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   1 /*
   2  * MPEG-1/2 decoder
   3  * Copyright (c) 2000,2001 Fabrice Bellard
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file libavcodec/mpeg12.c
  25  * MPEG-1/2 decoder
  26  */
  27
  28 //#define DEBUG
  29 #include "avcodec.h"
  30 #include "dsputil.h"
  31 #include "mpegvideo.h"
  32
  33 #include "mpeg12.h"
  34 #include "mpeg12data.h"
  35 #include "mpeg12decdata.h"
  36 #include "bytestream.h"
  37 #include "vdpau_internal.h"
  38
  39 //#undef NDEBUG
  40 //#include <assert.h>
  41
  42
  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
  49 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
  50                               DCTELEM *block,
  51                               int n);
  52 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
  53 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
  54                                         DCTELEM *block,
  55                                         int n);
  56 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
  57                                     DCTELEM *block,
  58                                     int n);
  59 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
  60 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
  61 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
  62 static void exchange_uv(MpegEncContext *s);
  63
  64 int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
  65 int XVMC_field_end(MpegEncContext *s);
  66 void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
  67 void XVMC_init_block(MpegEncContext *s);//set s->block
  68
  69 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
  70                                            PIX_FMT_XVMC_MPEG2_IDCT,
  71                                            PIX_FMT_XVMC_MPEG2_MC,
  72                                            PIX_FMT_NONE};
  73
  74 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
  75
  76
  77 #define INIT_2D_VLC_RL(rl, static_size)\
  78 {\
  79     static RL_VLC_ELEM rl_vlc_table[static_size];\
  80     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
  81              &rl.table_vlc[0][1], 4, 2,\
  82              &rl.table_vlc[0][0], 4, 2, static_size);\
  83 \
  84     rl.rl_vlc[0]= rl_vlc_table;\
  85     init_2d_vlc_rl(&rl);\
  86 }
  87
  88 static void init_2d_vlc_rl(RLTable *rl)
  89 {
  90     int i;
  91
  92     for(i=0; i<rl->vlc.table_size; i++){
  93         int code= rl->vlc.table[i][0];
  94         int len = rl->vlc.table[i][1];
  95         int level, run;
  96
  97         if(len==0){ // illegal code
  98             run= 65;
  99             level= MAX_LEVEL;
 100         }else if(len<0){ //more bits needed
 101             run= 0;
 102             level= code;
 103         }else{
 104             if(code==rl->n){ //esc
 105                 run= 65;
 106                 level= 0;
 107             }else if(code==rl->n+1){ //eob
 108                 run= 0;
 109                 level= 127;
 110             }else{
 111                 run=   rl->table_run  [code] + 1;
 112                 level= rl->table_level[code];
 113             }
 114         }
 115         rl->rl_vlc[0][i].len= len;
 116         rl->rl_vlc[0][i].level= level;
 117         rl->rl_vlc[0][i].run= run;
 118     }
 119 }
 120
 121 void ff_mpeg12_common_init(MpegEncContext *s)
 122 {
 123
 124     s->y_dc_scale_table=
 125     s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
 126
 127 }
 128
 129 void ff_mpeg1_clean_buffers(MpegEncContext *s){
 130     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
 131     s->last_dc[1] = s->last_dc[0];
 132     s->last_dc[2] = s->last_dc[0];
 133     memset(s->last_mv, 0, sizeof(s->last_mv));
 134 }
 135
 136
 137 /******************************************/
 138 /* decoding */
 139
 140 static VLC mv_vlc;
 141 static VLC mbincr_vlc;
 142 static VLC mb_ptype_vlc;
 143 static VLC mb_btype_vlc;
 144 static VLC mb_pat_vlc;
 145
 146 av_cold void ff_mpeg12_init_vlcs(void)
 147 {
 148     static int done = 0;
 149
 150     if (!done) {
 151         done = 1;
 152
 153         INIT_VLC_STATIC(&dc_lum_vlc, DC_VLC_BITS, 12,
 154                  ff_mpeg12_vlc_dc_lum_bits, 1, 1,
 155                  ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
 156         INIT_VLC_STATIC(&dc_chroma_vlc,  DC_VLC_BITS, 12,
 157                  ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
 158                  ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
 159         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
 160                  &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
 161                  &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
 162         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
 163                  &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
 164                  &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
 165         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
 166                  &ff_mpeg12_mbPatTable[0][1], 2, 1,
 167                  &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
 168
 169         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
 170                  &table_mb_ptype[0][1], 2, 1,
 171                  &table_mb_ptype[0][0], 2, 1, 64);
 172         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
 173                  &table_mb_btype[0][1], 2, 1,
 174                  &table_mb_btype[0][0], 2, 1, 64);
 175         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
 176         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
 177
 178         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
 179         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
 180     }
 181 }
 182
 183 static inline int get_dmv(MpegEncContext *s)
 184 {
 185     if(get_bits1(&s->gb))
 186         return 1 - (get_bits1(&s->gb) << 1);
 187     else
 188         return 0;
 189 }
 190
 191 static inline int get_qscale(MpegEncContext *s)
 192 {
 193     int qscale = get_bits(&s->gb, 5);
 194     if (s->q_scale_type) {
 195         return non_linear_qscale[qscale];
 196     } else {
 197         return qscale << 1;
 198     }
 199 }
 200
 201 /* motion type (for MPEG-2) */
 202 #define MT_FIELD 1
 203 #define MT_FRAME 2
 204 #define MT_16X8  2
 205 #define MT_DMV   3
 206
 207 static int mpeg_decode_mb(MpegEncContext *s,
 208                           DCTELEM block[12][64])
 209 {
 210     int i, j, k, cbp, val, mb_type, motion_type;
 211     const int mb_block_count = 4 + (1<< s->chroma_format);
 212
 213     dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
 214
 215     assert(s->mb_skipped==0);
 216
 217     if (s->mb_skip_run-- != 0) {
 218         if (s->pict_type == FF_P_TYPE) {
 219             s->mb_skipped = 1;
 220             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
 221         } else {
 222             int mb_type;
 223
 224             if(s->mb_x)
 225                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
 226             else
 227                 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
 228             if(IS_INTRA(mb_type))
 229                 return -1;
 230
 231             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
 232                 mb_type | MB_TYPE_SKIP;
 233 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
 234
 235             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
 236                 s->mb_skipped = 1;
 237         }
 238
 239         return 0;
 240     }
 241
 242     switch(s->pict_type) {
 243     default:
 244     case FF_I_TYPE:
 245         if (get_bits1(&s->gb) == 0) {
 246             if (get_bits1(&s->gb) == 0){
 247                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
 248                 return -1;
 249             }
 250             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
 251         } else {
 252             mb_type = MB_TYPE_INTRA;
 253         }
 254         break;
 255     case FF_P_TYPE:
 256         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
 257         if (mb_type < 0){
 258             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
 259             return -1;
 260         }
 261         mb_type = ptype2mb_type[ mb_type ];
 262         break;
 263     case FF_B_TYPE:
 264         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
 265         if (mb_type < 0){
 266             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
 267             return -1;
 268         }
 269         mb_type = btype2mb_type[ mb_type ];
 270         break;
 271     }
 272     dprintf(s->avctx, "mb_type=%x\n", mb_type);
 273 //    motion_type = 0; /* avoid warning */
 274     if (IS_INTRA(mb_type)) {
 275         s->dsp.clear_blocks(s->block[0]);
 276
 277         if(!s->chroma_y_shift){
 278             s->dsp.clear_blocks(s->block[6]);
 279         }
 280
 281         /* compute DCT type */
 282         if (s->picture_structure == PICT_FRAME && //FIXME add an interlaced_dct coded var?
 283             !s->frame_pred_frame_dct) {
 284             s->interlaced_dct = get_bits1(&s->gb);
 285         }
 286
 287         if (IS_QUANT(mb_type))
 288             s->qscale = get_qscale(s);
 289
 290         if (s->concealment_motion_vectors) {
 291             /* just parse them */
 292             if (s->picture_structure != PICT_FRAME)
 293                 skip_bits1(&s->gb); /* field select */
 294
 295             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
 296                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
 297             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
 298                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
 299
 300             skip_bits1(&s->gb); /* marker */
 301         }else
 302             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
 303         s->mb_intra = 1;
 304 #if CONFIG_XVMC
 305         //if 1, we memcpy blocks in xvmcvideo
 306         if(s->avctx->xvmc_acceleration > 1){
 307             XVMC_pack_pblocks(s,-1);//inter are always full blocks
 308             if(s->swap_uv){
 309                 exchange_uv(s);
 310             }
 311         }
 312 #endif
 313
 314         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 315             if(s->flags2 & CODEC_FLAG2_FAST){
 316                 for(i=0;i<6;i++) {
 317                     mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
 318                 }
 319             }else{
 320                 for(i=0;i<mb_block_count;i++) {
 321                     if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
 322                         return -1;
 323                 }
 324             }
 325         } else {
 326             for(i=0;i<6;i++) {
 327                 if (ff_mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
 328                     return -1;
 329             }
 330         }
 331     } else {
 332         if (mb_type & MB_TYPE_ZERO_MV){
 333             assert(mb_type & MB_TYPE_CBP);
 334
 335             s->mv_dir = MV_DIR_FORWARD;
 336             if(s->picture_structure == PICT_FRAME){
 337                 if(!s->frame_pred_frame_dct)
 338                     s->interlaced_dct = get_bits1(&s->gb);
 339                 s->mv_type = MV_TYPE_16X16;
 340             }else{
 341                 s->mv_type = MV_TYPE_FIELD;
 342                 mb_type |= MB_TYPE_INTERLACED;
 343                 s->field_select[0][0]= s->picture_structure - 1;
 344             }
 345
 346             if (IS_QUANT(mb_type))
 347                 s->qscale = get_qscale(s);
 348
 349             s->last_mv[0][0][0] = 0;
 350             s->last_mv[0][0][1] = 0;
 351             s->last_mv[0][1][0] = 0;
 352             s->last_mv[0][1][1] = 0;
 353             s->mv[0][0][0] = 0;
 354             s->mv[0][0][1] = 0;
 355         }else{
 356             assert(mb_type & MB_TYPE_L0L1);
 357 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
 358             /* get additional motion vector type */
 359             if (s->frame_pred_frame_dct)
 360                 motion_type = MT_FRAME;
 361             else{
 362                 motion_type = get_bits(&s->gb, 2);
 363                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
 364                     s->interlaced_dct = get_bits1(&s->gb);
 365             }
 366
 367             if (IS_QUANT(mb_type))
 368                 s->qscale = get_qscale(s);
 369
 370             /* motion vectors */
 371             s->mv_dir= (mb_type>>13)&3;
 372             dprintf(s->avctx, "motion_type=%d\n", motion_type);
 373             switch(motion_type) {
 374             case MT_FRAME: /* or MT_16X8 */
 375                 if (s->picture_structure == PICT_FRAME) {
 376                     mb_type |= MB_TYPE_16x16;
 377                     s->mv_type = MV_TYPE_16X16;
 378                     for(i=0;i<2;i++) {
 379                         if (USES_LIST(mb_type, i)) {
 380                             /* MT_FRAME */
 381                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
 382                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
 383                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
 384                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
 385                             /* full_pel: only for MPEG-1 */
 386                             if (s->full_pel[i]){
 387                                 s->mv[i][0][0] <<= 1;
 388                                 s->mv[i][0][1] <<= 1;
 389                             }
 390                         }
 391                     }
 392                 } else {
 393                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 394                     s->mv_type = MV_TYPE_16X8;
 395                     for(i=0;i<2;i++) {
 396                         if (USES_LIST(mb_type, i)) {
 397                             /* MT_16X8 */
 398                             for(j=0;j<2;j++) {
 399                                 s->field_select[i][j] = get_bits1(&s->gb);
 400                                 for(k=0;k<2;k++) {
 401                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 402                                                              s->last_mv[i][j][k]);
 403                                     s->last_mv[i][j][k] = val;
 404                                     s->mv[i][j][k] = val;
 405                                 }
 406                             }
 407                         }
 408                     }
 409                 }
 410                 break;
 411             case MT_FIELD:
 412                 s->mv_type = MV_TYPE_FIELD;
 413                 if (s->picture_structure == PICT_FRAME) {
 414                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
 415                     for(i=0;i<2;i++) {
 416                         if (USES_LIST(mb_type, i)) {
 417                             for(j=0;j<2;j++) {
 418                                 s->field_select[i][j] = get_bits1(&s->gb);
 419                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 420                                                          s->last_mv[i][j][0]);
 421                                 s->last_mv[i][j][0] = val;
 422                                 s->mv[i][j][0] = val;
 423                                 dprintf(s->avctx, "fmx=%d\n", val);
 424                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 425                                                          s->last_mv[i][j][1] >> 1);
 426                                 s->last_mv[i][j][1] = val << 1;
 427                                 s->mv[i][j][1] = val;
 428                                 dprintf(s->avctx, "fmy=%d\n", val);
 429                             }
 430                         }
 431                     }
 432                 } else {
 433                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 434                     for(i=0;i<2;i++) {
 435                         if (USES_LIST(mb_type, i)) {
 436                             s->field_select[i][0] = get_bits1(&s->gb);
 437                             for(k=0;k<2;k++) {
 438                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
 439                                                          s->last_mv[i][0][k]);
 440                                 s->last_mv[i][0][k] = val;
 441                                 s->last_mv[i][1][k] = val;
 442                                 s->mv[i][0][k] = val;
 443                             }
 444                         }
 445                     }
 446                 }
 447                 break;
 448             case MT_DMV:
 449                 s->mv_type = MV_TYPE_DMV;
 450                 for(i=0;i<2;i++) {
 451                     if (USES_LIST(mb_type, i)) {
 452                         int dmx, dmy, mx, my, m;
 453                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
 454                                                 s->last_mv[i][0][0]);
 455                         s->last_mv[i][0][0] = mx;
 456                         s->last_mv[i][1][0] = mx;
 457                         dmx = get_dmv(s);
 458                         my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
 459                                                 s->last_mv[i][0][1] >> 1);
 460                         dmy = get_dmv(s);
 461
 462
 463                         s->last_mv[i][0][1] = my<<1;
 464                         s->last_mv[i][1][1] = my<<1;
 465
 466                         s->mv[i][0][0] = mx;
 467                         s->mv[i][0][1] = my;
 468                         s->mv[i][1][0] = mx;//not used
 469                         s->mv[i][1][1] = my;//not used
 470
 471                         if (s->picture_structure == PICT_FRAME) {
 472                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
 473
 474                             //m = 1 + 2 * s->top_field_first;
 475                             m = s->top_field_first ? 1 : 3;
 476
 477                             /* top -> top pred */
 478                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 479                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
 480                             m = 4 - m;
 481                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
 482                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
 483                         } else {
 484                             mb_type |= MB_TYPE_16x16;
 485
 486                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
 487                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
 488                             if(s->picture_structure == PICT_TOP_FIELD)
 489                                 s->mv[i][2][1]--;
 490                             else
 491                                 s->mv[i][2][1]++;
 492                         }
 493                     }
 494                 }
 495                 break;
 496             default:
 497                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
 498                 return -1;
 499             }
 500         }
 501
 502         s->mb_intra = 0;
 503         if (HAS_CBP(mb_type)) {
 504             s->dsp.clear_blocks(s->block[0]);
 505
 506             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
 507             if(mb_block_count > 6){
 508                  cbp<<= mb_block_count-6;
 509                  cbp |= get_bits(&s->gb, mb_block_count-6);
 510                  s->dsp.clear_blocks(s->block[6]);
 511             }
 512             if (cbp <= 0){
 513                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
 514                 return -1;
 515             }
 516
 517 #if CONFIG_XVMC
 518             //if 1, we memcpy blocks in xvmcvideo
 519             if(s->avctx->xvmc_acceleration > 1){
 520                 XVMC_pack_pblocks(s,cbp);
 521                 if(s->swap_uv){
 522                     exchange_uv(s);
 523                 }
 524             }
 525 #endif
 526
 527             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
 528                 if(s->flags2 & CODEC_FLAG2_FAST){
 529                     for(i=0;i<6;i++) {
 530                         if(cbp & 32) {
 531                             mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
 532                         } else {
 533                             s->block_last_index[i] = -1;
 534                         }
 535                         cbp+=cbp;
 536                     }
 537                 }else{
 538                     cbp<<= 12-mb_block_count;
 539
 540                     for(i=0;i<mb_block_count;i++) {
 541                         if ( cbp & (1<<11) ) {
 542                             if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
 543                                 return -1;
 544                         } else {
 545                             s->block_last_index[i] = -1;
 546                         }
 547                         cbp+=cbp;
 548                     }
 549                 }
 550             } else {
 551                 if(s->flags2 & CODEC_FLAG2_FAST){
 552                     for(i=0;i<6;i++) {
 553                         if (cbp & 32) {
 554                             mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
 555                         } else {
 556                             s->block_last_index[i] = -1;
 557                         }
 558                         cbp+=cbp;
 559                     }
 560                 }else{
 561                     for(i=0;i<6;i++) {
 562                         if (cbp & 32) {
 563                             if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
 564                                 return -1;
 565                         } else {
 566                             s->block_last_index[i] = -1;
 567                         }
 568                         cbp+=cbp;
 569                     }
 570                 }
 571             }
 572         }else{
 573             for(i=0;i<12;i++)
 574                 s->block_last_index[i] = -1;
 575         }
 576     }
 577
 578     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
 579
 580     return 0;
 581 }
 582
 583 /* as H.263, but only 17 codes */
 584 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
 585 {
 586     int code, sign, val, l, shift;
 587
 588     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
 589     if (code == 0) {
 590         return pred;
 591     }
 592     if (code < 0) {
 593         return 0xffff;
 594     }
 595
 596     sign = get_bits1(&s->gb);
 597     shift = fcode - 1;
 598     val = code;
 599     if (shift) {
 600         val = (val - 1) << shift;
 601         val |= get_bits(&s->gb, shift);
 602         val++;
 603     }
 604     if (sign)
 605         val = -val;
 606     val += pred;
 607
 608     /* modulo decoding */
 609     l= INT_BIT - 5 - shift;
 610     val = (val<<l)>>l;
 611     return val;
 612 }
 613
 614 inline int ff_mpeg1_decode_block_intra(MpegEncContext *s,
 615                                DCTELEM *block,
 616                                int n)
 617 {
 618     int level, dc, diff, i, j, run;
 619     int component;
 620     RLTable *rl = &ff_rl_mpeg1;
 621     uint8_t * const scantable= s->intra_scantable.permutated;
 622     const uint16_t *quant_matrix= s->intra_matrix;
 623     const int qscale= s->qscale;
 624
 625     /* DC coefficient */
 626     component = (n <= 3 ? 0 : n - 4 + 1);
 627     diff = decode_dc(&s->gb, component);
 628     if (diff >= 0xffff)
 629         return -1;
 630     dc = s->last_dc[component];
 631     dc += diff;
 632     s->last_dc[component] = dc;
 633     block[0] = dc<<3;
 634     dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
 635     i = 0;
 636     {
 637         OPEN_READER(re, &s->gb);
 638         /* now quantify & encode AC coefficients */
 639         for(;;) {
 640             UPDATE_CACHE(re, &s->gb);
 641             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 642
 643             if(level == 127){
 644                 break;
 645             } else if(level != 0) {
 646                 i += run;
 647                 j = scantable[i];
 648                 level= (level*qscale*quant_matrix[j])>>4;
 649                 level= (level-1)|1;
 650                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 651                 LAST_SKIP_BITS(re, &s->gb, 1);
 652             } else {
 653                 /* escape */
 654                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 655                 UPDATE_CACHE(re, &s->gb);
 656                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 657                 if (level == -128) {
 658                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
 659                 } else if (level == 0) {
 660                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
 661                 }
 662                 i += run;
 663                 j = scantable[i];
 664                 if(level<0){
 665                     level= -level;
 666                     level= (level*qscale*quant_matrix[j])>>4;
 667                     level= (level-1)|1;
 668                     level= -level;
 669                 }else{
 670                     level= (level*qscale*quant_matrix[j])>>4;
 671                     level= (level-1)|1;
 672                 }
 673             }
 674             if (i > 63){
 675                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 676                 return -1;
 677             }
 678
 679             block[j] = level;
 680         }
 681         CLOSE_READER(re, &s->gb);
 682     }
 683     s->block_last_index[n] = i;
 684    return 0;
 685 }
 686
 687 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
 688                                DCTELEM *block,
 689                                int n)
 690 {
 691     int level, i, j, run;
 692     RLTable *rl = &ff_rl_mpeg1;
 693     uint8_t * const scantable= s->intra_scantable.permutated;
 694     const uint16_t *quant_matrix= s->inter_matrix;
 695     const int qscale= s->qscale;
 696
 697     {
 698         OPEN_READER(re, &s->gb);
 699         i = -1;
 700         // special case for first coefficient, no need to add second VLC table
 701         UPDATE_CACHE(re, &s->gb);
 702         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 703             level= (3*qscale*quant_matrix[0])>>5;
 704             level= (level-1)|1;
 705             if(GET_CACHE(re, &s->gb)&0x40000000)
 706                 level= -level;
 707             block[0] = level;
 708             i++;
 709             SKIP_BITS(re, &s->gb, 2);
 710             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 711                 goto end;
 712         }
 713 #if MIN_CACHE_BITS < 19
 714         UPDATE_CACHE(re, &s->gb);
 715 #endif
 716         /* now quantify & encode AC coefficients */
 717         for(;;) {
 718             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 719
 720             if(level != 0) {
 721                 i += run;
 722                 j = scantable[i];
 723                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 724                 level= (level-1)|1;
 725                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 726                 SKIP_BITS(re, &s->gb, 1);
 727             } else {
 728                 /* escape */
 729                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 730                 UPDATE_CACHE(re, &s->gb);
 731                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 732                 if (level == -128) {
 733                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 734                 } else if (level == 0) {
 735                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 736                 }
 737                 i += run;
 738                 j = scantable[i];
 739                 if(level<0){
 740                     level= -level;
 741                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 742                     level= (level-1)|1;
 743                     level= -level;
 744                 }else{
 745                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 746                     level= (level-1)|1;
 747                 }
 748             }
 749             if (i > 63){
 750                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 751                 return -1;
 752             }
 753
 754             block[j] = level;
 755 #if MIN_CACHE_BITS < 19
 756             UPDATE_CACHE(re, &s->gb);
 757 #endif
 758             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 759                 break;
 760 #if MIN_CACHE_BITS >= 19
 761             UPDATE_CACHE(re, &s->gb);
 762 #endif
 763         }
 764 end:
 765         LAST_SKIP_BITS(re, &s->gb, 2);
 766         CLOSE_READER(re, &s->gb);
 767     }
 768     s->block_last_index[n] = i;
 769     return 0;
 770 }
 771
 772 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
 773 {
 774     int level, i, j, run;
 775     RLTable *rl = &ff_rl_mpeg1;
 776     uint8_t * const scantable= s->intra_scantable.permutated;
 777     const int qscale= s->qscale;
 778
 779     {
 780         OPEN_READER(re, &s->gb);
 781         i = -1;
 782         // special case for first coefficient, no need to add second VLC table
 783         UPDATE_CACHE(re, &s->gb);
 784         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 785             level= (3*qscale)>>1;
 786             level= (level-1)|1;
 787             if(GET_CACHE(re, &s->gb)&0x40000000)
 788                 level= -level;
 789             block[0] = level;
 790             i++;
 791             SKIP_BITS(re, &s->gb, 2);
 792             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 793                 goto end;
 794         }
 795 #if MIN_CACHE_BITS < 19
 796         UPDATE_CACHE(re, &s->gb);
 797 #endif
 798
 799         /* now quantify & encode AC coefficients */
 800         for(;;) {
 801             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 802
 803             if(level != 0) {
 804                 i += run;
 805                 j = scantable[i];
 806                 level= ((level*2+1)*qscale)>>1;
 807                 level= (level-1)|1;
 808                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 809                 SKIP_BITS(re, &s->gb, 1);
 810             } else {
 811                 /* escape */
 812                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 813                 UPDATE_CACHE(re, &s->gb);
 814                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
 815                 if (level == -128) {
 816                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
 817                 } else if (level == 0) {
 818                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
 819                 }
 820                 i += run;
 821                 j = scantable[i];
 822                 if(level<0){
 823                     level= -level;
 824                     level= ((level*2+1)*qscale)>>1;
 825                     level= (level-1)|1;
 826                     level= -level;
 827                 }else{
 828                     level= ((level*2+1)*qscale)>>1;
 829                     level= (level-1)|1;
 830                 }
 831             }
 832
 833             block[j] = level;
 834 #if MIN_CACHE_BITS < 19
 835             UPDATE_CACHE(re, &s->gb);
 836 #endif
 837             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 838                 break;
 839 #if MIN_CACHE_BITS >= 19
 840             UPDATE_CACHE(re, &s->gb);
 841 #endif
 842         }
 843 end:
 844         LAST_SKIP_BITS(re, &s->gb, 2);
 845         CLOSE_READER(re, &s->gb);
 846     }
 847     s->block_last_index[n] = i;
 848     return 0;
 849 }
 850
 851
 852 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
 853                                DCTELEM *block,
 854                                int n)
 855 {
 856     int level, i, j, run;
 857     RLTable *rl = &ff_rl_mpeg1;
 858     uint8_t * const scantable= s->intra_scantable.permutated;
 859     const uint16_t *quant_matrix;
 860     const int qscale= s->qscale;
 861     int mismatch;
 862
 863     mismatch = 1;
 864
 865     {
 866         OPEN_READER(re, &s->gb);
 867         i = -1;
 868         if (n < 4)
 869             quant_matrix = s->inter_matrix;
 870         else
 871             quant_matrix = s->chroma_inter_matrix;
 872
 873         // special case for first coefficient, no need to add second VLC table
 874         UPDATE_CACHE(re, &s->gb);
 875         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 876             level= (3*qscale*quant_matrix[0])>>5;
 877             if(GET_CACHE(re, &s->gb)&0x40000000)
 878                 level= -level;
 879             block[0] = level;
 880             mismatch ^= level;
 881             i++;
 882             SKIP_BITS(re, &s->gb, 2);
 883             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 884                 goto end;
 885         }
 886 #if MIN_CACHE_BITS < 19
 887         UPDATE_CACHE(re, &s->gb);
 888 #endif
 889
 890         /* now quantify & encode AC coefficients */
 891         for(;;) {
 892             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 893
 894             if(level != 0) {
 895                 i += run;
 896                 j = scantable[i];
 897                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 898                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 899                 SKIP_BITS(re, &s->gb, 1);
 900             } else {
 901                 /* escape */
 902                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 903                 UPDATE_CACHE(re, &s->gb);
 904                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 905
 906                 i += run;
 907                 j = scantable[i];
 908                 if(level<0){
 909                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
 910                     level= -level;
 911                 }else{
 912                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
 913                 }
 914             }
 915             if (i > 63){
 916                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
 917                 return -1;
 918             }
 919
 920             mismatch ^= level;
 921             block[j] = level;
 922 #if MIN_CACHE_BITS < 19
 923             UPDATE_CACHE(re, &s->gb);
 924 #endif
 925             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 926                 break;
 927 #if MIN_CACHE_BITS >= 19
 928             UPDATE_CACHE(re, &s->gb);
 929 #endif
 930         }
 931 end:
 932         LAST_SKIP_BITS(re, &s->gb, 2);
 933         CLOSE_READER(re, &s->gb);
 934     }
 935     block[63] ^= (mismatch & 1);
 936
 937     s->block_last_index[n] = i;
 938     return 0;
 939 }
 940
 941 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
 942                                DCTELEM *block,
 943                                int n)
 944 {
 945     int level, i, j, run;
 946     RLTable *rl = &ff_rl_mpeg1;
 947     uint8_t * const scantable= s->intra_scantable.permutated;
 948     const int qscale= s->qscale;
 949     OPEN_READER(re, &s->gb);
 950     i = -1;
 951
 952     // special case for first coefficient, no need to add second VLC table
 953     UPDATE_CACHE(re, &s->gb);
 954     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
 955         level= (3*qscale)>>1;
 956         if(GET_CACHE(re, &s->gb)&0x40000000)
 957             level= -level;
 958         block[0] = level;
 959         i++;
 960         SKIP_BITS(re, &s->gb, 2);
 961         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 962             goto end;
 963     }
 964 #if MIN_CACHE_BITS < 19
 965     UPDATE_CACHE(re, &s->gb);
 966 #endif
 967
 968     /* now quantify & encode AC coefficients */
 969     for(;;) {
 970         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
 971
 972         if(level != 0) {
 973             i += run;
 974             j = scantable[i];
 975             level= ((level*2+1)*qscale)>>1;
 976             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
 977             SKIP_BITS(re, &s->gb, 1);
 978         } else {
 979             /* escape */
 980             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
 981             UPDATE_CACHE(re, &s->gb);
 982             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
 983
 984             i += run;
 985             j = scantable[i];
 986             if(level<0){
 987                 level= ((-level*2+1)*qscale)>>1;
 988                 level= -level;
 989             }else{
 990                 level= ((level*2+1)*qscale)>>1;
 991             }
 992         }
 993
 994         block[j] = level;
 995 #if MIN_CACHE_BITS < 19
 996         UPDATE_CACHE(re, &s->gb);
 997 #endif
 998         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
 999             break;
1000 #if MIN_CACHE_BITS >=19
1001         UPDATE_CACHE(re, &s->gb);
1002 #endif
1003     }
1004 end:
1005     LAST_SKIP_BITS(re, &s->gb, 2);
1006     CLOSE_READER(re, &s->gb);
1007     s->block_last_index[n] = i;
1008     return 0;
1009 }
1010
1011
1012 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1013                                DCTELEM *block,
1014                                int n)
1015 {
1016     int level, dc, diff, i, j, run;
1017     int component;
1018     RLTable *rl;
1019     uint8_t * const scantable= s->intra_scantable.permutated;
1020     const uint16_t *quant_matrix;
1021     const int qscale= s->qscale;
1022     int mismatch;
1023
1024     /* DC coefficient */
1025     if (n < 4){
1026         quant_matrix = s->intra_matrix;
1027         component = 0;
1028     }else{
1029         quant_matrix = s->chroma_intra_matrix;
1030         component = (n&1) + 1;
1031     }
1032     diff = decode_dc(&s->gb, component);
1033     if (diff >= 0xffff)
1034         return -1;
1035     dc = s->last_dc[component];
1036     dc += diff;
1037     s->last_dc[component] = dc;
1038     block[0] = dc << (3 - s->intra_dc_precision);
1039     dprintf(s->avctx, "dc=%d\n", block[0]);
1040     mismatch = block[0] ^ 1;
1041     i = 0;
1042     if (s->intra_vlc_format)
1043         rl = &ff_rl_mpeg2;
1044     else
1045         rl = &ff_rl_mpeg1;
1046
1047     {
1048         OPEN_READER(re, &s->gb);
1049         /* now quantify & encode AC coefficients */
1050         for(;;) {
1051             UPDATE_CACHE(re, &s->gb);
1052             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1053
1054             if(level == 127){
1055                 break;
1056             } else if(level != 0) {
1057                 i += run;
1058                 j = scantable[i];
1059                 level= (level*qscale*quant_matrix[j])>>4;
1060                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1061                 LAST_SKIP_BITS(re, &s->gb, 1);
1062             } else {
1063                 /* escape */
1064                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1065                 UPDATE_CACHE(re, &s->gb);
1066                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1067                 i += run;
1068                 j = scantable[i];
1069                 if(level<0){
1070                     level= (-level*qscale*quant_matrix[j])>>4;
1071                     level= -level;
1072                 }else{
1073                     level= (level*qscale*quant_matrix[j])>>4;
1074                 }
1075             }
1076             if (i > 63){
1077                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1078                 return -1;
1079             }
1080
1081             mismatch^= level;
1082             block[j] = level;
1083         }
1084         CLOSE_READER(re, &s->gb);
1085     }
1086     block[63]^= mismatch&1;
1087
1088     s->block_last_index[n] = i;
1089     return 0;
1090 }
1091
1092 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1093                                DCTELEM *block,
1094                                int n)
1095 {
1096     int level, dc, diff, j, run;
1097     int component;
1098     RLTable *rl;
1099     uint8_t * scantable= s->intra_scantable.permutated;
1100     const uint16_t *quant_matrix;
1101     const int qscale= s->qscale;
1102
1103     /* DC coefficient */
1104     if (n < 4){
1105         quant_matrix = s->intra_matrix;
1106         component = 0;
1107     }else{
1108         quant_matrix = s->chroma_intra_matrix;
1109         component = (n&1) + 1;
1110     }
1111     diff = decode_dc(&s->gb, component);
1112     if (diff >= 0xffff)
1113         return -1;
1114     dc = s->last_dc[component];
1115     dc += diff;
1116     s->last_dc[component] = dc;
1117     block[0] = dc << (3 - s->intra_dc_precision);
1118     if (s->intra_vlc_format)
1119         rl = &ff_rl_mpeg2;
1120     else
1121         rl = &ff_rl_mpeg1;
1122
1123     {
1124         OPEN_READER(re, &s->gb);
1125         /* now quantify & encode AC coefficients */
1126         for(;;) {
1127             UPDATE_CACHE(re, &s->gb);
1128             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1129
1130             if(level == 127){
1131                 break;
1132             } else if(level != 0) {
1133                 scantable += run;
1134                 j = *scantable;
1135                 level= (level*qscale*quant_matrix[j])>>4;
1136                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1137                 LAST_SKIP_BITS(re, &s->gb, 1);
1138             } else {
1139                 /* escape */
1140                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1141                 UPDATE_CACHE(re, &s->gb);
1142                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1143                 scantable += run;
1144                 j = *scantable;
1145                 if(level<0){
1146                     level= (-level*qscale*quant_matrix[j])>>4;
1147                     level= -level;
1148                 }else{
1149                     level= (level*qscale*quant_matrix[j])>>4;
1150                 }
1151             }
1152
1153             block[j] = level;
1154         }
1155         CLOSE_READER(re, &s->gb);
1156     }
1157
1158     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1159     return 0;
1160 }
1161
1162 typedef struct Mpeg1Context {
1163     MpegEncContext mpeg_enc_ctx;
1164     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1165     int repeat_field; /* true if we must repeat the field */
1166     AVPanScan pan_scan; /** some temporary storage for the panscan */
1167     int slice_count;
1168     int swap_uv;//indicate VCR2
1169     int save_aspect_info;
1170     int save_width, save_height;
1171     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
1172
1173 } Mpeg1Context;
1174
1175 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1176 {
1177     Mpeg1Context *s = avctx->priv_data;
1178     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1179     int i;
1180
1181     /* we need some permutation to store matrices,
1182      * until MPV_common_init() sets the real permutation. */
1183     for(i=0;i<64;i++)
1184        s2->dsp.idct_permutation[i]=i;
1185
1186     MPV_decode_defaults(s2);
1187
1188     s->mpeg_enc_ctx.avctx= avctx;
1189     s->mpeg_enc_ctx.flags= avctx->flags;
1190     s->mpeg_enc_ctx.flags2= avctx->flags2;
1191     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1192     ff_mpeg12_init_vlcs();
1193
1194     s->mpeg_enc_ctx_allocated = 0;
1195     s->mpeg_enc_ctx.picture_number = 0;
1196     s->repeat_field = 0;
1197     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1198     return 0;
1199 }
1200
1201 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1202                                      const uint8_t *new_perm){
1203     uint16_t temp_matrix[64];
1204     int i;
1205
1206     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1207
1208     for(i=0;i<64;i++){
1209         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1210     }
1211 }
1212
1213 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx){
1214     Mpeg1Context *s1 = avctx->priv_data;
1215     MpegEncContext *s = &s1->mpeg_enc_ctx;
1216
1217     if(avctx->xvmc_acceleration)
1218         return avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1219     else if(avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU){
1220         if(avctx->codec_id == CODEC_ID_MPEG1VIDEO)
1221             return PIX_FMT_VDPAU_MPEG1;
1222         else
1223             return PIX_FMT_VDPAU_MPEG2;
1224     }else{
1225         if(s->chroma_format <  2)
1226             return PIX_FMT_YUV420P;
1227         else if(s->chroma_format == 2)
1228             return PIX_FMT_YUV422P;
1229         else
1230             return PIX_FMT_YUV444P;
1231     }
1232 }
1233
1234 /* Call this function when we know all parameters.
1235  * It may be called in different places for MPEG-1 and MPEG-2. */
1236 static int mpeg_decode_postinit(AVCodecContext *avctx){
1237     Mpeg1Context *s1 = avctx->priv_data;
1238     MpegEncContext *s = &s1->mpeg_enc_ctx;
1239     uint8_t old_permutation[64];
1240
1241     if (
1242         (s1->mpeg_enc_ctx_allocated == 0)||
1243         avctx->coded_width  != s->width ||
1244         avctx->coded_height != s->height||
1245         s1->save_width != s->width ||
1246         s1->save_height != s->height ||
1247         s1->save_aspect_info != s->aspect_ratio_info||
1248         0)
1249     {
1250
1251         if (s1->mpeg_enc_ctx_allocated) {
1252             ParseContext pc= s->parse_context;
1253             s->parse_context.buffer=0;
1254             MPV_common_end(s);
1255             s->parse_context= pc;
1256         }
1257
1258         if( (s->width == 0 )||(s->height == 0))
1259             return -2;
1260
1261         avcodec_set_dimensions(avctx, s->width, s->height);
1262         avctx->bit_rate = s->bit_rate;
1263         s1->save_aspect_info = s->aspect_ratio_info;
1264         s1->save_width = s->width;
1265         s1->save_height = s->height;
1266
1267         /* low_delay may be forced, in this case we will have B-frames
1268          * that behave like P-frames. */
1269         avctx->has_b_frames = !(s->low_delay);
1270
1271         assert((avctx->sub_id==1) == (avctx->codec_id==CODEC_ID_MPEG1VIDEO));
1272         if(avctx->codec_id==CODEC_ID_MPEG1VIDEO){
1273             //MPEG-1 fps
1274             avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1275             avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1276             //MPEG-1 aspect
1277             avctx->sample_aspect_ratio= av_d2q(
1278                     1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1279
1280         }else{//MPEG-2
1281         //MPEG-2 fps
1282             av_reduce(
1283                 &s->avctx->time_base.den,
1284                 &s->avctx->time_base.num,
1285                 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1286                 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1287                 1<<30);
1288         //MPEG-2 aspect
1289             if(s->aspect_ratio_info > 1){
1290                 //we ignore the spec here as reality does not match the spec, see for example
1291                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1292                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) || 1){
1293                     s->avctx->sample_aspect_ratio=
1294                         av_div_q(
1295                          ff_mpeg2_aspect[s->aspect_ratio_info],
1296                          (AVRational){s->width, s->height}
1297                          );
1298                 }else{
1299                     s->avctx->sample_aspect_ratio=
1300                         av_div_q(
1301                          ff_mpeg2_aspect[s->aspect_ratio_info],
1302                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
1303                         );
1304                 }
1305             }else{
1306                 s->avctx->sample_aspect_ratio=
1307                     ff_mpeg2_aspect[s->aspect_ratio_info];
1308             }
1309         }//MPEG-2
1310
1311         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1312         //until then pix_fmt may be changed right after codec init
1313         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
1314             s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
1315             if( avctx->idct_algo == FF_IDCT_AUTO )
1316                 avctx->idct_algo = FF_IDCT_SIMPLE;
1317
1318         /* Quantization matrices may need reordering
1319          * if DCT permutation is changed. */
1320         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1321
1322         if (MPV_common_init(s) < 0)
1323             return -2;
1324
1325         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
1326         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
1327         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1328         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1329
1330         s1->mpeg_enc_ctx_allocated = 1;
1331     }
1332     return 0;
1333 }
1334
1335 static int mpeg1_decode_picture(AVCodecContext *avctx,
1336                                 const uint8_t *buf, int buf_size)
1337 {
1338     Mpeg1Context *s1 = avctx->priv_data;
1339     MpegEncContext *s = &s1->mpeg_enc_ctx;
1340     int ref, f_code, vbv_delay;
1341
1342     if(mpeg_decode_postinit(s->avctx) < 0)
1343        return -2;
1344
1345     init_get_bits(&s->gb, buf, buf_size*8);
1346
1347     ref = get_bits(&s->gb, 10); /* temporal ref */
1348     s->pict_type = get_bits(&s->gb, 3);
1349     if(s->pict_type == 0 || s->pict_type > 3)
1350         return -1;
1351
1352     vbv_delay= get_bits(&s->gb, 16);
1353     if (s->pict_type == FF_P_TYPE || s->pict_type == FF_B_TYPE) {
1354         s->full_pel[0] = get_bits1(&s->gb);
1355         f_code = get_bits(&s->gb, 3);
1356         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1357             return -1;
1358         s->mpeg_f_code[0][0] = f_code;
1359         s->mpeg_f_code[0][1] = f_code;
1360     }
1361     if (s->pict_type == FF_B_TYPE) {
1362         s->full_pel[1] = get_bits1(&s->gb);
1363         f_code = get_bits(&s->gb, 3);
1364         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
1365             return -1;
1366         s->mpeg_f_code[1][0] = f_code;
1367         s->mpeg_f_code[1][1] = f_code;
1368     }
1369     s->current_picture.pict_type= s->pict_type;
1370     s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1371
1372     if(avctx->debug & FF_DEBUG_PICT_INFO)
1373         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1374
1375     s->y_dc_scale = 8;
1376     s->c_dc_scale = 8;
1377     s->first_slice = 1;
1378     return 0;
1379 }
1380
1381 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1382 {
1383     MpegEncContext *s= &s1->mpeg_enc_ctx;
1384     int horiz_size_ext, vert_size_ext;
1385     int bit_rate_ext;
1386
1387     skip_bits(&s->gb, 1); /* profile and level esc*/
1388     s->avctx->profile= get_bits(&s->gb, 3);
1389     s->avctx->level= get_bits(&s->gb, 4);
1390     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1391     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1392     horiz_size_ext = get_bits(&s->gb, 2);
1393     vert_size_ext = get_bits(&s->gb, 2);
1394     s->width |= (horiz_size_ext << 12);
1395     s->height |= (vert_size_ext << 12);
1396     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1397     s->bit_rate += (bit_rate_ext << 18) * 400;
1398     skip_bits1(&s->gb); /* marker */
1399     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1400
1401     s->low_delay = get_bits1(&s->gb);
1402     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1403
1404     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1405     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1406
1407     dprintf(s->avctx, "sequence extension\n");
1408     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1409     s->avctx->sub_id = 2; /* indicates MPEG-2 found */
1410
1411     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1412         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1413                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1414
1415 }
1416
1417 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1418 {
1419     MpegEncContext *s= &s1->mpeg_enc_ctx;
1420     int color_description, w, h;
1421
1422     skip_bits(&s->gb, 3); /* video format */
1423     color_description= get_bits1(&s->gb);
1424     if(color_description){
1425         skip_bits(&s->gb, 8); /* color primaries */
1426         skip_bits(&s->gb, 8); /* transfer_characteristics */
1427         skip_bits(&s->gb, 8); /* matrix_coefficients */
1428     }
1429     w= get_bits(&s->gb, 14);
1430     skip_bits(&s->gb, 1); //marker
1431     h= get_bits(&s->gb, 14);
1432     skip_bits(&s->gb, 1); //marker
1433
1434     s1->pan_scan.width= 16*w;
1435     s1->pan_scan.height=16*h;
1436
1437     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1438         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1439 }
1440
1441 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1442 {
1443     MpegEncContext *s= &s1->mpeg_enc_ctx;
1444     int i,nofco;
1445
1446     nofco = 1;
1447     if(s->progressive_sequence){
1448         if(s->repeat_first_field){
1449             nofco++;
1450             if(s->top_field_first)
1451                 nofco++;
1452         }
1453     }else{
1454         if(s->picture_structure == PICT_FRAME){
1455             nofco++;
1456             if(s->repeat_first_field)
1457                 nofco++;
1458         }
1459     }
1460     for(i=0; i<nofco; i++){
1461         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1462         skip_bits(&s->gb, 1); //marker
1463         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1464         skip_bits(&s->gb, 1); //marker
1465     }
1466
1467     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1468         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1469             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1470             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1471             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1472         );
1473 }
1474
1475 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1476 {
1477     int i, v, j;
1478
1479     dprintf(s->avctx, "matrix extension\n");
1480
1481     if (get_bits1(&s->gb)) {
1482         for(i=0;i<64;i++) {
1483             v = get_bits(&s->gb, 8);
1484             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1485             s->intra_matrix[j] = v;
1486             s->chroma_intra_matrix[j] = v;
1487         }
1488     }
1489     if (get_bits1(&s->gb)) {
1490         for(i=0;i<64;i++) {
1491             v = get_bits(&s->gb, 8);
1492             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1493             s->inter_matrix[j] = v;
1494             s->chroma_inter_matrix[j] = v;
1495         }
1496     }
1497     if (get_bits1(&s->gb)) {
1498         for(i=0;i<64;i++) {
1499             v = get_bits(&s->gb, 8);
1500             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1501             s->chroma_intra_matrix[j] = v;
1502         }
1503     }
1504     if (get_bits1(&s->gb)) {
1505         for(i=0;i<64;i++) {
1506             v = get_bits(&s->gb, 8);
1507             j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1508             s->chroma_inter_matrix[j] = v;
1509         }
1510     }
1511 }
1512
1513 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1514 {
1515     MpegEncContext *s= &s1->mpeg_enc_ctx;
1516
1517     s->full_pel[0] = s->full_pel[1] = 0;
1518     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1519     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1520     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1521     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1522     if(!s->pict_type && s1->mpeg_enc_ctx_allocated){
1523         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1524         if(s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1]==15){
1525             if(s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1526                 s->pict_type= FF_I_TYPE;
1527             else
1528                 s->pict_type= FF_P_TYPE;
1529         }else
1530             s->pict_type= FF_B_TYPE;
1531         s->current_picture.pict_type= s->pict_type;
1532         s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
1533         s->first_slice= 1;
1534     }
1535     s->intra_dc_precision = get_bits(&s->gb, 2);
1536     s->picture_structure = get_bits(&s->gb, 2);
1537     s->top_field_first = get_bits1(&s->gb);
1538     s->frame_pred_frame_dct = get_bits1(&s->gb);
1539     s->concealment_motion_vectors = get_bits1(&s->gb);
1540     s->q_scale_type = get_bits1(&s->gb);
1541     s->intra_vlc_format = get_bits1(&s->gb);
1542     s->alternate_scan = get_bits1(&s->gb);
1543     s->repeat_first_field = get_bits1(&s->gb);
1544     s->chroma_420_type = get_bits1(&s->gb);
1545     s->progressive_frame = get_bits1(&s->gb);
1546
1547     if(s->picture_structure == PICT_FRAME){
1548         s->first_field=0;
1549         s->v_edge_pos= 16*s->mb_height;
1550     }else{
1551         s->first_field ^= 1;
1552         s->v_edge_pos=  8*s->mb_height;
1553         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1554     }
1555
1556     if(s->alternate_scan){
1557         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
1558         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
1559     }else{
1560         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
1561         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
1562     }
1563
1564     /* composite display not parsed */
1565     dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1566     dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1567     dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1568     dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1569     dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1570     dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1571     dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1572     dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1573     dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1574 }
1575
1576 static void mpeg_decode_extension(AVCodecContext *avctx,
1577                                   const uint8_t *buf, int buf_size)
1578 {
1579     Mpeg1Context *s1 = avctx->priv_data;
1580     MpegEncContext *s = &s1->mpeg_enc_ctx;
1581     int ext_type;
1582
1583     init_get_bits(&s->gb, buf, buf_size*8);
1584
1585     ext_type = get_bits(&s->gb, 4);
1586     switch(ext_type) {
1587     case 0x1:
1588         mpeg_decode_sequence_extension(s1);
1589         break;
1590     case 0x2:
1591         mpeg_decode_sequence_display_extension(s1);
1592         break;
1593     case 0x3:
1594         mpeg_decode_quant_matrix_extension(s);
1595         break;
1596     case 0x7:
1597         mpeg_decode_picture_display_extension(s1);
1598         break;
1599     case 0x8:
1600         mpeg_decode_picture_coding_extension(s1);
1601         break;
1602     }
1603 }
1604
1605 static void exchange_uv(MpegEncContext *s){
1606     short * tmp = s->pblocks[4];
1607     s->pblocks[4] = s->pblocks[5];
1608     s->pblocks[5] = tmp;
1609 }
1610
1611 static int mpeg_field_start(MpegEncContext *s){
1612     AVCodecContext *avctx= s->avctx;
1613     Mpeg1Context *s1 = (Mpeg1Context*)s;
1614
1615     /* start frame decoding */
1616     if(s->first_field || s->picture_structure==PICT_FRAME){
1617         if(MPV_frame_start(s, avctx) < 0)
1618             return -1;
1619
1620         ff_er_frame_start(s);
1621
1622         /* first check if we must repeat the frame */
1623         s->current_picture_ptr->repeat_pict = 0;
1624         if (s->repeat_first_field) {
1625             if (s->progressive_sequence) {
1626                 if (s->top_field_first)
1627                     s->current_picture_ptr->repeat_pict = 4;
1628                 else
1629                     s->current_picture_ptr->repeat_pict = 2;
1630             } else if (s->progressive_frame) {
1631                 s->current_picture_ptr->repeat_pict = 1;
1632             }
1633         }
1634
1635         *s->current_picture_ptr->pan_scan= s1->pan_scan;
1636     }else{ //second field
1637             int i;
1638
1639             if(!s->current_picture_ptr){
1640                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1641                 return -1;
1642             }
1643
1644             for(i=0; i<4; i++){
1645                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1646                 if(s->picture_structure == PICT_BOTTOM_FIELD){
1647                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1648                 }
1649             }
1650     }
1651 #if CONFIG_XVMC
1652 // MPV_frame_start will call this function too,
1653 // but we need to call it on every field
1654     if(s->avctx->xvmc_acceleration)
1655          XVMC_field_start(s,avctx);
1656 #endif
1657
1658     return 0;
1659 }
1660
1661 #define DECODE_SLICE_ERROR -1
1662 #define DECODE_SLICE_OK 0
1663
1664 /**
1665  * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1666  * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1667  *         DECODE_SLICE_OK if this slice is ok<br>
1668  */
1669 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1670                              const uint8_t **buf, int buf_size)
1671 {
1672     MpegEncContext *s = &s1->mpeg_enc_ctx;
1673     AVCodecContext *avctx= s->avctx;
1674     const int field_pic= s->picture_structure != PICT_FRAME;
1675     const int lowres= s->avctx->lowres;
1676
1677     s->resync_mb_x=
1678     s->resync_mb_y= -1;
1679
1680     if (mb_y<<field_pic >= s->mb_height){
1681         av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
1682         return -1;
1683     }
1684
1685     init_get_bits(&s->gb, *buf, buf_size*8);
1686
1687     ff_mpeg1_clean_buffers(s);
1688     s->interlaced_dct = 0;
1689
1690     s->qscale = get_qscale(s);
1691
1692     if(s->qscale == 0){
1693         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1694         return -1;
1695     }
1696
1697     /* extra slice info */
1698     while (get_bits1(&s->gb) != 0) {
1699         skip_bits(&s->gb, 8);
1700     }
1701
1702     s->mb_x=0;
1703
1704     for(;;) {
1705         int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1706         if (code < 0){
1707             av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1708             return -1;
1709         }
1710         if (code >= 33) {
1711             if (code == 33) {
1712                 s->mb_x += 33;
1713             }
1714             /* otherwise, stuffing, nothing to do */
1715         } else {
1716             s->mb_x += code;
1717             break;
1718         }
1719     }
1720     if(s->mb_x >= (unsigned)s->mb_width){
1721         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1722         return -1;
1723     }
1724
1725     s->resync_mb_x= s->mb_x;
1726     s->resync_mb_y= s->mb_y= mb_y;
1727     s->mb_skip_run= 0;
1728     ff_init_block_index(s);
1729
1730     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1731         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1732              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",
1733                  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],
1734                  s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
1735                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1736                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1737                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1738         }
1739     }
1740
1741     for(;;) {
1742 #if CONFIG_XVMC
1743         //If 1, we memcpy blocks in xvmcvideo.
1744         if(s->avctx->xvmc_acceleration > 1)
1745             XVMC_init_block(s);//set s->block
1746 #endif
1747
1748         if(mpeg_decode_mb(s, s->block) < 0)
1749             return -1;
1750
1751         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1752             const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
1753             int xy = s->mb_x*2 + s->mb_y*2*wrap;
1754             int motion_x, motion_y, dir, i;
1755             if(field_pic && !s->first_field)
1756                 xy += wrap/2;
1757
1758             for(i=0; i<2; i++){
1759                 for(dir=0; dir<2; dir++){
1760                     if (s->mb_intra || (dir==1 && s->pict_type != FF_B_TYPE)) {
1761                         motion_x = motion_y = 0;
1762                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1763                         motion_x = s->mv[dir][0][0];
1764                         motion_y = s->mv[dir][0][1];
1765                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1766                         motion_x = s->mv[dir][i][0];
1767                         motion_y = s->mv[dir][i][1];
1768                     }
1769
1770                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1771                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1772                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1773                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1774                     s->current_picture.ref_index [dir][xy    ]=
1775                     s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
1776                     assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1777                 }
1778                 xy += wrap;
1779             }
1780         }
1781
1782         s->dest[0] += 16 >> lowres;
1783         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1784         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1785
1786         MPV_decode_mb(s, s->block);
1787
1788         if (++s->mb_x >= s->mb_width) {
1789             const int mb_size= 16>>s->avctx->lowres;
1790
1791             ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
1792
1793             s->mb_x = 0;
1794             s->mb_y++;
1795
1796             if(s->mb_y<<field_pic >= s->mb_height){
1797                 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1798                 int is_d10= s->chroma_format==2 && s->pict_type==FF_I_TYPE && avctx->profile==0 && avctx->level==5
1799                             && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1800                             && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1801
1802                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1803                    || (avctx->error_recognition >= FF_ER_AGGRESSIVE && left>8)){
1804                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1805                     return -1;
1806                 }else
1807                     goto eos;
1808             }
1809
1810             ff_init_block_index(s);
1811         }
1812
1813         /* skip mb handling */
1814         if (s->mb_skip_run == -1) {
1815             /* read increment again */
1816             s->mb_skip_run = 0;
1817             for(;;) {
1818                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1819                 if (code < 0){
1820                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1821                     return -1;
1822                 }
1823                 if (code >= 33) {
1824                     if (code == 33) {
1825                         s->mb_skip_run += 33;
1826                     }else if(code == 35){
1827                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1828                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1829                             return -1;
1830                         }
1831                         goto eos; /* end of slice */
1832                     }
1833                     /* otherwise, stuffing, nothing to do */
1834                 } else {
1835                     s->mb_skip_run += code;
1836                     break;
1837                 }
1838             }
1839             if(s->mb_skip_run){
1840                 int i;
1841                 if(s->pict_type == FF_I_TYPE){
1842                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1843                     return -1;
1844                 }
1845
1846                 /* skip mb */
1847                 s->mb_intra = 0;
1848                 for(i=0;i<12;i++)
1849                     s->block_last_index[i] = -1;
1850                 if(s->picture_structure == PICT_FRAME)
1851                     s->mv_type = MV_TYPE_16X16;
1852                 else
1853                     s->mv_type = MV_TYPE_FIELD;
1854                 if (s->pict_type == FF_P_TYPE) {
1855                     /* if P type, zero motion vector is implied */
1856                     s->mv_dir = MV_DIR_FORWARD;
1857                     s->mv[0][0][0] = s->mv[0][0][1] = 0;
1858                     s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1859                     s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1860                     s->field_select[0][0]= s->picture_structure - 1;
1861                 } else {
1862                     /* if B type, reuse previous vectors and directions */
1863                     s->mv[0][0][0] = s->last_mv[0][0][0];
1864                     s->mv[0][0][1] = s->last_mv[0][0][1];
1865                     s->mv[1][0][0] = s->last_mv[1][0][0];
1866                     s->mv[1][0][1] = s->last_mv[1][0][1];
1867                 }
1868             }
1869         }
1870     }
1871 eos: // end of slice
1872     *buf += (get_bits_count(&s->gb)-1)/8;
1873 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1874     return 0;
1875 }
1876
1877 static int slice_decode_thread(AVCodecContext *c, void *arg){
1878     MpegEncContext *s= *(void**)arg;
1879     const uint8_t *buf= s->gb.buffer;
1880     int mb_y= s->start_mb_y;
1881
1882     s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
1883
1884     for(;;){
1885         uint32_t start_code;
1886         int ret;
1887
1888         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1889         emms_c();
1890 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1891 //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);
1892         if(ret < 0){
1893             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1894                 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);
1895         }else{
1896             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);
1897         }
1898
1899         if(s->mb_y == s->end_mb_y)
1900             return 0;
1901
1902         start_code= -1;
1903         buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1904         mb_y= start_code - SLICE_MIN_START_CODE;
1905         if(mb_y < 0 || mb_y >= s->end_mb_y)
1906             return -1;
1907     }
1908
1909     return 0; //not reached
1910 }
1911
1912 /**
1913  * Handles slice ends.
1914  * @return 1 if it seems to be the last slice
1915  */
1916 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1917 {
1918     Mpeg1Context *s1 = avctx->priv_data;
1919     MpegEncContext *s = &s1->mpeg_enc_ctx;
1920
1921     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1922         return 0;
1923
1924 #if CONFIG_XVMC
1925     if(s->avctx->xvmc_acceleration)
1926         XVMC_field_end(s);
1927 #endif
1928     /* end of slice reached */
1929     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1930         /* end of image */
1931
1932         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1933
1934         ff_er_frame_end(s);
1935
1936         MPV_frame_end(s);
1937
1938         if (s->pict_type == FF_B_TYPE || s->low_delay) {
1939             *pict= *(AVFrame*)s->current_picture_ptr;
1940             ff_print_debug_info(s, pict);
1941         } else {
1942             s->picture_number++;
1943             /* latency of 1 frame for I- and P-frames */
1944             /* XXX: use another variable than picture_number */
1945             if (s->last_picture_ptr != NULL) {
1946                 *pict= *(AVFrame*)s->last_picture_ptr;
1947                  ff_print_debug_info(s, pict);
1948             }
1949         }
1950
1951         return 1;
1952     } else {
1953         return 0;
1954     }
1955 }
1956
1957 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1958                                  const uint8_t *buf, int buf_size)
1959 {
1960     Mpeg1Context *s1 = avctx->priv_data;
1961     MpegEncContext *s = &s1->mpeg_enc_ctx;
1962     int width,height;
1963     int i, v, j;
1964
1965     init_get_bits(&s->gb, buf, buf_size*8);
1966
1967     width = get_bits(&s->gb, 12);
1968     height = get_bits(&s->gb, 12);
1969     if (width <= 0 || height <= 0)
1970         return -1;
1971     s->aspect_ratio_info= get_bits(&s->gb, 4);
1972     if (s->aspect_ratio_info == 0) {
1973         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1974         if (avctx->error_recognition >= FF_ER_COMPLIANT)
1975             return -1;
1976     }
1977     s->frame_rate_index = get_bits(&s->gb, 4);
1978     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1979         return -1;
1980     s->bit_rate = get_bits(&s->gb, 18) * 400;
1981     if (get_bits1(&s->gb) == 0) /* marker */
1982         return -1;
1983     s->width = width;
1984     s->height = height;
1985
1986     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
1987     skip_bits(&s->gb, 1);
1988
1989     /* get matrix */
1990     if (get_bits1(&s->gb)) {
1991         for(i=0;i<64;i++) {
1992             v = get_bits(&s->gb, 8);
1993             if(v==0){
1994                 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
1995                 return -1;
1996             }
1997             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1998             s->intra_matrix[j] = v;
1999             s->chroma_intra_matrix[j] = v;
2000         }
2001 #ifdef DEBUG
2002         dprintf(s->avctx, "intra matrix present\n");
2003         for(i=0;i<64;i++)
2004             dprintf(s->avctx, " %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
2005         dprintf(s->avctx, "\n");
2006 #endif
2007     } else {
2008         for(i=0;i<64;i++) {
2009             j = s->dsp.idct_permutation[i];
2010             v = ff_mpeg1_default_intra_matrix[i];
2011             s->intra_matrix[j] = v;
2012             s->chroma_intra_matrix[j] = v;
2013         }
2014     }
2015     if (get_bits1(&s->gb)) {
2016         for(i=0;i<64;i++) {
2017             v = get_bits(&s->gb, 8);
2018             if(v==0){
2019                 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2020                 return -1;
2021             }
2022             j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2023             s->inter_matrix[j] = v;
2024             s->chroma_inter_matrix[j] = v;
2025         }
2026 #ifdef DEBUG
2027         dprintf(s->avctx, "non-intra matrix present\n");
2028         for(i=0;i<64;i++)
2029             dprintf(s->avctx, " %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
2030         dprintf(s->avctx, "\n");
2031 #endif
2032     } else {
2033         for(i=0;i<64;i++) {
2034             int j= s->dsp.idct_permutation[i];
2035             v = ff_mpeg1_default_non_intra_matrix[i];
2036             s->inter_matrix[j] = v;
2037             s->chroma_inter_matrix[j] = v;
2038         }
2039     }
2040
2041     if(show_bits(&s->gb, 23) != 0){
2042         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2043         return -1;
2044     }
2045
2046     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
2047     s->progressive_sequence = 1;
2048     s->progressive_frame = 1;
2049     s->picture_structure = PICT_FRAME;
2050     s->frame_pred_frame_dct = 1;
2051     s->chroma_format = 1;
2052     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2053     avctx->sub_id = 1; /* indicates MPEG-1 */
2054     s->out_format = FMT_MPEG1;
2055     s->swap_uv = 0;//AFAIK VCR2 does not have SEQ_HEADER
2056     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2057
2058     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2059         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2060                s->avctx->rc_buffer_size, s->bit_rate);
2061
2062     return 0;
2063 }
2064
2065 static int vcr2_init_sequence(AVCodecContext *avctx)
2066 {
2067     Mpeg1Context *s1 = avctx->priv_data;
2068     MpegEncContext *s = &s1->mpeg_enc_ctx;
2069     int i, v;
2070
2071     /* start new MPEG-1 context decoding */
2072     s->out_format = FMT_MPEG1;
2073     if (s1->mpeg_enc_ctx_allocated) {
2074         MPV_common_end(s);
2075     }
2076     s->width  = avctx->coded_width;
2077     s->height = avctx->coded_height;
2078     avctx->has_b_frames= 0; //true?
2079     s->low_delay= 1;
2080
2081     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2082
2083     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
2084         s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
2085         if( avctx->idct_algo == FF_IDCT_AUTO )
2086             avctx->idct_algo = FF_IDCT_SIMPLE;
2087
2088     if (MPV_common_init(s) < 0)
2089         return -1;
2090     exchange_uv(s);//common init reset pblocks, so we swap them here
2091     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2092     s1->mpeg_enc_ctx_allocated = 1;
2093
2094     for(i=0;i<64;i++) {
2095         int j= s->dsp.idct_permutation[i];
2096         v = ff_mpeg1_default_intra_matrix[i];
2097         s->intra_matrix[j] = v;
2098         s->chroma_intra_matrix[j] = v;
2099
2100         v = ff_mpeg1_default_non_intra_matrix[i];
2101         s->inter_matrix[j] = v;
2102         s->chroma_inter_matrix[j] = v;
2103     }
2104
2105     s->progressive_sequence = 1;
2106     s->progressive_frame = 1;
2107     s->picture_structure = PICT_FRAME;
2108     s->frame_pred_frame_dct = 1;
2109     s->chroma_format = 1;
2110     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2111     avctx->sub_id = 2; /* indicates MPEG-2 */
2112     return 0;
2113 }
2114
2115
2116 static void mpeg_decode_user_data(AVCodecContext *avctx,
2117                                   const uint8_t *buf, int buf_size)
2118 {
2119     const uint8_t *p;
2120     int len, flags;
2121     p = buf;
2122     len = buf_size;
2123
2124     /* we parse the DTG active format information */
2125     if (len >= 5 &&
2126         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2127         flags = p[4];
2128         p += 5;
2129         len -= 5;
2130         if (flags & 0x80) {
2131             /* skip event id */
2132             if (len < 2)
2133                 return;
2134             p += 2;
2135             len -= 2;
2136         }
2137         if (flags & 0x40) {
2138             if (len < 1)
2139                 return;
2140             avctx->dtg_active_format = p[0] & 0x0f;
2141         }
2142     }
2143 }
2144
2145 static void mpeg_decode_gop(AVCodecContext *avctx,
2146                             const uint8_t *buf, int buf_size){
2147     Mpeg1Context *s1 = avctx->priv_data;
2148     MpegEncContext *s = &s1->mpeg_enc_ctx;
2149
2150     int drop_frame_flag;
2151     int time_code_hours, time_code_minutes;
2152     int time_code_seconds, time_code_pictures;
2153     int closed_gop, broken_link;
2154
2155     init_get_bits(&s->gb, buf, buf_size*8);
2156
2157     drop_frame_flag = get_bits1(&s->gb);
2158
2159     time_code_hours=get_bits(&s->gb,5);
2160     time_code_minutes = get_bits(&s->gb,6);
2161     skip_bits1(&s->gb);//marker bit
2162     time_code_seconds = get_bits(&s->gb,6);
2163     time_code_pictures = get_bits(&s->gb,6);
2164
2165     closed_gop  = get_bits1(&s->gb);
2166     /*broken_link indicate that after editing the
2167       reference frames of the first B-Frames after GOP I-Frame
2168       are missing (open gop)*/
2169     broken_link = get_bits1(&s->gb);
2170
2171     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2172         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2173             time_code_hours, time_code_minutes, time_code_seconds,
2174             time_code_pictures, closed_gop, broken_link);
2175 }
2176 /**
2177  * Finds the end of the current frame in the bitstream.
2178  * @return the position of the first byte of the next frame, or -1
2179  */
2180 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2181 {
2182     int i;
2183     uint32_t state= pc->state;
2184
2185     /* EOF considered as end of frame */
2186     if (buf_size == 0)
2187         return 0;
2188
2189 /*
2190  0  frame start         -> 1/4
2191  1  first_SEQEXT        -> 0/2
2192  2  first field start   -> 3/0
2193  3  second_SEQEXT       -> 2/0
2194  4  searching end
2195 */
2196
2197     for(i=0; i<buf_size; i++){
2198         assert(pc->frame_start_found>=0 && pc->frame_start_found<=4);
2199         if(pc->frame_start_found&1){
2200             if(state == EXT_START_CODE && (buf[i]&0xF0) != 0x80)
2201                 pc->frame_start_found--;
2202             else if(state == EXT_START_CODE+2){
2203                 if((buf[i]&3) == 3) pc->frame_start_found= 0;
2204                 else                pc->frame_start_found= (pc->frame_start_found+1)&3;
2205             }
2206             state++;
2207         }else{
2208             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2209             if(pc->frame_start_found==0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2210                 i++;
2211                 pc->frame_start_found=4;
2212             }
2213             if(state == SEQ_END_CODE){
2214                 pc->state=-1;
2215                 return i+1;
2216             }
2217             if(pc->frame_start_found==2 && state == SEQ_START_CODE)
2218                 pc->frame_start_found= 0;
2219             if(pc->frame_start_found<4 && state == EXT_START_CODE)
2220                 pc->frame_start_found++;
2221             if(pc->frame_start_found == 4 && (state&0xFFFFFF00) == 0x100){
2222                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2223                     pc->frame_start_found=0;
2224                     pc->state=-1;
2225                     return i-3;
2226                 }
2227             }
2228         }
2229     }
2230     pc->state= state;
2231     return END_NOT_FOUND;
2232 }
2233
2234 static int decode_chunks(AVCodecContext *avctx,
2235                              AVFrame *picture, int *data_size,
2236                              const uint8_t *buf, int buf_size);
2237
2238 /* handle buffering and image synchronisation */
2239 static int mpeg_decode_frame(AVCodecContext *avctx,
2240                              void *data, int *data_size,
2241                              const uint8_t *buf, int buf_size)
2242 {
2243     Mpeg1Context *s = avctx->priv_data;
2244     AVFrame *picture = data;
2245     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2246     dprintf(avctx, "fill_buffer\n");
2247
2248     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2249         /* special case for last picture */
2250         if (s2->low_delay==0 && s2->next_picture_ptr) {
2251             *picture= *(AVFrame*)s2->next_picture_ptr;
2252             s2->next_picture_ptr= NULL;
2253
2254             *data_size = sizeof(AVFrame);
2255         }
2256         return buf_size;
2257     }
2258
2259     if(s2->flags&CODEC_FLAG_TRUNCATED){
2260         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2261
2262         if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2263             return buf_size;
2264     }
2265
2266 #if 0
2267     if (s->repeat_field % 2 == 1) {
2268         s->repeat_field++;
2269         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2270         //        s2->picture_number, s->repeat_field);
2271         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2272             *data_size = sizeof(AVPicture);
2273             goto the_end;
2274         }
2275     }
2276 #endif
2277
2278     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == AV_RL32("VCR2"))
2279         vcr2_init_sequence(avctx);
2280
2281     s->slice_count= 0;
2282
2283     if(avctx->extradata && !avctx->frame_number)
2284         decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
2285
2286     return decode_chunks(avctx, picture, data_size, buf, buf_size);
2287 }
2288
2289 static int decode_chunks(AVCodecContext *avctx,
2290                              AVFrame *picture, int *data_size,
2291                              const uint8_t *buf, int buf_size)
2292 {
2293     Mpeg1Context *s = avctx->priv_data;
2294     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2295     const uint8_t *buf_ptr = buf;
2296     const uint8_t *buf_end = buf + buf_size;
2297     int ret, input_size;
2298
2299     for(;;) {
2300         /* find next start code */
2301         uint32_t start_code = -1;
2302         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2303         if (start_code > 0x1ff){
2304             if(s2->pict_type != FF_B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2305                 if(avctx->thread_count > 1){
2306                     int i;
2307
2308                     avctx->execute(avctx, slice_decode_thread,  (void**)&(s2->thread_context[0]), NULL, s->slice_count, sizeof(void*));
2309                     for(i=0; i<s->slice_count; i++)
2310                         s2->error_count += s2->thread_context[i]->error_count;
2311                 }
2312
2313                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
2314                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2315
2316                 if (slice_end(avctx, picture)) {
2317                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2318                         *data_size = sizeof(AVPicture);
2319                 }
2320             }
2321             s2->pict_type= 0;
2322             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2323         }
2324
2325         input_size = buf_end - buf_ptr;
2326
2327         if(avctx->debug & FF_DEBUG_STARTCODE){
2328             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2329         }
2330
2331         /* prepare data for next start code */
2332         switch(start_code) {
2333         case SEQ_START_CODE:
2334             mpeg1_decode_sequence(avctx, buf_ptr,
2335                                     input_size);
2336             break;
2337
2338         case PICTURE_START_CODE:
2339             /* we have a complete image: we try to decompress it */
2340             if(mpeg1_decode_picture(avctx,
2341                                     buf_ptr, input_size) < 0)
2342                 s2->pict_type=0;
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 a reference frame or we have an invalid 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->pict_type){
2387                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2388                     break;
2389                 }
2390
2391                 if(s2->first_slice){
2392                     s2->first_slice=0;
2393                             if(mpeg_field_start(s2) < 0)
2394                         return -1;
2395                     }
2396                 if(!s2->current_picture_ptr){
2397                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2398                     return -1;
2399                 }
2400
2401                 if (avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU) {
2402                     s->slice_count++;
2403                     break;
2404                 }
2405
2406                 if(avctx->thread_count > 1){
2407                     int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2408                     if(threshold <= mb_y){
2409                         MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2410
2411                         thread_context->start_mb_y= mb_y;
2412                         thread_context->end_mb_y  = s2->mb_height;
2413                         if(s->slice_count){
2414                             s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2415                             ff_update_duplicate_context(thread_context, s2);
2416                         }
2417                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2418                         s->slice_count++;
2419                     }
2420                     buf_ptr += 2; //FIXME add minimum number of bytes per slice
2421                 }else{
2422                     ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2423                     emms_c();
2424
2425                     if(ret < 0){
2426                         if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2427                             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);
2428                     }else{
2429                         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);
2430                     }
2431                 }
2432             }
2433             break;
2434         }
2435     }
2436 }
2437
2438 static int mpeg_decode_end(AVCodecContext *avctx)
2439 {
2440     Mpeg1Context *s = avctx->priv_data;
2441
2442     if (s->mpeg_enc_ctx_allocated)
2443         MPV_common_end(&s->mpeg_enc_ctx);
2444     return 0;
2445 }
2446
2447 AVCodec mpeg1video_decoder = {
2448     "mpeg1video",
2449     CODEC_TYPE_VIDEO,
2450     CODEC_ID_MPEG1VIDEO,
2451     sizeof(Mpeg1Context),
2452     mpeg_decode_init,
2453     NULL,
2454     mpeg_decode_end,
2455     mpeg_decode_frame,
2456     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2457     .flush= ff_mpeg_flush,
2458     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2459 };
2460
2461 AVCodec mpeg2video_decoder = {
2462     "mpeg2video",
2463     CODEC_TYPE_VIDEO,
2464     CODEC_ID_MPEG2VIDEO,
2465     sizeof(Mpeg1Context),
2466     mpeg_decode_init,
2467     NULL,
2468     mpeg_decode_end,
2469     mpeg_decode_frame,
2470     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2471     .flush= ff_mpeg_flush,
2472     .long_name= NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2473 };
2474
2475 //legacy decoder
2476 AVCodec mpegvideo_decoder = {
2477     "mpegvideo",
2478     CODEC_TYPE_VIDEO,
2479     CODEC_ID_MPEG2VIDEO,
2480     sizeof(Mpeg1Context),
2481     mpeg_decode_init,
2482     NULL,
2483     mpeg_decode_end,
2484     mpeg_decode_frame,
2485     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2486     .flush= ff_mpeg_flush,
2487     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2488 };
2489
2490 #if CONFIG_XVMC
2491 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx){
2492     Mpeg1Context *s;
2493
2494     if( avctx->thread_count > 1)
2495         return -1;
2496     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2497         return -1;
2498     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2499         dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2500     }
2501     mpeg_decode_init(avctx);
2502     s = avctx->priv_data;
2503
2504     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2505     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2506
2507     return 0;
2508 }
2509
2510 AVCodec mpeg_xvmc_decoder = {
2511     "mpegvideo_xvmc",
2512     CODEC_TYPE_VIDEO,
2513     CODEC_ID_MPEG2VIDEO_XVMC,
2514     sizeof(Mpeg1Context),
2515     mpeg_mc_decode_init,
2516     NULL,
2517     mpeg_decode_end,
2518     mpeg_decode_frame,
2519     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2520     .flush= ff_mpeg_flush,
2521     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video XvMC (X-Video Motion Compensation)"),
2522 };
2523
2524 #endif
2525
2526 #if CONFIG_MPEG_VDPAU_DECODER
2527 AVCodec mpeg_vdpau_decoder = {
2528     "mpegvideo_vdpau",
2529     CODEC_TYPE_VIDEO,
2530     CODEC_ID_MPEG2VIDEO,
2531     sizeof(Mpeg1Context),
2532     mpeg_decode_init,
2533     NULL,
2534     mpeg_decode_end,
2535     mpeg_decode_frame,
2536     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2537     .flush= ff_mpeg_flush,
2538     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2539 };
2540 #endif
2541
2542 #if CONFIG_MPEG1_VDPAU_DECODER
2543 AVCodec mpeg1_vdpau_decoder = {
2544     "mpeg1video_vdpau",
2545     CODEC_TYPE_VIDEO,
2546     CODEC_ID_MPEG1VIDEO,
2547     sizeof(Mpeg1Context),
2548     mpeg_decode_init,
2549     NULL,
2550     mpeg_decode_end,
2551     mpeg_decode_frame,
2552     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2553     .flush= ff_mpeg_flush,
2554     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2555 };
2556 #endif
2557