1bf51f085efb9261e75bbabc8705b31a215de44d
[ffmpeg.git] / libavcodec / mpeg12dec.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 Libav.
7  *
8  * Libav 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  * Libav 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 Libav; 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 #include <inttypes.h>
29
30 #include "libavutil/attributes.h"
31 #include "libavutil/internal.h"
32 #include "libavutil/stereo3d.h"
33
34 #include "avcodec.h"
35 #include "bytestream.h"
36 #include "error_resilience.h"
37 #include "idctdsp.h"
38 #include "internal.h"
39 #include "mpeg_er.h"
40 #include "mpeg12.h"
41 #include "mpeg12data.h"
42 #include "mpegutils.h"
43 #include "mpegvideo.h"
44 #include "thread.h"
45 #include "version.h"
46 #include "xvmc_internal.h"
47
48 typedef struct Mpeg1Context {
49     MpegEncContext mpeg_enc_ctx;
50     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
51     int repeat_field;           /* true if we must repeat the field */
52     AVPanScan pan_scan;         /* some temporary storage for the panscan */
53     AVStereo3D stereo3d;
54     int has_stereo3d;
55     uint8_t *a53_caption;
56     int a53_caption_size;
57     uint8_t afd;
58     int has_afd;
59     int slice_count;
60     int save_aspect_info;
61     int save_width, save_height, save_progressive_seq;
62     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
63     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
64     int closed_gop;             /* GOP is closed */
65     int first_slice;
66     int extradata_decoded;
67 } Mpeg1Context;
68
69 #define MB_TYPE_ZERO_MV   0x20000000
70
71 static const uint32_t ptype2mb_type[7] = {
72                     MB_TYPE_INTRA,
73                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
74                     MB_TYPE_L0,
75                     MB_TYPE_L0 | MB_TYPE_CBP,
76     MB_TYPE_QUANT | MB_TYPE_INTRA,
77     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
78     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
79 };
80
81 static const uint32_t btype2mb_type[11] = {
82                     MB_TYPE_INTRA,
83                     MB_TYPE_L1,
84                     MB_TYPE_L1   | MB_TYPE_CBP,
85                     MB_TYPE_L0,
86                     MB_TYPE_L0   | MB_TYPE_CBP,
87                     MB_TYPE_L0L1,
88                     MB_TYPE_L0L1 | MB_TYPE_CBP,
89     MB_TYPE_QUANT | MB_TYPE_INTRA,
90     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
91     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
92     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
93 };
94
95 static const uint8_t non_linear_qscale[32] = {
96      0,  1,  2,  3,  4,  5,   6,   7,
97      8, 10, 12, 14, 16, 18,  20,  22,
98     24, 28, 32, 36, 40, 44,  48,  52,
99     56, 64, 72, 80, 88, 96, 104, 112,
100 };
101
102 /* as H.263, but only 17 codes */
103 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
104 {
105     int code, sign, val, shift;
106
107     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
108     if (code == 0)
109         return pred;
110     if (code < 0)
111         return 0xffff;
112
113     sign  = get_bits1(&s->gb);
114     shift = fcode - 1;
115     val   = code;
116     if (shift) {
117         val  = (val - 1) << shift;
118         val |= get_bits(&s->gb, shift);
119         val++;
120     }
121     if (sign)
122         val = -val;
123     val += pred;
124
125     /* modulo decoding */
126     return sign_extend(val, 5 + shift);
127 }
128
129 #define check_scantable_index(ctx, x)                                         \
130     do {                                                                      \
131         if ((x) > 63) {                                                       \
132             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
133                    ctx->mb_x, ctx->mb_y);                                     \
134             return AVERROR_INVALIDDATA;                                       \
135         }                                                                     \
136     } while (0)
137
138 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
139                                            int16_t *block, int n)
140 {
141     int level, dc, diff, i, j, run;
142     int component;
143     RLTable *rl                  = &ff_rl_mpeg1;
144     uint8_t *const scantable     = s->intra_scantable.permutated;
145     const uint16_t *quant_matrix = s->intra_matrix;
146     const int qscale             = s->qscale;
147
148     /* DC coefficient */
149     component = (n <= 3 ? 0 : n - 4 + 1);
150     diff = decode_dc(&s->gb, component);
151     if (diff >= 0xffff)
152         return AVERROR_INVALIDDATA;
153     dc  = s->last_dc[component];
154     dc += diff;
155     s->last_dc[component] = dc;
156     block[0] = dc * quant_matrix[0];
157     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
158     i = 0;
159     {
160         OPEN_READER(re, &s->gb);
161         /* now quantify & encode AC coefficients */
162         for (;;) {
163             UPDATE_CACHE(re, &s->gb);
164             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
165                        TEX_VLC_BITS, 2, 0);
166
167             if (level == 127) {
168                 break;
169             } else if (level != 0) {
170                 i += run;
171                 check_scantable_index(s, i);
172                 j = scantable[i];
173                 level = (level * qscale * quant_matrix[j]) >> 4;
174                 level = (level - 1) | 1;
175                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
176                         SHOW_SBITS(re, &s->gb, 1);
177                 LAST_SKIP_BITS(re, &s->gb, 1);
178             } else {
179                 /* escape */
180                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
181                 LAST_SKIP_BITS(re, &s->gb, 6);
182                 UPDATE_CACHE(re, &s->gb);
183                 level = SHOW_SBITS(re, &s->gb, 8);
184                 SKIP_BITS(re, &s->gb, 8);
185                 if (level == -128) {
186                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
187                     LAST_SKIP_BITS(re, &s->gb, 8);
188                 } else if (level == 0) {
189                     level = SHOW_UBITS(re, &s->gb, 8);
190                     LAST_SKIP_BITS(re, &s->gb, 8);
191                 }
192                 i += run;
193                 check_scantable_index(s, i);
194                 j = scantable[i];
195                 if (level < 0) {
196                     level = -level;
197                     level = (level * qscale * quant_matrix[j]) >> 4;
198                     level = (level - 1) | 1;
199                     level = -level;
200                 } else {
201                     level = (level * qscale * quant_matrix[j]) >> 4;
202                     level = (level - 1) | 1;
203                 }
204             }
205
206             block[j] = level;
207         }
208         CLOSE_READER(re, &s->gb);
209     }
210     s->block_last_index[n] = i;
211     return 0;
212 }
213
214 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
215 {
216     return mpeg1_decode_block_intra(s, block, n);
217 }
218
219 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
220                                            int16_t *block, int n)
221 {
222     int level, i, j, run;
223     RLTable *rl                  = &ff_rl_mpeg1;
224     uint8_t *const scantable     = s->intra_scantable.permutated;
225     const uint16_t *quant_matrix = s->inter_matrix;
226     const int qscale             = s->qscale;
227
228     {
229         OPEN_READER(re, &s->gb);
230         i = -1;
231         // special case for first coefficient, no need to add second VLC table
232         UPDATE_CACHE(re, &s->gb);
233         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
234             level = (3 * qscale * quant_matrix[0]) >> 5;
235             level = (level - 1) | 1;
236             if (GET_CACHE(re, &s->gb) & 0x40000000)
237                 level = -level;
238             block[0] = level;
239             i++;
240             SKIP_BITS(re, &s->gb, 2);
241             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
242                 goto end;
243         }
244         /* now quantify & encode AC coefficients */
245         for (;;) {
246             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
247                        TEX_VLC_BITS, 2, 0);
248
249             if (level != 0) {
250                 i += run;
251                 check_scantable_index(s, i);
252                 j = scantable[i];
253                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
254                 level = (level - 1) | 1;
255                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
256                         SHOW_SBITS(re, &s->gb, 1);
257                 SKIP_BITS(re, &s->gb, 1);
258             } else {
259                 /* escape */
260                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
261                 LAST_SKIP_BITS(re, &s->gb, 6);
262                 UPDATE_CACHE(re, &s->gb);
263                 level = SHOW_SBITS(re, &s->gb, 8);
264                 SKIP_BITS(re, &s->gb, 8);
265                 if (level == -128) {
266                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
267                     SKIP_BITS(re, &s->gb, 8);
268                 } else if (level == 0) {
269                     level = SHOW_UBITS(re, &s->gb, 8);
270                     SKIP_BITS(re, &s->gb, 8);
271                 }
272                 i += run;
273                 check_scantable_index(s, i);
274                 j = scantable[i];
275                 if (level < 0) {
276                     level = -level;
277                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
278                     level = (level - 1) | 1;
279                     level = -level;
280                 } else {
281                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
282                     level = (level - 1) | 1;
283                 }
284             }
285
286             block[j] = level;
287             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
288                 break;
289             UPDATE_CACHE(re, &s->gb);
290         }
291 end:
292         LAST_SKIP_BITS(re, &s->gb, 2);
293         CLOSE_READER(re, &s->gb);
294     }
295     s->block_last_index[n] = i;
296     return 0;
297 }
298
299 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
300                                                 int16_t *block, int n)
301 {
302     int level, i, j, run;
303     RLTable *rl              = &ff_rl_mpeg1;
304     uint8_t *const scantable = s->intra_scantable.permutated;
305     const int qscale         = s->qscale;
306
307     {
308         OPEN_READER(re, &s->gb);
309         i = -1;
310         // Special case for first coefficient, no need to add second VLC table.
311         UPDATE_CACHE(re, &s->gb);
312         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
313             level = (3 * qscale) >> 1;
314             level = (level - 1) | 1;
315             if (GET_CACHE(re, &s->gb) & 0x40000000)
316                 level = -level;
317             block[0] = level;
318             i++;
319             SKIP_BITS(re, &s->gb, 2);
320             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
321                 goto end;
322         }
323
324         /* now quantify & encode AC coefficients */
325         for (;;) {
326             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
327                        TEX_VLC_BITS, 2, 0);
328
329             if (level != 0) {
330                 i += run;
331                 check_scantable_index(s, i);
332                 j = scantable[i];
333                 level = ((level * 2 + 1) * qscale) >> 1;
334                 level = (level - 1) | 1;
335                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
336                         SHOW_SBITS(re, &s->gb, 1);
337                 SKIP_BITS(re, &s->gb, 1);
338             } else {
339                 /* escape */
340                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
341                 LAST_SKIP_BITS(re, &s->gb, 6);
342                 UPDATE_CACHE(re, &s->gb);
343                 level = SHOW_SBITS(re, &s->gb, 8);
344                 SKIP_BITS(re, &s->gb, 8);
345                 if (level == -128) {
346                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
347                     SKIP_BITS(re, &s->gb, 8);
348                 } else if (level == 0) {
349                     level = SHOW_UBITS(re, &s->gb, 8);
350                     SKIP_BITS(re, &s->gb, 8);
351                 }
352                 i += run;
353                 check_scantable_index(s, i);
354                 j = scantable[i];
355                 if (level < 0) {
356                     level = -level;
357                     level = ((level * 2 + 1) * qscale) >> 1;
358                     level = (level - 1) | 1;
359                     level = -level;
360                 } else {
361                     level = ((level * 2 + 1) * qscale) >> 1;
362                     level = (level - 1) | 1;
363                 }
364             }
365
366             block[j] = level;
367             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
368                 break;
369             UPDATE_CACHE(re, &s->gb);
370         }
371 end:
372         LAST_SKIP_BITS(re, &s->gb, 2);
373         CLOSE_READER(re, &s->gb);
374     }
375     s->block_last_index[n] = i;
376     return 0;
377 }
378
379 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
380                                                int16_t *block, int n)
381 {
382     int level, i, j, run;
383     RLTable *rl = &ff_rl_mpeg1;
384     uint8_t *const scantable = s->intra_scantable.permutated;
385     const uint16_t *quant_matrix;
386     const int qscale = s->qscale;
387     int mismatch;
388
389     mismatch = 1;
390
391     {
392         OPEN_READER(re, &s->gb);
393         i = -1;
394         if (n < 4)
395             quant_matrix = s->inter_matrix;
396         else
397             quant_matrix = s->chroma_inter_matrix;
398
399         // Special case for first coefficient, no need to add second VLC table.
400         UPDATE_CACHE(re, &s->gb);
401         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
402             level = (3 * qscale * quant_matrix[0]) >> 5;
403             if (GET_CACHE(re, &s->gb) & 0x40000000)
404                 level = -level;
405             block[0]  = level;
406             mismatch ^= level;
407             i++;
408             SKIP_BITS(re, &s->gb, 2);
409             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
410                 goto end;
411         }
412
413         /* now quantify & encode AC coefficients */
414         for (;;) {
415             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
416                        TEX_VLC_BITS, 2, 0);
417
418             if (level != 0) {
419                 i += run;
420                 check_scantable_index(s, i);
421                 j = scantable[i];
422                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
423                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
424                         SHOW_SBITS(re, &s->gb, 1);
425                 SKIP_BITS(re, &s->gb, 1);
426             } else {
427                 /* escape */
428                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
429                 LAST_SKIP_BITS(re, &s->gb, 6);
430                 UPDATE_CACHE(re, &s->gb);
431                 level = SHOW_SBITS(re, &s->gb, 12);
432                 SKIP_BITS(re, &s->gb, 12);
433
434                 i += run;
435                 check_scantable_index(s, i);
436                 j = scantable[i];
437                 if (level < 0) {
438                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
439                     level = -level;
440                 } else {
441                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
442                 }
443             }
444
445             mismatch ^= level;
446             block[j]  = level;
447             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
448                 break;
449             UPDATE_CACHE(re, &s->gb);
450         }
451 end:
452         LAST_SKIP_BITS(re, &s->gb, 2);
453         CLOSE_READER(re, &s->gb);
454     }
455     block[63] ^= (mismatch & 1);
456
457     s->block_last_index[n] = i;
458     return 0;
459 }
460
461 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
462                                                     int16_t *block, int n)
463 {
464     int level, i, j, run;
465     RLTable *rl              = &ff_rl_mpeg1;
466     uint8_t *const scantable = s->intra_scantable.permutated;
467     const int qscale         = s->qscale;
468     OPEN_READER(re, &s->gb);
469     i = -1;
470
471     // special case for first coefficient, no need to add second VLC table
472     UPDATE_CACHE(re, &s->gb);
473     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
474         level = (3 * qscale) >> 1;
475         if (GET_CACHE(re, &s->gb) & 0x40000000)
476             level = -level;
477         block[0] = level;
478         i++;
479         SKIP_BITS(re, &s->gb, 2);
480         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
481             goto end;
482     }
483
484     /* now quantify & encode AC coefficients */
485     for (;;) {
486         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
487
488         if (level != 0) {
489             i += run;
490             check_scantable_index(s, i);
491             j = scantable[i];
492             level = ((level * 2 + 1) * qscale) >> 1;
493             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
494                     SHOW_SBITS(re, &s->gb, 1);
495             SKIP_BITS(re, &s->gb, 1);
496         } else {
497             /* escape */
498             run = SHOW_UBITS(re, &s->gb, 6) + 1;
499             LAST_SKIP_BITS(re, &s->gb, 6);
500             UPDATE_CACHE(re, &s->gb);
501             level = SHOW_SBITS(re, &s->gb, 12);
502             SKIP_BITS(re, &s->gb, 12);
503
504             i += run;
505             check_scantable_index(s, i);
506             j = scantable[i];
507             if (level < 0) {
508                 level = ((-level * 2 + 1) * qscale) >> 1;
509                 level = -level;
510             } else {
511                 level = ((level * 2 + 1) * qscale) >> 1;
512             }
513         }
514
515         block[j] = level;
516         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
517             break;
518         UPDATE_CACHE(re, &s->gb);
519     }
520 end:
521     LAST_SKIP_BITS(re, &s->gb, 2);
522     CLOSE_READER(re, &s->gb);
523     s->block_last_index[n] = i;
524     return 0;
525 }
526
527 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
528                                            int16_t *block, int n)
529 {
530     int level, dc, diff, i, j, run;
531     int component;
532     RLTable *rl;
533     uint8_t *const scantable = s->intra_scantable.permutated;
534     const uint16_t *quant_matrix;
535     const int qscale = s->qscale;
536     int mismatch;
537
538     /* DC coefficient */
539     if (n < 4) {
540         quant_matrix = s->intra_matrix;
541         component    = 0;
542     } else {
543         quant_matrix = s->chroma_intra_matrix;
544         component    = (n & 1) + 1;
545     }
546     diff = decode_dc(&s->gb, component);
547     if (diff >= 0xffff)
548         return AVERROR_INVALIDDATA;
549     dc  = s->last_dc[component];
550     dc += diff;
551     s->last_dc[component] = dc;
552     block[0] = dc << (3 - s->intra_dc_precision);
553     av_dlog(s->avctx, "dc=%d\n", block[0]);
554     mismatch = block[0] ^ 1;
555     i = 0;
556     if (s->intra_vlc_format)
557         rl = &ff_rl_mpeg2;
558     else
559         rl = &ff_rl_mpeg1;
560
561     {
562         OPEN_READER(re, &s->gb);
563         /* now quantify & encode AC coefficients */
564         for (;;) {
565             UPDATE_CACHE(re, &s->gb);
566             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
567                        TEX_VLC_BITS, 2, 0);
568
569             if (level == 127) {
570                 break;
571             } else if (level != 0) {
572                 i += run;
573                 check_scantable_index(s, i);
574                 j = scantable[i];
575                 level = (level * qscale * quant_matrix[j]) >> 4;
576                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
577                         SHOW_SBITS(re, &s->gb, 1);
578                 LAST_SKIP_BITS(re, &s->gb, 1);
579             } else {
580                 /* escape */
581                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
582                 LAST_SKIP_BITS(re, &s->gb, 6);
583                 UPDATE_CACHE(re, &s->gb);
584                 level = SHOW_SBITS(re, &s->gb, 12);
585                 SKIP_BITS(re, &s->gb, 12);
586                 i += run;
587                 check_scantable_index(s, i);
588                 j = scantable[i];
589                 if (level < 0) {
590                     level = (-level * qscale * quant_matrix[j]) >> 4;
591                     level = -level;
592                 } else {
593                     level = (level * qscale * quant_matrix[j]) >> 4;
594                 }
595             }
596
597             mismatch ^= level;
598             block[j]  = level;
599         }
600         CLOSE_READER(re, &s->gb);
601     }
602     block[63] ^= mismatch & 1;
603
604     s->block_last_index[n] = i;
605     return 0;
606 }
607
608 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
609                                                 int16_t *block, int n)
610 {
611     int level, dc, diff, i, j, run;
612     int component;
613     RLTable *rl;
614     uint8_t *const scantable = s->intra_scantable.permutated;
615     const uint16_t *quant_matrix;
616     const int qscale = s->qscale;
617
618     /* DC coefficient */
619     if (n < 4) {
620         quant_matrix = s->intra_matrix;
621         component    = 0;
622     } else {
623         quant_matrix = s->chroma_intra_matrix;
624         component    = (n & 1) + 1;
625     }
626     diff = decode_dc(&s->gb, component);
627     if (diff >= 0xffff)
628         return AVERROR_INVALIDDATA;
629     dc = s->last_dc[component];
630     dc += diff;
631     s->last_dc[component] = dc;
632     block[0] = dc << (3 - s->intra_dc_precision);
633     i = 0;
634     if (s->intra_vlc_format)
635         rl = &ff_rl_mpeg2;
636     else
637         rl = &ff_rl_mpeg1;
638
639     {
640         OPEN_READER(re, &s->gb);
641         /* now quantify & encode AC coefficients */
642         for (;;) {
643             UPDATE_CACHE(re, &s->gb);
644             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
645                        TEX_VLC_BITS, 2, 0);
646
647             if (level == 127) {
648                 break;
649             } else if (level != 0) {
650                 i += run;
651                 check_scantable_index(s, i);
652                 j = scantable[i];
653                 level = (level * qscale * quant_matrix[j]) >> 4;
654                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
655                         SHOW_SBITS(re, &s->gb, 1);
656                 LAST_SKIP_BITS(re, &s->gb, 1);
657             } else {
658                 /* escape */
659                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
660                 LAST_SKIP_BITS(re, &s->gb, 6);
661                 UPDATE_CACHE(re, &s->gb);
662                 level = SHOW_SBITS(re, &s->gb, 12);
663                 SKIP_BITS(re, &s->gb, 12);
664                 i += run;
665                 check_scantable_index(s, i);
666                 j = scantable[i];
667                 if (level < 0) {
668                     level = (-level * qscale * quant_matrix[j]) >> 4;
669                     level = -level;
670                 } else {
671                     level = (level * qscale * quant_matrix[j]) >> 4;
672                 }
673             }
674
675             block[j] = level;
676         }
677         CLOSE_READER(re, &s->gb);
678     }
679
680     s->block_last_index[n] = i;
681     return 0;
682 }
683
684 /******************************************/
685 /* decoding */
686
687 static inline int get_dmv(MpegEncContext *s)
688 {
689     if (get_bits1(&s->gb))
690         return 1 - (get_bits1(&s->gb) << 1);
691     else
692         return 0;
693 }
694
695 static inline int get_qscale(MpegEncContext *s)
696 {
697     int qscale = get_bits(&s->gb, 5);
698     if (s->q_scale_type)
699         return non_linear_qscale[qscale];
700     else
701         return qscale << 1;
702 }
703
704 /* motion type (for MPEG-2) */
705 #define MT_FIELD 1
706 #define MT_FRAME 2
707 #define MT_16X8  2
708 #define MT_DMV   3
709
710 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
711 {
712     int i, j, k, cbp, val, mb_type, motion_type;
713     const int mb_block_count = 4 + (1 << s->chroma_format);
714     int ret;
715
716     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
717
718     assert(s->mb_skipped == 0);
719
720     if (s->mb_skip_run-- != 0) {
721         if (s->pict_type == AV_PICTURE_TYPE_P) {
722             s->mb_skipped = 1;
723             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
724                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
725         } else {
726             int mb_type;
727
728             if (s->mb_x)
729                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
730             else
731                 // FIXME not sure if this is allowed in MPEG at all
732                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
733             if (IS_INTRA(mb_type))
734                 return AVERROR_INVALIDDATA;
735             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
736                 mb_type | MB_TYPE_SKIP;
737 //            assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
738
739             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
740                 s->mb_skipped = 1;
741         }
742
743         return 0;
744     }
745
746     switch (s->pict_type) {
747     default:
748     case AV_PICTURE_TYPE_I:
749         if (get_bits1(&s->gb) == 0) {
750             if (get_bits1(&s->gb) == 0) {
751                 av_log(s->avctx, AV_LOG_ERROR,
752                        "invalid mb type in I Frame at %d %d\n",
753                        s->mb_x, s->mb_y);
754                 return AVERROR_INVALIDDATA;
755             }
756             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
757         } else {
758             mb_type = MB_TYPE_INTRA;
759         }
760         break;
761     case AV_PICTURE_TYPE_P:
762         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
763         if (mb_type < 0) {
764             av_log(s->avctx, AV_LOG_ERROR,
765                    "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
766             return AVERROR_INVALIDDATA;
767         }
768         mb_type = ptype2mb_type[mb_type];
769         break;
770     case AV_PICTURE_TYPE_B:
771         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
772         if (mb_type < 0) {
773             av_log(s->avctx, AV_LOG_ERROR,
774                    "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
775             return AVERROR_INVALIDDATA;
776         }
777         mb_type = btype2mb_type[mb_type];
778         break;
779     }
780     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
781 //    motion_type = 0; /* avoid warning */
782     if (IS_INTRA(mb_type)) {
783         s->bdsp.clear_blocks(s->block[0]);
784
785         if (!s->chroma_y_shift)
786             s->bdsp.clear_blocks(s->block[6]);
787
788         /* compute DCT type */
789         // FIXME: add an interlaced_dct coded var?
790         if (s->picture_structure == PICT_FRAME &&
791             !s->frame_pred_frame_dct)
792             s->interlaced_dct = get_bits1(&s->gb);
793
794         if (IS_QUANT(mb_type))
795             s->qscale = get_qscale(s);
796
797         if (s->concealment_motion_vectors) {
798             /* just parse them */
799             if (s->picture_structure != PICT_FRAME)
800                 skip_bits1(&s->gb);  /* field select */
801
802             s->mv[0][0][0]      =
803             s->last_mv[0][0][0] =
804             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
805                                                      s->last_mv[0][0][0]);
806             s->mv[0][0][1]      =
807             s->last_mv[0][0][1] =
808             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
809                                                      s->last_mv[0][0][1]);
810
811             skip_bits1(&s->gb); /* marker */
812         } else {
813             /* reset mv prediction */
814             memset(s->last_mv, 0, sizeof(s->last_mv));
815         }
816         s->mb_intra = 1;
817 #if FF_API_XVMC
818 FF_DISABLE_DEPRECATION_WARNINGS
819         // if 1, we memcpy blocks in xvmcvideo
820         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
821             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
822 FF_ENABLE_DEPRECATION_WARNINGS
823 #endif /* FF_API_XVMC */
824
825         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
826             if (s->flags2 & CODEC_FLAG2_FAST) {
827                 for (i = 0; i < 6; i++)
828                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
829             } else {
830                 for (i = 0; i < mb_block_count; i++)
831                     if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
832                         return ret;
833             }
834         } else {
835             for (i = 0; i < 6; i++)
836                 if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0)
837                     return ret;
838         }
839     } else {
840         if (mb_type & MB_TYPE_ZERO_MV) {
841             assert(mb_type & MB_TYPE_CBP);
842
843             s->mv_dir = MV_DIR_FORWARD;
844             if (s->picture_structure == PICT_FRAME) {
845                 if (!s->frame_pred_frame_dct)
846                     s->interlaced_dct = get_bits1(&s->gb);
847                 s->mv_type = MV_TYPE_16X16;
848             } else {
849                 s->mv_type            = MV_TYPE_FIELD;
850                 mb_type              |= MB_TYPE_INTERLACED;
851                 s->field_select[0][0] = s->picture_structure - 1;
852             }
853
854             if (IS_QUANT(mb_type))
855                 s->qscale = get_qscale(s);
856
857             s->last_mv[0][0][0] = 0;
858             s->last_mv[0][0][1] = 0;
859             s->last_mv[0][1][0] = 0;
860             s->last_mv[0][1][1] = 0;
861             s->mv[0][0][0]      = 0;
862             s->mv[0][0][1]      = 0;
863         } else {
864             assert(mb_type & MB_TYPE_L0L1);
865             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
866             /* get additional motion vector type */
867             if (s->frame_pred_frame_dct) {
868                 motion_type = MT_FRAME;
869             } else {
870                 motion_type = get_bits(&s->gb, 2);
871                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
872                     s->interlaced_dct = get_bits1(&s->gb);
873             }
874
875             if (IS_QUANT(mb_type))
876                 s->qscale = get_qscale(s);
877
878             /* motion vectors */
879             s->mv_dir = (mb_type >> 13) & 3;
880             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
881             switch (motion_type) {
882             case MT_FRAME: /* or MT_16X8 */
883                 if (s->picture_structure == PICT_FRAME) {
884                     mb_type   |= MB_TYPE_16x16;
885                     s->mv_type = MV_TYPE_16X16;
886                     for (i = 0; i < 2; i++) {
887                         if (USES_LIST(mb_type, i)) {
888                             /* MT_FRAME */
889                             s->mv[i][0][0]      =
890                             s->last_mv[i][0][0] =
891                             s->last_mv[i][1][0] =
892                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
893                                                    s->last_mv[i][0][0]);
894                             s->mv[i][0][1]      =
895                             s->last_mv[i][0][1] =
896                             s->last_mv[i][1][1] =
897                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
898                                                    s->last_mv[i][0][1]);
899                             /* full_pel: only for MPEG-1 */
900                             if (s->full_pel[i]) {
901                                 s->mv[i][0][0] <<= 1;
902                                 s->mv[i][0][1] <<= 1;
903                             }
904                         }
905                     }
906                 } else {
907                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
908                     s->mv_type = MV_TYPE_16X8;
909                     for (i = 0; i < 2; i++) {
910                         if (USES_LIST(mb_type, i)) {
911                             /* MT_16X8 */
912                             for (j = 0; j < 2; j++) {
913                                 s->field_select[i][j] = get_bits1(&s->gb);
914                                 for (k = 0; k < 2; k++) {
915                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
916                                                              s->last_mv[i][j][k]);
917                                     s->last_mv[i][j][k] = val;
918                                     s->mv[i][j][k]      = val;
919                                 }
920                             }
921                         }
922                     }
923                 }
924                 break;
925             case MT_FIELD:
926                 s->mv_type = MV_TYPE_FIELD;
927                 if (s->picture_structure == PICT_FRAME) {
928                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
929                     for (i = 0; i < 2; i++) {
930                         if (USES_LIST(mb_type, i)) {
931                             for (j = 0; j < 2; j++) {
932                                 s->field_select[i][j] = get_bits1(&s->gb);
933                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
934                                                          s->last_mv[i][j][0]);
935                                 s->last_mv[i][j][0] = val;
936                                 s->mv[i][j][0]      = val;
937                                 av_dlog(s->avctx, "fmx=%d\n", val);
938                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
939                                                          s->last_mv[i][j][1] >> 1);
940                                 s->last_mv[i][j][1] = val << 1;
941                                 s->mv[i][j][1]      = val;
942                                 av_dlog(s->avctx, "fmy=%d\n", val);
943                             }
944                         }
945                     }
946                 } else {
947                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
948                     for (i = 0; i < 2; i++) {
949                         if (USES_LIST(mb_type, i)) {
950                             s->field_select[i][0] = get_bits1(&s->gb);
951                             for (k = 0; k < 2; k++) {
952                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
953                                                          s->last_mv[i][0][k]);
954                                 s->last_mv[i][0][k] = val;
955                                 s->last_mv[i][1][k] = val;
956                                 s->mv[i][0][k]      = val;
957                             }
958                         }
959                     }
960                 }
961                 break;
962             case MT_DMV:
963                 s->mv_type = MV_TYPE_DMV;
964                 for (i = 0; i < 2; i++) {
965                     if (USES_LIST(mb_type, i)) {
966                         int dmx, dmy, mx, my, m;
967                         const int my_shift = s->picture_structure == PICT_FRAME;
968
969                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
970                                                 s->last_mv[i][0][0]);
971                         s->last_mv[i][0][0] = mx;
972                         s->last_mv[i][1][0] = mx;
973                         dmx = get_dmv(s);
974                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
975                                                  s->last_mv[i][0][1] >> my_shift);
976                         dmy = get_dmv(s);
977
978
979                         s->last_mv[i][0][1] = my << my_shift;
980                         s->last_mv[i][1][1] = my << my_shift;
981
982                         s->mv[i][0][0] = mx;
983                         s->mv[i][0][1] = my;
984                         s->mv[i][1][0] = mx; // not used
985                         s->mv[i][1][1] = my; // not used
986
987                         if (s->picture_structure == PICT_FRAME) {
988                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
989
990                             // m = 1 + 2 * s->top_field_first;
991                             m = s->top_field_first ? 1 : 3;
992
993                             /* top -> top pred */
994                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
995                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
996                             m = 4 - m;
997                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
998                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
999                         } else {
1000                             mb_type |= MB_TYPE_16x16;
1001
1002                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1003                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1004                             if (s->picture_structure == PICT_TOP_FIELD)
1005                                 s->mv[i][2][1]--;
1006                             else
1007                                 s->mv[i][2][1]++;
1008                         }
1009                     }
1010                 }
1011                 break;
1012             default:
1013                 av_log(s->avctx, AV_LOG_ERROR,
1014                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1015                 return AVERROR_INVALIDDATA;
1016             }
1017         }
1018
1019         s->mb_intra = 0;
1020         if (HAS_CBP(mb_type)) {
1021             s->bdsp.clear_blocks(s->block[0]);
1022
1023             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1024             if (mb_block_count > 6) {
1025                 cbp <<= mb_block_count - 6;
1026                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
1027                 s->bdsp.clear_blocks(s->block[6]);
1028             }
1029             if (cbp <= 0) {
1030                 av_log(s->avctx, AV_LOG_ERROR,
1031                        "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
1032                 return AVERROR_INVALIDDATA;
1033             }
1034
1035 #if FF_API_XVMC
1036 FF_DISABLE_DEPRECATION_WARNINGS
1037             // if 1, we memcpy blocks in xvmcvideo
1038             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1039                 ff_xvmc_pack_pblocks(s, cbp);
1040 FF_ENABLE_DEPRECATION_WARNINGS
1041 #endif /* FF_API_XVMC */
1042
1043             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1044                 if (s->flags2 & CODEC_FLAG2_FAST) {
1045                     for (i = 0; i < 6; i++) {
1046                         if (cbp & 32)
1047                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1048                         else
1049                             s->block_last_index[i] = -1;
1050                         cbp += cbp;
1051                     }
1052                 } else {
1053                     cbp <<= 12 - mb_block_count;
1054
1055                     for (i = 0; i < mb_block_count; i++) {
1056                         if (cbp & (1 << 11)) {
1057                             if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
1058                                 return ret;
1059                         } else {
1060                             s->block_last_index[i] = -1;
1061                         }
1062                         cbp += cbp;
1063                     }
1064                 }
1065             } else {
1066                 if (s->flags2 & CODEC_FLAG2_FAST) {
1067                     for (i = 0; i < 6; i++) {
1068                         if (cbp & 32)
1069                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1070                         else
1071                             s->block_last_index[i] = -1;
1072                         cbp += cbp;
1073                     }
1074                 } else {
1075                     for (i = 0; i < 6; i++) {
1076                         if (cbp & 32) {
1077                             if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
1078                                 return ret;
1079                         } else {
1080                             s->block_last_index[i] = -1;
1081                         }
1082                         cbp += cbp;
1083                     }
1084                 }
1085             }
1086         } else {
1087             for (i = 0; i < 12; i++)
1088                 s->block_last_index[i] = -1;
1089         }
1090     }
1091
1092     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1093
1094     return 0;
1095 }
1096
1097 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1098 {
1099     Mpeg1Context *s    = avctx->priv_data;
1100     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1101
1102     ff_mpv_decode_defaults(s2);
1103
1104     s->mpeg_enc_ctx.avctx  = avctx;
1105     s->mpeg_enc_ctx.flags  = avctx->flags;
1106     s->mpeg_enc_ctx.flags2 = avctx->flags2;
1107
1108     /* we need some permutation to store matrices,
1109      * until the decoder sets the real permutation. */
1110     ff_mpv_idct_init(s2);
1111     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1112     ff_mpeg12_init_vlcs();
1113
1114     s->mpeg_enc_ctx_allocated      = 0;
1115     s->mpeg_enc_ctx.picture_number = 0;
1116     s->repeat_field                = 0;
1117     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1118     avctx->color_range             = AVCOL_RANGE_MPEG;
1119     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1120         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1121     else
1122         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1123     return 0;
1124 }
1125
1126 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1127                                              const AVCodecContext *avctx_from)
1128 {
1129     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1130     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1131     int err;
1132
1133     if (avctx == avctx_from               ||
1134         !ctx_from->mpeg_enc_ctx_allocated ||
1135         !s1->context_initialized)
1136         return 0;
1137
1138     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1139     if (err)
1140         return err;
1141
1142     if (!ctx->mpeg_enc_ctx_allocated) {
1143         // copy the whole context after the initial MpegEncContext structure
1144         memcpy(ctx, ctx_from, sizeof(*ctx));
1145         memset(&ctx->mpeg_enc_ctx, 0, sizeof(ctx->mpeg_enc_ctx));
1146     }
1147
1148     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1149         s->picture_number++;
1150
1151     return 0;
1152 }
1153
1154 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1155                                  const uint8_t *new_perm)
1156 {
1157     uint16_t temp_matrix[64];
1158     int i;
1159
1160     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1161
1162     for (i = 0; i < 64; i++)
1163         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1164 }
1165
1166 #if FF_API_XVMC
1167 static const enum AVPixelFormat pixfmt_xvmc_mpg2_420[] = {
1168     AV_PIX_FMT_XVMC_MPEG2_IDCT,
1169     AV_PIX_FMT_XVMC_MPEG2_MC,
1170     AV_PIX_FMT_NONE
1171 };
1172 #endif /* FF_API_XVMC */
1173
1174 static const enum AVPixelFormat mpeg12_hwaccel_pixfmt_list_420[] = {
1175 #if CONFIG_MPEG2_DXVA2_HWACCEL
1176     AV_PIX_FMT_DXVA2_VLD,
1177 #endif
1178 #if CONFIG_MPEG2_VAAPI_HWACCEL
1179     AV_PIX_FMT_VAAPI_VLD,
1180 #endif
1181 #if CONFIG_MPEG1_VDPAU_HWACCEL | CONFIG_MPEG2_VDPAU_HWACCEL
1182     AV_PIX_FMT_VDPAU,
1183 #endif
1184     AV_PIX_FMT_YUV420P,
1185     AV_PIX_FMT_NONE
1186 };
1187
1188 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1189     AV_PIX_FMT_YUV422P,
1190     AV_PIX_FMT_NONE
1191 };
1192
1193 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1194     AV_PIX_FMT_YUV444P,
1195     AV_PIX_FMT_NONE
1196 };
1197
1198 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1199 {
1200     Mpeg1Context *s1  = avctx->priv_data;
1201     MpegEncContext *s = &s1->mpeg_enc_ctx;
1202     const enum AVPixelFormat *pix_fmts;
1203
1204 #if FF_API_XVMC
1205 FF_DISABLE_DEPRECATION_WARNINGS
1206     if (avctx->xvmc_acceleration)
1207         return ff_get_format(avctx, pixfmt_xvmc_mpg2_420);
1208 FF_ENABLE_DEPRECATION_WARNINGS
1209 #endif /* FF_API_XVMC */
1210
1211     if (s->chroma_format < 2)
1212         pix_fmts = mpeg12_hwaccel_pixfmt_list_420;
1213     else if (s->chroma_format == 2)
1214         pix_fmts = mpeg12_pixfmt_list_422;
1215     else
1216         pix_fmts = mpeg12_pixfmt_list_444;
1217
1218     return ff_get_format(avctx, pix_fmts);
1219 }
1220
1221 /* Call this function when we know all parameters.
1222  * It may be called in different places for MPEG-1 and MPEG-2. */
1223 static int mpeg_decode_postinit(AVCodecContext *avctx)
1224 {
1225     Mpeg1Context *s1  = avctx->priv_data;
1226     MpegEncContext *s = &s1->mpeg_enc_ctx;
1227     uint8_t old_permutation[64];
1228     int ret;
1229
1230     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1231         avctx->coded_width       != s->width                ||
1232         avctx->coded_height      != s->height               ||
1233         s1->save_width           != s->width                ||
1234         s1->save_height          != s->height               ||
1235         s1->save_aspect_info     != s->aspect_ratio_info    ||
1236         s1->save_progressive_seq != s->progressive_sequence ||
1237         0) {
1238         if (s1->mpeg_enc_ctx_allocated) {
1239             ParseContext pc = s->parse_context;
1240             s->parse_context.buffer = 0;
1241             ff_mpv_common_end(s);
1242             s->parse_context = pc;
1243         }
1244
1245         ret = ff_set_dimensions(avctx, s->width, s->height);
1246         if (ret < 0)
1247             return ret;
1248
1249         avctx->bit_rate          = s->bit_rate;
1250         s1->save_aspect_info     = s->aspect_ratio_info;
1251         s1->save_width           = s->width;
1252         s1->save_height          = s->height;
1253         s1->save_progressive_seq = s->progressive_sequence;
1254
1255         /* low_delay may be forced, in this case we will have B-frames
1256          * that behave like P-frames. */
1257         avctx->has_b_frames = !s->low_delay;
1258
1259         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1260             // MPEG-1 fps
1261             avctx->framerate = ff_mpeg12_frame_rate_tab[s->frame_rate_index];
1262             // MPEG-1 aspect
1263             avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1264             avctx->ticks_per_frame     = 1;
1265         } else { // MPEG-2
1266             // MPEG-2 fps
1267             av_reduce(&s->avctx->framerate.num,
1268                       &s->avctx->framerate.den,
1269                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num * 2,
1270                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1271                       1 << 30);
1272             avctx->ticks_per_frame = 2;
1273             // MPEG-2 aspect
1274             if (s->aspect_ratio_info > 1) {
1275                 AVRational dar =
1276                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1277                                       (AVRational) { s1->pan_scan.width,
1278                                                      s1->pan_scan.height }),
1279                              (AVRational) { s->width, s->height });
1280
1281                 /* We ignore the spec here and guess a bit as reality does not
1282                  * match the spec, see for example res_change_ffmpeg_aspect.ts
1283                  * and sequence-display-aspect.mpg.
1284                  * issue1613, 621, 562 */
1285                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1286                     (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1287                      av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1288                     s->avctx->sample_aspect_ratio =
1289                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1290                                  (AVRational) { s->width, s->height });
1291                 } else {
1292                     s->avctx->sample_aspect_ratio =
1293                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1294                                  (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1295 // issue1613 4/3 16/9 -> 16/9
1296 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1297 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1298 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1299                     av_dlog(avctx, "A %d/%d\n",
1300                             ff_mpeg2_aspect[s->aspect_ratio_info].num,
1301                             ff_mpeg2_aspect[s->aspect_ratio_info].den);
1302                     av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1303                             s->avctx->sample_aspect_ratio.den);
1304                 }
1305             } else {
1306                 s->avctx->sample_aspect_ratio =
1307                     ff_mpeg2_aspect[s->aspect_ratio_info];
1308             }
1309         } // MPEG-2
1310
1311         ff_set_sar(s->avctx, s->avctx->sample_aspect_ratio);
1312
1313         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1314         // until then pix_fmt may be changed right after codec init
1315 #if FF_API_XVMC
1316         if ((avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT ||
1317              avctx->hwaccel) && avctx->idct_algo == FF_IDCT_AUTO)
1318 #else
1319         if (avctx->hwaccel && avctx->idct_algo == FF_IDCT_AUTO)
1320 #endif /* FF_API_XVMC */
1321             avctx->idct_algo = FF_IDCT_SIMPLE;
1322
1323         /* Quantization matrices may need reordering
1324          * if DCT permutation is changed. */
1325         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1326
1327         ff_mpv_idct_init(s);
1328         if ((ret = ff_mpv_common_init(s)) < 0)
1329             return ret;
1330
1331         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1332         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1333         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1334         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1335
1336         s1->mpeg_enc_ctx_allocated = 1;
1337     }
1338     return 0;
1339 }
1340
1341 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1342                                 int buf_size)
1343 {
1344     Mpeg1Context *s1  = avctx->priv_data;
1345     MpegEncContext *s = &s1->mpeg_enc_ctx;
1346     int ref, f_code, vbv_delay;
1347
1348     init_get_bits(&s->gb, buf, buf_size * 8);
1349
1350     ref = get_bits(&s->gb, 10); /* temporal ref */
1351     s->pict_type = get_bits(&s->gb, 3);
1352     if (s->pict_type == 0 || s->pict_type > 3)
1353         return AVERROR_INVALIDDATA;
1354
1355     vbv_delay = get_bits(&s->gb, 16);
1356     if (s->pict_type == AV_PICTURE_TYPE_P ||
1357         s->pict_type == AV_PICTURE_TYPE_B) {
1358         s->full_pel[0] = get_bits1(&s->gb);
1359         f_code = get_bits(&s->gb, 3);
1360         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1361             return AVERROR_INVALIDDATA;
1362         s->mpeg_f_code[0][0] = f_code;
1363         s->mpeg_f_code[0][1] = f_code;
1364     }
1365     if (s->pict_type == AV_PICTURE_TYPE_B) {
1366         s->full_pel[1] = get_bits1(&s->gb);
1367         f_code = get_bits(&s->gb, 3);
1368         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1369             return AVERROR_INVALIDDATA;
1370         s->mpeg_f_code[1][0] = f_code;
1371         s->mpeg_f_code[1][1] = f_code;
1372     }
1373     s->current_picture.f->pict_type = s->pict_type;
1374     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1375
1376     if (avctx->debug & FF_DEBUG_PICT_INFO)
1377         av_log(avctx, AV_LOG_DEBUG,
1378                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1379
1380     s->y_dc_scale = 8;
1381     s->c_dc_scale = 8;
1382     return 0;
1383 }
1384
1385 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1386 {
1387     MpegEncContext *s = &s1->mpeg_enc_ctx;
1388     int horiz_size_ext, vert_size_ext;
1389     int bit_rate_ext;
1390
1391     skip_bits(&s->gb, 1); /* profile and level esc*/
1392     s->avctx->profile       = get_bits(&s->gb, 3);
1393     s->avctx->level         = get_bits(&s->gb, 4);
1394     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1395     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1396     horiz_size_ext          = get_bits(&s->gb, 2);
1397     vert_size_ext           = get_bits(&s->gb, 2);
1398     s->width  |= (horiz_size_ext << 12);
1399     s->height |= (vert_size_ext  << 12);
1400     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1401     s->bit_rate += (bit_rate_ext << 18) * 400;
1402     skip_bits1(&s->gb); /* marker */
1403     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1404
1405     s->low_delay = get_bits1(&s->gb);
1406     if (s->flags & CODEC_FLAG_LOW_DELAY)
1407         s->low_delay = 1;
1408
1409     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1410     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1411
1412     av_dlog(s->avctx, "sequence extension\n");
1413     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1414
1415     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1416         av_log(s->avctx, AV_LOG_DEBUG,
1417                "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1418                s->avctx->profile, s->avctx->level,
1419                s->avctx->rc_buffer_size, s->bit_rate);
1420 }
1421
1422 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1423 {
1424     MpegEncContext *s = &s1->mpeg_enc_ctx;
1425     int color_description, w, h;
1426
1427     skip_bits(&s->gb, 3); /* video format */
1428     color_description = get_bits1(&s->gb);
1429     if (color_description) {
1430         s->avctx->color_primaries = get_bits(&s->gb, 8);
1431         s->avctx->color_trc       = get_bits(&s->gb, 8);
1432         s->avctx->colorspace      = get_bits(&s->gb, 8);
1433     }
1434     w = get_bits(&s->gb, 14);
1435     skip_bits(&s->gb, 1); // marker
1436     h = get_bits(&s->gb, 14);
1437     // remaining 3 bits are zero padding
1438
1439     s1->pan_scan.width  = 16 * w;
1440     s1->pan_scan.height = 16 * h;
1441
1442     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1443         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1444 }
1445
1446 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1447 {
1448     MpegEncContext *s = &s1->mpeg_enc_ctx;
1449     int i, nofco;
1450
1451     nofco = 1;
1452     if (s->progressive_sequence) {
1453         if (s->repeat_first_field) {
1454             nofco++;
1455             if (s->top_field_first)
1456                 nofco++;
1457         }
1458     } else {
1459         if (s->picture_structure == PICT_FRAME) {
1460             nofco++;
1461             if (s->repeat_first_field)
1462                 nofco++;
1463         }
1464     }
1465     for (i = 0; i < nofco; i++) {
1466         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1467         skip_bits(&s->gb, 1); // marker
1468         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1469         skip_bits(&s->gb, 1); // marker
1470     }
1471
1472     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1473         av_log(s->avctx, AV_LOG_DEBUG,
1474                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1475                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1476                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1477                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1478 }
1479
1480 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1481                        uint16_t matrix1[64], int intra)
1482 {
1483     int i;
1484
1485     for (i = 0; i < 64; i++) {
1486         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1487         int v = get_bits(&s->gb, 8);
1488         if (v == 0) {
1489             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1490             return AVERROR_INVALIDDATA;
1491         }
1492         if (intra && i == 0 && v != 8) {
1493             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1494             v = 8; // needed by pink.mpg / issue1046
1495         }
1496         matrix0[j] = v;
1497         if (matrix1)
1498             matrix1[j] = v;
1499     }
1500     return 0;
1501 }
1502
1503 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1504 {
1505     av_dlog(s->avctx, "matrix extension\n");
1506
1507     if (get_bits1(&s->gb))
1508         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1509     if (get_bits1(&s->gb))
1510         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1511     if (get_bits1(&s->gb))
1512         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1513     if (get_bits1(&s->gb))
1514         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1515 }
1516
1517 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1518 {
1519     MpegEncContext *s = &s1->mpeg_enc_ctx;
1520
1521     s->full_pel[0]       = s->full_pel[1] = 0;
1522     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1523     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1524     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1525     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1526     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1527         av_log(s->avctx, AV_LOG_ERROR,
1528                "Missing picture start code, guessing missing values\n");
1529         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1530             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1531                 s->pict_type = AV_PICTURE_TYPE_I;
1532             else
1533                 s->pict_type = AV_PICTURE_TYPE_P;
1534         } else
1535             s->pict_type = AV_PICTURE_TYPE_B;
1536         s->current_picture.f->pict_type = s->pict_type;
1537         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1538     }
1539     s->intra_dc_precision         = get_bits(&s->gb, 2);
1540     s->picture_structure          = get_bits(&s->gb, 2);
1541     s->top_field_first            = get_bits1(&s->gb);
1542     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1543     s->concealment_motion_vectors = get_bits1(&s->gb);
1544     s->q_scale_type               = get_bits1(&s->gb);
1545     s->intra_vlc_format           = get_bits1(&s->gb);
1546     s->alternate_scan             = get_bits1(&s->gb);
1547     s->repeat_first_field         = get_bits1(&s->gb);
1548     s->chroma_420_type            = get_bits1(&s->gb);
1549     s->progressive_frame          = get_bits1(&s->gb);
1550
1551     if (s->progressive_sequence && !s->progressive_frame) {
1552         s->progressive_frame = 1;
1553         av_log(s->avctx, AV_LOG_ERROR,
1554                "interlaced frame in progressive sequence, ignoring\n");
1555     }
1556
1557     if (s->picture_structure == 0 ||
1558         (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
1559         av_log(s->avctx, AV_LOG_ERROR,
1560                "picture_structure %d invalid, ignoring\n",
1561                s->picture_structure);
1562         s->picture_structure = PICT_FRAME;
1563     }
1564
1565     if (s->progressive_sequence && !s->frame_pred_frame_dct)
1566         av_log(s->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
1567
1568     if (s->picture_structure == PICT_FRAME) {
1569         s->first_field = 0;
1570         s->v_edge_pos  = 16 * s->mb_height;
1571     } else {
1572         s->first_field ^= 1;
1573         s->v_edge_pos   = 8 * s->mb_height;
1574         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
1575     }
1576
1577     if (s->alternate_scan) {
1578         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1579         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1580     } else {
1581         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1582         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1583     }
1584
1585     /* composite display not parsed */
1586     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1587     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1588     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1589     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1590     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1591     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1592     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1593     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1594     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1595 }
1596
1597 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1598 {
1599     AVCodecContext *avctx = s->avctx;
1600     Mpeg1Context *s1      = (Mpeg1Context *) s;
1601     int ret;
1602
1603     /* start frame decoding */
1604     if (s->first_field || s->picture_structure == PICT_FRAME) {
1605         AVFrameSideData *pan_scan;
1606
1607         if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
1608             return ret;
1609
1610         ff_mpeg_er_frame_start(s);
1611
1612         /* first check if we must repeat the frame */
1613         s->current_picture_ptr->f->repeat_pict = 0;
1614         if (s->repeat_first_field) {
1615             if (s->progressive_sequence) {
1616                 if (s->top_field_first)
1617                     s->current_picture_ptr->f->repeat_pict = 4;
1618                 else
1619                     s->current_picture_ptr->f->repeat_pict = 2;
1620             } else if (s->progressive_frame) {
1621                 s->current_picture_ptr->f->repeat_pict = 1;
1622             }
1623         }
1624
1625         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1626                                           AV_FRAME_DATA_PANSCAN,
1627                                           sizeof(s1->pan_scan));
1628         if (!pan_scan)
1629             return AVERROR(ENOMEM);
1630         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1631
1632         if (s1->a53_caption) {
1633             AVFrameSideData *sd = av_frame_new_side_data(
1634                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1635                 s1->a53_caption_size);
1636             if (sd)
1637                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1638             av_freep(&s1->a53_caption);
1639         }
1640
1641         if (s1->has_stereo3d) {
1642             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1643             if (!stereo)
1644                 return AVERROR(ENOMEM);
1645
1646             *stereo = s1->stereo3d;
1647             s1->has_stereo3d = 0;
1648         }
1649
1650         if (s1->has_afd) {
1651             AVFrameSideData *sd =
1652                 av_frame_new_side_data(s->current_picture_ptr->f,
1653                                        AV_FRAME_DATA_AFD, 1);
1654             if (!sd)
1655                 return AVERROR(ENOMEM);
1656
1657             *sd->data   = s1->afd;
1658             s1->has_afd = 0;
1659         }
1660
1661         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1662             ff_thread_finish_setup(avctx);
1663     } else { // second field
1664         int i;
1665
1666         if (!s->current_picture_ptr) {
1667             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1668             return AVERROR_INVALIDDATA;
1669         }
1670
1671         if (s->avctx->hwaccel &&
1672             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1673             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1674                 av_log(avctx, AV_LOG_ERROR,
1675                        "hardware accelerator failed to decode first field\n");
1676         }
1677
1678         for (i = 0; i < 4; i++) {
1679             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1680             if (s->picture_structure == PICT_BOTTOM_FIELD)
1681                 s->current_picture.f->data[i] +=
1682                     s->current_picture_ptr->f->linesize[i];
1683         }
1684     }
1685
1686     if (avctx->hwaccel) {
1687         if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
1688             return ret;
1689     }
1690
1691 #if FF_API_XVMC
1692 FF_DISABLE_DEPRECATION_WARNINGS
1693 // ff_mpv_frame_start will call this function too,
1694 // but we need to call it on every field
1695     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1696         if (ff_xvmc_field_start(s, avctx) < 0)
1697             return -1;
1698 FF_ENABLE_DEPRECATION_WARNINGS
1699 #endif /* FF_API_XVMC */
1700
1701     return 0;
1702 }
1703
1704 #define DECODE_SLICE_ERROR -1
1705 #define DECODE_SLICE_OK     0
1706
1707 /**
1708  * Decode a slice.
1709  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1710  * @return DECODE_SLICE_ERROR if the slice is damaged,
1711  *         DECODE_SLICE_OK if this slice is OK
1712  */
1713 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1714                              const uint8_t **buf, int buf_size)
1715 {
1716     AVCodecContext *avctx = s->avctx;
1717     const int field_pic   = s->picture_structure != PICT_FRAME;
1718     int ret;
1719
1720     s->resync_mb_x =
1721     s->resync_mb_y = -1;
1722
1723     assert(mb_y < s->mb_height);
1724
1725     init_get_bits(&s->gb, *buf, buf_size * 8);
1726
1727     ff_mpeg1_clean_buffers(s);
1728     s->interlaced_dct = 0;
1729
1730     s->qscale = get_qscale(s);
1731
1732     if (s->qscale == 0) {
1733         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1734         return AVERROR_INVALIDDATA;
1735     }
1736
1737     /* extra slice info */
1738     while (get_bits1(&s->gb) != 0)
1739         skip_bits(&s->gb, 8);
1740
1741     s->mb_x = 0;
1742
1743     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1744         skip_bits1(&s->gb);
1745     } else {
1746         while (get_bits_left(&s->gb) > 0) {
1747             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1748                                 MBINCR_VLC_BITS, 2);
1749             if (code < 0) {
1750                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1751                 return AVERROR_INVALIDDATA;
1752             }
1753             if (code >= 33) {
1754                 if (code == 33)
1755                     s->mb_x += 33;
1756                 /* otherwise, stuffing, nothing to do */
1757             } else {
1758                 s->mb_x += code;
1759                 break;
1760             }
1761         }
1762     }
1763
1764     if (s->mb_x >= (unsigned) s->mb_width) {
1765         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1766         return AVERROR_INVALIDDATA;
1767     }
1768
1769     if (avctx->hwaccel) {
1770         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1771         int start_code = -1;
1772         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1773         if (buf_end < *buf + buf_size)
1774             buf_end -= 4;
1775         s->mb_y = mb_y;
1776         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1777             return DECODE_SLICE_ERROR;
1778         *buf = buf_end;
1779         return DECODE_SLICE_OK;
1780     }
1781
1782     s->resync_mb_x = s->mb_x;
1783     s->resync_mb_y = s->mb_y = mb_y;
1784     s->mb_skip_run = 0;
1785     ff_init_block_index(s);
1786
1787     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1788         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1789             av_log(s->avctx, AV_LOG_DEBUG,
1790                    "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",
1791                    s->qscale,
1792                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1793                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1794                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1795                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1796                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1797                    s->progressive_sequence ? "ps"  : "",
1798                    s->progressive_frame    ? "pf"  : "",
1799                    s->alternate_scan       ? "alt" : "",
1800                    s->top_field_first      ? "top" : "",
1801                    s->intra_dc_precision, s->picture_structure,
1802                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1803                    s->q_scale_type, s->intra_vlc_format,
1804                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1805         }
1806     }
1807
1808     for (;;) {
1809 #if FF_API_XVMC
1810 FF_DISABLE_DEPRECATION_WARNINGS
1811         // If 1, we memcpy blocks in xvmcvideo.
1812         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1813             ff_xvmc_init_block(s); // set s->block
1814 FF_ENABLE_DEPRECATION_WARNINGS
1815 #endif /* FF_API_XVMC */
1816
1817         if ((ret = mpeg_decode_mb(s, s->block)) < 0)
1818             return ret;
1819
1820         // Note motion_val is normally NULL unless we want to extract the MVs.
1821         if (s->current_picture.motion_val[0] && !s->encoding) {
1822             const int wrap = s->b8_stride;
1823             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1824             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1825             int motion_x, motion_y, dir, i;
1826
1827             for (i = 0; i < 2; i++) {
1828                 for (dir = 0; dir < 2; dir++) {
1829                     if (s->mb_intra ||
1830                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1831                         motion_x = motion_y = 0;
1832                     } else if (s->mv_type == MV_TYPE_16X16 ||
1833                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1834                         motion_x = s->mv[dir][0][0];
1835                         motion_y = s->mv[dir][0][1];
1836                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1837                         motion_x = s->mv[dir][i][0];
1838                         motion_y = s->mv[dir][i][1];
1839                     }
1840
1841                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1842                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1843                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1844                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1845                     s->current_picture.ref_index [dir][b8_xy]     =
1846                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1847                     assert(s->field_select[dir][i] == 0 ||
1848                            s->field_select[dir][i] == 1);
1849                 }
1850                 xy    += wrap;
1851                 b8_xy += 2;
1852             }
1853         }
1854
1855         s->dest[0] += 16;
1856         s->dest[1] += 16 >> s->chroma_x_shift;
1857         s->dest[2] += 16 >> s->chroma_x_shift;
1858
1859         ff_mpv_decode_mb(s, s->block);
1860
1861         if (++s->mb_x >= s->mb_width) {
1862             const int mb_size = 16;
1863
1864             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1865             ff_mpv_report_decode_progress(s);
1866
1867             s->mb_x  = 0;
1868             s->mb_y += 1 << field_pic;
1869
1870             if (s->mb_y >= s->mb_height) {
1871                 int left   = get_bits_left(&s->gb);
1872                 int is_d10 = s->chroma_format == 2 &&
1873                              s->pict_type == AV_PICTURE_TYPE_I &&
1874                              avctx->profile == 0 && avctx->level == 5 &&
1875                              s->intra_dc_precision == 2 &&
1876                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1877                              s->progressive_frame == 0
1878                              /* vbv_delay == 0xBBB || 0xE10 */;
1879
1880                 if (left < 0 ||
1881                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1882                     ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
1883                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1884                            left, show_bits(&s->gb, FFMIN(left, 23)));
1885                     return AVERROR_INVALIDDATA;
1886                 } else
1887                     goto eos;
1888             }
1889
1890             ff_init_block_index(s);
1891         }
1892
1893         /* skip mb handling */
1894         if (s->mb_skip_run == -1) {
1895             /* read increment again */
1896             s->mb_skip_run = 0;
1897             for (;;) {
1898                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1899                                     MBINCR_VLC_BITS, 2);
1900                 if (code < 0) {
1901                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1902                     return AVERROR_INVALIDDATA;
1903                 }
1904                 if (code >= 33) {
1905                     if (code == 33) {
1906                         s->mb_skip_run += 33;
1907                     } else if (code == 35) {
1908                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1909                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1910                             return AVERROR_INVALIDDATA;
1911                         }
1912                         goto eos; /* end of slice */
1913                     }
1914                     /* otherwise, stuffing, nothing to do */
1915                 } else {
1916                     s->mb_skip_run += code;
1917                     break;
1918                 }
1919             }
1920             if (s->mb_skip_run) {
1921                 int i;
1922                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1923                     av_log(s->avctx, AV_LOG_ERROR,
1924                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1925                     return AVERROR_INVALIDDATA;
1926                 }
1927
1928                 /* skip mb */
1929                 s->mb_intra = 0;
1930                 for (i = 0; i < 12; i++)
1931                     s->block_last_index[i] = -1;
1932                 if (s->picture_structure == PICT_FRAME)
1933                     s->mv_type = MV_TYPE_16X16;
1934                 else
1935                     s->mv_type = MV_TYPE_FIELD;
1936                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1937                     /* if P type, zero motion vector is implied */
1938                     s->mv_dir             = MV_DIR_FORWARD;
1939                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1940                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1941                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1942                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1943                 } else {
1944                     /* if B type, reuse previous vectors and directions */
1945                     s->mv[0][0][0] = s->last_mv[0][0][0];
1946                     s->mv[0][0][1] = s->last_mv[0][0][1];
1947                     s->mv[1][0][0] = s->last_mv[1][0][0];
1948                     s->mv[1][0][1] = s->last_mv[1][0][1];
1949                 }
1950             }
1951         }
1952     }
1953 eos: // end of slice
1954     *buf += (get_bits_count(&s->gb) - 1) / 8;
1955     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1956     return 0;
1957 }
1958
1959 static int slice_decode_thread(AVCodecContext *c, void *arg)
1960 {
1961     MpegEncContext *s   = *(void **) arg;
1962     const uint8_t *buf  = s->gb.buffer;
1963     int mb_y            = s->start_mb_y;
1964     const int field_pic = s->picture_structure != PICT_FRAME;
1965
1966     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1967
1968     for (;;) {
1969         uint32_t start_code;
1970         int ret;
1971
1972         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1973         emms_c();
1974         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1975                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
1976                 s->start_mb_y, s->end_mb_y, s->er.error_count);
1977         if (ret < 0) {
1978             if (c->err_recognition & AV_EF_EXPLODE)
1979                 return ret;
1980             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1981                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
1982                                 s->mb_x, s->mb_y,
1983                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
1984         } else {
1985             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
1986                             s->mb_x - 1, s->mb_y,
1987                             ER_AC_END | ER_DC_END | ER_MV_END);
1988         }
1989
1990         if (s->mb_y == s->end_mb_y)
1991             return 0;
1992
1993         start_code = -1;
1994         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
1995         mb_y       = (start_code - SLICE_MIN_START_CODE) << field_pic;
1996         if (s->picture_structure == PICT_BOTTOM_FIELD)
1997             mb_y++;
1998         if (mb_y < 0 || mb_y >= s->end_mb_y)
1999             return AVERROR_INVALIDDATA;
2000     }
2001 }
2002
2003 /**
2004  * Handle slice ends.
2005  * @return 1 if it seems to be the last slice
2006  */
2007 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2008 {
2009     Mpeg1Context *s1  = avctx->priv_data;
2010     MpegEncContext *s = &s1->mpeg_enc_ctx;
2011
2012     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2013         return 0;
2014
2015     if (s->avctx->hwaccel) {
2016         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
2017             av_log(avctx, AV_LOG_ERROR,
2018                    "hardware accelerator failed to decode picture\n");
2019     }
2020
2021 #if FF_API_XVMC
2022 FF_DISABLE_DEPRECATION_WARNINGS
2023     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
2024         ff_xvmc_field_end(s);
2025 FF_ENABLE_DEPRECATION_WARNINGS
2026 #endif /* FF_API_XVMC */
2027
2028     /* end of slice reached */
2029     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field) {
2030         /* end of image */
2031
2032         ff_er_frame_end(&s->er);
2033
2034         ff_mpv_frame_end(s);
2035
2036         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2037             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2038             if (ret < 0)
2039                 return ret;
2040             ff_print_debug_info(s, s->current_picture_ptr);
2041         } else {
2042             if (avctx->active_thread_type & FF_THREAD_FRAME)
2043                 s->picture_number++;
2044             /* latency of 1 frame for I- and P-frames */
2045             /* XXX: use another variable than picture_number */
2046             if (s->last_picture_ptr) {
2047                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2048                 if (ret < 0)
2049                     return ret;
2050                 ff_print_debug_info(s, s->last_picture_ptr);
2051             }
2052         }
2053
2054         return 1;
2055     } else {
2056         return 0;
2057     }
2058 }
2059
2060 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2061                                  const uint8_t *buf, int buf_size)
2062 {
2063     Mpeg1Context *s1  = avctx->priv_data;
2064     MpegEncContext *s = &s1->mpeg_enc_ctx;
2065     int width, height;
2066     int i, v, j;
2067
2068     init_get_bits(&s->gb, buf, buf_size * 8);
2069
2070     width  = get_bits(&s->gb, 12);
2071     height = get_bits(&s->gb, 12);
2072     if (width == 0 || height == 0) {
2073         av_log(avctx, AV_LOG_WARNING,
2074                "Invalid horizontal or vertical size value.\n");
2075         if (avctx->err_recognition & AV_EF_BITSTREAM)
2076             return AVERROR_INVALIDDATA;
2077     }
2078     s->aspect_ratio_info = get_bits(&s->gb, 4);
2079     if (s->aspect_ratio_info == 0) {
2080         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2081         if (avctx->err_recognition & AV_EF_BITSTREAM)
2082             return AVERROR_INVALIDDATA;
2083     }
2084     s->frame_rate_index = get_bits(&s->gb, 4);
2085     if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
2086         av_log(avctx, AV_LOG_WARNING,
2087                "frame_rate_index %d is invalid\n", s->frame_rate_index);
2088         return AVERROR_INVALIDDATA;
2089     }
2090     s->bit_rate = get_bits(&s->gb, 18) * 400;
2091     if (get_bits1(&s->gb) == 0) { /* marker */
2092         av_log(avctx, AV_LOG_ERROR, "Marker in sequence header missing\n");
2093         return AVERROR_INVALIDDATA;
2094     }
2095     s->width  = width;
2096     s->height = height;
2097
2098     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2099     skip_bits(&s->gb, 1);
2100
2101     /* get matrix */
2102     if (get_bits1(&s->gb)) {
2103         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2104     } else {
2105         for (i = 0; i < 64; i++) {
2106             j = s->idsp.idct_permutation[i];
2107             v = ff_mpeg1_default_intra_matrix[i];
2108             s->intra_matrix[j]        = v;
2109             s->chroma_intra_matrix[j] = v;
2110         }
2111     }
2112     if (get_bits1(&s->gb)) {
2113         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2114     } else {
2115         for (i = 0; i < 64; i++) {
2116             int j = s->idsp.idct_permutation[i];
2117             v = ff_mpeg1_default_non_intra_matrix[i];
2118             s->inter_matrix[j]        = v;
2119             s->chroma_inter_matrix[j] = v;
2120         }
2121     }
2122
2123     if (show_bits(&s->gb, 23) != 0) {
2124         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2125         return AVERROR_INVALIDDATA;
2126     }
2127
2128     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2129     s->progressive_sequence = 1;
2130     s->progressive_frame    = 1;
2131     s->picture_structure    = PICT_FRAME;
2132     s->frame_pred_frame_dct = 1;
2133     s->chroma_format        = 1;
2134     s->codec_id             =
2135     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2136     s->out_format           = FMT_MPEG1;
2137     if (s->flags & CODEC_FLAG_LOW_DELAY)
2138         s->low_delay = 1;
2139
2140     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2141         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2142                s->avctx->rc_buffer_size, s->bit_rate);
2143
2144     return 0;
2145 }
2146
2147 static int vcr2_init_sequence(AVCodecContext *avctx)
2148 {
2149     Mpeg1Context *s1  = avctx->priv_data;
2150     MpegEncContext *s = &s1->mpeg_enc_ctx;
2151     int i, v, ret;
2152
2153     /* start new MPEG-1 context decoding */
2154     s->out_format = FMT_MPEG1;
2155     if (s1->mpeg_enc_ctx_allocated) {
2156         ff_mpv_common_end(s);
2157     }
2158     s->width            = avctx->coded_width;
2159     s->height           = avctx->coded_height;
2160     avctx->has_b_frames = 0; // true?
2161     s->low_delay        = 1;
2162
2163     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2164
2165 #if FF_API_XVMC
2166     if ((avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel) &&
2167         avctx->idct_algo == FF_IDCT_AUTO)
2168 #else
2169     if (avctx->hwaccel && avctx->idct_algo == FF_IDCT_AUTO)
2170 #endif /* FF_API_XVMC */
2171         avctx->idct_algo = FF_IDCT_SIMPLE;
2172
2173     ff_mpv_idct_init(s);
2174     if ((ret = ff_mpv_common_init(s)) < 0)
2175         return ret;
2176     s1->mpeg_enc_ctx_allocated = 1;
2177
2178     for (i = 0; i < 64; i++) {
2179         int j = s->idsp.idct_permutation[i];
2180         v = ff_mpeg1_default_intra_matrix[i];
2181         s->intra_matrix[j]        = v;
2182         s->chroma_intra_matrix[j] = v;
2183
2184         v = ff_mpeg1_default_non_intra_matrix[i];
2185         s->inter_matrix[j]        = v;
2186         s->chroma_inter_matrix[j] = v;
2187     }
2188
2189     s->progressive_sequence  = 1;
2190     s->progressive_frame     = 1;
2191     s->picture_structure     = PICT_FRAME;
2192     s->frame_pred_frame_dct  = 1;
2193     s->chroma_format         = 1;
2194     s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2195     s1->save_width           = s->width;
2196     s1->save_height          = s->height;
2197     s1->save_progressive_seq = s->progressive_sequence;
2198     return 0;
2199 }
2200
2201 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2202                               const uint8_t *p, int buf_size)
2203 {
2204     Mpeg1Context *s1 = avctx->priv_data;
2205
2206     if (buf_size >= 6 &&
2207         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2208         p[4] == 3 && (p[5] & 0x40)) {
2209         /* extract A53 Part 4 CC data */
2210         int cc_count = p[5] & 0x1f;
2211         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2212             av_freep(&s1->a53_caption);
2213             s1->a53_caption_size = cc_count * 3;
2214             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2215             if (s1->a53_caption)
2216                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2217         }
2218         return 1;
2219     } else if (buf_size >= 11 &&
2220                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2221         /* extract DVD CC data */
2222         int cc_count = 0;
2223         int i;
2224         // There is a caption count field in the data, but it is often
2225         // incorect.  So count the number of captions present.
2226         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2227             cc_count++;
2228         // Transform the DVD format into A53 Part 4 format
2229         if (cc_count > 0) {
2230             av_freep(&s1->a53_caption);
2231             s1->a53_caption_size = cc_count * 6;
2232             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2233             if (s1->a53_caption) {
2234                 uint8_t field1 = !!(p[4] & 0x80);
2235                 uint8_t *cap = s1->a53_caption;
2236                 p += 5;
2237                 for (i = 0; i < cc_count; i++) {
2238                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2239                     cap[1] = p[1];
2240                     cap[2] = p[2];
2241                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2242                     cap[4] = p[4];
2243                     cap[5] = p[5];
2244                     cap += 6;
2245                     p += 6;
2246                 }
2247             }
2248         }
2249         return 1;
2250     }
2251     return 0;
2252 }
2253
2254 static void mpeg_decode_user_data(AVCodecContext *avctx,
2255                                   const uint8_t *p, int buf_size)
2256 {
2257     const uint8_t *buf_end = p + buf_size;
2258     Mpeg1Context *s1 = avctx->priv_data;
2259
2260     /* we parse the DTG active format information */
2261     if (buf_end - p >= 5 &&
2262         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2263         int flags = p[4];
2264         p += 5;
2265         if (flags & 0x80) {
2266             /* skip event id */
2267             p += 2;
2268         }
2269         if (flags & 0x40) {
2270             if (buf_end - p < 1)
2271                 return;
2272 #if FF_API_AFD
2273 FF_DISABLE_DEPRECATION_WARNINGS
2274             avctx->dtg_active_format = p[0] & 0x0f;
2275 FF_ENABLE_DEPRECATION_WARNINGS
2276 #endif /* FF_API_AFD */
2277             s1->has_afd = 1;
2278             s1->afd     = p[0] & 0x0f;
2279         }
2280     } else if (buf_end - p >= 6 &&
2281                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2282                p[4] == 0x03) { // S3D_video_format_length
2283         // the 0x7F mask ignores the reserved_bit value
2284         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2285
2286         if (S3D_video_format_type == 0x03 ||
2287             S3D_video_format_type == 0x04 ||
2288             S3D_video_format_type == 0x08 ||
2289             S3D_video_format_type == 0x23) {
2290
2291             s1->has_stereo3d = 1;
2292
2293             switch (S3D_video_format_type) {
2294             case 0x03:
2295                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2296                 break;
2297             case 0x04:
2298                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2299                 break;
2300             case 0x08:
2301                 s1->stereo3d.type = AV_STEREO3D_2D;
2302                 break;
2303             case 0x23:
2304                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2305                 break;
2306             }
2307         }
2308     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2309         return;
2310     }
2311 }
2312
2313 static void mpeg_decode_gop(AVCodecContext *avctx,
2314                             const uint8_t *buf, int buf_size)
2315 {
2316     Mpeg1Context *s1  = avctx->priv_data;
2317     MpegEncContext *s = &s1->mpeg_enc_ctx;
2318
2319     int time_code_hours, time_code_minutes;
2320     int time_code_seconds, time_code_pictures;
2321     int broken_link;
2322
2323     init_get_bits(&s->gb, buf, buf_size * 8);
2324
2325     skip_bits1(&s->gb); /* drop_frame_flag */
2326
2327     time_code_hours   = get_bits(&s->gb, 5);
2328     time_code_minutes = get_bits(&s->gb, 6);
2329     skip_bits1(&s->gb); // marker bit
2330     time_code_seconds  = get_bits(&s->gb, 6);
2331     time_code_pictures = get_bits(&s->gb, 6);
2332
2333     s1->closed_gop = get_bits1(&s->gb);
2334     /* broken_link indicate that after editing the
2335      * reference frames of the first B-Frames after GOP I-Frame
2336      * are missing (open gop) */
2337     broken_link = get_bits1(&s->gb);
2338
2339     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2340         av_log(s->avctx, AV_LOG_DEBUG,
2341                "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2342                time_code_hours, time_code_minutes, time_code_seconds,
2343                time_code_pictures, s1->closed_gop, broken_link);
2344 }
2345
2346 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2347                          int *got_output, const uint8_t *buf, int buf_size)
2348 {
2349     Mpeg1Context *s = avctx->priv_data;
2350     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2351     const uint8_t *buf_ptr = buf;
2352     const uint8_t *buf_end = buf + buf_size;
2353     int ret, input_size;
2354     int last_code = 0, skip_frame = 0;
2355
2356     for (;;) {
2357         /* find next start code */
2358         uint32_t start_code = -1;
2359         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2360         if (start_code > 0x1ff) {
2361             if (!skip_frame) {
2362                 if (HAVE_THREADS &&
2363                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2364                     !avctx->hwaccel) {
2365                     int i;
2366
2367                     avctx->execute(avctx, slice_decode_thread,
2368                                    &s2->thread_context[0], NULL,
2369                                    s->slice_count, sizeof(void *));
2370                     for (i = 0; i < s->slice_count; i++)
2371                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2372                 }
2373
2374                 ret = slice_end(avctx, picture);
2375                 if (ret < 0)
2376                     return ret;
2377                 else if (ret) {
2378                     // FIXME: merge with the stuff in mpeg_decode_slice
2379                     if (s2->last_picture_ptr || s2->low_delay)
2380                         *got_output = 1;
2381                 }
2382             }
2383             s2->pict_type = 0;
2384             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2385         }
2386
2387         input_size = buf_end - buf_ptr;
2388
2389         if (avctx->debug & FF_DEBUG_STARTCODE)
2390             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %td left %d\n",
2391                    start_code, buf_ptr - buf, input_size);
2392
2393         /* prepare data for next start code */
2394         switch (start_code) {
2395         case SEQ_START_CODE:
2396             if (last_code == 0) {
2397                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2398                 s->sync = 1;
2399             } else {
2400                 av_log(avctx, AV_LOG_ERROR,
2401                        "ignoring SEQ_START_CODE after %X\n", last_code);
2402                 if (avctx->err_recognition & AV_EF_EXPLODE)
2403                     return AVERROR_INVALIDDATA;
2404             }
2405             break;
2406
2407         case PICTURE_START_CODE:
2408             if (s2->width <= 0 || s2->height <= 0) {
2409                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2410                        s2->width, s2->height);
2411                 return AVERROR_INVALIDDATA;
2412             }
2413
2414             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2415                 !avctx->hwaccel && s->slice_count) {
2416                 int i;
2417
2418                 avctx->execute(avctx, slice_decode_thread,
2419                                s2->thread_context, NULL,
2420                                s->slice_count, sizeof(void *));
2421                 for (i = 0; i < s->slice_count; i++)
2422                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2423                 s->slice_count = 0;
2424             }
2425             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2426                 ret = mpeg_decode_postinit(avctx);
2427                 if (ret < 0) {
2428                     av_log(avctx, AV_LOG_ERROR,
2429                            "mpeg_decode_postinit() failure\n");
2430                     return ret;
2431                 }
2432
2433                 /* We have a complete image: we try to decompress it. */
2434                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2435                     s2->pict_type = 0;
2436                 s->first_slice = 1;
2437                 last_code      = PICTURE_START_CODE;
2438             } else {
2439                 av_log(avctx, AV_LOG_ERROR,
2440                        "ignoring pic after %X\n", last_code);
2441                 if (avctx->err_recognition & AV_EF_EXPLODE)
2442                     return AVERROR_INVALIDDATA;
2443             }
2444             break;
2445         case EXT_START_CODE:
2446             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2447
2448             switch (get_bits(&s2->gb, 4)) {
2449             case 0x1:
2450                 if (last_code == 0) {
2451                     mpeg_decode_sequence_extension(s);
2452                 } else {
2453                     av_log(avctx, AV_LOG_ERROR,
2454                            "ignoring seq ext after %X\n", last_code);
2455                     if (avctx->err_recognition & AV_EF_EXPLODE)
2456                         return AVERROR_INVALIDDATA;
2457                 }
2458                 break;
2459             case 0x2:
2460                 mpeg_decode_sequence_display_extension(s);
2461                 break;
2462             case 0x3:
2463                 mpeg_decode_quant_matrix_extension(s2);
2464                 break;
2465             case 0x7:
2466                 mpeg_decode_picture_display_extension(s);
2467                 break;
2468             case 0x8:
2469                 if (last_code == PICTURE_START_CODE) {
2470                     mpeg_decode_picture_coding_extension(s);
2471                 } else {
2472                     av_log(avctx, AV_LOG_ERROR,
2473                            "ignoring pic cod ext after %X\n", last_code);
2474                     if (avctx->err_recognition & AV_EF_EXPLODE)
2475                         return AVERROR_INVALIDDATA;
2476                 }
2477                 break;
2478             }
2479             break;
2480         case USER_START_CODE:
2481             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2482             break;
2483         case GOP_START_CODE:
2484             if (last_code == 0) {
2485                 s2->first_field = 0;
2486                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2487                 s->sync = 1;
2488             } else {
2489                 av_log(avctx, AV_LOG_ERROR,
2490                        "ignoring GOP_START_CODE after %X\n", last_code);
2491                 if (avctx->err_recognition & AV_EF_EXPLODE)
2492                     return AVERROR_INVALIDDATA;
2493             }
2494             break;
2495         default:
2496             if (start_code >= SLICE_MIN_START_CODE &&
2497                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2498                 const int field_pic = s2->picture_structure != PICT_FRAME;
2499                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
2500                 last_code = SLICE_MIN_START_CODE;
2501
2502                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2503                     mb_y++;
2504
2505                 if (mb_y >= s2->mb_height) {
2506                     av_log(s2->avctx, AV_LOG_ERROR,
2507                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2508                     return AVERROR_INVALIDDATA;
2509                 }
2510
2511                 if (!s2->last_picture_ptr) {
2512                     /* Skip B-frames if we do not have reference frames and
2513                      * GOP is not closed. */
2514                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2515                         if (!s->closed_gop) {
2516                             skip_frame = 1;
2517                             break;
2518                         }
2519                     }
2520                 }
2521                 if (s2->pict_type == AV_PICTURE_TYPE_I)
2522                     s->sync = 1;
2523                 if (!s2->next_picture_ptr) {
2524                     /* Skip P-frames if we do not have a reference frame or
2525                      * we have an invalid header. */
2526                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2527                         skip_frame = 1;
2528                         break;
2529                     }
2530                 }
2531                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2532                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2533                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2534                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2535                     avctx->skip_frame >= AVDISCARD_ALL) {
2536                     skip_frame = 1;
2537                     break;
2538                 }
2539
2540                 if (!s->mpeg_enc_ctx_allocated)
2541                     break;
2542
2543                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2544                     if (mb_y < avctx->skip_top ||
2545                         mb_y >= s2->mb_height - avctx->skip_bottom)
2546                         break;
2547                 }
2548
2549                 if (!s2->pict_type) {
2550                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2551                     if (avctx->err_recognition & AV_EF_EXPLODE)
2552                         return AVERROR_INVALIDDATA;
2553                     break;
2554                 }
2555
2556                 if (s->first_slice) {
2557                     skip_frame     = 0;
2558                     s->first_slice = 0;
2559                     if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
2560                         return ret;
2561                 }
2562                 if (!s2->current_picture_ptr) {
2563                     av_log(avctx, AV_LOG_ERROR,
2564                            "current_picture not initialized\n");
2565                     return AVERROR_INVALIDDATA;
2566                 }
2567
2568                 if (HAVE_THREADS &&
2569                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2570                     !avctx->hwaccel) {
2571                     int threshold = (s2->mb_height * s->slice_count +
2572                                      s2->slice_context_count / 2) /
2573                                     s2->slice_context_count;
2574                     if (threshold <= mb_y) {
2575                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2576
2577                         thread_context->start_mb_y = mb_y;
2578                         thread_context->end_mb_y   = s2->mb_height;
2579                         if (s->slice_count) {
2580                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2581                             ret = ff_update_duplicate_context(thread_context, s2);
2582                             if (ret < 0)
2583                                 return ret;
2584                         }
2585                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2586                         s->slice_count++;
2587                     }
2588                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2589                 } else {
2590                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2591                     emms_c();
2592
2593                     if (ret < 0) {
2594                         if (avctx->err_recognition & AV_EF_EXPLODE)
2595                             return ret;
2596                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2597                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2598                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2599                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2600                     } else {
2601                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2602                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2603                                         ER_AC_END | ER_DC_END | ER_MV_END);
2604                     }
2605                 }
2606             }
2607             break;
2608         }
2609     }
2610 }
2611
2612 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2613                              int *got_output, AVPacket *avpkt)
2614 {
2615     const uint8_t *buf = avpkt->data;
2616     int buf_size = avpkt->size;
2617     Mpeg1Context *s = avctx->priv_data;
2618     AVFrame *picture = data;
2619     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2620     av_dlog(avctx, "fill_buffer\n");
2621
2622     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2623         /* special case for last picture */
2624         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2625             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2626             if (ret < 0)
2627                 return ret;
2628
2629             s2->next_picture_ptr = NULL;
2630
2631             *got_output = 1;
2632         }
2633         return buf_size;
2634     }
2635
2636     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2637         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2638                                            buf_size, NULL);
2639
2640         if (ff_combine_frame(&s2->parse_context, next,
2641                              (const uint8_t **) &buf, &buf_size) < 0)
2642             return buf_size;
2643     }
2644
2645     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
2646         vcr2_init_sequence(avctx);
2647
2648     s->slice_count = 0;
2649
2650     if (avctx->extradata && !s->extradata_decoded) {
2651         int ret = decode_chunks(avctx, picture, got_output,
2652                                 avctx->extradata, avctx->extradata_size);
2653         s->extradata_decoded = 1;
2654         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2655             return ret;
2656     }
2657
2658     return decode_chunks(avctx, picture, got_output, buf, buf_size);
2659 }
2660
2661 static void flush(AVCodecContext *avctx)
2662 {
2663     Mpeg1Context *s = avctx->priv_data;
2664
2665     s->sync       = 0;
2666     s->closed_gop = 0;
2667
2668     ff_mpeg_flush(avctx);
2669 }
2670
2671 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2672 {
2673     Mpeg1Context *s = avctx->priv_data;
2674
2675     if (s->mpeg_enc_ctx_allocated)
2676         ff_mpv_common_end(&s->mpeg_enc_ctx);
2677     av_freep(&s->a53_caption);
2678     return 0;
2679 }
2680
2681 static const AVProfile mpeg2_video_profiles[] = {
2682     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2683     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2684     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2685     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2686     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2687     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2688     { FF_PROFILE_RESERVED,           "Reserved"           },
2689     { FF_PROFILE_RESERVED,           "Reserved"           },
2690     { FF_PROFILE_UNKNOWN                                  },
2691 };
2692
2693 AVCodec ff_mpeg1video_decoder = {
2694     .name                  = "mpeg1video",
2695     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
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_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2703                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2704                              CODEC_CAP_SLICE_THREADS,
2705     .flush                 = flush,
2706     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2707 };
2708
2709 AVCodec ff_mpeg2video_decoder = {
2710     .name           = "mpeg2video",
2711     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2712     .type           = AVMEDIA_TYPE_VIDEO,
2713     .id             = AV_CODEC_ID_MPEG2VIDEO,
2714     .priv_data_size = sizeof(Mpeg1Context),
2715     .init           = mpeg_decode_init,
2716     .close          = mpeg_decode_end,
2717     .decode         = mpeg_decode_frame,
2718     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2719                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2720                       CODEC_CAP_SLICE_THREADS,
2721     .flush          = flush,
2722     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2723 };
2724
2725 #if FF_API_XVMC
2726 #if CONFIG_MPEG_XVMC_DECODER
2727 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2728 {
2729     if (avctx->active_thread_type & FF_THREAD_SLICE)
2730         return -1;
2731     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2732         return -1;
2733     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2734         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2735     }
2736     mpeg_decode_init(avctx);
2737
2738     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2739     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2740
2741     return 0;
2742 }
2743
2744 AVCodec ff_mpeg_xvmc_decoder = {
2745     .name           = "mpegvideo_xvmc",
2746     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2747     .type           = AVMEDIA_TYPE_VIDEO,
2748     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2749     .priv_data_size = sizeof(Mpeg1Context),
2750     .init           = mpeg_mc_decode_init,
2751     .close          = mpeg_decode_end,
2752     .decode         = mpeg_decode_frame,
2753     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2754                       CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2755     .flush          = flush,
2756 };
2757
2758 #endif
2759 #endif /* FF_API_XVMC */