]> git.sesse.net Git - ffmpeg/blob - libavcodec/mpeg12.c
Merge commit 'd9a2e87b1ce44cce23801e7ec6810f8bf994fa23'
[ffmpeg] / libavcodec / mpeg12.c
1 /*
2  * MPEG-1/2 decoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22
23 /**
24  * @file
25  * MPEG-1/2 decoder
26  */
27
28 #define UNCHECKED_BITSTREAM_READER 1
29
30 //#define DEBUG
31 #include "internal.h"
32 #include "avcodec.h"
33 #include "dsputil.h"
34 #include "mpegvideo.h"
35 #include "libavutil/avassert.h"
36 #include "libavutil/timecode.h"
37
38 #include "mpeg12.h"
39 #include "mpeg12data.h"
40 #include "mpeg12decdata.h"
41 #include "bytestream.h"
42 #include "vdpau_internal.h"
43 #include "xvmc_internal.h"
44 #include "thread.h"
45
46
47 #define MV_VLC_BITS 9
48 #define MBINCR_VLC_BITS 9
49 #define MB_PAT_VLC_BITS 9
50 #define MB_PTYPE_VLC_BITS 6
51 #define MB_BTYPE_VLC_BITS 6
52
53 static VLC mv_vlc;
54
55 /* as H.263, but only 17 codes */
56 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
57 {
58     int code, sign, val, shift;
59
60     code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
61     if (code == 0) {
62         return pred;
63     }
64     if (code < 0) {
65         return 0xffff;
66     }
67
68     sign  = get_bits1(&s->gb);
69     shift = fcode - 1;
70     val   = code;
71     if (shift) {
72         val  = (val - 1) << shift;
73         val |= get_bits(&s->gb, shift);
74         val++;
75     }
76     if (sign)
77         val = -val;
78     val += pred;
79
80     /* modulo decoding */
81     return sign_extend(val, 5 + shift);
82 }
83
84 static inline int mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
85 {
86     int level, dc, diff, i, j, run;
87     int component;
88     RLTable *rl = &ff_rl_mpeg1;
89     uint8_t * const scantable    = s->intra_scantable.permutated;
90     const uint16_t *quant_matrix = s->intra_matrix;
91     const int qscale             = s->qscale;
92
93     /* DC coefficient */
94     component = (n <= 3 ? 0 : n - 4 + 1);
95     diff = decode_dc(&s->gb, component);
96     if (diff >= 0xffff)
97         return -1;
98     dc  = s->last_dc[component];
99     dc += diff;
100     s->last_dc[component] = dc;
101     block[0] = dc * quant_matrix[0];
102     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
103     i = 0;
104     {
105         OPEN_READER(re, &s->gb);
106         /* now quantify & encode AC coefficients */
107         for (;;) {
108             UPDATE_CACHE(re, &s->gb);
109             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
110
111             if (level == 127) {
112                 break;
113             } else if (level != 0) {
114                 i += run;
115                 j = scantable[i];
116                 level = (level * qscale * quant_matrix[j]) >> 4;
117                 level = (level - 1) | 1;
118                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
119                 LAST_SKIP_BITS(re, &s->gb, 1);
120             } else {
121                 /* escape */
122                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
123                 UPDATE_CACHE(re, &s->gb);
124                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
125                 if (level == -128) {
126                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
127                 } else if (level == 0) {
128                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
129                 }
130                 i += run;
131                 j = scantable[i];
132                 if (level < 0) {
133                     level = -level;
134                     level = (level * qscale * quant_matrix[j]) >> 4;
135                     level = (level - 1) | 1;
136                     level = -level;
137                 } else {
138                     level = (level * qscale * quant_matrix[j]) >> 4;
139                     level = (level - 1) | 1;
140                 }
141             }
142             if (i > 63) {
143                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
144                 return -1;
145             }
146
147             block[j] = level;
148         }
149         CLOSE_READER(re, &s->gb);
150     }
151     s->block_last_index[n] = i;
152    return 0;
153 }
154
155 int ff_mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
156 {
157     return mpeg1_decode_block_intra(s, block, n);
158 }
159
160 static inline int mpeg1_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
161 {
162     int level, i, j, run;
163     RLTable *rl = &ff_rl_mpeg1;
164     uint8_t * const scantable    = s->intra_scantable.permutated;
165     const uint16_t *quant_matrix = s->inter_matrix;
166     const int qscale             = s->qscale;
167
168     {
169         OPEN_READER(re, &s->gb);
170         i = -1;
171         // special case for first coefficient, no need to add second VLC table
172         UPDATE_CACHE(re, &s->gb);
173         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
174             level = (3 * qscale * quant_matrix[0]) >> 5;
175             level = (level - 1) | 1;
176             if (GET_CACHE(re, &s->gb) & 0x40000000)
177                 level = -level;
178             block[0] = level;
179             i++;
180             SKIP_BITS(re, &s->gb, 2);
181             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
182                 goto end;
183         }
184         /* now quantify & encode AC coefficients */
185         for (;;) {
186             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
187
188             if (level != 0) {
189                 i += run;
190                 j = scantable[i];
191                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
192                 level = (level - 1) | 1;
193                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
194                 SKIP_BITS(re, &s->gb, 1);
195             } else {
196                 /* escape */
197                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
198                 UPDATE_CACHE(re, &s->gb);
199                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
200                 if (level == -128) {
201                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
202                 } else if (level == 0) {
203                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
204                 }
205                 i += run;
206                 j = scantable[i];
207                 if (level < 0) {
208                     level = -level;
209                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
210                     level = (level - 1) | 1;
211                     level = -level;
212                 } else {
213                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
214                     level = (level - 1) | 1;
215                 }
216             }
217             if (i > 63) {
218                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
219                 return -1;
220             }
221
222             block[j] = level;
223             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
224                 break;
225             UPDATE_CACHE(re, &s->gb);
226         }
227 end:
228         LAST_SKIP_BITS(re, &s->gb, 2);
229         CLOSE_READER(re, &s->gb);
230     }
231     s->block_last_index[n] = i;
232     return 0;
233 }
234
235 /**
236  * Note: this function can read out of range and crash for corrupt streams.
237  * Changing this would eat up any speed benefits it has.
238  * Do not use "fast" flag if you need the code to be robust.
239  */
240 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
241 {
242     int level, i, j, run;
243     RLTable *rl = &ff_rl_mpeg1;
244     uint8_t * const scantable = s->intra_scantable.permutated;
245     const int qscale          = s->qscale;
246
247     {
248         OPEN_READER(re, &s->gb);
249         i = -1;
250         // special case for first coefficient, no need to add second VLC table
251         UPDATE_CACHE(re, &s->gb);
252         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
253             level = (3 * qscale) >> 1;
254             level = (level - 1) | 1;
255             if (GET_CACHE(re, &s->gb) & 0x40000000)
256                 level = -level;
257             block[0] = level;
258             i++;
259             SKIP_BITS(re, &s->gb, 2);
260             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
261                 goto end;
262         }
263
264         /* now quantify & encode AC coefficients */
265         for (;;) {
266             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
267
268             if (level != 0) {
269                 i += run;
270                 j = scantable[i];
271                 level = ((level * 2 + 1) * qscale) >> 1;
272                 level = (level - 1) | 1;
273                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
274                 SKIP_BITS(re, &s->gb, 1);
275             } else {
276                 /* escape */
277                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
278                 UPDATE_CACHE(re, &s->gb);
279                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
280                 if (level == -128) {
281                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
282                 } else if (level == 0) {
283                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
284                 }
285                 i += run;
286                 j = scantable[i];
287                 if (level < 0) {
288                     level = -level;
289                     level = ((level * 2 + 1) * qscale) >> 1;
290                     level = (level - 1) | 1;
291                     level = -level;
292                 } else {
293                     level = ((level * 2 + 1) * qscale) >> 1;
294                     level = (level - 1) | 1;
295                 }
296             }
297
298             block[j] = level;
299             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
300                 break;
301             UPDATE_CACHE(re, &s->gb);
302         }
303 end:
304         LAST_SKIP_BITS(re, &s->gb, 2);
305         CLOSE_READER(re, &s->gb);
306     }
307     s->block_last_index[n] = i;
308     return 0;
309 }
310
311
312 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n)
313 {
314     int level, i, j, run;
315     RLTable *rl = &ff_rl_mpeg1;
316     uint8_t * const scantable = s->intra_scantable.permutated;
317     const uint16_t *quant_matrix;
318     const int qscale = s->qscale;
319     int mismatch;
320
321     mismatch = 1;
322
323     {
324         OPEN_READER(re, &s->gb);
325         i = -1;
326         if (n < 4)
327             quant_matrix = s->inter_matrix;
328         else
329             quant_matrix = s->chroma_inter_matrix;
330
331         // special case for first coefficient, no need to add second VLC table
332         UPDATE_CACHE(re, &s->gb);
333         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
334             level= (3 * qscale * quant_matrix[0]) >> 5;
335             if (GET_CACHE(re, &s->gb) & 0x40000000)
336                 level = -level;
337             block[0]  = level;
338             mismatch ^= level;
339             i++;
340             SKIP_BITS(re, &s->gb, 2);
341             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
342                 goto end;
343         }
344
345         /* now quantify & encode AC coefficients */
346         for (;;) {
347             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
348
349             if (level != 0) {
350                 i += run;
351                 j = scantable[i];
352                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
353                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
354                 SKIP_BITS(re, &s->gb, 1);
355             } else {
356                 /* escape */
357                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
358                 UPDATE_CACHE(re, &s->gb);
359                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
360
361                 i += run;
362                 j = scantable[i];
363                 if (level < 0) {
364                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
365                     level = -level;
366                 } else {
367                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
368                 }
369             }
370             if (i > 63) {
371                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
372                 return -1;
373             }
374
375             mismatch ^= level;
376             block[j]  = level;
377             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
378                 break;
379             UPDATE_CACHE(re, &s->gb);
380         }
381 end:
382         LAST_SKIP_BITS(re, &s->gb, 2);
383         CLOSE_READER(re, &s->gb);
384     }
385     block[63] ^= (mismatch & 1);
386
387     s->block_last_index[n] = i;
388     return 0;
389 }
390
391 /**
392  * Note: this function can read out of range and crash for corrupt streams.
393  * Changing this would eat up any speed benefits it has.
394  * Do not use "fast" flag if you need the code to be robust.
395  */
396 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
397                                                     DCTELEM *block, int n)
398 {
399     int level, i, j, run;
400     RLTable *rl = &ff_rl_mpeg1;
401     uint8_t * const scantable = s->intra_scantable.permutated;
402     const int qscale          = s->qscale;
403     OPEN_READER(re, &s->gb);
404     i = -1;
405
406     // special case for first coefficient, no need to add second VLC table
407     UPDATE_CACHE(re, &s->gb);
408     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
409         level = (3 * qscale) >> 1;
410         if (GET_CACHE(re, &s->gb) & 0x40000000)
411             level = -level;
412         block[0] = level;
413         i++;
414         SKIP_BITS(re, &s->gb, 2);
415         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
416             goto end;
417     }
418
419     /* now quantify & encode AC coefficients */
420     for (;;) {
421         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
422
423         if (level != 0) {
424             i += run;
425             j  = scantable[i];
426             level = ((level * 2 + 1) * qscale) >> 1;
427             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
428             SKIP_BITS(re, &s->gb, 1);
429         } else {
430             /* escape */
431             run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
432             UPDATE_CACHE(re, &s->gb);
433             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
434
435             i += run;
436             j  = scantable[i];
437             if (level < 0) {
438                 level = ((-level * 2 + 1) * qscale) >> 1;
439                 level = -level;
440             } else {
441                 level = ((level * 2 + 1) * qscale) >> 1;
442             }
443         }
444
445         block[j] = level;
446         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
447             break;
448         UPDATE_CACHE(re, &s->gb);
449     }
450 end:
451     LAST_SKIP_BITS(re, &s->gb, 2);
452     CLOSE_READER(re, &s->gb);
453     s->block_last_index[n] = i;
454     return 0;
455 }
456
457
458 static inline int mpeg2_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
459 {
460     int level, dc, diff, i, j, run;
461     int component;
462     RLTable *rl;
463     uint8_t * const scantable = s->intra_scantable.permutated;
464     const uint16_t *quant_matrix;
465     const int qscale = s->qscale;
466     int mismatch;
467
468     /* DC coefficient */
469     if (n < 4) {
470         quant_matrix = s->intra_matrix;
471         component = 0;
472     } else {
473         quant_matrix = s->chroma_intra_matrix;
474         component = (n & 1) + 1;
475     }
476     diff = decode_dc(&s->gb, component);
477     if (diff >= 0xffff)
478         return -1;
479     dc  = s->last_dc[component];
480     dc += diff;
481     s->last_dc[component] = dc;
482     block[0] = dc << (3 - s->intra_dc_precision);
483     av_dlog(s->avctx, "dc=%d\n", block[0]);
484     mismatch = block[0] ^ 1;
485     i = 0;
486     if (s->intra_vlc_format)
487         rl = &ff_rl_mpeg2;
488     else
489         rl = &ff_rl_mpeg1;
490
491     {
492         OPEN_READER(re, &s->gb);
493         /* now quantify & encode AC coefficients */
494         for (;;) {
495             UPDATE_CACHE(re, &s->gb);
496             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
497
498             if (level == 127) {
499                 break;
500             } else if (level != 0) {
501                 i += run;
502                 j  = scantable[i];
503                 level = (level * qscale * quant_matrix[j]) >> 4;
504                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
505                 LAST_SKIP_BITS(re, &s->gb, 1);
506             } else {
507                 /* escape */
508                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
509                 UPDATE_CACHE(re, &s->gb);
510                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
511                 i += run;
512                 j  = scantable[i];
513                 if (level < 0) {
514                     level = (-level * qscale * quant_matrix[j]) >> 4;
515                     level = -level;
516                 } else {
517                     level = (level * qscale * quant_matrix[j]) >> 4;
518                 }
519             }
520             if (i > 63) {
521                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
522                 return -1;
523             }
524
525             mismatch ^= level;
526             block[j]  = level;
527         }
528         CLOSE_READER(re, &s->gb);
529     }
530     block[63] ^= mismatch & 1;
531
532     s->block_last_index[n] = i;
533     return 0;
534 }
535
536 /**
537  * Note: this function can read out of range and crash for corrupt streams.
538  * Changing this would eat up any speed benefits it has.
539  * Do not use "fast" flag if you need the code to be robust.
540  */
541 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n)
542 {
543     int level, dc, diff, j, run;
544     int component;
545     RLTable *rl;
546     uint8_t * scantable = s->intra_scantable.permutated;
547     const uint16_t *quant_matrix;
548     const int qscale = s->qscale;
549
550     /* DC coefficient */
551     if (n < 4) {
552         quant_matrix = s->intra_matrix;
553         component = 0;
554     } else {
555         quant_matrix = s->chroma_intra_matrix;
556         component = (n & 1) + 1;
557     }
558     diff = decode_dc(&s->gb, component);
559     if (diff >= 0xffff)
560         return -1;
561     dc = s->last_dc[component];
562     dc += diff;
563     s->last_dc[component] = dc;
564     block[0] = dc << (3 - s->intra_dc_precision);
565     if (s->intra_vlc_format)
566         rl = &ff_rl_mpeg2;
567     else
568         rl = &ff_rl_mpeg1;
569
570     {
571         OPEN_READER(re, &s->gb);
572         /* now quantify & encode AC coefficients */
573         for (;;) {
574             UPDATE_CACHE(re, &s->gb);
575             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
576
577             if (level == 127) {
578                 break;
579             } else if (level != 0) {
580                 scantable += run;
581                 j = *scantable;
582                 level = (level * qscale * quant_matrix[j]) >> 4;
583                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
584                 LAST_SKIP_BITS(re, &s->gb, 1);
585             } else {
586                 /* escape */
587                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
588                 UPDATE_CACHE(re, &s->gb);
589                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
590                 scantable += run;
591                 j = *scantable;
592                 if (level < 0) {
593                     level = (-level * qscale * quant_matrix[j]) >> 4;
594                     level = -level;
595                 } else {
596                     level = (level * qscale * quant_matrix[j]) >> 4;
597                 }
598             }
599
600             block[j] = level;
601         }
602         CLOSE_READER(re, &s->gb);
603     }
604
605     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
606     return 0;
607 }
608
609 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
610
611 #define INIT_2D_VLC_RL(rl, static_size)\
612 {\
613     static RL_VLC_ELEM rl_vlc_table[static_size];\
614     INIT_VLC_STATIC(&rl.vlc, TEX_VLC_BITS, rl.n + 2,\
615                     &rl.table_vlc[0][1], 4, 2,\
616                     &rl.table_vlc[0][0], 4, 2, static_size);\
617 \
618     rl.rl_vlc[0] = rl_vlc_table;\
619     init_2d_vlc_rl(&rl);\
620 }
621
622 static void init_2d_vlc_rl(RLTable *rl)
623 {
624     int i;
625
626     for (i = 0; i < rl->vlc.table_size; i++) {
627         int code = rl->vlc.table[i][0];
628         int len  = rl->vlc.table[i][1];
629         int level, run;
630
631         if (len == 0) { // illegal code
632             run   = 65;
633             level = MAX_LEVEL;
634         } else if (len<0) { //more bits needed
635             run   = 0;
636             level = code;
637         } else {
638             if (code == rl->n) { //esc
639                 run   = 65;
640                 level = 0;
641             } else if (code == rl->n+1) { //eob
642                 run   = 0;
643                 level = 127;
644             } else {
645                 run   = rl->table_run  [code] + 1;
646                 level = rl->table_level[code];
647             }
648         }
649         rl->rl_vlc[0][i].len   = len;
650         rl->rl_vlc[0][i].level = level;
651         rl->rl_vlc[0][i].run   = run;
652     }
653 }
654
655 void ff_mpeg12_common_init(MpegEncContext *s)
656 {
657
658     s->y_dc_scale_table =
659     s->c_dc_scale_table = ff_mpeg2_dc_scale_table[s->intra_dc_precision];
660
661 }
662
663 void ff_mpeg1_clean_buffers(MpegEncContext *s)
664 {
665     s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
666     s->last_dc[1] = s->last_dc[0];
667     s->last_dc[2] = s->last_dc[0];
668     memset(s->last_mv, 0, sizeof(s->last_mv));
669 }
670
671
672 /******************************************/
673 /* decoding */
674
675 VLC ff_dc_lum_vlc;
676 VLC ff_dc_chroma_vlc;
677
678 static VLC mbincr_vlc;
679 static VLC mb_ptype_vlc;
680 static VLC mb_btype_vlc;
681 static VLC mb_pat_vlc;
682
683 av_cold void ff_mpeg12_init_vlcs(void)
684 {
685     static int done = 0;
686
687     if (!done) {
688         done = 1;
689
690         INIT_VLC_STATIC(&ff_dc_lum_vlc, DC_VLC_BITS, 12,
691                         ff_mpeg12_vlc_dc_lum_bits, 1, 1,
692                         ff_mpeg12_vlc_dc_lum_code, 2, 2, 512);
693         INIT_VLC_STATIC(&ff_dc_chroma_vlc,  DC_VLC_BITS, 12,
694                         ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
695                         ff_mpeg12_vlc_dc_chroma_code, 2, 2, 514);
696         INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 17,
697                         &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
698                         &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 518);
699         INIT_VLC_STATIC(&mbincr_vlc, MBINCR_VLC_BITS, 36,
700                         &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
701                         &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 538);
702         INIT_VLC_STATIC(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
703                         &ff_mpeg12_mbPatTable[0][1], 2, 1,
704                         &ff_mpeg12_mbPatTable[0][0], 2, 1, 512);
705
706         INIT_VLC_STATIC(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
707                         &table_mb_ptype[0][1], 2, 1,
708                         &table_mb_ptype[0][0], 2, 1, 64);
709         INIT_VLC_STATIC(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
710                         &table_mb_btype[0][1], 2, 1,
711                         &table_mb_btype[0][0], 2, 1, 64);
712         ff_init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
713         ff_init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
714
715         INIT_2D_VLC_RL(ff_rl_mpeg1, 680);
716         INIT_2D_VLC_RL(ff_rl_mpeg2, 674);
717     }
718 }
719
720 static inline int get_dmv(MpegEncContext *s)
721 {
722     if (get_bits1(&s->gb))
723         return 1 - (get_bits1(&s->gb) << 1);
724     else
725         return 0;
726 }
727
728 static inline int get_qscale(MpegEncContext *s)
729 {
730     int qscale = get_bits(&s->gb, 5);
731     if (s->q_scale_type) {
732         return non_linear_qscale[qscale];
733     } else {
734         return qscale << 1;
735     }
736 }
737
738 static void exchange_uv(MpegEncContext *s)
739 {
740     DCTELEM (*tmp)[64];
741
742     tmp           = s->pblocks[4];
743     s->pblocks[4] = s->pblocks[5];
744     s->pblocks[5] = tmp;
745 }
746
747 /* motion type (for MPEG-2) */
748 #define MT_FIELD 1
749 #define MT_FRAME 2
750 #define MT_16X8  2
751 #define MT_DMV   3
752
753 static int mpeg_decode_mb(MpegEncContext *s, DCTELEM block[12][64])
754 {
755     int i, j, k, cbp, val, mb_type, motion_type;
756     const int mb_block_count = 4 + (1 << s->chroma_format);
757
758     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
759
760     av_assert2(s->mb_skipped == 0);
761
762     if (s->mb_skip_run-- != 0) {
763         if (s->pict_type == AV_PICTURE_TYPE_P) {
764             s->mb_skipped = 1;
765             s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
766         } else {
767             int mb_type;
768
769             if (s->mb_x)
770                 mb_type = s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
771             else
772                 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
773             if (IS_INTRA(mb_type))
774                 return -1;
775             s->current_picture.f.mb_type[s->mb_x + s->mb_y*s->mb_stride] =
776                 mb_type | MB_TYPE_SKIP;
777 //            av_assert2(s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
778
779             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
780                 s->mb_skipped = 1;
781         }
782
783         return 0;
784     }
785
786     switch (s->pict_type) {
787     default:
788     case AV_PICTURE_TYPE_I:
789         if (get_bits1(&s->gb) == 0) {
790             if (get_bits1(&s->gb) == 0) {
791                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
792                 return -1;
793             }
794             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
795         } else {
796             mb_type = MB_TYPE_INTRA;
797         }
798         break;
799     case AV_PICTURE_TYPE_P:
800         mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
801         if (mb_type < 0) {
802             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
803             return -1;
804         }
805         mb_type = ptype2mb_type[mb_type];
806         break;
807     case AV_PICTURE_TYPE_B:
808         mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
809         if (mb_type < 0) {
810             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
811             return -1;
812         }
813         mb_type = btype2mb_type[mb_type];
814         break;
815     }
816     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
817 //    motion_type = 0; /* avoid warning */
818     if (IS_INTRA(mb_type)) {
819         s->dsp.clear_blocks(s->block[0]);
820
821         if (!s->chroma_y_shift) {
822             s->dsp.clear_blocks(s->block[6]);
823         }
824
825         /* compute DCT type */
826         if (s->picture_structure == PICT_FRAME && // FIXME add an interlaced_dct coded var?
827             !s->frame_pred_frame_dct) {
828             s->interlaced_dct = get_bits1(&s->gb);
829         }
830
831         if (IS_QUANT(mb_type))
832             s->qscale = get_qscale(s);
833
834         if (s->concealment_motion_vectors) {
835             /* just parse them */
836             if (s->picture_structure != PICT_FRAME)
837                 skip_bits1(&s->gb); /* field select */
838
839             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
840                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
841             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
842                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
843
844             skip_bits1(&s->gb); /* marker */
845         } else
846             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
847         s->mb_intra = 1;
848         // if 1, we memcpy blocks in xvmcvideo
849         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
850             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
851             if (s->swap_uv) {
852                 exchange_uv(s);
853             }
854         }
855
856         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
857             if (s->flags2 & CODEC_FLAG2_FAST) {
858                 for (i = 0; i < 6; i++) {
859                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
860                 }
861             } else {
862                 for (i = 0; i < mb_block_count; i++) {
863                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
864                         return -1;
865                 }
866             }
867         } else {
868             for (i = 0; i < 6; i++) {
869                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
870                     return -1;
871             }
872         }
873     } else {
874         if (mb_type & MB_TYPE_ZERO_MV) {
875             av_assert2(mb_type & MB_TYPE_CBP);
876
877             s->mv_dir = MV_DIR_FORWARD;
878             if (s->picture_structure == PICT_FRAME) {
879                 if (!s->frame_pred_frame_dct)
880                     s->interlaced_dct = get_bits1(&s->gb);
881                 s->mv_type = MV_TYPE_16X16;
882             } else {
883                 s->mv_type = MV_TYPE_FIELD;
884                 mb_type |= MB_TYPE_INTERLACED;
885                 s->field_select[0][0] = s->picture_structure - 1;
886             }
887
888             if (IS_QUANT(mb_type))
889                 s->qscale = get_qscale(s);
890
891             s->last_mv[0][0][0] = 0;
892             s->last_mv[0][0][1] = 0;
893             s->last_mv[0][1][0] = 0;
894             s->last_mv[0][1][1] = 0;
895             s->mv[0][0][0] = 0;
896             s->mv[0][0][1] = 0;
897         } else {
898             av_assert2(mb_type & MB_TYPE_L0L1);
899             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
900             /* get additional motion vector type */
901             if (s->frame_pred_frame_dct)
902                 motion_type = MT_FRAME;
903             else {
904                 motion_type = get_bits(&s->gb, 2);
905                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
906                     s->interlaced_dct = get_bits1(&s->gb);
907             }
908
909             if (IS_QUANT(mb_type))
910                 s->qscale = get_qscale(s);
911
912             /* motion vectors */
913             s->mv_dir = (mb_type >> 13) & 3;
914             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
915             switch (motion_type) {
916             case MT_FRAME: /* or MT_16X8 */
917                 if (s->picture_structure == PICT_FRAME) {
918                     mb_type |= MB_TYPE_16x16;
919                     s->mv_type = MV_TYPE_16X16;
920                     for (i = 0; i < 2; i++) {
921                         if (USES_LIST(mb_type, i)) {
922                             /* MT_FRAME */
923                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
924                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
925                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
926                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
927                             /* full_pel: only for MPEG-1 */
928                             if (s->full_pel[i]) {
929                                 s->mv[i][0][0] <<= 1;
930                                 s->mv[i][0][1] <<= 1;
931                             }
932                         }
933                     }
934                 } else {
935                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
936                     s->mv_type = MV_TYPE_16X8;
937                     for (i = 0; i < 2; i++) {
938                         if (USES_LIST(mb_type, i)) {
939                             /* MT_16X8 */
940                             for (j = 0; j < 2; j++) {
941                                 s->field_select[i][j] = get_bits1(&s->gb);
942                                 for (k = 0; k < 2; k++) {
943                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
944                                                              s->last_mv[i][j][k]);
945                                     s->last_mv[i][j][k] = val;
946                                     s->mv[i][j][k]      = val;
947                                 }
948                             }
949                         }
950                     }
951                 }
952                 break;
953             case MT_FIELD:
954                 s->mv_type = MV_TYPE_FIELD;
955                 if (s->picture_structure == PICT_FRAME) {
956                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
957                     for (i = 0; i < 2; i++) {
958                         if (USES_LIST(mb_type, i)) {
959                             for (j = 0; j < 2; j++) {
960                                 s->field_select[i][j] = get_bits1(&s->gb);
961                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
962                                                          s->last_mv[i][j][0]);
963                                 s->last_mv[i][j][0] = val;
964                                 s->mv[i][j][0]      = val;
965                                 av_dlog(s->avctx, "fmx=%d\n", val);
966                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
967                                                          s->last_mv[i][j][1] >> 1);
968                                 s->last_mv[i][j][1] = val << 1;
969                                 s->mv[i][j][1]      = val;
970                                 av_dlog(s->avctx, "fmy=%d\n", val);
971                             }
972                         }
973                     }
974                 } else {
975                     av_assert0(!s->progressive_sequence);
976                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
977                     for (i = 0; i < 2; i++) {
978                         if (USES_LIST(mb_type, i)) {
979                             s->field_select[i][0] = get_bits1(&s->gb);
980                             for (k = 0; k < 2; k++) {
981                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
982                                                          s->last_mv[i][0][k]);
983                                 s->last_mv[i][0][k] = val;
984                                 s->last_mv[i][1][k] = val;
985                                 s->mv[i][0][k]      = val;
986                             }
987                         }
988                     }
989                 }
990                 break;
991             case MT_DMV:
992                 if(s->progressive_sequence){
993                     av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
994                     return -1;
995                 }
996                 s->mv_type = MV_TYPE_DMV;
997                 for (i = 0; i < 2; i++) {
998                     if (USES_LIST(mb_type, i)) {
999                         int dmx, dmy, mx, my, m;
1000                         const int my_shift = s->picture_structure == PICT_FRAME;
1001
1002                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
1003                                                 s->last_mv[i][0][0]);
1004                         s->last_mv[i][0][0] = mx;
1005                         s->last_mv[i][1][0] = mx;
1006                         dmx = get_dmv(s);
1007                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1008                                                  s->last_mv[i][0][1] >> my_shift);
1009                         dmy = get_dmv(s);
1010
1011
1012                         s->last_mv[i][0][1] = my << my_shift;
1013                         s->last_mv[i][1][1] = my << my_shift;
1014
1015                         s->mv[i][0][0] = mx;
1016                         s->mv[i][0][1] = my;
1017                         s->mv[i][1][0] = mx; // not used
1018                         s->mv[i][1][1] = my; // not used
1019
1020                         if (s->picture_structure == PICT_FRAME) {
1021                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1022
1023                             // m = 1 + 2 * s->top_field_first;
1024                             m = s->top_field_first ? 1 : 3;
1025
1026                             /* top -> top pred */
1027                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1028                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1029                             m = 4 - m;
1030                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1031                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1032                         } else {
1033                             mb_type |= MB_TYPE_16x16;
1034
1035                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1036                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1037                             if (s->picture_structure == PICT_TOP_FIELD)
1038                                 s->mv[i][2][1]--;
1039                             else
1040                                 s->mv[i][2][1]++;
1041                         }
1042                     }
1043                 }
1044                 break;
1045             default:
1046                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1047                 return -1;
1048             }
1049         }
1050
1051         s->mb_intra = 0;
1052         if (HAS_CBP(mb_type)) {
1053             s->dsp.clear_blocks(s->block[0]);
1054
1055             cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1056             if (mb_block_count > 6) {
1057                  cbp <<= mb_block_count - 6;
1058                  cbp  |= get_bits(&s->gb, mb_block_count - 6);
1059                  s->dsp.clear_blocks(s->block[6]);
1060             }
1061             if (cbp <= 0) {
1062                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1063                 return -1;
1064             }
1065
1066             //if 1, we memcpy blocks in xvmcvideo
1067             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
1068                 ff_xvmc_pack_pblocks(s, cbp);
1069                 if (s->swap_uv) {
1070                     exchange_uv(s);
1071                 }
1072             }
1073
1074             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1075                 if (s->flags2 & CODEC_FLAG2_FAST) {
1076                     for (i = 0; i < 6; i++) {
1077                         if (cbp & 32) {
1078                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1079                         } else {
1080                             s->block_last_index[i] = -1;
1081                         }
1082                         cbp += cbp;
1083                     }
1084                 } else {
1085                     cbp <<= 12-mb_block_count;
1086
1087                     for (i = 0; i < mb_block_count; i++) {
1088                         if (cbp & (1 << 11)) {
1089                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
1090                                 return -1;
1091                         } else {
1092                             s->block_last_index[i] = -1;
1093                         }
1094                         cbp += cbp;
1095                     }
1096                 }
1097             } else {
1098                 if (s->flags2 & CODEC_FLAG2_FAST) {
1099                     for (i = 0; i < 6; i++) {
1100                         if (cbp & 32) {
1101                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1102                         } else {
1103                             s->block_last_index[i] = -1;
1104                         }
1105                         cbp += cbp;
1106                     }
1107                 } else {
1108                     for (i = 0; i < 6; i++) {
1109                         if (cbp & 32) {
1110                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
1111                                 return -1;
1112                         } else {
1113                             s->block_last_index[i] = -1;
1114                         }
1115                         cbp += cbp;
1116                     }
1117                 }
1118             }
1119         } else {
1120             for (i = 0; i < 12; i++)
1121                 s->block_last_index[i] = -1;
1122         }
1123     }
1124
1125     s->current_picture.f.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1126
1127     return 0;
1128 }
1129
1130 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1131 {
1132     Mpeg1Context *s = avctx->priv_data;
1133     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1134     int i;
1135
1136     /* we need some permutation to store matrices,
1137      * until MPV_common_init() sets the real permutation. */
1138     for (i = 0; i < 64; i++)
1139        s2->dsp.idct_permutation[i]=i;
1140
1141     ff_MPV_decode_defaults(s2);
1142
1143     s->mpeg_enc_ctx.avctx  = avctx;
1144     s->mpeg_enc_ctx.flags  = avctx->flags;
1145     s->mpeg_enc_ctx.flags2 = avctx->flags2;
1146     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1147     ff_mpeg12_init_vlcs();
1148
1149     s->mpeg_enc_ctx_allocated      = 0;
1150     s->mpeg_enc_ctx.picture_number = 0;
1151     s->repeat_field                = 0;
1152     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1153     avctx->color_range = AVCOL_RANGE_MPEG;
1154     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1155         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1156     else
1157         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1158     return 0;
1159 }
1160
1161 static int mpeg_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
1162 {
1163     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1164     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1165     int err;
1166
1167     if (avctx == avctx_from || !ctx_from->mpeg_enc_ctx_allocated || !s1->context_initialized)
1168         return 0;
1169
1170     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1171     if (err) return err;
1172
1173     if (!ctx->mpeg_enc_ctx_allocated)
1174         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1175
1176     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1177         s->picture_number++;
1178
1179     return 0;
1180 }
1181
1182 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1183                                  const uint8_t *new_perm)
1184 {
1185     uint16_t temp_matrix[64];
1186     int i;
1187
1188     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1189
1190     for (i = 0; i < 64; i++) {
1191         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1192     }
1193 }
1194
1195 static const enum PixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1196 #if CONFIG_MPEG_XVMC_DECODER
1197     PIX_FMT_XVMC_MPEG2_IDCT,
1198     PIX_FMT_XVMC_MPEG2_MC,
1199 #endif
1200 #if CONFIG_MPEG1_VDPAU_HWACCEL
1201     PIX_FMT_VDPAU_MPEG1,
1202 #endif
1203     PIX_FMT_YUV420P,
1204     PIX_FMT_NONE
1205 };
1206
1207 static const enum PixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1208 #if CONFIG_MPEG_XVMC_DECODER
1209     PIX_FMT_XVMC_MPEG2_IDCT,
1210     PIX_FMT_XVMC_MPEG2_MC,
1211 #endif
1212 #if CONFIG_MPEG2_VDPAU_HWACCEL
1213     PIX_FMT_VDPAU_MPEG2,
1214 #endif
1215 #if CONFIG_MPEG2_DXVA2_HWACCEL
1216     PIX_FMT_DXVA2_VLD,
1217 #endif
1218 #if CONFIG_MPEG2_VAAPI_HWACCEL
1219     PIX_FMT_VAAPI_VLD,
1220 #endif
1221     PIX_FMT_YUV420P,
1222     PIX_FMT_NONE
1223 };
1224
1225 static inline int uses_vdpau(AVCodecContext *avctx) {
1226     return avctx->pix_fmt == PIX_FMT_VDPAU_MPEG1 || avctx->pix_fmt == PIX_FMT_VDPAU_MPEG2;
1227 }
1228
1229 static enum PixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1230 {
1231     Mpeg1Context *s1 = avctx->priv_data;
1232     MpegEncContext *s = &s1->mpeg_enc_ctx;
1233
1234     if(s->chroma_format < 2) {
1235         enum PixelFormat res;
1236         res = avctx->get_format(avctx,
1237                                 avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1238                                 mpeg1_hwaccel_pixfmt_list_420 :
1239                                 mpeg2_hwaccel_pixfmt_list_420);
1240         if (res != PIX_FMT_XVMC_MPEG2_IDCT && res != PIX_FMT_XVMC_MPEG2_MC) {
1241             avctx->xvmc_acceleration = 0;
1242         } else if (!avctx->xvmc_acceleration) {
1243             avctx->xvmc_acceleration = 2;
1244         }
1245         return res;
1246     } else if(s->chroma_format == 2)
1247         return PIX_FMT_YUV422P;
1248     else
1249         return PIX_FMT_YUV444P;
1250 }
1251
1252 /* Call this function when we know all parameters.
1253  * It may be called in different places for MPEG-1 and MPEG-2. */
1254 static int mpeg_decode_postinit(AVCodecContext *avctx)
1255 {
1256     Mpeg1Context *s1 = avctx->priv_data;
1257     MpegEncContext *s = &s1->mpeg_enc_ctx;
1258     uint8_t old_permutation[64];
1259
1260     if ((s1->mpeg_enc_ctx_allocated == 0) ||
1261         avctx->coded_width  != s->width   ||
1262         avctx->coded_height != s->height  ||
1263         s1->save_width           != s->width                ||
1264         s1->save_height          != s->height               ||
1265         s1->save_aspect_info     != s->aspect_ratio_info    ||
1266         s1->save_progressive_seq != s->progressive_sequence ||
1267         0)
1268     {
1269
1270         if (s1->mpeg_enc_ctx_allocated) {
1271             ParseContext pc = s->parse_context;
1272             s->parse_context.buffer = 0;
1273             ff_MPV_common_end(s);
1274             s->parse_context = pc;
1275         }
1276
1277         if ((s->width == 0) || (s->height == 0))
1278             return -2;
1279
1280         avcodec_set_dimensions(avctx, s->width, s->height);
1281         avctx->bit_rate          = s->bit_rate;
1282         s1->save_aspect_info     = s->aspect_ratio_info;
1283         s1->save_width           = s->width;
1284         s1->save_height          = s->height;
1285         s1->save_progressive_seq = s->progressive_sequence;
1286
1287         /* low_delay may be forced, in this case we will have B-frames
1288          * that behave like P-frames. */
1289         avctx->has_b_frames = !s->low_delay;
1290
1291         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1292             //MPEG-1 fps
1293             avctx->time_base.den = avpriv_frame_rate_tab[s->frame_rate_index].num;
1294             avctx->time_base.num = avpriv_frame_rate_tab[s->frame_rate_index].den;
1295             //MPEG-1 aspect
1296             avctx->sample_aspect_ratio = av_d2q(1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1297             avctx->ticks_per_frame=1;
1298         } else {//MPEG-2
1299         //MPEG-2 fps
1300             av_reduce(&s->avctx->time_base.den,
1301                       &s->avctx->time_base.num,
1302                       avpriv_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
1303                       avpriv_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1304                       1 << 30);
1305             avctx->ticks_per_frame = 2;
1306             //MPEG-2 aspect
1307             if (s->aspect_ratio_info > 1) {
1308                 AVRational dar =
1309                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1310                                       (AVRational) {s1->pan_scan.width, s1->pan_scan.height}),
1311                              (AVRational) {s->width, s->height});
1312
1313                 // we ignore the spec here and guess a bit as reality does not match the spec, see for example
1314                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1315                 // issue1613, 621, 562
1316                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1317                    (av_cmp_q(dar, (AVRational) {4, 3}) && av_cmp_q(dar, (AVRational) {16, 9}))) {
1318                     s->avctx->sample_aspect_ratio =
1319                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1320                                  (AVRational) {s->width, s->height});
1321                 } else {
1322                     s->avctx->sample_aspect_ratio =
1323                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1324                                  (AVRational) {s1->pan_scan.width, s1->pan_scan.height});
1325 //issue1613 4/3 16/9 -> 16/9
1326 //res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1327 //widescreen-issue562.mpg 4/3 16/9 -> 16/9
1328 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1329 //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);
1330 //av_log(NULL, AV_LOG_ERROR, "B %d/%d\n", s->avctx->sample_aspect_ratio.num, s->avctx->sample_aspect_ratio.den);
1331                 }
1332             } else {
1333                 s->avctx->sample_aspect_ratio =
1334                     ff_mpeg2_aspect[s->aspect_ratio_info];
1335             }
1336         } // MPEG-2
1337
1338         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1339         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1340         // until then pix_fmt may be changed right after codec init
1341         if (avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT ||
1342             avctx->hwaccel )
1343             if (avctx->idct_algo == FF_IDCT_AUTO)
1344                 avctx->idct_algo = FF_IDCT_SIMPLE;
1345
1346         /* Quantization matrices may need reordering
1347          * if DCT permutation is changed. */
1348         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
1349
1350         if (ff_MPV_common_init(s) < 0)
1351             return -2;
1352
1353         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
1354         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->dsp.idct_permutation);
1355         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->dsp.idct_permutation);
1356         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->dsp.idct_permutation);
1357
1358         s1->mpeg_enc_ctx_allocated = 1;
1359     }
1360     return 0;
1361 }
1362
1363 static int mpeg1_decode_picture(AVCodecContext *avctx,
1364                                 const uint8_t *buf, int buf_size)
1365 {
1366     Mpeg1Context *s1 = avctx->priv_data;
1367     MpegEncContext *s = &s1->mpeg_enc_ctx;
1368     int ref, f_code, vbv_delay;
1369
1370     init_get_bits(&s->gb, buf, buf_size*8);
1371
1372     ref = get_bits(&s->gb, 10); /* temporal ref */
1373     s->pict_type = get_bits(&s->gb, 3);
1374     if (s->pict_type == 0 || s->pict_type > 3)
1375         return -1;
1376
1377     vbv_delay = get_bits(&s->gb, 16);
1378     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) {
1379         s->full_pel[0] = get_bits1(&s->gb);
1380         f_code = get_bits(&s->gb, 3);
1381         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1382             return -1;
1383         f_code += !f_code;
1384         s->mpeg_f_code[0][0] = f_code;
1385         s->mpeg_f_code[0][1] = f_code;
1386     }
1387     if (s->pict_type == AV_PICTURE_TYPE_B) {
1388         s->full_pel[1] = get_bits1(&s->gb);
1389         f_code = get_bits(&s->gb, 3);
1390         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1391             return -1;
1392         f_code += !f_code;
1393         s->mpeg_f_code[1][0] = f_code;
1394         s->mpeg_f_code[1][1] = f_code;
1395     }
1396     s->current_picture.f.pict_type = s->pict_type;
1397     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1398
1399     if (avctx->debug & FF_DEBUG_PICT_INFO)
1400         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1401
1402     s->y_dc_scale = 8;
1403     s->c_dc_scale = 8;
1404     return 0;
1405 }
1406
1407 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1408 {
1409     MpegEncContext *s= &s1->mpeg_enc_ctx;
1410     int horiz_size_ext, vert_size_ext;
1411     int bit_rate_ext;
1412
1413     skip_bits(&s->gb, 1); /* profile and level esc*/
1414     s->avctx->profile       = get_bits(&s->gb, 3);
1415     s->avctx->level         = get_bits(&s->gb, 4);
1416     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1417     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1418     horiz_size_ext          = get_bits(&s->gb, 2);
1419     vert_size_ext           = get_bits(&s->gb, 2);
1420     s->width  |= (horiz_size_ext << 12);
1421     s->height |= (vert_size_ext  << 12);
1422     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1423     s->bit_rate += (bit_rate_ext << 18) * 400;
1424     skip_bits1(&s->gb); /* marker */
1425     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1426
1427     s->low_delay = get_bits1(&s->gb);
1428     if (s->flags & CODEC_FLAG_LOW_DELAY)
1429         s->low_delay = 1;
1430
1431     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1432     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1433
1434     av_dlog(s->avctx, "sequence extension\n");
1435     s->codec_id      = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1436
1437     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1438         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1439                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1440
1441 }
1442
1443 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1444 {
1445     MpegEncContext *s = &s1->mpeg_enc_ctx;
1446     int color_description, w, h;
1447
1448     skip_bits(&s->gb, 3); /* video format */
1449     color_description = get_bits1(&s->gb);
1450     if (color_description) {
1451         s->avctx->color_primaries = get_bits(&s->gb, 8);
1452         s->avctx->color_trc       = get_bits(&s->gb, 8);
1453         s->avctx->colorspace      = get_bits(&s->gb, 8);
1454     }
1455     w = get_bits(&s->gb, 14);
1456     skip_bits(&s->gb, 1); //marker
1457     h = get_bits(&s->gb, 14);
1458     // remaining 3 bits are zero padding
1459
1460     s1->pan_scan.width  = 16 * w;
1461     s1->pan_scan.height = 16 * h;
1462
1463     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1464         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1465 }
1466
1467 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1468 {
1469     MpegEncContext *s = &s1->mpeg_enc_ctx;
1470     int i, nofco;
1471
1472     nofco = 1;
1473     if (s->progressive_sequence) {
1474         if (s->repeat_first_field) {
1475             nofco++;
1476             if (s->top_field_first)
1477                 nofco++;
1478         }
1479     } else {
1480         if (s->picture_structure == PICT_FRAME) {
1481             nofco++;
1482             if (s->repeat_first_field)
1483                 nofco++;
1484         }
1485     }
1486     for (i = 0; i < nofco; i++) {
1487         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1488         skip_bits(&s->gb, 1); // marker
1489         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1490         skip_bits(&s->gb, 1); // marker
1491     }
1492
1493     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1494         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1495                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1496                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1497                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1498 }
1499
1500 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra)
1501 {
1502     int i;
1503
1504     for (i = 0; i < 64; i++) {
1505         int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
1506         int v = get_bits(&s->gb, 8);
1507         if (v == 0) {
1508             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1509             return -1;
1510         }
1511         if (intra && i == 0 && v != 8) {
1512             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1513             v = 8; // needed by pink.mpg / issue1046
1514         }
1515         matrix0[j] = v;
1516         if (matrix1)
1517             matrix1[j] = v;
1518     }
1519     return 0;
1520 }
1521
1522 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1523 {
1524     av_dlog(s->avctx, "matrix extension\n");
1525
1526     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1527     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1528     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
1529     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
1530 }
1531
1532 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1533 {
1534     MpegEncContext *s = &s1->mpeg_enc_ctx;
1535
1536     s->full_pel[0] = s->full_pel[1] = 0;
1537     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1538     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1539     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1540     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1541     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1542         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1543         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1544             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1545                 s->pict_type = AV_PICTURE_TYPE_I;
1546             else
1547                 s->pict_type = AV_PICTURE_TYPE_P;
1548         } else
1549             s->pict_type = AV_PICTURE_TYPE_B;
1550         s->current_picture.f.pict_type = s->pict_type;
1551         s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1552     }
1553     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1554     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1555     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1556     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1557
1558     s->intra_dc_precision         = get_bits(&s->gb, 2);
1559     s->picture_structure          = get_bits(&s->gb, 2);
1560     s->top_field_first            = get_bits1(&s->gb);
1561     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1562     s->concealment_motion_vectors = get_bits1(&s->gb);
1563     s->q_scale_type               = get_bits1(&s->gb);
1564     s->intra_vlc_format           = get_bits1(&s->gb);
1565     s->alternate_scan             = get_bits1(&s->gb);
1566     s->repeat_first_field         = get_bits1(&s->gb);
1567     s->chroma_420_type            = get_bits1(&s->gb);
1568     s->progressive_frame          = get_bits1(&s->gb);
1569
1570
1571     if (s->alternate_scan) {
1572         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1573         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1574     } else {
1575         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1576         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1577     }
1578
1579     /* composite display not parsed */
1580     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1581     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1582     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1583     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1584     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1585     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1586     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1587     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1588     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1589 }
1590
1591 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1592 {
1593     AVCodecContext *avctx = s->avctx;
1594     Mpeg1Context *s1 = (Mpeg1Context*)s;
1595
1596     /* start frame decoding */
1597     if (s->first_field || s->picture_structure == PICT_FRAME) {
1598         if (ff_MPV_frame_start(s, avctx) < 0)
1599             return -1;
1600
1601         ff_er_frame_start(s);
1602
1603         /* first check if we must repeat the frame */
1604         s->current_picture_ptr->f.repeat_pict = 0;
1605         if (s->repeat_first_field) {
1606             if (s->progressive_sequence) {
1607                 if (s->top_field_first)
1608                     s->current_picture_ptr->f.repeat_pict = 4;
1609                 else
1610                     s->current_picture_ptr->f.repeat_pict = 2;
1611             } else if (s->progressive_frame) {
1612                 s->current_picture_ptr->f.repeat_pict = 1;
1613             }
1614         }
1615
1616         *s->current_picture_ptr->f.pan_scan = s1->pan_scan;
1617
1618         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1619             ff_thread_finish_setup(avctx);
1620     } else { // second field
1621         int i;
1622
1623         if (!s->current_picture_ptr) {
1624             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1625             return -1;
1626         }
1627
1628         if (s->avctx->hwaccel &&
1629             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1630             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1631                 av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode first field\n");
1632         }
1633
1634         for (i = 0; i < 4; i++) {
1635             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
1636             if (s->picture_structure == PICT_BOTTOM_FIELD) {
1637                 s->current_picture.f.data[i] += s->current_picture_ptr->f.linesize[i];
1638             }
1639         }
1640     }
1641
1642     if (avctx->hwaccel) {
1643         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1644             return -1;
1645     }
1646
1647 // MPV_frame_start will call this function too,
1648 // but we need to call it on every field
1649     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1650         if (ff_xvmc_field_start(s, avctx) < 0)
1651             return -1;
1652
1653     return 0;
1654 }
1655
1656 #define DECODE_SLICE_ERROR -1
1657 #define DECODE_SLICE_OK     0
1658
1659 /**
1660  * Decode a slice.
1661  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1662  * @return DECODE_SLICE_ERROR if the slice is damaged,
1663  *         DECODE_SLICE_OK if this slice is OK
1664  */
1665 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1666                              const uint8_t **buf, int buf_size)
1667 {
1668     AVCodecContext *avctx = s->avctx;
1669     const int lowres      = s->avctx->lowres;
1670     const int field_pic   = s->picture_structure != PICT_FRAME;
1671
1672     s->resync_mb_x =
1673     s->resync_mb_y = -1;
1674
1675     av_assert0(mb_y < s->mb_height);
1676
1677     init_get_bits(&s->gb, *buf, buf_size * 8);
1678     if(s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1679         skip_bits(&s->gb, 3);
1680
1681     ff_mpeg1_clean_buffers(s);
1682     s->interlaced_dct = 0;
1683
1684     s->qscale = get_qscale(s);
1685
1686     if (s->qscale == 0) {
1687         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1688         return -1;
1689     }
1690
1691     /* extra slice info */
1692     while (get_bits1(&s->gb) != 0) {
1693         skip_bits(&s->gb, 8);
1694     }
1695
1696     s->mb_x = 0;
1697
1698     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1699         skip_bits1(&s->gb);
1700     } else {
1701         while (get_bits_left(&s->gb) > 0) {
1702             int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1703             if (code < 0) {
1704                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1705                 return -1;
1706             }
1707             if (code >= 33) {
1708                 if (code == 33) {
1709                     s->mb_x += 33;
1710                 }
1711                 /* otherwise, stuffing, nothing to do */
1712             } else {
1713                 s->mb_x += code;
1714                 break;
1715             }
1716         }
1717     }
1718
1719     if (s->mb_x >= (unsigned)s->mb_width) {
1720         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1721         return -1;
1722     }
1723
1724     if (avctx->hwaccel) {
1725         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1726         int start_code = -1;
1727         buf_end = avpriv_mpv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1728         if (buf_end < *buf + buf_size)
1729             buf_end -= 4;
1730         s->mb_y = mb_y;
1731         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1732             return DECODE_SLICE_ERROR;
1733         *buf = buf_end;
1734         return DECODE_SLICE_OK;
1735     }
1736
1737     s->resync_mb_x = s->mb_x;
1738     s->resync_mb_y = s->mb_y = mb_y;
1739     s->mb_skip_run = 0;
1740     ff_init_block_index(s);
1741
1742     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1743         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1744              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",
1745                     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],
1746                     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")),
1747                     s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1748                     s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1749                     s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1750         }
1751     }
1752
1753     for (;;) {
1754         // If 1, we memcpy blocks in xvmcvideo.
1755         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1756             ff_xvmc_init_block(s); // set s->block
1757
1758         if (mpeg_decode_mb(s, s->block) < 0)
1759             return -1;
1760
1761         if (s->current_picture.f.motion_val[0] && !s->encoding) { // note motion_val is normally NULL unless we want to extract the MVs
1762             const int wrap = s->b8_stride;
1763             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1764             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1765             int motion_x, motion_y, dir, i;
1766
1767             for (i = 0; i < 2; i++) {
1768                 for (dir = 0; dir < 2; dir++) {
1769                     if (s->mb_intra || (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1770                         motion_x = motion_y = 0;
1771                     } else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1772                         motion_x = s->mv[dir][0][0];
1773                         motion_y = s->mv[dir][0][1];
1774                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1775                         motion_x = s->mv[dir][i][0];
1776                         motion_y = s->mv[dir][i][1];
1777                     }
1778
1779                     s->current_picture.f.motion_val[dir][xy    ][0] = motion_x;
1780                     s->current_picture.f.motion_val[dir][xy    ][1] = motion_y;
1781                     s->current_picture.f.motion_val[dir][xy + 1][0] = motion_x;
1782                     s->current_picture.f.motion_val[dir][xy + 1][1] = motion_y;
1783                     s->current_picture.f.ref_index [dir][b8_xy    ] =
1784                     s->current_picture.f.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1785                     av_assert2(s->field_select[dir][i] == 0 || s->field_select[dir][i] == 1);
1786                 }
1787                 xy += wrap;
1788                 b8_xy +=2;
1789             }
1790         }
1791
1792         s->dest[0] += 16 >> lowres;
1793         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1794         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1795
1796         ff_MPV_decode_mb(s, s->block);
1797
1798         if (++s->mb_x >= s->mb_width) {
1799             const int mb_size = 16 >> s->avctx->lowres;
1800
1801             ff_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
1802             ff_MPV_report_decode_progress(s);
1803
1804             s->mb_x = 0;
1805             s->mb_y += 1 << field_pic;
1806
1807             if (s->mb_y >= s->mb_height) {
1808                 int left   = get_bits_left(&s->gb);
1809                 int is_d10 = s->chroma_format == 2 && s->pict_type == AV_PICTURE_TYPE_I && avctx->profile == 0 && avctx->level == 5
1810                              && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1811                              && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1812
1813                 if (left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1814                     || ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1815                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1816                     return -1;
1817                 } else
1818                     goto eos;
1819             }
1820
1821             ff_init_block_index(s);
1822         }
1823
1824         /* skip mb handling */
1825         if (s->mb_skip_run == -1) {
1826             /* read increment again */
1827             s->mb_skip_run = 0;
1828             for (;;) {
1829                 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1830                 if (code < 0) {
1831                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1832                     return -1;
1833                 }
1834                 if (code >= 33) {
1835                     if (code == 33) {
1836                         s->mb_skip_run += 33;
1837                     } else if (code == 35) {
1838                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1839                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1840                             return -1;
1841                         }
1842                         goto eos; /* end of slice */
1843                     }
1844                     /* otherwise, stuffing, nothing to do */
1845                 } else {
1846                     s->mb_skip_run += code;
1847                     break;
1848                 }
1849             }
1850             if (s->mb_skip_run) {
1851                 int i;
1852                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1853                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1854                     return -1;
1855                 }
1856
1857                 /* skip mb */
1858                 s->mb_intra = 0;
1859                 for (i = 0; i < 12; i++)
1860                     s->block_last_index[i] = -1;
1861                 if (s->picture_structure == PICT_FRAME)
1862                     s->mv_type = MV_TYPE_16X16;
1863                 else
1864                     s->mv_type = MV_TYPE_FIELD;
1865                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1866                     /* if P type, zero motion vector is implied */
1867                     s->mv_dir             = MV_DIR_FORWARD;
1868                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1869                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1870                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1871                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1872                 } else {
1873                     /* if B type, reuse previous vectors and directions */
1874                     s->mv[0][0][0] = s->last_mv[0][0][0];
1875                     s->mv[0][0][1] = s->last_mv[0][0][1];
1876                     s->mv[1][0][0] = s->last_mv[1][0][0];
1877                     s->mv[1][0][1] = s->last_mv[1][0][1];
1878                 }
1879             }
1880         }
1881     }
1882 eos: // end of slice
1883     *buf += (get_bits_count(&s->gb)-1)/8;
1884 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1885     return 0;
1886 }
1887
1888 static int slice_decode_thread(AVCodecContext *c, void *arg)
1889 {
1890     MpegEncContext *s   = *(void**)arg;
1891     const uint8_t *buf  = s->gb.buffer;
1892     int mb_y            = s->start_mb_y;
1893     const int field_pic = s->picture_structure != PICT_FRAME;
1894
1895     s->error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1896
1897     for (;;) {
1898         uint32_t start_code;
1899         int ret;
1900
1901         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1902         emms_c();
1903 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1904 //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);
1905         if (ret < 0) {
1906             if (c->err_recognition & AV_EF_EXPLODE)
1907                 return ret;
1908             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1909                 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);
1910         } else {
1911             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);
1912         }
1913
1914         if (s->mb_y == s->end_mb_y)
1915             return 0;
1916
1917         start_code = -1;
1918         buf = avpriv_mpv_find_start_code(buf, s->gb.buffer_end, &start_code);
1919         mb_y= start_code - SLICE_MIN_START_CODE;
1920         if(s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1921             mb_y += (*buf&0xE0)<<2;
1922         mb_y <<= field_pic;
1923         if (s->picture_structure == PICT_BOTTOM_FIELD)
1924             mb_y++;
1925         if (mb_y < 0 || mb_y >= s->end_mb_y)
1926             return -1;
1927     }
1928 }
1929
1930 /**
1931  * Handle slice ends.
1932  * @return 1 if it seems to be the last slice
1933  */
1934 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1935 {
1936     Mpeg1Context *s1 = avctx->priv_data;
1937     MpegEncContext *s = &s1->mpeg_enc_ctx;
1938
1939     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1940         return 0;
1941
1942     if (s->avctx->hwaccel) {
1943         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1944             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
1945     }
1946
1947     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1948         ff_xvmc_field_end(s);
1949
1950     /* end of slice reached */
1951     if (/*s->mb_y << field_pic == s->mb_height &&*/ !s->first_field && !s->first_slice) {
1952         /* end of image */
1953
1954         s->current_picture_ptr->f.qscale_type = FF_QSCALE_TYPE_MPEG2;
1955
1956         ff_er_frame_end(s);
1957
1958         ff_MPV_frame_end(s);
1959
1960         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
1961             *pict = s->current_picture_ptr->f;
1962             ff_print_debug_info(s, pict);
1963         } else {
1964             if (avctx->active_thread_type & FF_THREAD_FRAME)
1965                 s->picture_number++;
1966             /* latency of 1 frame for I- and P-frames */
1967             /* XXX: use another variable than picture_number */
1968             if (s->last_picture_ptr != NULL) {
1969                 *pict = s->last_picture_ptr->f;
1970                  ff_print_debug_info(s, pict);
1971             }
1972         }
1973
1974         return 1;
1975     } else {
1976         return 0;
1977     }
1978 }
1979
1980 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1981                                  const uint8_t *buf, int buf_size)
1982 {
1983     Mpeg1Context *s1 = avctx->priv_data;
1984     MpegEncContext *s = &s1->mpeg_enc_ctx;
1985     int width, height;
1986     int i, v, j;
1987
1988     init_get_bits(&s->gb, buf, buf_size*8);
1989
1990     width  = get_bits(&s->gb, 12);
1991     height = get_bits(&s->gb, 12);
1992     if (width <= 0 || height <= 0)
1993         return -1;
1994     s->aspect_ratio_info = get_bits(&s->gb, 4);
1995     if (s->aspect_ratio_info == 0) {
1996         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1997         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
1998             return -1;
1999     }
2000     s->frame_rate_index = get_bits(&s->gb, 4);
2001     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
2002         return -1;
2003     s->bit_rate = get_bits(&s->gb, 18) * 400;
2004     if (get_bits1(&s->gb) == 0) /* marker */
2005         return -1;
2006     s->width  = width;
2007     s->height = height;
2008
2009     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2010     skip_bits(&s->gb, 1);
2011
2012     /* get matrix */
2013     if (get_bits1(&s->gb)) {
2014         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2015     } else {
2016         for (i = 0; i < 64; i++) {
2017             j = s->dsp.idct_permutation[i];
2018             v = ff_mpeg1_default_intra_matrix[i];
2019             s->intra_matrix[j]        = v;
2020             s->chroma_intra_matrix[j] = v;
2021         }
2022     }
2023     if (get_bits1(&s->gb)) {
2024         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2025     } else {
2026         for (i = 0; i < 64; i++) {
2027             int j = s->dsp.idct_permutation[i];
2028             v = ff_mpeg1_default_non_intra_matrix[i];
2029             s->inter_matrix[j]        = v;
2030             s->chroma_inter_matrix[j] = v;
2031         }
2032     }
2033
2034     if (show_bits(&s->gb, 23) != 0) {
2035         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2036         return -1;
2037     }
2038
2039     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
2040     s->progressive_sequence = 1;
2041     s->progressive_frame    = 1;
2042     s->picture_structure    = PICT_FRAME;
2043     s->first_field          = 0;
2044     s->frame_pred_frame_dct = 1;
2045     s->chroma_format        = 1;
2046     s->codec_id             = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2047     s->out_format           = FMT_MPEG1;
2048     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2049     if (s->flags & CODEC_FLAG_LOW_DELAY)
2050         s->low_delay = 1;
2051
2052     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2053         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2054                s->avctx->rc_buffer_size, s->bit_rate);
2055
2056     return 0;
2057 }
2058
2059 static int vcr2_init_sequence(AVCodecContext *avctx)
2060 {
2061     Mpeg1Context *s1 = avctx->priv_data;
2062     MpegEncContext *s = &s1->mpeg_enc_ctx;
2063     int i, v;
2064
2065     /* start new MPEG-1 context decoding */
2066     s->out_format = FMT_MPEG1;
2067     if (s1->mpeg_enc_ctx_allocated) {
2068         ff_MPV_common_end(s);
2069     }
2070     s->width  = avctx->coded_width;
2071     s->height = avctx->coded_height;
2072     avctx->has_b_frames = 0; // true?
2073     s->low_delay = 1;
2074
2075     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2076     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
2077
2078     if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel )
2079         if (avctx->idct_algo == FF_IDCT_AUTO)
2080             avctx->idct_algo = FF_IDCT_SIMPLE;
2081
2082     if (ff_MPV_common_init(s) < 0)
2083         return -1;
2084     s1->mpeg_enc_ctx_allocated = 1;
2085
2086     for (i = 0; i < 64; i++) {
2087         int j = s->dsp.idct_permutation[i];
2088         v = ff_mpeg1_default_intra_matrix[i];
2089         s->intra_matrix[j]        = v;
2090         s->chroma_intra_matrix[j] = v;
2091
2092         v = ff_mpeg1_default_non_intra_matrix[i];
2093         s->inter_matrix[j]        = v;
2094         s->chroma_inter_matrix[j] = v;
2095     }
2096
2097     s->progressive_sequence  = 1;
2098     s->progressive_frame     = 1;
2099     s->picture_structure     = PICT_FRAME;
2100     s->first_field           = 0;
2101     s->frame_pred_frame_dct  = 1;
2102     s->chroma_format         = 1;
2103     if (s->codec_tag == AV_RL32("BW10")) {
2104         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2105     } else {
2106         exchange_uv(s); // common init reset pblocks, so we swap them here
2107         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2108         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2109     }
2110     s1->save_width           = s->width;
2111     s1->save_height          = s->height;
2112     s1->save_progressive_seq = s->progressive_sequence;
2113     return 0;
2114 }
2115
2116
2117 static void mpeg_decode_user_data(AVCodecContext *avctx,
2118                                   const uint8_t *p, int buf_size)
2119 {
2120     Mpeg1Context *s = avctx->priv_data;
2121     const uint8_t *buf_end = p + buf_size;
2122
2123     if(buf_size > 29){
2124         int i;
2125         for(i=0; i<20; i++)
2126             if(!memcmp(p+i, "\0TMPGEXS\0", 9)){
2127                 s->tmpgexs= 1;
2128             }
2129
2130 /*        for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2131             av_log(0,0, "%c", p[i]);
2132         }
2133             av_log(0,0, "\n");*/
2134     }
2135
2136     /* we parse the DTG active format information */
2137     if (buf_end - p >= 5 &&
2138         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2139         int flags = p[4];
2140         p += 5;
2141         if (flags & 0x80) {
2142             /* skip event id */
2143             p += 2;
2144         }
2145         if (flags & 0x40) {
2146             if (buf_end - p < 1)
2147                 return;
2148             avctx->dtg_active_format = p[0] & 0x0f;
2149         }
2150     }
2151 }
2152
2153 static void mpeg_decode_gop(AVCodecContext *avctx,
2154                             const uint8_t *buf, int buf_size)
2155 {
2156     Mpeg1Context *s1  = avctx->priv_data;
2157     MpegEncContext *s = &s1->mpeg_enc_ctx;
2158     int broken_link;
2159     int64_t tc;
2160
2161     init_get_bits(&s->gb, buf, buf_size*8);
2162
2163     tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2164
2165     s->closed_gop = get_bits1(&s->gb);
2166     /*broken_link indicate that after editing the
2167       reference frames of the first B-Frames after GOP I-Frame
2168       are missing (open gop)*/
2169     broken_link = get_bits1(&s->gb);
2170
2171     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2172         char tcbuf[AV_TIMECODE_STR_SIZE];
2173         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2174         av_log(s->avctx, AV_LOG_DEBUG,
2175                "GOP (%s) closed_gop=%d broken_link=%d\n",
2176                tcbuf, s->closed_gop, broken_link);
2177     }
2178 }
2179 /**
2180  * Find the end of the current frame in the bitstream.
2181  * @return the position of the first byte of the next frame, or -1
2182  */
2183 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
2184 {
2185     int i;
2186     uint32_t state = pc->state;
2187
2188     /* EOF considered as end of frame */
2189     if (buf_size == 0)
2190         return 0;
2191
2192 /*
2193  0  frame start         -> 1/4
2194  1  first_SEQEXT        -> 0/2
2195  2  first field start   -> 3/0
2196  3  second_SEQEXT       -> 2/0
2197  4  searching end
2198 */
2199
2200     for (i = 0; i < buf_size; i++) {
2201         av_assert1(pc->frame_start_found >= 0 && pc->frame_start_found <= 4);
2202         if (pc->frame_start_found & 1) {
2203             if (state == EXT_START_CODE && (buf[i] & 0xF0) != 0x80)
2204                 pc->frame_start_found--;
2205             else if (state == EXT_START_CODE + 2) {
2206                 if ((buf[i] & 3) == 3)
2207                     pc->frame_start_found = 0;
2208                 else
2209                     pc->frame_start_found = (pc->frame_start_found + 1) & 3;
2210             }
2211             state++;
2212         } else {
2213             i = avpriv_mpv_find_start_code(buf + i, buf + buf_size, &state) - buf - 1;
2214             if (pc->frame_start_found == 0 && state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE) {
2215                 i++;
2216                 pc->frame_start_found = 4;
2217             }
2218             if (state == SEQ_END_CODE) {
2219                 pc->frame_start_found = 0;
2220                 pc->state=-1;
2221                 return i+1;
2222             }
2223             if (pc->frame_start_found == 2 && state == SEQ_START_CODE)
2224                 pc->frame_start_found = 0;
2225             if (pc->frame_start_found  < 4 && state == EXT_START_CODE)
2226                 pc->frame_start_found++;
2227             if (pc->frame_start_found == 4 && (state & 0xFFFFFF00) == 0x100) {
2228                 if (state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE) {
2229                     pc->frame_start_found = 0;
2230                     pc->state             = -1;
2231                     return i - 3;
2232                 }
2233             }
2234             if (pc->frame_start_found == 0 && s && state == PICTURE_START_CODE) {
2235                 ff_fetch_timestamp(s, i - 3, 1);
2236             }
2237         }
2238     }
2239     pc->state = state;
2240     return END_NOT_FOUND;
2241 }
2242
2243 static int decode_chunks(AVCodecContext *avctx,
2244                          AVFrame *picture, int *data_size,
2245                          const uint8_t *buf, int buf_size)
2246 {
2247     Mpeg1Context *s = avctx->priv_data;
2248     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2249     const uint8_t *buf_ptr = buf;
2250     const uint8_t *buf_end = buf + buf_size;
2251     int ret, input_size;
2252     int last_code = 0;
2253
2254     for (;;) {
2255         /* find next start code */
2256         uint32_t start_code = -1;
2257         buf_ptr = avpriv_mpv_find_start_code(buf_ptr, buf_end, &start_code);
2258         if (start_code > 0x1ff) {
2259             if (s2->pict_type != AV_PICTURE_TYPE_B || avctx->skip_frame <= AVDISCARD_DEFAULT) {
2260                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2261                     int i;
2262                     av_assert0(avctx->thread_count > 1);
2263
2264                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
2265                     for (i = 0; i < s->slice_count; i++)
2266                         s2->error_count += s2->thread_context[i]->error_count;
2267                 }
2268
2269                 if (CONFIG_VDPAU && uses_vdpau(avctx))
2270                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2271
2272
2273                 if (slice_end(avctx, picture)) {
2274                     if (s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2275                         *data_size = sizeof(AVPicture);
2276                 }
2277             }
2278             s2->pict_type = 0;
2279             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2280         }
2281
2282         input_size = buf_end - buf_ptr;
2283
2284         if (avctx->debug & FF_DEBUG_STARTCODE) {
2285             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2286         }
2287
2288         /* prepare data for next start code */
2289         switch (start_code) {
2290         case SEQ_START_CODE:
2291             if (last_code == 0) {
2292                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2293                 if(buf != avctx->extradata)
2294                     s->sync=1;
2295             } else {
2296                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
2297                 if (avctx->err_recognition & AV_EF_EXPLODE)
2298                     return AVERROR_INVALIDDATA;
2299             }
2300             break;
2301
2302         case PICTURE_START_CODE:
2303             if(s->tmpgexs){
2304                 s2->intra_dc_precision= 3;
2305                 s2->intra_matrix[0]= 1;
2306             }
2307             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && s->slice_count) {
2308                 int i;
2309
2310                 avctx->execute(avctx, slice_decode_thread,
2311                                s2->thread_context, NULL,
2312                                s->slice_count, sizeof(void*));
2313                 for (i = 0; i < s->slice_count; i++)
2314                     s2->error_count += s2->thread_context[i]->error_count;
2315                 s->slice_count = 0;
2316             }
2317             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2318                 ret = mpeg_decode_postinit(avctx);
2319                 if (ret < 0) {
2320                     av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
2321                     return ret;
2322                 }
2323
2324                 /* we have a complete image: we try to decompress it */
2325                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2326                     s2->pict_type = 0;
2327                 s2->first_slice = 1;
2328                 last_code = PICTURE_START_CODE;
2329             } else {
2330                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
2331                 if (avctx->err_recognition & AV_EF_EXPLODE)
2332                     return AVERROR_INVALIDDATA;
2333             }
2334             break;
2335         case EXT_START_CODE:
2336             init_get_bits(&s2->gb, buf_ptr, input_size*8);
2337
2338             switch (get_bits(&s2->gb, 4)) {
2339             case 0x1:
2340                 if (last_code == 0) {
2341                 mpeg_decode_sequence_extension(s);
2342                 } else {
2343                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
2344                     if (avctx->err_recognition & AV_EF_EXPLODE)
2345                         return AVERROR_INVALIDDATA;
2346                 }
2347                 break;
2348             case 0x2:
2349                 mpeg_decode_sequence_display_extension(s);
2350                 break;
2351             case 0x3:
2352                 mpeg_decode_quant_matrix_extension(s2);
2353                 break;
2354             case 0x7:
2355                 mpeg_decode_picture_display_extension(s);
2356                 break;
2357             case 0x8:
2358                 if (last_code == PICTURE_START_CODE) {
2359                     mpeg_decode_picture_coding_extension(s);
2360                 } else {
2361                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
2362                     if (avctx->err_recognition & AV_EF_EXPLODE)
2363                         return AVERROR_INVALIDDATA;
2364                 }
2365                 break;
2366             }
2367             break;
2368         case USER_START_CODE:
2369             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2370             break;
2371         case GOP_START_CODE:
2372             if (last_code == 0) {
2373                 s2->first_field=0;
2374                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2375                 s->sync=1;
2376             } else {
2377                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
2378                 if (avctx->err_recognition & AV_EF_EXPLODE)
2379                     return AVERROR_INVALIDDATA;
2380             }
2381             break;
2382         default:
2383             if (start_code >= SLICE_MIN_START_CODE &&
2384                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2385
2386                 if (s2->progressive_sequence && !s2->progressive_frame) {
2387                     s2->progressive_frame = 1;
2388                     av_log(s2->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
2389                 }
2390
2391                 if (s2->picture_structure == 0 || (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2392                     av_log(s2->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s2->picture_structure);
2393                     s2->picture_structure = PICT_FRAME;
2394                 }
2395
2396                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct) {
2397                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2398                 }
2399
2400                 if (s2->picture_structure == PICT_FRAME) {
2401                     s2->first_field = 0;
2402                     s2->v_edge_pos  = 16 * s2->mb_height;
2403                 } else {
2404                     s2->first_field ^= 1;
2405                     s2->v_edge_pos   = 8 * s2->mb_height;
2406                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2407                 }
2408             }
2409             if (start_code >= SLICE_MIN_START_CODE &&
2410                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2411                 const int field_pic = s2->picture_structure != PICT_FRAME;
2412                 int mb_y = start_code - SLICE_MIN_START_CODE;
2413                 last_code = SLICE_MIN_START_CODE;
2414                 if(s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2415                     mb_y += (*buf_ptr&0xE0)<<2;
2416
2417                 mb_y <<= field_pic;
2418                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2419                     mb_y++;
2420
2421                 if (mb_y >= s2->mb_height) {
2422                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2423                     return -1;
2424                 }
2425
2426                 if (s2->last_picture_ptr == NULL) {
2427                 /* Skip B-frames if we do not have reference frames and gop is not closed */
2428                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2429                         if (!s2->closed_gop)
2430                             break;
2431                     }
2432                 }
2433                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->flags2 & CODEC_FLAG2_SHOW_ALL))
2434                     s->sync=1;
2435                 if (s2->next_picture_ptr == NULL) {
2436                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2437                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) break;
2438                 }
2439                 if ((avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type == AV_PICTURE_TYPE_B) ||
2440                     (avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type != AV_PICTURE_TYPE_I) ||
2441                      avctx->skip_frame >= AVDISCARD_ALL)
2442                     break;
2443
2444                 if (!s->mpeg_enc_ctx_allocated)
2445                     break;
2446
2447                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2448                     if (mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2449                         break;
2450                 }
2451
2452                 if (!s2->pict_type) {
2453                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2454                     if (avctx->err_recognition & AV_EF_EXPLODE)
2455                         return AVERROR_INVALIDDATA;
2456                     break;
2457                 }
2458
2459                 if (s2->first_slice) {
2460                     s2->first_slice = 0;
2461                     if (mpeg_field_start(s2, buf, buf_size) < 0)
2462                         return -1;
2463                 }
2464                 if (!s2->current_picture_ptr) {
2465                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2466                     return AVERROR_INVALIDDATA;
2467                 }
2468
2469                 if (uses_vdpau(avctx)) {
2470                     s->slice_count++;
2471                     break;
2472                 }
2473
2474                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2475                     int threshold = (s2->mb_height * s->slice_count +
2476                                      s2->slice_context_count / 2) /
2477                                     s2->slice_context_count;
2478                     av_assert0(avctx->thread_count > 1);
2479                     if (threshold <= mb_y) {
2480                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2481
2482                         thread_context->start_mb_y = mb_y;
2483                         thread_context->end_mb_y   = s2->mb_height;
2484                         if (s->slice_count) {
2485                             s2->thread_context[s->slice_count-1]->end_mb_y = mb_y;
2486                             ff_update_duplicate_context(thread_context, s2);
2487                         }
2488                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2489                         s->slice_count++;
2490                     }
2491                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2492                 } else {
2493                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2494                     emms_c();
2495
2496                     if (ret < 0) {
2497                         if (avctx->err_recognition & AV_EF_EXPLODE)
2498                             return ret;
2499                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2500                             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);
2501                     } else {
2502                         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);
2503                     }
2504                 }
2505             }
2506             break;
2507         }
2508     }
2509 }
2510
2511 static int mpeg_decode_frame(AVCodecContext *avctx,
2512                              void *data, int *data_size,
2513                              AVPacket *avpkt)
2514 {
2515     const uint8_t *buf = avpkt->data;
2516     int buf_size = avpkt->size;
2517     Mpeg1Context *s = avctx->priv_data;
2518     AVFrame *picture = data;
2519     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2520     av_dlog(avctx, "fill_buffer\n");
2521
2522     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2523         /* special case for last picture */
2524         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2525             *picture = s2->next_picture_ptr->f;
2526             s2->next_picture_ptr = NULL;
2527
2528             *data_size = sizeof(AVFrame);
2529         }
2530         return buf_size;
2531     }
2532
2533     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2534         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
2535
2536         if (ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0)
2537             return buf_size;
2538     }
2539
2540     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2541     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2542                                            || s2->codec_tag == AV_RL32("BW10")
2543                                           ))
2544         vcr2_init_sequence(avctx);
2545
2546     s->slice_count = 0;
2547
2548     if (avctx->extradata && !s->parsed_extra) {
2549         int ret = decode_chunks(avctx, picture, data_size, avctx->extradata, avctx->extradata_size);
2550         if(*data_size) {
2551             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2552             *data_size = 0;
2553         }
2554         s->parsed_extra = 1;
2555         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2556             return ret;
2557     }
2558
2559     return decode_chunks(avctx, picture, data_size, buf, buf_size);
2560 }
2561
2562
2563 static void flush(AVCodecContext *avctx)
2564 {
2565     Mpeg1Context *s = avctx->priv_data;
2566
2567     s->sync=0;
2568
2569     ff_mpeg_flush(avctx);
2570 }
2571
2572 static int mpeg_decode_end(AVCodecContext *avctx)
2573 {
2574     Mpeg1Context *s = avctx->priv_data;
2575
2576     if (s->mpeg_enc_ctx_allocated)
2577         ff_MPV_common_end(&s->mpeg_enc_ctx);
2578     return 0;
2579 }
2580
2581 static const AVProfile mpeg2_video_profiles[] = {
2582     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2583     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2584     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2585     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2586     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2587     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2588     { FF_PROFILE_RESERVED,           "Reserved"           },
2589     { FF_PROFILE_RESERVED,           "Reserved"           },
2590     { FF_PROFILE_UNKNOWN },
2591 };
2592
2593
2594 AVCodec ff_mpeg1video_decoder = {
2595     .name                  = "mpeg1video",
2596     .type                  = AVMEDIA_TYPE_VIDEO,
2597     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2598     .priv_data_size        = sizeof(Mpeg1Context),
2599     .init                  = mpeg_decode_init,
2600     .close                 = mpeg_decode_end,
2601     .decode                = mpeg_decode_frame,
2602     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2603                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2604                              CODEC_CAP_SLICE_THREADS,
2605     .flush                 = flush,
2606     .max_lowres            = 3,
2607     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2608     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2609 };
2610
2611 AVCodec ff_mpeg2video_decoder = {
2612     .name           = "mpeg2video",
2613     .type           = AVMEDIA_TYPE_VIDEO,
2614     .id             = AV_CODEC_ID_MPEG2VIDEO,
2615     .priv_data_size = sizeof(Mpeg1Context),
2616     .init           = mpeg_decode_init,
2617     .close          = mpeg_decode_end,
2618     .decode         = mpeg_decode_frame,
2619     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2620                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2621                       CODEC_CAP_SLICE_THREADS,
2622     .flush          = flush,
2623     .max_lowres     = 3,
2624     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2625     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2626 };
2627
2628 //legacy decoder
2629 AVCodec ff_mpegvideo_decoder = {
2630     .name           = "mpegvideo",
2631     .type           = AVMEDIA_TYPE_VIDEO,
2632     .id             = AV_CODEC_ID_MPEG2VIDEO,
2633     .priv_data_size = sizeof(Mpeg1Context),
2634     .init           = mpeg_decode_init,
2635     .close          = mpeg_decode_end,
2636     .decode         = mpeg_decode_frame,
2637     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
2638     .flush          = flush,
2639     .max_lowres     = 3,
2640     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2641 };
2642
2643 #if CONFIG_MPEG_XVMC_DECODER
2644 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2645 {
2646     if (avctx->active_thread_type & FF_THREAD_SLICE)
2647         return -1;
2648     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2649         return -1;
2650     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2651         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2652     }
2653     mpeg_decode_init(avctx);
2654
2655     avctx->pix_fmt           = PIX_FMT_XVMC_MPEG2_IDCT;
2656     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2657
2658     return 0;
2659 }
2660
2661 AVCodec ff_mpeg_xvmc_decoder = {
2662     .name           = "mpegvideo_xvmc",
2663     .type           = AVMEDIA_TYPE_VIDEO,
2664     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2665     .priv_data_size = sizeof(Mpeg1Context),
2666     .init           = mpeg_mc_decode_init,
2667     .close          = mpeg_decode_end,
2668     .decode         = mpeg_decode_frame,
2669     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2670                       CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2671     .flush          = flush,
2672     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2673 };
2674
2675 #endif
2676
2677 #if CONFIG_MPEG_VDPAU_DECODER
2678 AVCodec ff_mpeg_vdpau_decoder = {
2679     .name           = "mpegvideo_vdpau",
2680     .type           = AVMEDIA_TYPE_VIDEO,
2681     .id             = AV_CODEC_ID_MPEG2VIDEO,
2682     .priv_data_size = sizeof(Mpeg1Context),
2683     .init           = mpeg_decode_init,
2684     .close          = mpeg_decode_end,
2685     .decode         = mpeg_decode_frame,
2686     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2687                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2688     .flush          = flush,
2689     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2690 };
2691 #endif
2692
2693 #if CONFIG_MPEG1_VDPAU_DECODER
2694 AVCodec ff_mpeg1_vdpau_decoder = {
2695     .name           = "mpeg1video_vdpau",
2696     .type           = AVMEDIA_TYPE_VIDEO,
2697     .id             = AV_CODEC_ID_MPEG1VIDEO,
2698     .priv_data_size = sizeof(Mpeg1Context),
2699     .init           = mpeg_decode_init,
2700     .close          = mpeg_decode_end,
2701     .decode         = mpeg_decode_frame,
2702     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2703                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2704     .flush          = flush,
2705     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2706 };
2707 #endif