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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 Libav.
00007  *
00008  * Libav 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  * Libav 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 Libav; 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 #include "thread.h"
00041 
00042 //#undef NDEBUG
00043 //#include <assert.h>
00044 
00045 
00046 #define MV_VLC_BITS 9
00047 #define MBINCR_VLC_BITS 9
00048 #define MB_PAT_VLC_BITS 9
00049 #define MB_PTYPE_VLC_BITS 6
00050 #define MB_BTYPE_VLC_BITS 6
00051 
00052 static VLC mv_vlc;
00053 
00054 /* as H.263, but only 17 codes */
00055 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
00056 {
00057     int code, sign, val, shift;
00058 
00059     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
00060     if (code == 0) {
00061         return pred;
00062     }
00063     if (code < 0) {
00064         return 0xffff;
00065     }
00066 
00067     sign  = get_bits1(&s->gb);
00068     shift = fcode - 1;
00069     val   = code;
00070     if (shift) {
00071         val  = (val - 1) << shift;
00072         val |= get_bits(&s->gb, shift);
00073         val++;
00074     }
00075     if (sign)
00076         val = -val;
00077     val += pred;
00078 
00079     /* modulo decoding */
00080     return sign_extend(val, 5 + shift);
00081 }
00082 
00083 static inline int mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00084 {
00085     int level, dc, diff, i, j, run;
00086     int component;
00087     RLTable *rl = &ff_rl_mpeg1;
00088     uint8_t * const scantable    = s->intra_scantable.permutated;
00089     const uint16_t *quant_matrix = s->intra_matrix;
00090     const int qscale             = s->qscale;
00091 
00092     /* DC coefficient */
00093     component = (n <= 3 ? 0 : n - 4 + 1);
00094     diff = decode_dc(&s->gb, component);
00095     if (diff >= 0xffff)
00096         return -1;
00097     dc  = s->last_dc[component];
00098     dc += diff;
00099     s->last_dc[component] = dc;
00100     block[0] = dc * quant_matrix[0];
00101     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
00102     i = 0;
00103     {
00104         OPEN_READER(re, &s->gb);
00105         /* now quantify & encode AC coefficients */
00106         for (;;) {
00107             UPDATE_CACHE(re, &s->gb);
00108             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00109 
00110             if (level == 127) {
00111                 break;
00112             } else if (level != 0) {
00113                 i += run;
00114                 j = scantable[i];
00115                 level = (level * qscale * quant_matrix[j]) >> 4;
00116                 level = (level - 1) | 1;
00117                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00118                 LAST_SKIP_BITS(re, &s->gb, 1);
00119             } else {
00120                 /* escape */
00121                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00122                 UPDATE_CACHE(re, &s->gb);
00123                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00124                 if (level == -128) {
00125                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
00126                 } else if (level == 0) {
00127                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
00128                 }
00129                 i += run;
00130                 j = scantable[i];
00131                 if (level < 0) {
00132                     level = -level;
00133                     level = (level * qscale * quant_matrix[j]) >> 4;
00134                     level = (level - 1) | 1;
00135                     level = -level;
00136                 } else {
00137                     level = (level * qscale * quant_matrix[j]) >> 4;
00138                     level = (level - 1) | 1;
00139                 }
00140             }
00141             if (i > 63) {
00142                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00143                 return -1;
00144             }
00145 
00146             block[j] = level;
00147         }
00148         CLOSE_READER(re, &s->gb);
00149     }
00150     s->block_last_index[n] = i;
00151    return 0;
00152 }
00153 
00154 int ff_mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00155 {
00156     return mpeg1_decode_block_intra(s, block, n);
00157 }
00158 
00159 static inline int mpeg1_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
00160 {
00161     int level, i, j, run;
00162     RLTable *rl = &ff_rl_mpeg1;
00163     uint8_t * const scantable    = s->intra_scantable.permutated;
00164     const uint16_t *quant_matrix = s->inter_matrix;
00165     const int qscale             = s->qscale;
00166 
00167     {
00168         OPEN_READER(re, &s->gb);
00169         i = -1;
00170         // special case for first coefficient, no need to add second VLC table
00171         UPDATE_CACHE(re, &s->gb);
00172         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00173             level = (3 * qscale * quant_matrix[0]) >> 5;
00174             level = (level - 1) | 1;
00175             if (GET_CACHE(re, &s->gb) & 0x40000000)
00176                 level = -level;
00177             block[0] = level;
00178             i++;
00179             SKIP_BITS(re, &s->gb, 2);
00180             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00181                 goto end;
00182         }
00183         /* now quantify & encode AC coefficients */
00184         for (;;) {
00185             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00186 
00187             if (level != 0) {
00188                 i += run;
00189                 j = scantable[i];
00190                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00191                 level = (level - 1) | 1;
00192                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00193                 SKIP_BITS(re, &s->gb, 1);
00194             } else {
00195                 /* escape */
00196                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00197                 UPDATE_CACHE(re, &s->gb);
00198                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00199                 if (level == -128) {
00200                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
00201                 } else if (level == 0) {
00202                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
00203                 }
00204                 i += run;
00205                 j = scantable[i];
00206                 if (level < 0) {
00207                     level = -level;
00208                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00209                     level = (level - 1) | 1;
00210                     level = -level;
00211                 } else {
00212                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00213                     level = (level - 1) | 1;
00214                 }
00215             }
00216             if (i > 63) {
00217                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00218                 return -1;
00219             }
00220 
00221             block[j] = level;
00222             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00223                 break;
00224             UPDATE_CACHE(re, &s->gb);
00225         }
00226 end:
00227         LAST_SKIP_BITS(re, &s->gb, 2);
00228         CLOSE_READER(re, &s->gb);
00229     }
00230     s->block_last_index[n] = i;
00231     return 0;
00232 }
00233 
00234 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
00235 {
00236     int level, i, j, run;
00237     RLTable *rl = &ff_rl_mpeg1;
00238     uint8_t * const scantable = s->intra_scantable.permutated;
00239     const int qscale          = s->qscale;
00240 
00241     {
00242         OPEN_READER(re, &s->gb);
00243         i = -1;
00244         // special case for first coefficient, no need to add second VLC table
00245         UPDATE_CACHE(re, &s->gb);
00246         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00247             level = (3 * qscale) >> 1;
00248             level = (level - 1) | 1;
00249             if (GET_CACHE(re, &s->gb) & 0x40000000)
00250                 level = -level;
00251             block[0] = level;
00252             i++;
00253             SKIP_BITS(re, &s->gb, 2);
00254             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00255                 goto end;
00256         }
00257 
00258         /* now quantify & encode AC coefficients */
00259         for (;;) {
00260             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00261 
00262             if (level != 0) {
00263                 i += run;
00264                 j = scantable[i];
00265                 level = ((level * 2 + 1) * qscale) >> 1;
00266                 level = (level - 1) | 1;
00267                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00268                 SKIP_BITS(re, &s->gb, 1);
00269             } else {
00270                 /* escape */
00271                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00272                 UPDATE_CACHE(re, &s->gb);
00273                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00274                 if (level == -128) {
00275                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
00276                 } else if (level == 0) {
00277                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
00278                 }
00279                 i += run;
00280                 j = scantable[i];
00281                 if (level < 0) {
00282                     level = -level;
00283                     level = ((level * 2 + 1) * qscale) >> 1;
00284                     level = (level - 1) | 1;
00285                     level = -level;
00286                 } else {
00287                     level = ((level * 2 + 1) * qscale) >> 1;
00288                     level = (level - 1) | 1;
00289                 }
00290             }
00291 
00292             block[j] = level;
00293             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00294                 break;
00295             UPDATE_CACHE(re, &s->gb);
00296         }
00297 end:
00298         LAST_SKIP_BITS(re, &s->gb, 2);
00299         CLOSE_READER(re, &s->gb);
00300     }
00301     s->block_last_index[n] = i;
00302     return 0;
00303 }
00304 
00305 
00306 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n)
00307 {
00308     int level, i, j, run;
00309     RLTable *rl = &ff_rl_mpeg1;
00310     uint8_t * const scantable = s->intra_scantable.permutated;
00311     const uint16_t *quant_matrix;
00312     const int qscale = s->qscale;
00313     int mismatch;
00314 
00315     mismatch = 1;
00316 
00317     {
00318         OPEN_READER(re, &s->gb);
00319         i = -1;
00320         if (n < 4)
00321             quant_matrix = s->inter_matrix;
00322         else
00323             quant_matrix = s->chroma_inter_matrix;
00324 
00325         // special case for first coefficient, no need to add second VLC table
00326         UPDATE_CACHE(re, &s->gb);
00327         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00328             level= (3 * qscale * quant_matrix[0]) >> 5;
00329             if (GET_CACHE(re, &s->gb) & 0x40000000)
00330                 level = -level;
00331             block[0]  = level;
00332             mismatch ^= level;
00333             i++;
00334             SKIP_BITS(re, &s->gb, 2);
00335             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00336                 goto end;
00337         }
00338 
00339         /* now quantify & encode AC coefficients */
00340         for (;;) {
00341             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00342 
00343             if (level != 0) {
00344                 i += run;
00345                 j = scantable[i];
00346                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00347                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00348                 SKIP_BITS(re, &s->gb, 1);
00349             } else {
00350                 /* escape */
00351                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00352                 UPDATE_CACHE(re, &s->gb);
00353                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00354 
00355                 i += run;
00356                 j = scantable[i];
00357                 if (level < 0) {
00358                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00359                     level = -level;
00360                 } else {
00361                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00362                 }
00363             }
00364             if (i > 63) {
00365                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00366                 return -1;
00367             }
00368 
00369             mismatch ^= level;
00370             block[j]  = level;
00371             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00372                 break;
00373             UPDATE_CACHE(re, &s->gb);
00374         }
00375 end:
00376         LAST_SKIP_BITS(re, &s->gb, 2);
00377         CLOSE_READER(re, &s->gb);
00378     }
00379     block[63] ^= (mismatch & 1);
00380 
00381     s->block_last_index[n] = i;
00382     return 0;
00383 }
00384 
00385 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
00386                                                     DCTELEM *block, int n)
00387 {
00388     int level, i, j, run;
00389     RLTable *rl = &ff_rl_mpeg1;
00390     uint8_t * const scantable = s->intra_scantable.permutated;
00391     const int qscale          = s->qscale;
00392     OPEN_READER(re, &s->gb);
00393     i = -1;
00394 
00395     // special case for first coefficient, no need to add second VLC table
00396     UPDATE_CACHE(re, &s->gb);
00397     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00398         level = (3 * qscale) >> 1;
00399         if (GET_CACHE(re, &s->gb) & 0x40000000)
00400             level = -level;
00401         block[0] = level;
00402         i++;
00403         SKIP_BITS(re, &s->gb, 2);
00404         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00405             goto end;
00406     }
00407 
00408     /* now quantify & encode AC coefficients */
00409     for (;;) {
00410         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00411 
00412         if (level != 0) {
00413             i += run;
00414             j  = scantable[i];
00415             level = ((level * 2 + 1) * qscale) >> 1;
00416             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00417             SKIP_BITS(re, &s->gb, 1);
00418         } else {
00419             /* escape */
00420             run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00421             UPDATE_CACHE(re, &s->gb);
00422             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00423 
00424             i += run;
00425             j  = scantable[i];
00426             if (level < 0) {
00427                 level = ((-level * 2 + 1) * qscale) >> 1;
00428                 level = -level;
00429             } else {
00430                 level = ((level * 2 + 1) * qscale) >> 1;
00431             }
00432         }
00433 
00434         block[j] = level;
00435         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00436             break;
00437         UPDATE_CACHE(re, &s->gb);
00438     }
00439 end:
00440     LAST_SKIP_BITS(re, &s->gb, 2);
00441     CLOSE_READER(re, &s->gb);
00442     s->block_last_index[n] = i;
00443     return 0;
00444 }
00445 
00446 
00447 static inline int mpeg2_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00448 {
00449     int level, dc, diff, i, j, run;
00450     int component;
00451     RLTable *rl;
00452     uint8_t * const scantable = s->intra_scantable.permutated;
00453     const uint16_t *quant_matrix;
00454     const int qscale = s->qscale;
00455     int mismatch;
00456 
00457     /* DC coefficient */
00458     if (n < 4) {
00459         quant_matrix = s->intra_matrix;
00460         component = 0;
00461     } else {
00462         quant_matrix = s->chroma_intra_matrix;
00463         component = (n & 1) + 1;
00464     }
00465     diff = decode_dc(&s->gb, component);
00466     if (diff >= 0xffff)
00467         return -1;
00468     dc  = s->last_dc[component];
00469     dc += diff;
00470     s->last_dc[component] = dc;
00471     block[0] = dc << (3 - s->intra_dc_precision);
00472     av_dlog(s->avctx, "dc=%d\n", block[0]);
00473     mismatch = block[0] ^ 1;
00474     i = 0;
00475     if (s->intra_vlc_format)
00476         rl = &ff_rl_mpeg2;
00477     else
00478         rl = &ff_rl_mpeg1;
00479 
00480     {
00481         OPEN_READER(re, &s->gb);
00482         /* now quantify & encode AC coefficients */
00483         for (;;) {
00484             UPDATE_CACHE(re, &s->gb);
00485             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00486 
00487             if (level == 127) {
00488                 break;
00489             } else if (level != 0) {
00490                 i += run;
00491                 j  = scantable[i];
00492                 level = (level * qscale * quant_matrix[j]) >> 4;
00493                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00494                 LAST_SKIP_BITS(re, &s->gb, 1);
00495             } else {
00496                 /* escape */
00497                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00498                 UPDATE_CACHE(re, &s->gb);
00499                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00500                 i += run;
00501                 j  = scantable[i];
00502                 if (level < 0) {
00503                     level = (-level * qscale * quant_matrix[j]) >> 4;
00504                     level = -level;
00505                 } else {
00506                     level = (level * qscale * quant_matrix[j]) >> 4;
00507                 }
00508             }
00509             if (i > 63) {
00510                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00511                 return -1;
00512             }
00513 
00514             mismatch ^= level;
00515             block[j]  = level;
00516         }
00517         CLOSE_READER(re, &s->gb);
00518     }
00519     block[63] ^= mismatch & 1;
00520 
00521     s->block_last_index[n] = i;
00522     return 0;
00523 }
00524 
00525 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00526 {
00527     int level, dc, diff, j, run;
00528     int component;
00529     RLTable *rl;
00530     uint8_t * scantable = s->intra_scantable.permutated;
00531     const uint16_t *quant_matrix;
00532     const int qscale = s->qscale;
00533 
00534     /* DC coefficient */
00535     if (n < 4) {
00536         quant_matrix = s->intra_matrix;
00537         component = 0;
00538     } else {
00539         quant_matrix = s->chroma_intra_matrix;
00540         component = (n & 1) + 1;
00541     }
00542     diff = decode_dc(&s->gb, component);
00543     if (diff >= 0xffff)
00544         return -1;
00545     dc = s->last_dc[component];
00546     dc += diff;
00547     s->last_dc[component] = dc;
00548     block[0] = dc << (3 - s->intra_dc_precision);
00549     if (s->intra_vlc_format)
00550         rl = &ff_rl_mpeg2;
00551     else
00552         rl = &ff_rl_mpeg1;
00553 
00554     {
00555         OPEN_READER(re, &s->gb);
00556         /* now quantify & encode AC coefficients */
00557         for (;;) {
00558             UPDATE_CACHE(re, &s->gb);
00559             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00560 
00561             if (level == 127) {
00562                 break;
00563             } else if (level != 0) {
00564                 scantable += run;
00565                 j = *scantable;
00566                 level = (level * qscale * quant_matrix[j]) >> 4;
00567                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00568                 LAST_SKIP_BITS(re, &s->gb, 1);
00569             } else {
00570                 /* escape */
00571                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00572                 UPDATE_CACHE(re, &s->gb);
00573                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00574                 scantable += run;
00575                 j = *scantable;
00576                 if (level < 0) {
00577                     level = (-level * qscale * quant_matrix[j]) >> 4;
00578                     level = -level;
00579                 } else {
00580                     level = (level * qscale * quant_matrix[j]) >> 4;
00581                 }
00582             }
00583 
00584             block[j] = level;
00585         }
00586         CLOSE_READER(re, &s->gb);
00587     }
00588 
00589     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
00590     return 0;
00591 }
00592 
00593 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
00594 
00595 #define INIT_2D_VLC_RL(rl, static_size)\
00596 {\
00597     static RL_VLC_ELEM rl_vlc_table[static_size];\
00598     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
00599                     &rl.table_vlc[0][1], 4, 2,\
00600                     &rl.table_vlc[0][0], 4, 2, static_size);\
00601 \
00602     rl.rl_vlc[0] = rl_vlc_table;\
00603     init_2d_vlc_rl(&rl);\
00604 }
00605 
00606 static void init_2d_vlc_rl(RLTable *rl)
00607 {
00608     int i;
00609 
00610     for (i = 0; i < rl->vlc.table_size; i++) {
00611         int code = rl->vlc.table[i][0];
00612         int len  = rl->vlc.table[i][1];
00613         int level, run;
00614 
00615         if (len == 0) { // illegal code
00616             run   = 65;
00617             level = MAX_LEVEL;
00618         } else if (len<0) { //more bits needed
00619             run   = 0;
00620             level = code;
00621         } else {
00622             if (code == rl->n) { //esc
00623                 run   = 65;
00624                 level = 0;
00625             } else if (code == rl->n+1) { //eob
00626                 run   = 0;
00627                 level = 127;
00628             } else {
00629                 run   = rl->table_run  [code] + 1;
00630                 level = rl->table_level[code];
00631             }
00632         }
00633         rl->rl_vlc[0][i].len   = len;
00634         rl->rl_vlc[0][i].level = level;
00635         rl->rl_vlc[0][i].run   = run;
00636     }
00637 }
00638 
00639 void ff_mpeg12_common_init(MpegEncContext *s)
00640 {
00641 
00642     s->y_dc_scale_table =
00643     s->c_dc_scale_table = ff_mpeg2_dc_scale_table[s->intra_dc_precision];
00644 
00645 }
00646 
00647 void ff_mpeg1_clean_buffers(MpegEncContext *s)
00648 {
00649     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
00650     s->last_dc[1] = s->last_dc[0];
00651     s->last_dc[2] = s->last_dc[0];
00652     memset(s->last_mv, 0, sizeof(s->last_mv));
00653 }
00654 
00655 
00656 /******************************************/
00657 /* decoding */
00658 
00659 VLC ff_dc_lum_vlc;
00660 VLC ff_dc_chroma_vlc;
00661 
00662 static VLC mbincr_vlc;
00663 static VLC mb_ptype_vlc;
00664 static VLC mb_btype_vlc;
00665 static VLC mb_pat_vlc;
00666 
00667 av_cold void ff_mpeg12_init_vlcs(void)
00668 {
00669     static int done = 0;
00670 
00671     if (!done) {
00672         done = 1;
00673 
00674         INIT_VLC_STATIC(&ff_dc_lum_vlc, DC_VLC_BITS, 12,
00675                         ff_mpeg12_vlc_dc_lum_bits, 1, 1,
00676                         ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
00677         INIT_VLC_STATIC(&ff_dc_chroma_vlc,  DC_VLC_BITS, 12,
00678                         ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
00679                         ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
00680         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
00681                         &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
00682                         &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
00683         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
00684                         &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
00685                         &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
00686         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
00687                         &ff_mpeg12_mbPatTable[0][1], 2, 1,
00688                         &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
00689 
00690         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
00691                         &table_mb_ptype[0][1], 2, 1,
00692                         &table_mb_ptype[0][0], 2, 1, 64);
00693         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
00694                         &table_mb_btype[0][1], 2, 1,
00695                         &table_mb_btype[0][0], 2, 1, 64);
00696         init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
00697         init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
00698 
00699         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
00700         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
00701     }
00702 }
00703 
00704 static inline int get_dmv(MpegEncContext *s)
00705 {
00706     if (get_bits1(&s->gb))
00707         return 1 - (get_bits1(&s->gb) << 1);
00708     else
00709         return 0;
00710 }
00711 
00712 static inline int get_qscale(MpegEncContext *s)
00713 {
00714     int qscale = get_bits(&s->gb, 5);
00715     if (s->q_scale_type) {
00716         return non_linear_qscale[qscale];
00717     } else {
00718         return qscale << 1;
00719     }
00720 }
00721 
00722 static void exchange_uv(MpegEncContext *s)
00723 {
00724     DCTELEM (*tmp)[64];
00725 
00726     tmp           = s->pblocks[4];
00727     s->pblocks[4] = s->pblocks[5];
00728     s->pblocks[5] = tmp;
00729 }
00730 
00731 /* motion type (for MPEG-2) */
00732 #define MT_FIELD 1
00733 #define MT_FRAME 2
00734 #define MT_16X8  2
00735 #define MT_DMV   3
00736 
00737 static int mpeg_decode_mb(MpegEncContext *s, DCTELEM block[12][64])
00738 {
00739     int i, j, k, cbp, val, mb_type, motion_type;
00740     const int mb_block_count = 4 + (1 << s->chroma_format);
00741 
00742     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
00743 
00744     assert(s->mb_skipped == 0);
00745 
00746     if (s->mb_skip_run-- != 0) {
00747         if (s->pict_type == AV_PICTURE_TYPE_P) {
00748             s->mb_skipped = 1;
00749             s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
00750         } else {
00751             int mb_type;
00752 
00753             if (s->mb_x)
00754                 mb_type = s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
00755             else
00756                 mb_type = s->current_picture.f.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1]; // FIXME not sure if this is allowed in MPEG at all
00757             if (IS_INTRA(mb_type))
00758                 return -1;
00759             s->current_picture.f.mb_type[s->mb_x + s->mb_y*s->mb_stride] =
00760                 mb_type | MB_TYPE_SKIP;
00761 //            assert(s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
00762 
00763             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
00764                 s->mb_skipped = 1;
00765         }
00766 
00767         return 0;
00768     }
00769 
00770     switch (s->pict_type) {
00771     default:
00772     case AV_PICTURE_TYPE_I:
00773         if (get_bits1(&s->gb) == 0) {
00774             if (get_bits1(&s->gb) == 0) {
00775                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
00776                 return -1;
00777             }
00778             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
00779         } else {
00780             mb_type = MB_TYPE_INTRA;
00781         }
00782         break;
00783     case AV_PICTURE_TYPE_P:
00784         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
00785         if (mb_type < 0) {
00786             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
00787             return -1;
00788         }
00789         mb_type = ptype2mb_type[mb_type];
00790         break;
00791     case AV_PICTURE_TYPE_B:
00792         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
00793         if (mb_type < 0) {
00794             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
00795             return -1;
00796         }
00797         mb_type = btype2mb_type[mb_type];
00798         break;
00799     }
00800     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
00801 //    motion_type = 0; /* avoid warning */
00802     if (IS_INTRA(mb_type)) {
00803         s->dsp.clear_blocks(s->block[0]);
00804 
00805         if (!s->chroma_y_shift) {
00806             s->dsp.clear_blocks(s->block[6]);
00807         }
00808 
00809         /* compute DCT type */
00810         if (s->picture_structure == PICT_FRAME && // FIXME add an interlaced_dct coded var?
00811             !s->frame_pred_frame_dct) {
00812             s->interlaced_dct = get_bits1(&s->gb);
00813         }
00814 
00815         if (IS_QUANT(mb_type))
00816             s->qscale = get_qscale(s);
00817 
00818         if (s->concealment_motion_vectors) {
00819             /* just parse them */
00820             if (s->picture_structure != PICT_FRAME)
00821                 skip_bits1(&s->gb); /* field select */
00822 
00823             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
00824                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
00825             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
00826                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
00827 
00828             skip_bits1(&s->gb); /* marker */
00829         } else
00830             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
00831         s->mb_intra = 1;
00832         // if 1, we memcpy blocks in xvmcvideo
00833         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
00834             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
00835             if (s->swap_uv) {
00836                 exchange_uv(s);
00837             }
00838         }
00839 
00840         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
00841             if (s->flags2 & CODEC_FLAG2_FAST) {
00842                 for (i = 0; i < 6; i++) {
00843                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
00844                 }
00845             } else {
00846                 for (i = 0; i < mb_block_count; i++) {
00847                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
00848                         return -1;
00849                 }
00850             }
00851         } else {
00852             for (i = 0; i < 6; i++) {
00853                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
00854                     return -1;
00855             }
00856         }
00857     } else {
00858         if (mb_type & MB_TYPE_ZERO_MV) {
00859             assert(mb_type & MB_TYPE_CBP);
00860 
00861             s->mv_dir = MV_DIR_FORWARD;
00862             if (s->picture_structure == PICT_FRAME) {
00863                 if (!s->frame_pred_frame_dct)
00864                     s->interlaced_dct = get_bits1(&s->gb);
00865                 s->mv_type = MV_TYPE_16X16;
00866             } else {
00867                 s->mv_type = MV_TYPE_FIELD;
00868                 mb_type |= MB_TYPE_INTERLACED;
00869                 s->field_select[0][0] = s->picture_structure - 1;
00870             }
00871 
00872             if (IS_QUANT(mb_type))
00873                 s->qscale = get_qscale(s);
00874 
00875             s->last_mv[0][0][0] = 0;
00876             s->last_mv[0][0][1] = 0;
00877             s->last_mv[0][1][0] = 0;
00878             s->last_mv[0][1][1] = 0;
00879             s->mv[0][0][0] = 0;
00880             s->mv[0][0][1] = 0;
00881         } else {
00882             assert(mb_type & MB_TYPE_L0L1);
00883             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
00884             /* get additional motion vector type */
00885             if (s->frame_pred_frame_dct)
00886                 motion_type = MT_FRAME;
00887             else {
00888                 motion_type = get_bits(&s->gb, 2);
00889                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
00890                     s->interlaced_dct = get_bits1(&s->gb);
00891             }
00892 
00893             if (IS_QUANT(mb_type))
00894                 s->qscale = get_qscale(s);
00895 
00896             /* motion vectors */
00897             s->mv_dir = (mb_type >> 13) & 3;
00898             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
00899             switch (motion_type) {
00900             case MT_FRAME: /* or MT_16X8 */
00901                 if (s->picture_structure == PICT_FRAME) {
00902                     mb_type |= MB_TYPE_16x16;
00903                     s->mv_type = MV_TYPE_16X16;
00904                     for (i = 0; i < 2; i++) {
00905                         if (USES_LIST(mb_type, i)) {
00906                             /* MT_FRAME */
00907                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
00908                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
00909                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
00910                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
00911                             /* full_pel: only for MPEG-1 */
00912                             if (s->full_pel[i]) {
00913                                 s->mv[i][0][0] <<= 1;
00914                                 s->mv[i][0][1] <<= 1;
00915                             }
00916                         }
00917                     }
00918                 } else {
00919                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
00920                     s->mv_type = MV_TYPE_16X8;
00921                     for (i = 0; i < 2; i++) {
00922                         if (USES_LIST(mb_type, i)) {
00923                             /* MT_16X8 */
00924                             for (j = 0; j < 2; j++) {
00925                                 s->field_select[i][j] = get_bits1(&s->gb);
00926                                 for (k = 0; k < 2; k++) {
00927                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
00928                                                              s->last_mv[i][j][k]);
00929                                     s->last_mv[i][j][k] = val;
00930                                     s->mv[i][j][k]      = val;
00931                                 }
00932                             }
00933                         }
00934                     }
00935                 }
00936                 break;
00937             case MT_FIELD:
00938                 s->mv_type = MV_TYPE_FIELD;
00939                 if (s->picture_structure == PICT_FRAME) {
00940                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
00941                     for (i = 0; i < 2; i++) {
00942                         if (USES_LIST(mb_type, i)) {
00943                             for (j = 0; j < 2; j++) {
00944                                 s->field_select[i][j] = get_bits1(&s->gb);
00945                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
00946                                                          s->last_mv[i][j][0]);
00947                                 s->last_mv[i][j][0] = val;
00948                                 s->mv[i][j][0]      = val;
00949                                 av_dlog(s->avctx, "fmx=%d\n", val);
00950                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
00951                                                          s->last_mv[i][j][1] >> 1);
00952                                 s->last_mv[i][j][1] = val << 1;
00953                                 s->mv[i][j][1]      = val;
00954                                 av_dlog(s->avctx, "fmy=%d\n", val);
00955                             }
00956                         }
00957                     }
00958                 } else {
00959                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
00960                     for (i = 0; i < 2; i++) {
00961                         if (USES_LIST(mb_type, i)) {
00962                             s->field_select[i][0] = get_bits1(&s->gb);
00963                             for (k = 0; k < 2; k++) {
00964                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
00965                                                          s->last_mv[i][0][k]);
00966                                 s->last_mv[i][0][k] = val;
00967                                 s->last_mv[i][1][k] = val;
00968                                 s->mv[i][0][k]      = val;
00969                             }
00970                         }
00971                     }
00972                 }
00973                 break;
00974             case MT_DMV:
00975                 s->mv_type = MV_TYPE_DMV;
00976                 for (i = 0; i < 2; i++) {
00977                     if (USES_LIST(mb_type, i)) {
00978                         int dmx, dmy, mx, my, m;
00979                         const int my_shift = s->picture_structure == PICT_FRAME;
00980 
00981                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
00982                                                 s->last_mv[i][0][0]);
00983                         s->last_mv[i][0][0] = mx;
00984                         s->last_mv[i][1][0] = mx;
00985                         dmx = get_dmv(s);
00986                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
00987                                                  s->last_mv[i][0][1] >> my_shift);
00988                         dmy = get_dmv(s);
00989 
00990 
00991                         s->last_mv[i][0][1] = my << my_shift;
00992                         s->last_mv[i][1][1] = my << my_shift;
00993 
00994                         s->mv[i][0][0] = mx;
00995                         s->mv[i][0][1] = my;
00996                         s->mv[i][1][0] = mx; // not used
00997                         s->mv[i][1][1] = my; // not used
00998 
00999                         if (s->picture_structure == PICT_FRAME) {
01000                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
01001 
01002                             // m = 1 + 2 * s->top_field_first;
01003                             m = s->top_field_first ? 1 : 3;
01004 
01005                             /* top -> top pred */
01006                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
01007                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
01008                             m = 4 - m;
01009                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
01010                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
01011                         } else {
01012                             mb_type |= MB_TYPE_16x16;
01013 
01014                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
01015                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
01016                             if (s->picture_structure == PICT_TOP_FIELD)
01017                                 s->mv[i][2][1]--;
01018                             else
01019                                 s->mv[i][2][1]++;
01020                         }
01021                     }
01022                 }
01023                 break;
01024             default:
01025                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
01026                 return -1;
01027             }
01028         }
01029 
01030         s->mb_intra = 0;
01031         if (HAS_CBP(mb_type)) {
01032             s->dsp.clear_blocks(s->block[0]);
01033 
01034             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
01035             if (mb_block_count > 6) {
01036                  cbp <<= mb_block_count - 6;
01037                  cbp  |= get_bits(&s->gb, mb_block_count - 6);
01038                  s->dsp.clear_blocks(s->block[6]);
01039             }
01040             if (cbp <= 0) {
01041                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
01042                 return -1;
01043             }
01044 
01045             //if 1, we memcpy blocks in xvmcvideo
01046             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
01047                 ff_xvmc_pack_pblocks(s, cbp);
01048                 if (s->swap_uv) {
01049                     exchange_uv(s);
01050                 }
01051             }
01052 
01053             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
01054                 if (s->flags2 & CODEC_FLAG2_FAST) {
01055                     for (i = 0; i < 6; i++) {
01056                         if (cbp & 32) {
01057                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
01058                         } else {
01059                             s->block_last_index[i] = -1;
01060                         }
01061                         cbp += cbp;
01062                     }
01063                 } else {
01064                     cbp <<= 12-mb_block_count;
01065 
01066                     for (i = 0; i < mb_block_count; i++) {
01067                         if (cbp & (1 << 11)) {
01068                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
01069                                 return -1;
01070                         } else {
01071                             s->block_last_index[i] = -1;
01072                         }
01073                         cbp += cbp;
01074                     }
01075                 }
01076             } else {
01077                 if (s->flags2 & CODEC_FLAG2_FAST) {
01078                     for (i = 0; i < 6; i++) {
01079                         if (cbp & 32) {
01080                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
01081                         } else {
01082                             s->block_last_index[i] = -1;
01083                         }
01084                         cbp += cbp;
01085                     }
01086                 } else {
01087                     for (i = 0; i < 6; i++) {
01088                         if (cbp & 32) {
01089                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
01090                                 return -1;
01091                         } else {
01092                             s->block_last_index[i] = -1;
01093                         }
01094                         cbp += cbp;
01095                     }
01096                 }
01097             }
01098         } else {
01099             for (i = 0; i < 12; i++)
01100                 s->block_last_index[i] = -1;
01101         }
01102     }
01103 
01104     s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
01105 
01106     return 0;
01107 }
01108 
01109 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
01110 {
01111     Mpeg1Context *s = avctx->priv_data;
01112     MpegEncContext *s2 = &s->mpeg_enc_ctx;
01113     int i;
01114 
01115     /* we need some permutation to store matrices,
01116      * until MPV_common_init() sets the real permutation. */
01117     for (i = 0; i < 64; i++)
01118        s2->dsp.idct_permutation[i]=i;
01119 
01120     MPV_decode_defaults(s2);
01121 
01122     s->mpeg_enc_ctx.avctx  = avctx;
01123     s->mpeg_enc_ctx.flags  = avctx->flags;
01124     s->mpeg_enc_ctx.flags2 = avctx->flags2;
01125     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
01126     ff_mpeg12_init_vlcs();
01127 
01128     s->mpeg_enc_ctx_allocated      = 0;
01129     s->mpeg_enc_ctx.picture_number = 0;
01130     s->repeat_field                = 0;
01131     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
01132     avctx->color_range = AVCOL_RANGE_MPEG;
01133     if (avctx->codec->id == CODEC_ID_MPEG1VIDEO)
01134         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
01135     else
01136         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
01137     return 0;
01138 }
01139 
01140 static int mpeg_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
01141 {
01142     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
01143     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
01144     int err;
01145 
01146     if (avctx == avctx_from || !ctx_from->mpeg_enc_ctx_allocated || !s1->context_initialized)
01147         return 0;
01148 
01149     err = ff_mpeg_update_thread_context(avctx, avctx_from);
01150     if (err) return err;
01151 
01152     if (!ctx->mpeg_enc_ctx_allocated)
01153         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
01154 
01155     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
01156         s->picture_number++;
01157 
01158     return 0;
01159 }
01160 
01161 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
01162                                  const uint8_t *new_perm)
01163 {
01164     uint16_t temp_matrix[64];
01165     int i;
01166 
01167     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
01168 
01169     for (i = 0; i < 64; i++) {
01170         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
01171     }
01172 }
01173 
01174 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
01175     PIX_FMT_XVMC_MPEG2_IDCT,
01176     PIX_FMT_XVMC_MPEG2_MC,
01177     PIX_FMT_NONE };
01178 
01179 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
01180 {
01181     Mpeg1Context *s1 = avctx->priv_data;
01182     MpegEncContext *s = &s1->mpeg_enc_ctx;
01183 
01184     if (avctx->xvmc_acceleration)
01185         return avctx->get_format(avctx, pixfmt_xvmc_mpg2_420);
01186     else if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
01187         if (avctx->codec_id == CODEC_ID_MPEG1VIDEO)
01188             return PIX_FMT_VDPAU_MPEG1;
01189         else
01190             return PIX_FMT_VDPAU_MPEG2;
01191     } else {
01192         if (s->chroma_format <  2)
01193             return avctx->get_format(avctx, ff_hwaccel_pixfmt_list_420);
01194         else if (s->chroma_format == 2)
01195             return PIX_FMT_YUV422P;
01196         else
01197             return PIX_FMT_YUV444P;
01198     }
01199 }
01200 
01201 /* Call this function when we know all parameters.
01202  * It may be called in different places for MPEG-1 and MPEG-2. */
01203 static int mpeg_decode_postinit(AVCodecContext *avctx)
01204 {
01205     Mpeg1Context *s1 = avctx->priv_data;
01206     MpegEncContext *s = &s1->mpeg_enc_ctx;
01207     uint8_t old_permutation[64];
01208 
01209     if ((s1->mpeg_enc_ctx_allocated == 0) ||
01210         avctx->coded_width  != s->width   ||
01211         avctx->coded_height != s->height  ||
01212         s1->save_width           != s->width                ||
01213         s1->save_height          != s->height               ||
01214         s1->save_aspect_info     != s->aspect_ratio_info    ||
01215         s1->save_progressive_seq != s->progressive_sequence ||
01216         0)
01217     {
01218 
01219         if (s1->mpeg_enc_ctx_allocated) {
01220             ParseContext pc = s->parse_context;
01221             s->parse_context.buffer = 0;
01222             MPV_common_end(s);
01223             s->parse_context = pc;
01224         }
01225 
01226         if ((s->width == 0) || (s->height == 0))
01227             return -2;
01228 
01229         avcodec_set_dimensions(avctx, s->width, s->height);
01230         avctx->bit_rate          = s->bit_rate;
01231         s1->save_aspect_info     = s->aspect_ratio_info;
01232         s1->save_width           = s->width;
01233         s1->save_height          = s->height;
01234         s1->save_progressive_seq = s->progressive_sequence;
01235 
01236         /* low_delay may be forced, in this case we will have B-frames
01237          * that behave like P-frames. */
01238         avctx->has_b_frames = !s->low_delay;
01239 
01240         assert((avctx->sub_id == 1) == (avctx->codec_id == CODEC_ID_MPEG1VIDEO));
01241         if (avctx->codec_id == CODEC_ID_MPEG1VIDEO) {
01242             //MPEG-1 fps
01243             avctx->time_base.den = avpriv_frame_rate_tab[s->frame_rate_index].num;
01244             avctx->time_base.num = avpriv_frame_rate_tab[s->frame_rate_index].den;
01245             //MPEG-1 aspect
01246             avctx->sample_aspect_ratio = av_d2q(1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
01247             avctx->ticks_per_frame=1;
01248         } else {//MPEG-2
01249         //MPEG-2 fps
01250             av_reduce(&s->avctx->time_base.den,
01251                       &s->avctx->time_base.num,
01252                       avpriv_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
01253                       avpriv_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
01254                       1 << 30);
01255             avctx->ticks_per_frame = 2;
01256             //MPEG-2 aspect
01257             if (s->aspect_ratio_info > 1) {
01258                 AVRational dar =
01259                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
01260                                       (AVRational) {s1->pan_scan.width, s1->pan_scan.height}),
01261                              (AVRational) {s->width, s->height});
01262 
01263                 // we ignore the spec here and guess a bit as reality does not match the spec, see for example
01264                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
01265                 // issue1613, 621, 562
01266                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
01267                    (av_cmp_q(dar, (AVRational) {4, 3}) && av_cmp_q(dar, (AVRational) {16, 9}))) {
01268                     s->avctx->sample_aspect_ratio =
01269                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
01270                                  (AVRational) {s->width, s->height});
01271                 } else {
01272                     s->avctx->sample_aspect_ratio =
01273                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
01274                                  (AVRational) {s1->pan_scan.width, s1->pan_scan.height});
01275 //issue1613 4/3 16/9 -> 16/9
01276 //res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
01277 //widescreen-issue562.mpg 4/3 16/9 -> 16/9
01278 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
01279 //av_log(NULL, AV_LOG_ERROR, "A %d/%d\n", ff_mpeg2_aspect[s->aspect_ratio_info].num, ff_mpeg2_aspect[s->aspect_ratio_info].den);
01280 //av_log(NULL, AV_LOG_ERROR, "B %d/%d\n", s->avctx->sample_aspect_ratio.num, s->avctx->sample_aspect_ratio.den);
01281                 }
01282             } else {
01283                 s->avctx->sample_aspect_ratio =
01284                     ff_mpeg2_aspect[s->aspect_ratio_info];
01285             }
01286         } // MPEG-2
01287 
01288         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
01289         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
01290         // until then pix_fmt may be changed right after codec init
01291         if (avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
01292             avctx->hwaccel                            ||
01293             s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
01294             if (avctx->idct_algo == FF_IDCT_AUTO)
01295                 avctx->idct_algo = FF_IDCT_SIMPLE;
01296 
01297         /* Quantization matrices may need reordering
01298          * if DCT permutation is changed. */
01299         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
01300 
01301         if (MPV_common_init(s) < 0)
01302             return -2;
01303 
01304         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
01305         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->dsp.idct_permutation);
01306         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->dsp.idct_permutation);
01307         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->dsp.idct_permutation);
01308 
01309         s1->mpeg_enc_ctx_allocated = 1;
01310     }
01311     return 0;
01312 }
01313 
01314 static int mpeg1_decode_picture(AVCodecContext *avctx,
01315                                 const uint8_t *buf, int buf_size)
01316 {
01317     Mpeg1Context *s1 = avctx->priv_data;
01318     MpegEncContext *s = &s1->mpeg_enc_ctx;
01319     int ref, f_code, vbv_delay;
01320 
01321     init_get_bits(&s->gb, buf, buf_size*8);
01322 
01323     ref = get_bits(&s->gb, 10); /* temporal ref */
01324     s->pict_type = get_bits(&s->gb, 3);
01325     if (s->pict_type == 0 || s->pict_type > 3)
01326         return -1;
01327 
01328     vbv_delay = get_bits(&s->gb, 16);
01329     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) {
01330         s->full_pel[0] = get_bits1(&s->gb);
01331         f_code = get_bits(&s->gb, 3);
01332         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
01333             return -1;
01334         s->mpeg_f_code[0][0] = f_code;
01335         s->mpeg_f_code[0][1] = f_code;
01336     }
01337     if (s->pict_type == AV_PICTURE_TYPE_B) {
01338         s->full_pel[1] = get_bits1(&s->gb);
01339         f_code = get_bits(&s->gb, 3);
01340         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
01341             return -1;
01342         s->mpeg_f_code[1][0] = f_code;
01343         s->mpeg_f_code[1][1] = f_code;
01344     }
01345     s->current_picture.f.pict_type = s->pict_type;
01346     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
01347 
01348     if (avctx->debug & FF_DEBUG_PICT_INFO)
01349         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
01350 
01351     s->y_dc_scale = 8;
01352     s->c_dc_scale = 8;
01353     return 0;
01354 }
01355 
01356 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
01357 {
01358     MpegEncContext *s= &s1->mpeg_enc_ctx;
01359     int horiz_size_ext, vert_size_ext;
01360     int bit_rate_ext;
01361 
01362     skip_bits(&s->gb, 1); /* profile and level esc*/
01363     s->avctx->profile       = get_bits(&s->gb, 3);
01364     s->avctx->level         = get_bits(&s->gb, 4);
01365     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
01366     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
01367     horiz_size_ext          = get_bits(&s->gb, 2);
01368     vert_size_ext           = get_bits(&s->gb, 2);
01369     s->width  |= (horiz_size_ext << 12);
01370     s->height |= (vert_size_ext  << 12);
01371     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
01372     s->bit_rate += (bit_rate_ext << 18) * 400;
01373     skip_bits1(&s->gb); /* marker */
01374     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
01375 
01376     s->low_delay = get_bits1(&s->gb);
01377     if (s->flags & CODEC_FLAG_LOW_DELAY)
01378         s->low_delay = 1;
01379 
01380     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
01381     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
01382 
01383     av_dlog(s->avctx, "sequence extension\n");
01384     s->codec_id      = s->avctx->codec_id = CODEC_ID_MPEG2VIDEO;
01385     s->avctx->sub_id = 2; /* indicates MPEG-2 found */
01386 
01387     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01388         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
01389                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
01390 
01391 }
01392 
01393 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
01394 {
01395     MpegEncContext *s = &s1->mpeg_enc_ctx;
01396     int color_description, w, h;
01397 
01398     skip_bits(&s->gb, 3); /* video format */
01399     color_description = get_bits1(&s->gb);
01400     if (color_description) {
01401         s->avctx->color_primaries = get_bits(&s->gb, 8);
01402         s->avctx->color_trc       = get_bits(&s->gb, 8);
01403         s->avctx->colorspace      = get_bits(&s->gb, 8);
01404     }
01405     w = get_bits(&s->gb, 14);
01406     skip_bits(&s->gb, 1); //marker
01407     h = get_bits(&s->gb, 14);
01408     // remaining 3 bits are zero padding
01409 
01410     s1->pan_scan.width  = 16 * w;
01411     s1->pan_scan.height = 16 * h;
01412 
01413     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01414         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
01415 }
01416 
01417 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
01418 {
01419     MpegEncContext *s = &s1->mpeg_enc_ctx;
01420     int i, nofco;
01421 
01422     nofco = 1;
01423     if (s->progressive_sequence) {
01424         if (s->repeat_first_field) {
01425             nofco++;
01426             if (s->top_field_first)
01427                 nofco++;
01428         }
01429     } else {
01430         if (s->picture_structure == PICT_FRAME) {
01431             nofco++;
01432             if (s->repeat_first_field)
01433                 nofco++;
01434         }
01435     }
01436     for (i = 0; i < nofco; i++) {
01437         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
01438         skip_bits(&s->gb, 1); // marker
01439         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
01440         skip_bits(&s->gb, 1); // marker
01441     }
01442 
01443     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01444         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
01445                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
01446                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
01447                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
01448 }
01449 
01450 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra)
01451 {
01452     int i;
01453 
01454     for (i = 0; i < 64; i++) {
01455         int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
01456         int v = get_bits(&s->gb, 8);
01457         if (v == 0) {
01458             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
01459             return -1;
01460         }
01461         if (intra && i == 0 && v != 8) {
01462             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
01463             v = 8; // needed by pink.mpg / issue1046
01464         }
01465         matrix0[j] = v;
01466         if (matrix1)
01467             matrix1[j] = v;
01468     }
01469     return 0;
01470 }
01471 
01472 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
01473 {
01474     av_dlog(s->avctx, "matrix extension\n");
01475 
01476     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
01477     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
01478     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
01479     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
01480 }
01481 
01482 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
01483 {
01484     MpegEncContext *s = &s1->mpeg_enc_ctx;
01485 
01486     s->full_pel[0] = s->full_pel[1] = 0;
01487     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
01488     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
01489     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
01490     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
01491     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
01492         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
01493         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
01494             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
01495                 s->pict_type = AV_PICTURE_TYPE_I;
01496             else
01497                 s->pict_type = AV_PICTURE_TYPE_P;
01498         } else
01499             s->pict_type = AV_PICTURE_TYPE_B;
01500         s->current_picture.f.pict_type = s->pict_type;
01501         s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
01502     }
01503     s->intra_dc_precision         = get_bits(&s->gb, 2);
01504     s->picture_structure          = get_bits(&s->gb, 2);
01505     s->top_field_first            = get_bits1(&s->gb);
01506     s->frame_pred_frame_dct       = get_bits1(&s->gb);
01507     s->concealment_motion_vectors = get_bits1(&s->gb);
01508     s->q_scale_type               = get_bits1(&s->gb);
01509     s->intra_vlc_format           = get_bits1(&s->gb);
01510     s->alternate_scan             = get_bits1(&s->gb);
01511     s->repeat_first_field         = get_bits1(&s->gb);
01512     s->chroma_420_type            = get_bits1(&s->gb);
01513     s->progressive_frame          = get_bits1(&s->gb);
01514 
01515     if (s->progressive_sequence && !s->progressive_frame) {
01516         s->progressive_frame = 1;
01517         av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
01518     }
01519 
01520     if (s->picture_structure == 0 || (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
01521         av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
01522         s->picture_structure = PICT_FRAME;
01523     }
01524 
01525     if (s->progressive_sequence && !s->frame_pred_frame_dct) {
01526         av_log(s->avctx, AV_LOG_ERROR, "invalid frame_pred_frame_dct\n");
01527         s->frame_pred_frame_dct = 1;
01528     }
01529 
01530     if (s->picture_structure == PICT_FRAME) {
01531         s->first_field = 0;
01532         s->v_edge_pos  = 16 * s->mb_height;
01533     } else {
01534         s->first_field ^= 1;
01535         s->v_edge_pos   = 8 * s->mb_height;
01536         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
01537     }
01538 
01539     if (s->alternate_scan) {
01540         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
01541         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
01542     } else {
01543         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
01544         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
01545     }
01546 
01547     /* composite display not parsed */
01548     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
01549     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
01550     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
01551     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
01552     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
01553     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
01554     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
01555     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
01556     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
01557 }
01558 
01559 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
01560 {
01561     AVCodecContext *avctx = s->avctx;
01562     Mpeg1Context *s1 = (Mpeg1Context*)s;
01563 
01564     /* start frame decoding */
01565     if (s->first_field || s->picture_structure == PICT_FRAME) {
01566         if (MPV_frame_start(s, avctx) < 0)
01567             return -1;
01568 
01569         ff_er_frame_start(s);
01570 
01571         /* first check if we must repeat the frame */
01572         s->current_picture_ptr->f.repeat_pict = 0;
01573         if (s->repeat_first_field) {
01574             if (s->progressive_sequence) {
01575                 if (s->top_field_first)
01576                     s->current_picture_ptr->f.repeat_pict = 4;
01577                 else
01578                     s->current_picture_ptr->f.repeat_pict = 2;
01579             } else if (s->progressive_frame) {
01580                 s->current_picture_ptr->f.repeat_pict = 1;
01581             }
01582         }
01583 
01584         *s->current_picture_ptr->f.pan_scan = s1->pan_scan;
01585 
01586         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
01587             ff_thread_finish_setup(avctx);
01588     } else { // second field
01589         int i;
01590 
01591         if (!s->current_picture_ptr) {
01592             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
01593             return -1;
01594         }
01595 
01596         for (i = 0; i < 4; i++) {
01597             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
01598             if (s->picture_structure == PICT_BOTTOM_FIELD) {
01599                 s->current_picture.f.data[i] += s->current_picture_ptr->f.linesize[i];
01600             }
01601         }
01602     }
01603 
01604     if (avctx->hwaccel) {
01605         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
01606             return -1;
01607     }
01608 
01609 // MPV_frame_start will call this function too,
01610 // but we need to call it on every field
01611     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
01612         if (ff_xvmc_field_start(s, avctx) < 0)
01613             return -1;
01614 
01615     return 0;
01616 }
01617 
01618 #define DECODE_SLICE_ERROR -1
01619 #define DECODE_SLICE_OK     0
01620 
01627 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
01628                              const uint8_t **buf, int buf_size)
01629 {
01630     AVCodecContext *avctx = s->avctx;
01631     const int lowres      = s->avctx->lowres;
01632     const int field_pic   = s->picture_structure != PICT_FRAME;
01633 
01634     s->resync_mb_x =
01635     s->resync_mb_y = -1;
01636 
01637     assert(mb_y < s->mb_height);
01638 
01639     init_get_bits(&s->gb, *buf, buf_size * 8);
01640 
01641     ff_mpeg1_clean_buffers(s);
01642     s->interlaced_dct = 0;
01643 
01644     s->qscale = get_qscale(s);
01645 
01646     if (s->qscale == 0) {
01647         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
01648         return -1;
01649     }
01650 
01651     /* extra slice info */
01652     while (get_bits1(&s->gb) != 0) {
01653         skip_bits(&s->gb, 8);
01654     }
01655 
01656     s->mb_x = 0;
01657 
01658     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
01659         skip_bits1(&s->gb);
01660     } else {
01661         while (get_bits_left(&s->gb) > 0) {
01662             int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
01663             if (code < 0) {
01664                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
01665                 return -1;
01666             }
01667             if (code >= 33) {
01668                 if (code == 33) {
01669                     s->mb_x += 33;
01670                 }
01671                 /* otherwise, stuffing, nothing to do */
01672             } else {
01673                 s->mb_x += code;
01674                 break;
01675             }
01676         }
01677     }
01678 
01679     if (s->mb_x >= (unsigned)s->mb_width) {
01680         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
01681         return -1;
01682     }
01683 
01684     if (avctx->hwaccel) {
01685         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
01686         int start_code = -1;
01687         buf_end = avpriv_mpv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
01688         if (buf_end < *buf + buf_size)
01689             buf_end -= 4;
01690         s->mb_y = mb_y;
01691         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
01692             return DECODE_SLICE_ERROR;
01693         *buf = buf_end;
01694         return DECODE_SLICE_OK;
01695     }
01696 
01697     s->resync_mb_x = s->mb_x;
01698     s->resync_mb_y = s->mb_y = mb_y;
01699     s->mb_skip_run = 0;
01700     ff_init_block_index(s);
01701 
01702     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
01703         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
01704              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",
01705                     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],
01706                     s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
01707                     s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
01708                     s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
01709                     s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
01710         }
01711     }
01712 
01713     for (;;) {
01714         // If 1, we memcpy blocks in xvmcvideo.
01715         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
01716             ff_xvmc_init_block(s); // set s->block
01717 
01718         if (mpeg_decode_mb(s, s->block) < 0)
01719             return -1;
01720 
01721         if (s->current_picture.f.motion_val[0] && !s->encoding) { // note motion_val is normally NULL unless we want to extract the MVs
01722             const int wrap = s->b8_stride;
01723             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
01724             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
01725             int motion_x, motion_y, dir, i;
01726 
01727             for (i = 0; i < 2; i++) {
01728                 for (dir = 0; dir < 2; dir++) {
01729                     if (s->mb_intra || (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
01730                         motion_x = motion_y = 0;
01731                     } else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)) {
01732                         motion_x = s->mv[dir][0][0];
01733                         motion_y = s->mv[dir][0][1];
01734                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
01735                         motion_x = s->mv[dir][i][0];
01736                         motion_y = s->mv[dir][i][1];
01737                     }
01738 
01739                     s->current_picture.f.motion_val[dir][xy    ][0] = motion_x;
01740                     s->current_picture.f.motion_val[dir][xy    ][1] = motion_y;
01741                     s->current_picture.f.motion_val[dir][xy + 1][0] = motion_x;
01742                     s->current_picture.f.motion_val[dir][xy + 1][1] = motion_y;
01743                     s->current_picture.f.ref_index [dir][b8_xy    ] =
01744                     s->current_picture.f.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
01745                     assert(s->field_select[dir][i] == 0 || s->field_select[dir][i] == 1);
01746                 }
01747                 xy += wrap;
01748                 b8_xy +=2;
01749             }
01750         }
01751 
01752         s->dest[0] += 16 >> lowres;
01753         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
01754         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
01755 
01756         MPV_decode_mb(s, s->block);
01757 
01758         if (++s->mb_x >= s->mb_width) {
01759             const int mb_size = 16 >> s->avctx->lowres;
01760 
01761             ff_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
01762             MPV_report_decode_progress(s);
01763 
01764             s->mb_x = 0;
01765             s->mb_y += 1 << field_pic;
01766 
01767             if (s->mb_y >= s->mb_height) {
01768                 int left   = get_bits_left(&s->gb);
01769                 int is_d10 = s->chroma_format == 2 && s->pict_type == AV_PICTURE_TYPE_I && avctx->profile == 0 && avctx->level == 5
01770                              && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
01771                              && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
01772 
01773                 if (left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
01774                     || ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
01775                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
01776                     return -1;
01777                 } else
01778                     goto eos;
01779             }
01780 
01781             ff_init_block_index(s);
01782         }
01783 
01784         /* skip mb handling */
01785         if (s->mb_skip_run == -1) {
01786             /* read increment again */
01787             s->mb_skip_run = 0;
01788             for (;;) {
01789                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
01790                 if (code < 0) {
01791                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
01792                     return -1;
01793                 }
01794                 if (code >= 33) {
01795                     if (code == 33) {
01796                         s->mb_skip_run += 33;
01797                     } else if (code == 35) {
01798                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
01799                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
01800                             return -1;
01801                         }
01802                         goto eos; /* end of slice */
01803                     }
01804                     /* otherwise, stuffing, nothing to do */
01805                 } else {
01806                     s->mb_skip_run += code;
01807                     break;
01808                 }
01809             }
01810             if (s->mb_skip_run) {
01811                 int i;
01812                 if (s->pict_type == AV_PICTURE_TYPE_I) {
01813                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
01814                     return -1;
01815                 }
01816 
01817                 /* skip mb */
01818                 s->mb_intra = 0;
01819                 for (i = 0; i < 12; i++)
01820                     s->block_last_index[i] = -1;
01821                 if (s->picture_structure == PICT_FRAME)
01822                     s->mv_type = MV_TYPE_16X16;
01823                 else
01824                     s->mv_type = MV_TYPE_FIELD;
01825                 if (s->pict_type == AV_PICTURE_TYPE_P) {
01826                     /* if P type, zero motion vector is implied */
01827                     s->mv_dir             = MV_DIR_FORWARD;
01828                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
01829                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
01830                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
01831                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
01832                 } else {
01833                     /* if B type, reuse previous vectors and directions */
01834                     s->mv[0][0][0] = s->last_mv[0][0][0];
01835                     s->mv[0][0][1] = s->last_mv[0][0][1];
01836                     s->mv[1][0][0] = s->last_mv[1][0][0];
01837                     s->mv[1][0][1] = s->last_mv[1][0][1];
01838                 }
01839             }
01840         }
01841     }
01842 eos: // end of slice
01843     *buf += (get_bits_count(&s->gb)-1)/8;
01844 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
01845     return 0;
01846 }
01847 
01848 static int slice_decode_thread(AVCodecContext *c, void *arg)
01849 {
01850     MpegEncContext *s   = *(void**)arg;
01851     const uint8_t *buf  = s->gb.buffer;
01852     int mb_y            = s->start_mb_y;
01853     const int field_pic = s->picture_structure != PICT_FRAME;
01854 
01855     s->error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
01856 
01857     for (;;) {
01858         uint32_t start_code;
01859         int ret;
01860 
01861         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
01862         emms_c();
01863 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
01864 //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);
01865         if (ret < 0) {
01866             if (c->err_recognition & AV_EF_EXPLODE)
01867                 return ret;
01868             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
01869                 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
01870         } else {
01871             ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
01872         }
01873 
01874         if (s->mb_y == s->end_mb_y)
01875             return 0;
01876 
01877         start_code = -1;
01878         buf = avpriv_mpv_find_start_code(buf, s->gb.buffer_end, &start_code);
01879         mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
01880         if (s->picture_structure == PICT_BOTTOM_FIELD)
01881             mb_y++;
01882         if (mb_y < 0 || mb_y >= s->end_mb_y)
01883             return -1;
01884     }
01885 }
01886 
01891 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
01892 {
01893     Mpeg1Context *s1 = avctx->priv_data;
01894     MpegEncContext *s = &s1->mpeg_enc_ctx;
01895 
01896     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
01897         return 0;
01898 
01899     if (s->avctx->hwaccel) {
01900         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
01901             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
01902     }
01903 
01904     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
01905         ff_xvmc_field_end(s);
01906 
01907     /* end of slice reached */
01908     if (/*s->mb_y << field_pic == s->mb_height &&*/ !s->first_field) {
01909         /* end of image */
01910 
01911         s->current_picture_ptr->f.qscale_type = FF_QSCALE_TYPE_MPEG2;
01912 
01913         ff_er_frame_end(s);
01914 
01915         MPV_frame_end(s);
01916 
01917         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
01918             *pict = *(AVFrame*)s->current_picture_ptr;
01919             ff_print_debug_info(s, pict);
01920         } else {
01921             if (avctx->active_thread_type & FF_THREAD_FRAME)
01922                 s->picture_number++;
01923             /* latency of 1 frame for I- and P-frames */
01924             /* XXX: use another variable than picture_number */
01925             if (s->last_picture_ptr != NULL) {
01926                 *pict = *(AVFrame*)s->last_picture_ptr;
01927                  ff_print_debug_info(s, pict);
01928             }
01929         }
01930 
01931         return 1;
01932     } else {
01933         return 0;
01934     }
01935 }
01936 
01937 static int mpeg1_decode_sequence(AVCodecContext *avctx,
01938                                  const uint8_t *buf, int buf_size)
01939 {
01940     Mpeg1Context *s1 = avctx->priv_data;
01941     MpegEncContext *s = &s1->mpeg_enc_ctx;
01942     int width, height;
01943     int i, v, j;
01944 
01945     init_get_bits(&s->gb, buf, buf_size*8);
01946 
01947     width  = get_bits(&s->gb, 12);
01948     height = get_bits(&s->gb, 12);
01949     if (width <= 0 || height <= 0)
01950         return -1;
01951     s->aspect_ratio_info = get_bits(&s->gb, 4);
01952     if (s->aspect_ratio_info == 0) {
01953         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
01954         if (avctx->err_recognition & AV_EF_BITSTREAM)
01955             return -1;
01956     }
01957     s->frame_rate_index = get_bits(&s->gb, 4);
01958     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
01959         return -1;
01960     s->bit_rate = get_bits(&s->gb, 18) * 400;
01961     if (get_bits1(&s->gb) == 0) /* marker */
01962         return -1;
01963     s->width  = width;
01964     s->height = height;
01965 
01966     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
01967     skip_bits(&s->gb, 1);
01968 
01969     /* get matrix */
01970     if (get_bits1(&s->gb)) {
01971         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
01972     } else {
01973         for (i = 0; i < 64; i++) {
01974             j = s->dsp.idct_permutation[i];
01975             v = ff_mpeg1_default_intra_matrix[i];
01976             s->intra_matrix[j]        = v;
01977             s->chroma_intra_matrix[j] = v;
01978         }
01979     }
01980     if (get_bits1(&s->gb)) {
01981         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
01982     } else {
01983         for (i = 0; i < 64; i++) {
01984             int j = s->dsp.idct_permutation[i];
01985             v = ff_mpeg1_default_non_intra_matrix[i];
01986             s->inter_matrix[j]        = v;
01987             s->chroma_inter_matrix[j] = v;
01988         }
01989     }
01990 
01991     if (show_bits(&s->gb, 23) != 0) {
01992         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
01993         return -1;
01994     }
01995 
01996     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
01997     s->progressive_sequence = 1;
01998     s->progressive_frame    = 1;
01999     s->picture_structure    = PICT_FRAME;
02000     s->frame_pred_frame_dct = 1;
02001     s->chroma_format        = 1;
02002     s->codec_id             = s->avctx->codec_id = CODEC_ID_MPEG1VIDEO;
02003     avctx->sub_id           = 1; /* indicates MPEG-1 */
02004     s->out_format           = FMT_MPEG1;
02005     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
02006     if (s->flags & CODEC_FLAG_LOW_DELAY)
02007         s->low_delay = 1;
02008 
02009     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
02010         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
02011                s->avctx->rc_buffer_size, s->bit_rate);
02012 
02013     return 0;
02014 }
02015 
02016 static int vcr2_init_sequence(AVCodecContext *avctx)
02017 {
02018     Mpeg1Context *s1 = avctx->priv_data;
02019     MpegEncContext *s = &s1->mpeg_enc_ctx;
02020     int i, v;
02021 
02022     /* start new MPEG-1 context decoding */
02023     s->out_format = FMT_MPEG1;
02024     if (s1->mpeg_enc_ctx_allocated) {
02025         MPV_common_end(s);
02026     }
02027     s->width  = avctx->coded_width;
02028     s->height = avctx->coded_height;
02029     avctx->has_b_frames = 0; // true?
02030     s->low_delay = 1;
02031 
02032     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
02033     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
02034 
02035     if (avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
02036         s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
02037         if (avctx->idct_algo == FF_IDCT_AUTO)
02038             avctx->idct_algo = FF_IDCT_SIMPLE;
02039 
02040     if (MPV_common_init(s) < 0)
02041         return -1;
02042     exchange_uv(s); // common init reset pblocks, so we swap them here
02043     s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
02044     s1->mpeg_enc_ctx_allocated = 1;
02045 
02046     for (i = 0; i < 64; i++) {
02047         int j = s->dsp.idct_permutation[i];
02048         v = ff_mpeg1_default_intra_matrix[i];
02049         s->intra_matrix[j]        = v;
02050         s->chroma_intra_matrix[j] = v;
02051 
02052         v = ff_mpeg1_default_non_intra_matrix[i];
02053         s->inter_matrix[j]        = v;
02054         s->chroma_inter_matrix[j] = v;
02055     }
02056 
02057     s->progressive_sequence  = 1;
02058     s->progressive_frame     = 1;
02059     s->picture_structure     = PICT_FRAME;
02060     s->frame_pred_frame_dct  = 1;
02061     s->chroma_format         = 1;
02062     s->codec_id              = s->avctx->codec_id = CODEC_ID_MPEG2VIDEO;
02063     avctx->sub_id            = 2; /* indicates MPEG-2 */
02064     s1->save_width           = s->width;
02065     s1->save_height          = s->height;
02066     s1->save_progressive_seq = s->progressive_sequence;
02067     return 0;
02068 }
02069 
02070 
02071 static void mpeg_decode_user_data(AVCodecContext *avctx,
02072                                   const uint8_t *p, int buf_size)
02073 {
02074     const uint8_t *buf_end = p + buf_size;
02075 
02076     /* we parse the DTG active format information */
02077     if (buf_end - p >= 5 &&
02078         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
02079         int flags = p[4];
02080         p += 5;
02081         if (flags & 0x80) {
02082             /* skip event id */
02083             p += 2;
02084         }
02085         if (flags & 0x40) {
02086             if (buf_end - p < 1)
02087                 return;
02088             avctx->dtg_active_format = p[0] & 0x0f;
02089         }
02090     }
02091 }
02092 
02093 static void mpeg_decode_gop(AVCodecContext *avctx,
02094                             const uint8_t *buf, int buf_size)
02095 {
02096     Mpeg1Context *s1  = avctx->priv_data;
02097     MpegEncContext *s = &s1->mpeg_enc_ctx;
02098 
02099     int time_code_hours, time_code_minutes;
02100     int time_code_seconds, time_code_pictures;
02101     int broken_link;
02102 
02103     init_get_bits(&s->gb, buf, buf_size*8);
02104 
02105     skip_bits1(&s->gb); /* drop_frame_flag */
02106 
02107     time_code_hours   = get_bits(&s->gb, 5);
02108     time_code_minutes = get_bits(&s->gb, 6);
02109     skip_bits1(&s->gb); // marker bit
02110     time_code_seconds  = get_bits(&s->gb, 6);
02111     time_code_pictures = get_bits(&s->gb, 6);
02112 
02113     s1->closed_gop = get_bits1(&s->gb);
02114     /*broken_link indicate that after editing the
02115       reference frames of the first B-Frames after GOP I-Frame
02116       are missing (open gop)*/
02117     broken_link = get_bits1(&s->gb);
02118 
02119     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
02120         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
02121                time_code_hours, time_code_minutes, time_code_seconds,
02122                time_code_pictures, s1->closed_gop, broken_link);
02123 }
02128 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
02129 {
02130     int i;
02131     uint32_t state = pc->state;
02132 
02133     /* EOF considered as end of frame */
02134     if (buf_size == 0)
02135         return 0;
02136 
02137 /*
02138  0  frame start         -> 1/4
02139  1  first_SEQEXT        -> 0/2
02140  2  first field start   -> 3/0
02141  3  second_SEQEXT       -> 2/0
02142  4  searching end
02143 */
02144 
02145     for (i = 0; i < buf_size; i++) {
02146         assert(pc->frame_start_found >= 0 && pc->frame_start_found <= 4);
02147         if (pc->frame_start_found & 1) {
02148             if (state == EXT_START_CODE && (buf[i] & 0xF0) != 0x80)
02149                 pc->frame_start_found--;
02150             else if (state == EXT_START_CODE + 2) {
02151                 if ((buf[i] & 3) == 3)
02152                     pc->frame_start_found = 0;
02153                 else
02154                     pc->frame_start_found = (pc->frame_start_found + 1) & 3;
02155             }
02156             state++;
02157         } else {
02158             i = avpriv_mpv_find_start_code(buf + i, buf + buf_size, &state) - buf - 1;
02159             if (pc->frame_start_found == 0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE) {
02160                 i++;
02161                 pc->frame_start_found = 4;
02162             }
02163             if (state == SEQ_END_CODE) {
02164                 pc->state=-1;
02165                 return i+1;
02166             }
02167             if (pc->frame_start_found == 2 && state == SEQ_START_CODE)
02168                 pc->frame_start_found = 0;
02169             if (pc->frame_start_found  < 4 && state == EXT_START_CODE)
02170                 pc->frame_start_found++;
02171             if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) {
02172                 if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) {
02173                     pc->frame_start_found = 0;
02174                     pc->state             = -1;
02175                     return i - 3;
02176                 }
02177             }
02178             if (pc->frame_start_found == 0 && s && state == PICTURE_START_CODE) {
02179                 ff_fetch_timestamp(s, i - 3, 1);
02180             }
02181         }
02182     }
02183     pc->state = state;
02184     return END_NOT_FOUND;
02185 }
02186 
02187 static int decode_chunks(AVCodecContext *avctx,
02188                          AVFrame *picture, int *data_size,
02189                          const uint8_t *buf, int buf_size);
02190 
02191 /* handle buffering and image synchronisation */
02192 static int mpeg_decode_frame(AVCodecContext *avctx,
02193                              void *data, int *data_size,
02194                              AVPacket *avpkt)
02195 {
02196     const uint8_t *buf = avpkt->data;
02197     int buf_size = avpkt->size;
02198     Mpeg1Context *s = avctx->priv_data;
02199     AVFrame *picture = data;
02200     MpegEncContext *s2 = &s->mpeg_enc_ctx;
02201     av_dlog(avctx, "fill_buffer\n");
02202 
02203     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
02204         /* special case for last picture */
02205         if (s2->low_delay == 0 && s2->next_picture_ptr) {
02206             *picture = *(AVFrame*)s2->next_picture_ptr;
02207             s2->next_picture_ptr = NULL;
02208 
02209             *data_size = sizeof(AVFrame);
02210         }
02211         return buf_size;
02212     }
02213 
02214     if (s2->flags & CODEC_FLAG_TRUNCATED) {
02215         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
02216 
02217         if (ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0)
02218             return buf_size;
02219     }
02220 
02221     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
02222         vcr2_init_sequence(avctx);
02223 
02224     s->slice_count = 0;
02225 
02226     if (avctx->extradata && !avctx->frame_number) {
02227         int ret = decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
02228         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
02229             return ret;
02230     }
02231 
02232     return decode_chunks(avctx, picture, data_size, buf, buf_size);
02233 }
02234 
02235 static int decode_chunks(AVCodecContext *avctx,
02236                          AVFrame *picture, int *data_size,
02237                          const uint8_t *buf, int buf_size)
02238 {
02239     Mpeg1Context *s = avctx->priv_data;
02240     MpegEncContext *s2 = &s->mpeg_enc_ctx;
02241     const uint8_t *buf_ptr = buf;
02242     const uint8_t *buf_end = buf + buf_size;
02243     int ret, input_size;
02244     int last_code = 0;
02245 
02246     for (;;) {
02247         /* find next start code */
02248         uint32_t start_code = -1;
02249         buf_ptr = avpriv_mpv_find_start_code(buf_ptr, buf_end, &start_code);
02250         if (start_code > 0x1ff) {
02251             if (s2->pict_type != AV_PICTURE_TYPE_B || avctx->skip_frame <= AVDISCARD_DEFAULT) {
02252                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
02253                     int i;
02254 
02255                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
02256                     for (i = 0; i < s->slice_count; i++)
02257                         s2->error_count += s2->thread_context[i]->error_count;
02258                 }
02259 
02260                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
02261                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
02262 
02263                 if (slice_end(avctx, picture)) {
02264                     if (s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
02265                         *data_size = sizeof(AVPicture);
02266                 }
02267             }
02268             s2->pict_type = 0;
02269             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
02270         }
02271 
02272         input_size = buf_end - buf_ptr;
02273 
02274         if (avctx->debug & FF_DEBUG_STARTCODE) {
02275             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
02276         }
02277 
02278         /* prepare data for next start code */
02279         switch (start_code) {
02280         case SEQ_START_CODE:
02281             if (last_code == 0) {
02282                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
02283                 s->sync=1;
02284             } else {
02285                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
02286                 if (avctx->err_recognition & AV_EF_EXPLODE)
02287                     return AVERROR_INVALIDDATA;
02288             }
02289             break;
02290 
02291         case PICTURE_START_CODE:
02292             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && s->slice_count) {
02293                 int i;
02294 
02295                 avctx->execute(avctx, slice_decode_thread,
02296                                s2->thread_context, NULL,
02297                                s->slice_count, sizeof(void*));
02298                 for (i = 0; i < s->slice_count; i++)
02299                     s2->error_count += s2->thread_context[i]->error_count;
02300                 s->slice_count = 0;
02301             }
02302             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
02303                 ret = mpeg_decode_postinit(avctx);
02304                 if (ret < 0) {
02305                     av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
02306                     return ret;
02307                 }
02308 
02309                 /* we have a complete image: we try to decompress it */
02310                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
02311                     s2->pict_type = 0;
02312                 s2->first_slice = 1;
02313                 last_code = PICTURE_START_CODE;
02314             } else {
02315                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
02316                 if (avctx->err_recognition & AV_EF_EXPLODE)
02317                     return AVERROR_INVALIDDATA;
02318             }
02319             break;
02320         case EXT_START_CODE:
02321             init_get_bits(&s2->gb, buf_ptr, input_size*8);
02322 
02323             switch (get_bits(&s2->gb, 4)) {
02324             case 0x1:
02325                 if (last_code == 0) {
02326                 mpeg_decode_sequence_extension(s);
02327                 } else {
02328                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
02329                     if (avctx->err_recognition & AV_EF_EXPLODE)
02330                         return AVERROR_INVALIDDATA;
02331                 }
02332                 break;
02333             case 0x2:
02334                 mpeg_decode_sequence_display_extension(s);
02335                 break;
02336             case 0x3:
02337                 mpeg_decode_quant_matrix_extension(s2);
02338                 break;
02339             case 0x7:
02340                 mpeg_decode_picture_display_extension(s);
02341                 break;
02342             case 0x8:
02343                 if (last_code == PICTURE_START_CODE) {
02344                     mpeg_decode_picture_coding_extension(s);
02345                 } else {
02346                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
02347                     if (avctx->err_recognition & AV_EF_EXPLODE)
02348                         return AVERROR_INVALIDDATA;
02349                 }
02350                 break;
02351             }
02352             break;
02353         case USER_START_CODE:
02354             mpeg_decode_user_data(avctx, buf_ptr, input_size);
02355             break;
02356         case GOP_START_CODE:
02357             if (last_code == 0) {
02358                 s2->first_field=0;
02359                 mpeg_decode_gop(avctx, buf_ptr, input_size);
02360                 s->sync=1;
02361             } else {
02362                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
02363                 if (avctx->err_recognition & AV_EF_EXPLODE)
02364                     return AVERROR_INVALIDDATA;
02365             }
02366             break;
02367         default:
02368             if (start_code >= SLICE_MIN_START_CODE &&
02369                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
02370                 const int field_pic = s2->picture_structure != PICT_FRAME;
02371                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
02372                 last_code = SLICE_MIN_START_CODE;
02373 
02374                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
02375                     mb_y++;
02376 
02377                 if (mb_y >= s2->mb_height) {
02378                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
02379                     return -1;
02380                 }
02381 
02382                 if (s2->last_picture_ptr == NULL) {
02383                 /* Skip B-frames if we do not have reference frames and gop is not closed */
02384                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
02385                         if (!s->closed_gop)
02386                             break;
02387                     }
02388                 }
02389                 if (s2->pict_type == AV_PICTURE_TYPE_I)
02390                     s->sync=1;
02391                 if (s2->next_picture_ptr == NULL) {
02392                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
02393                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) break;
02394                 }
02395                 if ((avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type == AV_PICTURE_TYPE_B) ||
02396                     (avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type != AV_PICTURE_TYPE_I) ||
02397                      avctx->skip_frame >= AVDISCARD_ALL)
02398                     break;
02399 
02400                 if (!s->mpeg_enc_ctx_allocated)
02401                     break;
02402 
02403                 if (s2->codec_id == CODEC_ID_MPEG2VIDEO) {
02404                     if (mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
02405                         break;
02406                 }
02407 
02408                 if (!s2->pict_type) {
02409                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
02410                     if (avctx->err_recognition & AV_EF_EXPLODE)
02411                         return AVERROR_INVALIDDATA;
02412                     break;
02413                 }
02414 
02415                 if (s2->first_slice) {
02416                     s2->first_slice = 0;
02417                     if (mpeg_field_start(s2, buf, buf_size) < 0)
02418                         return -1;
02419                 }
02420                 if (!s2->current_picture_ptr) {
02421                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
02422                     return AVERROR_INVALIDDATA;
02423                 }
02424 
02425                 if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
02426                     s->slice_count++;
02427                     break;
02428                 }
02429 
02430                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
02431                     int threshold = (s2->mb_height * s->slice_count +
02432                                      s2->slice_context_count / 2) /
02433                                     s2->slice_context_count;
02434                     if (threshold <= mb_y) {
02435                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
02436 
02437                         thread_context->start_mb_y = mb_y;
02438                         thread_context->end_mb_y   = s2->mb_height;
02439                         if (s->slice_count) {
02440                             s2->thread_context[s->slice_count-1]->end_mb_y = mb_y;
02441                             ff_update_duplicate_context(thread_context, s2);
02442                         }
02443                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
02444                         s->slice_count++;
02445                     }
02446                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
02447                 } else {
02448                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
02449                     emms_c();
02450 
02451                     if (ret < 0) {
02452                         if (avctx->err_recognition & AV_EF_EXPLODE)
02453                             return ret;
02454                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
02455                             ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
02456                     } else {
02457                         ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
02458                     }
02459                 }
02460             }
02461             break;
02462         }
02463     }
02464 }
02465 
02466 static void flush(AVCodecContext *avctx)
02467 {
02468     Mpeg1Context *s = avctx->priv_data;
02469 
02470     s->sync=0;
02471     s->closed_gop = 0;
02472 
02473     ff_mpeg_flush(avctx);
02474 }
02475 
02476 static int mpeg_decode_end(AVCodecContext *avctx)
02477 {
02478     Mpeg1Context *s = avctx->priv_data;
02479 
02480     if (s->mpeg_enc_ctx_allocated)
02481         MPV_common_end(&s->mpeg_enc_ctx);
02482     return 0;
02483 }
02484 
02485 static const AVProfile mpeg2_video_profiles[] = {
02486     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
02487     { FF_PROFILE_MPEG2_HIGH,         "High"               },
02488     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
02489     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
02490     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
02491     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
02492     { FF_PROFILE_RESERVED,           "Reserved"           },
02493     { FF_PROFILE_RESERVED,           "Reserved"           },
02494     { FF_PROFILE_UNKNOWN },
02495 };
02496 
02497 
02498 AVCodec ff_mpeg1video_decoder = {
02499     .name           = "mpeg1video",
02500     .type           = AVMEDIA_TYPE_VIDEO,
02501     .id             = CODEC_ID_MPEG1VIDEO,
02502     .priv_data_size = sizeof(Mpeg1Context),
02503     .init           = mpeg_decode_init,
02504     .close          = mpeg_decode_end,
02505     .decode         = mpeg_decode_frame,
02506     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
02507     .flush          = flush,
02508     .max_lowres     = 3,
02509     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
02510     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
02511 };
02512 
02513 AVCodec ff_mpeg2video_decoder = {
02514     .name           = "mpeg2video",
02515     .type           = AVMEDIA_TYPE_VIDEO,
02516     .id             = CODEC_ID_MPEG2VIDEO,
02517     .priv_data_size = sizeof(Mpeg1Context),
02518     .init           = mpeg_decode_init,
02519     .close          = mpeg_decode_end,
02520     .decode         = mpeg_decode_frame,
02521     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
02522     .flush          = flush,
02523     .max_lowres     = 3,
02524     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
02525     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
02526 };
02527 
02528 #if CONFIG_MPEG_XVMC_DECODER
02529 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
02530 {
02531     if (avctx->active_thread_type & FF_THREAD_SLICE)
02532         return -1;
02533     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
02534         return -1;
02535     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
02536         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
02537     }
02538     mpeg_decode_init(avctx);
02539 
02540     avctx->pix_fmt           = PIX_FMT_XVMC_MPEG2_IDCT;
02541     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
02542 
02543     return 0;
02544 }
02545 
02546 AVCodec ff_mpeg_xvmc_decoder = {
02547     .name           = "mpegvideo_xvmc",
02548     .type           = AVMEDIA_TYPE_VIDEO,
02549     .id             = CODEC_ID_MPEG2VIDEO_XVMC,
02550     .priv_data_size = sizeof(Mpeg1Context),
02551     .init           = mpeg_mc_decode_init,
02552     .close          = mpeg_decode_end,
02553     .decode         = mpeg_decode_frame,
02554     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
02555     .flush          = flush,
02556     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
02557 };
02558 
02559 #endif
02560 
02561 #if CONFIG_MPEG_VDPAU_DECODER
02562 AVCodec ff_mpeg_vdpau_decoder = {
02563     .name           = "mpegvideo_vdpau",
02564     .type           = AVMEDIA_TYPE_VIDEO,
02565     .id             = CODEC_ID_MPEG2VIDEO,
02566     .priv_data_size = sizeof(Mpeg1Context),
02567     .init           = mpeg_decode_init,
02568     .close          = mpeg_decode_end,
02569     .decode         = mpeg_decode_frame,
02570     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
02571     .flush          = flush,
02572     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
02573 };
02574 #endif
02575 
02576 #if CONFIG_MPEG1_VDPAU_DECODER
02577 AVCodec ff_mpeg1_vdpau_decoder = {
02578     .name           = "mpeg1video_vdpau",
02579     .type           = AVMEDIA_TYPE_VIDEO,
02580     .id             = CODEC_ID_MPEG1VIDEO,
02581     .priv_data_size = sizeof(Mpeg1Context),
02582     .init           = mpeg_decode_init,
02583     .close          = mpeg_decode_end,
02584     .decode         = mpeg_decode_frame,
02585     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
02586     .flush          = flush,
02587     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
02588 };
02589 #endif
02590 
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