },
2378 };
2379
2380
2381 AVCodec ff_mpeg1video_decoder = {
2382     .name                  = "mpeg1video",
2383     .type                  = AVMEDIA_TYPE_VIDEO,
2384     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2385     .priv_data_size        = sizeof(Mpeg1Context),
2386     .init                  = mpeg_decode_init,
2387     .close                 = mpeg_decode_end,
2388     .decode                = mpeg_decode_frame,
2389     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2390                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2391                              CODEC_CAP_SLICE_THREADS,
2392     .flush                 = flush,
2393     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2394     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2395 };
2396
2397 AVCodec ff_mpeg2video_decoder = {
2398     .name           = "mpeg2video",
2399     .type           = AVMEDIA_TYPE_VIDEO,
2400     .id             = AV_CODEC_ID_MPEG2VIDEO,
2401     .priv_data_size = sizeof(Mpeg1Context),
2402     .init           = mpeg_decode_init,
2403     .close          = mpeg_decode_end,
2404     .decode         = mpeg_decode_frame,
2405     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2406                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2407                       CODEC_CAP_SLICE_THREADS,
2408     .flush          = flush,
2409     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2410     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2411 };
2412
2413 #if CONFIG_MPEG_XVMC_DECODER
2414 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2415 {
2416     if (avctx->active_thread_type & FF_THREAD_SLICE)
2417         return -1;
2418     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2419         return -1;
2420     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2421         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2422     }
2423     mpeg_decode_init(avctx);
2424
2425     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2426     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2427
2428     return 0;
2429 }
2430
2431 AVCodec ff_mpeg_xvmc_decoder = {
2432     .name           = "mpegvideo_xvmc",
2433     .type           = AVMEDIA_TYPE_VIDEO,
2434     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2435     .priv_data_size = sizeof(Mpeg1Context),
2436     .init           = mpeg_mc_decode_init,
2437     .close          = mpeg_decode_end,
2438     .decode         = mpeg_decode_frame,
2439     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2440                       CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2441     .flush          = flush,
2442     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2443 };
2444
2445 #endif
2446
2447 #if CONFIG_MPEG_VDPAU_DECODER
2448 AVCodec ff_mpeg_vdpau_decoder = {
2449     .name           = "mpegvideo_vdpau",
2450     .type           = AVMEDIA_TYPE_VIDEO,
2451     .id             = AV_CODEC_ID_MPEG2VIDEO,
2452     .priv_data_size = sizeof(Mpeg1Context),
2453     .init           = mpeg_decode_init,
2454     .close          = mpeg_decode_end,
2455     .decode         = mpeg_decode_frame,
2456     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2457                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2458     .flush          = flush,
2459     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2460 };
2461 #endif
2462
2463 #if CONFIG_MPEG1_VDPAU_DECODER
2464 AVCodec ff_mpeg1_vdpau_decoder = {
2465     .name           = "mpeg1video_vdpau",
2466     .type           = AVMEDIA_TYPE_VIDEO,
2467     .id             = AV_CODEC_ID_MPEG1VIDEO,
2468     .priv_data_size = sizeof(Mpeg1Context),
2469     .init           = mpeg_decode_init,
2470     .close          = mpeg_decode_end,
2471     .decode         = mpeg_decode_frame,
2472     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2473                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2474     .flush          = flush,
2475     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2476 };
2477 #endif