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libavcodec/mpeg12.c

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00001 /*
00002  * MPEG-1/2 decoder
00003  * Copyright (c) 2000,2001 Fabrice Bellard
00004  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00028 //#define DEBUG
00029 #include "internal.h"
00030 #include "avcodec.h"
00031 #include "dsputil.h"
00032 #include "mpegvideo.h"
00033 
00034 #include "mpeg12.h"
00035 #include "mpeg12data.h"
00036 #include "mpeg12decdata.h"
00037 #include "bytestream.h"
00038 #include "vdpau_internal.h"
00039 #include "xvmc_internal.h"
00040 
00041 //#undef NDEBUG
00042 //#include <assert.h>
00043 
00044 
00045 #define MV_VLC_BITS 9
00046 #define MBINCR_VLC_BITS 9
00047 #define MB_PAT_VLC_BITS 9
00048 #define MB_PTYPE_VLC_BITS 6
00049 #define MB_BTYPE_VLC_BITS 6
00050 
00051 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
00052                               DCTELEM *block,
00053                               int n);
00054 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
00055                               DCTELEM *block,
00056                               int n);
00057 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
00058 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
00059                                         DCTELEM *block,
00060                                         int n);
00061 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
00062                                     DCTELEM *block,
00063                                     int n);
00064 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
00065 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
00066 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
00067 static void exchange_uv(MpegEncContext *s);
00068 
00069 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
00070                                            PIX_FMT_XVMC_MPEG2_IDCT,
00071                                            PIX_FMT_XVMC_MPEG2_MC,
00072                                            PIX_FMT_NONE};
00073 
00074 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
00075 
00076 
00077 #define INIT_2D_VLC_RL(rl, static_size)\
00078 {\
00079     static RL_VLC_ELEM rl_vlc_table[static_size];\
00080     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
00081              &rl.table_vlc[0][1], 4, 2,\
00082              &rl.table_vlc[0][0], 4, 2, static_size);\
00083 \
00084     rl.rl_vlc[0]= rl_vlc_table;\
00085     init_2d_vlc_rl(&rl);\
00086 }
00087 
00088 static void init_2d_vlc_rl(RLTable *rl)
00089 {
00090     int i;
00091 
00092     for(i=0; i<rl->vlc.table_size; i++){
00093         int code= rl->vlc.table[i][0];
00094         int len = rl->vlc.table[i][1];
00095         int level, run;
00096 
00097         if(len==0){ // illegal code
00098             run= 65;
00099             level= MAX_LEVEL;
00100         }else if(len<0){ //more bits needed
00101             run= 0;
00102             level= code;
00103         }else{
00104             if(code==rl->n){ //esc
00105                 run= 65;
00106                 level= 0;
00107             }else if(code==rl->n+1){ //eob
00108                 run= 0;
00109                 level= 127;
00110             }else{
00111                 run=   rl->table_run  [code] + 1;
00112                 level= rl->table_level[code];
00113             }
00114         }
00115         rl->rl_vlc[0][i].len= len;
00116         rl->rl_vlc[0][i].level= level;
00117         rl->rl_vlc[0][i].run= run;
00118     }
00119 }
00120 
00121 void ff_mpeg12_common_init(MpegEncContext *s)
00122 {
00123 
00124     s->y_dc_scale_table=
00125     s->c_dc_scale_table= ff_mpeg2_dc_scale_table[s->intra_dc_precision];
00126 
00127 }
00128 
00129 void ff_mpeg1_clean_buffers(MpegEncContext *s){
00130     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
00131     s->last_dc[1] = s->last_dc[0];
00132     s->last_dc[2] = s->last_dc[0];
00133     memset(s->last_mv, 0, sizeof(s->last_mv));
00134 }
00135 
00136 
00137 /******************************************/
00138 /* decoding */
00139 
00140 static VLC mv_vlc;
00141 static VLC mbincr_vlc;
00142 static VLC mb_ptype_vlc;
00143 static VLC mb_btype_vlc;
00144 static VLC mb_pat_vlc;
00145 
00146 av_cold void ff_mpeg12_init_vlcs(void)
00147 {
00148     static int done = 0;
00149 
00150     if (!done) {
00151         done = 1;
00152 
00153         INIT_VLC_STATIC(&dc_lum_vlc, DC_VLC_BITS, 12,
00154                  ff_mpeg12_vlc_dc_lum_bits, 1, 1,
00155                  ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
00156         INIT_VLC_STATIC(&dc_chroma_vlc,  DC_VLC_BITS, 12,
00157                  ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
00158                  ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
00159         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
00160                  &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
00161                  &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
00162         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
00163                  &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
00164                  &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
00165         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
00166                  &ff_mpeg12_mbPatTable[0][1], 2, 1,
00167                  &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
00168 
00169         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
00170                  &table_mb_ptype[0][1], 2, 1,
00171                  &table_mb_ptype[0][0], 2, 1, 64);
00172         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
00173                  &table_mb_btype[0][1], 2, 1,
00174                  &table_mb_btype[0][0], 2, 1, 64);
00175         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
00176         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
00177 
00178         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
00179         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
00180     }
00181 }
00182 
00183 static inline int get_dmv(MpegEncContext *s)
00184 {
00185     if(get_bits1(&s->gb))
00186         return 1 - (get_bits1(&s->gb) << 1);
00187     else
00188         return 0;
00189 }
00190 
00191 static inline int get_qscale(MpegEncContext *s)
00192 {
00193     int qscale = get_bits(&s->gb, 5);
00194     if (s->q_scale_type) {
00195         return non_linear_qscale[qscale];
00196     } else {
00197         return qscale << 1;
00198     }
00199 }
00200 
00201 /* motion type (for MPEG-2) */
00202 #define MT_FIELD 1
00203 #define MT_FRAME 2
00204 #define MT_16X8  2
00205 #define MT_DMV   3
00206 
00207 static int mpeg_decode_mb(MpegEncContext *s,
00208                           DCTELEM block[12][64])
00209 {
00210     int i, j, k, cbp, val, mb_type, motion_type;
00211     const int mb_block_count = 4 + (1<< s->chroma_format);
00212 
00213     dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
00214 
00215     assert(s->mb_skipped==0);
00216 
00217     if (s->mb_skip_run-- != 0) {
00218         if (s->pict_type == FF_P_TYPE) {
00219             s->mb_skipped = 1;
00220             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
00221         } else {
00222             int mb_type;
00223 
00224             if(s->mb_x)
00225                 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
00226             else
00227                 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
00228             if(IS_INTRA(mb_type))
00229                 return -1;
00230 
00231             s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
00232                 mb_type | MB_TYPE_SKIP;
00233 //            assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
00234 
00235             if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
00236                 s->mb_skipped = 1;
00237         }
00238 
00239         return 0;
00240     }
00241 
00242     switch(s->pict_type) {
00243     default:
00244     case FF_I_TYPE:
00245         if (get_bits1(&s->gb) == 0) {
00246             if (get_bits1(&s->gb) == 0){
00247                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
00248                 return -1;
00249             }
00250             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
00251         } else {
00252             mb_type = MB_TYPE_INTRA;
00253         }
00254         break;
00255     case FF_P_TYPE:
00256         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
00257         if (mb_type < 0){
00258             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
00259             return -1;
00260         }
00261         mb_type = ptype2mb_type[ mb_type ];
00262         break;
00263     case FF_B_TYPE:
00264         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
00265         if (mb_type < 0){
00266             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
00267             return -1;
00268         }
00269         mb_type = btype2mb_type[ mb_type ];
00270         break;
00271     }
00272     dprintf(s->avctx, "mb_type=%x\n", mb_type);
00273 //    motion_type = 0; /* avoid warning */
00274     if (IS_INTRA(mb_type)) {
00275         s->dsp.clear_blocks(s->block[0]);
00276 
00277         if(!s->chroma_y_shift){
00278             s->dsp.clear_blocks(s->block[6]);
00279         }
00280 
00281         /* compute DCT type */
00282         if (s->picture_structure == PICT_FRAME && //FIXME add an interlaced_dct coded var?
00283             !s->frame_pred_frame_dct) {
00284             s->interlaced_dct = get_bits1(&s->gb);
00285         }
00286 
00287         if (IS_QUANT(mb_type))
00288             s->qscale = get_qscale(s);
00289 
00290         if (s->concealment_motion_vectors) {
00291             /* just parse them */
00292             if (s->picture_structure != PICT_FRAME)
00293                 skip_bits1(&s->gb); /* field select */
00294 
00295             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
00296                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
00297             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
00298                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
00299 
00300             skip_bits1(&s->gb); /* marker */
00301         }else
00302             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
00303         s->mb_intra = 1;
00304         //if 1, we memcpy blocks in xvmcvideo
00305         if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1){
00306             ff_xvmc_pack_pblocks(s,-1);//inter are always full blocks
00307             if(s->swap_uv){
00308                 exchange_uv(s);
00309             }
00310         }
00311 
00312         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
00313             if(s->flags2 & CODEC_FLAG2_FAST){
00314                 for(i=0;i<6;i++) {
00315                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
00316                 }
00317             }else{
00318                 for(i=0;i<mb_block_count;i++) {
00319                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
00320                         return -1;
00321                 }
00322             }
00323         } else {
00324             for(i=0;i<6;i++) {
00325                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
00326                     return -1;
00327             }
00328         }
00329     } else {
00330         if (mb_type & MB_TYPE_ZERO_MV){
00331             assert(mb_type & MB_TYPE_CBP);
00332 
00333             s->mv_dir = MV_DIR_FORWARD;
00334             if(s->picture_structure == PICT_FRAME){
00335                 if(!s->frame_pred_frame_dct)
00336                     s->interlaced_dct = get_bits1(&s->gb);
00337                 s->mv_type = MV_TYPE_16X16;
00338             }else{
00339                 s->mv_type = MV_TYPE_FIELD;
00340                 mb_type |= MB_TYPE_INTERLACED;
00341                 s->field_select[0][0]= s->picture_structure - 1;
00342             }
00343 
00344             if (IS_QUANT(mb_type))
00345                 s->qscale = get_qscale(s);
00346 
00347             s->last_mv[0][0][0] = 0;
00348             s->last_mv[0][0][1] = 0;
00349             s->last_mv[0][1][0] = 0;
00350             s->last_mv[0][1][1] = 0;
00351             s->mv[0][0][0] = 0;
00352             s->mv[0][0][1] = 0;
00353         }else{
00354             assert(mb_type & MB_TYPE_L0L1);
00355 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
00356             /* get additional motion vector type */
00357             if (s->frame_pred_frame_dct)
00358                 motion_type = MT_FRAME;
00359             else{
00360                 motion_type = get_bits(&s->gb, 2);
00361                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
00362                     s->interlaced_dct = get_bits1(&s->gb);
00363             }
00364 
00365             if (IS_QUANT(mb_type))
00366                 s->qscale = get_qscale(s);
00367 
00368             /* motion vectors */
00369             s->mv_dir= (mb_type>>13)&3;
00370             dprintf(s->avctx, "motion_type=%d\n", motion_type);
00371             switch(motion_type) {
00372             case MT_FRAME: /* or MT_16X8 */
00373                 if (s->picture_structure == PICT_FRAME) {
00374                     mb_type |= MB_TYPE_16x16;
00375                     s->mv_type = MV_TYPE_16X16;
00376                     for(i=0;i<2;i++) {
00377                         if (USES_LIST(mb_type, i)) {
00378                             /* MT_FRAME */
00379                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
00380                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
00381                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
00382                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
00383                             /* full_pel: only for MPEG-1 */
00384                             if (s->full_pel[i]){
00385                                 s->mv[i][0][0] <<= 1;
00386                                 s->mv[i][0][1] <<= 1;
00387                             }
00388                         }
00389                     }
00390                 } else {
00391                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
00392                     s->mv_type = MV_TYPE_16X8;
00393                     for(i=0;i<2;i++) {
00394                         if (USES_LIST(mb_type, i)) {
00395                             /* MT_16X8 */
00396                             for(j=0;j<2;j++) {
00397                                 s->field_select[i][j] = get_bits1(&s->gb);
00398                                 for(k=0;k<2;k++) {
00399                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
00400                                                              s->last_mv[i][j][k]);
00401                                     s->last_mv[i][j][k] = val;
00402                                     s->mv[i][j][k] = val;
00403                                 }
00404                             }
00405                         }
00406                     }
00407                 }
00408                 break;
00409             case MT_FIELD:
00410                 s->mv_type = MV_TYPE_FIELD;
00411                 if (s->picture_structure == PICT_FRAME) {
00412                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
00413                     for(i=0;i<2;i++) {
00414                         if (USES_LIST(mb_type, i)) {
00415                             for(j=0;j<2;j++) {
00416                                 s->field_select[i][j] = get_bits1(&s->gb);
00417                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
00418                                                          s->last_mv[i][j][0]);
00419                                 s->last_mv[i][j][0] = val;
00420                                 s->mv[i][j][0] = val;
00421                                 dprintf(s->avctx, "fmx=%d\n", val);
00422                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
00423                                                          s->last_mv[i][j][1] >> 1);
00424                                 s->last_mv[i][j][1] = val << 1;
00425                                 s->mv[i][j][1] = val;
00426                                 dprintf(s->avctx, "fmy=%d\n", val);
00427                             }
00428                         }
00429                     }
00430                 } else {
00431                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
00432                     for(i=0;i<2;i++) {
00433                         if (USES_LIST(mb_type, i)) {
00434                             s->field_select[i][0] = get_bits1(&s->gb);
00435                             for(k=0;k<2;k++) {
00436                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
00437                                                          s->last_mv[i][0][k]);
00438                                 s->last_mv[i][0][k] = val;
00439                                 s->last_mv[i][1][k] = val;
00440                                 s->mv[i][0][k] = val;
00441                             }
00442                         }
00443                     }
00444                 }
00445                 break;
00446             case MT_DMV:
00447                 s->mv_type = MV_TYPE_DMV;
00448                 for(i=0;i<2;i++) {
00449                     if (USES_LIST(mb_type, i)) {
00450                         int dmx, dmy, mx, my, m;
00451                         const int my_shift= s->picture_structure == PICT_FRAME;
00452 
00453                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
00454                                                 s->last_mv[i][0][0]);
00455                         s->last_mv[i][0][0] = mx;
00456                         s->last_mv[i][1][0] = mx;
00457                         dmx = get_dmv(s);
00458                         my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
00459                                                 s->last_mv[i][0][1] >> my_shift);
00460                         dmy = get_dmv(s);
00461 
00462 
00463                         s->last_mv[i][0][1] = my<<my_shift;
00464                         s->last_mv[i][1][1] = my<<my_shift;
00465 
00466                         s->mv[i][0][0] = mx;
00467                         s->mv[i][0][1] = my;
00468                         s->mv[i][1][0] = mx;//not used
00469                         s->mv[i][1][1] = my;//not used
00470 
00471                         if (s->picture_structure == PICT_FRAME) {
00472                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
00473 
00474                             //m = 1 + 2 * s->top_field_first;
00475                             m = s->top_field_first ? 1 : 3;
00476 
00477                             /* top -> top pred */
00478                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
00479                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
00480                             m = 4 - m;
00481                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
00482                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
00483                         } else {
00484                             mb_type |= MB_TYPE_16x16;
00485 
00486                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
00487                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
00488                             if(s->picture_structure == PICT_TOP_FIELD)
00489                                 s->mv[i][2][1]--;
00490                             else
00491                                 s->mv[i][2][1]++;
00492                         }
00493                     }
00494                 }
00495                 break;
00496             default:
00497                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
00498                 return -1;
00499             }
00500         }
00501 
00502         s->mb_intra = 0;
00503         if (HAS_CBP(mb_type)) {
00504             s->dsp.clear_blocks(s->block[0]);
00505 
00506             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
00507             if(mb_block_count > 6){
00508                  cbp<<= mb_block_count-6;
00509                  cbp |= get_bits(&s->gb, mb_block_count-6);
00510                  s->dsp.clear_blocks(s->block[6]);
00511             }
00512             if (cbp <= 0){
00513                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
00514                 return -1;
00515             }
00516 
00517             //if 1, we memcpy blocks in xvmcvideo
00518             if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1){
00519                 ff_xvmc_pack_pblocks(s,cbp);
00520                 if(s->swap_uv){
00521                     exchange_uv(s);
00522                 }
00523             }
00524 
00525             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
00526                 if(s->flags2 & CODEC_FLAG2_FAST){
00527                     for(i=0;i<6;i++) {
00528                         if(cbp & 32) {
00529                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
00530                         } else {
00531                             s->block_last_index[i] = -1;
00532                         }
00533                         cbp+=cbp;
00534                     }
00535                 }else{
00536                     cbp<<= 12-mb_block_count;
00537 
00538                     for(i=0;i<mb_block_count;i++) {
00539                         if ( cbp & (1<<11) ) {
00540                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
00541                                 return -1;
00542                         } else {
00543                             s->block_last_index[i] = -1;
00544                         }
00545                         cbp+=cbp;
00546                     }
00547                 }
00548             } else {
00549                 if(s->flags2 & CODEC_FLAG2_FAST){
00550                     for(i=0;i<6;i++) {
00551                         if (cbp & 32) {
00552                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
00553                         } else {
00554                             s->block_last_index[i] = -1;
00555                         }
00556                         cbp+=cbp;
00557                     }
00558                 }else{
00559                     for(i=0;i<6;i++) {
00560                         if (cbp & 32) {
00561                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
00562                                 return -1;
00563                         } else {
00564                             s->block_last_index[i] = -1;
00565                         }
00566                         cbp+=cbp;
00567                     }
00568                 }
00569             }
00570         }else{
00571             for(i=0;i<12;i++)
00572                 s->block_last_index[i] = -1;
00573         }
00574     }
00575 
00576     s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
00577 
00578     return 0;
00579 }
00580 
00581 /* as H.263, but only 17 codes */
00582 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
00583 {
00584     int code, sign, val, l, shift;
00585 
00586     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
00587     if (code == 0) {
00588         return pred;
00589     }
00590     if (code < 0) {
00591         return 0xffff;
00592     }
00593 
00594     sign = get_bits1(&s->gb);
00595     shift = fcode - 1;
00596     val = code;
00597     if (shift) {
00598         val = (val - 1) << shift;
00599         val |= get_bits(&s->gb, shift);
00600         val++;
00601     }
00602     if (sign)
00603         val = -val;
00604     val += pred;
00605 
00606     /* modulo decoding */
00607     l= INT_BIT - 5 - shift;
00608     val = (val<<l)>>l;
00609     return val;
00610 }
00611 
00612 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
00613                                DCTELEM *block,
00614                                int n)
00615 {
00616     int level, dc, diff, i, j, run;
00617     int component;
00618     RLTable *rl = &ff_rl_mpeg1;
00619     uint8_t * const scantable= s->intra_scantable.permutated;
00620     const uint16_t *quant_matrix= s->intra_matrix;
00621     const int qscale= s->qscale;
00622 
00623     /* DC coefficient */
00624     component = (n <= 3 ? 0 : n - 4 + 1);
00625     diff = decode_dc(&s->gb, component);
00626     if (diff >= 0xffff)
00627         return -1;
00628     dc = s->last_dc[component];
00629     dc += diff;
00630     s->last_dc[component] = dc;
00631     block[0] = dc*quant_matrix[0];
00632     dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
00633     i = 0;
00634     {
00635         OPEN_READER(re, &s->gb);
00636         /* now quantify & encode AC coefficients */
00637         for(;;) {
00638             UPDATE_CACHE(re, &s->gb);
00639             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00640 
00641             if(level == 127){
00642                 break;
00643             } else if(level != 0) {
00644                 i += run;
00645                 j = scantable[i];
00646                 level= (level*qscale*quant_matrix[j])>>4;
00647                 level= (level-1)|1;
00648                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00649                 LAST_SKIP_BITS(re, &s->gb, 1);
00650             } else {
00651                 /* escape */
00652                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00653                 UPDATE_CACHE(re, &s->gb);
00654                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00655                 if (level == -128) {
00656                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
00657                 } else if (level == 0) {
00658                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
00659                 }
00660                 i += run;
00661                 j = scantable[i];
00662                 if(level<0){
00663                     level= -level;
00664                     level= (level*qscale*quant_matrix[j])>>4;
00665                     level= (level-1)|1;
00666                     level= -level;
00667                 }else{
00668                     level= (level*qscale*quant_matrix[j])>>4;
00669                     level= (level-1)|1;
00670                 }
00671             }
00672             if (i > 63){
00673                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00674                 return -1;
00675             }
00676 
00677             block[j] = level;
00678         }
00679         CLOSE_READER(re, &s->gb);
00680     }
00681     s->block_last_index[n] = i;
00682    return 0;
00683 }
00684 
00685 int ff_mpeg1_decode_block_intra(MpegEncContext *s,
00686                                 DCTELEM *block,
00687                                 int n)
00688 {
00689     return mpeg1_decode_block_intra(s, block, n);
00690 }
00691 
00692 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
00693                                DCTELEM *block,
00694                                int n)
00695 {
00696     int level, i, j, run;
00697     RLTable *rl = &ff_rl_mpeg1;
00698     uint8_t * const scantable= s->intra_scantable.permutated;
00699     const uint16_t *quant_matrix= s->inter_matrix;
00700     const int qscale= s->qscale;
00701 
00702     {
00703         OPEN_READER(re, &s->gb);
00704         i = -1;
00705         // special case for first coefficient, no need to add second VLC table
00706         UPDATE_CACHE(re, &s->gb);
00707         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00708             level= (3*qscale*quant_matrix[0])>>5;
00709             level= (level-1)|1;
00710             if(GET_CACHE(re, &s->gb)&0x40000000)
00711                 level= -level;
00712             block[0] = level;
00713             i++;
00714             SKIP_BITS(re, &s->gb, 2);
00715             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00716                 goto end;
00717         }
00718 #if MIN_CACHE_BITS < 19
00719         UPDATE_CACHE(re, &s->gb);
00720 #endif
00721         /* now quantify & encode AC coefficients */
00722         for(;;) {
00723             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00724 
00725             if(level != 0) {
00726                 i += run;
00727                 j = scantable[i];
00728                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
00729                 level= (level-1)|1;
00730                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00731                 SKIP_BITS(re, &s->gb, 1);
00732             } else {
00733                 /* escape */
00734                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00735                 UPDATE_CACHE(re, &s->gb);
00736                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00737                 if (level == -128) {
00738                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
00739                 } else if (level == 0) {
00740                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
00741                 }
00742                 i += run;
00743                 j = scantable[i];
00744                 if(level<0){
00745                     level= -level;
00746                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
00747                     level= (level-1)|1;
00748                     level= -level;
00749                 }else{
00750                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
00751                     level= (level-1)|1;
00752                 }
00753             }
00754             if (i > 63){
00755                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00756                 return -1;
00757             }
00758 
00759             block[j] = level;
00760 #if MIN_CACHE_BITS < 19
00761             UPDATE_CACHE(re, &s->gb);
00762 #endif
00763             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00764                 break;
00765 #if MIN_CACHE_BITS >= 19
00766             UPDATE_CACHE(re, &s->gb);
00767 #endif
00768         }
00769 end:
00770         LAST_SKIP_BITS(re, &s->gb, 2);
00771         CLOSE_READER(re, &s->gb);
00772     }
00773     s->block_last_index[n] = i;
00774     return 0;
00775 }
00776 
00777 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
00778 {
00779     int level, i, j, run;
00780     RLTable *rl = &ff_rl_mpeg1;
00781     uint8_t * const scantable= s->intra_scantable.permutated;
00782     const int qscale= s->qscale;
00783 
00784     {
00785         OPEN_READER(re, &s->gb);
00786         i = -1;
00787         // special case for first coefficient, no need to add second VLC table
00788         UPDATE_CACHE(re, &s->gb);
00789         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00790             level= (3*qscale)>>1;
00791             level= (level-1)|1;
00792             if(GET_CACHE(re, &s->gb)&0x40000000)
00793                 level= -level;
00794             block[0] = level;
00795             i++;
00796             SKIP_BITS(re, &s->gb, 2);
00797             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00798                 goto end;
00799         }
00800 #if MIN_CACHE_BITS < 19
00801         UPDATE_CACHE(re, &s->gb);
00802 #endif
00803 
00804         /* now quantify & encode AC coefficients */
00805         for(;;) {
00806             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00807 
00808             if(level != 0) {
00809                 i += run;
00810                 j = scantable[i];
00811                 level= ((level*2+1)*qscale)>>1;
00812                 level= (level-1)|1;
00813                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00814                 SKIP_BITS(re, &s->gb, 1);
00815             } else {
00816                 /* escape */
00817                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00818                 UPDATE_CACHE(re, &s->gb);
00819                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00820                 if (level == -128) {
00821                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
00822                 } else if (level == 0) {
00823                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
00824                 }
00825                 i += run;
00826                 j = scantable[i];
00827                 if(level<0){
00828                     level= -level;
00829                     level= ((level*2+1)*qscale)>>1;
00830                     level= (level-1)|1;
00831                     level= -level;
00832                 }else{
00833                     level= ((level*2+1)*qscale)>>1;
00834                     level= (level-1)|1;
00835                 }
00836             }
00837 
00838             block[j] = level;
00839 #if MIN_CACHE_BITS < 19
00840             UPDATE_CACHE(re, &s->gb);
00841 #endif
00842             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00843                 break;
00844 #if MIN_CACHE_BITS >= 19
00845             UPDATE_CACHE(re, &s->gb);
00846 #endif
00847         }
00848 end:
00849         LAST_SKIP_BITS(re, &s->gb, 2);
00850         CLOSE_READER(re, &s->gb);
00851     }
00852     s->block_last_index[n] = i;
00853     return 0;
00854 }
00855 
00856 
00857 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
00858                                DCTELEM *block,
00859                                int n)
00860 {
00861     int level, i, j, run;
00862     RLTable *rl = &ff_rl_mpeg1;
00863     uint8_t * const scantable= s->intra_scantable.permutated;
00864     const uint16_t *quant_matrix;
00865     const int qscale= s->qscale;
00866     int mismatch;
00867 
00868     mismatch = 1;
00869 
00870     {
00871         OPEN_READER(re, &s->gb);
00872         i = -1;
00873         if (n < 4)
00874             quant_matrix = s->inter_matrix;
00875         else
00876             quant_matrix = s->chroma_inter_matrix;
00877 
00878         // special case for first coefficient, no need to add second VLC table
00879         UPDATE_CACHE(re, &s->gb);
00880         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00881             level= (3*qscale*quant_matrix[0])>>5;
00882             if(GET_CACHE(re, &s->gb)&0x40000000)
00883                 level= -level;
00884             block[0] = level;
00885             mismatch ^= level;
00886             i++;
00887             SKIP_BITS(re, &s->gb, 2);
00888             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00889                 goto end;
00890         }
00891 #if MIN_CACHE_BITS < 19
00892         UPDATE_CACHE(re, &s->gb);
00893 #endif
00894 
00895         /* now quantify & encode AC coefficients */
00896         for(;;) {
00897             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00898 
00899             if(level != 0) {
00900                 i += run;
00901                 j = scantable[i];
00902                 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
00903                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00904                 SKIP_BITS(re, &s->gb, 1);
00905             } else {
00906                 /* escape */
00907                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00908                 UPDATE_CACHE(re, &s->gb);
00909                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00910 
00911                 i += run;
00912                 j = scantable[i];
00913                 if(level<0){
00914                     level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
00915                     level= -level;
00916                 }else{
00917                     level= ((level*2+1)*qscale*quant_matrix[j])>>5;
00918                 }
00919             }
00920             if (i > 63){
00921                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00922                 return -1;
00923             }
00924 
00925             mismatch ^= level;
00926             block[j] = level;
00927 #if MIN_CACHE_BITS < 19
00928             UPDATE_CACHE(re, &s->gb);
00929 #endif
00930             if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00931                 break;
00932 #if MIN_CACHE_BITS >= 19
00933             UPDATE_CACHE(re, &s->gb);
00934 #endif
00935         }
00936 end:
00937         LAST_SKIP_BITS(re, &s->gb, 2);
00938         CLOSE_READER(re, &s->gb);
00939     }
00940     block[63] ^= (mismatch & 1);
00941 
00942     s->block_last_index[n] = i;
00943     return 0;
00944 }
00945 
00946 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
00947                                DCTELEM *block,
00948                                int n)
00949 {
00950     int level, i, j, run;
00951     RLTable *rl = &ff_rl_mpeg1;
00952     uint8_t * const scantable= s->intra_scantable.permutated;
00953     const int qscale= s->qscale;
00954     OPEN_READER(re, &s->gb);
00955     i = -1;
00956 
00957     // special case for first coefficient, no need to add second VLC table
00958     UPDATE_CACHE(re, &s->gb);
00959     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00960         level= (3*qscale)>>1;
00961         if(GET_CACHE(re, &s->gb)&0x40000000)
00962             level= -level;
00963         block[0] = level;
00964         i++;
00965         SKIP_BITS(re, &s->gb, 2);
00966         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00967             goto end;
00968     }
00969 #if MIN_CACHE_BITS < 19
00970     UPDATE_CACHE(re, &s->gb);
00971 #endif
00972 
00973     /* now quantify & encode AC coefficients */
00974     for(;;) {
00975         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00976 
00977         if(level != 0) {
00978             i += run;
00979             j = scantable[i];
00980             level= ((level*2+1)*qscale)>>1;
00981             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00982             SKIP_BITS(re, &s->gb, 1);
00983         } else {
00984             /* escape */
00985             run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00986             UPDATE_CACHE(re, &s->gb);
00987             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00988 
00989             i += run;
00990             j = scantable[i];
00991             if(level<0){
00992                 level= ((-level*2+1)*qscale)>>1;
00993                 level= -level;
00994             }else{
00995                 level= ((level*2+1)*qscale)>>1;
00996             }
00997         }
00998 
00999         block[j] = level;
01000 #if MIN_CACHE_BITS < 19
01001         UPDATE_CACHE(re, &s->gb);
01002 #endif
01003         if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
01004             break;
01005 #if MIN_CACHE_BITS >=19
01006         UPDATE_CACHE(re, &s->gb);
01007 #endif
01008     }
01009 end:
01010     LAST_SKIP_BITS(re, &s->gb, 2);
01011     CLOSE_READER(re, &s->gb);
01012     s->block_last_index[n] = i;
01013     return 0;
01014 }
01015 
01016 
01017 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
01018                                DCTELEM *block,
01019                                int n)
01020 {
01021     int level, dc, diff, i, j, run;
01022     int component;
01023     RLTable *rl;
01024     uint8_t * const scantable= s->intra_scantable.permutated;
01025     const uint16_t *quant_matrix;
01026     const int qscale= s->qscale;
01027     int mismatch;
01028 
01029     /* DC coefficient */
01030     if (n < 4){
01031         quant_matrix = s->intra_matrix;
01032         component = 0;
01033     }else{
01034         quant_matrix = s->chroma_intra_matrix;
01035         component = (n&1) + 1;
01036     }
01037     diff = decode_dc(&s->gb, component);
01038     if (diff >= 0xffff)
01039         return -1;
01040     dc = s->last_dc[component];
01041     dc += diff;
01042     s->last_dc[component] = dc;
01043     block[0] = dc << (3 - s->intra_dc_precision);
01044     dprintf(s->avctx, "dc=%d\n", block[0]);
01045     mismatch = block[0] ^ 1;
01046     i = 0;
01047     if (s->intra_vlc_format)
01048         rl = &ff_rl_mpeg2;
01049     else
01050         rl = &ff_rl_mpeg1;
01051 
01052     {
01053         OPEN_READER(re, &s->gb);
01054         /* now quantify & encode AC coefficients */
01055         for(;;) {
01056             UPDATE_CACHE(re, &s->gb);
01057             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
01058 
01059             if(level == 127){
01060                 break;
01061             } else if(level != 0) {
01062                 i += run;
01063                 j = scantable[i];
01064                 level= (level*qscale*quant_matrix[j])>>4;
01065                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01066                 LAST_SKIP_BITS(re, &s->gb, 1);
01067             } else {
01068                 /* escape */
01069                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
01070                 UPDATE_CACHE(re, &s->gb);
01071                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
01072                 i += run;
01073                 j = scantable[i];
01074                 if(level<0){
01075                     level= (-level*qscale*quant_matrix[j])>>4;
01076                     level= -level;
01077                 }else{
01078                     level= (level*qscale*quant_matrix[j])>>4;
01079                 }
01080             }
01081             if (i > 63){
01082                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
01083                 return -1;
01084             }
01085 
01086             mismatch^= level;
01087             block[j] = level;
01088         }
01089         CLOSE_READER(re, &s->gb);
01090     }
01091     block[63]^= mismatch&1;
01092 
01093     s->block_last_index[n] = i;
01094     return 0;
01095 }
01096 
01097 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
01098                                DCTELEM *block,
01099                                int n)
01100 {
01101     int level, dc, diff, j, run;
01102     int component;
01103     RLTable *rl;
01104     uint8_t * scantable= s->intra_scantable.permutated;
01105     const uint16_t *quant_matrix;
01106     const int qscale= s->qscale;
01107 
01108     /* DC coefficient */
01109     if (n < 4){
01110         quant_matrix = s->intra_matrix;
01111         component = 0;
01112     }else{
01113         quant_matrix = s->chroma_intra_matrix;
01114         component = (n&1) + 1;
01115     }
01116     diff = decode_dc(&s->gb, component);
01117     if (diff >= 0xffff)
01118         return -1;
01119     dc = s->last_dc[component];
01120     dc += diff;
01121     s->last_dc[component] = dc;
01122     block[0] = dc << (3 - s->intra_dc_precision);
01123     if (s->intra_vlc_format)
01124         rl = &ff_rl_mpeg2;
01125     else
01126         rl = &ff_rl_mpeg1;
01127 
01128     {
01129         OPEN_READER(re, &s->gb);
01130         /* now quantify & encode AC coefficients */
01131         for(;;) {
01132             UPDATE_CACHE(re, &s->gb);
01133             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
01134 
01135             if(level == 127){
01136                 break;
01137             } else if(level != 0) {
01138                 scantable += run;
01139                 j = *scantable;
01140                 level= (level*qscale*quant_matrix[j])>>4;
01141                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
01142                 LAST_SKIP_BITS(re, &s->gb, 1);
01143             } else {
01144                 /* escape */
01145                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
01146                 UPDATE_CACHE(re, &s->gb);
01147                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
01148                 scantable += run;
01149                 j = *scantable;
01150                 if(level<0){
01151                     level= (-level*qscale*quant_matrix[j])>>4;
01152                     level= -level;
01153                 }else{
01154                     level= (level*qscale*quant_matrix[j])>>4;
01155                 }
01156             }
01157 
01158             block[j] = level;
01159         }
01160         CLOSE_READER(re, &s->gb);
01161     }
01162 
01163     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
01164     return 0;
01165 }
01166 
01167 typedef struct Mpeg1Context {
01168     MpegEncContext mpeg_enc_ctx;
01169     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
01170     int repeat_field; /* true if we must repeat the field */
01171     AVPanScan pan_scan; 
01172     int slice_count;
01173     int swap_uv;//indicate VCR2
01174     int save_aspect_info;
01175     int save_width, save_height, save_progressive_seq;
01176     AVRational frame_rate_ext;       
01177     int sync;                        
01178 } Mpeg1Context;
01179 
01180 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
01181 {
01182     Mpeg1Context *s = avctx->priv_data;
01183     MpegEncContext *s2 = &s->mpeg_enc_ctx;
01184     int i;
01185 
01186     /* we need some permutation to store matrices,
01187      * until MPV_common_init() sets the real permutation. */
01188     for(i=0;i<64;i++)
01189        s2->dsp.idct_permutation[i]=i;
01190 
01191     MPV_decode_defaults(s2);
01192 
01193     s->mpeg_enc_ctx.avctx= avctx;
01194     s->mpeg_enc_ctx.flags= avctx->flags;
01195     s->mpeg_enc_ctx.flags2= avctx->flags2;
01196     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
01197     ff_mpeg12_init_vlcs();
01198 
01199     s->mpeg_enc_ctx_allocated = 0;
01200     s->mpeg_enc_ctx.picture_number = 0;
01201     s->repeat_field = 0;
01202     s->mpeg_enc_ctx.codec_id= avctx->codec->id;
01203     avctx->color_range= AVCOL_RANGE_MPEG;
01204     if (avctx->codec->id == CODEC_ID_MPEG1VIDEO)
01205         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
01206     else
01207         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
01208     return 0;
01209 }
01210 
01211 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
01212                                      const uint8_t *new_perm){
01213     uint16_t temp_matrix[64];
01214     int i;
01215 
01216     memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
01217 
01218     for(i=0;i<64;i++){
01219         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
01220     }
01221 }
01222 
01223 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx){
01224     Mpeg1Context *s1 = avctx->priv_data;
01225     MpegEncContext *s = &s1->mpeg_enc_ctx;
01226 
01227     if(avctx->xvmc_acceleration)
01228         return avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
01229     else if(avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU){
01230         if(avctx->codec_id == CODEC_ID_MPEG1VIDEO)
01231             return PIX_FMT_VDPAU_MPEG1;
01232         else
01233             return PIX_FMT_VDPAU_MPEG2;
01234     }else{
01235         if(s->chroma_format <  2)
01236             return avctx->get_format(avctx,ff_hwaccel_pixfmt_list_420);
01237         else if(s->chroma_format == 2)
01238             return PIX_FMT_YUV422P;
01239         else
01240             return PIX_FMT_YUV444P;
01241     }
01242 }
01243 
01244 /* Call this function when we know all parameters.
01245  * It may be called in different places for MPEG-1 and MPEG-2. */
01246 static int mpeg_decode_postinit(AVCodecContext *avctx){
01247     Mpeg1Context *s1 = avctx->priv_data;
01248     MpegEncContext *s = &s1->mpeg_enc_ctx;
01249     uint8_t old_permutation[64];
01250 
01251     if (
01252         (s1->mpeg_enc_ctx_allocated == 0)||
01253         avctx->coded_width  != s->width ||
01254         avctx->coded_height != s->height||
01255         s1->save_width != s->width ||
01256         s1->save_height != s->height ||
01257         s1->save_aspect_info != s->aspect_ratio_info||
01258         s1->save_progressive_seq != s->progressive_sequence ||
01259         0)
01260     {
01261 
01262         if (s1->mpeg_enc_ctx_allocated) {
01263             ParseContext pc= s->parse_context;
01264             s->parse_context.buffer=0;
01265             MPV_common_end(s);
01266             s->parse_context= pc;
01267         }
01268 
01269         if( (s->width == 0 )||(s->height == 0))
01270             return -2;
01271 
01272         avcodec_set_dimensions(avctx, s->width, s->height);
01273         avctx->bit_rate = s->bit_rate;
01274         s1->save_aspect_info = s->aspect_ratio_info;
01275         s1->save_width = s->width;
01276         s1->save_height = s->height;
01277         s1->save_progressive_seq = s->progressive_sequence;
01278 
01279         /* low_delay may be forced, in this case we will have B-frames
01280          * that behave like P-frames. */
01281         avctx->has_b_frames = !(s->low_delay);
01282 
01283         assert((avctx->sub_id==1) == (avctx->codec_id==CODEC_ID_MPEG1VIDEO));
01284         if(avctx->codec_id==CODEC_ID_MPEG1VIDEO){
01285             //MPEG-1 fps
01286             avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
01287             avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
01288             //MPEG-1 aspect
01289             avctx->sample_aspect_ratio= av_d2q(
01290                     1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
01291             avctx->ticks_per_frame=1;
01292         }else{//MPEG-2
01293         //MPEG-2 fps
01294             av_reduce(
01295                 &s->avctx->time_base.den,
01296                 &s->avctx->time_base.num,
01297                 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
01298                 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
01299                 1<<30);
01300             avctx->ticks_per_frame=2;
01301         //MPEG-2 aspect
01302             if(s->aspect_ratio_info > 1){
01303                 //we ignore the spec here as reality does not match the spec, see for example
01304                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
01305                 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) || 1){
01306                     s->avctx->sample_aspect_ratio=
01307                         av_div_q(
01308                          ff_mpeg2_aspect[s->aspect_ratio_info],
01309                          (AVRational){s->width, s->height}
01310                          );
01311                 }else{
01312                     s->avctx->sample_aspect_ratio=
01313                         av_div_q(
01314                          ff_mpeg2_aspect[s->aspect_ratio_info],
01315                          (AVRational){s1->pan_scan.width, s1->pan_scan.height}
01316                         );
01317                 }
01318             }else{
01319                 s->avctx->sample_aspect_ratio=
01320                     ff_mpeg2_aspect[s->aspect_ratio_info];
01321             }
01322         }//MPEG-2
01323 
01324         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
01325         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
01326         //until then pix_fmt may be changed right after codec init
01327         if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
01328             avctx->hwaccel ||
01329             s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
01330             if( avctx->idct_algo == FF_IDCT_AUTO )
01331                 avctx->idct_algo = FF_IDCT_SIMPLE;
01332 
01333         /* Quantization matrices may need reordering
01334          * if DCT permutation is changed. */
01335         memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
01336 
01337         if (MPV_common_init(s) < 0)
01338             return -2;
01339 
01340         quant_matrix_rebuild(s->intra_matrix,       old_permutation,s->dsp.idct_permutation);
01341         quant_matrix_rebuild(s->inter_matrix,       old_permutation,s->dsp.idct_permutation);
01342         quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
01343         quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
01344 
01345         s1->mpeg_enc_ctx_allocated = 1;
01346     }
01347     return 0;
01348 }
01349 
01350 static int mpeg1_decode_picture(AVCodecContext *avctx,
01351                                 const uint8_t *buf, int buf_size)
01352 {
01353     Mpeg1Context *s1 = avctx->priv_data;
01354     MpegEncContext *s = &s1->mpeg_enc_ctx;
01355     int ref, f_code, vbv_delay;
01356 
01357     init_get_bits(&s->gb, buf, buf_size*8);
01358 
01359     ref = get_bits(&s->gb, 10); /* temporal ref */
01360     s->pict_type = get_bits(&s->gb, 3);
01361     if(s->pict_type == 0 || s->pict_type > 3)
01362         return -1;
01363 
01364     vbv_delay= get_bits(&s->gb, 16);
01365     if (s->pict_type == FF_P_TYPE || s->pict_type == FF_B_TYPE) {
01366         s->full_pel[0] = get_bits1(&s->gb);
01367         f_code = get_bits(&s->gb, 3);
01368         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
01369             return -1;
01370         s->mpeg_f_code[0][0] = f_code;
01371         s->mpeg_f_code[0][1] = f_code;
01372     }
01373     if (s->pict_type == FF_B_TYPE) {
01374         s->full_pel[1] = get_bits1(&s->gb);
01375         f_code = get_bits(&s->gb, 3);
01376         if (f_code == 0 && avctx->error_recognition >= FF_ER_COMPLIANT)
01377             return -1;
01378         s->mpeg_f_code[1][0] = f_code;
01379         s->mpeg_f_code[1][1] = f_code;
01380     }
01381     s->current_picture.pict_type= s->pict_type;
01382     s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
01383 
01384     if(avctx->debug & FF_DEBUG_PICT_INFO)
01385         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
01386 
01387     s->y_dc_scale = 8;
01388     s->c_dc_scale = 8;
01389     return 0;
01390 }
01391 
01392 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
01393 {
01394     MpegEncContext *s= &s1->mpeg_enc_ctx;
01395     int horiz_size_ext, vert_size_ext;
01396     int bit_rate_ext;
01397 
01398     skip_bits(&s->gb, 1); /* profile and level esc*/
01399     s->avctx->profile= get_bits(&s->gb, 3);
01400     s->avctx->level= get_bits(&s->gb, 4);
01401     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
01402     s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
01403     horiz_size_ext = get_bits(&s->gb, 2);
01404     vert_size_ext = get_bits(&s->gb, 2);
01405     s->width |= (horiz_size_ext << 12);
01406     s->height |= (vert_size_ext << 12);
01407     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
01408     s->bit_rate += (bit_rate_ext << 18) * 400;
01409     skip_bits1(&s->gb); /* marker */
01410     s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
01411 
01412     s->low_delay = get_bits1(&s->gb);
01413     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
01414 
01415     s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
01416     s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
01417 
01418     dprintf(s->avctx, "sequence extension\n");
01419     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
01420     s->avctx->sub_id = 2; /* indicates MPEG-2 found */
01421 
01422     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
01423         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
01424                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
01425 
01426 }
01427 
01428 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
01429 {
01430     MpegEncContext *s= &s1->mpeg_enc_ctx;
01431     int color_description, w, h;
01432 
01433     skip_bits(&s->gb, 3); /* video format */
01434     color_description= get_bits1(&s->gb);
01435     if(color_description){
01436         s->avctx->color_primaries= get_bits(&s->gb, 8);
01437         s->avctx->color_trc      = get_bits(&s->gb, 8);
01438         s->avctx->colorspace     = get_bits(&s->gb, 8);
01439     }
01440     w= get_bits(&s->gb, 14);
01441     skip_bits(&s->gb, 1); //marker
01442     h= get_bits(&s->gb, 14);
01443     skip_bits(&s->gb, 1); //marker
01444 
01445     s1->pan_scan.width= 16*w;
01446     s1->pan_scan.height=16*h;
01447 
01448     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
01449         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
01450 }
01451 
01452 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
01453 {
01454     MpegEncContext *s= &s1->mpeg_enc_ctx;
01455     int i,nofco;
01456 
01457     nofco = 1;
01458     if(s->progressive_sequence){
01459         if(s->repeat_first_field){
01460             nofco++;
01461             if(s->top_field_first)
01462                 nofco++;
01463         }
01464     }else{
01465         if(s->picture_structure == PICT_FRAME){
01466             nofco++;
01467             if(s->repeat_first_field)
01468                 nofco++;
01469         }
01470     }
01471     for(i=0; i<nofco; i++){
01472         s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
01473         skip_bits(&s->gb, 1); //marker
01474         s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
01475         skip_bits(&s->gb, 1); //marker
01476     }
01477 
01478     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
01479         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
01480             s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
01481             s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
01482             s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
01483         );
01484 }
01485 
01486 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra){
01487     int i;
01488 
01489     for(i=0; i<64; i++) {
01490         int j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
01491         int v = get_bits(&s->gb, 8);
01492         if(v==0){
01493             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
01494             return -1;
01495         }
01496         if(intra && i==0 && v!=8){
01497             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
01498             v= 8; // needed by pink.mpg / issue1046
01499         }
01500         matrix0[j] = v;
01501         if(matrix1)
01502             matrix1[j] = v;
01503     }
01504     return 0;
01505 }
01506 
01507 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
01508 {
01509     dprintf(s->avctx, "matrix extension\n");
01510 
01511     if(get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
01512     if(get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
01513     if(get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
01514     if(get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
01515 }
01516 
01517 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
01518 {
01519     MpegEncContext *s= &s1->mpeg_enc_ctx;
01520 
01521     s->full_pel[0] = s->full_pel[1] = 0;
01522     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
01523     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
01524     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
01525     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
01526     if(!s->pict_type && s1->mpeg_enc_ctx_allocated){
01527         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
01528         if(s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1]==15){
01529             if(s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
01530                 s->pict_type= FF_I_TYPE;
01531             else
01532                 s->pict_type= FF_P_TYPE;
01533         }else
01534             s->pict_type= FF_B_TYPE;
01535         s->current_picture.pict_type= s->pict_type;
01536         s->current_picture.key_frame= s->pict_type == FF_I_TYPE;
01537     }
01538     s->intra_dc_precision = get_bits(&s->gb, 2);
01539     s->picture_structure = get_bits(&s->gb, 2);
01540     s->top_field_first = get_bits1(&s->gb);
01541     s->frame_pred_frame_dct = get_bits1(&s->gb);
01542     s->concealment_motion_vectors = get_bits1(&s->gb);
01543     s->q_scale_type = get_bits1(&s->gb);
01544     s->intra_vlc_format = get_bits1(&s->gb);
01545     s->alternate_scan = get_bits1(&s->gb);
01546     s->repeat_first_field = get_bits1(&s->gb);
01547     s->chroma_420_type = get_bits1(&s->gb);
01548     s->progressive_frame = get_bits1(&s->gb);
01549 
01550     if(s->progressive_sequence && !s->progressive_frame){
01551         s->progressive_frame= 1;
01552         av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
01553     }
01554 
01555     if(s->picture_structure==0 || (s->progressive_frame && s->picture_structure!=PICT_FRAME)){
01556         av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
01557         s->picture_structure= PICT_FRAME;
01558     }
01559 
01560     if(s->progressive_sequence && !s->frame_pred_frame_dct){
01561         av_log(s->avctx, AV_LOG_ERROR, "invalid frame_pred_frame_dct\n");
01562         s->frame_pred_frame_dct= 1;
01563     }
01564 
01565     if(s->picture_structure == PICT_FRAME){
01566         s->first_field=0;
01567         s->v_edge_pos= 16*s->mb_height;
01568     }else{
01569         s->first_field ^= 1;
01570         s->v_edge_pos=  8*s->mb_height;
01571         memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
01572     }
01573 
01574     if(s->alternate_scan){
01575         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_alternate_vertical_scan);
01576         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_alternate_vertical_scan);
01577     }else{
01578         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable  , ff_zigzag_direct);
01579         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable  , ff_zigzag_direct);
01580     }
01581 
01582     /* composite display not parsed */
01583     dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
01584     dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
01585     dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
01586     dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
01587     dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
01588     dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
01589     dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
01590     dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
01591     dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
01592 }
01593 
01594 static void exchange_uv(MpegEncContext *s){
01595     DCTELEM (*tmp)[64];
01596 
01597     tmp           = s->pblocks[4];
01598     s->pblocks[4] = s->pblocks[5];
01599     s->pblocks[5] = tmp;
01600 }
01601 
01602 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size){
01603     AVCodecContext *avctx= s->avctx;
01604     Mpeg1Context *s1 = (Mpeg1Context*)s;
01605 
01606     /* start frame decoding */
01607     if(s->first_field || s->picture_structure==PICT_FRAME){
01608         if(MPV_frame_start(s, avctx) < 0)
01609             return -1;
01610 
01611         ff_er_frame_start(s);
01612 
01613         /* first check if we must repeat the frame */
01614         s->current_picture_ptr->repeat_pict = 0;
01615         if (s->repeat_first_field) {
01616             if (s->progressive_sequence) {
01617                 if (s->top_field_first)
01618                     s->current_picture_ptr->repeat_pict = 4;
01619                 else
01620                     s->current_picture_ptr->repeat_pict = 2;
01621             } else if (s->progressive_frame) {
01622                 s->current_picture_ptr->repeat_pict = 1;
01623             }
01624         }
01625 
01626         *s->current_picture_ptr->pan_scan= s1->pan_scan;
01627     }else{ //second field
01628             int i;
01629 
01630             if(!s->current_picture_ptr){
01631                 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
01632                 return -1;
01633             }
01634 
01635             for(i=0; i<4; i++){
01636                 s->current_picture.data[i] = s->current_picture_ptr->data[i];
01637                 if(s->picture_structure == PICT_BOTTOM_FIELD){
01638                     s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
01639                 }
01640             }
01641     }
01642 
01643     if (avctx->hwaccel) {
01644         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
01645             return -1;
01646     }
01647 
01648 // MPV_frame_start will call this function too,
01649 // but we need to call it on every field
01650     if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
01651         if(ff_xvmc_field_start(s,avctx) < 0)
01652             return -1;
01653 
01654     return 0;
01655 }
01656 
01657 #define DECODE_SLICE_ERROR -1
01658 #define DECODE_SLICE_OK 0
01659 
01665 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
01666                              const uint8_t **buf, int buf_size)
01667 {
01668     MpegEncContext *s = &s1->mpeg_enc_ctx;
01669     AVCodecContext *avctx= s->avctx;
01670     const int field_pic= s->picture_structure != PICT_FRAME;
01671     const int lowres= s->avctx->lowres;
01672 
01673     s->resync_mb_x=
01674     s->resync_mb_y= -1;
01675 
01676     assert(mb_y < s->mb_height);
01677 
01678     init_get_bits(&s->gb, *buf, buf_size*8);
01679 
01680     ff_mpeg1_clean_buffers(s);
01681     s->interlaced_dct = 0;
01682 
01683     s->qscale = get_qscale(s);
01684 
01685     if(s->qscale == 0){
01686         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
01687         return -1;
01688     }
01689 
01690     /* extra slice info */
01691     while (get_bits1(&s->gb) != 0) {
01692         skip_bits(&s->gb, 8);
01693     }
01694 
01695     s->mb_x=0;
01696 
01697     if(mb_y==0 && s->codec_tag == AV_RL32("SLIF")){
01698         skip_bits1(&s->gb);
01699     }else{
01700         for(;;) {
01701             int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
01702             if (code < 0){
01703                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
01704                 return -1;
01705             }
01706             if (code >= 33) {
01707                 if (code == 33) {
01708                     s->mb_x += 33;
01709                 }
01710                 /* otherwise, stuffing, nothing to do */
01711             } else {
01712                 s->mb_x += code;
01713                 break;
01714             }
01715         }
01716     }
01717 
01718     if(s->mb_x >= (unsigned)s->mb_width){
01719         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
01720         return -1;
01721     }
01722 
01723     if (avctx->hwaccel) {
01724         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
01725         int start_code = -1;
01726         buf_end = ff_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
01727         if (buf_end < *buf + buf_size)
01728             buf_end -= 4;
01729         s->mb_y = mb_y;
01730         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
01731             return DECODE_SLICE_ERROR;
01732         *buf = buf_end;
01733         return DECODE_SLICE_OK;
01734     }
01735 
01736     s->resync_mb_x= s->mb_x;
01737     s->resync_mb_y= s->mb_y= mb_y;
01738     s->mb_skip_run= 0;
01739     ff_init_block_index(s);
01740 
01741     if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
01742         if(s->avctx->debug&FF_DEBUG_PICT_INFO){
01743              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",
01744                  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],
01745                  s->pict_type == FF_I_TYPE ? "I" : (s->pict_type == FF_P_TYPE ? "P" : (s->pict_type == FF_B_TYPE ? "B" : "S")),
01746                  s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
01747                  s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
01748                  s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
01749         }
01750     }
01751 
01752     for(;;) {
01753         //If 1, we memcpy blocks in xvmcvideo.
01754         if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
01755             ff_xvmc_init_block(s);//set s->block
01756 
01757         if(mpeg_decode_mb(s, s->block) < 0)
01758             return -1;
01759 
01760         if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
01761             const int wrap = s->b8_stride;
01762             int xy = s->mb_x*2 + s->mb_y*2*wrap;
01763             int b8_xy= 4*(s->mb_x + s->mb_y*s->mb_stride);
01764             int motion_x, motion_y, dir, i;
01765 
01766             for(i=0; i<2; i++){
01767                 for(dir=0; dir<2; dir++){
01768                     if (s->mb_intra || (dir==1 && s->pict_type != FF_B_TYPE)) {
01769                         motion_x = motion_y = 0;
01770                     }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
01771                         motion_x = s->mv[dir][0][0];
01772                         motion_y = s->mv[dir][0][1];
01773                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
01774                         motion_x = s->mv[dir][i][0];
01775                         motion_y = s->mv[dir][i][1];
01776                     }
01777 
01778                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
01779                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
01780                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
01781                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
01782                     s->current_picture.ref_index [dir][b8_xy    ]=
01783                     s->current_picture.ref_index [dir][b8_xy + 1]= s->field_select[dir][i];
01784                     assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
01785                 }
01786                 xy += wrap;
01787                 b8_xy +=2;
01788             }
01789         }
01790 
01791         s->dest[0] += 16 >> lowres;
01792         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
01793         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
01794 
01795         MPV_decode_mb(s, s->block);
01796 
01797         if (++s->mb_x >= s->mb_width) {
01798             const int mb_size= 16>>s->avctx->lowres;
01799 
01800             ff_draw_horiz_band(s, mb_size*(s->mb_y>>field_pic), mb_size);
01801 
01802             s->mb_x = 0;
01803             s->mb_y += 1<<field_pic;
01804 
01805             if(s->mb_y >= s->mb_height){
01806                 int left= get_bits_left(&s->gb);
01807                 int is_d10= s->chroma_format==2 && s->pict_type==FF_I_TYPE && avctx->profile==0 && avctx->level==5
01808                             && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
01809                             && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
01810 
01811                 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
01812                    || (avctx->error_recognition >= FF_ER_AGGRESSIVE && left>8)){
01813                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
01814                     return -1;
01815                 }else
01816                     goto eos;
01817             }
01818 
01819             ff_init_block_index(s);
01820         }
01821 
01822         /* skip mb handling */
01823         if (s->mb_skip_run == -1) {
01824             /* read increment again */
01825             s->mb_skip_run = 0;
01826             for(;;) {
01827                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
01828                 if (code < 0){
01829                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
01830                     return -1;
01831                 }
01832                 if (code >= 33) {
01833                     if (code == 33) {
01834                         s->mb_skip_run += 33;
01835                     }else if(code == 35){
01836                         if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
01837                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
01838                             return -1;
01839                         }
01840                         goto eos; /* end of slice */
01841                     }
01842                     /* otherwise, stuffing, nothing to do */
01843                 } else {
01844                     s->mb_skip_run += code;
01845                     break;
01846                 }
01847             }
01848             if(s->mb_skip_run){
01849                 int i;
01850                 if(s->pict_type == FF_I_TYPE){
01851                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
01852                     return -1;
01853                 }
01854 
01855                 /* skip mb */
01856                 s->mb_intra = 0;
01857                 for(i=0;i<12;i++)
01858                     s->block_last_index[i] = -1;
01859                 if(s->picture_structure == PICT_FRAME)
01860                     s->mv_type = MV_TYPE_16X16;
01861                 else
01862                     s->mv_type = MV_TYPE_FIELD;
01863                 if (s->pict_type == FF_P_TYPE) {
01864                     /* if P type, zero motion vector is implied */
01865                     s->mv_dir = MV_DIR_FORWARD;
01866                     s->mv[0][0][0] = s->mv[0][0][1] = 0;
01867                     s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
01868                     s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
01869                     s->field_select[0][0]= (s->picture_structure - 1) & 1;
01870                 } else {
01871                     /* if B type, reuse previous vectors and directions */
01872                     s->mv[0][0][0] = s->last_mv[0][0][0];
01873                     s->mv[0][0][1] = s->last_mv[0][0][1];
01874                     s->mv[1][0][0] = s->last_mv[1][0][0];
01875                     s->mv[1][0][1] = s->last_mv[1][0][1];
01876                 }
01877             }
01878         }
01879     }
01880 eos: // end of slice
01881     *buf += (get_bits_count(&s->gb)-1)/8;
01882 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
01883     return 0;
01884 }
01885 
01886 static int slice_decode_thread(AVCodecContext *c, void *arg){
01887     MpegEncContext *s= *(void**)arg;
01888     const uint8_t *buf= s->gb.buffer;
01889     int mb_y= s->start_mb_y;
01890     const int field_pic= s->picture_structure != PICT_FRAME;
01891 
01892     s->error_count= (3*(s->end_mb_y - s->start_mb_y)*s->mb_width) >> field_pic;
01893 
01894     for(;;){
01895         uint32_t start_code;
01896         int ret;
01897 
01898         ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
01899         emms_c();
01900 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
01901 //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);
01902         if(ret < 0){
01903             if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
01904                 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);
01905         }else{
01906             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);
01907         }
01908 
01909         if(s->mb_y == s->end_mb_y)
01910             return 0;
01911 
01912         start_code= -1;
01913         buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
01914         mb_y= start_code - SLICE_MIN_START_CODE;
01915         if(mb_y < 0 || mb_y >= s->end_mb_y)
01916             return -1;
01917     }
01918 
01919     return 0; //not reached
01920 }
01921 
01926 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
01927 {
01928     Mpeg1Context *s1 = avctx->priv_data;
01929     MpegEncContext *s = &s1->mpeg_enc_ctx;
01930 
01931     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
01932         return 0;
01933 
01934     if (s->avctx->hwaccel) {
01935         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
01936             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
01937     }
01938 
01939     if(CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
01940         ff_xvmc_field_end(s);
01941 
01942     /* end of slice reached */
01943     if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
01944         /* end of image */
01945 
01946         s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
01947 
01948         ff_er_frame_end(s);
01949 
01950         MPV_frame_end(s);
01951 
01952         if (s->pict_type == FF_B_TYPE || s->low_delay) {
01953             *pict= *(AVFrame*)s->current_picture_ptr;
01954             ff_print_debug_info(s, pict);
01955         } else {
01956             s->picture_number++;
01957             /* latency of 1 frame for I- and P-frames */
01958             /* XXX: use another variable than picture_number */
01959             if (s->last_picture_ptr != NULL) {
01960                 *pict= *(AVFrame*)s->last_picture_ptr;
01961                  ff_print_debug_info(s, pict);
01962             }
01963         }
01964 
01965         return 1;
01966     } else {
01967         return 0;
01968     }
01969 }
01970 
01971 static int mpeg1_decode_sequence(AVCodecContext *avctx,
01972                                  const uint8_t *buf, int buf_size)
01973 {
01974     Mpeg1Context *s1 = avctx->priv_data;
01975     MpegEncContext *s = &s1->mpeg_enc_ctx;
01976     int width,height;
01977     int i, v, j;
01978 
01979     init_get_bits(&s->gb, buf, buf_size*8);
01980 
01981     width = get_bits(&s->gb, 12);
01982     height = get_bits(&s->gb, 12);
01983     if (width <= 0 || height <= 0)
01984         return -1;
01985     s->aspect_ratio_info= get_bits(&s->gb, 4);
01986     if (s->aspect_ratio_info == 0) {
01987         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
01988         if (avctx->error_recognition >= FF_ER_COMPLIANT)
01989             return -1;
01990     }
01991     s->frame_rate_index = get_bits(&s->gb, 4);
01992     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
01993         return -1;
01994     s->bit_rate = get_bits(&s->gb, 18) * 400;
01995     if (get_bits1(&s->gb) == 0) /* marker */
01996         return -1;
01997     s->width = width;
01998     s->height = height;
01999 
02000     s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
02001     skip_bits(&s->gb, 1);
02002 
02003     /* get matrix */
02004     if (get_bits1(&s->gb)) {
02005         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
02006     } else {
02007         for(i=0;i<64;i++) {
02008             j = s->dsp.idct_permutation[i];
02009             v = ff_mpeg1_default_intra_matrix[i];
02010             s->intra_matrix[j] = v;
02011             s->chroma_intra_matrix[j] = v;
02012         }
02013     }
02014     if (get_bits1(&s->gb)) {
02015         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
02016     } else {
02017         for(i=0;i<64;i++) {
02018             int j= s->dsp.idct_permutation[i];
02019             v = ff_mpeg1_default_non_intra_matrix[i];
02020             s->inter_matrix[j] = v;
02021             s->chroma_inter_matrix[j] = v;
02022         }
02023     }
02024 
02025     if(show_bits(&s->gb, 23) != 0){
02026         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
02027         return -1;
02028     }
02029 
02030     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
02031     s->progressive_sequence = 1;
02032     s->progressive_frame = 1;
02033     s->picture_structure = PICT_FRAME;
02034     s->frame_pred_frame_dct = 1;
02035     s->chroma_format = 1;
02036     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
02037     avctx->sub_id = 1; /* indicates MPEG-1 */
02038     s->out_format = FMT_MPEG1;
02039     s->swap_uv = 0;//AFAIK VCR2 does not have SEQ_HEADER
02040     if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
02041 
02042     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
02043         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
02044                s->avctx->rc_buffer_size, s->bit_rate);
02045 
02046     return 0;
02047 }
02048 
02049 static int vcr2_init_sequence(AVCodecContext *avctx)
02050 {
02051     Mpeg1Context *s1 = avctx->priv_data;
02052     MpegEncContext *s = &s1->mpeg_enc_ctx;
02053     int i, v;
02054 
02055     /* start new MPEG-1 context decoding */
02056     s->out_format = FMT_MPEG1;
02057     if (s1->mpeg_enc_ctx_allocated) {
02058         MPV_common_end(s);
02059     }
02060     s->width  = avctx->coded_width;
02061     s->height = avctx->coded_height;
02062     avctx->has_b_frames= 0; //true?
02063     s->low_delay= 1;
02064 
02065     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
02066     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
02067 
02068     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
02069         s->avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU )
02070         if( avctx->idct_algo == FF_IDCT_AUTO )
02071             avctx->idct_algo = FF_IDCT_SIMPLE;
02072 
02073     if (MPV_common_init(s) < 0)
02074         return -1;
02075     exchange_uv(s);//common init reset pblocks, so we swap them here
02076     s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
02077     s1->mpeg_enc_ctx_allocated = 1;
02078 
02079     for(i=0;i<64;i++) {
02080         int j= s->dsp.idct_permutation[i];
02081         v = ff_mpeg1_default_intra_matrix[i];
02082         s->intra_matrix[j] = v;
02083         s->chroma_intra_matrix[j] = v;
02084 
02085         v = ff_mpeg1_default_non_intra_matrix[i];
02086         s->inter_matrix[j] = v;
02087         s->chroma_inter_matrix[j] = v;
02088     }
02089 
02090     s->progressive_sequence = 1;
02091     s->progressive_frame = 1;
02092     s->picture_structure = PICT_FRAME;
02093     s->frame_pred_frame_dct = 1;
02094     s->chroma_format = 1;
02095     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
02096     avctx->sub_id = 2; /* indicates MPEG-2 */
02097     s1->save_width           = s->width;
02098     s1->save_height          = s->height;
02099     s1->save_progressive_seq = s->progressive_sequence;
02100     return 0;
02101 }
02102 
02103 
02104 static void mpeg_decode_user_data(AVCodecContext *avctx,
02105                                   const uint8_t *p, int buf_size)
02106 {
02107     const uint8_t *buf_end = p+buf_size;
02108 
02109     /* we parse the DTG active format information */
02110     if (buf_end - p >= 5 &&
02111         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
02112         int flags = p[4];
02113         p += 5;
02114         if (flags & 0x80) {
02115             /* skip event id */
02116             p += 2;
02117         }
02118         if (flags & 0x40) {
02119             if (buf_end - p < 1)
02120                 return;
02121             avctx->dtg_active_format = p[0] & 0x0f;
02122         }
02123     }
02124 }
02125 
02126 static void mpeg_decode_gop(AVCodecContext *avctx,
02127                             const uint8_t *buf, int buf_size){
02128     Mpeg1Context *s1 = avctx->priv_data;
02129     MpegEncContext *s = &s1->mpeg_enc_ctx;
02130 
02131     int drop_frame_flag;
02132     int time_code_hours, time_code_minutes;
02133     int time_code_seconds, time_code_pictures;
02134     int broken_link;
02135 
02136     init_get_bits(&s->gb, buf, buf_size*8);
02137 
02138     drop_frame_flag = get_bits1(&s->gb);
02139 
02140     time_code_hours=get_bits(&s->gb,5);
02141     time_code_minutes = get_bits(&s->gb,6);
02142     skip_bits1(&s->gb);//marker bit
02143     time_code_seconds = get_bits(&s->gb,6);
02144     time_code_pictures = get_bits(&s->gb,6);
02145 
02146     s->closed_gop = get_bits1(&s->gb);
02147     /*broken_link indicate that after editing the
02148       reference frames of the first B-Frames after GOP I-Frame
02149       are missing (open gop)*/
02150     broken_link = get_bits1(&s->gb);
02151 
02152     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
02153         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
02154             time_code_hours, time_code_minutes, time_code_seconds,
02155             time_code_pictures, s->closed_gop, broken_link);
02156 }
02161 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
02162 {
02163     int i;
02164     uint32_t state= pc->state;
02165 
02166     /* EOF considered as end of frame */
02167     if (buf_size == 0)
02168         return 0;
02169 
02170 /*
02171  0  frame start         -> 1/4
02172  1  first_SEQEXT        -> 0/2
02173  2  first field start   -> 3/0
02174  3  second_SEQEXT       -> 2/0
02175  4  searching end
02176 */
02177 
02178     for(i=0; i<buf_size; i++){
02179         assert(pc->frame_start_found>=0 && pc->frame_start_found<=4);
02180         if(pc->frame_start_found&1){
02181             if(state == EXT_START_CODE && (buf[i]&0xF0) != 0x80)
02182                 pc->frame_start_found--;
02183             else if(state == EXT_START_CODE+2){
02184                 if((buf[i]&3) == 3) pc->frame_start_found= 0;
02185                 else                pc->frame_start_found= (pc->frame_start_found+1)&3;
02186             }
02187             state++;
02188         }else{
02189             i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
02190             if(pc->frame_start_found==0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
02191                 i++;
02192                 pc->frame_start_found=4;
02193             }
02194             if(state == SEQ_END_CODE){
02195                 pc->state=-1;
02196                 return i+1;
02197             }
02198             if(pc->frame_start_found==2 && state == SEQ_START_CODE)
02199                 pc->frame_start_found= 0;
02200             if(pc->frame_start_found<4 && state == EXT_START_CODE)
02201                 pc->frame_start_found++;
02202             if(pc->frame_start_found == 4 && (state&0xFFFFFF00) == 0x100){
02203                 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
02204                     pc->frame_start_found=0;
02205                     pc->state=-1;
02206                     return i-3;
02207                 }
02208             }
02209             if(pc->frame_start_found == 0 && s && state == PICTURE_START_CODE){
02210                 ff_fetch_timestamp(s, i-3, 1);
02211             }
02212         }
02213     }
02214     pc->state= state;
02215     return END_NOT_FOUND;
02216 }
02217 
02218 static int decode_chunks(AVCodecContext *avctx,
02219                              AVFrame *picture, int *data_size,
02220                              const uint8_t *buf, int buf_size);
02221 
02222 /* handle buffering and image synchronisation */
02223 static int mpeg_decode_frame(AVCodecContext *avctx,
02224                              void *data, int *data_size,
02225                              AVPacket *avpkt)
02226 {
02227     const uint8_t *buf = avpkt->data;
02228     int buf_size = avpkt->size;
02229     Mpeg1Context *s = avctx->priv_data;
02230     AVFrame *picture = data;
02231     MpegEncContext *s2 = &s->mpeg_enc_ctx;
02232     dprintf(avctx, "fill_buffer\n");
02233 
02234     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
02235         /* special case for last picture */
02236         if (s2->low_delay==0 && s2->next_picture_ptr) {
02237             *picture= *(AVFrame*)s2->next_picture_ptr;
02238             s2->next_picture_ptr= NULL;
02239 
02240             *data_size = sizeof(AVFrame);
02241         }
02242         return buf_size;
02243     }
02244 
02245     if(s2->flags&CODEC_FLAG_TRUNCATED){
02246         int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
02247 
02248         if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
02249             return buf_size;
02250     }
02251 
02252 #if 0
02253     if (s->repeat_field % 2 == 1) {
02254         s->repeat_field++;
02255         //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
02256         //        s2->picture_number, s->repeat_field);
02257         if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
02258             *data_size = sizeof(AVPicture);
02259             goto the_end;
02260         }
02261     }
02262 #endif
02263 
02264     if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == AV_RL32("VCR2"))
02265         vcr2_init_sequence(avctx);
02266 
02267     s->slice_count= 0;
02268 
02269     if(avctx->extradata && !avctx->frame_number)
02270         decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
02271 
02272     return decode_chunks(avctx, picture, data_size, buf, buf_size);
02273 }
02274 
02275 static int decode_chunks(AVCodecContext *avctx,
02276                              AVFrame *picture, int *data_size,
02277                              const uint8_t *buf, int buf_size)
02278 {
02279     Mpeg1Context *s = avctx->priv_data;
02280     MpegEncContext *s2 = &s->mpeg_enc_ctx;
02281     const uint8_t *buf_ptr = buf;
02282     const uint8_t *buf_end = buf + buf_size;
02283     int ret, input_size;
02284     int last_code= 0;
02285 
02286     for(;;) {
02287         /* find next start code */
02288         uint32_t start_code = -1;
02289         buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
02290         if (start_code > 0x1ff){
02291             if(s2->pict_type != FF_B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
02292                 if(avctx->thread_count > 1){
02293                     int i;
02294 
02295                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
02296                     for(i=0; i<s->slice_count; i++)
02297                         s2->error_count += s2->thread_context[i]->error_count;
02298                 }
02299 
02300                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU)
02301                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
02302 
02303                 if (slice_end(avctx, picture)) {
02304                     if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
02305                         *data_size = sizeof(AVPicture);
02306                 }
02307             }
02308             s2->pict_type= 0;
02309             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
02310         }
02311 
02312         input_size = buf_end - buf_ptr;
02313 
02314         if(avctx->debug & FF_DEBUG_STARTCODE){
02315             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
02316         }
02317 
02318         /* prepare data for next start code */
02319         switch(start_code) {
02320         case SEQ_START_CODE:
02321             if(last_code == 0){
02322             mpeg1_decode_sequence(avctx, buf_ptr,
02323                                     input_size);
02324                 s->sync=1;
02325             }else{
02326                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
02327             }
02328             break;
02329 
02330         case PICTURE_START_CODE:
02331             if(last_code == 0 || last_code == SLICE_MIN_START_CODE){
02332             if(mpeg_decode_postinit(avctx) < 0){
02333                 av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
02334                 return -1;
02335             }
02336 
02337             /* we have a complete image: we try to decompress it */
02338             if(mpeg1_decode_picture(avctx,
02339                                     buf_ptr, input_size) < 0)
02340                 s2->pict_type=0;
02341                 s2->first_slice = 1;
02342             last_code= PICTURE_START_CODE;
02343             }else{
02344                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
02345             }
02346             break;
02347         case EXT_START_CODE:
02348             init_get_bits(&s2->gb, buf_ptr, input_size*8);
02349 
02350             switch(get_bits(&s2->gb, 4)) {
02351             case 0x1:
02352                 if(last_code == 0){
02353                 mpeg_decode_sequence_extension(s);
02354                 }else{
02355                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
02356                 }
02357                 break;
02358             case 0x2:
02359                 mpeg_decode_sequence_display_extension(s);
02360                 break;
02361             case 0x3:
02362                 mpeg_decode_quant_matrix_extension(s2);
02363                 break;
02364             case 0x7:
02365                 mpeg_decode_picture_display_extension(s);
02366                 break;
02367             case 0x8:
02368                 if(last_code == PICTURE_START_CODE){
02369                 mpeg_decode_picture_coding_extension(s);
02370                 }else{
02371                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
02372                 }
02373                 break;
02374             }
02375             break;
02376         case USER_START_CODE:
02377             mpeg_decode_user_data(avctx,
02378                                     buf_ptr, input_size);
02379             break;
02380         case GOP_START_CODE:
02381             if(last_code == 0){
02382             s2->first_field=0;
02383             mpeg_decode_gop(avctx,
02384                                     buf_ptr, input_size);
02385                 s->sync=1;
02386             }else{
02387                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
02388             }
02389             break;
02390         default:
02391             if (start_code >= SLICE_MIN_START_CODE &&
02392                 start_code <= SLICE_MAX_START_CODE && last_code!=0) {
02393                 const int field_pic= s2->picture_structure != PICT_FRAME;
02394                 int mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
02395                 last_code= SLICE_MIN_START_CODE;
02396 
02397                 if(s2->picture_structure == PICT_BOTTOM_FIELD)
02398                     mb_y++;
02399 
02400                 if (mb_y >= s2->mb_height){
02401                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
02402                     return -1;
02403                 }
02404 
02405                 if(s2->last_picture_ptr==NULL){
02406                 /* Skip B-frames if we do not have reference frames and gop is not closed */
02407                     if(s2->pict_type==FF_B_TYPE){
02408                         if(!s2->closed_gop)
02409                             break;
02410                     }
02411                 }
02412                 if(s2->pict_type==FF_I_TYPE)
02413                     s->sync=1;
02414                 if(s2->next_picture_ptr==NULL){
02415                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
02416                     if(s2->pict_type==FF_P_TYPE && !s->sync) break;
02417                 }
02418                 /* Skip B-frames if we are in a hurry. */
02419                 if(avctx->hurry_up && s2->pict_type==FF_B_TYPE) break;
02420                 if(  (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==FF_B_TYPE)
02421                     ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=FF_I_TYPE)
02422                     || avctx->skip_frame >= AVDISCARD_ALL)
02423                     break;
02424                 /* Skip everything if we are in a hurry>=5. */
02425                 if(avctx->hurry_up>=5) break;
02426 
02427                 if (!s->mpeg_enc_ctx_allocated) break;
02428 
02429                 if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
02430                     if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
02431                         break;
02432                 }
02433 
02434                 if(!s2->pict_type){
02435                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
02436                     break;
02437                 }
02438 
02439                 if(s2->first_slice){
02440                     s2->first_slice=0;
02441                     if(mpeg_field_start(s2, buf, buf_size) < 0)
02442                         return -1;
02443                 }
02444                 if(!s2->current_picture_ptr){
02445                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
02446                     return -1;
02447                 }
02448 
02449                 if (avctx->codec->capabilities&CODEC_CAP_HWACCEL_VDPAU) {
02450                     s->slice_count++;
02451                     break;
02452                 }
02453 
02454                 if(avctx->thread_count > 1){
02455                     int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
02456                     if(threshold <= mb_y){
02457                         MpegEncContext *thread_context= s2->thread_context[s->slice_count];
02458 
02459                         thread_context->start_mb_y= mb_y;
02460                         thread_context->end_mb_y  = s2->mb_height;
02461                         if(s->slice_count){
02462                             s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
02463                             ff_update_duplicate_context(thread_context, s2);
02464                         }
02465                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
02466                         s->slice_count++;
02467                     }
02468                     buf_ptr += 2; //FIXME add minimum number of bytes per slice
02469                 }else{
02470                     ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
02471                     emms_c();
02472 
02473                     if(ret < 0){
02474                         if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
02475                             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);
02476                     }else{
02477                         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);
02478                     }
02479                 }
02480             }
02481             break;
02482         }
02483     }
02484 }
02485 
02486 static void flush(AVCodecContext *avctx){
02487     Mpeg1Context *s = avctx->priv_data;
02488 
02489     s->sync=0;
02490 
02491     ff_mpeg_flush(avctx);
02492 }
02493 
02494 static int mpeg_decode_end(AVCodecContext *avctx)
02495 {
02496     Mpeg1Context *s = avctx->priv_data;
02497 
02498     if (s->mpeg_enc_ctx_allocated)
02499         MPV_common_end(&s->mpeg_enc_ctx);
02500     return 0;
02501 }
02502 
02503 AVCodec mpeg1video_decoder = {
02504     "mpeg1video",
02505     AVMEDIA_TYPE_VIDEO,
02506     CODEC_ID_MPEG1VIDEO,
02507     sizeof(Mpeg1Context),
02508     mpeg_decode_init,
02509     NULL,
02510     mpeg_decode_end,
02511     mpeg_decode_frame,
02512     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
02513     .flush= flush,
02514     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
02515 };
02516 
02517 AVCodec mpeg2video_decoder = {
02518     "mpeg2video",
02519     AVMEDIA_TYPE_VIDEO,
02520     CODEC_ID_MPEG2VIDEO,
02521     sizeof(Mpeg1Context),
02522     mpeg_decode_init,
02523     NULL,
02524     mpeg_decode_end,
02525     mpeg_decode_frame,
02526     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
02527     .flush= flush,
02528     .long_name= NULL_IF_CONFIG_SMALL("MPEG-2 video"),
02529 };
02530 
02531 //legacy decoder
02532 AVCodec mpegvideo_decoder = {
02533     "mpegvideo",
02534     AVMEDIA_TYPE_VIDEO,
02535     CODEC_ID_MPEG2VIDEO,
02536     sizeof(Mpeg1Context),
02537     mpeg_decode_init,
02538     NULL,
02539     mpeg_decode_end,
02540     mpeg_decode_frame,
02541     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
02542     .flush= flush,
02543     .long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
02544 };
02545 
02546 #if CONFIG_MPEG_XVMC_DECODER
02547 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx){
02548     if( avctx->thread_count > 1)
02549         return -1;
02550     if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
02551         return -1;
02552     if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
02553         dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
02554     }
02555     mpeg_decode_init(avctx);
02556 
02557     avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
02558     avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
02559 
02560     return 0;
02561 }
02562 
02563 AVCodec mpeg_xvmc_decoder = {
02564     "mpegvideo_xvmc",
02565     AVMEDIA_TYPE_VIDEO,
02566     CODEC_ID_MPEG2VIDEO_XVMC,
02567     sizeof(Mpeg1Context),
02568     mpeg_mc_decode_init,
02569     NULL,
02570     mpeg_decode_end,
02571     mpeg_decode_frame,
02572     CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
02573     .flush= flush,
02574     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
02575 };
02576 
02577 #endif
02578 
02579 #if CONFIG_MPEG_VDPAU_DECODER
02580 AVCodec mpeg_vdpau_decoder = {
02581     "mpegvideo_vdpau",
02582     AVMEDIA_TYPE_VIDEO,
02583     CODEC_ID_MPEG2VIDEO,
02584     sizeof(Mpeg1Context),
02585     mpeg_decode_init,
02586     NULL,
02587     mpeg_decode_end,
02588     mpeg_decode_frame,
02589     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
02590     .flush= flush,
02591     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
02592 };
02593 #endif
02594 
02595 #if CONFIG_MPEG1_VDPAU_DECODER
02596 AVCodec mpeg1_vdpau_decoder = {
02597     "mpeg1video_vdpau",
02598     AVMEDIA_TYPE_VIDEO,
02599     CODEC_ID_MPEG1VIDEO,
02600     sizeof(Mpeg1Context),
02601     mpeg_decode_init,
02602     NULL,
02603     mpeg_decode_end,
02604     mpeg_decode_frame,
02605     CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
02606     .flush= flush,
02607     .long_name = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
02608 };
02609 #endif
02610 

Generated on Fri Sep 16 2011 17:17:39 for FFmpeg by  doxygen 1.7.1