libavcodec/mpeg12.c

   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 FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file libavcodec/mpeg12.c
  25  * MPEG-1/2 decoder
  26  */
  27
  28 //#define DEBUG
  29 #include "internal.h"
  30 #include "avcodec.h"
  31 #include "dsputil.h"
  32 #include "mpegvideo.h"
  33
  34 #include "mpeg12.h"
  35 #include "mpeg12data.h"
  36 #include "mpeg12decdata.h"
  37 #include "bytestream.h"
  38 #include "vdpau_internal.h"
  39 #include "xvmc_internal.h"
  40
  41 //#undef NDEBUG
  42 //#include <assert.h>
  43
  44
  45 #define MV_VLC_BITS 9
  46 #define MBINCR_VLC_BITS 9
  47 #define MB_PAT_VLC_BITS 9
  48 #define MB_PTYPE_VLC_BITS 6
  49 #define MB_BTYPE_VLC_BITS 6
  50
  51 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
  52                               DCTELEM *block,
  53                               int n);
  54 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
  55 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
  56                                         DCTELEM *block,
  57                                         int n);
  58 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
  59                                     DCTELEM *block,
  60                                     int n);
  61 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
  62 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
  63 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
  64 static void exchange_uv(MpegEncContext *s);
  65
  66 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
  67                                            PIX_FMT_XVMC_MPEG2_IDCT,
  68                                            PIX_FMT_XVMC_MPEG2_MC,
  69                                            PIX_FMT_NONE};
  70
  71 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
  72
  73
  74 #define INIT_2D_VLC_RL(rl, static_size)\
  75 {\
  76     static RL_VLC_ELEM rl_vlc_table[static_size];\
  77     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
  78              &rl.table_vlc[0][1], 4, 2,\
  79              &rl.table_vlc[0][0], 4, 2, static_size);\
  80 \
  81     rl.rl_vlc[0]= rl_vlc_table;\
  82     init_2d_vlc_rl(&rl);\
  83 }
  84
  85 static void init_2d_vlc_rl(RLTable *rl)
  86 {
  87     int i;
  88
  89     for(i=0; i<rl->vlc.table_size; i++){
  90         int code= rl->vlc.table[i][0];
  91         int len = rl->vlc.table[i][1];
  92         int level, run;
  93
  94         if(len==0){ // illegal code
  95             run= 65;
  96             level= MAX_LEVEL;
  97         }else if(len<0){ //more bits needed
  98             run= 0;
  99             level= code;
 100         }else{
 101             if(code==rl->n){ //esc
 102                 run= 65;
 103                 level= 0;
 104             }else if(code==rl->n+1){ //eob
 105                 run= 0;
 106                 level= 127;
 107             }else{
 108                 run=   rl->table_run  [code] + 1;
 109                 level= rl->table_level[code];
 110             }
 111         }
 112         rl->rl_vlc[0][i].len= len;
 113         rl->rl_vlc[0][i].level= level;
 114         rl->rl_vlc[0][i].run= run;
 115     }
 116 }
 117
 118 void ff_mpeg12_common_init(MpegEncContext *s)
 119 {
 120
 121     s->y_dc_scale_table=
 122     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
 123
 124 }
 125
 126 void ff_mpeg1_clean_buffers(MpegEncContext *s){
 127     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
 128     s->last_dc[1] = s->last_dc[0];
 129     s->last_dc[2] = s->last_dc[0];
 130     memset(s->last_mv, 0, sizeof(s->last_mv));
 131 }
 132
 133
 134 /******************************************/
 135 /* decoding */
 136
 137 static VLC mv_vlc;
 138 static VLC mbincr_vlc;
 139 static VLC mb_ptype_vlc;
 140 static VLC mb_btype_vlc;
 141 static VLC mb_pat_vlc;
 142
 143 av_cold void ff_mpeg12_init_vlcs(void)
 144 {
 145     static int done = 0;
 146
 147     if (!done) {
 148         done = 1;
 149
 150         INIT_VLC_STATIC(&dc_lum_vlc, DC_VLC_BITS, 12,
 151                  ff_mpeg12_vlc_dc_lum_bits, 1, 1,
 152                  ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
 153         INIT_VLC_STATIC(&dc_chroma_vlc,  DC_VLC_BITS, 12,
 154                  ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
 155                  ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
 156         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
 157                  &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
 158                  &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
 159         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
 160                  &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
 161                  &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
 162         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
 163                  &ff_mpeg12_mbPatTable[0][1], 2, 1,
 164                  &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
 165
 166         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
 167                  &table_mb_ptype[0][1], 2, 1,
 168                  &table_mb_ptype[0][0], 2, 1, 64);
 169         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
 170                  &table_mb_btype[0][1], 2, 1,
 171                  &table_mb_btype[0][0], 2, 1, 64);
 172         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
 173         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
 174
 175         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
 176         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
 177     }
 178 }
 179
 180 static inline int get_dmv(MpegEncContext *s)
 181 {
 182     if(get_bits1(&s->gb))
 183         return 1 - (get_bits1(&s->gb) << 1);
 184     else
 185         return 0;
 186 }
 187
 188 static inline int get_qscale(MpegEncContext *s)
 189 {
 190     int qscale = get_bits(&s->gb, 5);
 191     if (s->q_scale_type) {
 192         return non_linear_qscale[qscale];
 193     } else {
 194         return qscale << 1;
 195     }
 196 }
 197
 198 /* motion type (for MPEG-2) */
 199 #define MT_FIELD 1
 200 #define MT_FRAME 2
 201 #define MT_16X8  2
 202 #define MT_DMV   3
 203
 204 static int mpeg_decode_mb(MpegEncContext *s,
 205                           DCTELEM block[12][64])
 206 {
 207     int i, j, k, cbp, val, mb_type, motion_type;
 208     const int mb_block_count = 4 + (1<< s->chroma_format);
 209
 210     dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 211
 212     assert(s->mb_skipped==0);
 213
 214     if (s->mb_skip_run-- != 0) {
 215         if (s->pict_type == FF_P_TYPE) {
 216             s->mb_skipped = 1;
 217             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 218         } else {
 219             int mb_type;
 220
 221             if(s->mb_x)
 222                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
 223             else
 224                 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
 225             if(IS_INTRA(mb_type))
 226                 return -1;
 227
 228             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
 229                 mb_type | MB_TYPE_SKIP;
 230 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
 231
 232             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
 233                 s->mb_skipped = 1;
 234         }
 235
 236         return 0;
 237     }
 238
 239     switch(s->pict_type) {
 240     default:
 241     case FF_I_TYPE:
 242         if (get_bits1(&s->gb) == 0) {
 243             if (get_bits1(&s->gb) == 0){
 244                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
 245                 return -1;
 246             }
 247             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 248         } else {
 249             mb_type = MB_TYPE_INTRA;
 250         }
 251         break;
 252     case FF_P_TYPE:
 253         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 254         if (mb_type < 0){
 255             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 256             return -1;
 257         }
 258         mb_type = ptype2mb_type[ mb_type ];
 259         break;
 260     case FF_B_TYPE:
 261         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 262         if (mb_type < 0){
 263             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 264             return -1;
 265         }
 266         mb_type = btype2mb_type[ mb_type ];
 267         break;
 268     }
 269     dprintf(s->avctx, "mb_type=%x\n", mb_type);
 270 //    motion_type = 0; /* avoid warning */
 271     if (IS_INTRA(mb_type)) {
 272         s->dsp.clear_blocks(s->block[0]);
 273
 274         if(!s->chroma_y_shift){
 275             s->dsp.clear_blocks(s->block[6]);
 276         }
 277
 278         /* compute DCT type */
 279         if (s->picture_structure == PICT_FRAME && //FIXME add an interlaced_dct coded var?
 280             !s->frame_pred_frame_dct) {
 281             s->interlaced_dct = get_bits1(&s->gb);
 282         }
 283
 284         if (IS_QUANT(mb_type))
 285             s->qscale = get_qscale(s);
 286
 287         if (s->concealment_motion_vectors) {
 288             /* just parse them */
 289             if (s->picture_structure != PICT_FRAME)
 290                 skip_bits1(&s->gb); /* field select */
 291
 292             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 293                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 294             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 295                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 296
 297             skip_bits1(&s->gb); /* marker */
 298         }else
 299             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 300         s->mb_intra = 1;
 301         //if 1, we memcpy blocks in xvmcvideo
 302         if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1){
 303             ff_xvmc_pack_pblocks(s,-1);//inter are always full blocks
 304             if(s->swap_uv){
 305                 exchange_uv(s);
 306             }
 307         }
 308
 309         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 310             if(s->flags2 & CODEC_FLAG2_FAST){
 311                 for(i=0;i<6;i++) {
 312                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
 313                 }
 314             }else{
 315                 for(i=0;i<mb_block_count;i++) {
 316                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
 317                         return -1;
 318                 }
 319             }
 320         } else {
 321             for(i=0;i<6;i++) {
 322                 if (ff_mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
 323                     return -1;
 324             }
 325         }
 326     } else {
 327         if (mb_type & MB_TYPE_ZERO_MV){
 328             assert(mb_type & MB_TYPE_CBP);
 329
 330             s->mv_dir = MV_DIR_FORWARD;
 331             if(s->picture_structure == PICT_FRAME){
 332                 if(!s->frame_pred_frame_dct)
 333                     s->interlaced_dct = get_bits1(&s->gb);
 334                 s->mv_type = MV_TYPE_16X16;
 335             }else{
 336                 s->mv_type = MV_TYPE_FIELD;
 337                 mb_type |= MB_TYPE_INTERLACED;
 338                 s->field_select[0][0]= s->picture_structure - 1;
 339             }
 340
 341             if (IS_QUANT(mb_type))
 342                 s->qscale = get_qscale(s);
 343
 344             s->last_mv[0][0][0] = 0;
 345             s->last_mv[0][0][1] = 0;
 346             s->last_mv[0][1][0] = 0;
 347             s->last_mv[0][1][1] = 0;
 348             s->mv[0][0][0] = 0;
 349             s->mv[0][0][1] = 0;
 350         }else{
 351             assert(mb_type & MB_TYPE_L0L1);
 352 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 353             /* get additional motion vector type */
 354             if (s->frame_pred_frame_dct)
 355                 motion_type = MT_FRAME;
 356             else{
 357                 motion_type = get_bits(&s->gb, 2);
 358                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 359                     s->interlaced_dct = get_bits1(&s->gb);
 360             }
 361
 362             if (IS_QUANT(mb_type))
 363                 s->qscale = get_qscale(s);
 364
 365             /* motion vectors */
 366             s->mv_dir= (mb_type>>13)&3;
 367             dprintf(s->avctx, "motion_type=%d\n", motion_type);
 368             switch(motion_type) {
 369             case MT_FRAME: /* or MT_16X8 */
 370                 if (s->picture_structure == PICT_FRAME) {
 371                     mb_type |= MB_TYPE_16x16;
 372                     s->mv_type = MV_TYPE_16X16;
 373                     for(i=0;i<2;i++) {
 374                         if (USES_LIST(mb_type, i)) {
 375                             /* MT_FRAME */
 376                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
 377                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
 378                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
 379                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
 380                             /* full_pel: only for MPEG-1 */
 381                             if (s->full_pel[i]){
 382                                 s->mv[i][0][0] <<= 1;
 383                                 s->mv[i][0][1] <<= 1;
 384                             }
 385                         }
 386                     }
 387                 } else {
 388                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 389                     s->mv_type = MV_TYPE_16X8;
 390                     for(i=0;i<2;i++) {
 391                         if (USES_LIST(mb_type, i)) {
 392                             /* MT_16X8 */
 393                             for(j=0;j<2;j++) {
 394                                 s->field_select[i][j] = get_bits1(&s->gb);
 395                                 for(k=0;k<2;k++) {
 396                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 397                                                              s->last_mv[i][j][k]);
 398                                     s->last_mv[i][j][k] = val;
 399                                     s->mv[i][j][k] = val;
 400                                 }
 401                             }
 402                         }
 403                     }
 404                 }
 405                 break;
 406             case MT_FIELD:
 407                 s->mv_type = MV_TYPE_FIELD;
 408                 if (s->picture_structure == PICT_FRAME) {
 409                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 410                     for(i=0;i<2;i++) {
 411                         if (USES_LIST(mb_type, i)) {
 412                             for(j=0;j<2;j++) {
 413                                 s->field_select[i][j] = get_bits1(&s->gb);
 414                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 415                                                          s->last_mv[i][j][0]);
 416                                 s->last_mv[i][j][0] = val;
 417                                 s->mv[i][j][0] = val;
 418                                 dprintf(s->avctx, "fmx=%d\n", val);
 419                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 420                                                          s->last_mv[i][j][1] >> 1);
 421                                 s->last_mv[i][j][1] = val << 1;
 422                                 s->mv[i][j][1] = val;
 423                                 dprintf(s->avctx, "fmy=%d\n", val);
 424                             }
 425                         }
 426                     }
 427                 } else {
 428                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 429                     for(i=0;i<2;i++) {
 430                         if (USES_LIST(mb_type, i)) {
 431                             s->field_select[i][0] = get_bits1(&s->gb);
 432                             for(k=0;k<2;k++) {
 433                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 434                                                          s->last_mv[i][0][k]);
 435                                 s->last_mv[i][0][k] = val;
 436                                 s->last_mv[i][1][k] = val;
 437                                 s->mv[i][0][k] = val;
 438                             }
 439                         }
 440                     }
 441                 }
 442                 break;
 443             case MT_DMV:
 444                 s->mv_type = MV_TYPE_DMV;
 445                 for(i=0;i<2;i++) {
 446                     if (USES_LIST(mb_type, i)) {
 447                         int dmx, dmy, mx, my, m;
 448                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 449                                                 s->last_mv[i][0][0]);
 450                         s->last_mv[i][0][0] = mx;
 451                         s->last_mv[i][1][0] = mx;
 452                         dmx = get_dmv(s);
 453                         my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 454                                                 s->last_mv[i][0][1] >> 1);
 455                         dmy = get_dmv(s);
 456
 457
 458                         s->last_mv[i][0][1] = my<<1;
 459                         s->last_mv[i][1][1] = my<<1;
 460
 461                         s->mv[i][0][0] = mx;
 462                         s->mv[i][0][1] = my;
 463                         s->mv[i][1][0] = mx;//not used
 464                         s->mv[i][1][1] = my;//not used
 465
 466                         if (s->picture_structure == PICT_FRAME) {
 467                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 468
 469                             //m = 1 + 2 * s->top_field_first;
 470                             m = s->top_field_first ? 1 : 3;
 471
 472                             /* top -> top pred */
 473                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 474                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 475                             m = 4 - m;
 476                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 477                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 478                         } else {
 479                             mb_type |= MB_TYPE_16x16;
 480
 481                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 482                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 483                             if(s->picture_structure == PICT_TOP_FIELD)
 484                                 s->mv[i][2][1]--;
 485                             else
 486                                 s->mv[i][2][1]++;
 487                         }
 488                     }
 489                 }
 490                 break;
 491             default:
 492                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 493                 return -1;
 494             }
 495         }
 496
 497         s->mb_intra = 0;
 498         if (HAS_CBP(mb_type)) {
 499             s->dsp.clear_blocks(s->block[0]);
 500
 501             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 502             if(mb_block_count > 6){
 503                  cbp<<= mb_block_count-6;
 504                  cbp |= get_bits(&s->gb, mb_block_count-6);
 505                  s->dsp.clear_blocks(s->block[6]);
 506             }
 507             if (cbp <= 0){
 508                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
 509                 return -1;
 510             }
 511
 512             //if 1, we memcpy blocks in xvmcvideo
 513             if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1){
 514                 ff_xvmc_pack_pblocks(s,cbp);
 515                 if(s->swap_uv){
 516                     exchange_uv(s);
 517                 }
 518             }
 519
 520             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 521                 if(s->flags2 & CODEC_FLAG2_FAST){
 522                     for(i=0;i<6;i++) {
 523                         if(cbp & 32) {
 524                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
 525                         } else {
 526                             s->block_last_index[i] = -1;
 527                         }
 528                         cbp+=cbp;
 529                     }
 530                 }else{
 531                     cbp<<= 12-mb_block_count;
 532
 533                     for(i=0;i<mb_block_count;i++) {
 534                         if ( cbp & (1<<11) ) {
 535                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
 536                                 return -1;
 537                         } else {
 538                             s->block_last_index[i] = -1;
 539                         }
 540                         cbp+=cbp;
 541                     }
 542                 }
 543             } else {
 544                 if(s->flags2 & CODEC_FLAG2_FAST){
 545                     for(i=0;i<6;i++) {
 546                         if (cbp & 32) {
 547                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
 548                         } else {
 549                             s->block_last_index[i] = -1;
 550                         }
 551                         cbp+=cbp;
 552                     }
 553                 }else{
 554                     for(i=0;i<6;i++) {
 555                         if (cbp & 32) {
 556                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
 557                                 return -1;
 558                         } else {
 559                             s->block_last_index[i] = -1;
 560                         }
 561                         cbp+=cbp;
 562                     }
 563                 }
 564             }
 565         }else{
 566             for(i=0;i<12;i++)
 567                 s->block_last_index[i] = -1;
 568         }
 569     }
 570
 571     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
 572
 573     return 0;
 574 }
 575
 576 /* as H.263, but only 17 codes */
 577 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 578 {
 579     int code, sign, val, l, shift;
 580
 581     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
 582     if (code == 0) {
 583         return pred;
 584     }
 585     if (code < 0) {
 586         return 0xffff;
 587     }
 588
 589     sign = get_bits1(&s->gb);
 590     shift = fcode - 1;
 591     val = code;
 592     if (shift) {
 593         val = (val - 1) << shift;
 594         val |= get_bits(&s->gb, shift);
 595         val++;
 596     }
 597     if (sign)
 598         val = -val;
 599     val += pred;
 600
 601     /* modulo decoding */
 602     l= INT_BIT - 5 - shift;
 603     val = (val<<l)>>l;
 604     return val;
 605 }
 606
 607 inline int ff_mpeg1_decode_block_intra(MpegEncContext *s,
 608                                DCTELEM *block,
 609                                int n)
 610 {
 611     int level, dc, diff, i, j, run;
 612     int component;
 613     RLTable *rl = &ff_rl_mpeg1;
 614     uint8_t * const scantable= s->intra_scantable.permutated;
 615     const uint16_t *quant_matrix= s->intra_matrix;
 616     const int qscale= s->qscale;
 617
 618     /* DC coefficient */
 619     component = (n <= 3 ? 0 : n - 4 + 1);
 620     diff = decode_dc(&s->gb, component);
 621     if (diff >= 0xffff)
 622         return -1;
 623     dc = s->last_dc[component];
 624     dc += diff;
 625     s->last_dc[component] = dc;
 626     block[0] = dc*quant_matrix[0];
 627     dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
 628     i = 0;
 629     {
 630         OPEN_READER(re, &s->gb);
 631         /* now quantify & encode AC coefficients */
 632         for(;;) {
 633             UPDATE_CACHE(re, &s->gb);
 634             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 635
 636             if(level == 127){
 637                 break;
 638             } else if(level != 0) {
 639                 i += run;
 640                 j = scantable[i];
 641                 level= (level*qscale*quant_matrix[j])>>4;
 642                 level= (level-1)|1;
 643                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 644                 LAST_SKIP_BITS(re, &s->gb, 1);
 645             } else {
 646                 /* escape */
 647                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 648                 UPDATE_CACHE(re, &s->gb);
 649                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 650                 if (level == -128) {
 651                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
 652                 } else if (level == 0) {
 653                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
 654                 }
 655                 i += run;
 656                 j = scantable[i];
 657                 if(level<0){
 658                     level= -level;
 659                     level= (level*qscale*quant_matrix[j])>>4;
 660                     level= (level-1)|1;
 661                     level= -level;
 662                 }else{
 663                     level= (level*qscale*quant_matrix[j])>>4;
 664                     level= (level-1)|1;
 665                 }
 666             }
 667             if (i > 63){
 668                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 669                 return -1;
 670             }
 671
 672             block[j] = level;
 673         }
 674         CLOSE_READER(re, &s->gb);
 675     }
 676     s->block_last_index[n] = i;
 677    return 0;
 678 }
 679
 680 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 681                                DCTELEM *block,
 682                                int n)
 683 {
 684     int level, i, j, run;
 685     RLTable *rl = &ff_rl_mpeg1;
 686     uint8_t * const scantable= s->intra_scantable.permutated;
 687     const uint16_t *quant_matrix= s->inter_matrix;
 688     const int qscale= s->qscale;
 689
 690     {
 691         OPEN_READER(re, &s->gb);
 692         i = -1;
 693         // special case for first coefficient, no need to add second VLC table
 694         UPDATE_CACHE(re, &s->gb);
 695         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 696             level= (3*qscale*quant_matrix[0])>>5;
 697             level= (level-1)|1;
 698             if(GET_CACHE(re, &s->gb)&0x40000000)
 699                 level= -level;
 700             block[0] = level;
 701             i++;
 702             SKIP_BITS(re, &s->gb, 2);
 703             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 704                 goto end;
 705         }
 706 #if MIN_CACHE_BITS < 19
 707         UPDATE_CACHE(re, &s->gb);
 708 #endif
 709         /* now quantify & encode AC coefficients */
 710         for(;;) {
 711             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 712
 713             if(level != 0) {
 714                 i += run;
 715                 j = scantable[i];
 716                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 717                 level= (level-1)|1;
 718                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 719                 SKIP_BITS(re, &s->gb, 1);
 720             } else {
 721                 /* escape */
 722                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 723                 UPDATE_CACHE(re, &s->gb);
 724                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 725                 if (level == -128) {
 726                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 727                 } else if (level == 0) {
 728                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 729                 }
 730                 i += run;
 731                 j = scantable[i];
 732                 if(level<0){
 733                     level= -level;
 734                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 735                     level= (level-1)|1;
 736                     level= -level;
 737                 }else{
 738                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 739                     level= (level-1)|1;
 740                 }
 741             }
 742             if (i > 63){
 743                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 744                 return -1;
 745             }
 746
 747             block[j] = level;
 748 #if MIN_CACHE_BITS < 19
 749             UPDATE_CACHE(re, &s->gb);
 750 #endif
 751             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 752                 break;
 753 #if MIN_CACHE_BITS >= 19
 754             UPDATE_CACHE(re, &s->gb);
 755 #endif
 756         }
 757 end:
 758         LAST_SKIP_BITS(re, &s->gb, 2);
 759         CLOSE_READER(re, &s->gb);
 760     }
 761     s->block_last_index[n] = i;
 762     return 0;
 763 }
 764
 765 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
 766 {
 767     int level, i, j, run;
 768     RLTable *rl = &ff_rl_mpeg1;
 769     uint8_t * const scantable= s->intra_scantable.permutated;
 770     const int qscale= s->qscale;
 771
 772     {
 773         OPEN_READER(re, &s->gb);
 774         i = -1;
 775         // special case for first coefficient, no need to add second VLC table
 776         UPDATE_CACHE(re, &s->gb);
 777         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 778             level= (3*qscale)>>1;
 779             level= (level-1)|1;
 780             if(GET_CACHE(re, &s->gb)&0x40000000)
 781                 level= -level;
 782             block[0] = level;
 783             i++;
 784             SKIP_BITS(re, &s->gb, 2);
 785             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 786                 goto end;
 787         }
 788 #if MIN_CACHE_BITS < 19
 789         UPDATE_CACHE(re, &s->gb);
 790 #endif
 791
 792         /* now quantify & encode AC coefficients */
 793         for(;;) {
 794             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 795
 796             if(level != 0) {
 797                 i += run;
 798                 j = scantable[i];
 799                 level= ((level*2+1)*qscale)>>1;
 800                 level= (level-1)|1;
 801                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 802                 SKIP_BITS(re, &s->gb, 1);
 803             } else {
 804                 /* escape */
 805                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 806                 UPDATE_CACHE(re, &s->gb);
 807                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 808                 if (level == -128) {
 809                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 810                 } else if (level == 0) {
 811                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 812                 }
 813                 i += run;
 814                 j = scantable[i];
 815                 if(level<0){
 816                     level= -level;
 817                     level= ((level*2+1)*qscale)>>1;
 818                     level= (level-1)|1;
 819                     level= -level;
 820                 }else{
 821                     level= ((level*2+1)*qscale)>>1;
 822                     level= (level-1)|1;
 823                 }
 824             }
 825
 826             block[j] = level;
 827 #if MIN_CACHE_BITS < 19
 828             UPDATE_CACHE(re, &s->gb);
 829 #endif
 830             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 831                 break;
 832 #if MIN_CACHE_BITS >= 19
 833             UPDATE_CACHE(re, &s->gb);
 834 #endif
 835         }
 836 end:
 837         LAST_SKIP_BITS(re, &s->gb, 2);
 838         CLOSE_READER(re, &s->gb);
 839     }
 840     s->block_last_index[n] = i;
 841     return 0;
 842 }
 843
 844
 845 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 846                                DCTELEM *block,
 847                                int n)
 848 {
 849     int level, i, j, run;
 850     RLTable *rl = &ff_rl_mpeg1;
 851     uint8_t * const scantable= s->intra_scantable.permutated;
 852     const uint16_t *quant_matrix;
 853     const int qscale= s->qscale;
 854     int mismatch;
 855
 856     mismatch = 1;
 857
 858     {
 859         OPEN_READER(re, &s->gb);
 860         i = -1;
 861         if (n < 4)
 862             quant_matrix = s->inter_matrix;
 863         else
 864             quant_matrix = s->chroma_inter_matrix;
 865
 866         // special case for first coefficient, no need to add second VLC table
 867         UPDATE_CACHE(re, &s->gb);
 868         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 869             level= (3*qscale*quant_matrix[0])>>5;
 870             if(GET_CACHE(re, &s->gb)&0x40000000)
 871                 level= -level;
 872             block[0] = level;
 873             mismatch ^= level;
 874             i++;
 875             SKIP_BITS(re, &s->gb, 2);
 876             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 877                 goto end;
 878         }
 879 #if MIN_CACHE_BITS < 19
 880         UPDATE_CACHE(re, &s->gb);
 881 #endif
 882
 883         /* now quantify & encode AC coefficients */
 884         for(;;) {
 885             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 886
 887             if(level != 0) {
 888                 i += run;
 889                 j = scantable[i];
 890                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 891                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 892                 SKIP_BITS(re, &s->gb, 1);
 893             } else {
 894                 /* escape */
 895                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 896                 UPDATE_CACHE(re, &s->gb);
 897                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 898
 899                 i += run;
 900                 j = scantable[i];
 901                 if(level<0){
 902                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
 903                     level= -level;
 904                 }else{
 905                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 906                 }
 907             }
 908             if (i > 63){
 909                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 910                 return -1;
 911             }
 912
 913             mismatch ^= level;
 914             block[j] = level;
 915 #if MIN_CACHE_BITS < 19
 916             UPDATE_CACHE(re, &s->gb);
 917 #endif
 918             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 919                 break;
 920 #if MIN_CACHE_BITS >= 19
 921             UPDATE_CACHE(re, &s->gb);
 922 #endif
 923         }
 924 end:
 925         LAST_SKIP_BITS(re, &s->gb, 2);
 926         CLOSE_READER(re, &s->gb);
 927     }
 928     block[63] ^= (mismatch & 1);
 929
 930     s->block_last_index[n] = i;
 931     return 0;
 932 }
 933
 934 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 935                                DCTELEM *block,
 936                                int n)
 937 {
 938     int level, i, j, run;
 939     RLTable *rl = &ff_rl_mpeg1;
 940     uint8_t * const scantable= s->intra_scantable.permutated;
 941     const int qscale= s->qscale;
 942     OPEN_READER(re, &s->gb);
 943     i = -1;
 944
 945     // special case for first coefficient, no need to add second VLC table
 946     UPDATE_CACHE(re, &s->gb);
 947     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 948         level= (3*qscale)>>1;
 949         if(GET_CACHE(re, &s->gb)&0x40000000)
 950             level= -level;
 951         block[0] = level;
 952         i++;
 953         SKIP_BITS(re, &s->gb, 2);
 954         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 955             goto end;
 956     }
 957 #if MIN_CACHE_BITS < 19
 958     UPDATE_CACHE(re, &s->gb);
 959 #endif
 960
 961     /* now quantify & encode AC coefficients */
 962     for(;;) {
 963         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 964
 965         if(level != 0) {
 966             i += run;
 967             j = scantable[i];
 968             level= ((level*2+1)*qscale)>>1;
 969             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 970             SKIP_BITS(re, &s->gb, 1);
 971         } else {
 972             /* escape */
 973             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 974             UPDATE_CACHE(re, &s->gb);
 975             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 976
 977             i += run;
 978             j = scantable[i];
 979             if(level<0){
 980                 level= ((-level*2+1)*qscale)>>1;
 981                 level= -level;
 982             }else{
 983                 level= ((level*2+1)*qscale)>>1;
 984             }
 985         }
 986
 987         block[j] = level;
 988 #if MIN_CACHE_BITS < 19
 989         UPDATE_CACHE(re, &s->gb);
 990 #endif
 991         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 992             break;
 993 #if MIN_CACHE_BITS >=19
 994         UPDATE_CACHE(re, &s->gb);
 995 #endif
 996     }
 997 end:
 998     LAST_SKIP_BITS(re, &s->gb, 2);
 999     CLOSE_READER(re, &s->gb);
1000     s->block_last_index[n] = i;
1001     return 0;
1002 }
1003
1004
1005 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1006                                DCTELEM *block,
1007                                int n)
1008 {
1009     int level, dc, diff, i, j, run;
1010     int component;
1011     RLTable *rl;
1012     uint8_t * const scantable= s->intra_scantable.permutated;
1013     const uint16_t *quant_matrix;
1014     const int qscale= s->qscale;
1015     int mismatch;
1016
1017     /* DC coefficient */
1018     if (n < 4){
1019         quant_matrix = s->intra_matrix;
1020         component = 0;
1021     }else{
1022         quant_matrix = s->chroma_intra_matrix;
1023         component = (n&1) + 1;
1024     }
1025     diff = decode_dc(&s->gb, component);
1026     if (diff >= 0xffff)
1027         return -1;
1028     dc = s->last_dc[component];
1029     dc += diff;
1030     s->last_dc[component] = dc;
1031     block[0] = dc << (3 - s->intra_dc_precision);
1032     dprintf(s->avctx, "dc=%d\n", block[0]);
1033     mismatch = block[0] ^ 1;
1034     i = 0;
1035     if (s->intra_vlc_format)
1036         rl = &ff_rl_mpeg2;
1037     else
1038         rl = &ff_rl_mpeg1;
1039
1040     {
1041         OPEN_READER(re, &s->gb);
1042         /* now quantify & encode AC coefficients */
1043         for(;;) {
1044             UPDATE_CACHE(re, &s->gb);
1045             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1046
1047             if(level == 127){
1048                 break;
1049             } else if(level != 0) {
1050                 i += run;
1051                 j = scantable[i];
1052                 level= (level*qscale*quant_matrix[j])>>4;
1053                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1054                 LAST_SKIP_BITS(re, &s->gb, 1);
1055             } else {
1056                 /* escape */
1057                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1058                 UPDATE_CACHE(re, &s->gb);
1059                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1060                 i += run;
1061                 j = scantable[i];
1062                 if(level<0){
1063                     level= (-level*qscale*quant_matrix[j])>>4;
1064                     level= -level;
1065                 }else{
1066                     level= (level*qscale*quant_matrix[j])>>4;
1067                 }
1068             }
1069             if (i > 63){
1070                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1071                 return -1;
1072             }
1073
1074             mismatch^= level;
1075             block[j] = level;
1076         }
1077         CLOSE_READER(re, &s->gb);
1078     }
1079     block[63]^= mismatch&1;
1080
1081     s->block_last_index[n] = i;
1082     return 0;
1083 }
1084
1085 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1086                                DCTELEM *block,
1087                                int n)
1088 {
1089     int level, dc, diff, j, run;
1090     int component;
1091     RLTable *rl;
1092     uint8_t * scantable= s->intra_scantable.permutated;
1093     const uint16_t *quant_matrix;
1094     const int qscale= s->qscale;
1095
1096     /* DC coefficient */
1097     if (n < 4){
1098         quant_matrix = s->intra_matrix;
1099         component = 0;
1100     }else{
1101         quant_matrix = s->chroma_intra_matrix;
1102         component = (n&1) + 1;
1103     }
1104     diff = decode_dc(&s->gb, component);
1105     if (diff >= 0xffff)
1106         return -1;
1107     dc = s->last_dc[component];
1108     dc += diff;
1109     s->last_dc[component] = dc;
1110     block[0] = dc << (3 - s->intra_dc_precision);
1111     if (s->intra_vlc_format)
1112         rl = &ff_rl_mpeg2;
1113     else
1114         rl = &ff_rl_mpeg1;
1115
1116     {
1117         OPEN_READER(re, &s->gb);
1118         /* now quantify & encode AC coefficients */
1119         for(;;) {
1120             UPDATE_CACHE(re, &s->gb);
1121             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1122
1123             if(level == 127){
1124                 break;
1125             } else if(level != 0) {
1126                 scantable += run;
1127                 j = *scantable;
1128                 level= (level*qscale*quant_matrix[j])>>4;
1129                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1130                 LAST_SKIP_BITS(re, &s->gb, 1);
1131             } else {
1132                 /* escape */
1133                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1134                 UPDATE_CACHE(re, &s->gb);
1135                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1136                 scantable += run;
1137                 j = *scantable;
1138                 if(level<0){
1139                     level= (-level*qscale*quant_matrix[j])>>4;
1140                     level= -level;
1141                 }else{
1142                     level= (level*qscale*quant_matrix[j])>>4;
1143                 }
1144             }
1145
1146             block[j] = level;
1147         }
1148         CLOSE_READER(re, &s->gb);
1149     }
1150
1151     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1152     return 0;
1153 }
1154
1155 typedef struct Mpeg1Context {
1156     MpegEncContext mpeg_enc_ctx;
1157     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1158     int repeat_field; /* true if we must repeat the field */
1159     AVPanScan pan_scan; /** some temporary storage for the panscan */
1160     int slice_count;
1161     int swap_uv;//indicate VCR2
1162     int save_aspect_info;
1163     int save_width, save_height, save_progressive_seq;
1164     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1165
1166 } Mpeg1Context;
1167
1168 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1169 {
1170     Mpeg1Context *s = avctx->priv_data;
1171     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1172     int i;
1173
1174     /* we need some permutation to store matrices,
1175      * until MPV_common_init() sets the real permutation. */
1176     for(i=0;i<64;i++)
1177        s2->dsp.idct_permutation[i]=i;
1178
1179     MPV_decode_defaults(s2);
1180
1181     s->mpeg_enc_ctx.avctx= avctx;
1182     s->mpeg_enc_ctx.flags= avctx->flags;
1183     s->mpeg_enc_ctx.flags2= avctx->flags2;
1184     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1185     ff_mpeg12_init_vlcs();
1186
1187     s->mpeg_enc_ctx_allocated = 0;
1188     s->mpeg_enc_ctx.picture_number = 0;
1189     s->repeat_field = 0;
1190     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1191     return 0;
1192 }
1193
1194 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1195                                      const uint8_t *new_perm){
1196     uint16_t temp_matrix[64];
1197     int i;
1198
1199     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1200
1201     for(i=0;i<64;i++){
1202         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1203     }
1204 }
1205
1206 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx){
1207     Mpeg1Context *s1 = avctx->priv_data;
1208     MpegEncContext *s = &s1->mpeg_enc_ctx;
1209
1210     if(avctx->xvmc_acceleration)
1211         return avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1212     else if(avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU){
1213         if(avctx->codec_id == CODEC_ID_MPEG1VIDEO)
1214             return PIX_FMT_VDPAU_MPEG1;
1215         else
1216             return PIX_FMT_VDPAU_MPEG2;
1217     }else{
1218         if(s->chroma_format <  2)
1219             return avctx->get_format(avctx,ff_hwaccel_pixfmt_list_420);
1220         else if(s->chroma_format == 2)
1221             return PIX_FMT_YUV422P;
1222         else
1223             return PIX_FMT_YUV444P;
1224     }
1225 }
1226
1227 /* Call this function when we know all parameters.
1228  * It may be called in different places for MPEG-1 and MPEG-2. */
1229 static int mpeg_decode_postinit(AVCodecContext *avctx){
1230     Mpeg1Context *s1 = avctx->priv_data;
1231     MpegEncContext *s = &s1->mpeg_enc_ctx;
1232     uint8_t old_permutation[64];
1233
1234     if (
1235         (s1->mpeg_enc_ctx_allocated == 0)||
1236         avctx->coded_width  != s->width ||
1237         avctx->coded_height != s->height||
1238         s1->save_width != s->width ||
1239         s1->save_height != s->height ||
1240         s1->save_aspect_info != s->aspect_ratio_info||
1241         s1->save_progressive_seq != s->progressive_sequence ||
1242         0)
1243     {
1244
1245         if (s1->mpeg_enc_ctx_allocated) {
1246             ParseContext pc= s->parse_context;
1247             s->parse_context.buffer=0;
1248             MPV_common_end(s);
1249             s->parse_context= pc;
1250         }
1251
1252         if( (s->width == 0 )||(s->height == 0))
1253             return -2;
1254
1255         avcodec_set_dimensions(avctx, s->width, s->height);
1256         avctx->bit_rate = s->bit_rate;
1257         s1->save_aspect_info = s->aspect_ratio_info;
1258         s1->save_width = s->width;
1259         s1->save_height = s->height;
1260         s1->save_progressive_seq = s->progressive_sequence;
1261
1262         /* low_delay may be forced, in this case we will have B-frames
1263          * that behave like P-frames. */
1264         avctx->has_b_frames = !(s->low_delay);
1265
1266         assert((avctx->sub_id==1) == (avctx->codec_id==CODEC_ID_MPEG1VIDEO));
1267         if(avctx->codec_id==CODEC_ID_MPEG1VIDEO){
1268             //MPEG-1 fps
1269             avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1270             avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1271             //MPEG-1 aspect
1272             avctx->sample_aspect_ratio= av_d2q(
1273                     1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1274             avctx->ticks_per_frame=1;
1275         }else{//MPEG-2
1276         //MPEG-2 fps
1277             av_reduce(
1278                 &s->avctx->time_base.den,
1279                 &s->avctx->time_base.num,
1280                 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
1281                 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1282                 1<<30);
1283             avctx->ticks_per_frame=2;
1284         //MPEG-2 aspect
1285             if(s->aspect_ratio_info > 1){
1286                 //we ignore the spec here as reality does not match the spec, see for example
1287                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1288                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) || 1){
1289                     s->avctx->sample_aspect_ratio=
1290                         av_div_q(
1291                          ff_mpeg2_aspect[s->aspect_ratio_info],
1292                          (AVRational){s->width, s->height}
1293                          );
1294                 }else{
1295                     s->avctx->sample_aspect_ratio=
1296                         av_div_q(
1297                          ff_mpeg2_aspect[s->aspect_ratio_info],
1298                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
1299                         );
1300                 }
1301             }else{
1302                 s->avctx->sample_aspect_ratio=
1303                     ff_mpeg2_aspect[s->aspect_ratio_info];
1304             }
1305         }//MPEG-2
1306
1307         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1308         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1309         //until then pix_fmt may be changed right after codec init
1310         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
1311             avctx->hwaccel ||
1312             s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
1313             if( avctx->idct_algo == FF_IDCT_AUTO )
1314                 avctx->idct_algo = FF_IDCT_SIMPLE;
1315
1316         /* Quantization matrices may need reordering
1317          * if DCT permutation is changed. */
1318         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1319
1320         if (MPV_common_init(s) < 0)
1321             return -2;
1322
1323         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
1324         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
1325         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1326         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1327
1328         s1->mpeg_enc_ctx_allocated = 1;
1329     }
1330     return 0;
1331 }
1332
1333 static int mpeg1_decode_picture(AVCodecContext *avctx,
1334                                 const uint8_t *buf, int buf_size)
1335 {
1336     Mpeg1Context *s1 = avctx->priv_data;
1337     MpegEncContext *s = &s1->mpeg_enc_ctx;
1338     int ref, f_code, vbv_delay;
1339
1340     if(mpeg_decode_postinit(s->avctx) < 0)
1341        return -2;
1342
1343     init_get_bits(&s->gb, buf, buf_size*8);
1344
1345     ref = get_bits(&s->gb, 10); /* temporal ref */
1346     s->pict_type = get_bits(&s->gb, 3);
1347     if(s->pict_type == 0 || s->pict_type > 3)
1348         return -1;
1349
1350     vbv_delay= get_bits(&s->gb, 16);
1351     if (s->pict_type == FF_P_TYPE || s->pict_type == FF_B_TYPE) {
1352         s->full_pel[0] = get_bits1(&s->gb);
1353         f_code = get_bits(&s->gb, 3);
1354         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1355             return -1;
1356         s->mpeg_f_code[0][0] = f_code;
1357         s->mpeg_f_code[0][1] = f_code;
1358     }
1359     if (s->pict_type == FF_B_TYPE) {
1360         s->full_pel[1] = get_bits1(&s->gb);
1361         f_code = get_bits(&s->gb, 3);
1362         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1363             return -1;
1364         s->mpeg_f_code[1][0] = f_code;
1365         s->mpeg_f_code[1][1] = f_code;
1366     }
1367     s->current_picture.pict_type= s->pict_type;
1368     s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1369
1370     if(avctx->debug & FF_DEBUG_PICT_INFO)
1371         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1372
1373     s->y_dc_scale = 8;
1374     s->c_dc_scale = 8;
1375     s->first_slice = 1;
1376     return 0;
1377 }
1378
1379 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1380 {
1381     MpegEncContext *s= &s1->mpeg_enc_ctx;
1382     int horiz_size_ext, vert_size_ext;
1383     int bit_rate_ext;
1384
1385     skip_bits(&s->gb, 1); /* profile and level esc*/
1386     s->avctx->profile= get_bits(&s->gb, 3);
1387     s->avctx->level= get_bits(&s->gb, 4);
1388     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1389     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1390     horiz_size_ext = get_bits(&s->gb, 2);
1391     vert_size_ext = get_bits(&s->gb, 2);
1392     s->width |= (horiz_size_ext << 12);
1393     s->height |= (vert_size_ext << 12);
1394     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1395     s->bit_rate += (bit_rate_ext << 18) * 400;
1396     skip_bits1(&s->gb); /* marker */
1397     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1398
1399     s->low_delay = get_bits1(&s->gb);
1400     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1401
1402     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1403     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1404
1405     dprintf(s->avctx, "sequence extension\n");
1406     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1407     s->avctx->sub_id = 2; /* indicates MPEG-2 found */
1408
1409     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1410         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1411                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1412
1413 }
1414
1415 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1416 {
1417     MpegEncContext *s= &s1->mpeg_enc_ctx;
1418     int color_description, w, h;
1419
1420     skip_bits(&s->gb, 3); /* video format */
1421     color_description= get_bits1(&s->gb);
1422     if(color_description){
1423         skip_bits(&s->gb, 8); /* color primaries */
1424         skip_bits(&s->gb, 8); /* transfer_characteristics */
1425         skip_bits(&s->gb, 8); /* matrix_coefficients */
1426     }
1427     w= get_bits(&s->gb, 14);
1428     skip_bits(&s->gb, 1); //marker
1429     h= get_bits(&s->gb, 14);
1430     skip_bits(&s->gb, 1); //marker
1431
1432     s1->pan_scan.width= 16*w;
1433     s1->pan_scan.height=16*h;
1434
1435     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1436         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1437 }
1438
1439 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1440 {
1441     MpegEncContext *s= &s1->mpeg_enc_ctx;
1442     int i,nofco;
1443
1444     nofco = 1;
1445     if(s->progressive_sequence){
1446         if(s->repeat_first_field){
1447             nofco++;
1448             if(s->top_field_first)
1449                 nofco++;
1450         }
1451     }else{
1452         if(s->picture_structure == PICT_FRAME){
1453             nofco++;
1454             if(s->repeat_first_field)
1455                 nofco++;
1456         }
1457     }
1458     for(i=0; i<nofco; i++){
1459         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1460         skip_bits(&s->gb, 1); //marker
1461         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1462         skip_bits(&s->gb, 1); //marker
1463     }
1464
1465     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1466         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1467             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1468             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1469             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1470         );
1471 }
1472
1473 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1474 {
1475     int i, v, j;
1476
1477     dprintf(s->avctx, "matrix extension\n");
1478
1479     if (get_bits1(&s->gb)) {
1480         for(i=0;i<64;i++) {
1481             v = get_bits(&s->gb, 8);
1482             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1483             s->intra_matrix[j] = v;
1484             s->chroma_intra_matrix[j] = v;
1485         }
1486     }
1487     if (get_bits1(&s->gb)) {
1488         for(i=0;i<64;i++) {
1489             v = get_bits(&s->gb, 8);
1490             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1491             s->inter_matrix[j] = v;
1492             s->chroma_inter_matrix[j] = v;
1493         }
1494     }
1495     if (get_bits1(&s->gb)) {
1496         for(i=0;i<64;i++) {
1497             v = get_bits(&s->gb, 8);
1498             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1499             s->chroma_intra_matrix[j] = v;
1500         }
1501     }
1502     if (get_bits1(&s->gb)) {
1503         for(i=0;i<64;i++) {
1504             v = get_bits(&s->gb, 8);
1505             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1506             s->chroma_inter_matrix[j] = v;
1507         }
1508     }
1509 }
1510
1511 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1512 {
1513     MpegEncContext *s= &s1->mpeg_enc_ctx;
1514
1515     s->full_pel[0] = s->full_pel[1] = 0;
1516     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1517     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1518     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1519     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1520     if(!s->pict_type && s1->mpeg_enc_ctx_allocated){
1521         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1522         if(s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1]==15){
1523             if(s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1524                 s->pict_type= FF_I_TYPE;
1525             else
1526                 s->pict_type= FF_P_TYPE;
1527         }else
1528             s->pict_type= FF_B_TYPE;
1529         s->current_picture.pict_type= s->pict_type;
1530         s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1531         s->first_slice= 1;
1532     }
1533     s->intra_dc_precision = get_bits(&s->gb, 2);
1534     s->picture_structure = get_bits(&s->gb, 2);
1535     s->top_field_first = get_bits1(&s->gb);
1536     s->frame_pred_frame_dct = get_bits1(&s->gb);
1537     s->concealment_motion_vectors = get_bits1(&s->gb);
1538     s->q_scale_type = get_bits1(&s->gb);
1539     s->intra_vlc_format = get_bits1(&s->gb);
1540     s->alternate_scan = get_bits1(&s->gb);
1541     s->repeat_first_field = get_bits1(&s->gb);
1542     s->chroma_420_type = get_bits1(&s->gb);
1543     s->progressive_frame = get_bits1(&s->gb);
1544
1545     if(s->picture_structure == PICT_FRAME){
1546         s->first_field=0;
1547         s->v_edge_pos= 16*s->mb_height;
1548     }else{
1549         s->first_field ^= 1;
1550         s->v_edge_pos=  8*s->mb_height;
1551         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1552     }
1553
1554     if(s->alternate_scan){
1555         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1556         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1557     }else{
1558         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1559         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1560     }
1561
1562     /* composite display not parsed */
1563     dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1564     dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1565     dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1566     dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1567     dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1568     dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1569     dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1570     dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1571     dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1572 }
1573
1574 static void mpeg_decode_extension(AVCodecContext *avctx,
1575                                   const uint8_t *buf, int buf_size)
1576 {
1577     Mpeg1Context *s1 = avctx->priv_data;
1578     MpegEncContext *s = &s1->mpeg_enc_ctx;
1579     int ext_type;
1580
1581     init_get_bits(&s->gb, buf, buf_size*8);
1582
1583     ext_type = get_bits(&s->gb, 4);
1584     switch(ext_type) {
1585     case 0x1:
1586         mpeg_decode_sequence_extension(s1);
1587         break;
1588     case 0x2:
1589         mpeg_decode_sequence_display_extension(s1);
1590         break;
1591     case 0x3:
1592         mpeg_decode_quant_matrix_extension(s);
1593         break;
1594     case 0x7:
1595         mpeg_decode_picture_display_extension(s1);
1596         break;
1597     case 0x8:
1598         mpeg_decode_picture_coding_extension(s1);
1599         break;
1600     }
1601 }
1602
1603 static void exchange_uv(MpegEncContext *s){
1604     DCTELEM (*tmp)[64];
1605
1606     tmp           = s->pblocks[4];
1607     s->pblocks[4] = s->pblocks[5];
1608     s->pblocks[5] = tmp;
1609 }
1610
1611 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size){
1612     AVCodecContext *avctx= s->avctx;
1613     Mpeg1Context *s1 = (Mpeg1Context*)s;
1614
1615     /* start frame decoding */
1616     if(s->first_field || s->picture_structure==PICT_FRAME){
1617         if(MPV_frame_start(s, avctx) < 0)
1618             return -1;
1619
1620         ff_er_frame_start(s);
1621
1622         /* first check if we must repeat the frame */
1623         s->current_picture_ptr->repeat_pict = 0;
1624         if (s->repeat_first_field) {
1625             if (s->progressive_sequence) {
1626                 if (s->top_field_first)
1627                     s->current_picture_ptr->repeat_pict = 4;
1628                 else
1629                     s->current_picture_ptr->repeat_pict = 2;
1630             } else if (s->progressive_frame) {
1631                 s->current_picture_ptr->repeat_pict = 1;
1632             }
1633         }
1634
1635         *s->current_picture_ptr->pan_scan= s1->pan_scan;
1636     }else{ //second field
1637             int i;
1638
1639             if(!s->current_picture_ptr){
1640                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1641                 return -1;
1642             }
1643
1644             for(i=0; i<4; i++){
1645                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1646                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1647                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1648                 }
1649             }
1650     }
1651
1652     if (avctx->hwaccel) {
1653         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1654             return -1;
1655     }
1656
1657 // MPV_frame_start will call this function too,
1658 // but we need to call it on every field
1659     if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1660         if(ff_xvmc_field_start(s,avctx) < 0)
1661             return -1;
1662
1663     return 0;
1664 }
1665
1666 #define DECODE_SLICE_ERROR -1
1667 #define DECODE_SLICE_OK 0
1668
1669 /**
1670  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1671  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1672  *         DECODE_SLICE_OK if this slice is ok<br>
1673  */
1674 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1675                              const uint8_t **buf, int buf_size)
1676 {
1677     MpegEncContext *s = &s1->mpeg_enc_ctx;
1678     AVCodecContext *avctx= s->avctx;
1679     const int field_pic= s->picture_structure != PICT_FRAME;
1680     const int lowres= s->avctx->lowres;
1681
1682     s->resync_mb_x=
1683     s->resync_mb_y= -1;
1684
1685     if (mb_y<<field_pic >= s->mb_height){
1686         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
1687         return -1;
1688     }
1689
1690     init_get_bits(&s->gb, *buf, buf_size*8);
1691
1692     ff_mpeg1_clean_buffers(s);
1693     s->interlaced_dct = 0;
1694
1695     s->qscale = get_qscale(s);
1696
1697     if(s->qscale == 0){
1698         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1699         return -1;
1700     }
1701
1702     /* extra slice info */
1703     while (get_bits1(&s->gb) != 0) {
1704         skip_bits(&s->gb, 8);
1705     }
1706
1707     s->mb_x=0;
1708
1709     if (avctx->hwaccel) {
1710         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1711         int start_code = -1;
1712         buf_end = ff_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1713         if (buf_end < *buf + buf_size)
1714             buf_end -= 4;
1715         s->mb_y = mb_y;
1716         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1717             return DECODE_SLICE_ERROR;
1718         *buf = buf_end;
1719         return DECODE_SLICE_OK;
1720     }
1721
1722     for(;;) {
1723         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1724         if (code < 0){
1725             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1726             return -1;
1727         }
1728         if (code >= 33) {
1729             if (code == 33) {
1730                 s->mb_x += 33;
1731             }
1732             /* otherwise, stuffing, nothing to do */
1733         } else {
1734             s->mb_x += code;
1735             break;
1736         }
1737     }
1738     if(s->mb_x >= (unsigned)s->mb_width){
1739         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1740         return -1;
1741     }
1742
1743     s->resync_mb_x= s->mb_x;
1744     s->resync_mb_y= s->mb_y= mb_y;
1745     s->mb_skip_run= 0;
1746     ff_init_block_index(s);
1747
1748     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1749         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1750              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",
1751                  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],
1752                  s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
1753                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1754                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1755                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1756         }
1757     }
1758
1759     for(;;) {
1760         //If 1, we memcpy blocks in xvmcvideo.
1761         if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1762             ff_xvmc_init_block(s);//set s->block
1763
1764         if(mpeg_decode_mb(s, s->block) < 0)
1765             return -1;
1766
1767         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1768             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
1769             int xy = s->mb_x*2 + s->mb_y*2*wrap;
1770             int motion_x, motion_y, dir, i;
1771             if(field_pic && !s->first_field)
1772                 xy += wrap/2;
1773
1774             for(i=0; i<2; i++){
1775                 for(dir=0; dir<2; dir++){
1776                     if (s->mb_intra || (dir==1 && s->pict_type != FF_B_TYPE)) {
1777                         motion_x = motion_y = 0;
1778                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1779                         motion_x = s->mv[dir][0][0];
1780                         motion_y = s->mv[dir][0][1];
1781                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1782                         motion_x = s->mv[dir][i][0];
1783                         motion_y = s->mv[dir][i][1];
1784                     }
1785
1786                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1787                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1788                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1789                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1790                     s->current_picture.ref_index [dir][xy    ]=
1791                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
1792                     assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1793                 }
1794                 xy += wrap;
1795             }
1796         }
1797
1798         s->dest[0] += 16 >> lowres;
1799         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1800         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1801
1802         MPV_decode_mb(s, s->block);
1803
1804         if (++s->mb_x >= s->mb_width) {
1805             const int mb_size= 16>>s->avctx->lowres;
1806
1807             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
1808
1809             s->mb_x = 0;
1810             s->mb_y++;
1811
1812             if(s->mb_y<<field_pic >= s->mb_height){
1813                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1814                 int is_d10= s->chroma_format==2 && s->pict_type==FF_I_TYPE && avctx->profile==0 && avctx->level==5
1815                             && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1816                             && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1817
1818                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1819                    || (avctx->error_recognition >= FF_ER_AGGRESSIVE && left>8)){
1820                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1821                     return -1;
1822                 }else
1823                     goto eos;
1824             }
1825
1826             ff_init_block_index(s);
1827         }
1828
1829         /* skip mb handling */
1830         if (s->mb_skip_run == -1) {
1831             /* read increment again */
1832             s->mb_skip_run = 0;
1833             for(;;) {
1834                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1835                 if (code < 0){
1836                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1837                     return -1;
1838                 }
1839                 if (code >= 33) {
1840                     if (code == 33) {
1841                         s->mb_skip_run += 33;
1842                     }else if(code == 35){
1843                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1844                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1845                             return -1;
1846                         }
1847                         goto eos; /* end of slice */
1848                     }
1849                     /* otherwise, stuffing, nothing to do */
1850                 } else {
1851                     s->mb_skip_run += code;
1852                     break;
1853                 }
1854             }
1855             if(s->mb_skip_run){
1856                 int i;
1857                 if(s->pict_type == FF_I_TYPE){
1858                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1859                     return -1;
1860                 }
1861
1862                 /* skip mb */
1863                 s->mb_intra = 0;
1864                 for(i=0;i<12;i++)
1865                     s->block_last_index[i] = -1;
1866                 if(s->picture_structure == PICT_FRAME)
1867                     s->mv_type = MV_TYPE_16X16;
1868                 else
1869                     s->mv_type = MV_TYPE_FIELD;
1870                 if (s->pict_type == FF_P_TYPE) {
1871                     /* if P type, zero motion vector is implied */
1872                     s->mv_dir = MV_DIR_FORWARD;
1873                     s->mv[0][0][0] = s->mv[0][0][1] = 0;
1874                     s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1875                     s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1876                     s->field_select[0][0]= s->picture_structure - 1;
1877                 } else {
1878                     /* if B type, reuse previous vectors and directions */
1879                     s->mv[0][0][0] = s->last_mv[0][0][0];
1880                     s->mv[0][0][1] = s->last_mv[0][0][1];
1881                     s->mv[1][0][0] = s->last_mv[1][0][0];
1882                     s->mv[1][0][1] = s->last_mv[1][0][1];
1883                 }
1884             }
1885         }
1886     }
1887 eos: // end of slice
1888     *buf += (get_bits_count(&s->gb)-1)/8;
1889 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1890     return 0;
1891 }
1892
1893 static int slice_decode_thread(AVCodecContext *c, void *arg){
1894     MpegEncContext *s= *(void**)arg;
1895     const uint8_t *buf= s->gb.buffer;
1896     int mb_y= s->start_mb_y;
1897
1898     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
1899
1900     for(;;){
1901         uint32_t start_code;
1902         int ret;
1903
1904         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1905         emms_c();
1906 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1907 //ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, s->start_mb_y, s->end_mb_y, s->error_count);
1908         if(ret < 0){
1909             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1910                 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, AC_ERROR|DC_ERROR|MV_ERROR);
1911         }else{
1912             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);
1913         }
1914
1915         if(s->mb_y == s->end_mb_y)
1916             return 0;
1917
1918         start_code= -1;
1919         buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1920         mb_y= start_code - SLICE_MIN_START_CODE;
1921         if(mb_y < 0 || mb_y >= s->end_mb_y)
1922             return -1;
1923     }
1924
1925     return 0; //not reached
1926 }
1927
1928 /**
1929  * Handles slice ends.
1930  * @return 1 if it seems to be the last slice
1931  */
1932 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1933 {
1934     Mpeg1Context *s1 = avctx->priv_data;
1935     MpegEncContext *s = &s1->mpeg_enc_ctx;
1936
1937     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1938         return 0;
1939
1940     if (s->avctx->hwaccel) {
1941         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1942             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
1943     }
1944
1945     if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1946         ff_xvmc_field_end(s);
1947
1948     /* end of slice reached */
1949     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1950         /* end of image */
1951
1952         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1953
1954         ff_er_frame_end(s);
1955
1956         MPV_frame_end(s);
1957
1958         if (s->pict_type == FF_B_TYPE || s->low_delay) {
1959             *pict= *(AVFrame*)s->current_picture_ptr;
1960             ff_print_debug_info(s, pict);
1961         } else {
1962             s->picture_number++;
1963             /* latency of 1 frame for I- and P-frames */
1964             /* XXX: use another variable than picture_number */
1965             if (s->last_picture_ptr != NULL) {
1966                 *pict= *(AVFrame*)s->last_picture_ptr;
1967                  ff_print_debug_info(s, pict);
1968             }
1969         }
1970
1971         return 1;
1972     } else {
1973         return 0;
1974     }
1975 }
1976
1977 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1978                                  const uint8_t *buf, int buf_size)
1979 {
1980     Mpeg1Context *s1 = avctx->priv_data;
1981     MpegEncContext *s = &s1->mpeg_enc_ctx;
1982     int width,height;
1983     int i, v, j;
1984
1985     init_get_bits(&s->gb, buf, buf_size*8);
1986
1987     width = get_bits(&s->gb, 12);
1988     height = get_bits(&s->gb, 12);
1989     if (width <= 0 || height <= 0)
1990         return -1;
1991     s->aspect_ratio_info= get_bits(&s->gb, 4);
1992     if (s->aspect_ratio_info == 0) {
1993         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1994         if (avctx->error_recognition >= FF_ER_COMPLIANT)
1995             return -1;
1996     }
1997     s->frame_rate_index = get_bits(&s->gb, 4);
1998     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1999         return -1;
2000     s->bit_rate = get_bits(&s->gb, 18) * 400;
2001     if (get_bits1(&s->gb) == 0) /* marker */
2002         return -1;
2003     s->width = width;
2004     s->height = height;
2005
2006     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
2007     skip_bits(&s->gb, 1);
2008
2009     /* get matrix */
2010     if (get_bits1(&s->gb)) {
2011         for(i=0;i<64;i++) {
2012             v = get_bits(&s->gb, 8);
2013             if(v==0){
2014                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
2015                 return -1;
2016             }
2017             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2018             s->intra_matrix[j] = v;
2019             s->chroma_intra_matrix[j] = v;
2020         }
2021 #ifdef DEBUG
2022         dprintf(s->avctx, "intra matrix present\n");
2023         for(i=0;i<64;i++)
2024             dprintf(s->avctx, " %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
2025         dprintf(s->avctx, "\n");
2026 #endif
2027     } else {
2028         for(i=0;i<64;i++) {
2029             j = s->dsp.idct_permutation[i];
2030             v = ff_mpeg1_default_intra_matrix[i];
2031             s->intra_matrix[j] = v;
2032             s->chroma_intra_matrix[j] = v;
2033         }
2034     }
2035     if (get_bits1(&s->gb)) {
2036         for(i=0;i<64;i++) {
2037             v = get_bits(&s->gb, 8);
2038             if(v==0){
2039                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2040                 return -1;
2041             }
2042             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2043             s->inter_matrix[j] = v;
2044             s->chroma_inter_matrix[j] = v;
2045         }
2046 #ifdef DEBUG
2047         dprintf(s->avctx, "non-intra matrix present\n");
2048         for(i=0;i<64;i++)
2049             dprintf(s->avctx, " %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
2050         dprintf(s->avctx, "\n");
2051 #endif
2052     } else {
2053         for(i=0;i<64;i++) {
2054             int j= s->dsp.idct_permutation[i];
2055             v = ff_mpeg1_default_non_intra_matrix[i];
2056             s->inter_matrix[j] = v;
2057             s->chroma_inter_matrix[j] = v;
2058         }
2059     }
2060
2061     if(show_bits(&s->gb, 23) != 0){
2062         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2063         return -1;
2064     }
2065
2066     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
2067     s->progressive_sequence = 1;
2068     s->progressive_frame = 1;
2069     s->picture_structure = PICT_FRAME;
2070     s->frame_pred_frame_dct = 1;
2071     s->chroma_format = 1;
2072     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2073     avctx->sub_id = 1; /* indicates MPEG-1 */
2074     s->out_format = FMT_MPEG1;
2075     s->swap_uv = 0;//AFAIK VCR2 does not have SEQ_HEADER
2076     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2077
2078     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2079         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2080                s->avctx->rc_buffer_size, s->bit_rate);
2081
2082     return 0;
2083 }
2084
2085 static int vcr2_init_sequence(AVCodecContext *avctx)
2086 {
2087     Mpeg1Context *s1 = avctx->priv_data;
2088     MpegEncContext *s = &s1->mpeg_enc_ctx;
2089     int i, v;
2090
2091     /* start new MPEG-1 context decoding */
2092     s->out_format = FMT_MPEG1;
2093     if (s1->mpeg_enc_ctx_allocated) {
2094         MPV_common_end(s);
2095     }
2096     s->width  = avctx->coded_width;
2097     s->height = avctx->coded_height;
2098     avctx->has_b_frames= 0; //true?
2099     s->low_delay= 1;
2100
2101     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2102     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
2103
2104     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
2105         s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
2106         if( avctx->idct_algo == FF_IDCT_AUTO )
2107             avctx->idct_algo = FF_IDCT_SIMPLE;
2108
2109     if (MPV_common_init(s) < 0)
2110         return -1;
2111     exchange_uv(s);//common init reset pblocks, so we swap them here
2112     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2113     s1->mpeg_enc_ctx_allocated = 1;
2114
2115     for(i=0;i<64;i++) {
2116         int j= s->dsp.idct_permutation[i];
2117         v = ff_mpeg1_default_intra_matrix[i];
2118         s->intra_matrix[j] = v;
2119         s->chroma_intra_matrix[j] = v;
2120
2121         v = ff_mpeg1_default_non_intra_matrix[i];
2122         s->inter_matrix[j] = v;
2123         s->chroma_inter_matrix[j] = v;
2124     }
2125
2126     s->progressive_sequence = 1;
2127     s->progressive_frame = 1;
2128     s->picture_structure = PICT_FRAME;
2129     s->frame_pred_frame_dct = 1;
2130     s->chroma_format = 1;
2131     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2132     avctx->sub_id = 2; /* indicates MPEG-2 */
2133     return 0;
2134 }
2135
2136
2137 static void mpeg_decode_user_data(AVCodecContext *avctx,
2138                                   const uint8_t *buf, int buf_size)
2139 {
2140     const uint8_t *p;
2141     int len, flags;
2142     p = buf;
2143     len = buf_size;
2144
2145     /* we parse the DTG active format information */
2146     if (len >= 5 &&
2147         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2148         flags = p[4];
2149         p += 5;
2150         len -= 5;
2151         if (flags & 0x80) {
2152             /* skip event id */
2153             if (len < 2)
2154                 return;
2155             p += 2;
2156             len -= 2;
2157         }
2158         if (flags & 0x40) {
2159             if (len < 1)
2160                 return;
2161             avctx->dtg_active_format = p[0] & 0x0f;
2162         }
2163     }
2164 }
2165
2166 static void mpeg_decode_gop(AVCodecContext *avctx,
2167                             const uint8_t *buf, int buf_size){
2168     Mpeg1Context *s1 = avctx->priv_data;
2169     MpegEncContext *s = &s1->mpeg_enc_ctx;
2170
2171     int drop_frame_flag;
2172     int time_code_hours, time_code_minutes;
2173     int time_code_seconds, time_code_pictures;
2174     int closed_gop, broken_link;
2175
2176     init_get_bits(&s->gb, buf, buf_size*8);
2177
2178     drop_frame_flag = get_bits1(&s->gb);
2179
2180     time_code_hours=get_bits(&s->gb,5);
2181     time_code_minutes = get_bits(&s->gb,6);
2182     skip_bits1(&s->gb);//marker bit
2183     time_code_seconds = get_bits(&s->gb,6);
2184     time_code_pictures = get_bits(&s->gb,6);
2185
2186     closed_gop  = get_bits1(&s->gb);
2187     /*broken_link indicate that after editing the
2188       reference frames of the first B-Frames after GOP I-Frame
2189       are missing (open gop)*/
2190     broken_link = get_bits1(&s->gb);
2191
2192     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2193         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2194             time_code_hours, time_code_minutes, time_code_seconds,
2195             time_code_pictures, closed_gop, broken_link);
2196 }
2197 /**
2198  * Finds the end of the current frame in the bitstream.
2199  * @return the position of the first byte of the next frame, or -1
2200  */
2201 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
2202 {
2203     int i;
2204     uint32_t state= pc->state;
2205
2206     /* EOF considered as end of frame */
2207     if (buf_size == 0)
2208         return 0;
2209
2210 /*
2211  0  frame start         -> 1/4
2212  1  first_SEQEXT        -> 0/2
2213  2  first field start   -> 3/0
2214  3  second_SEQEXT       -> 2/0
2215  4  searching end
2216 */
2217
2218     for(i=0; i<buf_size; i++){
2219         assert(pc->frame_start_found>=0 && pc->frame_start_found<=4);
2220         if(pc->frame_start_found&1){
2221             if(state == EXT_START_CODE && (buf[i]&0xF0) != 0x80)
2222                 pc->frame_start_found--;
2223             else if(state == EXT_START_CODE+2){
2224                 if((buf[i]&3) == 3) pc->frame_start_found= 0;
2225                 else                pc->frame_start_found= (pc->frame_start_found+1)&3;
2226             }
2227             state++;
2228         }else{
2229             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2230             if(pc->frame_start_found==0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2231                 i++;
2232                 pc->frame_start_found=4;
2233             }
2234             if(state == SEQ_END_CODE){
2235                 pc->state=-1;
2236                 return i+1;
2237             }
2238             if(pc->frame_start_found==2 && state == SEQ_START_CODE)
2239                 pc->frame_start_found= 0;
2240             if(pc->frame_start_found<4 && state == EXT_START_CODE)
2241                 pc->frame_start_found++;
2242             if(pc->frame_start_found == 4 && (state&0xFFFFFF00) == 0x100){
2243                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2244                     pc->frame_start_found=0;
2245                     pc->state=-1;
2246                     return i-3;
2247                 }
2248             }
2249             if(s && state == PICTURE_START_CODE){
2250                 ff_fetch_timestamp(s, i-4, 1);
2251             }
2252         }
2253     }
2254     pc->state= state;
2255     return END_NOT_FOUND;
2256 }
2257
2258 static int decode_chunks(AVCodecContext *avctx,
2259                              AVFrame *picture, int *data_size,
2260                              const uint8_t *buf, int buf_size);
2261
2262 /* handle buffering and image synchronisation */
2263 static int mpeg_decode_frame(AVCodecContext *avctx,
2264                              void *data, int *data_size,
2265                              AVPacket *avpkt)
2266 {
2267     const uint8_t *buf = avpkt->data;
2268     int buf_size = avpkt->size;
2269     Mpeg1Context *s = avctx->priv_data;
2270     AVFrame *picture = data;
2271     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2272     dprintf(avctx, "fill_buffer\n");
2273
2274     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2275         /* special case for last picture */
2276         if (s2->low_delay==0 && s2->next_picture_ptr) {
2277             *picture= *(AVFrame*)s2->next_picture_ptr;
2278             s2->next_picture_ptr= NULL;
2279
2280             *data_size = sizeof(AVFrame);
2281         }
2282         return buf_size;
2283     }
2284
2285     if(s2->flags&CODEC_FLAG_TRUNCATED){
2286         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
2287
2288         if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2289             return buf_size;
2290     }
2291
2292 #if 0
2293     if (s->repeat_field % 2 == 1) {
2294         s->repeat_field++;
2295         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2296         //        s2->picture_number, s->repeat_field);
2297         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2298             *data_size = sizeof(AVPicture);
2299             goto the_end;
2300         }
2301     }
2302 #endif
2303
2304     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == AV_RL32("VCR2"))
2305         vcr2_init_sequence(avctx);
2306
2307     s->slice_count= 0;
2308
2309     if(avctx->extradata && !avctx->frame_number)
2310         decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
2311
2312     return decode_chunks(avctx, picture, data_size, buf, buf_size);
2313 }
2314
2315 static int decode_chunks(AVCodecContext *avctx,
2316                              AVFrame *picture, int *data_size,
2317                              const uint8_t *buf, int buf_size)
2318 {
2319     Mpeg1Context *s = avctx->priv_data;
2320     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2321     const uint8_t *buf_ptr = buf;
2322     const uint8_t *buf_end = buf + buf_size;
2323     int ret, input_size;
2324
2325     for(;;) {
2326         /* find next start code */
2327         uint32_t start_code = -1;
2328         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2329         if (start_code > 0x1ff){
2330             if(s2->pict_type != FF_B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2331                 if(avctx->thread_count > 1){
2332                     int i;
2333
2334                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count, sizeof(void*));
2335                     for(i=0; i<s->slice_count; i++)
2336                         s2->error_count += s2->thread_context[i]->error_count;
2337                 }
2338
2339                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
2340                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2341
2342                 if (slice_end(avctx, picture)) {
2343                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2344                         *data_size = sizeof(AVPicture);
2345                 }
2346             }
2347             s2->pict_type= 0;
2348             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2349         }
2350
2351         input_size = buf_end - buf_ptr;
2352
2353         if(avctx->debug & FF_DEBUG_STARTCODE){
2354             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2355         }
2356
2357         /* prepare data for next start code */
2358         switch(start_code) {
2359         case SEQ_START_CODE:
2360             mpeg1_decode_sequence(avctx, buf_ptr,
2361                                     input_size);
2362             break;
2363
2364         case PICTURE_START_CODE:
2365             /* we have a complete image: we try to decompress it */
2366             if(mpeg1_decode_picture(avctx,
2367                                     buf_ptr, input_size) < 0)
2368                 s2->pict_type=0;
2369             break;
2370         case EXT_START_CODE:
2371             mpeg_decode_extension(avctx,
2372                                     buf_ptr, input_size);
2373             break;
2374         case USER_START_CODE:
2375             mpeg_decode_user_data(avctx,
2376                                     buf_ptr, input_size);
2377             break;
2378         case GOP_START_CODE:
2379             s2->first_field=0;
2380             mpeg_decode_gop(avctx,
2381                                     buf_ptr, input_size);
2382             break;
2383         default:
2384             if (start_code >= SLICE_MIN_START_CODE &&
2385                 start_code <= SLICE_MAX_START_CODE) {
2386                 int mb_y= start_code - SLICE_MIN_START_CODE;
2387
2388                 if(s2->last_picture_ptr==NULL){
2389                 /* Skip B-frames if we do not have reference frames. */
2390                     if(s2->pict_type==FF_B_TYPE) break;
2391                 }
2392                 if(s2->next_picture_ptr==NULL){
2393                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2394                     if(s2->pict_type==FF_P_TYPE && (s2->first_field || s2->picture_structure==PICT_FRAME)) break;
2395                 }
2396                 /* Skip B-frames if we are in a hurry. */
2397                 if(avctx->hurry_up && s2->pict_type==FF_B_TYPE) break;
2398                 if(  (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==FF_B_TYPE)
2399                     ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=FF_I_TYPE)
2400                     || avctx->skip_frame >= AVDISCARD_ALL)
2401                     break;
2402                 /* Skip everything if we are in a hurry>=5. */
2403                 if(avctx->hurry_up>=5) break;
2404
2405                 if (!s->mpeg_enc_ctx_allocated) break;
2406
2407                 if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
2408                     if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2409                         break;
2410                 }
2411
2412                 if(!s2->pict_type){
2413                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2414                     break;
2415                 }
2416
2417                 if(s2->first_slice){
2418                     s2->first_slice=0;
2419                     if(mpeg_field_start(s2, buf, buf_size) < 0)
2420                         return -1;
2421                 }
2422                 if(!s2->current_picture_ptr){
2423                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2424                     return -1;
2425                 }
2426
2427                 if (avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU) {
2428                     s->slice_count++;
2429                     break;
2430                 }
2431
2432                 if(avctx->thread_count > 1){
2433                     int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2434                     if(threshold <= mb_y){
2435                         MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2436
2437                         thread_context->start_mb_y= mb_y;
2438                         thread_context->end_mb_y  = s2->mb_height;
2439                         if(s->slice_count){
2440                             s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2441                             ff_update_duplicate_context(thread_context, s2);
2442                         }
2443                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2444                         s->slice_count++;
2445                     }
2446                     buf_ptr += 2; //FIXME add minimum number of bytes per slice
2447                 }else{
2448                     ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2449                     emms_c();
2450
2451                     if(ret < 0){
2452                         if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2453                             ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, AC_ERROR|DC_ERROR|MV_ERROR);
2454                     }else{
2455                         ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, AC_END|DC_END|MV_END);
2456                     }
2457                 }
2458             }
2459             break;
2460         }
2461     }
2462 }
2463
2464 static int mpeg_decode_end(AVCodecContext *avctx)
2465 {
2466     Mpeg1Context *s = avctx->priv_data;
2467
2468     if (s->mpeg_enc_ctx_allocated)
2469         MPV_common_end(&s->mpeg_enc_ctx);
2470     return 0;
2471 }
2472
2473 AVCodec mpeg1video_decoder = {
2474     "mpeg1video",
2475     CODEC_TYPE_VIDEO,
2476     CODEC_ID_MPEG1VIDEO,
2477     sizeof(Mpeg1Context),
2478     mpeg_decode_init,
2479     NULL,
2480     mpeg_decode_end,
2481     mpeg_decode_frame,
2482     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2483     .flush= ff_mpeg_flush,
2484     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2485 };
2486
2487 AVCodec mpeg2video_decoder = {
2488     "mpeg2video",
2489     CODEC_TYPE_VIDEO,
2490     CODEC_ID_MPEG2VIDEO,
2491     sizeof(Mpeg1Context),
2492     mpeg_decode_init,
2493     NULL,
2494     mpeg_decode_end,
2495     mpeg_decode_frame,
2496     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2497     .flush= ff_mpeg_flush,
2498     .long_name= NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2499 };
2500
2501 //legacy decoder
2502 AVCodec mpegvideo_decoder = {
2503     "mpegvideo",
2504     CODEC_TYPE_VIDEO,
2505     CODEC_ID_MPEG2VIDEO,
2506     sizeof(Mpeg1Context),
2507     mpeg_decode_init,
2508     NULL,
2509     mpeg_decode_end,
2510     mpeg_decode_frame,
2511     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2512     .flush= ff_mpeg_flush,
2513     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2514 };
2515
2516 #if CONFIG_MPEG_XVMC_DECODER
2517 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx){
2518     if( avctx->thread_count > 1)
2519         return -1;
2520     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2521         return -1;
2522     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2523         dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2524     }
2525     mpeg_decode_init(avctx);
2526
2527     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2528     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2529
2530     return 0;
2531 }
2532
2533 AVCodec mpeg_xvmc_decoder = {
2534     "mpegvideo_xvmc",
2535     CODEC_TYPE_VIDEO,
2536     CODEC_ID_MPEG2VIDEO_XVMC,
2537     sizeof(Mpeg1Context),
2538     mpeg_mc_decode_init,
2539     NULL,
2540     mpeg_decode_end,
2541     mpeg_decode_frame,
2542     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2543     .flush= ff_mpeg_flush,
2544     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2545 };
2546
2547 #endif
2548
2549 #if CONFIG_MPEG_VDPAU_DECODER
2550 AVCodec mpeg_vdpau_decoder = {
2551     "mpegvideo_vdpau",
2552     CODEC_TYPE_VIDEO,
2553     CODEC_ID_MPEG2VIDEO,
2554     sizeof(Mpeg1Context),
2555     mpeg_decode_init,
2556     NULL,
2557     mpeg_decode_end,
2558     mpeg_decode_frame,
2559     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2560     .flush= ff_mpeg_flush,
2561     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2562 };
2563 #endif
2564
2565 #if CONFIG_MPEG1_VDPAU_DECODER
2566 AVCodec mpeg1_vdpau_decoder = {
2567     "mpeg1video_vdpau",
2568     CODEC_TYPE_VIDEO,
2569     CODEC_ID_MPEG1VIDEO,
2570     sizeof(Mpeg1Context),
2571     mpeg_decode_init,
2572     NULL,
2573     mpeg_decode_end,
2574     mpeg_decode_frame,
2575     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2576     .flush= ff_mpeg_flush,
2577     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2578 };
2579 #endif
2580