libavcodec/mpeg12.c

   1 /*
   2  * MPEG1/2 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 mpeg12.c
  25  * MPEG1/2 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
  38 //#undef NDEBUG
  39 //#include <assert.h>
  40
  41
  42 #define DC_VLC_BITS 9
  43 #define MV_VLC_BITS 9
  44 #define MBINCR_VLC_BITS 9
  45 #define MB_PAT_VLC_BITS 9
  46 #define MB_PTYPE_VLC_BITS 6
  47 #define MB_BTYPE_VLC_BITS 6
  48 #define TEX_VLC_BITS 9
  49
  50 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
  51                               DCTELEM *block,
  52                               int n);
  53 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
  54                               DCTELEM *block,
  55                               int n);
  56 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
  57 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
  58                                         DCTELEM *block,
  59                                         int n);
  60 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
  61                                     DCTELEM *block,
  62                                     int n);
  63 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
  64 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
  65 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
  66 static void exchange_uv(MpegEncContext *s);
  67
  68 extern int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
  69 extern int XVMC_field_end(MpegEncContext *s);
  70 extern void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
  71 extern void XVMC_init_block(MpegEncContext *s);//set s->block
  72
  73 static const enum PixelFormat pixfmt_yuv_420[]= {PIX_FMT_YUV420P,PIX_FMT_NONE};
  74 static const enum PixelFormat pixfmt_yuv_422[]= {PIX_FMT_YUV422P,PIX_FMT_NONE};
  75 static const enum PixelFormat pixfmt_yuv_444[]= {PIX_FMT_YUV444P,PIX_FMT_NONE};
  76 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
  77                                            PIX_FMT_XVMC_MPEG2_IDCT,
  78                                            PIX_FMT_XVMC_MPEG2_MC,
  79                                            PIX_FMT_NONE};
  80
  81 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
  82
  83
  84 #define INIT_2D_VLC_RL(rl, static_size)\
  85 {\
  86     static RL_VLC_ELEM rl_vlc_table[static_size];\
  87     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
  88              &rl.table_vlc[0][1], 4, 2,\
  89              &rl.table_vlc[0][0], 4, 2, static_size);\
  90 \
  91     rl.rl_vlc[0]= rl_vlc_table;\
  92     init_2d_vlc_rl(&rl);\
  93 }
  94
  95 static void init_2d_vlc_rl(RLTable *rl)
  96 {
  97     int i;
  98
  99     for(i=0; i<rl->vlc.table_size; i++){
 100         int code= rl->vlc.table[i][0];
 101         int len = rl->vlc.table[i][1];
 102         int level, run;
 103
 104         if(len==0){ // illegal code
 105             run= 65;
 106             level= MAX_LEVEL;
 107         }else if(len<0){ //more bits needed
 108             run= 0;
 109             level= code;
 110         }else{
 111             if(code==rl->n){ //esc
 112                 run= 65;
 113                 level= 0;
 114             }else if(code==rl->n+1){ //eob
 115                 run= 0;
 116                 level= 127;
 117             }else{
 118                 run=   rl->table_run  [code] + 1;
 119                 level= rl->table_level[code];
 120             }
 121         }
 122         rl->rl_vlc[0][i].len= len;
 123         rl->rl_vlc[0][i].level= level;
 124         rl->rl_vlc[0][i].run= run;
 125     }
 126 }
 127
 128 void ff_mpeg12_common_init(MpegEncContext *s)
 129 {
 130
 131     s->y_dc_scale_table=
 132     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
 133
 134 }
 135
 136 void ff_mpeg1_clean_buffers(MpegEncContext *s){
 137     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
 138     s->last_dc[1] = s->last_dc[0];
 139     s->last_dc[2] = s->last_dc[0];
 140     memset(s->last_mv, 0, sizeof(s->last_mv));
 141 }
 142
 143
 144 /******************************************/
 145 /* decoding */
 146
 147 static VLC dc_lum_vlc;
 148 static VLC dc_chroma_vlc;
 149 static VLC mv_vlc;
 150 static VLC mbincr_vlc;
 151 static VLC mb_ptype_vlc;
 152 static VLC mb_btype_vlc;
 153 static VLC mb_pat_vlc;
 154
 155 static void init_vlcs(void)
 156 {
 157     static int done = 0;
 158
 159     if (!done) {
 160         done = 1;
 161
 162         INIT_VLC_STATIC(&dc_lum_vlc, DC_VLC_BITS, 12,
 163                  ff_mpeg12_vlc_dc_lum_bits, 1, 1,
 164                  ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
 165         INIT_VLC_STATIC(&dc_chroma_vlc,  DC_VLC_BITS, 12,
 166                  ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
 167                  ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
 168         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
 169                  &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
 170                  &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
 171         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
 172                  &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
 173                  &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
 174         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
 175                  &ff_mpeg12_mbPatTable[0][1], 2, 1,
 176                  &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
 177
 178         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
 179                  &table_mb_ptype[0][1], 2, 1,
 180                  &table_mb_ptype[0][0], 2, 1, 64);
 181         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
 182                  &table_mb_btype[0][1], 2, 1,
 183                  &table_mb_btype[0][0], 2, 1, 64);
 184         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
 185         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
 186
 187         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
 188         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
 189     }
 190 }
 191
 192 static inline int get_dmv(MpegEncContext *s)
 193 {
 194     if(get_bits1(&s->gb))
 195         return 1 - (get_bits1(&s->gb) << 1);
 196     else
 197         return 0;
 198 }
 199
 200 static inline int get_qscale(MpegEncContext *s)
 201 {
 202     int qscale = get_bits(&s->gb, 5);
 203     if (s->q_scale_type) {
 204         return non_linear_qscale[qscale];
 205     } else {
 206         return qscale << 1;
 207     }
 208 }
 209
 210 /* motion type (for mpeg2) */
 211 #define MT_FIELD 1
 212 #define MT_FRAME 2
 213 #define MT_16X8  2
 214 #define MT_DMV   3
 215
 216 static int mpeg_decode_mb(MpegEncContext *s,
 217                           DCTELEM block[12][64])
 218 {
 219     int i, j, k, cbp, val, mb_type, motion_type;
 220     const int mb_block_count = 4 + (1<< s->chroma_format);
 221
 222     dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 223
 224     assert(s->mb_skipped==0);
 225
 226     if (s->mb_skip_run-- != 0) {
 227         if (s->pict_type == FF_P_TYPE) {
 228             s->mb_skipped = 1;
 229             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 230         } else {
 231             int mb_type;
 232
 233             if(s->mb_x)
 234                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
 235             else
 236                 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,
 237             if(IS_INTRA(mb_type))
 238                 return -1;
 239
 240             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
 241                 mb_type | MB_TYPE_SKIP;
 242 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
 243
 244             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
 245                 s->mb_skipped = 1;
 246         }
 247
 248         return 0;
 249     }
 250
 251     switch(s->pict_type) {
 252     default:
 253     case FF_I_TYPE:
 254         if (get_bits1(&s->gb) == 0) {
 255             if (get_bits1(&s->gb) == 0){
 256                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
 257                 return -1;
 258             }
 259             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 260         } else {
 261             mb_type = MB_TYPE_INTRA;
 262         }
 263         break;
 264     case FF_P_TYPE:
 265         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 266         if (mb_type < 0){
 267             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 268             return -1;
 269         }
 270         mb_type = ptype2mb_type[ mb_type ];
 271         break;
 272     case FF_B_TYPE:
 273         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 274         if (mb_type < 0){
 275             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 276             return -1;
 277         }
 278         mb_type = btype2mb_type[ mb_type ];
 279         break;
 280     }
 281     dprintf(s->avctx, "mb_type=%x\n", mb_type);
 282 //    motion_type = 0; /* avoid warning */
 283     if (IS_INTRA(mb_type)) {
 284         s->dsp.clear_blocks(s->block[0]);
 285
 286         if(!s->chroma_y_shift){
 287             s->dsp.clear_blocks(s->block[6]);
 288         }
 289
 290         /* compute dct type */
 291         if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
 292             !s->frame_pred_frame_dct) {
 293             s->interlaced_dct = get_bits1(&s->gb);
 294         }
 295
 296         if (IS_QUANT(mb_type))
 297             s->qscale = get_qscale(s);
 298
 299         if (s->concealment_motion_vectors) {
 300             /* just parse them */
 301             if (s->picture_structure != PICT_FRAME)
 302                 skip_bits1(&s->gb); /* field select */
 303
 304             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 305                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 306             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 307                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 308
 309             skip_bits1(&s->gb); /* marker */
 310         }else
 311             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 312         s->mb_intra = 1;
 313 #ifdef HAVE_XVMC
 314         //one 1 we memcpy blocks in xvmcvideo
 315         if(s->avctx->xvmc_acceleration > 1){
 316             XVMC_pack_pblocks(s,-1);//inter are always full blocks
 317             if(s->swap_uv){
 318                 exchange_uv(s);
 319             }
 320         }
 321 #endif
 322
 323         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 324             if(s->flags2 & CODEC_FLAG2_FAST){
 325                 for(i=0;i<6;i++) {
 326                     mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
 327                 }
 328             }else{
 329                 for(i=0;i<mb_block_count;i++) {
 330                     if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
 331                         return -1;
 332                 }
 333             }
 334         } else {
 335             for(i=0;i<6;i++) {
 336                 if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
 337                     return -1;
 338             }
 339         }
 340     } else {
 341         if (mb_type & MB_TYPE_ZERO_MV){
 342             assert(mb_type & MB_TYPE_CBP);
 343
 344             s->mv_dir = MV_DIR_FORWARD;
 345             if(s->picture_structure == PICT_FRAME){
 346                 if(!s->frame_pred_frame_dct)
 347                     s->interlaced_dct = get_bits1(&s->gb);
 348                 s->mv_type = MV_TYPE_16X16;
 349             }else{
 350                 s->mv_type = MV_TYPE_FIELD;
 351                 mb_type |= MB_TYPE_INTERLACED;
 352                 s->field_select[0][0]= s->picture_structure - 1;
 353             }
 354
 355             if (IS_QUANT(mb_type))
 356                 s->qscale = get_qscale(s);
 357
 358             s->last_mv[0][0][0] = 0;
 359             s->last_mv[0][0][1] = 0;
 360             s->last_mv[0][1][0] = 0;
 361             s->last_mv[0][1][1] = 0;
 362             s->mv[0][0][0] = 0;
 363             s->mv[0][0][1] = 0;
 364         }else{
 365             assert(mb_type & MB_TYPE_L0L1);
 366 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 367             /* get additional motion vector type */
 368             if (s->frame_pred_frame_dct)
 369                 motion_type = MT_FRAME;
 370             else{
 371                 motion_type = get_bits(&s->gb, 2);
 372                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 373                     s->interlaced_dct = get_bits1(&s->gb);
 374             }
 375
 376             if (IS_QUANT(mb_type))
 377                 s->qscale = get_qscale(s);
 378
 379             /* motion vectors */
 380             s->mv_dir= (mb_type>>13)&3;
 381             dprintf(s->avctx, "motion_type=%d\n", motion_type);
 382             switch(motion_type) {
 383             case MT_FRAME: /* or MT_16X8 */
 384                 if (s->picture_structure == PICT_FRAME) {
 385                     mb_type |= MB_TYPE_16x16;
 386                     s->mv_type = MV_TYPE_16X16;
 387                     for(i=0;i<2;i++) {
 388                         if (USES_LIST(mb_type, i)) {
 389                             /* MT_FRAME */
 390                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
 391                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
 392                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
 393                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
 394                             /* full_pel: only for mpeg1 */
 395                             if (s->full_pel[i]){
 396                                 s->mv[i][0][0] <<= 1;
 397                                 s->mv[i][0][1] <<= 1;
 398                             }
 399                         }
 400                     }
 401                 } else {
 402                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 403                     s->mv_type = MV_TYPE_16X8;
 404                     for(i=0;i<2;i++) {
 405                         if (USES_LIST(mb_type, i)) {
 406                             /* MT_16X8 */
 407                             for(j=0;j<2;j++) {
 408                                 s->field_select[i][j] = get_bits1(&s->gb);
 409                                 for(k=0;k<2;k++) {
 410                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 411                                                              s->last_mv[i][j][k]);
 412                                     s->last_mv[i][j][k] = val;
 413                                     s->mv[i][j][k] = val;
 414                                 }
 415                             }
 416                         }
 417                     }
 418                 }
 419                 break;
 420             case MT_FIELD:
 421                 s->mv_type = MV_TYPE_FIELD;
 422                 if (s->picture_structure == PICT_FRAME) {
 423                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 424                     for(i=0;i<2;i++) {
 425                         if (USES_LIST(mb_type, i)) {
 426                             for(j=0;j<2;j++) {
 427                                 s->field_select[i][j] = get_bits1(&s->gb);
 428                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 429                                                          s->last_mv[i][j][0]);
 430                                 s->last_mv[i][j][0] = val;
 431                                 s->mv[i][j][0] = val;
 432                                 dprintf(s->avctx, "fmx=%d\n", val);
 433                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 434                                                          s->last_mv[i][j][1] >> 1);
 435                                 s->last_mv[i][j][1] = val << 1;
 436                                 s->mv[i][j][1] = val;
 437                                 dprintf(s->avctx, "fmy=%d\n", val);
 438                             }
 439                         }
 440                     }
 441                 } else {
 442                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 443                     for(i=0;i<2;i++) {
 444                         if (USES_LIST(mb_type, i)) {
 445                             s->field_select[i][0] = get_bits1(&s->gb);
 446                             for(k=0;k<2;k++) {
 447                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 448                                                          s->last_mv[i][0][k]);
 449                                 s->last_mv[i][0][k] = val;
 450                                 s->last_mv[i][1][k] = val;
 451                                 s->mv[i][0][k] = val;
 452                             }
 453                         }
 454                     }
 455                 }
 456                 break;
 457             case MT_DMV:
 458                 s->mv_type = MV_TYPE_DMV;
 459                 for(i=0;i<2;i++) {
 460                     if (USES_LIST(mb_type, i)) {
 461                         int dmx, dmy, mx, my, m;
 462                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 463                                                 s->last_mv[i][0][0]);
 464                         s->last_mv[i][0][0] = mx;
 465                         s->last_mv[i][1][0] = mx;
 466                         dmx = get_dmv(s);
 467                         my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 468                                                 s->last_mv[i][0][1] >> 1);
 469                         dmy = get_dmv(s);
 470
 471
 472                         s->last_mv[i][0][1] = my<<1;
 473                         s->last_mv[i][1][1] = my<<1;
 474
 475                         s->mv[i][0][0] = mx;
 476                         s->mv[i][0][1] = my;
 477                         s->mv[i][1][0] = mx;//not used
 478                         s->mv[i][1][1] = my;//not used
 479
 480                         if (s->picture_structure == PICT_FRAME) {
 481                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 482
 483                             //m = 1 + 2 * s->top_field_first;
 484                             m = s->top_field_first ? 1 : 3;
 485
 486                             /* top -> top pred */
 487                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 488                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 489                             m = 4 - m;
 490                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 491                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 492                         } else {
 493                             mb_type |= MB_TYPE_16x16;
 494
 495                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 496                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 497                             if(s->picture_structure == PICT_TOP_FIELD)
 498                                 s->mv[i][2][1]--;
 499                             else
 500                                 s->mv[i][2][1]++;
 501                         }
 502                     }
 503                 }
 504                 break;
 505             default:
 506                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 507                 return -1;
 508             }
 509         }
 510
 511         s->mb_intra = 0;
 512         if (HAS_CBP(mb_type)) {
 513             s->dsp.clear_blocks(s->block[0]);
 514
 515             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 516             if(mb_block_count > 6){
 517                  cbp<<= mb_block_count-6;
 518                  cbp |= get_bits(&s->gb, mb_block_count-6);
 519                  s->dsp.clear_blocks(s->block[6]);
 520             }
 521             if (cbp <= 0){
 522                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
 523                 return -1;
 524             }
 525
 526 #ifdef HAVE_XVMC
 527             //on 1 we memcpy blocks in xvmcvideo
 528             if(s->avctx->xvmc_acceleration > 1){
 529                 XVMC_pack_pblocks(s,cbp);
 530                 if(s->swap_uv){
 531                     exchange_uv(s);
 532                 }
 533             }
 534 #endif
 535
 536             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 537                 if(s->flags2 & CODEC_FLAG2_FAST){
 538                     for(i=0;i<6;i++) {
 539                         if(cbp & 32) {
 540                             mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
 541                         } else {
 542                             s->block_last_index[i] = -1;
 543                         }
 544                         cbp+=cbp;
 545                     }
 546                 }else{
 547                     cbp<<= 12-mb_block_count;
 548
 549                     for(i=0;i<mb_block_count;i++) {
 550                         if ( cbp & (1<<11) ) {
 551                             if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
 552                                 return -1;
 553                         } else {
 554                             s->block_last_index[i] = -1;
 555                         }
 556                         cbp+=cbp;
 557                     }
 558                 }
 559             } else {
 560                 if(s->flags2 & CODEC_FLAG2_FAST){
 561                     for(i=0;i<6;i++) {
 562                         if (cbp & 32) {
 563                             mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
 564                         } else {
 565                             s->block_last_index[i] = -1;
 566                         }
 567                         cbp+=cbp;
 568                     }
 569                 }else{
 570                     for(i=0;i<6;i++) {
 571                         if (cbp & 32) {
 572                             if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
 573                                 return -1;
 574                         } else {
 575                             s->block_last_index[i] = -1;
 576                         }
 577                         cbp+=cbp;
 578                     }
 579                 }
 580             }
 581         }else{
 582             for(i=0;i<12;i++)
 583                 s->block_last_index[i] = -1;
 584         }
 585     }
 586
 587     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
 588
 589     return 0;
 590 }
 591
 592 /* as h263, but only 17 codes */
 593 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 594 {
 595     int code, sign, val, l, shift;
 596
 597     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
 598     if (code == 0) {
 599         return pred;
 600     }
 601     if (code < 0) {
 602         return 0xffff;
 603     }
 604
 605     sign = get_bits1(&s->gb);
 606     shift = fcode - 1;
 607     val = code;
 608     if (shift) {
 609         val = (val - 1) << shift;
 610         val |= get_bits(&s->gb, shift);
 611         val++;
 612     }
 613     if (sign)
 614         val = -val;
 615     val += pred;
 616
 617     /* modulo decoding */
 618     l= INT_BIT - 5 - shift;
 619     val = (val<<l)>>l;
 620     return val;
 621 }
 622
 623 static inline int decode_dc(GetBitContext *gb, int component)
 624 {
 625     int code, diff;
 626
 627     if (component == 0) {
 628         code = get_vlc2(gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
 629     } else {
 630         code = get_vlc2(gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
 631     }
 632     if (code < 0){
 633         av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
 634         return 0xffff;
 635     }
 636     if (code == 0) {
 637         diff = 0;
 638     } else {
 639         diff = get_xbits(gb, code);
 640     }
 641     return diff;
 642 }
 643
 644 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
 645                                DCTELEM *block,
 646                                int n)
 647 {
 648     int level, dc, diff, i, j, run;
 649     int component;
 650     RLTable *rl = &ff_rl_mpeg1;
 651     uint8_t * const scantable= s->intra_scantable.permutated;
 652     const uint16_t *quant_matrix= s->intra_matrix;
 653     const int qscale= s->qscale;
 654
 655     /* DC coef */
 656     component = (n <= 3 ? 0 : n - 4 + 1);
 657     diff = decode_dc(&s->gb, component);
 658     if (diff >= 0xffff)
 659         return -1;
 660     dc = s->last_dc[component];
 661     dc += diff;
 662     s->last_dc[component] = dc;
 663     block[0] = dc<<3;
 664     dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
 665     i = 0;
 666     {
 667         OPEN_READER(re, &s->gb);
 668         /* now quantify & encode AC coefs */
 669         for(;;) {
 670             UPDATE_CACHE(re, &s->gb);
 671             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 672
 673             if(level == 127){
 674                 break;
 675             } else if(level != 0) {
 676                 i += run;
 677                 j = scantable[i];
 678                 level= (level*qscale*quant_matrix[j])>>4;
 679                 level= (level-1)|1;
 680                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 681                 LAST_SKIP_BITS(re, &s->gb, 1);
 682             } else {
 683                 /* escape */
 684                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 685                 UPDATE_CACHE(re, &s->gb);
 686                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 687                 if (level == -128) {
 688                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
 689                 } else if (level == 0) {
 690                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
 691                 }
 692                 i += run;
 693                 j = scantable[i];
 694                 if(level<0){
 695                     level= -level;
 696                     level= (level*qscale*quant_matrix[j])>>4;
 697                     level= (level-1)|1;
 698                     level= -level;
 699                 }else{
 700                     level= (level*qscale*quant_matrix[j])>>4;
 701                     level= (level-1)|1;
 702                 }
 703             }
 704             if (i > 63){
 705                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 706                 return -1;
 707             }
 708
 709             block[j] = level;
 710         }
 711         CLOSE_READER(re, &s->gb);
 712     }
 713     s->block_last_index[n] = i;
 714    return 0;
 715 }
 716
 717 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 718                                DCTELEM *block,
 719                                int n)
 720 {
 721     int level, i, j, run;
 722     RLTable *rl = &ff_rl_mpeg1;
 723     uint8_t * const scantable= s->intra_scantable.permutated;
 724     const uint16_t *quant_matrix= s->inter_matrix;
 725     const int qscale= s->qscale;
 726
 727     {
 728         OPEN_READER(re, &s->gb);
 729         i = -1;
 730         /* special case for the first coef. no need to add a second vlc table */
 731         UPDATE_CACHE(re, &s->gb);
 732         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 733             level= (3*qscale*quant_matrix[0])>>5;
 734             level= (level-1)|1;
 735             if(GET_CACHE(re, &s->gb)&0x40000000)
 736                 level= -level;
 737             block[0] = level;
 738             i++;
 739             SKIP_BITS(re, &s->gb, 2);
 740             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 741                 goto end;
 742         }
 743 #if MIN_CACHE_BITS < 19
 744         UPDATE_CACHE(re, &s->gb);
 745 #endif
 746         /* now quantify & encode AC coefs */
 747         for(;;) {
 748             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 749
 750             if(level != 0) {
 751                 i += run;
 752                 j = scantable[i];
 753                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 754                 level= (level-1)|1;
 755                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 756                 SKIP_BITS(re, &s->gb, 1);
 757             } else {
 758                 /* escape */
 759                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 760                 UPDATE_CACHE(re, &s->gb);
 761                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 762                 if (level == -128) {
 763                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 764                 } else if (level == 0) {
 765                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 766                 }
 767                 i += run;
 768                 j = scantable[i];
 769                 if(level<0){
 770                     level= -level;
 771                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 772                     level= (level-1)|1;
 773                     level= -level;
 774                 }else{
 775                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 776                     level= (level-1)|1;
 777                 }
 778             }
 779             if (i > 63){
 780                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 781                 return -1;
 782             }
 783
 784             block[j] = level;
 785 #if MIN_CACHE_BITS < 19
 786             UPDATE_CACHE(re, &s->gb);
 787 #endif
 788             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 789                 break;
 790 #if MIN_CACHE_BITS >= 19
 791             UPDATE_CACHE(re, &s->gb);
 792 #endif
 793         }
 794 end:
 795         LAST_SKIP_BITS(re, &s->gb, 2);
 796         CLOSE_READER(re, &s->gb);
 797     }
 798     s->block_last_index[n] = i;
 799     return 0;
 800 }
 801
 802 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
 803 {
 804     int level, i, j, run;
 805     RLTable *rl = &ff_rl_mpeg1;
 806     uint8_t * const scantable= s->intra_scantable.permutated;
 807     const int qscale= s->qscale;
 808
 809     {
 810         OPEN_READER(re, &s->gb);
 811         i = -1;
 812         /* special case for the first coef. no need to add a second vlc table */
 813         UPDATE_CACHE(re, &s->gb);
 814         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 815             level= (3*qscale)>>1;
 816             level= (level-1)|1;
 817             if(GET_CACHE(re, &s->gb)&0x40000000)
 818                 level= -level;
 819             block[0] = level;
 820             i++;
 821             SKIP_BITS(re, &s->gb, 2);
 822             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 823                 goto end;
 824         }
 825 #if MIN_CACHE_BITS < 19
 826         UPDATE_CACHE(re, &s->gb);
 827 #endif
 828
 829         /* now quantify & encode AC coefs */
 830         for(;;) {
 831             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 832
 833             if(level != 0) {
 834                 i += run;
 835                 j = scantable[i];
 836                 level= ((level*2+1)*qscale)>>1;
 837                 level= (level-1)|1;
 838                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 839                 SKIP_BITS(re, &s->gb, 1);
 840             } else {
 841                 /* escape */
 842                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 843                 UPDATE_CACHE(re, &s->gb);
 844                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 845                 if (level == -128) {
 846                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 847                 } else if (level == 0) {
 848                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 849                 }
 850                 i += run;
 851                 j = scantable[i];
 852                 if(level<0){
 853                     level= -level;
 854                     level= ((level*2+1)*qscale)>>1;
 855                     level= (level-1)|1;
 856                     level= -level;
 857                 }else{
 858                     level= ((level*2+1)*qscale)>>1;
 859                     level= (level-1)|1;
 860                 }
 861             }
 862
 863             block[j] = level;
 864 #if MIN_CACHE_BITS < 19
 865             UPDATE_CACHE(re, &s->gb);
 866 #endif
 867             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 868                 break;
 869 #if MIN_CACHE_BITS >= 19
 870             UPDATE_CACHE(re, &s->gb);
 871 #endif
 872         }
 873 end:
 874         LAST_SKIP_BITS(re, &s->gb, 2);
 875         CLOSE_READER(re, &s->gb);
 876     }
 877     s->block_last_index[n] = i;
 878     return 0;
 879 }
 880
 881
 882 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 883                                DCTELEM *block,
 884                                int n)
 885 {
 886     int level, i, j, run;
 887     RLTable *rl = &ff_rl_mpeg1;
 888     uint8_t * const scantable= s->intra_scantable.permutated;
 889     const uint16_t *quant_matrix;
 890     const int qscale= s->qscale;
 891     int mismatch;
 892
 893     mismatch = 1;
 894
 895     {
 896         OPEN_READER(re, &s->gb);
 897         i = -1;
 898         if (n < 4)
 899             quant_matrix = s->inter_matrix;
 900         else
 901             quant_matrix = s->chroma_inter_matrix;
 902
 903         /* special case for the first coef. no need to add a second vlc table */
 904         UPDATE_CACHE(re, &s->gb);
 905         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 906             level= (3*qscale*quant_matrix[0])>>5;
 907             if(GET_CACHE(re, &s->gb)&0x40000000)
 908                 level= -level;
 909             block[0] = level;
 910             mismatch ^= level;
 911             i++;
 912             SKIP_BITS(re, &s->gb, 2);
 913             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 914                 goto end;
 915         }
 916 #if MIN_CACHE_BITS < 19
 917         UPDATE_CACHE(re, &s->gb);
 918 #endif
 919
 920         /* now quantify & encode AC coefs */
 921         for(;;) {
 922             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 923
 924             if(level != 0) {
 925                 i += run;
 926                 j = scantable[i];
 927                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 928                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 929                 SKIP_BITS(re, &s->gb, 1);
 930             } else {
 931                 /* escape */
 932                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 933                 UPDATE_CACHE(re, &s->gb);
 934                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 935
 936                 i += run;
 937                 j = scantable[i];
 938                 if(level<0){
 939                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
 940                     level= -level;
 941                 }else{
 942                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 943                 }
 944             }
 945             if (i > 63){
 946                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 947                 return -1;
 948             }
 949
 950             mismatch ^= level;
 951             block[j] = level;
 952 #if MIN_CACHE_BITS < 19
 953             UPDATE_CACHE(re, &s->gb);
 954 #endif
 955             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 956                 break;
 957 #if MIN_CACHE_BITS >= 19
 958             UPDATE_CACHE(re, &s->gb);
 959 #endif
 960         }
 961 end:
 962         LAST_SKIP_BITS(re, &s->gb, 2);
 963         CLOSE_READER(re, &s->gb);
 964     }
 965     block[63] ^= (mismatch & 1);
 966
 967     s->block_last_index[n] = i;
 968     return 0;
 969 }
 970
 971 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 972                                DCTELEM *block,
 973                                int n)
 974 {
 975     int level, i, j, run;
 976     RLTable *rl = &ff_rl_mpeg1;
 977     uint8_t * const scantable= s->intra_scantable.permutated;
 978     const int qscale= s->qscale;
 979     OPEN_READER(re, &s->gb);
 980     i = -1;
 981
 982     /* special case for the first coef. no need to add a second vlc table */
 983     UPDATE_CACHE(re, &s->gb);
 984     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 985         level= (3*qscale)>>1;
 986         if(GET_CACHE(re, &s->gb)&0x40000000)
 987             level= -level;
 988         block[0] = level;
 989         i++;
 990         SKIP_BITS(re, &s->gb, 2);
 991         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 992             goto end;
 993     }
 994 #if MIN_CACHE_BITS < 19
 995     UPDATE_CACHE(re, &s->gb);
 996 #endif
 997
 998     /* now quantify & encode AC coefs */
 999     for(;;) {
1000         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1001
1002         if(level != 0) {
1003             i += run;
1004             j = scantable[i];
1005             level= ((level*2+1)*qscale)>>1;
1006             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1007             SKIP_BITS(re, &s->gb, 1);
1008         } else {
1009             /* escape */
1010             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1011             UPDATE_CACHE(re, &s->gb);
1012             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1013
1014             i += run;
1015             j = scantable[i];
1016             if(level<0){
1017                 level= ((-level*2+1)*qscale)>>1;
1018                 level= -level;
1019             }else{
1020                 level= ((level*2+1)*qscale)>>1;
1021             }
1022         }
1023
1024         block[j] = level;
1025 #if MIN_CACHE_BITS < 19
1026         UPDATE_CACHE(re, &s->gb);
1027 #endif
1028         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1029             break;
1030 #if MIN_CACHE_BITS >=19
1031         UPDATE_CACHE(re, &s->gb);
1032 #endif
1033     }
1034 end:
1035     LAST_SKIP_BITS(re, &s->gb, 2);
1036     CLOSE_READER(re, &s->gb);
1037     s->block_last_index[n] = i;
1038     return 0;
1039 }
1040
1041
1042 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1043                                DCTELEM *block,
1044                                int n)
1045 {
1046     int level, dc, diff, i, j, run;
1047     int component;
1048     RLTable *rl;
1049     uint8_t * const scantable= s->intra_scantable.permutated;
1050     const uint16_t *quant_matrix;
1051     const int qscale= s->qscale;
1052     int mismatch;
1053
1054     /* DC coef */
1055     if (n < 4){
1056         quant_matrix = s->intra_matrix;
1057         component = 0;
1058     }else{
1059         quant_matrix = s->chroma_intra_matrix;
1060         component = (n&1) + 1;
1061     }
1062     diff = decode_dc(&s->gb, component);
1063     if (diff >= 0xffff)
1064         return -1;
1065     dc = s->last_dc[component];
1066     dc += diff;
1067     s->last_dc[component] = dc;
1068     block[0] = dc << (3 - s->intra_dc_precision);
1069     dprintf(s->avctx, "dc=%d\n", block[0]);
1070     mismatch = block[0] ^ 1;
1071     i = 0;
1072     if (s->intra_vlc_format)
1073         rl = &ff_rl_mpeg2;
1074     else
1075         rl = &ff_rl_mpeg1;
1076
1077     {
1078         OPEN_READER(re, &s->gb);
1079         /* now quantify & encode AC coefs */
1080         for(;;) {
1081             UPDATE_CACHE(re, &s->gb);
1082             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1083
1084             if(level == 127){
1085                 break;
1086             } else if(level != 0) {
1087                 i += run;
1088                 j = scantable[i];
1089                 level= (level*qscale*quant_matrix[j])>>4;
1090                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1091                 LAST_SKIP_BITS(re, &s->gb, 1);
1092             } else {
1093                 /* escape */
1094                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1095                 UPDATE_CACHE(re, &s->gb);
1096                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1097                 i += run;
1098                 j = scantable[i];
1099                 if(level<0){
1100                     level= (-level*qscale*quant_matrix[j])>>4;
1101                     level= -level;
1102                 }else{
1103                     level= (level*qscale*quant_matrix[j])>>4;
1104                 }
1105             }
1106             if (i > 63){
1107                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1108                 return -1;
1109             }
1110
1111             mismatch^= level;
1112             block[j] = level;
1113         }
1114         CLOSE_READER(re, &s->gb);
1115     }
1116     block[63]^= mismatch&1;
1117
1118     s->block_last_index[n] = i;
1119     return 0;
1120 }
1121
1122 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1123                                DCTELEM *block,
1124                                int n)
1125 {
1126     int level, dc, diff, j, run;
1127     int component;
1128     RLTable *rl;
1129     uint8_t * scantable= s->intra_scantable.permutated;
1130     const uint16_t *quant_matrix;
1131     const int qscale= s->qscale;
1132
1133     /* DC coef */
1134     if (n < 4){
1135         quant_matrix = s->intra_matrix;
1136         component = 0;
1137     }else{
1138         quant_matrix = s->chroma_intra_matrix;
1139         component = (n&1) + 1;
1140     }
1141     diff = decode_dc(&s->gb, component);
1142     if (diff >= 0xffff)
1143         return -1;
1144     dc = s->last_dc[component];
1145     dc += diff;
1146     s->last_dc[component] = dc;
1147     block[0] = dc << (3 - s->intra_dc_precision);
1148     if (s->intra_vlc_format)
1149         rl = &ff_rl_mpeg2;
1150     else
1151         rl = &ff_rl_mpeg1;
1152
1153     {
1154         OPEN_READER(re, &s->gb);
1155         /* now quantify & encode AC coefs */
1156         for(;;) {
1157             UPDATE_CACHE(re, &s->gb);
1158             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1159
1160             if(level == 127){
1161                 break;
1162             } else if(level != 0) {
1163                 scantable += run;
1164                 j = *scantable;
1165                 level= (level*qscale*quant_matrix[j])>>4;
1166                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1167                 LAST_SKIP_BITS(re, &s->gb, 1);
1168             } else {
1169                 /* escape */
1170                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1171                 UPDATE_CACHE(re, &s->gb);
1172                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1173                 scantable += run;
1174                 j = *scantable;
1175                 if(level<0){
1176                     level= (-level*qscale*quant_matrix[j])>>4;
1177                     level= -level;
1178                 }else{
1179                     level= (level*qscale*quant_matrix[j])>>4;
1180                 }
1181             }
1182
1183             block[j] = level;
1184         }
1185         CLOSE_READER(re, &s->gb);
1186     }
1187
1188     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1189     return 0;
1190 }
1191
1192 typedef struct Mpeg1Context {
1193     MpegEncContext mpeg_enc_ctx;
1194     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1195     int repeat_field; /* true if we must repeat the field */
1196     AVPanScan pan_scan; /** some temporary storage for the panscan */
1197     int slice_count;
1198     int swap_uv;//indicate VCR2
1199     int save_aspect_info;
1200     int save_width, save_height;
1201     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1202
1203 } Mpeg1Context;
1204
1205 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1206 {
1207     Mpeg1Context *s = avctx->priv_data;
1208     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1209     int i;
1210
1211     //we need some parmutation to store
1212     //matrixes, until MPV_common_init()
1213     //set the real permutatuon
1214     for(i=0;i<64;i++)
1215        s2->dsp.idct_permutation[i]=i;
1216
1217     MPV_decode_defaults(s2);
1218
1219     s->mpeg_enc_ctx.avctx= avctx;
1220     s->mpeg_enc_ctx.flags= avctx->flags;
1221     s->mpeg_enc_ctx.flags2= avctx->flags2;
1222     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1223     init_vlcs();
1224
1225     s->mpeg_enc_ctx_allocated = 0;
1226     s->mpeg_enc_ctx.picture_number = 0;
1227     s->repeat_field = 0;
1228     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1229     return 0;
1230 }
1231
1232 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1233                                      const uint8_t *new_perm){
1234     uint16_t temp_matrix[64];
1235     int i;
1236
1237     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1238
1239     for(i=0;i<64;i++){
1240         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1241     }
1242 }
1243
1244 //Call this function when we know all parameters
1245 //it may be called in different places for mpeg1 and mpeg2
1246 static int mpeg_decode_postinit(AVCodecContext *avctx){
1247     Mpeg1Context *s1 = avctx->priv_data;
1248     MpegEncContext *s = &s1->mpeg_enc_ctx;
1249     uint8_t old_permutation[64];
1250
1251     if (
1252         (s1->mpeg_enc_ctx_allocated == 0)||
1253         avctx->coded_width  != s->width ||
1254         avctx->coded_height != s->height||
1255         s1->save_width != s->width ||
1256         s1->save_height != s->height ||
1257         s1->save_aspect_info != s->aspect_ratio_info||
1258         0)
1259     {
1260
1261         if (s1->mpeg_enc_ctx_allocated) {
1262             ParseContext pc= s->parse_context;
1263             s->parse_context.buffer=0;
1264             MPV_common_end(s);
1265             s->parse_context= pc;
1266         }
1267
1268         if( (s->width == 0 )||(s->height == 0))
1269             return -2;
1270
1271         avcodec_set_dimensions(avctx, s->width, s->height);
1272         avctx->bit_rate = s->bit_rate;
1273         s1->save_aspect_info = s->aspect_ratio_info;
1274         s1->save_width = s->width;
1275         s1->save_height = s->height;
1276
1277      //low_delay may be forced, in this case we will have B frames
1278      //that behave like P frames
1279         avctx->has_b_frames = !(s->low_delay);
1280
1281         if(avctx->sub_id==1){//s->codec_id==avctx->codec_id==CODEC_ID
1282             //mpeg1 fps
1283             avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1284             avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1285             //mpeg1 aspect
1286             avctx->sample_aspect_ratio= av_d2q(
1287                     1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1288
1289         }else{//mpeg2
1290         //mpeg2 fps
1291             av_reduce(
1292                 &s->avctx->time_base.den,
1293                 &s->avctx->time_base.num,
1294                 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1295                 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1296                 1<<30);
1297         //mpeg2 aspect
1298             if(s->aspect_ratio_info > 1){
1299                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) ){
1300                     s->avctx->sample_aspect_ratio=
1301                         av_div_q(
1302                          ff_mpeg2_aspect[s->aspect_ratio_info],
1303                          (AVRational){s->width, s->height}
1304                          );
1305                 }else{
1306                     s->avctx->sample_aspect_ratio=
1307                         av_div_q(
1308                          ff_mpeg2_aspect[s->aspect_ratio_info],
1309                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
1310                         );
1311                 }
1312             }else{
1313                 s->avctx->sample_aspect_ratio=
1314                     ff_mpeg2_aspect[s->aspect_ratio_info];
1315             }
1316         }//mpeg2
1317
1318         if(avctx->xvmc_acceleration){
1319             avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1320         }else{
1321             if(s->chroma_format <  2){
1322                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
1323             }else
1324             if(s->chroma_format == 2){
1325                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_422);
1326             }else
1327             if(s->chroma_format >  2){
1328                 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_444);
1329             }
1330         }
1331         //until then pix_fmt may be changed right after codec init
1332         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
1333             if( avctx->idct_algo == FF_IDCT_AUTO )
1334                 avctx->idct_algo = FF_IDCT_SIMPLE;
1335
1336         //quantization matrixes may need reordering
1337         //if dct permutation is changed
1338         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1339
1340         if (MPV_common_init(s) < 0)
1341             return -2;
1342
1343         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
1344         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
1345         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1346         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1347
1348         s1->mpeg_enc_ctx_allocated = 1;
1349     }
1350     return 0;
1351 }
1352
1353 static int mpeg1_decode_picture(AVCodecContext *avctx,
1354                                 const uint8_t *buf, int buf_size)
1355 {
1356     Mpeg1Context *s1 = avctx->priv_data;
1357     MpegEncContext *s = &s1->mpeg_enc_ctx;
1358     int ref, f_code, vbv_delay;
1359
1360     if(mpeg_decode_postinit(s->avctx) < 0)
1361        return -2;
1362
1363     init_get_bits(&s->gb, buf, buf_size*8);
1364
1365     ref = get_bits(&s->gb, 10); /* temporal ref */
1366     s->pict_type = get_bits(&s->gb, 3);
1367     if(s->pict_type == 0 || s->pict_type > 3)
1368         return -1;
1369
1370     vbv_delay= get_bits(&s->gb, 16);
1371     if (s->pict_type == FF_P_TYPE || s->pict_type == FF_B_TYPE) {
1372         s->full_pel[0] = get_bits1(&s->gb);
1373         f_code = get_bits(&s->gb, 3);
1374         if (f_code == 0 && avctx->error_resilience >= FF_ER_COMPLIANT)
1375             return -1;
1376         s->mpeg_f_code[0][0] = f_code;
1377         s->mpeg_f_code[0][1] = f_code;
1378     }
1379     if (s->pict_type == FF_B_TYPE) {
1380         s->full_pel[1] = get_bits1(&s->gb);
1381         f_code = get_bits(&s->gb, 3);
1382         if (f_code == 0 && avctx->error_resilience >= FF_ER_COMPLIANT)
1383             return -1;
1384         s->mpeg_f_code[1][0] = f_code;
1385         s->mpeg_f_code[1][1] = f_code;
1386     }
1387     s->current_picture.pict_type= s->pict_type;
1388     s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1389
1390     if(avctx->debug & FF_DEBUG_PICT_INFO)
1391         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1392
1393     s->y_dc_scale = 8;
1394     s->c_dc_scale = 8;
1395     s->first_slice = 1;
1396     return 0;
1397 }
1398
1399 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1400 {
1401     MpegEncContext *s= &s1->mpeg_enc_ctx;
1402     int horiz_size_ext, vert_size_ext;
1403     int bit_rate_ext;
1404
1405     skip_bits(&s->gb, 1); /* profil and level esc*/
1406     s->avctx->profile= get_bits(&s->gb, 3);
1407     s->avctx->level= get_bits(&s->gb, 4);
1408     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1409     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1410     horiz_size_ext = get_bits(&s->gb, 2);
1411     vert_size_ext = get_bits(&s->gb, 2);
1412     s->width |= (horiz_size_ext << 12);
1413     s->height |= (vert_size_ext << 12);
1414     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1415     s->bit_rate += (bit_rate_ext << 18) * 400;
1416     skip_bits1(&s->gb); /* marker */
1417     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1418
1419     s->low_delay = get_bits1(&s->gb);
1420     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1421
1422     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1423     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1424
1425     dprintf(s->avctx, "sequence extension\n");
1426     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1427     s->avctx->sub_id = 2; /* indicates mpeg2 found */
1428
1429     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1430         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1431                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1432
1433 }
1434
1435 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1436 {
1437     MpegEncContext *s= &s1->mpeg_enc_ctx;
1438     int color_description, w, h;
1439
1440     skip_bits(&s->gb, 3); /* video format */
1441     color_description= get_bits1(&s->gb);
1442     if(color_description){
1443         skip_bits(&s->gb, 8); /* color primaries */
1444         skip_bits(&s->gb, 8); /* transfer_characteristics */
1445         skip_bits(&s->gb, 8); /* matrix_coefficients */
1446     }
1447     w= get_bits(&s->gb, 14);
1448     skip_bits(&s->gb, 1); //marker
1449     h= get_bits(&s->gb, 14);
1450     skip_bits(&s->gb, 1); //marker
1451
1452     s1->pan_scan.width= 16*w;
1453     s1->pan_scan.height=16*h;
1454
1455     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1456         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1457 }
1458
1459 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1460 {
1461     MpegEncContext *s= &s1->mpeg_enc_ctx;
1462     int i,nofco;
1463
1464     nofco = 1;
1465     if(s->progressive_sequence){
1466         if(s->repeat_first_field){
1467             nofco++;
1468             if(s->top_field_first)
1469                 nofco++;
1470         }
1471     }else{
1472         if(s->picture_structure == PICT_FRAME){
1473             nofco++;
1474             if(s->repeat_first_field)
1475                 nofco++;
1476         }
1477     }
1478     for(i=0; i<nofco; i++){
1479         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1480         skip_bits(&s->gb, 1); //marker
1481         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1482         skip_bits(&s->gb, 1); //marker
1483     }
1484
1485     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1486         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1487             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1488             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1489             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1490         );
1491 }
1492
1493 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1494 {
1495     int i, v, j;
1496
1497     dprintf(s->avctx, "matrix extension\n");
1498
1499     if (get_bits1(&s->gb)) {
1500         for(i=0;i<64;i++) {
1501             v = get_bits(&s->gb, 8);
1502             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1503             s->intra_matrix[j] = v;
1504             s->chroma_intra_matrix[j] = v;
1505         }
1506     }
1507     if (get_bits1(&s->gb)) {
1508         for(i=0;i<64;i++) {
1509             v = get_bits(&s->gb, 8);
1510             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1511             s->inter_matrix[j] = v;
1512             s->chroma_inter_matrix[j] = v;
1513         }
1514     }
1515     if (get_bits1(&s->gb)) {
1516         for(i=0;i<64;i++) {
1517             v = get_bits(&s->gb, 8);
1518             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1519             s->chroma_intra_matrix[j] = v;
1520         }
1521     }
1522     if (get_bits1(&s->gb)) {
1523         for(i=0;i<64;i++) {
1524             v = get_bits(&s->gb, 8);
1525             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1526             s->chroma_inter_matrix[j] = v;
1527         }
1528     }
1529 }
1530
1531 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1532 {
1533     s->full_pel[0] = s->full_pel[1] = 0;
1534     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1535     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1536     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1537     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1538     s->intra_dc_precision = get_bits(&s->gb, 2);
1539     s->picture_structure = get_bits(&s->gb, 2);
1540     s->top_field_first = get_bits1(&s->gb);
1541     s->frame_pred_frame_dct = get_bits1(&s->gb);
1542     s->concealment_motion_vectors = get_bits1(&s->gb);
1543     s->q_scale_type = get_bits1(&s->gb);
1544     s->intra_vlc_format = get_bits1(&s->gb);
1545     s->alternate_scan = get_bits1(&s->gb);
1546     s->repeat_first_field = get_bits1(&s->gb);
1547     s->chroma_420_type = get_bits1(&s->gb);
1548     s->progressive_frame = get_bits1(&s->gb);
1549
1550     if(s->picture_structure == PICT_FRAME){
1551         s->first_field=0;
1552         s->v_edge_pos= 16*s->mb_height;
1553     }else{
1554         s->first_field ^= 1;
1555         s->v_edge_pos=  8*s->mb_height;
1556         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1557     }
1558
1559     if(s->alternate_scan){
1560         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1561         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1562     }else{
1563         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1564         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1565     }
1566
1567     /* composite display not parsed */
1568     dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1569     dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1570     dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1571     dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1572     dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1573     dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1574     dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1575     dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1576     dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1577 }
1578
1579 static void mpeg_decode_extension(AVCodecContext *avctx,
1580                                   const uint8_t *buf, int buf_size)
1581 {
1582     Mpeg1Context *s1 = avctx->priv_data;
1583     MpegEncContext *s = &s1->mpeg_enc_ctx;
1584     int ext_type;
1585
1586     init_get_bits(&s->gb, buf, buf_size*8);
1587
1588     ext_type = get_bits(&s->gb, 4);
1589     switch(ext_type) {
1590     case 0x1:
1591         mpeg_decode_sequence_extension(s1);
1592         break;
1593     case 0x2:
1594         mpeg_decode_sequence_display_extension(s1);
1595         break;
1596     case 0x3:
1597         mpeg_decode_quant_matrix_extension(s);
1598         break;
1599     case 0x7:
1600         mpeg_decode_picture_display_extension(s1);
1601         break;
1602     case 0x8:
1603         mpeg_decode_picture_coding_extension(s);
1604         break;
1605     }
1606 }
1607
1608 static void exchange_uv(MpegEncContext *s){
1609     short * tmp = s->pblocks[4];
1610     s->pblocks[4] = s->pblocks[5];
1611     s->pblocks[5] = tmp;
1612 }
1613
1614 static int mpeg_field_start(MpegEncContext *s){
1615     AVCodecContext *avctx= s->avctx;
1616     Mpeg1Context *s1 = (Mpeg1Context*)s;
1617
1618     /* start frame decoding */
1619     if(s->first_field || s->picture_structure==PICT_FRAME){
1620         if(MPV_frame_start(s, avctx) < 0)
1621             return -1;
1622
1623         ff_er_frame_start(s);
1624
1625         /* first check if we must repeat the frame */
1626         s->current_picture_ptr->repeat_pict = 0;
1627         if (s->repeat_first_field) {
1628             if (s->progressive_sequence) {
1629                 if (s->top_field_first)
1630                     s->current_picture_ptr->repeat_pict = 4;
1631                 else
1632                     s->current_picture_ptr->repeat_pict = 2;
1633             } else if (s->progressive_frame) {
1634                 s->current_picture_ptr->repeat_pict = 1;
1635             }
1636         }
1637
1638         *s->current_picture_ptr->pan_scan= s1->pan_scan;
1639     }else{ //second field
1640             int i;
1641
1642             if(!s->current_picture_ptr){
1643                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1644                 return -1;
1645             }
1646
1647             for(i=0; i<4; i++){
1648                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1649                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1650                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1651                 }
1652             }
1653     }
1654 #ifdef HAVE_XVMC
1655 // MPV_frame_start will call this function too,
1656 // but we need to call it on every field
1657     if(s->avctx->xvmc_acceleration)
1658          XVMC_field_start(s,avctx);
1659 #endif
1660
1661     return 0;
1662 }
1663
1664 #define DECODE_SLICE_ERROR -1
1665 #define DECODE_SLICE_OK 0
1666
1667 /**
1668  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1669  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1670  *         DECODE_SLICE_OK if this slice is ok<br>
1671  */
1672 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1673                              const uint8_t **buf, int buf_size)
1674 {
1675     MpegEncContext *s = &s1->mpeg_enc_ctx;
1676     AVCodecContext *avctx= s->avctx;
1677     const int field_pic= s->picture_structure != PICT_FRAME;
1678     const int lowres= s->avctx->lowres;
1679
1680     s->resync_mb_x=
1681     s->resync_mb_y= -1;
1682
1683     if (mb_y<<field_pic >= s->mb_height){
1684         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
1685         return -1;
1686     }
1687
1688     init_get_bits(&s->gb, *buf, buf_size*8);
1689
1690     ff_mpeg1_clean_buffers(s);
1691     s->interlaced_dct = 0;
1692
1693     s->qscale = get_qscale(s);
1694
1695     if(s->qscale == 0){
1696         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1697         return -1;
1698     }
1699
1700     /* extra slice info */
1701     while (get_bits1(&s->gb) != 0) {
1702         skip_bits(&s->gb, 8);
1703     }
1704
1705     s->mb_x=0;
1706
1707     for(;;) {
1708         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1709         if (code < 0){
1710             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1711             return -1;
1712         }
1713         if (code >= 33) {
1714             if (code == 33) {
1715                 s->mb_x += 33;
1716             }
1717             /* otherwise, stuffing, nothing to do */
1718         } else {
1719             s->mb_x += code;
1720             break;
1721         }
1722     }
1723     if(s->mb_x >= (unsigned)s->mb_width){
1724         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1725         return -1;
1726     }
1727
1728     s->resync_mb_x= s->mb_x;
1729     s->resync_mb_y= s->mb_y= mb_y;
1730     s->mb_skip_run= 0;
1731     ff_init_block_index(s);
1732
1733     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1734         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1735              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",
1736                  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],
1737                  s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
1738                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1739                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1740                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1741         }
1742     }
1743
1744     for(;;) {
1745 #ifdef HAVE_XVMC
1746         //one 1 we memcpy blocks in xvmcvideo
1747         if(s->avctx->xvmc_acceleration > 1)
1748             XVMC_init_block(s);//set s->block
1749 #endif
1750
1751         if(mpeg_decode_mb(s, s->block) < 0)
1752             return -1;
1753
1754         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1755             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
1756             int xy = s->mb_x*2 + s->mb_y*2*wrap;
1757             int motion_x, motion_y, dir, i;
1758             if(field_pic && !s->first_field)
1759                 xy += wrap/2;
1760
1761             for(i=0; i<2; i++){
1762                 for(dir=0; dir<2; dir++){
1763                     if (s->mb_intra || (dir==1 && s->pict_type != FF_B_TYPE)) {
1764                         motion_x = motion_y = 0;
1765                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1766                         motion_x = s->mv[dir][0][0];
1767                         motion_y = s->mv[dir][0][1];
1768                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1769                         motion_x = s->mv[dir][i][0];
1770                         motion_y = s->mv[dir][i][1];
1771                     }
1772
1773                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1774                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1775                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1776                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1777                     s->current_picture.ref_index [dir][xy    ]=
1778                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
1779                     assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1780                 }
1781                 xy += wrap;
1782             }
1783         }
1784
1785         s->dest[0] += 16 >> lowres;
1786         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1787         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1788
1789         MPV_decode_mb(s, s->block);
1790
1791         if (++s->mb_x >= s->mb_width) {
1792             const int mb_size= 16>>s->avctx->lowres;
1793
1794             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
1795
1796             s->mb_x = 0;
1797             s->mb_y++;
1798
1799             if(s->mb_y<<field_pic >= s->mb_height){
1800                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1801                 int is_d10= s->chroma_format==2 && s->pict_type==FF_I_TYPE && avctx->profile==0 && avctx->level==5
1802                             && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1803                             && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1804
1805                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1806                    || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
1807                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1808                     return -1;
1809                 }else
1810                     goto eos;
1811             }
1812
1813             ff_init_block_index(s);
1814         }
1815
1816         /* skip mb handling */
1817         if (s->mb_skip_run == -1) {
1818             /* read again increment */
1819             s->mb_skip_run = 0;
1820             for(;;) {
1821                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1822                 if (code < 0){
1823                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1824                     return -1;
1825                 }
1826                 if (code >= 33) {
1827                     if (code == 33) {
1828                         s->mb_skip_run += 33;
1829                     }else if(code == 35){
1830                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1831                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1832                             return -1;
1833                         }
1834                         goto eos; /* end of slice */
1835                     }
1836                     /* otherwise, stuffing, nothing to do */
1837                 } else {
1838                     s->mb_skip_run += code;
1839                     break;
1840                 }
1841             }
1842             if(s->mb_skip_run){
1843                 int i;
1844                 if(s->pict_type == FF_I_TYPE){
1845                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1846                     return -1;
1847                 }
1848
1849                 /* skip mb */
1850                 s->mb_intra = 0;
1851                 for(i=0;i<12;i++)
1852                     s->block_last_index[i] = -1;
1853                 if(s->picture_structure == PICT_FRAME)
1854                     s->mv_type = MV_TYPE_16X16;
1855                 else
1856                     s->mv_type = MV_TYPE_FIELD;
1857                 if (s->pict_type == FF_P_TYPE) {
1858                     /* if P type, zero motion vector is implied */
1859                     s->mv_dir = MV_DIR_FORWARD;
1860                     s->mv[0][0][0] = s->mv[0][0][1] = 0;
1861                     s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1862                     s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1863                     s->field_select[0][0]= s->picture_structure - 1;
1864                 } else {
1865                     /* if B type, reuse previous vectors and directions */
1866                     s->mv[0][0][0] = s->last_mv[0][0][0];
1867                     s->mv[0][0][1] = s->last_mv[0][0][1];
1868                     s->mv[1][0][0] = s->last_mv[1][0][0];
1869                     s->mv[1][0][1] = s->last_mv[1][0][1];
1870                 }
1871             }
1872         }
1873     }
1874 eos: // end of slice
1875     *buf += (get_bits_count(&s->gb)-1)/8;
1876 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1877     return 0;
1878 }
1879
1880 static int slice_decode_thread(AVCodecContext *c, void *arg){
1881     MpegEncContext *s= arg;
1882     const uint8_t *buf= s->gb.buffer;
1883     int mb_y= s->start_mb_y;
1884
1885     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
1886
1887     for(;;){
1888         uint32_t start_code;
1889         int ret;
1890
1891         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1892         emms_c();
1893 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1894 //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);
1895         if(ret < 0){
1896             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1897                 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);
1898         }else{
1899             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);
1900         }
1901
1902         if(s->mb_y == s->end_mb_y)
1903             return 0;
1904
1905         start_code= -1;
1906         buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1907         mb_y= start_code - SLICE_MIN_START_CODE;
1908         if(mb_y < 0 || mb_y >= s->end_mb_y)
1909             return -1;
1910     }
1911
1912     return 0; //not reached
1913 }
1914
1915 /**
1916  * handles slice ends.
1917  * @return 1 if it seems to be the last slice of
1918  */
1919 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1920 {
1921     Mpeg1Context *s1 = avctx->priv_data;
1922     MpegEncContext *s = &s1->mpeg_enc_ctx;
1923
1924     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1925         return 0;
1926
1927 #ifdef HAVE_XVMC
1928     if(s->avctx->xvmc_acceleration)
1929         XVMC_field_end(s);
1930 #endif
1931     /* end of slice reached */
1932     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1933         /* end of image */
1934
1935         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1936
1937         ff_er_frame_end(s);
1938
1939         MPV_frame_end(s);
1940
1941         if (s->pict_type == FF_B_TYPE || s->low_delay) {
1942             *pict= *(AVFrame*)s->current_picture_ptr;
1943             ff_print_debug_info(s, pict);
1944         } else {
1945             s->picture_number++;
1946             /* latency of 1 frame for I and P frames */
1947             /* XXX: use another variable than picture_number */
1948             if (s->last_picture_ptr != NULL) {
1949                 *pict= *(AVFrame*)s->last_picture_ptr;
1950                  ff_print_debug_info(s, pict);
1951             }
1952         }
1953
1954         return 1;
1955     } else {
1956         return 0;
1957     }
1958 }
1959
1960 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1961                                  const uint8_t *buf, int buf_size)
1962 {
1963     Mpeg1Context *s1 = avctx->priv_data;
1964     MpegEncContext *s = &s1->mpeg_enc_ctx;
1965     int width,height;
1966     int i, v, j;
1967
1968     init_get_bits(&s->gb, buf, buf_size*8);
1969
1970     width = get_bits(&s->gb, 12);
1971     height = get_bits(&s->gb, 12);
1972     if (width <= 0 || height <= 0)
1973         return -1;
1974     s->aspect_ratio_info= get_bits(&s->gb, 4);
1975     if (s->aspect_ratio_info == 0) {
1976         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1977         if (avctx->error_resilience >= FF_ER_COMPLIANT)
1978             return -1;
1979     }
1980     s->frame_rate_index = get_bits(&s->gb, 4);
1981     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1982         return -1;
1983     s->bit_rate = get_bits(&s->gb, 18) * 400;
1984     if (get_bits1(&s->gb) == 0) /* marker */
1985         return -1;
1986     s->width = width;
1987     s->height = height;
1988
1989     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
1990     skip_bits(&s->gb, 1);
1991
1992     /* get matrix */
1993     if (get_bits1(&s->gb)) {
1994         for(i=0;i<64;i++) {
1995             v = get_bits(&s->gb, 8);
1996             if(v==0){
1997                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
1998                 return -1;
1999             }
2000             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2001             s->intra_matrix[j] = v;
2002             s->chroma_intra_matrix[j] = v;
2003         }
2004 #ifdef DEBUG
2005         dprintf(s->avctx, "intra matrix present\n");
2006         for(i=0;i<64;i++)
2007             dprintf(s->avctx, " %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
2008         dprintf(s->avctx, "\n");
2009 #endif
2010     } else {
2011         for(i=0;i<64;i++) {
2012             j = s->dsp.idct_permutation[i];
2013             v = ff_mpeg1_default_intra_matrix[i];
2014             s->intra_matrix[j] = v;
2015             s->chroma_intra_matrix[j] = v;
2016         }
2017     }
2018     if (get_bits1(&s->gb)) {
2019         for(i=0;i<64;i++) {
2020             v = get_bits(&s->gb, 8);
2021             if(v==0){
2022                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2023                 return -1;
2024             }
2025             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2026             s->inter_matrix[j] = v;
2027             s->chroma_inter_matrix[j] = v;
2028         }
2029 #ifdef DEBUG
2030         dprintf(s->avctx, "non intra matrix present\n");
2031         for(i=0;i<64;i++)
2032             dprintf(s->avctx, " %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
2033         dprintf(s->avctx, "\n");
2034 #endif
2035     } else {
2036         for(i=0;i<64;i++) {
2037             int j= s->dsp.idct_permutation[i];
2038             v = ff_mpeg1_default_non_intra_matrix[i];
2039             s->inter_matrix[j] = v;
2040             s->chroma_inter_matrix[j] = v;
2041         }
2042     }
2043
2044     if(show_bits(&s->gb, 23) != 0){
2045         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2046         return -1;
2047     }
2048
2049     /* we set mpeg2 parameters so that it emulates mpeg1 */
2050     s->progressive_sequence = 1;
2051     s->progressive_frame = 1;
2052     s->picture_structure = PICT_FRAME;
2053     s->frame_pred_frame_dct = 1;
2054     s->chroma_format = 1;
2055     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2056     avctx->sub_id = 1; /* indicates mpeg1 */
2057     s->out_format = FMT_MPEG1;
2058     s->swap_uv = 0;//AFAIK VCR2 don't have SEQ_HEADER
2059     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2060
2061     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2062         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2063                s->avctx->rc_buffer_size, s->bit_rate);
2064
2065     return 0;
2066 }
2067
2068 static int vcr2_init_sequence(AVCodecContext *avctx)
2069 {
2070     Mpeg1Context *s1 = avctx->priv_data;
2071     MpegEncContext *s = &s1->mpeg_enc_ctx;
2072     int i, v;
2073
2074     /* start new mpeg1 context decoding */
2075     s->out_format = FMT_MPEG1;
2076     if (s1->mpeg_enc_ctx_allocated) {
2077         MPV_common_end(s);
2078     }
2079     s->width  = avctx->coded_width;
2080     s->height = avctx->coded_height;
2081     avctx->has_b_frames= 0; //true?
2082     s->low_delay= 1;
2083
2084     if(avctx->xvmc_acceleration){
2085         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2086     }else{
2087         avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2088     }
2089
2090     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2091         if( avctx->idct_algo == FF_IDCT_AUTO )
2092             avctx->idct_algo = FF_IDCT_SIMPLE;
2093
2094     if (MPV_common_init(s) < 0)
2095         return -1;
2096     exchange_uv(s);//common init reset pblocks, so we swap them here
2097     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2098     s1->mpeg_enc_ctx_allocated = 1;
2099
2100     for(i=0;i<64;i++) {
2101         int j= s->dsp.idct_permutation[i];
2102         v = ff_mpeg1_default_intra_matrix[i];
2103         s->intra_matrix[j] = v;
2104         s->chroma_intra_matrix[j] = v;
2105
2106         v = ff_mpeg1_default_non_intra_matrix[i];
2107         s->inter_matrix[j] = v;
2108         s->chroma_inter_matrix[j] = v;
2109     }
2110
2111     s->progressive_sequence = 1;
2112     s->progressive_frame = 1;
2113     s->picture_structure = PICT_FRAME;
2114     s->frame_pred_frame_dct = 1;
2115     s->chroma_format = 1;
2116     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2117     avctx->sub_id = 2; /* indicates mpeg2 */
2118     return 0;
2119 }
2120
2121
2122 static void mpeg_decode_user_data(AVCodecContext *avctx,
2123                                   const uint8_t *buf, int buf_size)
2124 {
2125     const uint8_t *p;
2126     int len, flags;
2127     p = buf;
2128     len = buf_size;
2129
2130     /* we parse the DTG active format information */
2131     if (len >= 5 &&
2132         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2133         flags = p[4];
2134         p += 5;
2135         len -= 5;
2136         if (flags & 0x80) {
2137             /* skip event id */
2138             if (len < 2)
2139                 return;
2140             p += 2;
2141             len -= 2;
2142         }
2143         if (flags & 0x40) {
2144             if (len < 1)
2145                 return;
2146             avctx->dtg_active_format = p[0] & 0x0f;
2147         }
2148     }
2149 }
2150
2151 static void mpeg_decode_gop(AVCodecContext *avctx,
2152                             const uint8_t *buf, int buf_size){
2153     Mpeg1Context *s1 = avctx->priv_data;
2154     MpegEncContext *s = &s1->mpeg_enc_ctx;
2155
2156     int drop_frame_flag;
2157     int time_code_hours, time_code_minutes;
2158     int time_code_seconds, time_code_pictures;
2159     int closed_gop, broken_link;
2160
2161     init_get_bits(&s->gb, buf, buf_size*8);
2162
2163     drop_frame_flag = get_bits1(&s->gb);
2164
2165     time_code_hours=get_bits(&s->gb,5);
2166     time_code_minutes = get_bits(&s->gb,6);
2167     skip_bits1(&s->gb);//marker bit
2168     time_code_seconds = get_bits(&s->gb,6);
2169     time_code_pictures = get_bits(&s->gb,6);
2170
2171     closed_gop  = get_bits1(&s->gb);
2172     /*broken_link indicate that after editing the
2173       reference frames of the first B-Frames after GOP I-Frame
2174       are missing (open gop)*/
2175     broken_link = get_bits1(&s->gb);
2176
2177     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2178         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2179             time_code_hours, time_code_minutes, time_code_seconds,
2180             time_code_pictures, closed_gop, broken_link);
2181 }
2182 /**
2183  * finds the end of the current frame in the bitstream.
2184  * @return the position of the first byte of the next frame, or -1
2185  */
2186 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2187 {
2188     int i;
2189     uint32_t state= pc->state;
2190
2191     /* EOF considered as end of frame */
2192     if (buf_size == 0)
2193         return 0;
2194
2195 /*
2196  0  frame start         -> 1/4
2197  1  first_SEQEXT        -> 0/2
2198  2  first field start   -> 3/0
2199  3  second_SEQEXT       -> 2/0
2200  4  searching end
2201 */
2202
2203     for(i=0; i<buf_size; i++){
2204         assert(pc->frame_start_found>=0 && pc->frame_start_found<=4);
2205         if(pc->frame_start_found&1){
2206             if(state == EXT_START_CODE && (buf[i]&0xF0) != 0x80)
2207                 pc->frame_start_found--;
2208             else if(state == EXT_START_CODE+2){
2209                 if((buf[i]&3) == 3) pc->frame_start_found= 0;
2210                 else                pc->frame_start_found= (pc->frame_start_found+1)&3;
2211             }
2212             state++;
2213         }else{
2214             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2215             if(pc->frame_start_found==0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2216                 i++;
2217                 pc->frame_start_found=4;
2218             }
2219             if(state == SEQ_END_CODE){
2220                 pc->state=-1;
2221                 return i+1;
2222             }
2223             if(pc->frame_start_found==2 && state == SEQ_START_CODE)
2224                 pc->frame_start_found= 0;
2225             if(pc->frame_start_found<4 && state == EXT_START_CODE)
2226                 pc->frame_start_found++;
2227             if(pc->frame_start_found == 4 && (state&0xFFFFFF00) == 0x100){
2228                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2229                     pc->frame_start_found=0;
2230                     pc->state=-1;
2231                     return i-3;
2232                 }
2233             }
2234         }
2235     }
2236     pc->state= state;
2237     return END_NOT_FOUND;
2238 }
2239
2240 static int decode_chunks(AVCodecContext *avctx,
2241                              AVFrame *picture, int *data_size,
2242                              const uint8_t *buf, int buf_size);
2243
2244 /* handle buffering and image synchronisation */
2245 static int mpeg_decode_frame(AVCodecContext *avctx,
2246                              void *data, int *data_size,
2247                              const uint8_t *buf, int buf_size)
2248 {
2249     Mpeg1Context *s = avctx->priv_data;
2250     AVFrame *picture = data;
2251     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2252     dprintf(avctx, "fill_buffer\n");
2253
2254     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2255         /* special case for last picture */
2256         if (s2->low_delay==0 && s2->next_picture_ptr) {
2257             *picture= *(AVFrame*)s2->next_picture_ptr;
2258             s2->next_picture_ptr= NULL;
2259
2260             *data_size = sizeof(AVFrame);
2261         }
2262         return buf_size;
2263     }
2264
2265     if(s2->flags&CODEC_FLAG_TRUNCATED){
2266         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2267
2268         if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2269             return buf_size;
2270     }
2271
2272 #if 0
2273     if (s->repeat_field % 2 == 1) {
2274         s->repeat_field++;
2275         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2276         //        s2->picture_number, s->repeat_field);
2277         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2278             *data_size = sizeof(AVPicture);
2279             goto the_end;
2280         }
2281     }
2282 #endif
2283
2284     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == ff_get_fourcc("VCR2"))
2285         vcr2_init_sequence(avctx);
2286
2287     s->slice_count= 0;
2288
2289     if(avctx->extradata && !avctx->frame_number)
2290         decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
2291
2292     return decode_chunks(avctx, picture, data_size, buf, buf_size);
2293 }
2294
2295 static int decode_chunks(AVCodecContext *avctx,
2296                              AVFrame *picture, int *data_size,
2297                              const uint8_t *buf, int buf_size)
2298 {
2299     Mpeg1Context *s = avctx->priv_data;
2300     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2301     const uint8_t *buf_ptr = buf;
2302     const uint8_t *buf_end = buf + buf_size;
2303     int ret, input_size;
2304
2305     for(;;) {
2306         /* find start next code */
2307         uint32_t start_code = -1;
2308         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2309         if (start_code > 0x1ff){
2310             if(s2->pict_type != FF_B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2311                 if(avctx->thread_count > 1){
2312                     int i;
2313
2314                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count);
2315                     for(i=0; i<s->slice_count; i++)
2316                         s2->error_count += s2->thread_context[i]->error_count;
2317                 }
2318                 if (slice_end(avctx, picture)) {
2319                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2320                         *data_size = sizeof(AVPicture);
2321                 }
2322             }
2323             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2324         }
2325
2326         input_size = buf_end - buf_ptr;
2327
2328         if(avctx->debug & FF_DEBUG_STARTCODE){
2329             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2330         }
2331
2332         /* prepare data for next start code */
2333         switch(start_code) {
2334         case SEQ_START_CODE:
2335             mpeg1_decode_sequence(avctx, buf_ptr,
2336                                     input_size);
2337             break;
2338
2339         case PICTURE_START_CODE:
2340             /* we have a complete image : we try to decompress it */
2341             mpeg1_decode_picture(avctx,
2342                                     buf_ptr, input_size);
2343             break;
2344         case EXT_START_CODE:
2345             mpeg_decode_extension(avctx,
2346                                     buf_ptr, input_size);
2347             break;
2348         case USER_START_CODE:
2349             mpeg_decode_user_data(avctx,
2350                                     buf_ptr, input_size);
2351             break;
2352         case GOP_START_CODE:
2353             s2->first_field=0;
2354             mpeg_decode_gop(avctx,
2355                                     buf_ptr, input_size);
2356             break;
2357         default:
2358             if (start_code >= SLICE_MIN_START_CODE &&
2359                 start_code <= SLICE_MAX_START_CODE) {
2360                 int mb_y= start_code - SLICE_MIN_START_CODE;
2361
2362                 if(s2->last_picture_ptr==NULL){
2363                 /* Skip B-frames if we do not have reference frames. */
2364                     if(s2->pict_type==FF_B_TYPE) break;
2365                 }
2366                 if(s2->next_picture_ptr==NULL){
2367                 /* Skip P-frames if we do not have reference frame no valid header. */
2368                     if(s2->pict_type==FF_P_TYPE && (s2->first_field || s2->picture_structure==PICT_FRAME)) break;
2369                 }
2370                 /* Skip B-frames if we are in a hurry. */
2371                 if(avctx->hurry_up && s2->pict_type==FF_B_TYPE) break;
2372                 if(  (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==FF_B_TYPE)
2373                     ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=FF_I_TYPE)
2374                     || avctx->skip_frame >= AVDISCARD_ALL)
2375                     break;
2376                 /* Skip everything if we are in a hurry>=5. */
2377                 if(avctx->hurry_up>=5) break;
2378
2379                 if (!s->mpeg_enc_ctx_allocated) break;
2380
2381                 if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
2382                     if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2383                         break;
2384                 }
2385
2386                 if(s2->first_slice){
2387                     s2->first_slice=0;
2388                             if(mpeg_field_start(s2) < 0)
2389                         return -1;
2390                     }
2391                 if(!s2->current_picture_ptr){
2392                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2393                     return -1;
2394                 }
2395
2396                 if(avctx->thread_count > 1){
2397                     int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2398                     if(threshold <= mb_y){
2399                         MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2400
2401                         thread_context->start_mb_y= mb_y;
2402                         thread_context->end_mb_y  = s2->mb_height;
2403                         if(s->slice_count){
2404                             s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2405                             ff_update_duplicate_context(thread_context, s2);
2406                         }
2407                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2408                         s->slice_count++;
2409                     }
2410                     buf_ptr += 2; //FIXME add minimum num of bytes per slice
2411                 }else{
2412                     ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2413                     emms_c();
2414
2415                     if(ret < 0){
2416                         if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2417                             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);
2418                     }else{
2419                         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);
2420                     }
2421                 }
2422             }
2423             break;
2424         }
2425     }
2426 }
2427
2428 static int mpeg_decode_end(AVCodecContext *avctx)
2429 {
2430     Mpeg1Context *s = avctx->priv_data;
2431
2432     if (s->mpeg_enc_ctx_allocated)
2433         MPV_common_end(&s->mpeg_enc_ctx);
2434     return 0;
2435 }
2436
2437 AVCodec mpeg1video_decoder = {
2438     "mpeg1video",
2439     CODEC_TYPE_VIDEO,
2440     CODEC_ID_MPEG1VIDEO,
2441     sizeof(Mpeg1Context),
2442     mpeg_decode_init,
2443     NULL,
2444     mpeg_decode_end,
2445     mpeg_decode_frame,
2446     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2447     .flush= ff_mpeg_flush,
2448     .long_name= "MPEG-1 video",
2449 };
2450
2451 AVCodec mpeg2video_decoder = {
2452     "mpeg2video",
2453     CODEC_TYPE_VIDEO,
2454     CODEC_ID_MPEG2VIDEO,
2455     sizeof(Mpeg1Context),
2456     mpeg_decode_init,
2457     NULL,
2458     mpeg_decode_end,
2459     mpeg_decode_frame,
2460     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2461     .flush= ff_mpeg_flush,
2462     .long_name= "MPEG-2 video",
2463 };
2464
2465 //legacy decoder
2466 AVCodec mpegvideo_decoder = {
2467     "mpegvideo",
2468     CODEC_TYPE_VIDEO,
2469     CODEC_ID_MPEG2VIDEO,
2470     sizeof(Mpeg1Context),
2471     mpeg_decode_init,
2472     NULL,
2473     mpeg_decode_end,
2474     mpeg_decode_frame,
2475     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2476     .flush= ff_mpeg_flush,
2477     .long_name= "MPEG-1 video",
2478 };
2479
2480 #ifdef HAVE_XVMC
2481 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx){
2482     Mpeg1Context *s;
2483
2484     if( avctx->thread_count > 1)
2485         return -1;
2486     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2487         return -1;
2488     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2489         dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2490     }
2491     mpeg_decode_init(avctx);
2492     s = avctx->priv_data;
2493
2494     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2495     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2496
2497     return 0;
2498 }
2499
2500 AVCodec mpeg_xvmc_decoder = {
2501     "mpegvideo_xvmc",
2502     CODEC_TYPE_VIDEO,
2503     CODEC_ID_MPEG2VIDEO_XVMC,
2504     sizeof(Mpeg1Context),
2505     mpeg_mc_decode_init,
2506     NULL,
2507     mpeg_decode_end,
2508     mpeg_decode_frame,
2509     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2510     .flush= ff_mpeg_flush,
2511     .long_name = "MPEG-1 video XvMC (X-Video Motion Compensation)",
2512 };
2513
2514 #endif
2515
2516 /* this is ugly i know, but the alternative is too make
2517    hundreds of vars global and prefix them with ff_mpeg1_
2518    which is far uglier. */
2519 #include "mdec.c"