16c85231122b3b829110f832ea6554213bcd4359
[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 //#define DEBUG
29 #include "libavutil/attributes.h"
30 #include "libavutil/internal.h"
31 #include "internal.h"
32 #include "avcodec.h"
33 #include "dsputil.h"
34 #include "mpegvideo.h"
35 #include "error_resilience.h"
36 #include "mpeg12.h"
37 #include "mpeg12data.h"
38 #include "mpeg12decdata.h"
39 #include "bytestream.h"
40 #include "vdpau_internal.h"
41 #include "xvmc_internal.h"
42 #include "thread.h"
43
44 //#undef NDEBUG
45 //#include <assert.h>
46
47 typedef struct Mpeg1Context {
48     MpegEncContext mpeg_enc_ctx;
49     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
50     int repeat_field; /* true if we must repeat the field */
51     AVPanScan pan_scan;              /**< some temporary storage for the panscan */
52     int slice_count;
53     int swap_uv;//indicate VCR2
54     int save_aspect_info;
55     int save_width, save_height, save_progressive_seq;
56     AVRational frame_rate_ext;       ///< MPEG-2 specific framerate modificator
57     int sync;                        ///< Did we reach a sync point like a GOP/SEQ/KEYFrame?
58     int closed_gop;                  ///< GOP is closed
59     int extradata_decoded;
60 } Mpeg1Context;
61
62 /* as H.263, but only 17 codes */
63 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
64 {
65     int code, sign, val, shift;
66
67     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
68     if (code == 0) {
69         return pred;
70     }
71     if (code < 0) {
72         return 0xffff;
73     }
74
75     sign  = get_bits1(&s->gb);
76     shift = fcode - 1;
77     val   = code;
78     if (shift) {
79         val  = (val - 1) << shift;
80         val |= get_bits(&s->gb, shift);
81         val++;
82     }
83     if (sign)
84         val = -val;
85     val += pred;
86
87     /* modulo decoding */
88     return sign_extend(val, 5 + shift);
89 }
90
91 static inline int mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
92 {
93     int level, dc, diff, i, j, run;
94     int component;
95     RLTable *rl = &ff_rl_mpeg1;
96     uint8_t * const scantable    = s->intra_scantable.permutated;
97     const uint16_t *quant_matrix = s->intra_matrix;
98     const int qscale             = s->qscale;
99
100     /* DC coefficient */
101     component = (n <= 3 ? 0 : n - 4 + 1);
102     diff = decode_dc(&s->gb, component);
103     if (diff >= 0xffff)
104         return -1;
105     dc  = s->last_dc[component];
106     dc += diff;
107     s->last_dc[component] = dc;
108     block[0] = dc * quant_matrix[0];
109     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
110     i = 0;
111     {
112         OPEN_READER(re, &s->gb);
113         /* now quantify & encode AC coefficients */
114         for (;;) {
115             UPDATE_CACHE(re, &s->gb);
116             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
117
118             if (level == 127) {
119                 break;
120             } else if (level != 0) {
121                 i += run;
122                 j = scantable[i];
123                 level = (level * qscale * quant_matrix[j]) >> 4;
124                 level = (level - 1) | 1;
125                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
126                 LAST_SKIP_BITS(re, &s->gb, 1);
127             } else {
128                 /* escape */
129                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
130                 UPDATE_CACHE(re, &s->gb);
131                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
132                 if (level == -128) {
133                     level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
134                 } else if (level == 0) {
135                     level = SHOW_UBITS(re, &s->gb, 8)      ; LAST_SKIP_BITS(re, &s->gb, 8);
136                 }
137                 i += run;
138                 j = scantable[i];
139                 if (level < 0) {
140                     level = -level;
141                     level = (level * qscale * quant_matrix[j]) >> 4;
142                     level = (level - 1) | 1;
143                     level = -level;
144                 } else {
145                     level = (level * qscale * quant_matrix[j]) >> 4;
146                     level = (level - 1) | 1;
147                 }
148             }
149             if (i > 63) {
150                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
151                 return -1;
152             }
153
154             block[j] = level;
155         }
156         CLOSE_READER(re, &s->gb);
157     }
158     s->block_last_index[n] = i;
159    return 0;
160 }
161
162 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
163 {
164     return mpeg1_decode_block_intra(s, block, n);
165 }
166
167 static inline int mpeg1_decode_block_inter(MpegEncContext *s, int16_t *block, int n)
168 {
169     int level, i, j, run;
170     RLTable *rl = &ff_rl_mpeg1;
171     uint8_t * const scantable    = s->intra_scantable.permutated;
172     const uint16_t *quant_matrix = s->inter_matrix;
173     const int qscale             = s->qscale;
174
175     {
176         OPEN_READER(re, &s->gb);
177         i = -1;
178         // special case for first coefficient, no need to add second VLC table
179         UPDATE_CACHE(re, &s->gb);
180         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
181             level = (3 * qscale * quant_matrix[0]) >> 5;
182             level = (level - 1) | 1;
183             if (GET_CACHE(re, &s->gb) & 0x40000000)
184                 level = -level;
185             block[0] = level;
186             i++;
187             SKIP_BITS(re, &s->gb, 2);
188             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
189                 goto end;
190         }
191         /* now quantify & encode AC coefficients */
192         for (;;) {
193             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
194
195             if (level != 0) {
196                 i += run;
197                 j = scantable[i];
198                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
199                 level = (level - 1) | 1;
200                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
201                 SKIP_BITS(re, &s->gb, 1);
202             } else {
203                 /* escape */
204                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
205                 UPDATE_CACHE(re, &s->gb);
206                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
207                 if (level == -128) {
208                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
209                 } else if (level == 0) {
210                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
211                 }
212                 i += run;
213                 j = scantable[i];
214                 if (level < 0) {
215                     level = -level;
216                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
217                     level = (level - 1) | 1;
218                     level = -level;
219                 } else {
220                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
221                     level = (level - 1) | 1;
222                 }
223             }
224             if (i > 63) {
225                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
226                 return -1;
227             }
228
229             block[j] = level;
230             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
231                 break;
232             UPDATE_CACHE(re, &s->gb);
233         }
234 end:
235         LAST_SKIP_BITS(re, &s->gb, 2);
236         CLOSE_READER(re, &s->gb);
237     }
238     s->block_last_index[n] = i;
239     return 0;
240 }
241
242 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, int16_t *block, int n)
243 {
244     int level, i, j, run;
245     RLTable *rl = &ff_rl_mpeg1;
246     uint8_t * const scantable = s->intra_scantable.permutated;
247     const int qscale          = s->qscale;
248
249     {
250         OPEN_READER(re, &s->gb);
251         i = -1;
252         // special case for first coefficient, no need to add second VLC table
253         UPDATE_CACHE(re, &s->gb);
254         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
255             level = (3 * qscale) >> 1;
256             level = (level - 1) | 1;
257             if (GET_CACHE(re, &s->gb) & 0x40000000)
258                 level = -level;
259             block[0] = level;
260             i++;
261             SKIP_BITS(re, &s->gb, 2);
262             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
263                 goto end;
264         }
265
266         /* now quantify & encode AC coefficients */
267         for (;;) {
268             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
269
270             if (level != 0) {
271                 i += run;
272                 j = scantable[i];
273                 level = ((level * 2 + 1) * qscale) >> 1;
274                 level = (level - 1) | 1;
275                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
276                 SKIP_BITS(re, &s->gb, 1);
277             } else {
278                 /* escape */
279                 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
280                 UPDATE_CACHE(re, &s->gb);
281                 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
282                 if (level == -128) {
283                     level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
284                 } else if (level == 0) {
285                     level = SHOW_UBITS(re, &s->gb, 8)      ; SKIP_BITS(re, &s->gb, 8);
286                 }
287                 i += run;
288                 j = scantable[i];
289                 if (level < 0) {
290                     level = -level;
291                     level = ((level * 2 + 1) * qscale) >> 1;
292                     level = (level - 1) | 1;
293                     level = -level;
294                 } else {
295                     level = ((level * 2 + 1) * qscale) >> 1;
296                     level = (level - 1) | 1;
297                 }
298             }
299
300             block[j] = level;
301             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
302                 break;
303             UPDATE_CACHE(re, &s->gb);
304         }
305 end:
306         LAST_SKIP_BITS(re, &s->gb, 2);
307         CLOSE_READER(re, &s->gb);
308     }
309     s->block_last_index[n] = i;
310     return 0;
311 }
312
313
314 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s, int16_t *block, int n)
315 {
316     int level, i, j, run;
317     RLTable *rl = &ff_rl_mpeg1;
318     uint8_t * const scantable = s->intra_scantable.permutated;
319     const uint16_t *quant_matrix;
320     const int qscale = s->qscale;
321     int mismatch;
322
323     mismatch = 1;
324
325     {
326         OPEN_READER(re, &s->gb);
327         i = -1;
328         if (n < 4)
329             quant_matrix = s->inter_matrix;
330         else
331             quant_matrix = s->chroma_inter_matrix;
332
333         // special case for first coefficient, no need to add second VLC table
334         UPDATE_CACHE(re, &s->gb);
335         if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
336             level= (3 * qscale * quant_matrix[0]) >> 5;
337             if (GET_CACHE(re, &s->gb) & 0x40000000)
338                 level = -level;
339             block[0]  = level;
340             mismatch ^= level;
341             i++;
342             SKIP_BITS(re, &s->gb, 2);
343             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
344                 goto end;
345         }
346
347         /* now quantify & encode AC coefficients */
348         for (;;) {
349             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
350
351             if (level != 0) {
352                 i += run;
353                 j = scantable[i];
354                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
355                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
356                 SKIP_BITS(re, &s->gb, 1);
357             } else {
358                 /* escape */
359                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
360                 UPDATE_CACHE(re, &s->gb);
361                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
362
363                 i += run;
364                 j = scantable[i];
365                 if (level < 0) {
366                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
367                     level = -level;
368                 } else {
369                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
370                 }
371             }
372             if (i > 63) {
373                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
374                 return -1;
375             }
376
377             mismatch ^= level;
378             block[j]  = level;
379             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
380                 break;
381             UPDATE_CACHE(re, &s->gb);
382         }
383 end:
384         LAST_SKIP_BITS(re, &s->gb, 2);
385         CLOSE_READER(re, &s->gb);
386     }
387     block[63] ^= (mismatch & 1);
388
389     s->block_last_index[n] = i;
390     return 0;
391 }
392
393 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
394                                                     int16_t *block, int n)
395 {
396     int level, i, j, run;
397     RLTable *rl = &ff_rl_mpeg1;
398     uint8_t * const scantable = s->intra_scantable.permutated;
399     const int qscale          = s->qscale;
400     OPEN_READER(re, &s->gb);
401     i = -1;
402
403     // special case for first coefficient, no need to add second VLC table
404     UPDATE_CACHE(re, &s->gb);
405     if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
406         level = (3 * qscale) >> 1;
407         if (GET_CACHE(re, &s->gb) & 0x40000000)
408             level = -level;
409         block[0] = level;
410         i++;
411         SKIP_BITS(re, &s->gb, 2);
412         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
413             goto end;
414     }
415
416     /* now quantify & encode AC coefficients */
417     for (;;) {
418         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
419
420         if (level != 0) {
421             i += run;
422             j  = scantable[i];
423             level = ((level * 2 + 1) * qscale) >> 1;
424             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - 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; LAST_SKIP_BITS(re, &s->gb, 6);
429             UPDATE_CACHE(re, &s->gb);
430             level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
431
432             i += run;
433             j  = scantable[i];
434             if (level < 0) {
435                 level = ((-level * 2 + 1) * qscale) >> 1;
436                 level = -level;
437             } else {
438                 level = ((level * 2 + 1) * qscale) >> 1;
439             }
440         }
441
442         block[j] = level;
443         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
444             break;
445         UPDATE_CACHE(re, &s->gb);
446     }
447 end:
448     LAST_SKIP_BITS(re, &s->gb, 2);
449     CLOSE_READER(re, &s->gb);
450     s->block_last_index[n] = i;
451     return 0;
452 }
453
454
455 static inline int mpeg2_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
456 {
457     int level, dc, diff, i, j, run;
458     int component;
459     RLTable *rl;
460     uint8_t * const scantable = s->intra_scantable.permutated;
461     const uint16_t *quant_matrix;
462     const int qscale = s->qscale;
463     int mismatch;
464
465     /* DC coefficient */
466     if (n < 4) {
467         quant_matrix = s->intra_matrix;
468         component = 0;
469     } else {
470         quant_matrix = s->chroma_intra_matrix;
471         component = (n & 1) + 1;
472     }
473     diff = decode_dc(&s->gb, component);
474     if (diff >= 0xffff)
475         return -1;
476     dc  = s->last_dc[component];
477     dc += diff;
478     s->last_dc[component] = dc;
479     block[0] = dc << (3 - s->intra_dc_precision);
480     av_dlog(s->avctx, "dc=%d\n", block[0]);
481     mismatch = block[0] ^ 1;
482     i = 0;
483     if (s->intra_vlc_format)
484         rl = &ff_rl_mpeg2;
485     else
486         rl = &ff_rl_mpeg1;
487
488     {
489         OPEN_READER(re, &s->gb);
490         /* now quantify & encode AC coefficients */
491         for (;;) {
492             UPDATE_CACHE(re, &s->gb);
493             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
494
495             if (level == 127) {
496                 break;
497             } else if (level != 0) {
498                 i += run;
499                 j  = scantable[i];
500                 level = (level * qscale * quant_matrix[j]) >> 4;
501                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
502                 LAST_SKIP_BITS(re, &s->gb, 1);
503             } else {
504                 /* escape */
505                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
506                 UPDATE_CACHE(re, &s->gb);
507                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
508                 i += run;
509                 j  = scantable[i];
510                 if (level < 0) {
511                     level = (-level * qscale * quant_matrix[j]) >> 4;
512                     level = -level;
513                 } else {
514                     level = (level * qscale * quant_matrix[j]) >> 4;
515                 }
516             }
517             if (i > 63) {
518                 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
519                 return -1;
520             }
521
522             mismatch ^= level;
523             block[j]  = level;
524         }
525         CLOSE_READER(re, &s->gb);
526     }
527     block[63] ^= mismatch & 1;
528
529     s->block_last_index[n] = i;
530     return 0;
531 }
532
533 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
534 {
535     int level, dc, diff, j, run;
536     int component;
537     RLTable *rl;
538     uint8_t * scantable = s->intra_scantable.permutated;
539     const uint16_t *quant_matrix;
540     const int qscale = s->qscale;
541
542     /* DC coefficient */
543     if (n < 4) {
544         quant_matrix = s->intra_matrix;
545         component = 0;
546     } else {
547         quant_matrix = s->chroma_intra_matrix;
548         component = (n & 1) + 1;
549     }
550     diff = decode_dc(&s->gb, component);
551     if (diff >= 0xffff)
552         return -1;
553     dc = s->last_dc[component];
554     dc += diff;
555     s->last_dc[component] = dc;
556     block[0] = dc << (3 - s->intra_dc_precision);
557     if (s->intra_vlc_format)
558         rl = &ff_rl_mpeg2;
559     else
560         rl = &ff_rl_mpeg1;
561
562     {
563         OPEN_READER(re, &s->gb);
564         /* now quantify & encode AC coefficients */
565         for (;;) {
566             UPDATE_CACHE(re, &s->gb);
567             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
568
569             if (level == 127) {
570                 break;
571             } else if (level != 0) {
572                 scantable += run;
573                 j = *scantable;
574                 level = (level * qscale * quant_matrix[j]) >> 4;
575                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
576                 LAST_SKIP_BITS(re, &s->gb, 1);
577             } else {
578                 /* escape */
579                 run = SHOW_UBITS(re, &s->gb, 6) + 1; LAST_SKIP_BITS(re, &s->gb, 6);
580                 UPDATE_CACHE(re, &s->gb);
581                 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
582                 scantable += run;
583                 j = *scantable;
584                 if (level < 0) {
585                     level = (-level * qscale * quant_matrix[j]) >> 4;
586                     level = -level;
587                 } else {
588                     level = (level * qscale * quant_matrix[j]) >> 4;
589                 }
590             }
591
592             block[j] = level;
593         }
594         CLOSE_READER(re, &s->gb);
595     }
596
597     s->block_last_index[n] = scantable - s->intra_scantable.permutated;
598     return 0;
599 }
600
601 /******************************************/
602 /* decoding */
603
604 static inline int get_dmv(MpegEncContext *s)
605 {
606     if (get_bits1(&s->gb))
607         return 1 - (get_bits1(&s->gb) << 1);
608     else
609         return 0;
610 }
611
612 static inline int get_qscale(MpegEncContext *s)
613 {
614     int qscale = get_bits(&s->gb, 5);
615     if (s->q_scale_type) {
616         return non_linear_qscale[qscale];
617     } else {
618         return qscale << 1;
619     }
620 }
621
622 static void exchange_uv(MpegEncContext *s)
623 {
624     int16_t (*tmp)[64];
625
626     tmp           = s->pblocks[4];
627     s->pblocks[4] = s->pblocks[5];
628     s->pblocks[5] = tmp;
629 }
630
631 /* motion type (for MPEG-2) */
632 #define MT_FIELD 1
633 #define MT_FRAME 2
634 #define MT_16X8  2
635 #define MT_DMV   3
636
637 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
638 {
639     int i, j, k, cbp, val, mb_type, motion_type;
640     const int mb_block_count = 4 + (1 << s->chroma_format);
641
642     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
643
644     assert(s->mb_skipped == 0);
645
646     if (s->mb_skip_run-- != 0) {
647         if (s->pict_type == AV_PICTURE_TYPE_P) {
648             s->mb_skipped = 1;
649             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
650         } else {
651             int mb_type;
652
653             if (s->mb_x)
654                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
655             else
656                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1]; // FIXME not sure if this is allowed in MPEG at all
657             if (IS_INTRA(mb_type))
658                 return -1;
659             s->current_picture.mb_type[s->mb_x + s->mb_y*s->mb_stride] =
660                 mb_type | MB_TYPE_SKIP;
661 //            assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
662
663             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
664                 s->mb_skipped = 1;
665         }
666
667         return 0;
668     }
669
670     switch (s->pict_type) {
671     default:
672     case AV_PICTURE_TYPE_I:
673         if (get_bits1(&s->gb) == 0) {
674             if (get_bits1(&s->gb) == 0) {
675                 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
676                 return -1;
677             }
678             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
679         } else {
680             mb_type = MB_TYPE_INTRA;
681         }
682         break;
683     case AV_PICTURE_TYPE_P:
684         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
685         if (mb_type < 0) {
686             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
687             return -1;
688         }
689         mb_type = ptype2mb_type[mb_type];
690         break;
691     case AV_PICTURE_TYPE_B:
692         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
693         if (mb_type < 0) {
694             av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
695             return -1;
696         }
697         mb_type = btype2mb_type[mb_type];
698         break;
699     }
700     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
701 //    motion_type = 0; /* avoid warning */
702     if (IS_INTRA(mb_type)) {
703         s->dsp.clear_blocks(s->block[0]);
704
705         if (!s->chroma_y_shift) {
706             s->dsp.clear_blocks(s->block[6]);
707         }
708
709         /* compute DCT type */
710         if (s->picture_structure == PICT_FRAME && // FIXME add an interlaced_dct coded var?
711             !s->frame_pred_frame_dct) {
712             s->interlaced_dct = get_bits1(&s->gb);
713         }
714
715         if (IS_QUANT(mb_type))
716             s->qscale = get_qscale(s);
717
718         if (s->concealment_motion_vectors) {
719             /* just parse them */
720             if (s->picture_structure != PICT_FRAME)
721                 skip_bits1(&s->gb); /* field select */
722
723             s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
724                 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
725             s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
726                 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
727
728             skip_bits1(&s->gb); /* marker */
729         } else
730             memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
731         s->mb_intra = 1;
732         // if 1, we memcpy blocks in xvmcvideo
733         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
734             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
735             if (s->swap_uv) {
736                 exchange_uv(s);
737             }
738         }
739
740         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
741             if (s->flags2 & CODEC_FLAG2_FAST) {
742                 for (i = 0; i < 6; i++) {
743                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
744                 }
745             } else {
746                 for (i = 0; i < mb_block_count; i++) {
747                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
748                         return -1;
749                 }
750             }
751         } else {
752             for (i = 0; i < 6; i++) {
753                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
754                     return -1;
755             }
756         }
757     } else {
758         if (mb_type & MB_TYPE_ZERO_MV) {
759             assert(mb_type & MB_TYPE_CBP);
760
761             s->mv_dir = MV_DIR_FORWARD;
762             if (s->picture_structure == PICT_FRAME) {
763                 if (!s->frame_pred_frame_dct)
764                     s->interlaced_dct = get_bits1(&s->gb);
765                 s->mv_type = MV_TYPE_16X16;
766             } else {
767                 s->mv_type = MV_TYPE_FIELD;
768                 mb_type |= MB_TYPE_INTERLACED;
769                 s->field_select[0][0] = s->picture_structure - 1;
770             }
771
772             if (IS_QUANT(mb_type))
773                 s->qscale = get_qscale(s);
774
775             s->last_mv[0][0][0] = 0;
776             s->last_mv[0][0][1] = 0;
777             s->last_mv[0][1][0] = 0;
778             s->last_mv[0][1][1] = 0;
779             s->mv[0][0][0] = 0;
780             s->mv[0][0][1] = 0;
781         } else {
782             assert(mb_type & MB_TYPE_L0L1);
783             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
784             /* get additional motion vector type */
785             if (s->frame_pred_frame_dct)
786                 motion_type = MT_FRAME;
787             else {
788                 motion_type = get_bits(&s->gb, 2);
789                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
790                     s->interlaced_dct = get_bits1(&s->gb);
791             }
792
793             if (IS_QUANT(mb_type))
794                 s->qscale = get_qscale(s);
795
796             /* motion vectors */
797             s->mv_dir = (mb_type >> 13) & 3;
798             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
799             switch (motion_type) {
800             case MT_FRAME: /* or MT_16X8 */
801                 if (s->picture_structure == PICT_FRAME) {
802                     mb_type |= MB_TYPE_16x16;
803                     s->mv_type = MV_TYPE_16X16;
804                     for (i = 0; i < 2; i++) {
805                         if (USES_LIST(mb_type, i)) {
806                             /* MT_FRAME */
807                             s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
808                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
809                             s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
810                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
811                             /* full_pel: only for MPEG-1 */
812                             if (s->full_pel[i]) {
813                                 s->mv[i][0][0] <<= 1;
814                                 s->mv[i][0][1] <<= 1;
815                             }
816                         }
817                     }
818                 } else {
819                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
820                     s->mv_type = MV_TYPE_16X8;
821                     for (i = 0; i < 2; i++) {
822                         if (USES_LIST(mb_type, i)) {
823                             /* MT_16X8 */
824                             for (j = 0; j < 2; j++) {
825                                 s->field_select[i][j] = get_bits1(&s->gb);
826                                 for (k = 0; k < 2; k++) {
827                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
828                                                              s->last_mv[i][j][k]);
829                                     s->last_mv[i][j][k] = val;
830                                     s->mv[i][j][k]      = val;
831                                 }
832                             }
833                         }
834                     }
835                 }
836                 break;
837             case MT_FIELD:
838                 s->mv_type = MV_TYPE_FIELD;
839                 if (s->picture_structure == PICT_FRAME) {
840                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
841                     for (i = 0; i < 2; i++) {
842                         if (USES_LIST(mb_type, i)) {
843                             for (j = 0; j < 2; j++) {
844                                 s->field_select[i][j] = get_bits1(&s->gb);
845                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
846                                                          s->last_mv[i][j][0]);
847                                 s->last_mv[i][j][0] = val;
848                                 s->mv[i][j][0]      = val;
849                                 av_dlog(s->avctx, "fmx=%d\n", val);
850                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
851                                                          s->last_mv[i][j][1] >> 1);
852                                 s->last_mv[i][j][1] = val << 1;
853                                 s->mv[i][j][1]      = val;
854                                 av_dlog(s->avctx, "fmy=%d\n", val);
855                             }
856                         }
857                     }
858                 } else {
859                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
860                     for (i = 0; i < 2; i++) {
861                         if (USES_LIST(mb_type, i)) {
862                             s->field_select[i][0] = get_bits1(&s->gb);
863                             for (k = 0; k < 2; k++) {
864                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
865                                                          s->last_mv[i][0][k]);
866                                 s->last_mv[i][0][k] = val;
867                                 s->last_mv[i][1][k] = val;
868                                 s->mv[i][0][k]      = val;
869                             }
870                         }
871                     }
872                 }
873                 break;
874             case MT_DMV:
875                 s->mv_type = MV_TYPE_DMV;
876                 for (i = 0; i < 2; i++) {
877                     if (USES_LIST(mb_type, i)) {
878                         int dmx, dmy, mx, my, m;
879                         const int my_shift = s->picture_structure == PICT_FRAME;
880
881                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
882                                                 s->last_mv[i][0][0]);
883                         s->last_mv[i][0][0] = mx;
884                         s->last_mv[i][1][0] = mx;
885                         dmx = get_dmv(s);
886                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
887                                                  s->last_mv[i][0][1] >> my_shift);
888                         dmy = get_dmv(s);
889
890
891                         s->last_mv[i][0][1] = my << my_shift;
892                         s->last_mv[i][1][1] = my << my_shift;
893
894                         s->mv[i][0][0] = mx;
895                         s->mv[i][0][1] = my;
896                         s->mv[i][1][0] = mx; // not used
897                         s->mv[i][1][1] = my; // not used
898
899                         if (s->picture_structure == PICT_FRAME) {
900                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
901
902                             // m = 1 + 2 * s->top_field_first;
903                             m = s->top_field_first ? 1 : 3;
904
905                             /* top -> top pred */
906                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
907                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
908                             m = 4 - m;
909                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
910                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
911                         } else {
912                             mb_type |= MB_TYPE_16x16;
913
914                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
915                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
916                             if (s->picture_structure == PICT_TOP_FIELD)
917                                 s->mv[i][2][1]--;
918                             else
919                                 s->mv[i][2][1]++;
920                         }
921                     }
922                 }
923                 break;
924             default:
925                 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
926                 return -1;
927             }
928         }
929
930         s->mb_intra = 0;
931         if (HAS_CBP(mb_type)) {
932             s->dsp.clear_blocks(s->block[0]);
933
934             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
935             if (mb_block_count > 6) {
936                  cbp <<= mb_block_count - 6;
937                  cbp  |= get_bits(&s->gb, mb_block_count - 6);
938                  s->dsp.clear_blocks(s->block[6]);
939             }
940             if (cbp <= 0) {
941                 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
942                 return -1;
943             }
944
945             //if 1, we memcpy blocks in xvmcvideo
946             if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1) {
947                 ff_xvmc_pack_pblocks(s, cbp);
948                 if (s->swap_uv) {
949                     exchange_uv(s);
950                 }
951             }
952
953             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
954                 if (s->flags2 & CODEC_FLAG2_FAST) {
955                     for (i = 0; i < 6; i++) {
956                         if (cbp & 32) {
957                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
958                         } else {
959                             s->block_last_index[i] = -1;
960                         }
961                         cbp += cbp;
962                     }
963                 } else {
964                     cbp <<= 12-mb_block_count;
965
966                     for (i = 0; i < mb_block_count; i++) {
967                         if (cbp & (1 << 11)) {
968                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
969                                 return -1;
970                         } else {
971                             s->block_last_index[i] = -1;
972                         }
973                         cbp += cbp;
974                     }
975                 }
976             } else {
977                 if (s->flags2 & CODEC_FLAG2_FAST) {
978                     for (i = 0; i < 6; i++) {
979                         if (cbp & 32) {
980                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
981                         } else {
982                             s->block_last_index[i] = -1;
983                         }
984                         cbp += cbp;
985                     }
986                 } else {
987                     for (i = 0; i < 6; i++) {
988                         if (cbp & 32) {
989                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
990                                 return -1;
991                         } else {
992                             s->block_last_index[i] = -1;
993                         }
994                         cbp += cbp;
995                     }
996                 }
997             }
998         } else {
999             for (i = 0; i < 12; i++)
1000                 s->block_last_index[i] = -1;
1001         }
1002     }
1003
1004     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1005
1006     return 0;
1007 }
1008
1009 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1010 {
1011     Mpeg1Context *s = avctx->priv_data;
1012     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1013     int i;
1014
1015     /* we need some permutation to store matrices,
1016      * until MPV_common_init() sets the real permutation. */
1017     for (i = 0; i < 64; i++)
1018        s2->dsp.idct_permutation[i]=i;
1019
1020     ff_MPV_decode_defaults(s2);
1021
1022     s->mpeg_enc_ctx.avctx  = avctx;
1023     s->mpeg_enc_ctx.flags  = avctx->flags;
1024     s->mpeg_enc_ctx.flags2 = avctx->flags2;
1025     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1026     ff_mpeg12_init_vlcs();
1027
1028     s->mpeg_enc_ctx_allocated      = 0;
1029     s->mpeg_enc_ctx.picture_number = 0;
1030     s->repeat_field                = 0;
1031     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1032     avctx->color_range = AVCOL_RANGE_MPEG;
1033     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1034         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1035     else
1036         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1037     return 0;
1038 }
1039
1040 static int mpeg_decode_update_thread_context(AVCodecContext *avctx, const AVCodecContext *avctx_from)
1041 {
1042     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1043     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1044     int err;
1045
1046     if (avctx == avctx_from || !ctx_from->mpeg_enc_ctx_allocated || !s1->context_initialized)
1047         return 0;
1048
1049     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1050     if (err) return err;
1051
1052     if (!ctx->mpeg_enc_ctx_allocated)
1053         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1054
1055     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1056         s->picture_number++;
1057
1058     return 0;
1059 }
1060
1061 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1062                                  const uint8_t *new_perm)
1063 {
1064     uint16_t temp_matrix[64];
1065     int i;
1066
1067     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1068
1069     for (i = 0; i < 64; i++) {
1070         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1071     }
1072 }
1073
1074 static const enum AVPixelFormat pixfmt_xvmc_mpg2_420[] = {
1075     AV_PIX_FMT_XVMC_MPEG2_IDCT,
1076     AV_PIX_FMT_XVMC_MPEG2_MC,
1077     AV_PIX_FMT_NONE };
1078
1079 static const enum AVPixelFormat mpeg12_hwaccel_pixfmt_list_420[] = {
1080 #if CONFIG_MPEG2_DXVA2_HWACCEL
1081     AV_PIX_FMT_DXVA2_VLD,
1082 #endif
1083 #if CONFIG_MPEG2_VAAPI_HWACCEL
1084     AV_PIX_FMT_VAAPI_VLD,
1085 #endif
1086 #if CONFIG_MPEG1_VDPAU_HWACCEL | CONFIG_MPEG2_VDPAU_HWACCEL
1087     AV_PIX_FMT_VDPAU,
1088 #endif
1089     AV_PIX_FMT_YUV420P,
1090     AV_PIX_FMT_NONE
1091 };
1092
1093 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1094 {
1095     Mpeg1Context *s1 = avctx->priv_data;
1096     MpegEncContext *s = &s1->mpeg_enc_ctx;
1097
1098     if (avctx->xvmc_acceleration)
1099         return avctx->get_format(avctx, pixfmt_xvmc_mpg2_420);
1100     else if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
1101         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO)
1102             return AV_PIX_FMT_VDPAU_MPEG1;
1103         else
1104             return AV_PIX_FMT_VDPAU_MPEG2;
1105     } else {
1106         if (s->chroma_format <  2)
1107             return avctx->get_format(avctx, mpeg12_hwaccel_pixfmt_list_420);
1108         else if (s->chroma_format == 2)
1109             return AV_PIX_FMT_YUV422P;
1110         else
1111             return AV_PIX_FMT_YUV444P;
1112     }
1113 }
1114
1115 /* Call this function when we know all parameters.
1116  * It may be called in different places for MPEG-1 and MPEG-2. */
1117 static int mpeg_decode_postinit(AVCodecContext *avctx)
1118 {
1119     Mpeg1Context *s1 = avctx->priv_data;
1120     MpegEncContext *s = &s1->mpeg_enc_ctx;
1121     uint8_t old_permutation[64];
1122
1123     if ((s1->mpeg_enc_ctx_allocated == 0) ||
1124         avctx->coded_width  != s->width   ||
1125         avctx->coded_height != s->height  ||
1126         s1->save_width           != s->width                ||
1127         s1->save_height          != s->height               ||
1128         s1->save_aspect_info     != s->aspect_ratio_info    ||
1129         s1->save_progressive_seq != s->progressive_sequence ||
1130         0)
1131     {
1132
1133         if (s1->mpeg_enc_ctx_allocated) {
1134             ParseContext pc = s->parse_context;
1135             s->parse_context.buffer = 0;
1136             ff_MPV_common_end(s);
1137             s->parse_context = pc;
1138         }
1139
1140         if ((s->width == 0) || (s->height == 0))
1141             return -2;
1142
1143         avcodec_set_dimensions(avctx, s->width, s->height);
1144         avctx->bit_rate          = s->bit_rate;
1145         s1->save_aspect_info     = s->aspect_ratio_info;
1146         s1->save_width           = s->width;
1147         s1->save_height          = s->height;
1148         s1->save_progressive_seq = s->progressive_sequence;
1149
1150         /* low_delay may be forced, in this case we will have B-frames
1151          * that behave like P-frames. */
1152         avctx->has_b_frames = !s->low_delay;
1153
1154         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1155             //MPEG-1 fps
1156             avctx->time_base.den = ff_mpeg12_frame_rate_tab[s->frame_rate_index].num;
1157             avctx->time_base.num = ff_mpeg12_frame_rate_tab[s->frame_rate_index].den;
1158             //MPEG-1 aspect
1159             avctx->sample_aspect_ratio = av_d2q(1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1160             avctx->ticks_per_frame=1;
1161         } else {//MPEG-2
1162         //MPEG-2 fps
1163             av_reduce(&s->avctx->time_base.den,
1164                       &s->avctx->time_base.num,
1165                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
1166                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1167                       1 << 30);
1168             avctx->ticks_per_frame = 2;
1169             //MPEG-2 aspect
1170             if (s->aspect_ratio_info > 1) {
1171                 AVRational dar =
1172                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1173                                       (AVRational) {s1->pan_scan.width, s1->pan_scan.height}),
1174                              (AVRational) {s->width, s->height});
1175
1176                 // we ignore the spec here and guess a bit as reality does not match the spec, see for example
1177                 // res_change_ffmpeg_aspect.ts and sequence-display-aspect.mpg
1178                 // issue1613, 621, 562
1179                 if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1180                    (av_cmp_q(dar, (AVRational) {4, 3}) && av_cmp_q(dar, (AVRational) {16, 9}))) {
1181                     s->avctx->sample_aspect_ratio =
1182                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1183                                  (AVRational) {s->width, s->height});
1184                 } else {
1185                     s->avctx->sample_aspect_ratio =
1186                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1187                                  (AVRational) {s1->pan_scan.width, s1->pan_scan.height});
1188 //issue1613 4/3 16/9 -> 16/9
1189 //res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1190 //widescreen-issue562.mpg 4/3 16/9 -> 16/9
1191 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1192                     av_dlog(avctx, "A %d/%d\n",
1193                             ff_mpeg2_aspect[s->aspect_ratio_info].num, ff_mpeg2_aspect[s->aspect_ratio_info].den);
1194                     av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1195                             s->avctx->sample_aspect_ratio.den);
1196                 }
1197             } else {
1198                 s->avctx->sample_aspect_ratio =
1199                     ff_mpeg2_aspect[s->aspect_ratio_info];
1200             }
1201         } // MPEG-2
1202
1203         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1204         avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1205         // until then pix_fmt may be changed right after codec init
1206         if (avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT ||
1207             avctx->hwaccel                            ||
1208             s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
1209             if (avctx->idct_algo == FF_IDCT_AUTO)
1210                 avctx->idct_algo = FF_IDCT_SIMPLE;
1211
1212         /* Quantization matrices may need reordering
1213          * if DCT permutation is changed. */
1214         memcpy(old_permutation, s->dsp.idct_permutation, 64 * sizeof(uint8_t));
1215
1216         if (ff_MPV_common_init(s) < 0)
1217             return -2;
1218
1219         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->dsp.idct_permutation);
1220         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->dsp.idct_permutation);
1221         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->dsp.idct_permutation);
1222         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->dsp.idct_permutation);
1223
1224         s1->mpeg_enc_ctx_allocated = 1;
1225     }
1226     return 0;
1227 }
1228
1229 static int mpeg1_decode_picture(AVCodecContext *avctx,
1230                                 const uint8_t *buf, int buf_size)
1231 {
1232     Mpeg1Context *s1 = avctx->priv_data;
1233     MpegEncContext *s = &s1->mpeg_enc_ctx;
1234     int ref, f_code, vbv_delay;
1235
1236     init_get_bits(&s->gb, buf, buf_size*8);
1237
1238     ref = get_bits(&s->gb, 10); /* temporal ref */
1239     s->pict_type = get_bits(&s->gb, 3);
1240     if (s->pict_type == 0 || s->pict_type > 3)
1241         return -1;
1242
1243     vbv_delay = get_bits(&s->gb, 16);
1244     if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) {
1245         s->full_pel[0] = get_bits1(&s->gb);
1246         f_code = get_bits(&s->gb, 3);
1247         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1248             return -1;
1249         s->mpeg_f_code[0][0] = f_code;
1250         s->mpeg_f_code[0][1] = f_code;
1251     }
1252     if (s->pict_type == AV_PICTURE_TYPE_B) {
1253         s->full_pel[1] = get_bits1(&s->gb);
1254         f_code = get_bits(&s->gb, 3);
1255         if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
1256             return -1;
1257         s->mpeg_f_code[1][0] = f_code;
1258         s->mpeg_f_code[1][1] = f_code;
1259     }
1260     s->current_picture.f.pict_type = s->pict_type;
1261     s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1262
1263     if (avctx->debug & FF_DEBUG_PICT_INFO)
1264         av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1265
1266     s->y_dc_scale = 8;
1267     s->c_dc_scale = 8;
1268     return 0;
1269 }
1270
1271 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1272 {
1273     MpegEncContext *s= &s1->mpeg_enc_ctx;
1274     int horiz_size_ext, vert_size_ext;
1275     int bit_rate_ext;
1276
1277     skip_bits(&s->gb, 1); /* profile and level esc*/
1278     s->avctx->profile       = get_bits(&s->gb, 3);
1279     s->avctx->level         = get_bits(&s->gb, 4);
1280     s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1281     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1282     horiz_size_ext          = get_bits(&s->gb, 2);
1283     vert_size_ext           = get_bits(&s->gb, 2);
1284     s->width  |= (horiz_size_ext << 12);
1285     s->height |= (vert_size_ext  << 12);
1286     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1287     s->bit_rate += (bit_rate_ext << 18) * 400;
1288     skip_bits1(&s->gb); /* marker */
1289     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1290
1291     s->low_delay = get_bits1(&s->gb);
1292     if (s->flags & CODEC_FLAG_LOW_DELAY)
1293         s->low_delay = 1;
1294
1295     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1296     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1297
1298     av_dlog(s->avctx, "sequence extension\n");
1299     s->codec_id      = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1300
1301     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1302         av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1303                s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1304
1305 }
1306
1307 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1308 {
1309     MpegEncContext *s = &s1->mpeg_enc_ctx;
1310     int color_description, w, h;
1311
1312     skip_bits(&s->gb, 3); /* video format */
1313     color_description = get_bits1(&s->gb);
1314     if (color_description) {
1315         s->avctx->color_primaries = get_bits(&s->gb, 8);
1316         s->avctx->color_trc       = get_bits(&s->gb, 8);
1317         s->avctx->colorspace      = get_bits(&s->gb, 8);
1318     }
1319     w = get_bits(&s->gb, 14);
1320     skip_bits(&s->gb, 1); //marker
1321     h = get_bits(&s->gb, 14);
1322     // remaining 3 bits are zero padding
1323
1324     s1->pan_scan.width  = 16 * w;
1325     s1->pan_scan.height = 16 * h;
1326
1327     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1328         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1329 }
1330
1331 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1332 {
1333     MpegEncContext *s = &s1->mpeg_enc_ctx;
1334     int i, nofco;
1335
1336     nofco = 1;
1337     if (s->progressive_sequence) {
1338         if (s->repeat_first_field) {
1339             nofco++;
1340             if (s->top_field_first)
1341                 nofco++;
1342         }
1343     } else {
1344         if (s->picture_structure == PICT_FRAME) {
1345             nofco++;
1346             if (s->repeat_first_field)
1347                 nofco++;
1348         }
1349     }
1350     for (i = 0; i < nofco; i++) {
1351         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1352         skip_bits(&s->gb, 1); // marker
1353         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1354         skip_bits(&s->gb, 1); // marker
1355     }
1356
1357     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1358         av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1359                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1360                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1361                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1362 }
1363
1364 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64], uint16_t matrix1[64], int intra)
1365 {
1366     int i;
1367
1368     for (i = 0; i < 64; i++) {
1369         int j = s->dsp.idct_permutation[ff_zigzag_direct[i]];
1370         int v = get_bits(&s->gb, 8);
1371         if (v == 0) {
1372             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1373             return -1;
1374         }
1375         if (intra && i == 0 && v != 8) {
1376             av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
1377             v = 8; // needed by pink.mpg / issue1046
1378         }
1379         matrix0[j] = v;
1380         if (matrix1)
1381             matrix1[j] = v;
1382     }
1383     return 0;
1384 }
1385
1386 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1387 {
1388     av_dlog(s->avctx, "matrix extension\n");
1389
1390     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1391     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1392     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_intra_matrix, NULL           , 1);
1393     if (get_bits1(&s->gb)) load_matrix(s, s->chroma_inter_matrix, NULL           , 0);
1394 }
1395
1396 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1397 {
1398     MpegEncContext *s = &s1->mpeg_enc_ctx;
1399
1400     s->full_pel[0] = s->full_pel[1] = 0;
1401     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1402     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1403     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1404     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1405     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1406         av_log(s->avctx, AV_LOG_ERROR, "Missing picture start code, guessing missing values\n");
1407         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1408             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1409                 s->pict_type = AV_PICTURE_TYPE_I;
1410             else
1411                 s->pict_type = AV_PICTURE_TYPE_P;
1412         } else
1413             s->pict_type = AV_PICTURE_TYPE_B;
1414         s->current_picture.f.pict_type = s->pict_type;
1415         s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1416     }
1417     s->intra_dc_precision         = get_bits(&s->gb, 2);
1418     s->picture_structure          = get_bits(&s->gb, 2);
1419     s->top_field_first            = get_bits1(&s->gb);
1420     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1421     s->concealment_motion_vectors = get_bits1(&s->gb);
1422     s->q_scale_type               = get_bits1(&s->gb);
1423     s->intra_vlc_format           = get_bits1(&s->gb);
1424     s->alternate_scan             = get_bits1(&s->gb);
1425     s->repeat_first_field         = get_bits1(&s->gb);
1426     s->chroma_420_type            = get_bits1(&s->gb);
1427     s->progressive_frame          = get_bits1(&s->gb);
1428
1429     if (s->progressive_sequence && !s->progressive_frame) {
1430         s->progressive_frame = 1;
1431         av_log(s->avctx, AV_LOG_ERROR, "interlaced frame in progressive sequence, ignoring\n");
1432     }
1433
1434     if (s->picture_structure == 0 || (s->progressive_frame && s->picture_structure != PICT_FRAME)) {
1435         av_log(s->avctx, AV_LOG_ERROR, "picture_structure %d invalid, ignoring\n", s->picture_structure);
1436         s->picture_structure = PICT_FRAME;
1437     }
1438
1439     if (s->progressive_sequence && !s->frame_pred_frame_dct) {
1440         av_log(s->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
1441     }
1442
1443     if (s->picture_structure == PICT_FRAME) {
1444         s->first_field = 0;
1445         s->v_edge_pos  = 16 * s->mb_height;
1446     } else {
1447         s->first_field ^= 1;
1448         s->v_edge_pos   = 8 * s->mb_height;
1449         memset(s->mbskip_table, 0, s->mb_stride * s->mb_height);
1450     }
1451
1452     if (s->alternate_scan) {
1453         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1454         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1455     } else {
1456         ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1457         ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1458     }
1459
1460     /* composite display not parsed */
1461     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1462     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1463     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1464     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1465     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1466     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1467     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1468     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1469     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1470 }
1471
1472 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1473 {
1474     AVCodecContext *avctx = s->avctx;
1475     Mpeg1Context *s1 = (Mpeg1Context*)s;
1476
1477     /* start frame decoding */
1478     if (s->first_field || s->picture_structure == PICT_FRAME) {
1479         AVFrameSideData *pan_scan;
1480
1481         if (ff_MPV_frame_start(s, avctx) < 0)
1482             return -1;
1483
1484         ff_mpeg_er_frame_start(s);
1485
1486         /* first check if we must repeat the frame */
1487         s->current_picture_ptr->f.repeat_pict = 0;
1488         if (s->repeat_first_field) {
1489             if (s->progressive_sequence) {
1490                 if (s->top_field_first)
1491                     s->current_picture_ptr->f.repeat_pict = 4;
1492                 else
1493                     s->current_picture_ptr->f.repeat_pict = 2;
1494             } else if (s->progressive_frame) {
1495                 s->current_picture_ptr->f.repeat_pict = 1;
1496             }
1497         }
1498
1499         pan_scan = av_frame_new_side_data(&s->current_picture_ptr->f,
1500                                           AV_FRAME_DATA_PANSCAN,
1501                                           sizeof(s1->pan_scan));
1502         if (!pan_scan)
1503             return AVERROR(ENOMEM);
1504         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1505
1506         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1507             ff_thread_finish_setup(avctx);
1508     } else { // second field
1509         int i;
1510
1511         if (!s->current_picture_ptr) {
1512             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1513             return -1;
1514         }
1515
1516         if (s->avctx->hwaccel &&
1517             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1518             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1519                 av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode first field\n");
1520         }
1521
1522         for (i = 0; i < 4; i++) {
1523             s->current_picture.f.data[i] = s->current_picture_ptr->f.data[i];
1524             if (s->picture_structure == PICT_BOTTOM_FIELD) {
1525                 s->current_picture.f.data[i] += s->current_picture_ptr->f.linesize[i];
1526             }
1527         }
1528     }
1529
1530     if (avctx->hwaccel) {
1531         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1532             return -1;
1533     }
1534
1535 // MPV_frame_start will call this function too,
1536 // but we need to call it on every field
1537     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1538         if (ff_xvmc_field_start(s, avctx) < 0)
1539             return -1;
1540
1541     return 0;
1542 }
1543
1544 #define DECODE_SLICE_ERROR -1
1545 #define DECODE_SLICE_OK     0
1546
1547 /**
1548  * Decode a slice.
1549  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1550  * @return DECODE_SLICE_ERROR if the slice is damaged,
1551  *         DECODE_SLICE_OK if this slice is OK
1552  */
1553 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1554                              const uint8_t **buf, int buf_size)
1555 {
1556     AVCodecContext *avctx = s->avctx;
1557     const int field_pic   = s->picture_structure != PICT_FRAME;
1558
1559     s->resync_mb_x =
1560     s->resync_mb_y = -1;
1561
1562     assert(mb_y < s->mb_height);
1563
1564     init_get_bits(&s->gb, *buf, buf_size * 8);
1565
1566     ff_mpeg1_clean_buffers(s);
1567     s->interlaced_dct = 0;
1568
1569     s->qscale = get_qscale(s);
1570
1571     if (s->qscale == 0) {
1572         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1573         return -1;
1574     }
1575
1576     /* extra slice info */
1577     while (get_bits1(&s->gb) != 0) {
1578         skip_bits(&s->gb, 8);
1579     }
1580
1581     s->mb_x = 0;
1582
1583     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1584         skip_bits1(&s->gb);
1585     } else {
1586         while (get_bits_left(&s->gb) > 0) {
1587             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1588                                 MBINCR_VLC_BITS, 2);
1589             if (code < 0) {
1590                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1591                 return -1;
1592             }
1593             if (code >= 33) {
1594                 if (code == 33) {
1595                     s->mb_x += 33;
1596                 }
1597                 /* otherwise, stuffing, nothing to do */
1598             } else {
1599                 s->mb_x += code;
1600                 break;
1601             }
1602         }
1603     }
1604
1605     if (s->mb_x >= (unsigned)s->mb_width) {
1606         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1607         return -1;
1608     }
1609
1610     if (avctx->hwaccel) {
1611         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1612         int start_code = -1;
1613         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1614         if (buf_end < *buf + buf_size)
1615             buf_end -= 4;
1616         s->mb_y = mb_y;
1617         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1618             return DECODE_SLICE_ERROR;
1619         *buf = buf_end;
1620         return DECODE_SLICE_OK;
1621     }
1622
1623     s->resync_mb_x = s->mb_x;
1624     s->resync_mb_y = s->mb_y = mb_y;
1625     s->mb_skip_run = 0;
1626     ff_init_block_index(s);
1627
1628     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1629         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1630              av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n",
1631                     s->qscale, s->mpeg_f_code[0][0], s->mpeg_f_code[0][1], s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1632                     s->pict_type == AV_PICTURE_TYPE_I ? "I" : (s->pict_type == AV_PICTURE_TYPE_P ? "P" : (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1633                     s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1634                     s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1635                     s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1636         }
1637     }
1638
1639     for (;;) {
1640         // If 1, we memcpy blocks in xvmcvideo.
1641         if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration > 1)
1642             ff_xvmc_init_block(s); // set s->block
1643
1644         if (mpeg_decode_mb(s, s->block) < 0)
1645             return -1;
1646
1647         if (s->current_picture.motion_val[0] && !s->encoding) { // note motion_val is normally NULL unless we want to extract the MVs
1648             const int wrap = s->b8_stride;
1649             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1650             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1651             int motion_x, motion_y, dir, i;
1652
1653             for (i = 0; i < 2; i++) {
1654                 for (dir = 0; dir < 2; dir++) {
1655                     if (s->mb_intra || (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1656                         motion_x = motion_y = 0;
1657                     } else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1658                         motion_x = s->mv[dir][0][0];
1659                         motion_y = s->mv[dir][0][1];
1660                     } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1661                         motion_x = s->mv[dir][i][0];
1662                         motion_y = s->mv[dir][i][1];
1663                     }
1664
1665                     s->current_picture.motion_val[dir][xy    ][0] = motion_x;
1666                     s->current_picture.motion_val[dir][xy    ][1] = motion_y;
1667                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1668                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1669                     s->current_picture.ref_index [dir][b8_xy    ] =
1670                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1671                     assert(s->field_select[dir][i] == 0 || s->field_select[dir][i] == 1);
1672                 }
1673                 xy += wrap;
1674                 b8_xy +=2;
1675             }
1676         }
1677
1678         s->dest[0] += 16;
1679         s->dest[1] += 16 >> s->chroma_x_shift;
1680         s->dest[2] += 16 >> s->chroma_x_shift;
1681
1682         ff_MPV_decode_mb(s, s->block);
1683
1684         if (++s->mb_x >= s->mb_width) {
1685             const int mb_size = 16;
1686
1687             ff_mpeg_draw_horiz_band(s, mb_size*(s->mb_y >> field_pic), mb_size);
1688             ff_MPV_report_decode_progress(s);
1689
1690             s->mb_x = 0;
1691             s->mb_y += 1 << field_pic;
1692
1693             if (s->mb_y >= s->mb_height) {
1694                 int left   = get_bits_left(&s->gb);
1695                 int is_d10 = s->chroma_format == 2 && s->pict_type == AV_PICTURE_TYPE_I && avctx->profile == 0 && avctx->level == 5
1696                              && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1697                              && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1698
1699                 if (left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1700                     || ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
1701                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1702                     return -1;
1703                 } else
1704                     goto eos;
1705             }
1706
1707             ff_init_block_index(s);
1708         }
1709
1710         /* skip mb handling */
1711         if (s->mb_skip_run == -1) {
1712             /* read increment again */
1713             s->mb_skip_run = 0;
1714             for (;;) {
1715                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1716                                     MBINCR_VLC_BITS, 2);
1717                 if (code < 0) {
1718                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1719                     return -1;
1720                 }
1721                 if (code >= 33) {
1722                     if (code == 33) {
1723                         s->mb_skip_run += 33;
1724                     } else if (code == 35) {
1725                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1726                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1727                             return -1;
1728                         }
1729                         goto eos; /* end of slice */
1730                     }
1731                     /* otherwise, stuffing, nothing to do */
1732                 } else {
1733                     s->mb_skip_run += code;
1734                     break;
1735                 }
1736             }
1737             if (s->mb_skip_run) {
1738                 int i;
1739                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1740                     av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1741                     return -1;
1742                 }
1743
1744                 /* skip mb */
1745                 s->mb_intra = 0;
1746                 for (i = 0; i < 12; i++)
1747                     s->block_last_index[i] = -1;
1748                 if (s->picture_structure == PICT_FRAME)
1749                     s->mv_type = MV_TYPE_16X16;
1750                 else
1751                     s->mv_type = MV_TYPE_FIELD;
1752                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1753                     /* if P type, zero motion vector is implied */
1754                     s->mv_dir             = MV_DIR_FORWARD;
1755                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1756                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1757                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1758                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1759                 } else {
1760                     /* if B type, reuse previous vectors and directions */
1761                     s->mv[0][0][0] = s->last_mv[0][0][0];
1762                     s->mv[0][0][1] = s->last_mv[0][0][1];
1763                     s->mv[1][0][0] = s->last_mv[1][0][0];
1764                     s->mv[1][0][1] = s->last_mv[1][0][1];
1765                 }
1766             }
1767         }
1768     }
1769 eos: // end of slice
1770     *buf += (get_bits_count(&s->gb)-1)/8;
1771     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1772     return 0;
1773 }
1774
1775 static int slice_decode_thread(AVCodecContext *c, void *arg)
1776 {
1777     MpegEncContext *s   = *(void**)arg;
1778     const uint8_t *buf  = s->gb.buffer;
1779     int mb_y            = s->start_mb_y;
1780     const int field_pic = s->picture_structure != PICT_FRAME;
1781
1782     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
1783
1784     for (;;) {
1785         uint32_t start_code;
1786         int ret;
1787
1788         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
1789         emms_c();
1790         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1791                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
1792                 s->start_mb_y, s->end_mb_y, s->er.error_count);
1793         if (ret < 0) {
1794             if (c->err_recognition & AV_EF_EXPLODE)
1795                 return ret;
1796             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
1797                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
1798         } else {
1799             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
1800         }
1801
1802         if (s->mb_y == s->end_mb_y)
1803             return 0;
1804
1805         start_code = -1;
1806         buf = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
1807         mb_y= (start_code - SLICE_MIN_START_CODE) << field_pic;
1808         if (s->picture_structure == PICT_BOTTOM_FIELD)
1809             mb_y++;
1810         if (mb_y < 0 || mb_y >= s->end_mb_y)
1811             return -1;
1812     }
1813 }
1814
1815 /**
1816  * Handle slice ends.
1817  * @return 1 if it seems to be the last slice
1818  */
1819 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1820 {
1821     Mpeg1Context *s1 = avctx->priv_data;
1822     MpegEncContext *s = &s1->mpeg_enc_ctx;
1823
1824     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1825         return 0;
1826
1827     if (s->avctx->hwaccel) {
1828         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1829             av_log(avctx, AV_LOG_ERROR, "hardware accelerator failed to decode picture\n");
1830     }
1831
1832     if (CONFIG_MPEG_XVMC_DECODER && s->avctx->xvmc_acceleration)
1833         ff_xvmc_field_end(s);
1834
1835     /* end of slice reached */
1836     if (/*s->mb_y << field_pic == s->mb_height &&*/ !s->first_field) {
1837         /* end of image */
1838
1839         ff_er_frame_end(&s->er);
1840
1841         ff_MPV_frame_end(s);
1842
1843         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
1844             int ret = av_frame_ref(pict, &s->current_picture_ptr->f);
1845             if (ret < 0)
1846                 return ret;
1847             ff_print_debug_info(s, s->current_picture_ptr);
1848         } else {
1849             if (avctx->active_thread_type & FF_THREAD_FRAME)
1850                 s->picture_number++;
1851             /* latency of 1 frame for I- and P-frames */
1852             /* XXX: use another variable than picture_number */
1853             if (s->last_picture_ptr != NULL) {
1854                 int ret = av_frame_ref(pict, &s->last_picture_ptr->f);
1855                 if (ret < 0)
1856                     return ret;
1857                 ff_print_debug_info(s, s->last_picture_ptr);
1858             }
1859         }
1860
1861         return 1;
1862     } else {
1863         return 0;
1864     }
1865 }
1866
1867 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1868                                  const uint8_t *buf, int buf_size)
1869 {
1870     Mpeg1Context *s1 = avctx->priv_data;
1871     MpegEncContext *s = &s1->mpeg_enc_ctx;
1872     int width, height;
1873     int i, v, j;
1874
1875     init_get_bits(&s->gb, buf, buf_size*8);
1876
1877     width  = get_bits(&s->gb, 12);
1878     height = get_bits(&s->gb, 12);
1879     if (width == 0 || height == 0) {
1880         av_log(avctx, AV_LOG_WARNING, "Invalid horizontal or vertical size "
1881                "value.\n");
1882         if (avctx->err_recognition & AV_EF_BITSTREAM)
1883             return AVERROR_INVALIDDATA;
1884     }
1885     s->aspect_ratio_info = get_bits(&s->gb, 4);
1886     if (s->aspect_ratio_info == 0) {
1887         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
1888         if (avctx->err_recognition & AV_EF_BITSTREAM)
1889             return -1;
1890     }
1891     s->frame_rate_index = get_bits(&s->gb, 4);
1892     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1893         return -1;
1894     s->bit_rate = get_bits(&s->gb, 18) * 400;
1895     if (get_bits1(&s->gb) == 0) /* marker */
1896         return -1;
1897     s->width  = width;
1898     s->height = height;
1899
1900     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
1901     skip_bits(&s->gb, 1);
1902
1903     /* get matrix */
1904     if (get_bits1(&s->gb)) {
1905         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1906     } else {
1907         for (i = 0; i < 64; i++) {
1908             j = s->dsp.idct_permutation[i];
1909             v = ff_mpeg1_default_intra_matrix[i];
1910             s->intra_matrix[j]        = v;
1911             s->chroma_intra_matrix[j] = v;
1912         }
1913     }
1914     if (get_bits1(&s->gb)) {
1915         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1916     } else {
1917         for (i = 0; i < 64; i++) {
1918             int j = s->dsp.idct_permutation[i];
1919             v = ff_mpeg1_default_non_intra_matrix[i];
1920             s->inter_matrix[j]        = v;
1921             s->chroma_inter_matrix[j] = v;
1922         }
1923     }
1924
1925     if (show_bits(&s->gb, 23) != 0) {
1926         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
1927         return -1;
1928     }
1929
1930     /* we set MPEG-2 parameters so that it emulates MPEG-1 */
1931     s->progressive_sequence = 1;
1932     s->progressive_frame    = 1;
1933     s->picture_structure    = PICT_FRAME;
1934     s->frame_pred_frame_dct = 1;
1935     s->chroma_format        = 1;
1936     s->codec_id             = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
1937     s->out_format           = FMT_MPEG1;
1938     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
1939     if (s->flags & CODEC_FLAG_LOW_DELAY)
1940         s->low_delay = 1;
1941
1942     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1943         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
1944                s->avctx->rc_buffer_size, s->bit_rate);
1945
1946     return 0;
1947 }
1948
1949 static int vcr2_init_sequence(AVCodecContext *avctx)
1950 {
1951     Mpeg1Context *s1 = avctx->priv_data;
1952     MpegEncContext *s = &s1->mpeg_enc_ctx;
1953     int i, v;
1954
1955     /* start new MPEG-1 context decoding */
1956     s->out_format = FMT_MPEG1;
1957     if (s1->mpeg_enc_ctx_allocated) {
1958         ff_MPV_common_end(s);
1959     }
1960     s->width  = avctx->coded_width;
1961     s->height = avctx->coded_height;
1962     avctx->has_b_frames = 0; // true?
1963     s->low_delay = 1;
1964
1965     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1966     avctx->hwaccel = ff_find_hwaccel(avctx->codec->id, avctx->pix_fmt);
1967
1968     if (avctx->pix_fmt == AV_PIX_FMT_XVMC_MPEG2_IDCT || avctx->hwaccel ||
1969         s->avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
1970         if (avctx->idct_algo == FF_IDCT_AUTO)
1971             avctx->idct_algo = FF_IDCT_SIMPLE;
1972
1973     if (ff_MPV_common_init(s) < 0)
1974         return -1;
1975     exchange_uv(s); // common init reset pblocks, so we swap them here
1976     s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
1977     s1->mpeg_enc_ctx_allocated = 1;
1978
1979     for (i = 0; i < 64; i++) {
1980         int j = s->dsp.idct_permutation[i];
1981         v = ff_mpeg1_default_intra_matrix[i];
1982         s->intra_matrix[j]        = v;
1983         s->chroma_intra_matrix[j] = v;
1984
1985         v = ff_mpeg1_default_non_intra_matrix[i];
1986         s->inter_matrix[j]        = v;
1987         s->chroma_inter_matrix[j] = v;
1988     }
1989
1990     s->progressive_sequence  = 1;
1991     s->progressive_frame     = 1;
1992     s->picture_structure     = PICT_FRAME;
1993     s->frame_pred_frame_dct  = 1;
1994     s->chroma_format         = 1;
1995     s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1996     s1->save_width           = s->width;
1997     s1->save_height          = s->height;
1998     s1->save_progressive_seq = s->progressive_sequence;
1999     return 0;
2000 }
2001
2002
2003 static void mpeg_decode_user_data(AVCodecContext *avctx,
2004                                   const uint8_t *p, int buf_size)
2005 {
2006     const uint8_t *buf_end = p + buf_size;
2007
2008     /* we parse the DTG active format information */
2009     if (buf_end - p >= 5 &&
2010         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2011         int flags = p[4];
2012         p += 5;
2013         if (flags & 0x80) {
2014             /* skip event id */
2015             p += 2;
2016         }
2017         if (flags & 0x40) {
2018             if (buf_end - p < 1)
2019                 return;
2020             avctx->dtg_active_format = p[0] & 0x0f;
2021         }
2022     }
2023 }
2024
2025 static void mpeg_decode_gop(AVCodecContext *avctx,
2026                             const uint8_t *buf, int buf_size)
2027 {
2028     Mpeg1Context *s1  = avctx->priv_data;
2029     MpegEncContext *s = &s1->mpeg_enc_ctx;
2030
2031     int time_code_hours, time_code_minutes;
2032     int time_code_seconds, time_code_pictures;
2033     int broken_link;
2034
2035     init_get_bits(&s->gb, buf, buf_size*8);
2036
2037     skip_bits1(&s->gb); /* drop_frame_flag */
2038
2039     time_code_hours   = get_bits(&s->gb, 5);
2040     time_code_minutes = get_bits(&s->gb, 6);
2041     skip_bits1(&s->gb); // marker bit
2042     time_code_seconds  = get_bits(&s->gb, 6);
2043     time_code_pictures = get_bits(&s->gb, 6);
2044
2045     s1->closed_gop = get_bits1(&s->gb);
2046     /*broken_link indicate that after editing the
2047       reference frames of the first B-Frames after GOP I-Frame
2048       are missing (open gop)*/
2049     broken_link = get_bits1(&s->gb);
2050
2051     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2052         av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) closed_gop=%d broken_link=%d\n",
2053                time_code_hours, time_code_minutes, time_code_seconds,
2054                time_code_pictures, s1->closed_gop, broken_link);
2055 }
2056
2057 static int decode_chunks(AVCodecContext *avctx,
2058                          AVFrame *picture, int *got_output,
2059                          const uint8_t *buf, int buf_size)
2060 {
2061     Mpeg1Context *s = avctx->priv_data;
2062     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2063     const uint8_t *buf_ptr = buf;
2064     const uint8_t *buf_end = buf + buf_size;
2065     int ret, input_size;
2066     int last_code = 0;
2067
2068     for (;;) {
2069         /* find next start code */
2070         uint32_t start_code = -1;
2071         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2072         if (start_code > 0x1ff) {
2073             if (s2->pict_type != AV_PICTURE_TYPE_B || avctx->skip_frame <= AVDISCARD_DEFAULT) {
2074                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2075                     int i;
2076
2077                     avctx->execute(avctx, slice_decode_thread,  &s2->thread_context[0], NULL, s->slice_count, sizeof(void*));
2078                     for (i = 0; i < s->slice_count; i++)
2079                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2080                 }
2081
2082                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2083                     && avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU)
2084                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2085
2086                 ret = slice_end(avctx, picture);
2087                 if (ret < 0)
2088                     return ret;
2089                 else if (ret) {
2090                     if (s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2091                         *got_output = 1;
2092                 }
2093             }
2094             s2->pict_type = 0;
2095             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2096         }
2097
2098         input_size = buf_end - buf_ptr;
2099
2100         if (avctx->debug & FF_DEBUG_STARTCODE) {
2101             av_log(avctx, AV_LOG_DEBUG, "%3X at %td left %d\n", start_code, buf_ptr-buf, input_size);
2102         }
2103
2104         /* prepare data for next start code */
2105         switch (start_code) {
2106         case SEQ_START_CODE:
2107             if (last_code == 0) {
2108                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2109                 s->sync=1;
2110             } else {
2111                 av_log(avctx, AV_LOG_ERROR, "ignoring SEQ_START_CODE after %X\n", last_code);
2112                 if (avctx->err_recognition & AV_EF_EXPLODE)
2113                     return AVERROR_INVALIDDATA;
2114             }
2115             break;
2116
2117         case PICTURE_START_CODE:
2118             if (s2->width <= 0 || s2->height <= 0) {
2119                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2120                        s2->width, s2->height);
2121                 return AVERROR_INVALIDDATA;
2122             }
2123
2124             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) && s->slice_count) {
2125                 int i;
2126
2127                 avctx->execute(avctx, slice_decode_thread,
2128                                s2->thread_context, NULL,
2129                                s->slice_count, sizeof(void*));
2130                 for (i = 0; i < s->slice_count; i++)
2131                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2132                 s->slice_count = 0;
2133             }
2134             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2135                 ret = mpeg_decode_postinit(avctx);
2136                 if (ret < 0) {
2137                     av_log(avctx, AV_LOG_ERROR, "mpeg_decode_postinit() failure\n");
2138                     return ret;
2139                 }
2140
2141                 /* we have a complete image: we try to decompress it */
2142                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2143                     s2->pict_type = 0;
2144                 s2->first_slice = 1;
2145                 last_code = PICTURE_START_CODE;
2146             } else {
2147                 av_log(avctx, AV_LOG_ERROR, "ignoring pic after %X\n", last_code);
2148                 if (avctx->err_recognition & AV_EF_EXPLODE)
2149                     return AVERROR_INVALIDDATA;
2150             }
2151             break;
2152         case EXT_START_CODE:
2153             init_get_bits(&s2->gb, buf_ptr, input_size*8);
2154
2155             switch (get_bits(&s2->gb, 4)) {
2156             case 0x1:
2157                 if (last_code == 0) {
2158                 mpeg_decode_sequence_extension(s);
2159                 } else {
2160                     av_log(avctx, AV_LOG_ERROR, "ignoring seq ext after %X\n", last_code);
2161                     if (avctx->err_recognition & AV_EF_EXPLODE)
2162                         return AVERROR_INVALIDDATA;
2163                 }
2164                 break;
2165             case 0x2:
2166                 mpeg_decode_sequence_display_extension(s);
2167                 break;
2168             case 0x3:
2169                 mpeg_decode_quant_matrix_extension(s2);
2170                 break;
2171             case 0x7:
2172                 mpeg_decode_picture_display_extension(s);
2173                 break;
2174             case 0x8:
2175                 if (last_code == PICTURE_START_CODE) {
2176                     mpeg_decode_picture_coding_extension(s);
2177                 } else {
2178                     av_log(avctx, AV_LOG_ERROR, "ignoring pic cod ext after %X\n", last_code);
2179                     if (avctx->err_recognition & AV_EF_EXPLODE)
2180                         return AVERROR_INVALIDDATA;
2181                 }
2182                 break;
2183             }
2184             break;
2185         case USER_START_CODE:
2186             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2187             break;
2188         case GOP_START_CODE:
2189             if (last_code == 0) {
2190                 s2->first_field=0;
2191                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2192                 s->sync=1;
2193             } else {
2194                 av_log(avctx, AV_LOG_ERROR, "ignoring GOP_START_CODE after %X\n", last_code);
2195                 if (avctx->err_recognition & AV_EF_EXPLODE)
2196                     return AVERROR_INVALIDDATA;
2197             }
2198             break;
2199         default:
2200             if (start_code >= SLICE_MIN_START_CODE &&
2201                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2202                 const int field_pic = s2->picture_structure != PICT_FRAME;
2203                 int mb_y = (start_code - SLICE_MIN_START_CODE) << field_pic;
2204                 last_code = SLICE_MIN_START_CODE;
2205
2206                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2207                     mb_y++;
2208
2209                 if (mb_y >= s2->mb_height) {
2210                     av_log(s2->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2211                     return -1;
2212                 }
2213
2214                 if (s2->last_picture_ptr == NULL) {
2215                 /* Skip B-frames if we do not have reference frames and gop is not closed */
2216                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2217                         if (!s->closed_gop)
2218                             break;
2219                     }
2220                 }
2221                 if (s2->pict_type == AV_PICTURE_TYPE_I)
2222                     s->sync=1;
2223                 if (s2->next_picture_ptr == NULL) {
2224                 /* Skip P-frames if we do not have a reference frame or we have an invalid header. */
2225                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) break;
2226                 }
2227                 if ((avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type == AV_PICTURE_TYPE_B) ||
2228                     (avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type != AV_PICTURE_TYPE_I) ||
2229                      avctx->skip_frame >= AVDISCARD_ALL)
2230                     break;
2231
2232                 if (!s->mpeg_enc_ctx_allocated)
2233                     break;
2234
2235                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2236                     if (mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2237                         break;
2238                 }
2239
2240                 if (!s2->pict_type) {
2241                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2242                     if (avctx->err_recognition & AV_EF_EXPLODE)
2243                         return AVERROR_INVALIDDATA;
2244                     break;
2245                 }
2246
2247                 if (s2->first_slice) {
2248                     s2->first_slice = 0;
2249                     if (mpeg_field_start(s2, buf, buf_size) < 0)
2250                         return -1;
2251                 }
2252                 if (!s2->current_picture_ptr) {
2253                     av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2254                     return AVERROR_INVALIDDATA;
2255                 }
2256
2257                 if (avctx->codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
2258                     s->slice_count++;
2259                     break;
2260                 }
2261
2262                 if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE)) {
2263                     int threshold = (s2->mb_height * s->slice_count +
2264                                      s2->slice_context_count / 2) /
2265                                     s2->slice_context_count;
2266                     if (threshold <= mb_y) {
2267                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2268
2269                         thread_context->start_mb_y = mb_y;
2270                         thread_context->end_mb_y   = s2->mb_height;
2271                         if (s->slice_count) {
2272                             s2->thread_context[s->slice_count-1]->end_mb_y = mb_y;
2273                             ret = ff_update_duplicate_context(thread_context,
2274                                                               s2);
2275                             if (ret < 0)
2276                                 return ret;
2277                         }
2278                         init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2279                         s->slice_count++;
2280                     }
2281                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2282                 } else {
2283                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2284                     emms_c();
2285
2286                     if (ret < 0) {
2287                         if (avctx->err_recognition & AV_EF_EXPLODE)
2288                             return ret;
2289                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2290                             ff_er_add_slice(&s2->er, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2291                     } else {
2292                         ff_er_add_slice(&s2->er, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, ER_AC_END | ER_DC_END | ER_MV_END);
2293                     }
2294                 }
2295             }
2296             break;
2297         }
2298     }
2299 }
2300
2301 static int mpeg_decode_frame(AVCodecContext *avctx,
2302                              void *data, int *got_output,
2303                              AVPacket *avpkt)
2304 {
2305     const uint8_t *buf = avpkt->data;
2306     int buf_size = avpkt->size;
2307     Mpeg1Context *s = avctx->priv_data;
2308     AVFrame *picture = data;
2309     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2310     av_dlog(avctx, "fill_buffer\n");
2311
2312     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2313         /* special case for last picture */
2314         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2315             int ret = av_frame_ref(picture, &s2->next_picture_ptr->f);
2316             if (ret < 0)
2317                 return ret;
2318
2319             s2->next_picture_ptr = NULL;
2320
2321             *got_output = 1;
2322         }
2323         return buf_size;
2324     }
2325
2326     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2327         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size, NULL);
2328
2329         if (ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0)
2330             return buf_size;
2331     }
2332
2333     if (s->mpeg_enc_ctx_allocated == 0 && avctx->codec_tag == AV_RL32("VCR2"))
2334         vcr2_init_sequence(avctx);
2335
2336     s->slice_count = 0;
2337
2338     if (avctx->extradata && !s->extradata_decoded) {
2339         int ret = decode_chunks(avctx, picture, got_output, avctx->extradata, avctx->extradata_size);
2340         s->extradata_decoded = 1;
2341         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
2342             return ret;
2343     }
2344
2345     return decode_chunks(avctx, picture, got_output, buf, buf_size);
2346 }
2347
2348
2349 static void flush(AVCodecContext *avctx)
2350 {
2351     Mpeg1Context *s = avctx->priv_data;
2352
2353     s->sync=0;
2354     s->closed_gop = 0;
2355
2356     ff_mpeg_flush(avctx);
2357 }
2358
2359 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2360 {
2361     Mpeg1Context *s = avctx->priv_data;
2362
2363     if (s->mpeg_enc_ctx_allocated)
2364         ff_MPV_common_end(&s->mpeg_enc_ctx);
2365     return 0;
2366 }
2367
2368 static const AVProfile mpeg2_video_profiles[] = {
2369     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2370     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2371     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2372     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2373     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2374     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2375     { FF_PROFILE_RESERVED,           "Reserved"           },
2376     { FF_PROFILE_RESERVED,           "Reserved"           },
2377     { FF_PROFILE_UNKNOWN },
2378 };
2379
2380
2381 AVCodec ff_mpeg1video_decoder = {
2382     .name                  = "mpeg1video",
2383     .type                  = AVMEDIA_TYPE_VIDEO,
2384     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2385     .priv_data_size        = sizeof(Mpeg1Context),
2386     .init                  = mpeg_decode_init,
2387     .close                 = mpeg_decode_end,
2388     .decode                = mpeg_decode_frame,
2389     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2390                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2391                              CODEC_CAP_SLICE_THREADS,
2392     .flush                 = flush,
2393     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2394     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2395 };
2396
2397 AVCodec ff_mpeg2video_decoder = {
2398     .name           = "mpeg2video",
2399     .type           = AVMEDIA_TYPE_VIDEO,
2400     .id             = AV_CODEC_ID_MPEG2VIDEO,
2401     .priv_data_size = sizeof(Mpeg1Context),
2402     .init           = mpeg_decode_init,
2403     .close          = mpeg_decode_end,
2404     .decode         = mpeg_decode_frame,
2405     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2406                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2407                       CODEC_CAP_SLICE_THREADS,
2408     .flush          = flush,
2409     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2410     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2411 };
2412
2413 #if CONFIG_MPEG_XVMC_DECODER
2414 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2415 {
2416     if (avctx->active_thread_type & FF_THREAD_SLICE)
2417         return -1;
2418     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2419         return -1;
2420     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2421         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2422     }
2423     mpeg_decode_init(avctx);
2424
2425     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2426     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2427
2428     return 0;
2429 }
2430
2431 AVCodec ff_mpeg_xvmc_decoder = {
2432     .name           = "mpegvideo_xvmc",
2433     .type           = AVMEDIA_TYPE_VIDEO,
2434     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2435     .priv_data_size = sizeof(Mpeg1Context),
2436     .init           = mpeg_mc_decode_init,
2437     .close          = mpeg_decode_end,
2438     .decode         = mpeg_decode_frame,
2439     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2440                       CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2441     .flush          = flush,
2442     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2443 };
2444
2445 #endif
2446
2447 #if CONFIG_MPEG_VDPAU_DECODER
2448 AVCodec ff_mpeg_vdpau_decoder = {
2449     .name           = "mpegvideo_vdpau",
2450     .type           = AVMEDIA_TYPE_VIDEO,
2451     .id             = AV_CODEC_ID_MPEG2VIDEO,
2452     .priv_data_size = sizeof(Mpeg1Context),
2453     .init           = mpeg_decode_init,
2454     .close          = mpeg_decode_end,
2455     .decode         = mpeg_decode_frame,
2456     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2457                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2458     .flush          = flush,
2459     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2460 };
2461 #endif
2462
2463 #if CONFIG_MPEG1_VDPAU_DECODER
2464 AVCodec ff_mpeg1_vdpau_decoder = {
2465     .name           = "mpeg1video_vdpau",
2466     .type           = AVMEDIA_TYPE_VIDEO,
2467     .id             = AV_CODEC_ID_MPEG1VIDEO,
2468     .priv_data_size = sizeof(Mpeg1Context),
2469     .init           = mpeg_decode_init,
2470     .close          = mpeg_decode_end,
2471     .decode         = mpeg_decode_frame,
2472     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2473                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2474     .flush          = flush,
2475     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2476 };
2477 #endif