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 #define check_scantable_index(ctx, x)                                     \
00084     do {                                                                  \
00085         if ((x) > 63) {                                                   \
00086             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", \
00087                    ctx->mb_x, ctx->mb_y);                                 \
00088             return AVERROR_INVALIDDATA;                                   \
00089         }                                                                 \
00090     } while (0)                                                           \
00091 
00092 static inline int mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00093 {
00094     int level, dc, diff, i, j, run;
00095     int component;
00096     RLTable *rl = &ff_rl_mpeg1;
00097     uint8_t * const scantable    = s->intra_scantable.permutated;
00098     const uint16_t *quant_matrix = s->intra_matrix;
00099     const int qscale             = s->qscale;
00100 
00101     /* DC coefficient */
00102     component = (n <= 3 ? 0 : n - 4 + 1);
00103     diff = decode_dc(&s->gb, component);
00104     if (diff >= 0xffff)
00105         return -1;
00106     dc  = s->last_dc[component];
00107     dc += diff;
00108     s->last_dc[component] = dc;
00109     block[0] = dc * quant_matrix[0];
00110     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
00111     i = 0;
00112     {
00113         OPEN_READER(re, &s->gb);
00114         /* now quantify & encode AC coefficients */
00115         for (;;) {
00116             UPDATE_CACHE(re, &s->gb);
00117             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00118 
00119             if (level == 127) {
00120                 break;
00121             } else if (level != 0) {
00122                 i += run;
00123                 check_scantable_index(s, i);
00124                 j = scantable[i];
00125                 level = (level * qscale * quant_matrix[j]) >> 4;
00126                 level = (level - 1) | 1;
00127                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00128                 LAST_SKIP_BITS(re, &s->gb, 1);
00129             } else {
00130                 /* escape */
00131                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00132                 UPDATE_CACHE(re, &s->gb);
00133                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00134                 if (level == -128) {
00135                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
00136                 } else if (level == 0) {
00137                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
00138                 }
00139                 i += run;
00140                 check_scantable_index(s, i);
00141                 j = scantable[i];
00142                 if (level < 0) {
00143                     level = -level;
00144                     level = (level * qscale * quant_matrix[j]) >> 4;
00145                     level = (level - 1) | 1;
00146                     level = -level;
00147                 } else {
00148                     level = (level * qscale * quant_matrix[j]) >> 4;
00149                     level = (level - 1) | 1;
00150                 }
00151             }
00152 
00153             block[j] = level;
00154         }
00155         CLOSE_READER(re, &s->gb);
00156     }
00157     s->block_last_index[n] = i;
00158    return 0;
00159 }
00160 
00161 int ff_mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00162 {
00163     return mpeg1_decode_block_intra(s, block, n);
00164 }
00165 
00166 static inline int mpeg1_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
00167 {
00168     int level, i, j, run;
00169     RLTable *rl = &ff_rl_mpeg1;
00170     uint8_t * const scantable    = s->intra_scantable.permutated;
00171     const uint16_t *quant_matrix = s->inter_matrix;
00172     const int qscale             = s->qscale;
00173 
00174     {
00175         OPEN_READER(re, &s->gb);
00176         i = -1;
00177         // special case for first coefficient, no need to add second VLC table
00178         UPDATE_CACHE(re, &s->gb);
00179         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00180             level = (3 * qscale * quant_matrix[0]) >> 5;
00181             level = (level - 1) | 1;
00182             if (GET_CACHE(re, &s->gb) & 0x40000000)
00183                 level = -level;
00184             block[0] = level;
00185             i++;
00186             SKIP_BITS(re, &s->gb, 2);
00187             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00188                 goto end;
00189         }
00190         /* now quantify & encode AC coefficients */
00191         for (;;) {
00192             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00193 
00194             if (level != 0) {
00195                 i += run;
00196                 j = scantable[i];
00197                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00198                 level = (level - 1) | 1;
00199                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00200                 SKIP_BITS(re, &s->gb, 1);
00201             } else {
00202                 /* escape */
00203                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00204                 UPDATE_CACHE(re, &s->gb);
00205                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00206                 if (level == -128) {
00207                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
00208                 } else if (level == 0) {
00209                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
00210                 }
00211                 i += run;
00212                 j = scantable[i];
00213                 if (level < 0) {
00214                     level = -level;
00215                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00216                     level = (level - 1) | 1;
00217                     level = -level;
00218                 } else {
00219                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00220                     level = (level - 1) | 1;
00221                 }
00222             }
00223             if (i > 63) {
00224                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
00225                 return -1;
00226             }
00227 
00228             block[j] = level;
00229             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00230                 break;
00231             UPDATE_CACHE(re, &s->gb);
00232         }
00233 end:
00234         LAST_SKIP_BITS(re, &s->gb, 2);
00235         CLOSE_READER(re, &s->gb);
00236     }
00237     s->block_last_index[n] = i;
00238     return 0;
00239 }
00240 
00241 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
00242 {
00243     int level, i, j, run;
00244     RLTable *rl = &ff_rl_mpeg1;
00245     uint8_t * const scantable = s->intra_scantable.permutated;
00246     const int qscale          = s->qscale;
00247 
00248     {
00249         OPEN_READER(re, &s->gb);
00250         i = -1;
00251         // special case for first coefficient, no need to add second VLC table
00252         UPDATE_CACHE(re, &s->gb);
00253         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00254             level = (3 * qscale) >> 1;
00255             level = (level - 1) | 1;
00256             if (GET_CACHE(re, &s->gb) & 0x40000000)
00257                 level = -level;
00258             block[0] = level;
00259             i++;
00260             SKIP_BITS(re, &s->gb, 2);
00261             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00262                 goto end;
00263         }
00264 
00265         /* now quantify & encode AC coefficients */
00266         for (;;) {
00267             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00268 
00269             if (level != 0) {
00270                 i += run;
00271                 check_scantable_index(s, i);
00272                 j = scantable[i];
00273                 level = ((level * 2 + 1) * qscale) >> 1;
00274                 level = (level - 1) | 1;
00275                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00276                 SKIP_BITS(re, &s->gb, 1);
00277             } else {
00278                 /* escape */
00279                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
00280                 UPDATE_CACHE(re, &s->gb);
00281                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
00282                 if (level == -128) {
00283                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
00284                 } else if (level == 0) {
00285                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
00286                 }
00287                 i += run;
00288                 check_scantable_index(s, i);
00289                 j = scantable[i];
00290                 if (level < 0) {
00291                     level = -level;
00292                     level = ((level * 2 + 1) * qscale) >> 1;
00293                     level = (level - 1) | 1;
00294                     level = -level;
00295                 } else {
00296                     level = ((level * 2 + 1) * qscale) >> 1;
00297                     level = (level - 1) | 1;
00298                 }
00299             }
00300 
00301             block[j] = level;
00302             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00303                 break;
00304             UPDATE_CACHE(re, &s->gb);
00305         }
00306 end:
00307         LAST_SKIP_BITS(re, &s->gb, 2);
00308         CLOSE_READER(re, &s->gb);
00309     }
00310     s->block_last_index[n] = i;
00311     return 0;
00312 }
00313 
00314 
00315 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n)
00316 {
00317     int level, i, j, run;
00318     RLTable *rl = &ff_rl_mpeg1;
00319     uint8_t * const scantable = s->intra_scantable.permutated;
00320     const uint16_t *quant_matrix;
00321     const int qscale = s->qscale;
00322     int mismatch;
00323 
00324     mismatch = 1;
00325 
00326     {
00327         OPEN_READER(re, &s->gb);
00328         i = -1;
00329         if (n < 4)
00330             quant_matrix = s->inter_matrix;
00331         else
00332             quant_matrix = s->chroma_inter_matrix;
00333 
00334         // special case for first coefficient, no need to add second VLC table
00335         UPDATE_CACHE(re, &s->gb);
00336         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00337             level= (3 * qscale * quant_matrix[0]) >> 5;
00338             if (GET_CACHE(re, &s->gb) & 0x40000000)
00339                 level = -level;
00340             block[0]  = level;
00341             mismatch ^= level;
00342             i++;
00343             SKIP_BITS(re, &s->gb, 2);
00344             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00345                 goto end;
00346         }
00347 
00348         /* now quantify & encode AC coefficients */
00349         for (;;) {
00350             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00351 
00352             if (level != 0) {
00353                 i += run;
00354                 check_scantable_index(s, i);
00355                 j = scantable[i];
00356                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00357                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00358                 SKIP_BITS(re, &s->gb, 1);
00359             } else {
00360                 /* escape */
00361                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00362                 UPDATE_CACHE(re, &s->gb);
00363                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00364 
00365                 i += run;
00366                 check_scantable_index(s, i);
00367                 j = scantable[i];
00368                 if (level < 0) {
00369                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00370                     level = -level;
00371                 } else {
00372                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
00373                 }
00374             }
00375 
00376             mismatch ^= level;
00377             block[j]  = level;
00378             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00379                 break;
00380             UPDATE_CACHE(re, &s->gb);
00381         }
00382 end:
00383         LAST_SKIP_BITS(re, &s->gb, 2);
00384         CLOSE_READER(re, &s->gb);
00385     }
00386     block[63] ^= (mismatch & 1);
00387 
00388     s->block_last_index[n] = i;
00389     return 0;
00390 }
00391 
00392 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
00393                                                     DCTELEM *block, int n)
00394 {
00395     int level, i, j, run;
00396     RLTable *rl = &ff_rl_mpeg1;
00397     uint8_t * const scantable = s->intra_scantable.permutated;
00398     const int qscale          = s->qscale;
00399     OPEN_READER(re, &s->gb);
00400     i = -1;
00401 
00402     // special case for first coefficient, no need to add second VLC table
00403     UPDATE_CACHE(re, &s->gb);
00404     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
00405         level = (3 * qscale) >> 1;
00406         if (GET_CACHE(re, &s->gb) & 0x40000000)
00407             level = -level;
00408         block[0] = level;
00409         i++;
00410         SKIP_BITS(re, &s->gb, 2);
00411         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00412             goto end;
00413     }
00414 
00415     /* now quantify & encode AC coefficients */
00416     for (;;) {
00417         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00418 
00419         if (level != 0) {
00420             i += run;
00421             check_scantable_index(s, i);
00422             j  = scantable[i];
00423             level = ((level * 2 + 1) * qscale) >> 1;
00424             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00425             SKIP_BITS(re, &s->gb, 1);
00426         } else {
00427             /* escape */
00428             run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00429             UPDATE_CACHE(re, &s->gb);
00430             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00431 
00432             i += run;
00433             check_scantable_index(s, i);
00434             j  = scantable[i];
00435             if (level < 0) {
00436                 level = ((-level * 2 + 1) * qscale) >> 1;
00437                 level = -level;
00438             } else {
00439                 level = ((level * 2 + 1) * qscale) >> 1;
00440             }
00441         }
00442 
00443         block[j] = level;
00444         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
00445             break;
00446         UPDATE_CACHE(re, &s->gb);
00447     }
00448 end:
00449     LAST_SKIP_BITS(re, &s->gb, 2);
00450     CLOSE_READER(re, &s->gb);
00451     s->block_last_index[n] = i;
00452     return 0;
00453 }
00454 
00455 
00456 static inline int mpeg2_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00457 {
00458     int level, dc, diff, i, j, run;
00459     int component;
00460     RLTable *rl;
00461     uint8_t * const scantable = s->intra_scantable.permutated;
00462     const uint16_t *quant_matrix;
00463     const int qscale = s->qscale;
00464     int mismatch;
00465 
00466     /* DC coefficient */
00467     if (n < 4) {
00468         quant_matrix = s->intra_matrix;
00469         component = 0;
00470     } else {
00471         quant_matrix = s->chroma_intra_matrix;
00472         component = (n & 1) + 1;
00473     }
00474     diff = decode_dc(&s->gb, component);
00475     if (diff >= 0xffff)
00476         return -1;
00477     dc  = s->last_dc[component];
00478     dc += diff;
00479     s->last_dc[component] = dc;
00480     block[0] = dc << (3 - s->intra_dc_precision);
00481     av_dlog(s->avctx, "dc=%d\n", block[0]);
00482     mismatch = block[0] ^ 1;
00483     i = 0;
00484     if (s->intra_vlc_format)
00485         rl = &ff_rl_mpeg2;
00486     else
00487         rl = &ff_rl_mpeg1;
00488 
00489     {
00490         OPEN_READER(re, &s->gb);
00491         /* now quantify & encode AC coefficients */
00492         for (;;) {
00493             UPDATE_CACHE(re, &s->gb);
00494             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00495 
00496             if (level == 127) {
00497                 break;
00498             } else if (level != 0) {
00499                 i += run;
00500                 check_scantable_index(s, i);
00501                 j  = scantable[i];
00502                 level = (level * qscale * quant_matrix[j]) >> 4;
00503                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00504                 LAST_SKIP_BITS(re, &s->gb, 1);
00505             } else {
00506                 /* escape */
00507                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00508                 UPDATE_CACHE(re, &s->gb);
00509                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00510                 i += run;
00511                 check_scantable_index(s, i);
00512                 j  = scantable[i];
00513                 if (level < 0) {
00514                     level = (-level * qscale * quant_matrix[j]) >> 4;
00515                     level = -level;
00516                 } else {
00517                     level = (level * qscale * quant_matrix[j]) >> 4;
00518                 }
00519             }
00520 
00521             mismatch ^= level;
00522             block[j]  = level;
00523         }
00524         CLOSE_READER(re, &s->gb);
00525     }
00526     block[63] ^= mismatch & 1;
00527 
00528     s->block_last_index[n] = i;
00529     return 0;
00530 }
00531 
00532 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
00533 {
00534     int level, dc, diff, i, j, run;
00535     int component;
00536     RLTable *rl;
00537     uint8_t * const scantable = s->intra_scantable.permutated;
00538     const uint16_t *quant_matrix;
00539     const int qscale = s->qscale;
00540 
00541     /* DC coefficient */
00542     if (n < 4) {
00543         quant_matrix = s->intra_matrix;
00544         component = 0;
00545     } else {
00546         quant_matrix = s->chroma_intra_matrix;
00547         component = (n & 1) + 1;
00548     }
00549     diff = decode_dc(&s->gb, component);
00550     if (diff >= 0xffff)
00551         return -1;
00552     dc = s->last_dc[component];
00553     dc += diff;
00554     s->last_dc[component] = dc;
00555     block[0] = dc << (3 - s->intra_dc_precision);
00556     i = 0;
00557     if (s->intra_vlc_format)
00558         rl = &ff_rl_mpeg2;
00559     else
00560         rl = &ff_rl_mpeg1;
00561 
00562     {
00563         OPEN_READER(re, &s->gb);
00564         /* now quantify & encode AC coefficients */
00565         for (;;) {
00566             UPDATE_CACHE(re, &s->gb);
00567             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
00568 
00569             if (level == 127) {
00570                 break;
00571             } else if (level != 0) {
00572                 i += run;
00573                 check_scantable_index(s, i);
00574                 j  = scantable[i];
00575                 level = (level * qscale * quant_matrix[j]) >> 4;
00576                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
00577                 LAST_SKIP_BITS(re, &s->gb, 1);
00578             } else {
00579                 /* escape */
00580                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
00581                 UPDATE_CACHE(re, &s->gb);
00582                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
00583                 i += run;
00584                 check_scantable_index(s, i);
00585                 j  = scantable[i];
00586                 if (level < 0) {
00587                     level = (-level * qscale * quant_matrix[j]) >> 4;
00588                     level = -level;
00589                 } else {
00590                     level = (level * qscale * quant_matrix[j]) >> 4;
00591                 }
00592             }
00593 
00594             block[j] = level;
00595         }
00596         CLOSE_READER(re, &s->gb);
00597     }
00598 
00599     s->block_last_index[n] = i;
00600     return 0;
00601 }
00602 
00603 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
00604 
00605 #define INIT_2D_VLC_RL(rl, static_size)\
00606 {\
00607     static RL_VLC_ELEM rl_vlc_table[static_size];\
00608     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
00609                     &rl.table_vlc[0][1], 4, 2,\
00610                     &rl.table_vlc[0][0], 4, 2, static_size);\
00611 \
00612     rl.rl_vlc[0] = rl_vlc_table;\
00613     init_2d_vlc_rl(&rl);\
00614 }
00615 
00616 static void init_2d_vlc_rl(RLTable *rl)
00617 {
00618     int i;
00619 
00620     for (i = 0; i < rl->vlc.table_size; i++) {
00621         int code = rl->vlc.table[i][0];
00622         int len  = rl->vlc.table[i][1];
00623         int level, run;
00624 
00625         if (len == 0) { // illegal code
00626             run   = 65;
00627             level = MAX_LEVEL;
00628         } else if (len<0) { //more bits needed
00629             run   = 0;
00630             level = code;
00631         } else {
00632             if (code == rl->n) { //esc
00633                 run   = 65;
00634                 level = 0;
00635             } else if (code == rl->n+1) { //eob
00636                 run   = 0;
00637                 level = 127;
00638             } else {
00639                 run   = rl->table_run  [code] + 1;
00640                 level = rl->table_level[code];
00641             }
00642         }
00643         rl->rl_vlc[0][i].len   = len;
00644         rl->rl_vlc[0][i].level = level;
00645         rl->rl_vlc[0][i].run   = run;
00646     }
00647 }
00648 
00649 void ff_mpeg12_common_init(MpegEncContext *s)
00650 {
00651 
00652     s->y_dc_scale_table =
00653     s->c_dc_scale_table = ff_mpeg2_dc_scale_table[s->intra_dc_precision];
00654 
00655 }
00656 
00657 void ff_mpeg1_clean_buffers(MpegEncContext *s)
00658 {
00659     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
00660     s->last_dc[1] = s->last_dc[0];
00661     s->last_dc[2] = s->last_dc[0];
00662     memset(s->last_mv, 0, sizeof(s->last_mv));
00663 }
00664 
00665 
00666 /******************************************/
00667 /* decoding */
00668 
00669 VLC ff_dc_lum_vlc;
00670 VLC ff_dc_chroma_vlc;
00671 
00672 static VLC mbincr_vlc;
00673 static VLC mb_ptype_vlc;
00674 static VLC mb_btype_vlc;
00675 static VLC mb_pat_vlc;
00676 
00677 av_cold void ff_mpeg12_init_vlcs(void)
00678 {
00679     static int done = 0;
00680 
00681     if (!done) {
00682         done = 1;
00683 
00684         INIT_VLC_STATIC(&ff_dc_lum_vlc, DC_VLC_BITS, 12,
00685                         ff_mpeg12_vlc_dc_lum_bits, 1, 1,
00686                         ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
00687         INIT_VLC_STATIC(&ff_dc_chroma_vlc,  DC_VLC_BITS, 12,
00688                         ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
00689                         ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
00690         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
00691                         &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
00692                         &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
00693         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
00694                         &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
00695                         &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
00696         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
00697                         &ff_mpeg12_mbPatTable[0][1], 2, 1,
00698                         &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
00699 
00700         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
00701                         &table_mb_ptype[0][1], 2, 1,
00702                         &table_mb_ptype[0][0], 2, 1, 64);
00703         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
00704                         &table_mb_btype[0][1], 2, 1,
00705                         &table_mb_btype[0][0], 2, 1, 64);
00706         ff_init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
00707         ff_init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
00708 
00709         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
00710         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
00711     }
00712 }
00713 
00714 static inline int get_dmv(MpegEncContext *s)
00715 {
00716     if (get_bits1(&s->gb))
00717         return 1 - (get_bits1(&s->gb) << 1);
00718     else
00719         return 0;
00720 }
00721 
00722 static inline int get_qscale(MpegEncContext *s)
00723 {
00724     int qscale = get_bits(&s->gb, 5);
00725     if (s->q_scale_type) {
00726         return non_linear_qscale[qscale];
00727     } else {
00728         return qscale << 1;
00729     }
00730 }
00731 
00732 static void exchange_uv(MpegEncContext *s)
00733 {
00734     DCTELEM (*tmp)[64];
00735 
00736     tmp           = s->pblocks[4];
00737     s->pblocks[4] = s->pblocks[5];
00738     s->pblocks[5] = tmp;
00739 }
00740 
00741 /* motion type (for MPEG-2) */
00742 #define MT_FIELD 1
00743 #define MT_FRAME 2
00744 #define MT_16X8  2
00745 #define MT_DMV   3
00746 
00747 static int mpeg_decode_mb(MpegEncContext *s, DCTELEM block[12][64])
00748 {
00749     int i, j, k, cbp, val, mb_type, motion_type;
00750     const int mb_block_count = 4 + (1 << s->chroma_format);
00751 
00752     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
00753 
00754     assert(s->mb_skipped == 0);
00755 
00756     if (s->mb_skip_run-- != 0) {
00757         if (s->pict_type == AV_PICTURE_TYPE_P) {
00758             s->mb_skipped = 1;
00759             s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
00760         } else {
00761             int mb_type;
00762 
00763             if (s->mb_x)
00764                 mb_type = s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
00765             else
00766                 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
00767             if (IS_INTRA(mb_type))
00768                 return -1;
00769             s->current_picture.f.mb_type[s->mb_x + s->mb_y*s->mb_stride] =
00770                 mb_type | MB_TYPE_SKIP;
00771 //            assert(s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
00772 
00773             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
00774                 s->mb_skipped = 1;
00775         }
00776 
00777         return 0;
00778     }
00779 
00780     switch (s->pict_type) {
00781     default:
00782     case AV_PICTURE_TYPE_I:
00783         if (get_bits1(&s->gb) == 0) {
00784             if (get_bits1(&s->gb) == 0) {
00785                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
00786                 return -1;
00787             }
00788             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
00789         } else {
00790             mb_type = MB_TYPE_INTRA;
00791         }
00792         break;
00793     case AV_PICTURE_TYPE_P:
00794         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
00795         if (mb_type < 0) {
00796             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
00797             return -1;
00798         }
00799         mb_type = ptype2mb_type[mb_type];
00800         break;
00801     case AV_PICTURE_TYPE_B:
00802         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
00803         if (mb_type < 0) {
00804             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
00805             return -1;
00806         }
00807         mb_type = btype2mb_type[mb_type];
00808         break;
00809     }
00810     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
00811 //    motion_type = 0; /* avoid warning */
00812     if (IS_INTRA(mb_type)) {
00813         s->dsp.clear_blocks(s->block[0]);
00814 
00815         if (!s->chroma_y_shift) {
00816             s->dsp.clear_blocks(s->block[6]);
00817         }
00818 
00819         /* compute DCT type */
00820         if (s->picture_structure == PICT_FRAME && // FIXME add an interlaced_dct coded var?
00821             !s->frame_pred_frame_dct) {
00822             s->interlaced_dct = get_bits1(&s->gb);
00823         }
00824 
00825         if (IS_QUANT(mb_type))
00826             s->qscale = get_qscale(s);
00827 
00828         if (s->concealment_motion_vectors) {
00829             /* just parse them */
00830             if (s->picture_structure != PICT_FRAME)
00831                 skip_bits1(&s->gb); /* field select */
00832 
00833             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
00834                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
00835             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
00836                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
00837 
00838             skip_bits1(&s->gb); /* marker */
00839         } else
00840             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
00841         s->mb_intra = 1;
00842         // if 1, we memcpy blocks in xvmcvideo
00843         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
00844             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
00845             if (s->swap_uv) {
00846                 exchange_uv(s);
00847             }
00848         }
00849 
00850         if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
00851             if (s->flags2 & CODEC_FLAG2_FAST) {
00852                 for (i = 0; i < 6; i++) {
00853                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
00854                 }
00855             } else {
00856                 for (i = 0; i < mb_block_count; i++) {
00857                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
00858                         return -1;
00859                 }
00860             }
00861         } else {
00862             for (i = 0; i < 6; i++) {
00863                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
00864                     return -1;
00865             }
00866         }
00867     } else {
00868         if (mb_type & MB_TYPE_ZERO_MV) {
00869             assert(mb_type & MB_TYPE_CBP);
00870 
00871             s->mv_dir = MV_DIR_FORWARD;
00872             if (s->picture_structure == PICT_FRAME) {
00873                 if (!s->frame_pred_frame_dct)
00874                     s->interlaced_dct = get_bits1(&s->gb);
00875                 s->mv_type = MV_TYPE_16X16;
00876             } else {
00877                 s->mv_type = MV_TYPE_FIELD;
00878                 mb_type |= MB_TYPE_INTERLACED;
00879                 s->field_select[0][0] = s->picture_structure - 1;
00880             }
00881 
00882             if (IS_QUANT(mb_type))
00883                 s->qscale = get_qscale(s);
00884 
00885             s->last_mv[0][0][0] = 0;
00886             s->last_mv[0][0][1] = 0;
00887             s->last_mv[0][1][0] = 0;
00888             s->last_mv[0][1][1] = 0;
00889             s->mv[0][0][0] = 0;
00890             s->mv[0][0][1] = 0;
00891         } else {
00892             assert(mb_type & MB_TYPE_L0L1);
00893             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
00894             /* get additional motion vector type */
00895             if (s->frame_pred_frame_dct)
00896                 motion_type = MT_FRAME;
00897             else {
00898                 motion_type = get_bits(&s->gb, 2);
00899                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
00900                     s->interlaced_dct = get_bits1(&s->gb);
00901             }
00902 
00903             if (IS_QUANT(mb_type))
00904                 s->qscale = get_qscale(s);
00905 
00906             /* motion vectors */
00907             s->mv_dir = (mb_type >> 13) & 3;
00908             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
00909             switch (motion_type) {
00910             case MT_FRAME: /* or MT_16X8 */
00911                 if (s->picture_structure == PICT_FRAME) {
00912                     mb_type |= MB_TYPE_16x16;
00913                     s->mv_type = MV_TYPE_16X16;
00914                     for (i = 0; i < 2; i++) {
00915                         if (USES_LIST(mb_type, i)) {
00916                             /* MT_FRAME */
00917                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
00918                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
00919                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
00920                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
00921                             /* full_pel: only for MPEG-1 */
00922                             if (s->full_pel[i]) {
00923                                 s->mv[i][0][0] <<= 1;
00924                                 s->mv[i][0][1] <<= 1;
00925                             }
00926                         }
00927                     }
00928                 } else {
00929                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
00930                     s->mv_type = MV_TYPE_16X8;
00931                     for (i = 0; i < 2; i++) {
00932                         if (USES_LIST(mb_type, i)) {
00933                             /* MT_16X8 */
00934                             for (j = 0; j < 2; j++) {
00935                                 s->field_select[i][j] = get_bits1(&s->gb);
00936                                 for (k = 0; k < 2; k++) {
00937                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
00938                                                              s->last_mv[i][j][k]);
00939                                     s->last_mv[i][j][k] = val;
00940                                     s->mv[i][j][k]      = val;
00941                                 }
00942                             }
00943                         }
00944                     }
00945                 }
00946                 break;
00947             case MT_FIELD:
00948                 s->mv_type = MV_TYPE_FIELD;
00949                 if (s->picture_structure == PICT_FRAME) {
00950                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
00951                     for (i = 0; i < 2; i++) {
00952                         if (USES_LIST(mb_type, i)) {
00953                             for (j = 0; j < 2; j++) {
00954                                 s->field_select[i][j] = get_bits1(&s->gb);
00955                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
00956                                                          s->last_mv[i][j][0]);
00957                                 s->last_mv[i][j][0] = val;
00958                                 s->mv[i][j][0]      = val;
00959                                 av_dlog(s->avctx, "fmx=%d\n", val);
00960                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
00961                                                          s->last_mv[i][j][1] >> 1);
00962                                 s->last_mv[i][j][1] = val << 1;
00963                                 s->mv[i][j][1]      = val;
00964                                 av_dlog(s->avctx, "fmy=%d\n", val);
00965                             }
00966                         }
00967                     }
00968                 } else {
00969                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
00970                     for (i = 0; i < 2; i++) {
00971                         if (USES_LIST(mb_type, i)) {
00972                             s->field_select[i][0] = get_bits1(&s->gb);
00973                             for (k = 0; k < 2; k++) {
00974                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
00975                                                          s->last_mv[i][0][k]);
00976                                 s->last_mv[i][0][k] = val;
00977                                 s->last_mv[i][1][k] = val;
00978                                 s->mv[i][0][k]      = val;
00979                             }
00980                         }
00981                     }
00982                 }
00983                 break;
00984             case MT_DMV:
00985                 s->mv_type = MV_TYPE_DMV;
00986                 for (i = 0; i < 2; i++) {
00987                     if (USES_LIST(mb_type, i)) {
00988                         int dmx, dmy, mx, my, m;
00989                         const int my_shift = s->picture_structure == PICT_FRAME;
00990 
00991                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
00992                                                 s->last_mv[i][0][0]);
00993                         s->last_mv[i][0][0] = mx;
00994                         s->last_mv[i][1][0] = mx;
00995                         dmx = get_dmv(s);
00996                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
00997                                                  s->last_mv[i][0][1] >> my_shift);
00998                         dmy = get_dmv(s);
00999 
01000 
01001                         s->last_mv[i][0][1] = my << my_shift;
01002                         s->last_mv[i][1][1] = my << my_shift;
01003 
01004                         s->mv[i][0][0] = mx;
01005                         s->mv[i][0][1] = my;
01006                         s->mv[i][1][0] = mx; // not used
01007                         s->mv[i][1][1] = my; // not used
01008 
01009                         if (s->picture_structure == PICT_FRAME) {
01010                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
01011 
01012                             // m = 1 + 2 * s->top_field_first;
01013                             m = s->top_field_first ? 1 : 3;
01014 
01015                             /* top -> top pred */
01016                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
01017                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
01018                             m = 4 - m;
01019                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
01020                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
01021                         } else {
01022                             mb_type |= MB_TYPE_16x16;
01023 
01024                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
01025                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
01026                             if (s->picture_structure == PICT_TOP_FIELD)
01027                                 s->mv[i][2][1]--;
01028                             else
01029                                 s->mv[i][2][1]++;
01030                         }
01031                     }
01032                 }
01033                 break;
01034             default:
01035                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
01036                 return -1;
01037             }
01038         }
01039 
01040         s->mb_intra = 0;
01041         if (HAS_CBP(mb_type)) {
01042             s->dsp.clear_blocks(s->block[0]);
01043 
01044             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
01045             if (mb_block_count > 6) {
01046                  cbp <<= mb_block_count - 6;
01047                  cbp  |= get_bits(&s->gb, mb_block_count - 6);
01048                  s->dsp.clear_blocks(s->block[6]);
01049             }
01050             if (cbp <= 0) {
01051                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
01052                 return -1;
01053             }
01054 
01055             //if 1, we memcpy blocks in xvmcvideo
01056             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
01057                 ff_xvmc_pack_pblocks(s, cbp);
01058                 if (s->swap_uv) {
01059                     exchange_uv(s);
01060                 }
01061             }
01062 
01063             if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
01064                 if (s->flags2 & CODEC_FLAG2_FAST) {
01065                     for (i = 0; i < 6; i++) {
01066                         if (cbp & 32) {
01067                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
01068                         } else {
01069                             s->block_last_index[i] = -1;
01070                         }
01071                         cbp += cbp;
01072                     }
01073                 } else {
01074                     cbp <<= 12-mb_block_count;
01075 
01076                     for (i = 0; i < mb_block_count; i++) {
01077                         if (cbp & (1 << 11)) {
01078                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
01079                                 return -1;
01080                         } else {
01081                             s->block_last_index[i] = -1;
01082                         }
01083                         cbp += cbp;
01084                     }
01085                 }
01086             } else {
01087                 if (s->flags2 & CODEC_FLAG2_FAST) {
01088                     for (i = 0; i < 6; i++) {
01089                         if (cbp & 32) {
01090                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
01091                         } else {
01092                             s->block_last_index[i] = -1;
01093                         }
01094                         cbp += cbp;
01095                     }
01096                 } else {
01097                     for (i = 0; i < 6; i++) {
01098                         if (cbp & 32) {
01099                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
01100                                 return -1;
01101                         } else {
01102                             s->block_last_index[i] = -1;
01103                         }
01104                         cbp += cbp;
01105                     }
01106                 }
01107             }
01108         } else {
01109             for (i = 0; i < 12; i++)
01110                 s->block_last_index[i] = -1;
01111         }
01112     }
01113 
01114     s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
01115 
01116     return 0;
01117 }
01118 
01119 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
01120 {
01121     Mpeg1Context *s = avctx->priv_data;
01122     MpegEncContext *s2 = &s->mpeg_enc_ctx;
01123     int i;
01124 
01125     /* we need some permutation to store matrices,
01126      * until MPV_common_init() sets the real permutation. */
01127     for (i = 0; i < 64; i++)
01128        s2->dsp.idct_permutation[i]=i;
01129 
01130     MPV_decode_defaults(s2);
01131 
01132     s->mpeg_enc_ctx.avctx  = avctx;
01133     s->mpeg_enc_ctx.flags  = avctx->flags;
01134     s->mpeg_enc_ctx.flags2 = avctx->flags2;
01135     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
01136     ff_mpeg12_init_vlcs();
01137 
01138     s->mpeg_enc_ctx_allocated      = 0;
01139     s->mpeg_enc_ctx.picture_number = 0;
01140     s->repeat_field                = 0;
01141     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
01142     avctx->color_range = AVCOL_RANGE_MPEG;
01143     if (avctx->codec->id == CODEC_ID_MPEG1VIDEO)
01144         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
01145     else
01146         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
01147     return 0;
01148 }
01149 
01150 static int mpeg_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
01151 {
01152     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
01153     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
01154     int err;
01155 
01156     if (avctx == avctx_from || !ctx_from->mpeg_enc_ctx_allocated || !s1->context_initialized)
01157         return 0;
01158 
01159     err = ff_mpeg_update_thread_context(avctx, avctx_from);
01160     if (err) return err;
01161 
01162     if (!ctx->mpeg_enc_ctx_allocated)
01163         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
01164 
01165     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
01166         s->picture_number++;
01167 
01168     return 0;
01169 }
01170 
01171 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
01172                                  const uint8_t *new_perm)
01173 {
01174     uint16_t temp_matrix[64];
01175     int i;
01176 
01177     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
01178 
01179     for (i = 0; i < 64; i++) {
01180         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
01181     }
01182 }
01183 
01184 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
01185     PIX_FMT_XVMC_MPEG2_IDCT,
01186     PIX_FMT_XVMC_MPEG2_MC,
01187     PIX_FMT_NONE };
01188 
01189 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
01190 {
01191     Mpeg1Context *s1 = avctx->priv_data;
01192     MpegEncContext *s = &s1->mpeg_enc_ctx;
01193 
01194     if (avctx->xvmc_acceleration)
01195         return avctx->get_format(avctx, pixfmt_xvmc_mpg2_420);
01196     else if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
01197         if (avctx->codec_id == CODEC_ID_MPEG1VIDEO)
01198             return PIX_FMT_VDPAU_MPEG1;
01199         else
01200             return PIX_FMT_VDPAU_MPEG2;
01201     } else {
01202         if (s->chroma_format <  2)
01203             return avctx->get_format(avctx, ff_hwaccel_pixfmt_list_420);
01204         else if (s->chroma_format == 2)
01205             return PIX_FMT_YUV422P;
01206         else
01207             return PIX_FMT_YUV444P;
01208     }
01209 }
01210 
01211 /* Call this function when we know all parameters.
01212  * It may be called in different places for MPEG-1 and MPEG-2. */
01213 static int mpeg_decode_postinit(AVCodecContext *avctx)
01214 {
01215     Mpeg1Context *s1 = avctx->priv_data;
01216     MpegEncContext *s = &s1->mpeg_enc_ctx;
01217     uint8_t old_permutation[64];
01218 
01219     if ((s1->mpeg_enc_ctx_allocated == 0) ||
01220         avctx->coded_width  != s->width   ||
01221         avctx->coded_height != s->height  ||
01222         s1->save_width           != s->width                ||
01223         s1->save_height          != s->height               ||
01224         s1->save_aspect_info     != s->aspect_ratio_info    ||
01225         s1->save_progressive_seq != s->progressive_sequence ||
01226         0)
01227     {
01228 
01229         if (s1->mpeg_enc_ctx_allocated) {
01230             ParseContext pc = s->parse_context;
01231             s->parse_context.buffer = 0;
01232             MPV_common_end(s);
01233             s->parse_context = pc;
01234         }
01235 
01236         if ((s->width == 0) || (s->height == 0))
01237             return -2;
01238 
01239         avcodec_set_dimensions(avctx, s->width, s->height);
01240         avctx->bit_rate          = s->bit_rate;
01241         s1->save_aspect_info     = s->aspect_ratio_info;
01242         s1->save_width           = s->width;
01243         s1->save_height          = s->height;
01244         s1->save_progressive_seq = s->progressive_sequence;
01245 
01246         /* low_delay may be forced, in this case we will have B-frames
01247          * that behave like P-frames. */
01248         avctx->has_b_frames = !s->low_delay;
01249 
01250         assert((avctx->sub_id == 1) == (avctx->codec_id == CODEC_ID_MPEG1VIDEO));
01251         if (avctx->codec_id == CODEC_ID_MPEG1VIDEO) {
01252             //MPEG-1 fps
01253             avctx->time_base.den = avpriv_frame_rate_tab[s->frame_rate_index].num;
01254             avctx->time_base.num = avpriv_frame_rate_tab[s->frame_rate_index].den;
01255             //MPEG-1 aspect
01256             avctx->sample_aspect_ratio = av_d2q(1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
01257             avctx->ticks_per_frame=1;
01258         } else {//MPEG-2
01259         //MPEG-2 fps
01260             av_reduce(&s->avctx->time_base.den,
01261                       &s->avctx->time_base.num,
01262                       avpriv_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
01263                       avpriv_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
01264                       1 << 30);
01265             avctx->ticks_per_frame = 2;
01266             //MPEG-2 aspect
01267             if (s->aspect_ratio_info > 1) {
01268                 AVRational dar =
01269                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
01270                                       (AVRational) {s1->pan_scan.width, s1->pan_scan.height}),
01271                              (AVRational) {s->width, s->height});
01272 
01273                 // we ignore the spec here and guess a bit as reality does not match the spec, see for example
01274                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
01275                 // issue1613, 621, 562
01276                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
01277                    (av_cmp_q(dar, (AVRational) {4, 3}) && av_cmp_q(dar, (AVRational) {16, 9}))) {
01278                     s->avctx->sample_aspect_ratio =
01279                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
01280                                  (AVRational) {s->width, s->height});
01281                 } else {
01282                     s->avctx->sample_aspect_ratio =
01283                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
01284                                  (AVRational) {s1->pan_scan.width, s1->pan_scan.height});
01285 //issue1613 4/3 16/9 -> 16/9
01286 //res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
01287 //widescreen-issue562.mpg 4/3 16/9 -> 16/9
01288 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
01289 //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);
01290 //av_log(NULL, AV_LOG_ERROR, "B %d/%d\n", s->avctx->sample_aspect_ratio.num, s->avctx->sample_aspect_ratio.den);
01291                 }
01292             } else {
01293                 s->avctx->sample_aspect_ratio =
01294                     ff_mpeg2_aspect[s->aspect_ratio_info];
01295             }
01296         } // MPEG-2
01297 
01298         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
01299         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
01300         // until then pix_fmt may be changed right after codec init
01301         if (avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
01302             avctx->hwaccel                            ||
01303             s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
01304             if (avctx->idct_algo == FF_IDCT_AUTO)
01305                 avctx->idct_algo = FF_IDCT_SIMPLE;
01306 
01307         /* Quantization matrices may need reordering
01308          * if DCT permutation is changed. */
01309         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
01310 
01311         if (MPV_common_init(s) < 0)
01312             return -2;
01313 
01314         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
01315         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->dsp.idct_permutation);
01316         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->dsp.idct_permutation);
01317         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->dsp.idct_permutation);
01318 
01319         s1->mpeg_enc_ctx_allocated = 1;
01320     }
01321     return 0;
01322 }
01323 
01324 static int mpeg1_decode_picture(AVCodecContext *avctx,
01325                                 const uint8_t *buf, int buf_size)
01326 {
01327     Mpeg1Context *s1 = avctx->priv_data;
01328     MpegEncContext *s = &s1->mpeg_enc_ctx;
01329     int ref, f_code, vbv_delay;
01330 
01331     init_get_bits(&s->gb, buf, buf_size*8);
01332 
01333     ref = get_bits(&s->gb, 10); /* temporal ref */
01334     s->pict_type = get_bits(&s->gb, 3);
01335     if (s->pict_type == 0 || s->pict_type > 3)
01336         return -1;
01337 
01338     vbv_delay = get_bits(&s->gb, 16);
01339     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) {
01340         s->full_pel[0] = get_bits1(&s->gb);
01341         f_code = get_bits(&s->gb, 3);
01342         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
01343             return -1;
01344         s->mpeg_f_code[0][0] = f_code;
01345         s->mpeg_f_code[0][1] = f_code;
01346     }
01347     if (s->pict_type == AV_PICTURE_TYPE_B) {
01348         s->full_pel[1] = get_bits1(&s->gb);
01349         f_code = get_bits(&s->gb, 3);
01350         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
01351             return -1;
01352         s->mpeg_f_code[1][0] = f_code;
01353         s->mpeg_f_code[1][1] = f_code;
01354     }
01355     s->current_picture.f.pict_type = s->pict_type;
01356     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
01357 
01358     if (avctx->debug & FF_DEBUG_PICT_INFO)
01359         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
01360 
01361     s->y_dc_scale = 8;
01362     s->c_dc_scale = 8;
01363     return 0;
01364 }
01365 
01366 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
01367 {
01368     MpegEncContext *s= &s1->mpeg_enc_ctx;
01369     int horiz_size_ext, vert_size_ext;
01370     int bit_rate_ext;
01371 
01372     skip_bits(&s->gb, 1); /* profile and level esc*/
01373     s->avctx->profile       = get_bits(&s->gb, 3);
01374     s->avctx->level         = get_bits(&s->gb, 4);
01375     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
01376     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
01377     horiz_size_ext          = get_bits(&s->gb, 2);
01378     vert_size_ext           = get_bits(&s->gb, 2);
01379     s->width  |= (horiz_size_ext << 12);
01380     s->height |= (vert_size_ext  << 12);
01381     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
01382     s->bit_rate += (bit_rate_ext << 18) * 400;
01383     skip_bits1(&s->gb); /* marker */
01384     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
01385 
01386     s->low_delay = get_bits1(&s->gb);
01387     if (s->flags & CODEC_FLAG_LOW_DELAY)
01388         s->low_delay = 1;
01389 
01390     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
01391     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
01392 
01393     av_dlog(s->avctx, "sequence extension\n");
01394     s->codec_id      = s->avctx->codec_id = CODEC_ID_MPEG2VIDEO;
01395     s->avctx->sub_id = 2; /* indicates MPEG-2 found */
01396 
01397     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01398         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
01399                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
01400 
01401 }
01402 
01403 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
01404 {
01405     MpegEncContext *s = &s1->mpeg_enc_ctx;
01406     int color_description, w, h;
01407 
01408     skip_bits(&s->gb, 3); /* video format */
01409     color_description = get_bits1(&s->gb);
01410     if (color_description) {
01411         s->avctx->color_primaries = get_bits(&s->gb, 8);
01412         s->avctx->color_trc       = get_bits(&s->gb, 8);
01413         s->avctx->colorspace      = get_bits(&s->gb, 8);
01414     }
01415     w = get_bits(&s->gb, 14);
01416     skip_bits(&s->gb, 1); //marker
01417     h = get_bits(&s->gb, 14);
01418     // remaining 3 bits are zero padding
01419 
01420     s1->pan_scan.width  = 16 * w;
01421     s1->pan_scan.height = 16 * h;
01422 
01423     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01424         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
01425 }
01426 
01427 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
01428 {
01429     MpegEncContext *s = &s1->mpeg_enc_ctx;
01430     int i, nofco;
01431 
01432     nofco = 1;
01433     if (s->progressive_sequence) {
01434         if (s->repeat_first_field) {
01435             nofco++;
01436             if (s->top_field_first)
01437                 nofco++;
01438         }
01439     } else {
01440         if (s->picture_structure == PICT_FRAME) {
01441             nofco++;
01442             if (s->repeat_first_field)
01443                 nofco++;
01444         }
01445     }
01446     for (i = 0; i < nofco; i++) {
01447         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
01448         skip_bits(&s->gb, 1); // marker
01449         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
01450         skip_bits(&s->gb, 1); // marker
01451     }
01452 
01453     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
01454         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
01455                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
01456                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
01457                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
01458 }
01459 
01460 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra)
01461 {
01462     int i;
01463 
01464     for (i = 0; i < 64; i++) {
01465         int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
01466         int v = get_bits(&s->gb, 8);
01467         if (v == 0) {
01468             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
01469             return -1;
01470         }
01471         if (intra && i == 0 && v != 8) {
01472             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
01473             v = 8; // needed by pink.mpg / issue1046
01474         }
01475         matrix0[j] = v;
01476         if (matrix1)
01477             matrix1[j] = v;
01478     }
01479     return 0;
01480 }
01481 
01482 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
01483 {
01484     av_dlog(s->avctx, "matrix extension\n");
01485 
01486     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
01487     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
01488     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
01489     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
01490 }
01491 
01492 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
01493 {
01494     MpegEncContext *s = &s1->mpeg_enc_ctx;
01495 
01496     s->full_pel[0] = s->full_pel[1] = 0;
01497     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
01498     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
01499     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
01500     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
01501     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
01502         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
01503         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
01504             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
01505                 s->pict_type = AV_PICTURE_TYPE_I;
01506             else
01507                 s->pict_type = AV_PICTURE_TYPE_P;
01508         } else
01509             s->pict_type = AV_PICTURE_TYPE_B;
01510         s->current_picture.f.pict_type = s->pict_type;
01511         s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
01512     }
01513     s->intra_dc_precision         = get_bits(&s->gb, 2);
01514     s->picture_structure          = get_bits(&s->gb, 2);
01515     s->top_field_first            = get_bits1(&s->gb);
01516     s->frame_pred_frame_dct       = get_bits1(&s->gb);
01517     s->concealment_motion_vectors = get_bits1(&s->gb);
01518     s->q_scale_type               = get_bits1(&s->gb);
01519     s->intra_vlc_format           = get_bits1(&s->gb);
01520     s->alternate_scan             = get_bits1(&s->gb);
01521     s->repeat_first_field         = get_bits1(&s->gb);
01522     s->chroma_420_type            = get_bits1(&s->gb);
01523     s->progressive_frame          = get_bits1(&s->gb);
01524 
01525     if (s->progressive_sequence && !s->progressive_frame) {
01526         s->progressive_frame = 1;
01527         av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
01528     }
01529 
01530     if (s->picture_structure == 0 || (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
01531         av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
01532         s->picture_structure = PICT_FRAME;
01533     }
01534 
01535     if (s->progressive_sequence && !s->frame_pred_frame_dct) {
01536         av_log(s->avctx, AV_LOG_ERROR, "invalid frame_pred_frame_dct\n");
01537         s->frame_pred_frame_dct = 1;
01538     }
01539 
01540     if (s->picture_structure == PICT_FRAME) {
01541         s->first_field = 0;
01542         s->v_edge_pos  = 16 * s->mb_height;
01543     } else {
01544         s->first_field ^= 1;
01545         s->v_edge_pos   = 8 * s->mb_height;
01546         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
01547     }
01548 
01549     if (s->alternate_scan) {
01550         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
01551         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
01552     } else {
01553         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
01554         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
01555     }
01556 
01557     /* composite display not parsed */
01558     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
01559     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
01560     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
01561     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
01562     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
01563     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
01564     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
01565     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
01566     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
01567 }
01568 
01569 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
01570 {
01571     AVCodecContext *avctx = s->avctx;
01572     Mpeg1Context *s1 = (Mpeg1Context*)s;
01573 
01574     /* start frame decoding */
01575     if (s->first_field || s->picture_structure == PICT_FRAME) {
01576         if (MPV_frame_start(s, avctx) < 0)
01577             return -1;
01578 
01579         ff_er_frame_start(s);
01580 
01581         /* first check if we must repeat the frame */
01582         s->current_picture_ptr->f.repeat_pict = 0;
01583         if (s->repeat_first_field) {
01584             if (s->progressive_sequence) {
01585                 if (s->top_field_first)
01586                     s->current_picture_ptr->f.repeat_pict = 4;
01587                 else
01588                     s->current_picture_ptr->f.repeat_pict = 2;
01589             } else if (s->progressive_frame) {
01590                 s->current_picture_ptr->f.repeat_pict = 1;
01591             }
01592         }
01593 
01594         *s->current_picture_ptr->f.pan_scan = s1->pan_scan;
01595 
01596         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
01597             ff_thread_finish_setup(avctx);
01598     } else { // second field
01599         int i;
01600 
01601         if (!s->current_picture_ptr) {
01602             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
01603             return -1;
01604         }
01605 
01606         for (i = 0; i < 4; i++) {
01607             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
01608             if (s->picture_structure == PICT_BOTTOM_FIELD) {
01609                 s->current_picture.f.data[i] += s->current_picture_ptr->f.linesize[i];
01610             }
01611         }
01612     }
01613 
01614     if (avctx->hwaccel) {
01615         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
01616             return -1;
01617     }
01618 
01619 // MPV_frame_start will call this function too,
01620 // but we need to call it on every field
01621     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
01622         if (ff_xvmc_field_start(s, avctx) < 0)
01623             return -1;
01624 
01625     return 0;
01626 }
01627 
01628 #define DECODE_SLICE_ERROR -1
01629 #define DECODE_SLICE_OK     0
01630 
01637 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
01638                              const uint8_t **buf, int buf_size)
01639 {
01640     AVCodecContext *avctx = s->avctx;
01641     const int lowres      = s->avctx->lowres;
01642     const int field_pic   = s->picture_structure != PICT_FRAME;
01643 
01644     s->resync_mb_x =
01645     s->resync_mb_y = -1;
01646 
01647     assert(mb_y < s->mb_height);
01648 
01649     init_get_bits(&s->gb, *buf, buf_size * 8);
01650 
01651     ff_mpeg1_clean_buffers(s);
01652     s->interlaced_dct = 0;
01653 
01654     s->qscale = get_qscale(s);
01655 
01656     if (s->qscale == 0) {
01657         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
01658         return -1;
01659     }
01660 
01661     /* extra slice info */
01662     while (get_bits1(&s->gb) != 0) {
01663         skip_bits(&s->gb, 8);
01664     }
01665 
01666     s->mb_x = 0;
01667 
01668     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
01669         skip_bits1(&s->gb);
01670     } else {
01671         while (get_bits_left(&s->gb) > 0) {
01672             int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
01673             if (code < 0) {
01674                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
01675                 return -1;
01676             }
01677             if (code >= 33) {
01678                 if (code == 33) {
01679                     s->mb_x += 33;
01680                 }
01681                 /* otherwise, stuffing, nothing to do */
01682             } else {
01683                 s->mb_x += code;
01684                 break;
01685             }
01686         }
01687     }
01688 
01689     if (s->mb_x >= (unsigned)s->mb_width) {
01690         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
01691         return -1;
01692     }
01693 
01694     if (avctx->hwaccel) {
01695         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
01696         int start_code = -1;
01697         buf_end = avpriv_mpv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
01698         if (buf_end < *buf + buf_size)
01699             buf_end -= 4;
01700         s->mb_y = mb_y;
01701         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
01702             return DECODE_SLICE_ERROR;
01703         *buf = buf_end;
01704         return DECODE_SLICE_OK;
01705     }
01706 
01707     s->resync_mb_x = s->mb_x;
01708     s->resync_mb_y = s->mb_y = mb_y;
01709     s->mb_skip_run = 0;
01710     ff_init_block_index(s);
01711 
01712     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
01713         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
01714              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",
01715                     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],
01716                     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")),
01717                     s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
01718                     s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
01719                     s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
01720         }
01721     }
01722 
01723     for (;;) {
01724         // If 1, we memcpy blocks in xvmcvideo.
01725         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
01726             ff_xvmc_init_block(s); // set s->block
01727 
01728         if (mpeg_decode_mb(s, s->block) < 0)
01729             return -1;
01730 
01731         if (s->current_picture.f.motion_val[0] && !s->encoding) { // note motion_val is normally NULL unless we want to extract the MVs
01732             const int wrap = s->b8_stride;
01733             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
01734             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
01735             int motion_x, motion_y, dir, i;
01736 
01737             for (i = 0; i < 2; i++) {
01738                 for (dir = 0; dir < 2; dir++) {
01739                     if (s->mb_intra || (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
01740                         motion_x = motion_y = 0;
01741                     } else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)) {
01742                         motion_x = s->mv[dir][0][0];
01743                         motion_y = s->mv[dir][0][1];
01744                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
01745                         motion_x = s->mv[dir][i][0];
01746                         motion_y = s->mv[dir][i][1];
01747                     }
01748 
01749                     s->current_picture.f.motion_val[dir][xy    ][0] = motion_x;
01750                     s->current_picture.f.motion_val[dir][xy    ][1] = motion_y;
01751                     s->current_picture.f.motion_val[dir][xy + 1][0] = motion_x;
01752                     s->current_picture.f.motion_val[dir][xy + 1][1] = motion_y;
01753                     s->current_picture.f.ref_index [dir][b8_xy    ] =
01754                     s->current_picture.f.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
01755                     assert(s->field_select[dir][i] == 0 || s->field_select[dir][i] == 1);
01756                 }
01757                 xy += wrap;
01758                 b8_xy +=2;
01759             }
01760         }
01761 
01762         s->dest[0] += 16 >> lowres;
01763         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
01764         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
01765 
01766         MPV_decode_mb(s, s->block);
01767 
01768         if (++s->mb_x >= s->mb_width) {
01769             const int mb_size = 16 >> s->avctx->lowres;
01770 
01771             ff_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
01772             MPV_report_decode_progress(s);
01773 
01774             s->mb_x = 0;
01775             s->mb_y += 1 << field_pic;
01776 
01777             if (s->mb_y >= s->mb_height) {
01778                 int left   = get_bits_left(&s->gb);
01779                 int is_d10 = s->chroma_format == 2 && s->pict_type == AV_PICTURE_TYPE_I && avctx->profile == 0 && avctx->level == 5
01780                              && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
01781                              && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
01782 
01783                 if (left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
01784                     || ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
01785                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
01786                     return -1;
01787                 } else
01788                     goto eos;
01789             }
01790 
01791             ff_init_block_index(s);
01792         }
01793 
01794         /* skip mb handling */
01795         if (s->mb_skip_run == -1) {
01796             /* read increment again */
01797             s->mb_skip_run = 0;
01798             for (;;) {
01799                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
01800                 if (code < 0) {
01801                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
01802                     return -1;
01803                 }
01804                 if (code >= 33) {
01805                     if (code == 33) {
01806                         s->mb_skip_run += 33;
01807                     } else if (code == 35) {
01808                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
01809                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
01810                             return -1;
01811                         }
01812                         goto eos; /* end of slice */
01813                     }
01814                     /* otherwise, stuffing, nothing to do */
01815                 } else {
01816                     s->mb_skip_run += code;
01817                     break;
01818                 }
01819             }
01820             if (s->mb_skip_run) {
01821                 int i;
01822                 if (s->pict_type == AV_PICTURE_TYPE_I) {
01823                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
01824                     return -1;
01825                 }
01826 
01827                 /* skip mb */
01828                 s->mb_intra = 0;
01829                 for (i = 0; i < 12; i++)
01830                     s->block_last_index[i] = -1;
01831                 if (s->picture_structure == PICT_FRAME)
01832                     s->mv_type = MV_TYPE_16X16;
01833                 else
01834                     s->mv_type = MV_TYPE_FIELD;
01835                 if (s->pict_type == AV_PICTURE_TYPE_P) {
01836                     /* if P type, zero motion vector is implied */
01837                     s->mv_dir             = MV_DIR_FORWARD;
01838                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
01839                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
01840                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
01841                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
01842                 } else {
01843                     /* if B type, reuse previous vectors and directions */
01844                     s->mv[0][0][0] = s->last_mv[0][0][0];
01845                     s->mv[0][0][1] = s->last_mv[0][0][1];
01846                     s->mv[1][0][0] = s->last_mv[1][0][0];
01847                     s->mv[1][0][1] = s->last_mv[1][0][1];
01848                 }
01849             }
01850         }
01851     }
01852 eos: // end of slice
01853     *buf += (get_bits_count(&s->gb)-1)/8;
01854 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
01855     return 0;
01856 }
01857 
01858 static int slice_decode_thread(AVCodecContext *c, void *arg)
01859 {
01860     MpegEncContext *s   = *(void**)arg;
01861     const uint8_t *buf  = s->gb.buffer;
01862     int mb_y            = s->start_mb_y;
01863     const int field_pic = s->picture_structure != PICT_FRAME;
01864 
01865     s->error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
01866 
01867     for (;;) {
01868         uint32_t start_code;
01869         int ret;
01870 
01871         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
01872         emms_c();
01873 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
01874 //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);
01875         if (ret < 0) {
01876             if (c->err_recognition & AV_EF_EXPLODE)
01877                 return ret;
01878             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
01879                 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);
01880         } else {
01881             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);
01882         }
01883 
01884         if (s->mb_y == s->end_mb_y)
01885             return 0;
01886 
01887         start_code = -1;
01888         buf = avpriv_mpv_find_start_code(buf, s->gb.buffer_end, &start_code);
01889         mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
01890         if (s->picture_structure == PICT_BOTTOM_FIELD)
01891             mb_y++;
01892         if (mb_y < 0 || mb_y >= s->end_mb_y)
01893             return -1;
01894     }
01895 }
01896 
01901 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
01902 {
01903     Mpeg1Context *s1 = avctx->priv_data;
01904     MpegEncContext *s = &s1->mpeg_enc_ctx;
01905 
01906     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
01907         return 0;
01908 
01909     if (s->avctx->hwaccel) {
01910         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
01911             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
01912     }
01913 
01914     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
01915         ff_xvmc_field_end(s);
01916 
01917     /* end of slice reached */
01918     if (/*s->mb_y << field_pic == s->mb_height &&*/ !s->first_field) {
01919         /* end of image */
01920 
01921         s->current_picture_ptr->f.qscale_type = FF_QSCALE_TYPE_MPEG2;
01922 
01923         ff_er_frame_end(s);
01924 
01925         MPV_frame_end(s);
01926 
01927         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
01928             *pict = *(AVFrame*)s->current_picture_ptr;
01929             ff_print_debug_info(s, pict);
01930         } else {
01931             if (avctx->active_thread_type & FF_THREAD_FRAME)
01932                 s->picture_number++;
01933             /* latency of 1 frame for I- and P-frames */
01934             /* XXX: use another variable than picture_number */
01935             if (s->last_picture_ptr != NULL) {
01936                 *pict = *(AVFrame*)s->last_picture_ptr;
01937                  ff_print_debug_info(s, pict);
01938             }
01939         }
01940 
01941         return 1;
01942     } else {
01943         return 0;
01944     }
01945 }
01946 
01947 static int mpeg1_decode_sequence(AVCodecContext *avctx,
01948                                  const uint8_t *buf, int buf_size)
01949 {
01950     Mpeg1Context *s1 = avctx->priv_data;
01951     MpegEncContext *s = &s1->mpeg_enc_ctx;
01952     int width, height;
01953     int i, v, j;
01954 
01955     init_get_bits(&s->gb, buf, buf_size*8);
01956 
01957     width  = get_bits(&s->gb, 12);
01958     height = get_bits(&s->gb, 12);
01959     if (width <= 0 || height <= 0)
01960         return -1;
01961     s->aspect_ratio_info = get_bits(&s->gb, 4);
01962     if (s->aspect_ratio_info == 0) {
01963         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
01964         if (avctx->err_recognition & AV_EF_BITSTREAM)
01965             return -1;
01966     }
01967     s->frame_rate_index = get_bits(&s->gb, 4);
01968     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
01969         return -1;
01970     s->bit_rate = get_bits(&s->gb, 18) * 400;
01971     if (get_bits1(&s->gb) == 0) /* marker */
01972         return -1;
01973     s->width  = width;
01974     s->height = height;
01975 
01976     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
01977     skip_bits(&s->gb, 1);
01978 
01979     /* get matrix */
01980     if (get_bits1(&s->gb)) {
01981         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
01982     } else {
01983         for (i = 0; i < 64; i++) {
01984             j = s->dsp.idct_permutation[i];
01985             v = ff_mpeg1_default_intra_matrix[i];
01986             s->intra_matrix[j]        = v;
01987             s->chroma_intra_matrix[j] = v;
01988         }
01989     }
01990     if (get_bits1(&s->gb)) {
01991         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
01992     } else {
01993         for (i = 0; i < 64; i++) {
01994             int j = s->dsp.idct_permutation[i];
01995             v = ff_mpeg1_default_non_intra_matrix[i];
01996             s->inter_matrix[j]        = v;
01997             s->chroma_inter_matrix[j] = v;
01998         }
01999     }
02000 
02001     if (show_bits(&s->gb, 23) != 0) {
02002         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
02003         return -1;
02004     }
02005 
02006     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
02007     s->progressive_sequence = 1;
02008     s->progressive_frame    = 1;
02009     s->picture_structure    = PICT_FRAME;
02010     s->frame_pred_frame_dct = 1;
02011     s->chroma_format        = 1;
02012     s->codec_id             = s->avctx->codec_id = CODEC_ID_MPEG1VIDEO;
02013     avctx->sub_id           = 1; /* indicates MPEG-1 */
02014     s->out_format           = FMT_MPEG1;
02015     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
02016     if (s->flags & CODEC_FLAG_LOW_DELAY)
02017         s->low_delay = 1;
02018 
02019     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
02020         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
02021                s->avctx->rc_buffer_size, s->bit_rate);
02022 
02023     return 0;
02024 }
02025 
02026 static int vcr2_init_sequence(AVCodecContext *avctx)
02027 {
02028     Mpeg1Context *s1 = avctx->priv_data;
02029     MpegEncContext *s = &s1->mpeg_enc_ctx;
02030     int i, v;
02031 
02032     /* start new MPEG-1 context decoding */
02033     s->out_format = FMT_MPEG1;
02034     if (s1->mpeg_enc_ctx_allocated) {
02035         MPV_common_end(s);
02036     }
02037     s->width  = avctx->coded_width;
02038     s->height = avctx->coded_height;
02039     avctx->has_b_frames = 0; // true?
02040     s->low_delay = 1;
02041 
02042     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
02043     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
02044 
02045     if (avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
02046         s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
02047         if (avctx->idct_algo == FF_IDCT_AUTO)
02048             avctx->idct_algo = FF_IDCT_SIMPLE;
02049 
02050     if (MPV_common_init(s) < 0)
02051         return -1;
02052     exchange_uv(s); // common init reset pblocks, so we swap them here
02053     s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
02054     s1->mpeg_enc_ctx_allocated = 1;
02055 
02056     for (i = 0; i < 64; i++) {
02057         int j = s->dsp.idct_permutation[i];
02058         v = ff_mpeg1_default_intra_matrix[i];
02059         s->intra_matrix[j]        = v;
02060         s->chroma_intra_matrix[j] = v;
02061 
02062         v = ff_mpeg1_default_non_intra_matrix[i];
02063         s->inter_matrix[j]        = v;
02064         s->chroma_inter_matrix[j] = v;
02065     }
02066 
02067     s->progressive_sequence  = 1;
02068     s->progressive_frame     = 1;
02069     s->picture_structure     = PICT_FRAME;
02070     s->frame_pred_frame_dct  = 1;
02071     s->chroma_format         = 1;
02072     s->codec_id              = s->avctx->codec_id = CODEC_ID_MPEG2VIDEO;
02073     avctx->sub_id            = 2; /* indicates MPEG-2 */
02074     s1->save_width           = s->width;
02075     s1->save_height          = s->height;
02076     s1->save_progressive_seq = s->progressive_sequence;
02077     return 0;
02078 }
02079 
02080 
02081 static void mpeg_decode_user_data(AVCodecContext *avctx,
02082                                   const uint8_t *p, int buf_size)
02083 {
02084     const uint8_t *buf_end = p + buf_size;
02085 
02086     /* we parse the DTG active format information */
02087     if (buf_end - p >= 5 &&
02088         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
02089         int flags = p[4];
02090         p += 5;
02091         if (flags & 0x80) {
02092             /* skip event id */
02093             p += 2;
02094         }
02095         if (flags & 0x40) {
02096             if (buf_end - p < 1)
02097                 return;
02098             avctx->dtg_active_format = p[0] & 0x0f;
02099         }
02100     }
02101 }
02102 
02103 static void mpeg_decode_gop(AVCodecContext *avctx,
02104                             const uint8_t *buf, int buf_size)
02105 {
02106     Mpeg1Context *s1  = avctx->priv_data;
02107     MpegEncContext *s = &s1->mpeg_enc_ctx;
02108 
02109     int time_code_hours, time_code_minutes;
02110     int time_code_seconds, time_code_pictures;
02111     int broken_link;
02112 
02113     init_get_bits(&s->gb, buf, buf_size*8);
02114 
02115     skip_bits1(&s->gb); /* drop_frame_flag */
02116 
02117     time_code_hours   = get_bits(&s->gb, 5);
02118     time_code_minutes = get_bits(&s->gb, 6);
02119     skip_bits1(&s->gb); // marker bit
02120     time_code_seconds  = get_bits(&s->gb, 6);
02121     time_code_pictures = get_bits(&s->gb, 6);
02122 
02123     s1->closed_gop = get_bits1(&s->gb);
02124     /*broken_link indicate that after editing the
02125       reference frames of the first B-Frames after GOP I-Frame
02126       are missing (open gop)*/
02127     broken_link = get_bits1(&s->gb);
02128 
02129     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
02130         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
02131                time_code_hours, time_code_minutes, time_code_seconds,
02132                time_code_pictures, s1->closed_gop, broken_link);
02133 }
02138 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
02139 {
02140     int i;
02141     uint32_t state = pc->state;
02142 
02143     /* EOF considered as end of frame */
02144     if (buf_size == 0)
02145         return 0;
02146 
02147 /*
02148  0  frame start         -> 1/4
02149  1  first_SEQEXT        -> 0/2
02150  2  first field start   -> 3/0
02151  3  second_SEQEXT       -> 2/0
02152  4  searching end
02153 */
02154 
02155     for (i = 0; i < buf_size; i++) {
02156         assert(pc->frame_start_found >= 0 && pc->frame_start_found <= 4);
02157         if (pc->frame_start_found & 1) {
02158             if (state == EXT_START_CODE && (buf[i] & 0xF0) != 0x80)
02159                 pc->frame_start_found--;
02160             else if (state == EXT_START_CODE + 2) {
02161                 if ((buf[i] & 3) == 3)
02162                     pc->frame_start_found = 0;
02163                 else
02164                     pc->frame_start_found = (pc->frame_start_found + 1) & 3;
02165             }
02166             state++;
02167         } else {
02168             i = avpriv_mpv_find_start_code(buf + i, buf + buf_size, &state) - buf - 1;
02169             if (pc->frame_start_found == 0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE) {
02170                 i++;
02171                 pc->frame_start_found = 4;
02172             }
02173             if (state == SEQ_END_CODE) {
02174                 pc->state=-1;
02175                 return i+1;
02176             }
02177             if (pc->frame_start_found == 2 && state == SEQ_START_CODE)
02178                 pc->frame_start_found = 0;
02179             if (pc->frame_start_found  < 4 && state == EXT_START_CODE)
02180                 pc->frame_start_found++;
02181             if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) {
02182                 if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) {
02183                     pc->frame_start_found = 0;
02184                     pc->state             = -1;
02185                     return i - 3;
02186                 }
02187             }
02188             if (pc->frame_start_found == 0 && s && state == PICTURE_START_CODE) {
02189                 ff_fetch_timestamp(s, i - 3, 1);
02190             }
02191         }
02192     }
02193     pc->state = state;
02194     return END_NOT_FOUND;
02195 }
02196 
02197 static int decode_chunks(AVCodecContext *avctx,
02198                          AVFrame *picture, int *data_size,
02199                          const uint8_t *buf, int buf_size);
02200 
02201 /* handle buffering and image synchronisation */
02202 static int mpeg_decode_frame(AVCodecContext *avctx,
02203                              void *data, int *data_size,
02204                              AVPacket *avpkt)
02205 {
02206     const uint8_t *buf = avpkt->data;
02207     int buf_size = avpkt->size;
02208     Mpeg1Context *s = avctx->priv_data;
02209     AVFrame *picture = data;
02210     MpegEncContext *s2 = &s->mpeg_enc_ctx;
02211     av_dlog(avctx, "fill_buffer\n");
02212 
02213     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
02214         /* special case for last picture */
02215         if (s2->low_delay == 0 && s2->next_picture_ptr) {
02216             *picture = *(AVFrame*)s2->next_picture_ptr;
02217             s2->next_picture_ptr = NULL;
02218 
02219             *data_size = sizeof(AVFrame);
02220         }
02221         return buf_size;
02222     }
02223 
02224     if (s2->flags & CODEC_FLAG_TRUNCATED) {
02225         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
02226 
02227         if (ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0)
02228             return buf_size;
02229     }
02230 
02231     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
02232         vcr2_init_sequence(avctx);
02233 
02234     s->slice_count = 0;
02235 
02236     if (avctx->extradata && !s->extradata_decoded) {
02237         int ret = decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
02238         s->extradata_decoded = 1;
02239         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
02240             return ret;
02241     }
02242 
02243     return decode_chunks(avctx, picture, data_size, buf, buf_size);
02244 }
02245 
02246 static int decode_chunks(AVCodecContext *avctx,
02247                          AVFrame *picture, int *data_size,
02248                          const uint8_t *buf, int buf_size)
02249 {
02250     Mpeg1Context *s = avctx->priv_data;
02251     MpegEncContext *s2 = &s->mpeg_enc_ctx;
02252     const uint8_t *buf_ptr = buf;
02253     const uint8_t *buf_end = buf + buf_size;
02254     int ret, input_size;
02255     int last_code = 0;
02256 
02257     for (;;) {
02258         /* find next start code */
02259         uint32_t start_code = -1;
02260         buf_ptr = avpriv_mpv_find_start_code(buf_ptr, buf_end, &start_code);
02261         if (start_code > 0x1ff) {
02262             if (s2->pict_type != AV_PICTURE_TYPE_B || avctx->skip_frame <= AVDISCARD_DEFAULT) {
02263                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
02264                     int i;
02265 
02266                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
02267                     for (i = 0; i < s->slice_count; i++)
02268                         s2->error_count += s2->thread_context[i]->error_count;
02269                 }
02270 
02271                 if (CONFIG_MPEG_VDPAU_DECODER && avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
02272                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
02273 
02274                 if (slice_end(avctx, picture)) {
02275                     if (s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
02276                         *data_size = sizeof(AVPicture);
02277                 }
02278             }
02279             s2->pict_type = 0;
02280             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
02281         }
02282 
02283         input_size = buf_end - buf_ptr;
02284 
02285         if (avctx->debug & FF_DEBUG_STARTCODE) {
02286             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
02287         }
02288 
02289         /* prepare data for next start code */
02290         switch (start_code) {
02291         case SEQ_START_CODE:
02292             if (last_code == 0) {
02293                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
02294                 s->sync=1;
02295             } else {
02296                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
02297                 if (avctx->err_recognition & AV_EF_EXPLODE)
02298                     return AVERROR_INVALIDDATA;
02299             }
02300             break;
02301 
02302         case PICTURE_START_CODE:
02303             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && s->slice_count) {
02304                 int i;
02305 
02306                 avctx->execute(avctx, slice_decode_thread,
02307                                s2->thread_context, NULL,
02308                                s->slice_count, sizeof(void*));
02309                 for (i = 0; i < s->slice_count; i++)
02310                     s2->error_count += s2->thread_context[i]->error_count;
02311                 s->slice_count = 0;
02312             }
02313             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
02314                 ret = mpeg_decode_postinit(avctx);
02315                 if (ret < 0) {
02316                     av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
02317                     return ret;
02318                 }
02319 
02320                 /* we have a complete image: we try to decompress it */
02321                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
02322                     s2->pict_type = 0;
02323                 s2->first_slice = 1;
02324                 last_code = PICTURE_START_CODE;
02325             } else {
02326                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
02327                 if (avctx->err_recognition & AV_EF_EXPLODE)
02328                     return AVERROR_INVALIDDATA;
02329             }
02330             break;
02331         case EXT_START_CODE:
02332             init_get_bits(&s2->gb, buf_ptr, input_size*8);
02333 
02334             switch (get_bits(&s2->gb, 4)) {
02335             case 0x1:
02336                 if (last_code == 0) {
02337                 mpeg_decode_sequence_extension(s);
02338                 } else {
02339                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
02340                     if (avctx->err_recognition & AV_EF_EXPLODE)
02341                         return AVERROR_INVALIDDATA;
02342                 }
02343                 break;
02344             case 0x2:
02345                 mpeg_decode_sequence_display_extension(s);
02346                 break;
02347             case 0x3:
02348                 mpeg_decode_quant_matrix_extension(s2);
02349                 break;
02350             case 0x7:
02351                 mpeg_decode_picture_display_extension(s);
02352                 break;
02353             case 0x8:
02354                 if (last_code == PICTURE_START_CODE) {
02355                     mpeg_decode_picture_coding_extension(s);
02356                 } else {
02357                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
02358                     if (avctx->err_recognition & AV_EF_EXPLODE)
02359                         return AVERROR_INVALIDDATA;
02360                 }
02361                 break;
02362             }
02363             break;
02364         case USER_START_CODE:
02365             mpeg_decode_user_data(avctx, buf_ptr, input_size);
02366             break;
02367         case GOP_START_CODE:
02368             if (last_code == 0) {
02369                 s2->first_field=0;
02370                 mpeg_decode_gop(avctx, buf_ptr, input_size);
02371                 s->sync=1;
02372             } else {
02373                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
02374                 if (avctx->err_recognition & AV_EF_EXPLODE)
02375                     return AVERROR_INVALIDDATA;
02376             }
02377             break;
02378         default:
02379             if (start_code >= SLICE_MIN_START_CODE &&
02380                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
02381                 const int field_pic = s2->picture_structure != PICT_FRAME;
02382                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
02383                 last_code = SLICE_MIN_START_CODE;
02384 
02385                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
02386                     mb_y++;
02387 
02388                 if (mb_y >= s2->mb_height) {
02389                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
02390                     return -1;
02391                 }
02392 
02393                 if (s2->last_picture_ptr == NULL) {
02394                 /* Skip B-frames if we do not have reference frames and gop is not closed */
02395                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
02396                         if (!s->closed_gop)
02397                             break;
02398                     }
02399                 }
02400                 if (s2->pict_type == AV_PICTURE_TYPE_I)
02401                     s->sync=1;
02402                 if (s2->next_picture_ptr == NULL) {
02403                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
02404                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) break;
02405                 }
02406                 if ((avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type == AV_PICTURE_TYPE_B) ||
02407                     (avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type != AV_PICTURE_TYPE_I) ||
02408                      avctx->skip_frame >= AVDISCARD_ALL)
02409                     break;
02410 
02411                 if (!s->mpeg_enc_ctx_allocated)
02412                     break;
02413 
02414                 if (s2->codec_id == CODEC_ID_MPEG2VIDEO) {
02415                     if (mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
02416                         break;
02417                 }
02418 
02419                 if (!s2->pict_type) {
02420                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
02421                     if (avctx->err_recognition & AV_EF_EXPLODE)
02422                         return AVERROR_INVALIDDATA;
02423                     break;
02424                 }
02425 
02426                 if (s2->first_slice) {
02427                     s2->first_slice = 0;
02428                     if (mpeg_field_start(s2, buf, buf_size) < 0)
02429                         return -1;
02430                 }
02431                 if (!s2->current_picture_ptr) {
02432                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
02433                     return AVERROR_INVALIDDATA;
02434                 }
02435 
02436                 if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
02437                     s->slice_count++;
02438                     break;
02439                 }
02440 
02441                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
02442                     int threshold = (s2->mb_height * s->slice_count +
02443                                      s2->slice_context_count / 2) /
02444                                     s2->slice_context_count;
02445                     if (threshold <= mb_y) {
02446                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
02447 
02448                         thread_context->start_mb_y = mb_y;
02449                         thread_context->end_mb_y   = s2->mb_height;
02450                         if (s->slice_count) {
02451                             s2->thread_context[s->slice_count-1]->end_mb_y = mb_y;
02452                             ff_update_duplicate_context(thread_context, s2);
02453                         }
02454                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
02455                         s->slice_count++;
02456                     }
02457                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
02458                 } else {
02459                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
02460                     emms_c();
02461 
02462                     if (ret < 0) {
02463                         if (avctx->err_recognition & AV_EF_EXPLODE)
02464                             return ret;
02465                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
02466                             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);
02467                     } else {
02468                         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);
02469                     }
02470                 }
02471             }
02472             break;
02473         }
02474     }
02475 }
02476 
02477 static void flush(AVCodecContext *avctx)
02478 {
02479     Mpeg1Context *s = avctx->priv_data;
02480 
02481     s->sync=0;
02482     s->closed_gop = 0;
02483 
02484     ff_mpeg_flush(avctx);
02485 }
02486 
02487 static int mpeg_decode_end(AVCodecContext *avctx)
02488 {
02489     Mpeg1Context *s = avctx->priv_data;
02490 
02491     if (s->mpeg_enc_ctx_allocated)
02492         MPV_common_end(&s->mpeg_enc_ctx);
02493     return 0;
02494 }
02495 
02496 static const AVProfile mpeg2_video_profiles[] = {
02497     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
02498     { FF_PROFILE_MPEG2_HIGH,         "High"               },
02499     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
02500     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
02501     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
02502     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
02503     { FF_PROFILE_RESERVED,           "Reserved"           },
02504     { FF_PROFILE_RESERVED,           "Reserved"           },
02505     { FF_PROFILE_UNKNOWN },
02506 };
02507 
02508 
02509 AVCodec ff_mpeg1video_decoder = {
02510     .name           = "mpeg1video",
02511     .type           = AVMEDIA_TYPE_VIDEO,
02512     .id             = CODEC_ID_MPEG1VIDEO,
02513     .priv_data_size = sizeof(Mpeg1Context),
02514     .init           = mpeg_decode_init,
02515     .close          = mpeg_decode_end,
02516     .decode         = mpeg_decode_frame,
02517     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
02518     .flush          = flush,
02519     .max_lowres     = 3,
02520     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
02521     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
02522 };
02523 
02524 AVCodec ff_mpeg2video_decoder = {
02525     .name           = "mpeg2video",
02526     .type           = AVMEDIA_TYPE_VIDEO,
02527     .id             = CODEC_ID_MPEG2VIDEO,
02528     .priv_data_size = sizeof(Mpeg1Context),
02529     .init           = mpeg_decode_init,
02530     .close          = mpeg_decode_end,
02531     .decode         = mpeg_decode_frame,
02532     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
02533     .flush          = flush,
02534     .max_lowres     = 3,
02535     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
02536     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
02537 };
02538 
02539 #if CONFIG_MPEG_XVMC_DECODER
02540 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
02541 {
02542     if (avctx->active_thread_type & FF_THREAD_SLICE)
02543         return -1;
02544     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
02545         return -1;
02546     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
02547         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
02548     }
02549     mpeg_decode_init(avctx);
02550 
02551     avctx->pix_fmt           = PIX_FMT_XVMC_MPEG2_IDCT;
02552     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
02553 
02554     return 0;
02555 }
02556 
02557 AVCodec ff_mpeg_xvmc_decoder = {
02558     .name           = "mpegvideo_xvmc",
02559     .type           = AVMEDIA_TYPE_VIDEO,
02560     .id             = CODEC_ID_MPEG2VIDEO_XVMC,
02561     .priv_data_size = sizeof(Mpeg1Context),
02562     .init           = mpeg_mc_decode_init,
02563     .close          = mpeg_decode_end,
02564     .decode         = mpeg_decode_frame,
02565     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
02566     .flush          = flush,
02567     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
02568 };
02569 
02570 #endif
02571 
02572 #if CONFIG_MPEG_VDPAU_DECODER
02573 AVCodec ff_mpeg_vdpau_decoder = {
02574     .name           = "mpegvideo_vdpau",
02575     .type           = AVMEDIA_TYPE_VIDEO,
02576     .id             = CODEC_ID_MPEG2VIDEO,
02577     .priv_data_size = sizeof(Mpeg1Context),
02578     .init           = mpeg_decode_init,
02579     .close          = mpeg_decode_end,
02580     .decode         = mpeg_decode_frame,
02581     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
02582     .flush          = flush,
02583     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
02584 };
02585 #endif
02586 
02587 #if CONFIG_MPEG1_VDPAU_DECODER
02588 AVCodec ff_mpeg1_vdpau_decoder = {
02589     .name           = "mpeg1video_vdpau",
02590     .type           = AVMEDIA_TYPE_VIDEO,
02591     .id             = CODEC_ID_MPEG1VIDEO,
02592     .priv_data_size = sizeof(Mpeg1Context),
02593     .init           = mpeg_decode_init,
02594     .close          = mpeg_decode_end,
02595     .decode         = mpeg_decode_frame,
02596     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
02597     .flush          = flush,
02598     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
02599 };
02600 #endif
02601