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 "avcodec.h"
  30 #include "dsputil.h"
  31 #include "mpegvideo.h"
  32
  33 #include "mpeg12.h"
  34 #include "mpeg12data.h"
  35 #include "mpeg12decdata.h"
  36 #include "bytestream.h"
  37 #include "vdpau_internal.h"
  38 #include "xvmc_internal.h"
  39
  40 //#undef NDEBUG
  41 //#include <assert.h>
  42
  43
  44 #define MV_VLC_BITS 9
  45 #define MBINCR_VLC_BITS 9
  46 #define MB_PAT_VLC_BITS 9
  47 #define MB_PTYPE_VLC_BITS 6
  48 #define MB_BTYPE_VLC_BITS 6
  49
  50 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
  51                               DCTELEM *block,
  52                               int n);
  53 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
  54 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
  55                                         DCTELEM *block,
  56                                         int n);
  57 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
  58                                     DCTELEM *block,
  59                                     int n);
  60 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
  61 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
  62 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
  63 static void exchange_uv(MpegEncContext *s);
  64
  65 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
  66                                            PIX_FMT_XVMC_MPEG2_IDCT,
  67                                            PIX_FMT_XVMC_MPEG2_MC,
  68                                            PIX_FMT_NONE};
  69
  70 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
  71
  72
  73 #define INIT_2D_VLC_RL(rl, static_size)\
  74 {\
  75     static RL_VLC_ELEM rl_vlc_table[static_size];\
  76     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
  77              &rl.table_vlc[0][1], 4, 2,\
  78              &rl.table_vlc[0][0], 4, 2, static_size);\
  79 \
  80     rl.rl_vlc[0]= rl_vlc_table;\
  81     init_2d_vlc_rl(&rl);\
  82 }
  83
  84 static void init_2d_vlc_rl(RLTable *rl)
  85 {
  86     int i;
  87
  88     for(i=0; i<rl->vlc.table_size; i++){
  89         int code= rl->vlc.table[i][0];
  90         int len = rl->vlc.table[i][1];
  91         int level, run;
  92
  93         if(len==0){ // illegal code
  94             run= 65;
  95             level= MAX_LEVEL;
  96         }else if(len<0){ //more bits needed
  97             run= 0;
  98             level= code;
  99         }else{
 100             if(code==rl->n){ //esc
 101                 run= 65;
 102                 level= 0;
 103             }else if(code==rl->n+1){ //eob
 104                 run= 0;
 105                 level= 127;
 106             }else{
 107                 run=   rl->table_run  [code] + 1;
 108                 level= rl->table_level[code];
 109             }
 110         }
 111         rl->rl_vlc[0][i].len= len;
 112         rl->rl_vlc[0][i].level= level;
 113         rl->rl_vlc[0][i].run= run;
 114     }
 115 }
 116
 117 void ff_mpeg12_common_init(MpegEncContext *s)
 118 {
 119
 120     s->y_dc_scale_table=
 121     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
 122
 123 }
 124
 125 void ff_mpeg1_clean_buffers(MpegEncContext *s){
 126     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
 127     s->last_dc[1] = s->last_dc[0];
 128     s->last_dc[2] = s->last_dc[0];
 129     memset(s->last_mv, 0, sizeof(s->last_mv));
 130 }
 131
 132
 133 /******************************************/
 134 /* decoding */
 135
 136 static VLC mv_vlc;
 137 static VLC mbincr_vlc;
 138 static VLC mb_ptype_vlc;
 139 static VLC mb_btype_vlc;
 140 static VLC mb_pat_vlc;
 141
 142 av_cold void ff_mpeg12_init_vlcs(void)
 143 {
 144     static int done = 0;
 145
 146     if (!done) {
 147         done = 1;
 148
 149         INIT_VLC_STATIC(&dc_lum_vlc, DC_VLC_BITS, 12,
 150                  ff_mpeg12_vlc_dc_lum_bits, 1, 1,
 151                  ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
 152         INIT_VLC_STATIC(&dc_chroma_vlc,  DC_VLC_BITS, 12,
 153                  ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
 154                  ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
 155         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
 156                  &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
 157                  &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
 158         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
 159                  &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
 160                  &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
 161         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
 162                  &ff_mpeg12_mbPatTable[0][1], 2, 1,
 163                  &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
 164
 165         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
 166                  &table_mb_ptype[0][1], 2, 1,
 167                  &table_mb_ptype[0][0], 2, 1, 64);
 168         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
 169                  &table_mb_btype[0][1], 2, 1,
 170                  &table_mb_btype[0][0], 2, 1, 64);
 171         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
 172         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
 173
 174         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
 175         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
 176     }
 177 }
 178
 179 static inline int get_dmv(MpegEncContext *s)
 180 {
 181     if(get_bits1(&s->gb))
 182         return 1 - (get_bits1(&s->gb) << 1);
 183     else
 184         return 0;
 185 }
 186
 187 static inline int get_qscale(MpegEncContext *s)
 188 {
 189     int qscale = get_bits(&s->gb, 5);
 190     if (s->q_scale_type) {
 191         return non_linear_qscale[qscale];
 192     } else {
 193         return qscale << 1;
 194     }
 195 }
 196
 197 /* motion type (for MPEG-2) */
 198 #define MT_FIELD 1
 199 #define MT_FRAME 2
 200 #define MT_16X8  2
 201 #define MT_DMV   3
 202
 203 static int mpeg_decode_mb(MpegEncContext *s,
 204                           DCTELEM block[12][64])
 205 {
 206     int i, j, k, cbp, val, mb_type, motion_type;
 207     const int mb_block_count = 4 + (1<< s->chroma_format);
 208
 209     dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 210
 211     assert(s->mb_skipped==0);
 212
 213     if (s->mb_skip_run-- != 0) {
 214         if (s->pict_type == FF_P_TYPE) {
 215             s->mb_skipped = 1;
 216             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 217         } else {
 218             int mb_type;
 219
 220             if(s->mb_x)
 221                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
 222             else
 223                 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
 224             if(IS_INTRA(mb_type))
 225                 return -1;
 226
 227             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
 228                 mb_type | MB_TYPE_SKIP;
 229 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
 230
 231             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
 232                 s->mb_skipped = 1;
 233         }
 234
 235         return 0;
 236     }
 237
 238     switch(s->pict_type) {
 239     default:
 240     case FF_I_TYPE:
 241         if (get_bits1(&s->gb) == 0) {
 242             if (get_bits1(&s->gb) == 0){
 243                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
 244                 return -1;
 245             }
 246             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 247         } else {
 248             mb_type = MB_TYPE_INTRA;
 249         }
 250         break;
 251     case FF_P_TYPE:
 252         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 253         if (mb_type < 0){
 254             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 255             return -1;
 256         }
 257         mb_type = ptype2mb_type[ mb_type ];
 258         break;
 259     case FF_B_TYPE:
 260         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 261         if (mb_type < 0){
 262             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 263             return -1;
 264         }
 265         mb_type = btype2mb_type[ mb_type ];
 266         break;
 267     }
 268     dprintf(s->avctx, "mb_type=%x\n", mb_type);
 269 //    motion_type = 0; /* avoid warning */
 270     if (IS_INTRA(mb_type)) {
 271         s->dsp.clear_blocks(s->block[0]);
 272
 273         if(!s->chroma_y_shift){
 274             s->dsp.clear_blocks(s->block[6]);
 275         }
 276
 277         /* compute DCT type */
 278         if (s->picture_structure == PICT_FRAME && //FIXME add an interlaced_dct coded var?
 279             !s->frame_pred_frame_dct) {
 280             s->interlaced_dct = get_bits1(&s->gb);
 281         }
 282
 283         if (IS_QUANT(mb_type))
 284             s->qscale = get_qscale(s);
 285
 286         if (s->concealment_motion_vectors) {
 287             /* just parse them */
 288             if (s->picture_structure != PICT_FRAME)
 289                 skip_bits1(&s->gb); /* field select */
 290
 291             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 292                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 293             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 294                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 295
 296             skip_bits1(&s->gb); /* marker */
 297         }else
 298             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 299         s->mb_intra = 1;
 300 #if CONFIG_MPEG_XVMC_DECODER
 301         //if 1, we memcpy blocks in xvmcvideo
 302         if(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 #endif
 309
 310         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 311             if(s->flags2 & CODEC_FLAG2_FAST){
 312                 for(i=0;i<6;i++) {
 313                     mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
 314                 }
 315             }else{
 316                 for(i=0;i<mb_block_count;i++) {
 317                     if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
 318                         return -1;
 319                 }
 320             }
 321         } else {
 322             for(i=0;i<6;i++) {
 323                 if (ff_mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
 324                     return -1;
 325             }
 326         }
 327     } else {
 328         if (mb_type & MB_TYPE_ZERO_MV){
 329             assert(mb_type & MB_TYPE_CBP);
 330
 331             s->mv_dir = MV_DIR_FORWARD;
 332             if(s->picture_structure == PICT_FRAME){
 333                 if(!s->frame_pred_frame_dct)
 334                     s->interlaced_dct = get_bits1(&s->gb);
 335                 s->mv_type = MV_TYPE_16X16;
 336             }else{
 337                 s->mv_type = MV_TYPE_FIELD;
 338                 mb_type |= MB_TYPE_INTERLACED;
 339                 s->field_select[0][0]= s->picture_structure - 1;
 340             }
 341
 342             if (IS_QUANT(mb_type))
 343                 s->qscale = get_qscale(s);
 344
 345             s->last_mv[0][0][0] = 0;
 346             s->last_mv[0][0][1] = 0;
 347             s->last_mv[0][1][0] = 0;
 348             s->last_mv[0][1][1] = 0;
 349             s->mv[0][0][0] = 0;
 350             s->mv[0][0][1] = 0;
 351         }else{
 352             assert(mb_type & MB_TYPE_L0L1);
 353 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 354             /* get additional motion vector type */
 355             if (s->frame_pred_frame_dct)
 356                 motion_type = MT_FRAME;
 357             else{
 358                 motion_type = get_bits(&s->gb, 2);
 359                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 360                     s->interlaced_dct = get_bits1(&s->gb);
 361             }
 362
 363             if (IS_QUANT(mb_type))
 364                 s->qscale = get_qscale(s);
 365
 366             /* motion vectors */
 367             s->mv_dir= (mb_type>>13)&3;
 368             dprintf(s->avctx, "motion_type=%d\n", motion_type);
 369             switch(motion_type) {
 370             case MT_FRAME: /* or MT_16X8 */
 371                 if (s->picture_structure == PICT_FRAME) {
 372                     mb_type |= MB_TYPE_16x16;
 373                     s->mv_type = MV_TYPE_16X16;
 374                     for(i=0;i<2;i++) {
 375                         if (USES_LIST(mb_type, i)) {
 376                             /* MT_FRAME */
 377                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
 378                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
 379                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
 380                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
 381                             /* full_pel: only for MPEG-1 */
 382                             if (s->full_pel[i]){
 383                                 s->mv[i][0][0] <<= 1;
 384                                 s->mv[i][0][1] <<= 1;
 385                             }
 386                         }
 387                     }
 388                 } else {
 389                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 390                     s->mv_type = MV_TYPE_16X8;
 391                     for(i=0;i<2;i++) {
 392                         if (USES_LIST(mb_type, i)) {
 393                             /* MT_16X8 */
 394                             for(j=0;j<2;j++) {
 395                                 s->field_select[i][j] = get_bits1(&s->gb);
 396                                 for(k=0;k<2;k++) {
 397                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 398                                                              s->last_mv[i][j][k]);
 399                                     s->last_mv[i][j][k] = val;
 400                                     s->mv[i][j][k] = val;
 401                                 }
 402                             }
 403                         }
 404                     }
 405                 }
 406                 break;
 407             case MT_FIELD:
 408                 s->mv_type = MV_TYPE_FIELD;
 409                 if (s->picture_structure == PICT_FRAME) {
 410                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 411                     for(i=0;i<2;i++) {
 412                         if (USES_LIST(mb_type, i)) {
 413                             for(j=0;j<2;j++) {
 414                                 s->field_select[i][j] = get_bits1(&s->gb);
 415                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 416                                                          s->last_mv[i][j][0]);
 417                                 s->last_mv[i][j][0] = val;
 418                                 s->mv[i][j][0] = val;
 419                                 dprintf(s->avctx, "fmx=%d\n", val);
 420                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 421                                                          s->last_mv[i][j][1] >> 1);
 422                                 s->last_mv[i][j][1] = val << 1;
 423                                 s->mv[i][j][1] = val;
 424                                 dprintf(s->avctx, "fmy=%d\n", val);
 425                             }
 426                         }
 427                     }
 428                 } else {
 429                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 430                     for(i=0;i<2;i++) {
 431                         if (USES_LIST(mb_type, i)) {
 432                             s->field_select[i][0] = get_bits1(&s->gb);
 433                             for(k=0;k<2;k++) {
 434                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 435                                                          s->last_mv[i][0][k]);
 436                                 s->last_mv[i][0][k] = val;
 437                                 s->last_mv[i][1][k] = val;
 438                                 s->mv[i][0][k] = val;
 439                             }
 440                         }
 441                     }
 442                 }
 443                 break;
 444             case MT_DMV:
 445                 s->mv_type = MV_TYPE_DMV;
 446                 for(i=0;i<2;i++) {
 447                     if (USES_LIST(mb_type, i)) {
 448                         int dmx, dmy, mx, my, m;
 449                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 450                                                 s->last_mv[i][0][0]);
 451                         s->last_mv[i][0][0] = mx;
 452                         s->last_mv[i][1][0] = mx;
 453                         dmx = get_dmv(s);
 454                         my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 455                                                 s->last_mv[i][0][1] >> 1);
 456                         dmy = get_dmv(s);
 457
 458
 459                         s->last_mv[i][0][1] = my<<1;
 460                         s->last_mv[i][1][1] = my<<1;
 461
 462                         s->mv[i][0][0] = mx;
 463                         s->mv[i][0][1] = my;
 464                         s->mv[i][1][0] = mx;//not used
 465                         s->mv[i][1][1] = my;//not used
 466
 467                         if (s->picture_structure == PICT_FRAME) {
 468                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 469
 470                             //m = 1 + 2 * s->top_field_first;
 471                             m = s->top_field_first ? 1 : 3;
 472
 473                             /* top -> top pred */
 474                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 475                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 476                             m = 4 - m;
 477                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 478                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 479                         } else {
 480                             mb_type |= MB_TYPE_16x16;
 481
 482                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 483                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 484                             if(s->picture_structure == PICT_TOP_FIELD)
 485                                 s->mv[i][2][1]--;
 486                             else
 487                                 s->mv[i][2][1]++;
 488                         }
 489                     }
 490                 }
 491                 break;
 492             default:
 493                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 494                 return -1;
 495             }
 496         }
 497
 498         s->mb_intra = 0;
 499         if (HAS_CBP(mb_type)) {
 500             s->dsp.clear_blocks(s->block[0]);
 501
 502             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 503             if(mb_block_count > 6){
 504                  cbp<<= mb_block_count-6;
 505                  cbp |= get_bits(&s->gb, mb_block_count-6);
 506                  s->dsp.clear_blocks(s->block[6]);
 507             }
 508             if (cbp <= 0){
 509                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
 510                 return -1;
 511             }
 512
 513 #if CONFIG_MPEG_XVMC_DECODER
 514             //if 1, we memcpy blocks in xvmcvideo
 515             if(s->avctx->xvmc_acceleration > 1){
 516                 ff_xvmc_pack_pblocks(s,cbp);
 517                 if(s->swap_uv){
 518                     exchange_uv(s);
 519                 }
 520             }
 521 #endif
 522
 523             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 524                 if(s->flags2 & CODEC_FLAG2_FAST){
 525                     for(i=0;i<6;i++) {
 526                         if(cbp & 32) {
 527                             mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
 528                         } else {
 529                             s->block_last_index[i] = -1;
 530                         }
 531                         cbp+=cbp;
 532                     }
 533                 }else{
 534                     cbp<<= 12-mb_block_count;
 535
 536                     for(i=0;i<mb_block_count;i++) {
 537                         if ( cbp & (1<<11) ) {
 538                             if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
 539                                 return -1;
 540                         } else {
 541                             s->block_last_index[i] = -1;
 542                         }
 543                         cbp+=cbp;
 544                     }
 545                 }
 546             } else {
 547                 if(s->flags2 & CODEC_FLAG2_FAST){
 548                     for(i=0;i<6;i++) {
 549                         if (cbp & 32) {
 550                             mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
 551                         } else {
 552                             s->block_last_index[i] = -1;
 553                         }
 554                         cbp+=cbp;
 555                     }
 556                 }else{
 557                     for(i=0;i<6;i++) {
 558                         if (cbp & 32) {
 559                             if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
 560                                 return -1;
 561                         } else {
 562                             s->block_last_index[i] = -1;
 563                         }
 564                         cbp+=cbp;
 565                     }
 566                 }
 567             }
 568         }else{
 569             for(i=0;i<12;i++)
 570                 s->block_last_index[i] = -1;
 571         }
 572     }
 573
 574     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
 575
 576     return 0;
 577 }
 578
 579 /* as H.263, but only 17 codes */
 580 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 581 {
 582     int code, sign, val, l, shift;
 583
 584     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
 585     if (code == 0) {
 586         return pred;
 587     }
 588     if (code < 0) {
 589         return 0xffff;
 590     }
 591
 592     sign = get_bits1(&s->gb);
 593     shift = fcode - 1;
 594     val = code;
 595     if (shift) {
 596         val = (val - 1) << shift;
 597         val |= get_bits(&s->gb, shift);
 598         val++;
 599     }
 600     if (sign)
 601         val = -val;
 602     val += pred;
 603
 604     /* modulo decoding */
 605     l= INT_BIT - 5 - shift;
 606     val = (val<<l)>>l;
 607     return val;
 608 }
 609
 610 inline int ff_mpeg1_decode_block_intra(MpegEncContext *s,
 611                                DCTELEM *block,
 612                                int n)
 613 {
 614     int level, dc, diff, i, j, run;
 615     int component;
 616     RLTable *rl = &ff_rl_mpeg1;
 617     uint8_t * const scantable= s->intra_scantable.permutated;
 618     const uint16_t *quant_matrix= s->intra_matrix;
 619     const int qscale= s->qscale;
 620
 621     /* DC coefficient */
 622     component = (n <= 3 ? 0 : n - 4 + 1);
 623     diff = decode_dc(&s->gb, component);
 624     if (diff >= 0xffff)
 625         return -1;
 626     dc = s->last_dc[component];
 627     dc += diff;
 628     s->last_dc[component] = dc;
 629     block[0] = dc*quant_matrix[0];
 630     dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
 631     i = 0;
 632     {
 633         OPEN_READER(re, &s->gb);
 634         /* now quantify & encode AC coefficients */
 635         for(;;) {
 636             UPDATE_CACHE(re, &s->gb);
 637             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 638
 639             if(level == 127){
 640                 break;
 641             } else if(level != 0) {
 642                 i += run;
 643                 j = scantable[i];
 644                 level= (level*qscale*quant_matrix[j])>>4;
 645                 level= (level-1)|1;
 646                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 647                 LAST_SKIP_BITS(re, &s->gb, 1);
 648             } else {
 649                 /* escape */
 650                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 651                 UPDATE_CACHE(re, &s->gb);
 652                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 653                 if (level == -128) {
 654                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
 655                 } else if (level == 0) {
 656                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
 657                 }
 658                 i += run;
 659                 j = scantable[i];
 660                 if(level<0){
 661                     level= -level;
 662                     level= (level*qscale*quant_matrix[j])>>4;
 663                     level= (level-1)|1;
 664                     level= -level;
 665                 }else{
 666                     level= (level*qscale*quant_matrix[j])>>4;
 667                     level= (level-1)|1;
 668                 }
 669             }
 670             if (i > 63){
 671                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 672                 return -1;
 673             }
 674
 675             block[j] = level;
 676         }
 677         CLOSE_READER(re, &s->gb);
 678     }
 679     s->block_last_index[n] = i;
 680    return 0;
 681 }
 682
 683 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 684                                DCTELEM *block,
 685                                int n)
 686 {
 687     int level, i, j, run;
 688     RLTable *rl = &ff_rl_mpeg1;
 689     uint8_t * const scantable= s->intra_scantable.permutated;
 690     const uint16_t *quant_matrix= s->inter_matrix;
 691     const int qscale= s->qscale;
 692
 693     {
 694         OPEN_READER(re, &s->gb);
 695         i = -1;
 696         // special case for first coefficient, no need to add second VLC table
 697         UPDATE_CACHE(re, &s->gb);
 698         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 699             level= (3*qscale*quant_matrix[0])>>5;
 700             level= (level-1)|1;
 701             if(GET_CACHE(re, &s->gb)&0x40000000)
 702                 level= -level;
 703             block[0] = level;
 704             i++;
 705             SKIP_BITS(re, &s->gb, 2);
 706             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 707                 goto end;
 708         }
 709 #if MIN_CACHE_BITS < 19
 710         UPDATE_CACHE(re, &s->gb);
 711 #endif
 712         /* now quantify & encode AC coefficients */
 713         for(;;) {
 714             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 715
 716             if(level != 0) {
 717                 i += run;
 718                 j = scantable[i];
 719                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 720                 level= (level-1)|1;
 721                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 722                 SKIP_BITS(re, &s->gb, 1);
 723             } else {
 724                 /* escape */
 725                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 726                 UPDATE_CACHE(re, &s->gb);
 727                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 728                 if (level == -128) {
 729                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 730                 } else if (level == 0) {
 731                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 732                 }
 733                 i += run;
 734                 j = scantable[i];
 735                 if(level<0){
 736                     level= -level;
 737                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 738                     level= (level-1)|1;
 739                     level= -level;
 740                 }else{
 741                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 742                     level= (level-1)|1;
 743                 }
 744             }
 745             if (i > 63){
 746                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 747                 return -1;
 748             }
 749
 750             block[j] = level;
 751 #if MIN_CACHE_BITS < 19
 752             UPDATE_CACHE(re, &s->gb);
 753 #endif
 754             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 755                 break;
 756 #if MIN_CACHE_BITS >= 19
 757             UPDATE_CACHE(re, &s->gb);
 758 #endif
 759         }
 760 end:
 761         LAST_SKIP_BITS(re, &s->gb, 2);
 762         CLOSE_READER(re, &s->gb);
 763     }
 764     s->block_last_index[n] = i;
 765     return 0;
 766 }
 767
 768 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
 769 {
 770     int level, i, j, run;
 771     RLTable *rl = &ff_rl_mpeg1;
 772     uint8_t * const scantable= s->intra_scantable.permutated;
 773     const int qscale= s->qscale;
 774
 775     {
 776         OPEN_READER(re, &s->gb);
 777         i = -1;
 778         // special case for first coefficient, no need to add second VLC table
 779         UPDATE_CACHE(re, &s->gb);
 780         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 781             level= (3*qscale)>>1;
 782             level= (level-1)|1;
 783             if(GET_CACHE(re, &s->gb)&0x40000000)
 784                 level= -level;
 785             block[0] = level;
 786             i++;
 787             SKIP_BITS(re, &s->gb, 2);
 788             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 789                 goto end;
 790         }
 791 #if MIN_CACHE_BITS < 19
 792         UPDATE_CACHE(re, &s->gb);
 793 #endif
 794
 795         /* now quantify & encode AC coefficients */
 796         for(;;) {
 797             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 798
 799             if(level != 0) {
 800                 i += run;
 801                 j = scantable[i];
 802                 level= ((level*2+1)*qscale)>>1;
 803                 level= (level-1)|1;
 804                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 805                 SKIP_BITS(re, &s->gb, 1);
 806             } else {
 807                 /* escape */
 808                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 809                 UPDATE_CACHE(re, &s->gb);
 810                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 811                 if (level == -128) {
 812                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 813                 } else if (level == 0) {
 814                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 815                 }
 816                 i += run;
 817                 j = scantable[i];
 818                 if(level<0){
 819                     level= -level;
 820                     level= ((level*2+1)*qscale)>>1;
 821                     level= (level-1)|1;
 822                     level= -level;
 823                 }else{
 824                     level= ((level*2+1)*qscale)>>1;
 825                     level= (level-1)|1;
 826                 }
 827             }
 828
 829             block[j] = level;
 830 #if MIN_CACHE_BITS < 19
 831             UPDATE_CACHE(re, &s->gb);
 832 #endif
 833             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 834                 break;
 835 #if MIN_CACHE_BITS >= 19
 836             UPDATE_CACHE(re, &s->gb);
 837 #endif
 838         }
 839 end:
 840         LAST_SKIP_BITS(re, &s->gb, 2);
 841         CLOSE_READER(re, &s->gb);
 842     }
 843     s->block_last_index[n] = i;
 844     return 0;
 845 }
 846
 847
 848 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 849                                DCTELEM *block,
 850                                int n)
 851 {
 852     int level, i, j, run;
 853     RLTable *rl = &ff_rl_mpeg1;
 854     uint8_t * const scantable= s->intra_scantable.permutated;
 855     const uint16_t *quant_matrix;
 856     const int qscale= s->qscale;
 857     int mismatch;
 858
 859     mismatch = 1;
 860
 861     {
 862         OPEN_READER(re, &s->gb);
 863         i = -1;
 864         if (n < 4)
 865             quant_matrix = s->inter_matrix;
 866         else
 867             quant_matrix = s->chroma_inter_matrix;
 868
 869         // special case for first coefficient, no need to add second VLC table
 870         UPDATE_CACHE(re, &s->gb);
 871         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 872             level= (3*qscale*quant_matrix[0])>>5;
 873             if(GET_CACHE(re, &s->gb)&0x40000000)
 874                 level= -level;
 875             block[0] = level;
 876             mismatch ^= level;
 877             i++;
 878             SKIP_BITS(re, &s->gb, 2);
 879             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 880                 goto end;
 881         }
 882 #if MIN_CACHE_BITS < 19
 883         UPDATE_CACHE(re, &s->gb);
 884 #endif
 885
 886         /* now quantify & encode AC coefficients */
 887         for(;;) {
 888             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 889
 890             if(level != 0) {
 891                 i += run;
 892                 j = scantable[i];
 893                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 894                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 895                 SKIP_BITS(re, &s->gb, 1);
 896             } else {
 897                 /* escape */
 898                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 899                 UPDATE_CACHE(re, &s->gb);
 900                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 901
 902                 i += run;
 903                 j = scantable[i];
 904                 if(level<0){
 905                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
 906                     level= -level;
 907                 }else{
 908                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 909                 }
 910             }
 911             if (i > 63){
 912                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 913                 return -1;
 914             }
 915
 916             mismatch ^= level;
 917             block[j] = level;
 918 #if MIN_CACHE_BITS < 19
 919             UPDATE_CACHE(re, &s->gb);
 920 #endif
 921             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 922                 break;
 923 #if MIN_CACHE_BITS >= 19
 924             UPDATE_CACHE(re, &s->gb);
 925 #endif
 926         }
 927 end:
 928         LAST_SKIP_BITS(re, &s->gb, 2);
 929         CLOSE_READER(re, &s->gb);
 930     }
 931     block[63] ^= (mismatch & 1);
 932
 933     s->block_last_index[n] = i;
 934     return 0;
 935 }
 936
 937 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 938                                DCTELEM *block,
 939                                int n)
 940 {
 941     int level, i, j, run;
 942     RLTable *rl = &ff_rl_mpeg1;
 943     uint8_t * const scantable= s->intra_scantable.permutated;
 944     const int qscale= s->qscale;
 945     OPEN_READER(re, &s->gb);
 946     i = -1;
 947
 948     // special case for first coefficient, no need to add second VLC table
 949     UPDATE_CACHE(re, &s->gb);
 950     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 951         level= (3*qscale)>>1;
 952         if(GET_CACHE(re, &s->gb)&0x40000000)
 953             level= -level;
 954         block[0] = level;
 955         i++;
 956         SKIP_BITS(re, &s->gb, 2);
 957         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 958             goto end;
 959     }
 960 #if MIN_CACHE_BITS < 19
 961     UPDATE_CACHE(re, &s->gb);
 962 #endif
 963
 964     /* now quantify & encode AC coefficients */
 965     for(;;) {
 966         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 967
 968         if(level != 0) {
 969             i += run;
 970             j = scantable[i];
 971             level= ((level*2+1)*qscale)>>1;
 972             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 973             SKIP_BITS(re, &s->gb, 1);
 974         } else {
 975             /* escape */
 976             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 977             UPDATE_CACHE(re, &s->gb);
 978             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 979
 980             i += run;
 981             j = scantable[i];
 982             if(level<0){
 983                 level= ((-level*2+1)*qscale)>>1;
 984                 level= -level;
 985             }else{
 986                 level= ((level*2+1)*qscale)>>1;
 987             }
 988         }
 989
 990         block[j] = level;
 991 #if MIN_CACHE_BITS < 19
 992         UPDATE_CACHE(re, &s->gb);
 993 #endif
 994         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 995             break;
 996 #if MIN_CACHE_BITS >=19
 997         UPDATE_CACHE(re, &s->gb);
 998 #endif
 999     }
1000 end:
1001     LAST_SKIP_BITS(re, &s->gb, 2);
1002     CLOSE_READER(re, &s->gb);
1003     s->block_last_index[n] = i;
1004     return 0;
1005 }
1006
1007
1008 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1009                                DCTELEM *block,
1010                                int n)
1011 {
1012     int level, dc, diff, i, j, run;
1013     int component;
1014     RLTable *rl;
1015     uint8_t * const scantable= s->intra_scantable.permutated;
1016     const uint16_t *quant_matrix;
1017     const int qscale= s->qscale;
1018     int mismatch;
1019
1020     /* DC coefficient */
1021     if (n < 4){
1022         quant_matrix = s->intra_matrix;
1023         component = 0;
1024     }else{
1025         quant_matrix = s->chroma_intra_matrix;
1026         component = (n&1) + 1;
1027     }
1028     diff = decode_dc(&s->gb, component);
1029     if (diff >= 0xffff)
1030         return -1;
1031     dc = s->last_dc[component];
1032     dc += diff;
1033     s->last_dc[component] = dc;
1034     block[0] = dc << (3 - s->intra_dc_precision);
1035     dprintf(s->avctx, "dc=%d\n", block[0]);
1036     mismatch = block[0] ^ 1;
1037     i = 0;
1038     if (s->intra_vlc_format)
1039         rl = &ff_rl_mpeg2;
1040     else
1041         rl = &ff_rl_mpeg1;
1042
1043     {
1044         OPEN_READER(re, &s->gb);
1045         /* now quantify & encode AC coefficients */
1046         for(;;) {
1047             UPDATE_CACHE(re, &s->gb);
1048             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1049
1050             if(level == 127){
1051                 break;
1052             } else if(level != 0) {
1053                 i += run;
1054                 j = scantable[i];
1055                 level= (level*qscale*quant_matrix[j])>>4;
1056                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1057                 LAST_SKIP_BITS(re, &s->gb, 1);
1058             } else {
1059                 /* escape */
1060                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1061                 UPDATE_CACHE(re, &s->gb);
1062                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1063                 i += run;
1064                 j = scantable[i];
1065                 if(level<0){
1066                     level= (-level*qscale*quant_matrix[j])>>4;
1067                     level= -level;
1068                 }else{
1069                     level= (level*qscale*quant_matrix[j])>>4;
1070                 }
1071             }
1072             if (i > 63){
1073                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1074                 return -1;
1075             }
1076
1077             mismatch^= level;
1078             block[j] = level;
1079         }
1080         CLOSE_READER(re, &s->gb);
1081     }
1082     block[63]^= mismatch&1;
1083
1084     s->block_last_index[n] = i;
1085     return 0;
1086 }
1087
1088 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1089                                DCTELEM *block,
1090                                int n)
1091 {
1092     int level, dc, diff, j, run;
1093     int component;
1094     RLTable *rl;
1095     uint8_t * scantable= s->intra_scantable.permutated;
1096     const uint16_t *quant_matrix;
1097     const int qscale= s->qscale;
1098
1099     /* DC coefficient */
1100     if (n < 4){
1101         quant_matrix = s->intra_matrix;
1102         component = 0;
1103     }else{
1104         quant_matrix = s->chroma_intra_matrix;
1105         component = (n&1) + 1;
1106     }
1107     diff = decode_dc(&s->gb, component);
1108     if (diff >= 0xffff)
1109         return -1;
1110     dc = s->last_dc[component];
1111     dc += diff;
1112     s->last_dc[component] = dc;
1113     block[0] = dc << (3 - s->intra_dc_precision);
1114     if (s->intra_vlc_format)
1115         rl = &ff_rl_mpeg2;
1116     else
1117         rl = &ff_rl_mpeg1;
1118
1119     {
1120         OPEN_READER(re, &s->gb);
1121         /* now quantify & encode AC coefficients */
1122         for(;;) {
1123             UPDATE_CACHE(re, &s->gb);
1124             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1125
1126             if(level == 127){
1127                 break;
1128             } else if(level != 0) {
1129                 scantable += run;
1130                 j = *scantable;
1131                 level= (level*qscale*quant_matrix[j])>>4;
1132                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1133                 LAST_SKIP_BITS(re, &s->gb, 1);
1134             } else {
1135                 /* escape */
1136                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1137                 UPDATE_CACHE(re, &s->gb);
1138                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1139                 scantable += run;
1140                 j = *scantable;
1141                 if(level<0){
1142                     level= (-level*qscale*quant_matrix[j])>>4;
1143                     level= -level;
1144                 }else{
1145                     level= (level*qscale*quant_matrix[j])>>4;
1146                 }
1147             }
1148
1149             block[j] = level;
1150         }
1151         CLOSE_READER(re, &s->gb);
1152     }
1153
1154     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1155     return 0;
1156 }
1157
1158 typedef struct Mpeg1Context {
1159     MpegEncContext mpeg_enc_ctx;
1160     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1161     int repeat_field; /* true if we must repeat the field */
1162     AVPanScan pan_scan; /** some temporary storage for the panscan */
1163     int slice_count;
1164     int swap_uv;//indicate VCR2
1165     int save_aspect_info;
1166     int save_width, save_height;
1167     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1168
1169 } Mpeg1Context;
1170
1171 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1172 {
1173     Mpeg1Context *s = avctx->priv_data;
1174     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1175     int i;
1176
1177     /* we need some permutation to store matrices,
1178      * until MPV_common_init() sets the real permutation. */
1179     for(i=0;i<64;i++)
1180        s2->dsp.idct_permutation[i]=i;
1181
1182     MPV_decode_defaults(s2);
1183
1184     s->mpeg_enc_ctx.avctx= avctx;
1185     s->mpeg_enc_ctx.flags= avctx->flags;
1186     s->mpeg_enc_ctx.flags2= avctx->flags2;
1187     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1188     ff_mpeg12_init_vlcs();
1189
1190     s->mpeg_enc_ctx_allocated = 0;
1191     s->mpeg_enc_ctx.picture_number = 0;
1192     s->repeat_field = 0;
1193     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1194     return 0;
1195 }
1196
1197 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1198                                      const uint8_t *new_perm){
1199     uint16_t temp_matrix[64];
1200     int i;
1201
1202     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1203
1204     for(i=0;i<64;i++){
1205         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1206     }
1207 }
1208
1209 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx){
1210     Mpeg1Context *s1 = avctx->priv_data;
1211     MpegEncContext *s = &s1->mpeg_enc_ctx;
1212
1213     if(avctx->xvmc_acceleration)
1214         return avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1215     else if(avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU){
1216         if(avctx->codec_id == CODEC_ID_MPEG1VIDEO)
1217             return PIX_FMT_VDPAU_MPEG1;
1218         else
1219             return PIX_FMT_VDPAU_MPEG2;
1220     }else{
1221         if(s->chroma_format <  2)
1222             return PIX_FMT_YUV420P;
1223         else if(s->chroma_format == 2)
1224             return PIX_FMT_YUV422P;
1225         else
1226             return PIX_FMT_YUV444P;
1227     }
1228 }
1229
1230 /* Call this function when we know all parameters.
1231  * It may be called in different places for MPEG-1 and MPEG-2. */
1232 static int mpeg_decode_postinit(AVCodecContext *avctx){
1233     Mpeg1Context *s1 = avctx->priv_data;
1234     MpegEncContext *s = &s1->mpeg_enc_ctx;
1235     uint8_t old_permutation[64];
1236
1237     if (
1238         (s1->mpeg_enc_ctx_allocated == 0)||
1239         avctx->coded_width  != s->width ||
1240         avctx->coded_height != s->height||
1241         s1->save_width != s->width ||
1242         s1->save_height != s->height ||
1243         s1->save_aspect_info != s->aspect_ratio_info||
1244         0)
1245     {
1246
1247         if (s1->mpeg_enc_ctx_allocated) {
1248             ParseContext pc= s->parse_context;
1249             s->parse_context.buffer=0;
1250             MPV_common_end(s);
1251             s->parse_context= pc;
1252         }
1253
1254         if( (s->width == 0 )||(s->height == 0))
1255             return -2;
1256
1257         avcodec_set_dimensions(avctx, s->width, s->height);
1258         avctx->bit_rate = s->bit_rate;
1259         s1->save_aspect_info = s->aspect_ratio_info;
1260         s1->save_width = s->width;
1261         s1->save_height = s->height;
1262
1263         /* low_delay may be forced, in this case we will have B-frames
1264          * that behave like P-frames. */
1265         avctx->has_b_frames = !(s->low_delay);
1266
1267         assert((avctx->sub_id==1) == (avctx->codec_id==CODEC_ID_MPEG1VIDEO));
1268         if(avctx->codec_id==CODEC_ID_MPEG1VIDEO){
1269             //MPEG-1 fps
1270             avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1271             avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1272             //MPEG-1 aspect
1273             avctx->sample_aspect_ratio= av_d2q(
1274                     1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1275
1276         }else{//MPEG-2
1277         //MPEG-2 fps
1278             av_reduce(
1279                 &s->avctx->time_base.den,
1280                 &s->avctx->time_base.num,
1281                 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1282                 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1283                 1<<30);
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         //until then pix_fmt may be changed right after codec init
1309         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
1310             s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
1311             if( avctx->idct_algo == FF_IDCT_AUTO )
1312                 avctx->idct_algo = FF_IDCT_SIMPLE;
1313
1314         /* Quantization matrices may need reordering
1315          * if DCT permutation is changed. */
1316         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1317
1318         if (MPV_common_init(s) < 0)
1319             return -2;
1320
1321         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
1322         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
1323         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1324         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1325
1326         s1->mpeg_enc_ctx_allocated = 1;
1327     }
1328     return 0;
1329 }
1330
1331 static int mpeg1_decode_picture(AVCodecContext *avctx,
1332                                 const uint8_t *buf, int buf_size)
1333 {
1334     Mpeg1Context *s1 = avctx->priv_data;
1335     MpegEncContext *s = &s1->mpeg_enc_ctx;
1336     int ref, f_code, vbv_delay;
1337
1338     if(mpeg_decode_postinit(s->avctx) < 0)
1339        return -2;
1340
1341     init_get_bits(&s->gb, buf, buf_size*8);
1342
1343     ref = get_bits(&s->gb, 10); /* temporal ref */
1344     s->pict_type = get_bits(&s->gb, 3);
1345     if(s->pict_type == 0 || s->pict_type > 3)
1346         return -1;
1347
1348     vbv_delay= get_bits(&s->gb, 16);
1349     if (s->pict_type == FF_P_TYPE || s->pict_type == FF_B_TYPE) {
1350         s->full_pel[0] = get_bits1(&s->gb);
1351         f_code = get_bits(&s->gb, 3);
1352         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1353             return -1;
1354         s->mpeg_f_code[0][0] = f_code;
1355         s->mpeg_f_code[0][1] = f_code;
1356     }
1357     if (s->pict_type == FF_B_TYPE) {
1358         s->full_pel[1] = get_bits1(&s->gb);
1359         f_code = get_bits(&s->gb, 3);
1360         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1361             return -1;
1362         s->mpeg_f_code[1][0] = f_code;
1363         s->mpeg_f_code[1][1] = f_code;
1364     }
1365     s->current_picture.pict_type= s->pict_type;
1366     s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1367
1368     if(avctx->debug & FF_DEBUG_PICT_INFO)
1369         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1370
1371     s->y_dc_scale = 8;
1372     s->c_dc_scale = 8;
1373     s->first_slice = 1;
1374     return 0;
1375 }
1376
1377 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1378 {
1379     MpegEncContext *s= &s1->mpeg_enc_ctx;
1380     int horiz_size_ext, vert_size_ext;
1381     int bit_rate_ext;
1382
1383     skip_bits(&s->gb, 1); /* profile and level esc*/
1384     s->avctx->profile= get_bits(&s->gb, 3);
1385     s->avctx->level= get_bits(&s->gb, 4);
1386     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1387     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1388     horiz_size_ext = get_bits(&s->gb, 2);
1389     vert_size_ext = get_bits(&s->gb, 2);
1390     s->width |= (horiz_size_ext << 12);
1391     s->height |= (vert_size_ext << 12);
1392     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1393     s->bit_rate += (bit_rate_ext << 18) * 400;
1394     skip_bits1(&s->gb); /* marker */
1395     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1396
1397     s->low_delay = get_bits1(&s->gb);
1398     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1399
1400     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1401     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1402
1403     dprintf(s->avctx, "sequence extension\n");
1404     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1405     s->avctx->sub_id = 2; /* indicates MPEG-2 found */
1406
1407     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1408         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1409                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1410
1411 }
1412
1413 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1414 {
1415     MpegEncContext *s= &s1->mpeg_enc_ctx;
1416     int color_description, w, h;
1417
1418     skip_bits(&s->gb, 3); /* video format */
1419     color_description= get_bits1(&s->gb);
1420     if(color_description){
1421         skip_bits(&s->gb, 8); /* color primaries */
1422         skip_bits(&s->gb, 8); /* transfer_characteristics */
1423         skip_bits(&s->gb, 8); /* matrix_coefficients */
1424     }
1425     w= get_bits(&s->gb, 14);
1426     skip_bits(&s->gb, 1); //marker
1427     h= get_bits(&s->gb, 14);
1428     skip_bits(&s->gb, 1); //marker
1429
1430     s1->pan_scan.width= 16*w;
1431     s1->pan_scan.height=16*h;
1432
1433     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1434         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1435 }
1436
1437 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1438 {
1439     MpegEncContext *s= &s1->mpeg_enc_ctx;
1440     int i,nofco;
1441
1442     nofco = 1;
1443     if(s->progressive_sequence){
1444         if(s->repeat_first_field){
1445             nofco++;
1446             if(s->top_field_first)
1447                 nofco++;
1448         }
1449     }else{
1450         if(s->picture_structure == PICT_FRAME){
1451             nofco++;
1452             if(s->repeat_first_field)
1453                 nofco++;
1454         }
1455     }
1456     for(i=0; i<nofco; i++){
1457         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1458         skip_bits(&s->gb, 1); //marker
1459         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1460         skip_bits(&s->gb, 1); //marker
1461     }
1462
1463     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1464         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1465             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1466             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1467             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1468         );
1469 }
1470
1471 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1472 {
1473     int i, v, j;
1474
1475     dprintf(s->avctx, "matrix extension\n");
1476
1477     if (get_bits1(&s->gb)) {
1478         for(i=0;i<64;i++) {
1479             v = get_bits(&s->gb, 8);
1480             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1481             s->intra_matrix[j] = v;
1482             s->chroma_intra_matrix[j] = v;
1483         }
1484     }
1485     if (get_bits1(&s->gb)) {
1486         for(i=0;i<64;i++) {
1487             v = get_bits(&s->gb, 8);
1488             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1489             s->inter_matrix[j] = v;
1490             s->chroma_inter_matrix[j] = v;
1491         }
1492     }
1493     if (get_bits1(&s->gb)) {
1494         for(i=0;i<64;i++) {
1495             v = get_bits(&s->gb, 8);
1496             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1497             s->chroma_intra_matrix[j] = v;
1498         }
1499     }
1500     if (get_bits1(&s->gb)) {
1501         for(i=0;i<64;i++) {
1502             v = get_bits(&s->gb, 8);
1503             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1504             s->chroma_inter_matrix[j] = v;
1505         }
1506     }
1507 }
1508
1509 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1510 {
1511     MpegEncContext *s= &s1->mpeg_enc_ctx;
1512
1513     s->full_pel[0] = s->full_pel[1] = 0;
1514     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1515     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1516     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1517     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1518     if(!s->pict_type && s1->mpeg_enc_ctx_allocated){
1519         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1520         if(s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1]==15){
1521             if(s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1522                 s->pict_type= FF_I_TYPE;
1523             else
1524                 s->pict_type= FF_P_TYPE;
1525         }else
1526             s->pict_type= FF_B_TYPE;
1527         s->current_picture.pict_type= s->pict_type;
1528         s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1529         s->first_slice= 1;
1530     }
1531     s->intra_dc_precision = get_bits(&s->gb, 2);
1532     s->picture_structure = get_bits(&s->gb, 2);
1533     s->top_field_first = get_bits1(&s->gb);
1534     s->frame_pred_frame_dct = get_bits1(&s->gb);
1535     s->concealment_motion_vectors = get_bits1(&s->gb);
1536     s->q_scale_type = get_bits1(&s->gb);
1537     s->intra_vlc_format = get_bits1(&s->gb);
1538     s->alternate_scan = get_bits1(&s->gb);
1539     s->repeat_first_field = get_bits1(&s->gb);
1540     s->chroma_420_type = get_bits1(&s->gb);
1541     s->progressive_frame = get_bits1(&s->gb);
1542
1543     if(s->picture_structure == PICT_FRAME){
1544         s->first_field=0;
1545         s->v_edge_pos= 16*s->mb_height;
1546     }else{
1547         s->first_field ^= 1;
1548         s->v_edge_pos=  8*s->mb_height;
1549         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1550     }
1551
1552     if(s->alternate_scan){
1553         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1554         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1555     }else{
1556         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1557         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1558     }
1559
1560     /* composite display not parsed */
1561     dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1562     dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1563     dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1564     dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1565     dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1566     dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1567     dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1568     dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1569     dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1570 }
1571
1572 static void mpeg_decode_extension(AVCodecContext *avctx,
1573                                   const uint8_t *buf, int buf_size)
1574 {
1575     Mpeg1Context *s1 = avctx->priv_data;
1576     MpegEncContext *s = &s1->mpeg_enc_ctx;
1577     int ext_type;
1578
1579     init_get_bits(&s->gb, buf, buf_size*8);
1580
1581     ext_type = get_bits(&s->gb, 4);
1582     switch(ext_type) {
1583     case 0x1:
1584         mpeg_decode_sequence_extension(s1);
1585         break;
1586     case 0x2:
1587         mpeg_decode_sequence_display_extension(s1);
1588         break;
1589     case 0x3:
1590         mpeg_decode_quant_matrix_extension(s);
1591         break;
1592     case 0x7:
1593         mpeg_decode_picture_display_extension(s1);
1594         break;
1595     case 0x8:
1596         mpeg_decode_picture_coding_extension(s1);
1597         break;
1598     }
1599 }
1600
1601 static void exchange_uv(MpegEncContext *s){
1602     short * tmp = s->pblocks[4];
1603     s->pblocks[4] = s->pblocks[5];
1604     s->pblocks[5] = tmp;
1605 }
1606
1607 static int mpeg_field_start(MpegEncContext *s){
1608     AVCodecContext *avctx= s->avctx;
1609     Mpeg1Context *s1 = (Mpeg1Context*)s;
1610
1611     /* start frame decoding */
1612     if(s->first_field || s->picture_structure==PICT_FRAME){
1613         if(MPV_frame_start(s, avctx) < 0)
1614             return -1;
1615
1616         ff_er_frame_start(s);
1617
1618         /* first check if we must repeat the frame */
1619         s->current_picture_ptr->repeat_pict = 0;
1620         if (s->repeat_first_field) {
1621             if (s->progressive_sequence) {
1622                 if (s->top_field_first)
1623                     s->current_picture_ptr->repeat_pict = 4;
1624                 else
1625                     s->current_picture_ptr->repeat_pict = 2;
1626             } else if (s->progressive_frame) {
1627                 s->current_picture_ptr->repeat_pict = 1;
1628             }
1629         }
1630
1631         *s->current_picture_ptr->pan_scan= s1->pan_scan;
1632     }else{ //second field
1633             int i;
1634
1635             if(!s->current_picture_ptr){
1636                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1637                 return -1;
1638             }
1639
1640             for(i=0; i<4; i++){
1641                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1642                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1643                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1644                 }
1645             }
1646     }
1647 #if CONFIG_MPEG_XVMC_DECODER
1648 // MPV_frame_start will call this function too,
1649 // but we need to call it on every field
1650     if(s->avctx->xvmc_acceleration)
1651         if( ff_xvmc_field_start(s,avctx) < 0)
1652             return -1;
1653 #endif
1654
1655     return 0;
1656 }
1657
1658 #define DECODE_SLICE_ERROR -1
1659 #define DECODE_SLICE_OK 0
1660
1661 /**
1662  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1663  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1664  *         DECODE_SLICE_OK if this slice is ok<br>
1665  */
1666 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1667                              const uint8_t **buf, int buf_size)
1668 {
1669     MpegEncContext *s = &s1->mpeg_enc_ctx;
1670     AVCodecContext *avctx= s->avctx;
1671     const int field_pic= s->picture_structure != PICT_FRAME;
1672     const int lowres= s->avctx->lowres;
1673
1674     s->resync_mb_x=
1675     s->resync_mb_y= -1;
1676
1677     if (mb_y<<field_pic >= s->mb_height){
1678         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
1679         return -1;
1680     }
1681
1682     init_get_bits(&s->gb, *buf, buf_size*8);
1683
1684     ff_mpeg1_clean_buffers(s);
1685     s->interlaced_dct = 0;
1686
1687     s->qscale = get_qscale(s);
1688
1689     if(s->qscale == 0){
1690         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1691         return -1;
1692     }
1693
1694     /* extra slice info */
1695     while (get_bits1(&s->gb) != 0) {
1696         skip_bits(&s->gb, 8);
1697     }
1698
1699     s->mb_x=0;
1700
1701     for(;;) {
1702         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1703         if (code < 0){
1704             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1705             return -1;
1706         }
1707         if (code >= 33) {
1708             if (code == 33) {
1709                 s->mb_x += 33;
1710             }
1711             /* otherwise, stuffing, nothing to do */
1712         } else {
1713             s->mb_x += code;
1714             break;
1715         }
1716     }
1717     if(s->mb_x >= (unsigned)s->mb_width){
1718         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1719         return -1;
1720     }
1721
1722     s->resync_mb_x= s->mb_x;
1723     s->resync_mb_y= s->mb_y= mb_y;
1724     s->mb_skip_run= 0;
1725     ff_init_block_index(s);
1726
1727     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1728         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1729              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",
1730                  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],
1731                  s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
1732                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1733                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1734                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1735         }
1736     }
1737
1738     for(;;) {
1739 #if CONFIG_MPEG_XVMC_DECODER
1740         //If 1, we memcpy blocks in xvmcvideo.
1741         if(s->avctx->xvmc_acceleration > 1)
1742             ff_xvmc_init_block(s);//set s->block
1743 #endif
1744
1745         if(mpeg_decode_mb(s, s->block) < 0)
1746             return -1;
1747
1748         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1749             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
1750             int xy = s->mb_x*2 + s->mb_y*2*wrap;
1751             int motion_x, motion_y, dir, i;
1752             if(field_pic && !s->first_field)
1753                 xy += wrap/2;
1754
1755             for(i=0; i<2; i++){
1756                 for(dir=0; dir<2; dir++){
1757                     if (s->mb_intra || (dir==1 && s->pict_type != FF_B_TYPE)) {
1758                         motion_x = motion_y = 0;
1759                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1760                         motion_x = s->mv[dir][0][0];
1761                         motion_y = s->mv[dir][0][1];
1762                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1763                         motion_x = s->mv[dir][i][0];
1764                         motion_y = s->mv[dir][i][1];
1765                     }
1766
1767                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1768                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1769                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1770                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1771                     s->current_picture.ref_index [dir][xy    ]=
1772                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
1773                     assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1774                 }
1775                 xy += wrap;
1776             }
1777         }
1778
1779         s->dest[0] += 16 >> lowres;
1780         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1781         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1782
1783         MPV_decode_mb(s, s->block);
1784
1785         if (++s->mb_x >= s->mb_width) {
1786             const int mb_size= 16>>s->avctx->lowres;
1787
1788             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
1789
1790             s->mb_x = 0;
1791             s->mb_y++;
1792
1793             if(s->mb_y<<field_pic >= s->mb_height){
1794                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1795                 int is_d10= s->chroma_format==2 && s->pict_type==FF_I_TYPE && avctx->profile==0 && avctx->level==5
1796                             && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1797                             && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1798
1799                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1800                    || (avctx->error_recognition >= FF_ER_AGGRESSIVE && left>8)){
1801                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1802                     return -1;
1803                 }else
1804                     goto eos;
1805             }
1806
1807             ff_init_block_index(s);
1808         }
1809
1810         /* skip mb handling */
1811         if (s->mb_skip_run == -1) {
1812             /* read increment again */
1813             s->mb_skip_run = 0;
1814             for(;;) {
1815                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1816                 if (code < 0){
1817                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1818                     return -1;
1819                 }
1820                 if (code >= 33) {
1821                     if (code == 33) {
1822                         s->mb_skip_run += 33;
1823                     }else if(code == 35){
1824                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1825                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1826                             return -1;
1827                         }
1828                         goto eos; /* end of slice */
1829                     }
1830                     /* otherwise, stuffing, nothing to do */
1831                 } else {
1832                     s->mb_skip_run += code;
1833                     break;
1834                 }
1835             }
1836             if(s->mb_skip_run){
1837                 int i;
1838                 if(s->pict_type == FF_I_TYPE){
1839                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1840                     return -1;
1841                 }
1842
1843                 /* skip mb */
1844                 s->mb_intra = 0;
1845                 for(i=0;i<12;i++)
1846                     s->block_last_index[i] = -1;
1847                 if(s->picture_structure == PICT_FRAME)
1848                     s->mv_type = MV_TYPE_16X16;
1849                 else
1850                     s->mv_type = MV_TYPE_FIELD;
1851                 if (s->pict_type == FF_P_TYPE) {
1852                     /* if P type, zero motion vector is implied */
1853                     s->mv_dir = MV_DIR_FORWARD;
1854                     s->mv[0][0][0] = s->mv[0][0][1] = 0;
1855                     s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1856                     s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1857                     s->field_select[0][0]= s->picture_structure - 1;
1858                 } else {
1859                     /* if B type, reuse previous vectors and directions */
1860                     s->mv[0][0][0] = s->last_mv[0][0][0];
1861                     s->mv[0][0][1] = s->last_mv[0][0][1];
1862                     s->mv[1][0][0] = s->last_mv[1][0][0];
1863                     s->mv[1][0][1] = s->last_mv[1][0][1];
1864                 }
1865             }
1866         }
1867     }
1868 eos: // end of slice
1869     *buf += (get_bits_count(&s->gb)-1)/8;
1870 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1871     return 0;
1872 }
1873
1874 static int slice_decode_thread(AVCodecContext *c, void *arg){
1875     MpegEncContext *s= *(void**)arg;
1876     const uint8_t *buf= s->gb.buffer;
1877     int mb_y= s->start_mb_y;
1878
1879     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
1880
1881     for(;;){
1882         uint32_t start_code;
1883         int ret;
1884
1885         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1886         emms_c();
1887 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1888 //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);
1889         if(ret < 0){
1890             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1891                 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);
1892         }else{
1893             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);
1894         }
1895
1896         if(s->mb_y == s->end_mb_y)
1897             return 0;
1898
1899         start_code= -1;
1900         buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1901         mb_y= start_code - SLICE_MIN_START_CODE;
1902         if(mb_y < 0 || mb_y >= s->end_mb_y)
1903             return -1;
1904     }
1905
1906     return 0; //not reached
1907 }
1908
1909 /**
1910  * Handles slice ends.
1911  * @return 1 if it seems to be the last slice
1912  */
1913 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1914 {
1915     Mpeg1Context *s1 = avctx->priv_data;
1916     MpegEncContext *s = &s1->mpeg_enc_ctx;
1917
1918     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1919         return 0;
1920
1921 #if CONFIG_MPEG_XVMC_DECODER
1922     if(s->avctx->xvmc_acceleration)
1923         ff_xvmc_field_end(s);
1924 #endif
1925     /* end of slice reached */
1926     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1927         /* end of image */
1928
1929         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1930
1931         ff_er_frame_end(s);
1932
1933         MPV_frame_end(s);
1934
1935         if (s->pict_type == FF_B_TYPE || s->low_delay) {
1936             *pict= *(AVFrame*)s->current_picture_ptr;
1937             ff_print_debug_info(s, pict);
1938         } else {
1939             s->picture_number++;
1940             /* latency of 1 frame for I- and P-frames */
1941             /* XXX: use another variable than picture_number */
1942             if (s->last_picture_ptr != NULL) {
1943                 *pict= *(AVFrame*)s->last_picture_ptr;
1944                  ff_print_debug_info(s, pict);
1945             }
1946         }
1947
1948         return 1;
1949     } else {
1950         return 0;
1951     }
1952 }
1953
1954 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1955                                  const uint8_t *buf, int buf_size)
1956 {
1957     Mpeg1Context *s1 = avctx->priv_data;
1958     MpegEncContext *s = &s1->mpeg_enc_ctx;
1959     int width,height;
1960     int i, v, j;
1961
1962     init_get_bits(&s->gb, buf, buf_size*8);
1963
1964     width = get_bits(&s->gb, 12);
1965     height = get_bits(&s->gb, 12);
1966     if (width <= 0 || height <= 0)
1967         return -1;
1968     s->aspect_ratio_info= get_bits(&s->gb, 4);
1969     if (s->aspect_ratio_info == 0) {
1970         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1971         if (avctx->error_recognition >= FF_ER_COMPLIANT)
1972             return -1;
1973     }
1974     s->frame_rate_index = get_bits(&s->gb, 4);
1975     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1976         return -1;
1977     s->bit_rate = get_bits(&s->gb, 18) * 400;
1978     if (get_bits1(&s->gb) == 0) /* marker */
1979         return -1;
1980     s->width = width;
1981     s->height = height;
1982
1983     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
1984     skip_bits(&s->gb, 1);
1985
1986     /* get matrix */
1987     if (get_bits1(&s->gb)) {
1988         for(i=0;i<64;i++) {
1989             v = get_bits(&s->gb, 8);
1990             if(v==0){
1991                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
1992                 return -1;
1993             }
1994             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1995             s->intra_matrix[j] = v;
1996             s->chroma_intra_matrix[j] = v;
1997         }
1998 #ifdef DEBUG
1999         dprintf(s->avctx, "intra matrix present\n");
2000         for(i=0;i<64;i++)
2001             dprintf(s->avctx, " %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
2002         dprintf(s->avctx, "\n");
2003 #endif
2004     } else {
2005         for(i=0;i<64;i++) {
2006             j = s->dsp.idct_permutation[i];
2007             v = ff_mpeg1_default_intra_matrix[i];
2008             s->intra_matrix[j] = v;
2009             s->chroma_intra_matrix[j] = v;
2010         }
2011     }
2012     if (get_bits1(&s->gb)) {
2013         for(i=0;i<64;i++) {
2014             v = get_bits(&s->gb, 8);
2015             if(v==0){
2016                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2017                 return -1;
2018             }
2019             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2020             s->inter_matrix[j] = v;
2021             s->chroma_inter_matrix[j] = v;
2022         }
2023 #ifdef DEBUG
2024         dprintf(s->avctx, "non-intra matrix present\n");
2025         for(i=0;i<64;i++)
2026             dprintf(s->avctx, " %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
2027         dprintf(s->avctx, "\n");
2028 #endif
2029     } else {
2030         for(i=0;i<64;i++) {
2031             int j= s->dsp.idct_permutation[i];
2032             v = ff_mpeg1_default_non_intra_matrix[i];
2033             s->inter_matrix[j] = v;
2034             s->chroma_inter_matrix[j] = v;
2035         }
2036     }
2037
2038     if(show_bits(&s->gb, 23) != 0){
2039         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2040         return -1;
2041     }
2042
2043     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
2044     s->progressive_sequence = 1;
2045     s->progressive_frame = 1;
2046     s->picture_structure = PICT_FRAME;
2047     s->frame_pred_frame_dct = 1;
2048     s->chroma_format = 1;
2049     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2050     avctx->sub_id = 1; /* indicates MPEG-1 */
2051     s->out_format = FMT_MPEG1;
2052     s->swap_uv = 0;//AFAIK VCR2 does not have SEQ_HEADER
2053     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2054
2055     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2056         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2057                s->avctx->rc_buffer_size, s->bit_rate);
2058
2059     return 0;
2060 }
2061
2062 static int vcr2_init_sequence(AVCodecContext *avctx)
2063 {
2064     Mpeg1Context *s1 = avctx->priv_data;
2065     MpegEncContext *s = &s1->mpeg_enc_ctx;
2066     int i, v;
2067
2068     /* start new MPEG-1 context decoding */
2069     s->out_format = FMT_MPEG1;
2070     if (s1->mpeg_enc_ctx_allocated) {
2071         MPV_common_end(s);
2072     }
2073     s->width  = avctx->coded_width;
2074     s->height = avctx->coded_height;
2075     avctx->has_b_frames= 0; //true?
2076     s->low_delay= 1;
2077
2078     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2079
2080     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
2081         s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
2082         if( avctx->idct_algo == FF_IDCT_AUTO )
2083             avctx->idct_algo = FF_IDCT_SIMPLE;
2084
2085     if (MPV_common_init(s) < 0)
2086         return -1;
2087     exchange_uv(s);//common init reset pblocks, so we swap them here
2088     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2089     s1->mpeg_enc_ctx_allocated = 1;
2090
2091     for(i=0;i<64;i++) {
2092         int j= s->dsp.idct_permutation[i];
2093         v = ff_mpeg1_default_intra_matrix[i];
2094         s->intra_matrix[j] = v;
2095         s->chroma_intra_matrix[j] = v;
2096
2097         v = ff_mpeg1_default_non_intra_matrix[i];
2098         s->inter_matrix[j] = v;
2099         s->chroma_inter_matrix[j] = v;
2100     }
2101
2102     s->progressive_sequence = 1;
2103     s->progressive_frame = 1;
2104     s->picture_structure = PICT_FRAME;
2105     s->frame_pred_frame_dct = 1;
2106     s->chroma_format = 1;
2107     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2108     avctx->sub_id = 2; /* indicates MPEG-2 */
2109     return 0;
2110 }
2111
2112
2113 static void mpeg_decode_user_data(AVCodecContext *avctx,
2114                                   const uint8_t *buf, int buf_size)
2115 {
2116     const uint8_t *p;
2117     int len, flags;
2118     p = buf;
2119     len = buf_size;
2120
2121     /* we parse the DTG active format information */
2122     if (len >= 5 &&
2123         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2124         flags = p[4];
2125         p += 5;
2126         len -= 5;
2127         if (flags & 0x80) {
2128             /* skip event id */
2129             if (len < 2)
2130                 return;
2131             p += 2;
2132             len -= 2;
2133         }
2134         if (flags & 0x40) {
2135             if (len < 1)
2136                 return;
2137             avctx->dtg_active_format = p[0] & 0x0f;
2138         }
2139     }
2140 }
2141
2142 static void mpeg_decode_gop(AVCodecContext *avctx,
2143                             const uint8_t *buf, int buf_size){
2144     Mpeg1Context *s1 = avctx->priv_data;
2145     MpegEncContext *s = &s1->mpeg_enc_ctx;
2146
2147     int drop_frame_flag;
2148     int time_code_hours, time_code_minutes;
2149     int time_code_seconds, time_code_pictures;
2150     int closed_gop, broken_link;
2151
2152     init_get_bits(&s->gb, buf, buf_size*8);
2153
2154     drop_frame_flag = get_bits1(&s->gb);
2155
2156     time_code_hours=get_bits(&s->gb,5);
2157     time_code_minutes = get_bits(&s->gb,6);
2158     skip_bits1(&s->gb);//marker bit
2159     time_code_seconds = get_bits(&s->gb,6);
2160     time_code_pictures = get_bits(&s->gb,6);
2161
2162     closed_gop  = get_bits1(&s->gb);
2163     /*broken_link indicate that after editing the
2164       reference frames of the first B-Frames after GOP I-Frame
2165       are missing (open gop)*/
2166     broken_link = get_bits1(&s->gb);
2167
2168     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2169         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2170             time_code_hours, time_code_minutes, time_code_seconds,
2171             time_code_pictures, closed_gop, broken_link);
2172 }
2173 /**
2174  * Finds the end of the current frame in the bitstream.
2175  * @return the position of the first byte of the next frame, or -1
2176  */
2177 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2178 {
2179     int i;
2180     uint32_t state= pc->state;
2181
2182     /* EOF considered as end of frame */
2183     if (buf_size == 0)
2184         return 0;
2185
2186 /*
2187  0  frame start         -> 1/4
2188  1  first_SEQEXT        -> 0/2
2189  2  first field start   -> 3/0
2190  3  second_SEQEXT       -> 2/0
2191  4  searching end
2192 */
2193
2194     for(i=0; i<buf_size; i++){
2195         assert(pc->frame_start_found>=0 && pc->frame_start_found<=4);
2196         if(pc->frame_start_found&1){
2197             if(state == EXT_START_CODE && (buf[i]&0xF0) != 0x80)
2198                 pc->frame_start_found--;
2199             else if(state == EXT_START_CODE+2){
2200                 if((buf[i]&3) == 3) pc->frame_start_found= 0;
2201                 else                pc->frame_start_found= (pc->frame_start_found+1)&3;
2202             }
2203             state++;
2204         }else{
2205             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2206             if(pc->frame_start_found==0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2207                 i++;
2208                 pc->frame_start_found=4;
2209             }
2210             if(state == SEQ_END_CODE){
2211                 pc->state=-1;
2212                 return i+1;
2213             }
2214             if(pc->frame_start_found==2 && state == SEQ_START_CODE)
2215                 pc->frame_start_found= 0;
2216             if(pc->frame_start_found<4 && state == EXT_START_CODE)
2217                 pc->frame_start_found++;
2218             if(pc->frame_start_found == 4 && (state&0xFFFFFF00) == 0x100){
2219                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2220                     pc->frame_start_found=0;
2221                     pc->state=-1;
2222                     return i-3;
2223                 }
2224             }
2225         }
2226     }
2227     pc->state= state;
2228     return END_NOT_FOUND;
2229 }
2230
2231 static int decode_chunks(AVCodecContext *avctx,
2232                              AVFrame *picture, int *data_size,
2233                              const uint8_t *buf, int buf_size);
2234
2235 /* handle buffering and image synchronisation */
2236 static int mpeg_decode_frame(AVCodecContext *avctx,
2237                              void *data, int *data_size,
2238                              const uint8_t *buf, int buf_size)
2239 {
2240     Mpeg1Context *s = avctx->priv_data;
2241     AVFrame *picture = data;
2242     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2243     dprintf(avctx, "fill_buffer\n");
2244
2245     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2246         /* special case for last picture */
2247         if (s2->low_delay==0 && s2->next_picture_ptr) {
2248             *picture= *(AVFrame*)s2->next_picture_ptr;
2249             s2->next_picture_ptr= NULL;
2250
2251             *data_size = sizeof(AVFrame);
2252         }
2253         return buf_size;
2254     }
2255
2256     if(s2->flags&CODEC_FLAG_TRUNCATED){
2257         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2258
2259         if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2260             return buf_size;
2261     }
2262
2263 #if 0
2264     if (s->repeat_field % 2 == 1) {
2265         s->repeat_field++;
2266         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2267         //        s2->picture_number, s->repeat_field);
2268         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2269             *data_size = sizeof(AVPicture);
2270             goto the_end;
2271         }
2272     }
2273 #endif
2274
2275     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == AV_RL32("VCR2"))
2276         vcr2_init_sequence(avctx);
2277
2278     s->slice_count= 0;
2279
2280     if(avctx->extradata && !avctx->frame_number)
2281         decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
2282
2283     return decode_chunks(avctx, picture, data_size, buf, buf_size);
2284 }
2285
2286 static int decode_chunks(AVCodecContext *avctx,
2287                              AVFrame *picture, int *data_size,
2288                              const uint8_t *buf, int buf_size)
2289 {
2290     Mpeg1Context *s = avctx->priv_data;
2291     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2292     const uint8_t *buf_ptr = buf;
2293     const uint8_t *buf_end = buf + buf_size;
2294     int ret, input_size;
2295
2296     for(;;) {
2297         /* find next start code */
2298         uint32_t start_code = -1;
2299         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2300         if (start_code > 0x1ff){
2301             if(s2->pict_type != FF_B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2302                 if(avctx->thread_count > 1){
2303                     int i;
2304
2305                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count, sizeof(void*));
2306                     for(i=0; i<s->slice_count; i++)
2307                         s2->error_count += s2->thread_context[i]->error_count;
2308                 }
2309
2310                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
2311                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2312
2313                 if (slice_end(avctx, picture)) {
2314                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2315                         *data_size = sizeof(AVPicture);
2316                 }
2317             }
2318             s2->pict_type= 0;
2319             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2320         }
2321
2322         input_size = buf_end - buf_ptr;
2323
2324         if(avctx->debug & FF_DEBUG_STARTCODE){
2325             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2326         }
2327
2328         /* prepare data for next start code */
2329         switch(start_code) {
2330         case SEQ_START_CODE:
2331             mpeg1_decode_sequence(avctx, buf_ptr,
2332                                     input_size);
2333             break;
2334
2335         case PICTURE_START_CODE:
2336             /* we have a complete image: we try to decompress it */
2337             if(mpeg1_decode_picture(avctx,
2338                                     buf_ptr, input_size) < 0)
2339                 s2->pict_type=0;
2340             break;
2341         case EXT_START_CODE:
2342             mpeg_decode_extension(avctx,
2343                                     buf_ptr, input_size);
2344             break;
2345         case USER_START_CODE:
2346             mpeg_decode_user_data(avctx,
2347                                     buf_ptr, input_size);
2348             break;
2349         case GOP_START_CODE:
2350             s2->first_field=0;
2351             mpeg_decode_gop(avctx,
2352                                     buf_ptr, input_size);
2353             break;
2354         default:
2355             if (start_code >= SLICE_MIN_START_CODE &&
2356                 start_code <= SLICE_MAX_START_CODE) {
2357                 int mb_y= start_code - SLICE_MIN_START_CODE;
2358
2359                 if(s2->last_picture_ptr==NULL){
2360                 /* Skip B-frames if we do not have reference frames. */
2361                     if(s2->pict_type==FF_B_TYPE) break;
2362                 }
2363                 if(s2->next_picture_ptr==NULL){
2364                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2365                     if(s2->pict_type==FF_P_TYPE && (s2->first_field || s2->picture_structure==PICT_FRAME)) break;
2366                 }
2367                 /* Skip B-frames if we are in a hurry. */
2368                 if(avctx->hurry_up && s2->pict_type==FF_B_TYPE) break;
2369                 if(  (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==FF_B_TYPE)
2370                     ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=FF_I_TYPE)
2371                     || avctx->skip_frame >= AVDISCARD_ALL)
2372                     break;
2373                 /* Skip everything if we are in a hurry>=5. */
2374                 if(avctx->hurry_up>=5) break;
2375
2376                 if (!s->mpeg_enc_ctx_allocated) break;
2377
2378                 if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
2379                     if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2380                         break;
2381                 }
2382
2383                 if(!s2->pict_type){
2384                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2385                     break;
2386                 }
2387
2388                 if(s2->first_slice){
2389                     s2->first_slice=0;
2390                             if(mpeg_field_start(s2) < 0)
2391                         return -1;
2392                     }
2393                 if(!s2->current_picture_ptr){
2394                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2395                     return -1;
2396                 }
2397
2398                 if (avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU) {
2399                     s->slice_count++;
2400                     break;
2401                 }
2402
2403                 if(avctx->thread_count > 1){
2404                     int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2405                     if(threshold <= mb_y){
2406                         MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2407
2408                         thread_context->start_mb_y= mb_y;
2409                         thread_context->end_mb_y  = s2->mb_height;
2410                         if(s->slice_count){
2411                             s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2412                             ff_update_duplicate_context(thread_context, s2);
2413                         }
2414                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2415                         s->slice_count++;
2416                     }
2417                     buf_ptr += 2; //FIXME add minimum number of bytes per slice
2418                 }else{
2419                     ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2420                     emms_c();
2421
2422                     if(ret < 0){
2423                         if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2424                             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);
2425                     }else{
2426                         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);
2427                     }
2428                 }
2429             }
2430             break;
2431         }
2432     }
2433 }
2434
2435 static int mpeg_decode_end(AVCodecContext *avctx)
2436 {
2437     Mpeg1Context *s = avctx->priv_data;
2438
2439     if (s->mpeg_enc_ctx_allocated)
2440         MPV_common_end(&s->mpeg_enc_ctx);
2441     return 0;
2442 }
2443
2444 AVCodec mpeg1video_decoder = {
2445     "mpeg1video",
2446     CODEC_TYPE_VIDEO,
2447     CODEC_ID_MPEG1VIDEO,
2448     sizeof(Mpeg1Context),
2449     mpeg_decode_init,
2450     NULL,
2451     mpeg_decode_end,
2452     mpeg_decode_frame,
2453     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2454     .flush= ff_mpeg_flush,
2455     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2456 };
2457
2458 AVCodec mpeg2video_decoder = {
2459     "mpeg2video",
2460     CODEC_TYPE_VIDEO,
2461     CODEC_ID_MPEG2VIDEO,
2462     sizeof(Mpeg1Context),
2463     mpeg_decode_init,
2464     NULL,
2465     mpeg_decode_end,
2466     mpeg_decode_frame,
2467     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2468     .flush= ff_mpeg_flush,
2469     .long_name= NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2470 };
2471
2472 //legacy decoder
2473 AVCodec mpegvideo_decoder = {
2474     "mpegvideo",
2475     CODEC_TYPE_VIDEO,
2476     CODEC_ID_MPEG2VIDEO,
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 #if CONFIG_MPEG_XVMC_DECODER
2488 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx){
2489     Mpeg1Context *s;
2490
2491     if( avctx->thread_count > 1)
2492         return -1;
2493     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2494         return -1;
2495     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2496         dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2497     }
2498     mpeg_decode_init(avctx);
2499     s = avctx->priv_data;
2500
2501     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2502     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2503
2504     return 0;
2505 }
2506
2507 AVCodec mpeg_xvmc_decoder = {
2508     "mpegvideo_xvmc",
2509     CODEC_TYPE_VIDEO,
2510     CODEC_ID_MPEG2VIDEO_XVMC,
2511     sizeof(Mpeg1Context),
2512     mpeg_mc_decode_init,
2513     NULL,
2514     mpeg_decode_end,
2515     mpeg_decode_frame,
2516     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2517     .flush= ff_mpeg_flush,
2518     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video XvMC (X-Video Motion Compensation)"),
2519 };
2520
2521 #endif
2522
2523 #if CONFIG_MPEG_VDPAU_DECODER
2524 AVCodec mpeg_vdpau_decoder = {
2525     "mpegvideo_vdpau",
2526     CODEC_TYPE_VIDEO,
2527     CODEC_ID_MPEG2VIDEO,
2528     sizeof(Mpeg1Context),
2529     mpeg_decode_init,
2530     NULL,
2531     mpeg_decode_end,
2532     mpeg_decode_frame,
2533     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2534     .flush= ff_mpeg_flush,
2535     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2536 };
2537 #endif
2538
2539 #if CONFIG_MPEG1_VDPAU_DECODER
2540 AVCodec mpeg1_vdpau_decoder = {
2541     "mpeg1video_vdpau",
2542     CODEC_TYPE_VIDEO,
2543     CODEC_ID_MPEG1VIDEO,
2544     sizeof(Mpeg1Context),
2545     mpeg_decode_init,
2546     NULL,
2547     mpeg_decode_end,
2548     mpeg_decode_frame,
2549     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2550     .flush= ff_mpeg_flush,
2551     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2552 };
2553 #endif
2554