1 /*
2  * MPEG-1/2 decoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2002-2013 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * MPEG-1/2 decoder
26  */
27 
28 #define UNCHECKED_BITSTREAM_READER 1
29 #include <inttypes.h>
30 
31 #include "libavutil/attributes.h"
32 #include "libavutil/internal.h"
33 #include "libavutil/stereo3d.h"
34 
35 #include "avcodec.h"
36 #include "bytestream.h"
37 #include "error_resilience.h"
38 #include "idctdsp.h"
39 #include "internal.h"
40 #include "mpeg_er.h"
41 #include "mpeg12.h"
42 #include "mpeg12data.h"
43 #include "mpegutils.h"
44 #include "mpegvideo.h"
45 #include "thread.h"
46 #include "version.h"
47 #include "vdpau_internal.h"
48 #include "xvmc_internal.h"
49 
50 typedef struct Mpeg1Context {
51     MpegEncContext mpeg_enc_ctx;
52     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
53     int repeat_field;           /* true if we must repeat the field */
54     AVPanScan pan_scan;         /* some temporary storage for the panscan */
55     AVStereo3D stereo3d;
56     int has_stereo3d;
57     uint8_t *a53_caption;
58     int a53_caption_size;
59     uint8_t afd;
60     int has_afd;
61     int slice_count;
62     int save_aspect_info;
63     int save_width, save_height, save_progressive_seq;
64     AVRational frame_rate_ext;  /* MPEG-2 specific framerate modificator */
65     int sync;                   /* Did we reach a sync point like a GOP/SEQ/KEYFrame? */
66     int tmpgexs;
67     int first_slice;
68     int extradata_decoded;
69 } Mpeg1Context;
70 
71 #define MB_TYPE_ZERO_MV   0x20000000
72 
73 static const uint32_t ptype2mb_type[7] = {
74                     MB_TYPE_INTRA,
75                     MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
76                     MB_TYPE_L0,
77                     MB_TYPE_L0 | MB_TYPE_CBP,
78     MB_TYPE_QUANT | MB_TYPE_INTRA,
79     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_ZERO_MV | MB_TYPE_16x16,
80     MB_TYPE_QUANT | MB_TYPE_L0 | MB_TYPE_CBP,
81 };
82 
83 static const uint32_t btype2mb_type[11] = {
84                     MB_TYPE_INTRA,
85                     MB_TYPE_L1,
86                     MB_TYPE_L1   | MB_TYPE_CBP,
87                     MB_TYPE_L0,
88                     MB_TYPE_L0   | MB_TYPE_CBP,
89                     MB_TYPE_L0L1,
90                     MB_TYPE_L0L1 | MB_TYPE_CBP,
91     MB_TYPE_QUANT | MB_TYPE_INTRA,
92     MB_TYPE_QUANT | MB_TYPE_L1   | MB_TYPE_CBP,
93     MB_TYPE_QUANT | MB_TYPE_L0   | MB_TYPE_CBP,
94     MB_TYPE_QUANT | MB_TYPE_L0L1 | MB_TYPE_CBP,
95 };
96 
97 static const uint8_t non_linear_qscale[32] = {
98      0,  1,  2,  3,  4,  5,   6,   7,
99      8, 10, 12, 14, 16, 18,  20,  22,
100     24, 28, 32, 36, 40, 44,  48,  52,
101     56, 64, 72, 80, 88, 96, 104, 112,
102 };
103 
104 /* as H.263, but only 17 codes */
mpeg_decode_motion(MpegEncContext * s,int fcode,int pred)105 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
106 {
107     int code, sign, val, shift;
108 
109     code = get_vlc2(&s->gb, ff_mv_vlc.table, MV_VLC_BITS, 2);
110     if (code == 0)
111         return pred;
112     if (code < 0)
113         return 0xffff;
114 
115     sign  = get_bits1(&s->gb);
116     shift = fcode - 1;
117     val   = code;
118     if (shift) {
119         val  = (val - 1) << shift;
120         val |= get_bits(&s->gb, shift);
121         val++;
122     }
123     if (sign)
124         val = -val;
125     val += pred;
126 
127     /* modulo decoding */
128     return sign_extend(val, 5 + shift);
129 }
130 
131 #define check_scantable_index(ctx, x)                                         \
132     do {                                                                      \
133         if ((x) > 63) {                                                       \
134             av_log(ctx->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n",     \
135                    ctx->mb_x, ctx->mb_y);                                     \
136             return AVERROR_INVALIDDATA;                                       \
137         }                                                                     \
138     } while (0)
139 
mpeg1_decode_block_intra(MpegEncContext * s,int16_t * block,int n)140 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
141                                            int16_t *block, int n)
142 {
143     int level, dc, diff, i, j, run;
144     int component;
145     RLTable *rl                  = &ff_rl_mpeg1;
146     uint8_t *const scantable     = s->intra_scantable.permutated;
147     const uint16_t *quant_matrix = s->intra_matrix;
148     const int qscale             = s->qscale;
149 
150     /* DC coefficient */
151     component = (n <= 3 ? 0 : n - 4 + 1);
152     diff = decode_dc(&s->gb, component);
153     if (diff >= 0xffff)
154         return -1;
155     dc  = s->last_dc[component];
156     dc += diff;
157     s->last_dc[component] = dc;
158     block[0] = dc * quant_matrix[0];
159     av_dlog(s->avctx, "dc=%d diff=%d\n", dc, diff);
160     i = 0;
161     {
162         OPEN_READER(re, &s->gb);
163         UPDATE_CACHE(re, &s->gb);
164         if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
165             goto end;
166 
167         /* now quantify & encode AC coefficients */
168         for (;;) {
169             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
170                        TEX_VLC_BITS, 2, 0);
171 
172             if (level != 0) {
173                 i += run;
174                 check_scantable_index(s, i);
175                 j = scantable[i];
176                 level = (level * qscale * quant_matrix[j]) >> 4;
177                 level = (level - 1) | 1;
178                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
179                         SHOW_SBITS(re, &s->gb, 1);
180                 SKIP_BITS(re, &s->gb, 1);
181             } else {
182                 /* escape */
183                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
184                 LAST_SKIP_BITS(re, &s->gb, 6);
185                 UPDATE_CACHE(re, &s->gb);
186                 level = SHOW_SBITS(re, &s->gb, 8);
187                 SKIP_BITS(re, &s->gb, 8);
188                 if (level == -128) {
189                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
190                     SKIP_BITS(re, &s->gb, 8);
191                 } else if (level == 0) {
192                     level = SHOW_UBITS(re, &s->gb, 8);
193                     SKIP_BITS(re, &s->gb, 8);
194                 }
195                 i += run;
196                 check_scantable_index(s, i);
197                 j = scantable[i];
198                 if (level < 0) {
199                     level = -level;
200                     level = (level * qscale * quant_matrix[j]) >> 4;
201                     level = (level - 1) | 1;
202                     level = -level;
203                 } else {
204                     level = (level * qscale * quant_matrix[j]) >> 4;
205                     level = (level - 1) | 1;
206                 }
207             }
208 
209             block[j] = level;
210             if (((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
211                break;
212 
213             UPDATE_CACHE(re, &s->gb);
214         }
215 end:
216         LAST_SKIP_BITS(re, &s->gb, 2);
217         CLOSE_READER(re, &s->gb);
218     }
219     s->block_last_index[n] = i;
220     return 0;
221 }
222 
ff_mpeg1_decode_block_intra(MpegEncContext * s,int16_t * block,int n)223 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
224 {
225     return mpeg1_decode_block_intra(s, block, n);
226 }
227 
mpeg1_decode_block_inter(MpegEncContext * s,int16_t * block,int n)228 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
229                                            int16_t *block, int n)
230 {
231     int level, i, j, run;
232     RLTable *rl                  = &ff_rl_mpeg1;
233     uint8_t *const scantable     = s->intra_scantable.permutated;
234     const uint16_t *quant_matrix = s->inter_matrix;
235     const int qscale             = s->qscale;
236 
237     {
238         OPEN_READER(re, &s->gb);
239         i = -1;
240         // special case for first coefficient, no need to add second VLC table
241         UPDATE_CACHE(re, &s->gb);
242         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
243             level = (3 * qscale * quant_matrix[0]) >> 5;
244             level = (level - 1) | 1;
245             if (GET_CACHE(re, &s->gb) & 0x40000000)
246                 level = -level;
247             block[0] = level;
248             i++;
249             SKIP_BITS(re, &s->gb, 2);
250             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
251                 goto end;
252         }
253         /* now quantify & encode AC coefficients */
254         for (;;) {
255             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
256                        TEX_VLC_BITS, 2, 0);
257 
258             if (level != 0) {
259                 i += run;
260                 check_scantable_index(s, i);
261                 j = scantable[i];
262                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
263                 level = (level - 1) | 1;
264                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
265                         SHOW_SBITS(re, &s->gb, 1);
266                 SKIP_BITS(re, &s->gb, 1);
267             } else {
268                 /* escape */
269                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
270                 LAST_SKIP_BITS(re, &s->gb, 6);
271                 UPDATE_CACHE(re, &s->gb);
272                 level = SHOW_SBITS(re, &s->gb, 8);
273                 SKIP_BITS(re, &s->gb, 8);
274                 if (level == -128) {
275                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
276                     SKIP_BITS(re, &s->gb, 8);
277                 } else if (level == 0) {
278                     level = SHOW_UBITS(re, &s->gb, 8);
279                     SKIP_BITS(re, &s->gb, 8);
280                 }
281                 i += run;
282                 check_scantable_index(s, i);
283                 j = scantable[i];
284                 if (level < 0) {
285                     level = -level;
286                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
287                     level = (level - 1) | 1;
288                     level = -level;
289                 } else {
290                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
291                     level = (level - 1) | 1;
292                 }
293             }
294 
295             block[j] = level;
296             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
297                 break;
298             UPDATE_CACHE(re, &s->gb);
299         }
300 end:
301         LAST_SKIP_BITS(re, &s->gb, 2);
302         CLOSE_READER(re, &s->gb);
303     }
304     s->block_last_index[n] = i;
305     return 0;
306 }
307 
308 /**
309  * Note: this function can read out of range and crash for corrupt streams.
310  * Changing this would eat up any speed benefits it has.
311  * Do not use "fast" flag if you need the code to be robust.
312  */
mpeg1_fast_decode_block_inter(MpegEncContext * s,int16_t * block,int n)313 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s,
314                                                 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 int qscale         = s->qscale;
320 
321     {
322         OPEN_READER(re, &s->gb);
323         i = -1;
324         // Special case for first coefficient, no need to add second VLC table.
325         UPDATE_CACHE(re, &s->gb);
326         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
327             level = (3 * qscale) >> 1;
328             level = (level - 1) | 1;
329             if (GET_CACHE(re, &s->gb) & 0x40000000)
330                 level = -level;
331             block[0] = level;
332             i++;
333             SKIP_BITS(re, &s->gb, 2);
334             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
335                 goto end;
336         }
337 
338         /* now quantify & encode AC coefficients */
339         for (;;) {
340             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
341                        TEX_VLC_BITS, 2, 0);
342 
343             if (level != 0) {
344                 i += run;
345                 check_scantable_index(s, i);
346                 j = scantable[i];
347                 level = ((level * 2 + 1) * qscale) >> 1;
348                 level = (level - 1) | 1;
349                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
350                         SHOW_SBITS(re, &s->gb, 1);
351                 SKIP_BITS(re, &s->gb, 1);
352             } else {
353                 /* escape */
354                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
355                 LAST_SKIP_BITS(re, &s->gb, 6);
356                 UPDATE_CACHE(re, &s->gb);
357                 level = SHOW_SBITS(re, &s->gb, 8);
358                 SKIP_BITS(re, &s->gb, 8);
359                 if (level == -128) {
360                     level = SHOW_UBITS(re, &s->gb, 8) - 256;
361                     SKIP_BITS(re, &s->gb, 8);
362                 } else if (level == 0) {
363                     level = SHOW_UBITS(re, &s->gb, 8);
364                     SKIP_BITS(re, &s->gb, 8);
365                 }
366                 i += run;
367                 check_scantable_index(s, i);
368                 j = scantable[i];
369                 if (level < 0) {
370                     level = -level;
371                     level = ((level * 2 + 1) * qscale) >> 1;
372                     level = (level - 1) | 1;
373                     level = -level;
374                 } else {
375                     level = ((level * 2 + 1) * qscale) >> 1;
376                     level = (level - 1) | 1;
377                 }
378             }
379 
380             block[j] = level;
381             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
382                 break;
383             UPDATE_CACHE(re, &s->gb);
384         }
385 end:
386         LAST_SKIP_BITS(re, &s->gb, 2);
387         CLOSE_READER(re, &s->gb);
388     }
389     s->block_last_index[n] = i;
390     return 0;
391 }
392 
mpeg2_decode_block_non_intra(MpegEncContext * s,int16_t * block,int n)393 static inline int mpeg2_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 uint16_t *quant_matrix;
400     const int qscale = s->qscale;
401     int mismatch;
402 
403     mismatch = 1;
404 
405     {
406         OPEN_READER(re, &s->gb);
407         i = -1;
408         if (n < 4)
409             quant_matrix = s->inter_matrix;
410         else
411             quant_matrix = s->chroma_inter_matrix;
412 
413         // Special case for first coefficient, no need to add second VLC table.
414         UPDATE_CACHE(re, &s->gb);
415         if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
416             level = (3 * qscale * quant_matrix[0]) >> 5;
417             if (GET_CACHE(re, &s->gb) & 0x40000000)
418                 level = -level;
419             block[0]  = level;
420             mismatch ^= level;
421             i++;
422             SKIP_BITS(re, &s->gb, 2);
423             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
424                 goto end;
425         }
426 
427         /* now quantify & encode AC coefficients */
428         for (;;) {
429             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
430                        TEX_VLC_BITS, 2, 0);
431 
432             if (level != 0) {
433                 i += run;
434                 check_scantable_index(s, i);
435                 j = scantable[i];
436                 level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
437                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
438                         SHOW_SBITS(re, &s->gb, 1);
439                 SKIP_BITS(re, &s->gb, 1);
440             } else {
441                 /* escape */
442                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
443                 LAST_SKIP_BITS(re, &s->gb, 6);
444                 UPDATE_CACHE(re, &s->gb);
445                 level = SHOW_SBITS(re, &s->gb, 12);
446                 SKIP_BITS(re, &s->gb, 12);
447 
448                 i += run;
449                 check_scantable_index(s, i);
450                 j = scantable[i];
451                 if (level < 0) {
452                     level = ((-level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
453                     level = -level;
454                 } else {
455                     level = ((level * 2 + 1) * qscale * quant_matrix[j]) >> 5;
456                 }
457             }
458 
459             mismatch ^= level;
460             block[j]  = level;
461             if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
462                 break;
463             UPDATE_CACHE(re, &s->gb);
464         }
465 end:
466         LAST_SKIP_BITS(re, &s->gb, 2);
467         CLOSE_READER(re, &s->gb);
468     }
469     block[63] ^= (mismatch & 1);
470 
471     s->block_last_index[n] = i;
472     return 0;
473 }
474 
475 /**
476  * Note: this function can read out of range and crash for corrupt streams.
477  * Changing this would eat up any speed benefits it has.
478  * Do not use "fast" flag if you need the code to be robust.
479  */
mpeg2_fast_decode_block_non_intra(MpegEncContext * s,int16_t * block,int n)480 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
481                                                     int16_t *block, int n)
482 {
483     int level, i, j, run;
484     RLTable *rl              = &ff_rl_mpeg1;
485     uint8_t *const scantable = s->intra_scantable.permutated;
486     const int qscale         = s->qscale;
487     OPEN_READER(re, &s->gb);
488     i = -1;
489 
490     // special case for first coefficient, no need to add second VLC table
491     UPDATE_CACHE(re, &s->gb);
492     if (((int32_t) GET_CACHE(re, &s->gb)) < 0) {
493         level = (3 * qscale) >> 1;
494         if (GET_CACHE(re, &s->gb) & 0x40000000)
495             level = -level;
496         block[0] = level;
497         i++;
498         SKIP_BITS(re, &s->gb, 2);
499         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF)
500             goto end;
501     }
502 
503     /* now quantify & encode AC coefficients */
504     for (;;) {
505         GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
506 
507         if (level != 0) {
508             i += run;
509             j = scantable[i];
510             level = ((level * 2 + 1) * qscale) >> 1;
511             level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
512                     SHOW_SBITS(re, &s->gb, 1);
513             SKIP_BITS(re, &s->gb, 1);
514         } else {
515             /* escape */
516             run = SHOW_UBITS(re, &s->gb, 6) + 1;
517             LAST_SKIP_BITS(re, &s->gb, 6);
518             UPDATE_CACHE(re, &s->gb);
519             level = SHOW_SBITS(re, &s->gb, 12);
520             SKIP_BITS(re, &s->gb, 12);
521 
522             i += run;
523             j = scantable[i];
524             if (level < 0) {
525                 level = ((-level * 2 + 1) * qscale) >> 1;
526                 level = -level;
527             } else {
528                 level = ((level * 2 + 1) * qscale) >> 1;
529             }
530         }
531 
532         block[j] = level;
533         if (((int32_t) GET_CACHE(re, &s->gb)) <= (int32_t) 0xBFFFFFFF || i > 63)
534             break;
535 
536         UPDATE_CACHE(re, &s->gb);
537     }
538 end:
539     LAST_SKIP_BITS(re, &s->gb, 2);
540     CLOSE_READER(re, &s->gb);
541     s->block_last_index[n] = i;
542     return 0;
543 }
544 
mpeg2_decode_block_intra(MpegEncContext * s,int16_t * block,int n)545 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
546                                            int16_t *block, int n)
547 {
548     int level, dc, diff, i, j, run;
549     int component;
550     RLTable *rl;
551     uint8_t *const scantable = s->intra_scantable.permutated;
552     const uint16_t *quant_matrix;
553     const int qscale = s->qscale;
554     int mismatch;
555 
556     /* DC coefficient */
557     if (n < 4) {
558         quant_matrix = s->intra_matrix;
559         component    = 0;
560     } else {
561         quant_matrix = s->chroma_intra_matrix;
562         component    = (n & 1) + 1;
563     }
564     diff = decode_dc(&s->gb, component);
565     if (diff >= 0xffff)
566         return -1;
567     dc  = s->last_dc[component];
568     dc += diff;
569     s->last_dc[component] = dc;
570     block[0] = dc << (3 - s->intra_dc_precision);
571     av_dlog(s->avctx, "dc=%d\n", block[0]);
572     mismatch = block[0] ^ 1;
573     i = 0;
574     if (s->intra_vlc_format)
575         rl = &ff_rl_mpeg2;
576     else
577         rl = &ff_rl_mpeg1;
578 
579     {
580         OPEN_READER(re, &s->gb);
581         /* now quantify & encode AC coefficients */
582         for (;;) {
583             UPDATE_CACHE(re, &s->gb);
584             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
585                        TEX_VLC_BITS, 2, 0);
586 
587             if (level == 127) {
588                 break;
589             } else if (level != 0) {
590                 i += run;
591                 check_scantable_index(s, i);
592                 j = scantable[i];
593                 level = (level * qscale * quant_matrix[j]) >> 4;
594                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
595                         SHOW_SBITS(re, &s->gb, 1);
596                 LAST_SKIP_BITS(re, &s->gb, 1);
597             } else {
598                 /* escape */
599                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
600                 LAST_SKIP_BITS(re, &s->gb, 6);
601                 UPDATE_CACHE(re, &s->gb);
602                 level = SHOW_SBITS(re, &s->gb, 12);
603                 SKIP_BITS(re, &s->gb, 12);
604                 i += run;
605                 check_scantable_index(s, i);
606                 j = scantable[i];
607                 if (level < 0) {
608                     level = (-level * qscale * quant_matrix[j]) >> 4;
609                     level = -level;
610                 } else {
611                     level = (level * qscale * quant_matrix[j]) >> 4;
612                 }
613             }
614 
615             mismatch ^= level;
616             block[j]  = level;
617         }
618         CLOSE_READER(re, &s->gb);
619     }
620     block[63] ^= mismatch & 1;
621 
622     s->block_last_index[n] = i;
623     return 0;
624 }
625 
626 /**
627  * Note: this function can read out of range and crash for corrupt streams.
628  * Changing this would eat up any speed benefits it has.
629  * Do not use "fast" flag if you need the code to be robust.
630  */
mpeg2_fast_decode_block_intra(MpegEncContext * s,int16_t * block,int n)631 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
632                                                 int16_t *block, int n)
633 {
634     int level, dc, diff, i, j, run;
635     int component;
636     RLTable *rl;
637     uint8_t *const scantable = s->intra_scantable.permutated;
638     const uint16_t *quant_matrix;
639     const int qscale = s->qscale;
640 
641     /* DC coefficient */
642     if (n < 4) {
643         quant_matrix = s->intra_matrix;
644         component    = 0;
645     } else {
646         quant_matrix = s->chroma_intra_matrix;
647         component    = (n & 1) + 1;
648     }
649     diff = decode_dc(&s->gb, component);
650     if (diff >= 0xffff)
651         return -1;
652     dc = s->last_dc[component];
653     dc += diff;
654     s->last_dc[component] = dc;
655     block[0] = dc << (3 - s->intra_dc_precision);
656     i = 0;
657     if (s->intra_vlc_format)
658         rl = &ff_rl_mpeg2;
659     else
660         rl = &ff_rl_mpeg1;
661 
662     {
663         OPEN_READER(re, &s->gb);
664         /* now quantify & encode AC coefficients */
665         for (;;) {
666             UPDATE_CACHE(re, &s->gb);
667             GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0],
668                        TEX_VLC_BITS, 2, 0);
669 
670             if (level >= 64 || i > 63) {
671                 break;
672             } else if (level != 0) {
673                 i += run;
674                 j = scantable[i];
675                 level = (level * qscale * quant_matrix[j]) >> 4;
676                 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) -
677                         SHOW_SBITS(re, &s->gb, 1);
678                 LAST_SKIP_BITS(re, &s->gb, 1);
679             } else {
680                 /* escape */
681                 run = SHOW_UBITS(re, &s->gb, 6) + 1;
682                 LAST_SKIP_BITS(re, &s->gb, 6);
683                 UPDATE_CACHE(re, &s->gb);
684                 level = SHOW_SBITS(re, &s->gb, 12);
685                 SKIP_BITS(re, &s->gb, 12);
686                 i += run;
687                 j = scantable[i];
688                 if (level < 0) {
689                     level = (-level * qscale * quant_matrix[j]) >> 4;
690                     level = -level;
691                 } else {
692                     level = (level * qscale * quant_matrix[j]) >> 4;
693                 }
694             }
695 
696             block[j] = level;
697         }
698         CLOSE_READER(re, &s->gb);
699     }
700 
701     s->block_last_index[n] = i;
702     return 0;
703 }
704 
705 /******************************************/
706 /* decoding */
707 
get_dmv(MpegEncContext * s)708 static inline int get_dmv(MpegEncContext *s)
709 {
710     if (get_bits1(&s->gb))
711         return 1 - (get_bits1(&s->gb) << 1);
712     else
713         return 0;
714 }
715 
get_qscale(MpegEncContext * s)716 static inline int get_qscale(MpegEncContext *s)
717 {
718     int qscale = get_bits(&s->gb, 5);
719     if (s->q_scale_type)
720         return non_linear_qscale[qscale];
721     else
722         return qscale << 1;
723 }
724 
725 
726 /* motion type (for MPEG-2) */
727 #define MT_FIELD 1
728 #define MT_FRAME 2
729 #define MT_16X8  2
730 #define MT_DMV   3
731 
mpeg_decode_mb(MpegEncContext * s,int16_t block[12][64])732 static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
733 {
734     int i, j, k, cbp, val, mb_type, motion_type;
735     const int mb_block_count = 4 + (1 << s->chroma_format);
736 
737     av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
738 
739     av_assert2(s->mb_skipped == 0);
740 
741     if (s->mb_skip_run-- != 0) {
742         if (s->pict_type == AV_PICTURE_TYPE_P) {
743             s->mb_skipped = 1;
744             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
745                 MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
746         } else {
747             int mb_type;
748 
749             if (s->mb_x)
750                 mb_type = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1];
751             else
752                 // FIXME not sure if this is allowed in MPEG at all
753                 mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
754             if (IS_INTRA(mb_type)) {
755                 av_log(s->avctx, AV_LOG_ERROR, "skip with previntra\n");
756                 return -1;
757             }
758             s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
759                 mb_type | MB_TYPE_SKIP;
760 
761             if ((s->mv[0][0][0] | s->mv[0][0][1] | s->mv[1][0][0] | s->mv[1][0][1]) == 0)
762                 s->mb_skipped = 1;
763         }
764 
765         return 0;
766     }
767 
768     switch (s->pict_type) {
769     default:
770     case AV_PICTURE_TYPE_I:
771         if (get_bits1(&s->gb) == 0) {
772             if (get_bits1(&s->gb) == 0) {
773                 av_log(s->avctx, AV_LOG_ERROR,
774                        "invalid mb type in I Frame at %d %d\n",
775                        s->mb_x, s->mb_y);
776                 return -1;
777             }
778             mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
779         } else {
780             mb_type = MB_TYPE_INTRA;
781         }
782         break;
783     case AV_PICTURE_TYPE_P:
784         mb_type = get_vlc2(&s->gb, ff_mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
785         if (mb_type < 0) {
786             av_log(s->avctx, AV_LOG_ERROR,
787                    "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
788             return -1;
789         }
790         mb_type = ptype2mb_type[mb_type];
791         break;
792     case AV_PICTURE_TYPE_B:
793         mb_type = get_vlc2(&s->gb, ff_mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
794         if (mb_type < 0) {
795             av_log(s->avctx, AV_LOG_ERROR,
796                    "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
797             return -1;
798         }
799         mb_type = btype2mb_type[mb_type];
800         break;
801     }
802     av_dlog(s->avctx, "mb_type=%x\n", mb_type);
803 //    motion_type = 0; /* avoid warning */
804     if (IS_INTRA(mb_type)) {
805         s->bdsp.clear_blocks(s->block[0]);
806 
807         if (!s->chroma_y_shift)
808             s->bdsp.clear_blocks(s->block[6]);
809 
810         /* compute DCT type */
811         // FIXME: add an interlaced_dct coded var?
812         if (s->picture_structure == PICT_FRAME &&
813             !s->frame_pred_frame_dct)
814             s->interlaced_dct = get_bits1(&s->gb);
815 
816         if (IS_QUANT(mb_type))
817             s->qscale = get_qscale(s);
818 
819         if (s->concealment_motion_vectors) {
820             /* just parse them */
821             if (s->picture_structure != PICT_FRAME)
822                 skip_bits1(&s->gb);  /* field select */
823 
824             s->mv[0][0][0]      =
825             s->last_mv[0][0][0] =
826             s->last_mv[0][1][0] = mpeg_decode_motion(s, s->mpeg_f_code[0][0],
827                                                      s->last_mv[0][0][0]);
828             s->mv[0][0][1]      =
829             s->last_mv[0][0][1] =
830             s->last_mv[0][1][1] = mpeg_decode_motion(s, s->mpeg_f_code[0][1],
831                                                      s->last_mv[0][0][1]);
832 
833             skip_bits1(&s->gb); /* marker */
834         } else {
835             /* reset mv prediction */
836             memset(s->last_mv, 0, sizeof(s->last_mv));
837         }
838         s->mb_intra = 1;
839         // if 1, we memcpy blocks in xvmcvideo
840 #if (CONFIG_MPEG1_XVMC_HWACCEL == 1) || (CONFIG_MPEG2_XVMC_HWACCEL == 1)
841         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
842             ff_xvmc_pack_pblocks(s, -1); // inter are always full blocks
843 #endif
844 
845         if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
846             if (s->flags2 & CODEC_FLAG2_FAST) {
847                 for (i = 0; i < 6; i++)
848                     mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
849             } else {
850                 for (i = 0; i < mb_block_count; i++)
851                     if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0)
852                         return -1;
853             }
854         } else {
855             for (i = 0; i < 6; i++)
856                 if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0)
857                     return -1;
858         }
859     } else {
860         if (mb_type & MB_TYPE_ZERO_MV) {
861             av_assert2(mb_type & MB_TYPE_CBP);
862 
863             s->mv_dir = MV_DIR_FORWARD;
864             if (s->picture_structure == PICT_FRAME) {
865                 if (s->picture_structure == PICT_FRAME
866                     && !s->frame_pred_frame_dct)
867                     s->interlaced_dct = get_bits1(&s->gb);
868                 s->mv_type = MV_TYPE_16X16;
869             } else {
870                 s->mv_type            = MV_TYPE_FIELD;
871                 mb_type              |= MB_TYPE_INTERLACED;
872                 s->field_select[0][0] = s->picture_structure - 1;
873             }
874 
875             if (IS_QUANT(mb_type))
876                 s->qscale = get_qscale(s);
877 
878             s->last_mv[0][0][0] = 0;
879             s->last_mv[0][0][1] = 0;
880             s->last_mv[0][1][0] = 0;
881             s->last_mv[0][1][1] = 0;
882             s->mv[0][0][0]      = 0;
883             s->mv[0][0][1]      = 0;
884         } else {
885             av_assert2(mb_type & MB_TYPE_L0L1);
886             // FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
887             /* get additional motion vector type */
888             if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct) {
889                 motion_type = MT_FRAME;
890             } else {
891                 motion_type = get_bits(&s->gb, 2);
892                 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
893                     s->interlaced_dct = get_bits1(&s->gb);
894             }
895 
896             if (IS_QUANT(mb_type))
897                 s->qscale = get_qscale(s);
898 
899             /* motion vectors */
900             s->mv_dir = (mb_type >> 13) & 3;
901             av_dlog(s->avctx, "motion_type=%d\n", motion_type);
902             switch (motion_type) {
903             case MT_FRAME: /* or MT_16X8 */
904                 if (s->picture_structure == PICT_FRAME) {
905                     mb_type   |= MB_TYPE_16x16;
906                     s->mv_type = MV_TYPE_16X16;
907                     for (i = 0; i < 2; i++) {
908                         if (USES_LIST(mb_type, i)) {
909                             /* MT_FRAME */
910                             s->mv[i][0][0]      =
911                             s->last_mv[i][0][0] =
912                             s->last_mv[i][1][0] =
913                                 mpeg_decode_motion(s, s->mpeg_f_code[i][0],
914                                                    s->last_mv[i][0][0]);
915                             s->mv[i][0][1]      =
916                             s->last_mv[i][0][1] =
917                             s->last_mv[i][1][1] =
918                                 mpeg_decode_motion(s, s->mpeg_f_code[i][1],
919                                                    s->last_mv[i][0][1]);
920                             /* full_pel: only for MPEG-1 */
921                             if (s->full_pel[i]) {
922                                 s->mv[i][0][0] <<= 1;
923                                 s->mv[i][0][1] <<= 1;
924                             }
925                         }
926                     }
927                 } else {
928                     mb_type   |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
929                     s->mv_type = MV_TYPE_16X8;
930                     for (i = 0; i < 2; i++) {
931                         if (USES_LIST(mb_type, i)) {
932                             /* MT_16X8 */
933                             for (j = 0; j < 2; j++) {
934                                 s->field_select[i][j] = get_bits1(&s->gb);
935                                 for (k = 0; k < 2; k++) {
936                                     val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
937                                                              s->last_mv[i][j][k]);
938                                     s->last_mv[i][j][k] = val;
939                                     s->mv[i][j][k]      = val;
940                                 }
941                             }
942                         }
943                     }
944                 }
945                 break;
946             case MT_FIELD:
947                 s->mv_type = MV_TYPE_FIELD;
948                 if (s->picture_structure == PICT_FRAME) {
949                     mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
950                     for (i = 0; i < 2; i++) {
951                         if (USES_LIST(mb_type, i)) {
952                             for (j = 0; j < 2; j++) {
953                                 s->field_select[i][j] = get_bits1(&s->gb);
954                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
955                                                          s->last_mv[i][j][0]);
956                                 s->last_mv[i][j][0] = val;
957                                 s->mv[i][j][0]      = val;
958                                 av_dlog(s->avctx, "fmx=%d\n", val);
959                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
960                                                          s->last_mv[i][j][1] >> 1);
961                                 s->last_mv[i][j][1] = val << 1;
962                                 s->mv[i][j][1]      = val;
963                                 av_dlog(s->avctx, "fmy=%d\n", val);
964                             }
965                         }
966                     }
967                 } else {
968                     av_assert0(!s->progressive_sequence);
969                     mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
970                     for (i = 0; i < 2; i++) {
971                         if (USES_LIST(mb_type, i)) {
972                             s->field_select[i][0] = get_bits1(&s->gb);
973                             for (k = 0; k < 2; k++) {
974                                 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
975                                                          s->last_mv[i][0][k]);
976                                 s->last_mv[i][0][k] = val;
977                                 s->last_mv[i][1][k] = val;
978                                 s->mv[i][0][k]      = val;
979                             }
980                         }
981                     }
982                 }
983                 break;
984             case MT_DMV:
985                 if (s->progressive_sequence){
986                     av_log(s->avctx, AV_LOG_ERROR, "MT_DMV in progressive_sequence\n");
987                     return -1;
988                 }
989                 s->mv_type = MV_TYPE_DMV;
990                 for (i = 0; i < 2; i++) {
991                     if (USES_LIST(mb_type, i)) {
992                         int dmx, dmy, mx, my, m;
993                         const int my_shift = s->picture_structure == PICT_FRAME;
994 
995                         mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
996                                                 s->last_mv[i][0][0]);
997                         s->last_mv[i][0][0] = mx;
998                         s->last_mv[i][1][0] = mx;
999                         dmx = get_dmv(s);
1000                         my  = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
1001                                                  s->last_mv[i][0][1] >> my_shift);
1002                         dmy = get_dmv(s);
1003 
1004 
1005                         s->last_mv[i][0][1] = my << my_shift;
1006                         s->last_mv[i][1][1] = my << my_shift;
1007 
1008                         s->mv[i][0][0] = mx;
1009                         s->mv[i][0][1] = my;
1010                         s->mv[i][1][0] = mx; // not used
1011                         s->mv[i][1][1] = my; // not used
1012 
1013                         if (s->picture_structure == PICT_FRAME) {
1014                             mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
1015 
1016                             // m = 1 + 2 * s->top_field_first;
1017                             m = s->top_field_first ? 1 : 3;
1018 
1019                             /* top -> top pred */
1020                             s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1021                             s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
1022                             m = 4 - m;
1023                             s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
1024                             s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
1025                         } else {
1026                             mb_type |= MB_TYPE_16x16;
1027 
1028                             s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
1029                             s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
1030                             if (s->picture_structure == PICT_TOP_FIELD)
1031                                 s->mv[i][2][1]--;
1032                             else
1033                                 s->mv[i][2][1]++;
1034                         }
1035                     }
1036                 }
1037                 break;
1038             default:
1039                 av_log(s->avctx, AV_LOG_ERROR,
1040                        "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
1041                 return -1;
1042             }
1043         }
1044 
1045         s->mb_intra = 0;
1046         if (HAS_CBP(mb_type)) {
1047             s->bdsp.clear_blocks(s->block[0]);
1048 
1049             cbp = get_vlc2(&s->gb, ff_mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
1050             if (mb_block_count > 6) {
1051                 cbp <<= mb_block_count - 6;
1052                 cbp  |= get_bits(&s->gb, mb_block_count - 6);
1053                 s->bdsp.clear_blocks(s->block[6]);
1054             }
1055             if (cbp <= 0) {
1056                 av_log(s->avctx, AV_LOG_ERROR,
1057                        "invalid cbp %d at %d %d\n", cbp, s->mb_x, s->mb_y);
1058                 return -1;
1059             }
1060 
1061             // if 1, we memcpy blocks in xvmcvideo
1062 #if (CONFIG_MPEG1_XVMC_HWACCEL == 1) || (CONFIG_MPEG2_XVMC_HWACCEL == 1)
1063             if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1064                 ff_xvmc_pack_pblocks(s, cbp);
1065 #endif
1066 
1067             if (s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
1068                 if (s->flags2 & CODEC_FLAG2_FAST) {
1069                     for (i = 0; i < 6; i++) {
1070                         if (cbp & 32)
1071                             mpeg2_fast_decode_block_non_intra(s, *s->pblocks[i], i);
1072                         else
1073                             s->block_last_index[i] = -1;
1074                         cbp += cbp;
1075                     }
1076                 } else {
1077                     cbp <<= 12 - mb_block_count;
1078 
1079                     for (i = 0; i < mb_block_count; i++) {
1080                         if (cbp & (1 << 11)) {
1081                             if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0)
1082                                 return -1;
1083                         } else {
1084                             s->block_last_index[i] = -1;
1085                         }
1086                         cbp += cbp;
1087                     }
1088                 }
1089             } else {
1090                 if (s->flags2 & CODEC_FLAG2_FAST) {
1091                     for (i = 0; i < 6; i++) {
1092                         if (cbp & 32)
1093                             mpeg1_fast_decode_block_inter(s, *s->pblocks[i], i);
1094                         else
1095                             s->block_last_index[i] = -1;
1096                         cbp += cbp;
1097                     }
1098                 } else {
1099                     for (i = 0; i < 6; i++) {
1100                         if (cbp & 32) {
1101                             if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0)
1102                                 return -1;
1103                         } else {
1104                             s->block_last_index[i] = -1;
1105                         }
1106                         cbp += cbp;
1107                     }
1108                 }
1109             }
1110         } else {
1111             for (i = 0; i < 12; i++)
1112                 s->block_last_index[i] = -1;
1113         }
1114     }
1115 
1116     s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = mb_type;
1117 
1118     return 0;
1119 }
1120 
mpeg_decode_init(AVCodecContext * avctx)1121 static av_cold int mpeg_decode_init(AVCodecContext *avctx)
1122 {
1123     Mpeg1Context *s    = avctx->priv_data;
1124     MpegEncContext *s2 = &s->mpeg_enc_ctx;
1125 
1126     ff_mpv_decode_defaults(s2);
1127     ff_mpv_decode_init(s2, avctx);
1128 
1129     s->mpeg_enc_ctx.avctx  = avctx;
1130 
1131     /* we need some permutation to store matrices,
1132      * until the decoder sets the real permutation. */
1133     ff_mpv_idct_init(s2);
1134     ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1135     ff_mpeg12_init_vlcs();
1136 
1137     s->mpeg_enc_ctx_allocated      = 0;
1138     s->mpeg_enc_ctx.picture_number = 0;
1139     s->repeat_field                = 0;
1140     s->mpeg_enc_ctx.codec_id       = avctx->codec->id;
1141     avctx->color_range             = AVCOL_RANGE_MPEG;
1142     if (avctx->codec->id == AV_CODEC_ID_MPEG1VIDEO)
1143         avctx->chroma_sample_location = AVCHROMA_LOC_CENTER;
1144     else
1145         avctx->chroma_sample_location = AVCHROMA_LOC_LEFT;
1146     return 0;
1147 }
1148 
mpeg_decode_update_thread_context(AVCodecContext * avctx,const AVCodecContext * avctx_from)1149 static int mpeg_decode_update_thread_context(AVCodecContext *avctx,
1150                                              const AVCodecContext *avctx_from)
1151 {
1152     Mpeg1Context *ctx = avctx->priv_data, *ctx_from = avctx_from->priv_data;
1153     MpegEncContext *s = &ctx->mpeg_enc_ctx, *s1 = &ctx_from->mpeg_enc_ctx;
1154     int err;
1155 
1156     if (avctx == avctx_from               ||
1157         !ctx_from->mpeg_enc_ctx_allocated ||
1158         !s1->context_initialized)
1159         return 0;
1160 
1161     err = ff_mpeg_update_thread_context(avctx, avctx_from);
1162     if (err)
1163         return err;
1164 
1165     if (!ctx->mpeg_enc_ctx_allocated)
1166         memcpy(s + 1, s1 + 1, sizeof(Mpeg1Context) - sizeof(MpegEncContext));
1167 
1168     if (!(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay))
1169         s->picture_number++;
1170 
1171     return 0;
1172 }
1173 
quant_matrix_rebuild(uint16_t * matrix,const uint8_t * old_perm,const uint8_t * new_perm)1174 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1175                                  const uint8_t *new_perm)
1176 {
1177     uint16_t temp_matrix[64];
1178     int i;
1179 
1180     memcpy(temp_matrix, matrix, 64 * sizeof(uint16_t));
1181 
1182     for (i = 0; i < 64; i++)
1183         matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1184 }
1185 
1186 static const enum AVPixelFormat mpeg1_hwaccel_pixfmt_list_420[] = {
1187 #if CONFIG_MPEG1_XVMC_HWACCEL
1188     AV_PIX_FMT_XVMC,
1189 #endif
1190 #if CONFIG_MPEG1_VDPAU_HWACCEL
1191     AV_PIX_FMT_VDPAU_MPEG1,
1192     AV_PIX_FMT_VDPAU,
1193 #endif
1194     AV_PIX_FMT_YUV420P,
1195     AV_PIX_FMT_NONE
1196 };
1197 
1198 static const enum AVPixelFormat mpeg2_hwaccel_pixfmt_list_420[] = {
1199 #if CONFIG_MPEG2_XVMC_HWACCEL
1200     AV_PIX_FMT_XVMC,
1201 #endif
1202 #if CONFIG_MPEG2_VDPAU_HWACCEL
1203     AV_PIX_FMT_VDPAU_MPEG2,
1204     AV_PIX_FMT_VDPAU,
1205 #endif
1206 #if CONFIG_MPEG2_DXVA2_HWACCEL
1207     AV_PIX_FMT_DXVA2_VLD,
1208 #endif
1209 #if CONFIG_MPEG2_VAAPI_HWACCEL
1210     AV_PIX_FMT_VAAPI_VLD,
1211 #endif
1212     AV_PIX_FMT_YUV420P,
1213     AV_PIX_FMT_NONE
1214 };
1215 
1216 static const enum AVPixelFormat mpeg12_pixfmt_list_422[] = {
1217     AV_PIX_FMT_YUV422P,
1218     AV_PIX_FMT_NONE
1219 };
1220 
1221 static const enum AVPixelFormat mpeg12_pixfmt_list_444[] = {
1222     AV_PIX_FMT_YUV444P,
1223     AV_PIX_FMT_NONE
1224 };
1225 
uses_vdpau(AVCodecContext * avctx)1226 static inline int uses_vdpau(AVCodecContext *avctx) {
1227     return avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG1 || avctx->pix_fmt == AV_PIX_FMT_VDPAU_MPEG2;
1228 }
1229 
mpeg_get_pixelformat(AVCodecContext * avctx)1230 static enum AVPixelFormat mpeg_get_pixelformat(AVCodecContext *avctx)
1231 {
1232     Mpeg1Context *s1  = avctx->priv_data;
1233     MpegEncContext *s = &s1->mpeg_enc_ctx;
1234     const enum AVPixelFormat *pix_fmts;
1235 
1236     if (s->chroma_format < 2)
1237         pix_fmts = avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO ?
1238                                 mpeg1_hwaccel_pixfmt_list_420 :
1239                                 mpeg2_hwaccel_pixfmt_list_420;
1240     else if (s->chroma_format == 2)
1241         pix_fmts = mpeg12_pixfmt_list_422;
1242     else
1243         pix_fmts = mpeg12_pixfmt_list_444;
1244 
1245     return ff_thread_get_format(avctx, pix_fmts);
1246 }
1247 
setup_hwaccel_for_pixfmt(AVCodecContext * avctx)1248 static void setup_hwaccel_for_pixfmt(AVCodecContext *avctx)
1249 {
1250     // until then pix_fmt may be changed right after codec init
1251     if (avctx->hwaccel || uses_vdpau(avctx))
1252         if (avctx->idct_algo == FF_IDCT_AUTO)
1253             avctx->idct_algo = FF_IDCT_SIMPLE;
1254 
1255     if (avctx->hwaccel && avctx->pix_fmt == AV_PIX_FMT_XVMC) {
1256         Mpeg1Context *s1 = avctx->priv_data;
1257         MpegEncContext *s = &s1->mpeg_enc_ctx;
1258 
1259         s->pack_pblocks = 1;
1260 #if FF_API_XVMC
1261         avctx->xvmc_acceleration = 2;
1262 #endif /* FF_API_XVMC */
1263     }
1264 }
1265 
1266 /* Call this function when we know all parameters.
1267  * It may be called in different places for MPEG-1 and MPEG-2. */
mpeg_decode_postinit(AVCodecContext * avctx)1268 static int mpeg_decode_postinit(AVCodecContext *avctx)
1269 {
1270     Mpeg1Context *s1  = avctx->priv_data;
1271     MpegEncContext *s = &s1->mpeg_enc_ctx;
1272     uint8_t old_permutation[64];
1273     int ret;
1274 
1275     if ((s1->mpeg_enc_ctx_allocated == 0)                   ||
1276         avctx->coded_width       != s->width                ||
1277         avctx->coded_height      != s->height               ||
1278         s1->save_width           != s->width                ||
1279         s1->save_height          != s->height               ||
1280         s1->save_aspect_info     != s->aspect_ratio_info    ||
1281         (s1->save_progressive_seq != s->progressive_sequence && FFALIGN(s->height, 16) != FFALIGN(s->height, 32)) ||
1282         0) {
1283         if (s1->mpeg_enc_ctx_allocated) {
1284             ParseContext pc = s->parse_context;
1285             s->parse_context.buffer = 0;
1286             ff_mpv_common_end(s);
1287             s->parse_context = pc;
1288             s1->mpeg_enc_ctx_allocated = 0;
1289         }
1290 
1291         if ((s->width == 0) || (s->height == 0))
1292             return -2;
1293 
1294         ret = ff_set_dimensions(avctx, s->width, s->height);
1295         if (ret < 0)
1296             return ret;
1297 
1298         if (avctx->codec_id == AV_CODEC_ID_MPEG2VIDEO && s->bit_rate) {
1299             avctx->rc_max_rate = s->bit_rate;
1300         } else if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO && s->bit_rate &&
1301                    (s->bit_rate != 0x3FFFF*400 || s->vbv_delay != 0xFFFF)) {
1302             avctx->bit_rate = s->bit_rate;
1303         }
1304         s1->save_aspect_info     = s->aspect_ratio_info;
1305         s1->save_width           = s->width;
1306         s1->save_height          = s->height;
1307         s1->save_progressive_seq = s->progressive_sequence;
1308 
1309         /* low_delay may be forced, in this case we will have B-frames
1310          * that behave like P-frames. */
1311         avctx->has_b_frames = !s->low_delay;
1312 
1313         if (avctx->codec_id == AV_CODEC_ID_MPEG1VIDEO) {
1314             // MPEG-1 fps
1315             avctx->time_base.den = ff_mpeg12_frame_rate_tab[s->frame_rate_index].num;
1316             avctx->time_base.num = ff_mpeg12_frame_rate_tab[s->frame_rate_index].den;
1317             // MPEG-1 aspect
1318             avctx->sample_aspect_ratio = av_d2q(1.0 / ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1319             avctx->ticks_per_frame     = 1;
1320         } else { // MPEG-2
1321             // MPEG-2 fps
1322             av_reduce(&s->avctx->time_base.den,
1323                       &s->avctx->time_base.num,
1324                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num * 2,
1325                       ff_mpeg12_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1326                       1 << 30);
1327             avctx->ticks_per_frame = 2;
1328             // MPEG-2 aspect
1329             if (s->aspect_ratio_info > 1) {
1330 				AVRational dar =
1331                     av_mul_q(av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1332                                       (AVRational) { s1->pan_scan.width,
1333                                                      s1->pan_scan.height }),
1334                              (AVRational) { s->width, s->height });
1335 
1336                 /* We ignore the spec here and guess a bit as reality does not
1337                  * match the spec, see for example res_change_ffmpeg_aspect.ts
1338                  * and sequence-display-aspect.mpg.
1339                  * issue1613, 621, 562 */
1340 				if ((s1->pan_scan.width == 0) || (s1->pan_scan.height == 0) ||
1341                     (av_cmp_q(dar, (AVRational) { 4, 3 }) &&
1342                      av_cmp_q(dar, (AVRational) { 16, 9 }))) {
1343                     s->avctx->sample_aspect_ratio =
1344                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1345                                  (AVRational) { s->width, s->height });
1346                 } else {
1347                     s->avctx->sample_aspect_ratio =
1348                         av_div_q(ff_mpeg2_aspect[s->aspect_ratio_info],
1349                                  (AVRational) { s1->pan_scan.width, s1->pan_scan.height });
1350 // issue1613 4/3 16/9 -> 16/9
1351 // res_change_ffmpeg_aspect.ts 4/3 225/44 ->4/3
1352 // widescreen-issue562.mpg 4/3 16/9 -> 16/9
1353 //                    s->avctx->sample_aspect_ratio = av_mul_q(s->avctx->sample_aspect_ratio, (AVRational) {s->width, s->height});
1354                     av_dlog(avctx, "A %d/%d\n",
1355                             ff_mpeg2_aspect[s->aspect_ratio_info].num,
1356                             ff_mpeg2_aspect[s->aspect_ratio_info].den);
1357                     av_dlog(avctx, "B %d/%d\n", s->avctx->sample_aspect_ratio.num,
1358                             s->avctx->sample_aspect_ratio.den);
1359                 }
1360             } else {
1361                 s->avctx->sample_aspect_ratio =
1362                     ff_mpeg2_aspect[s->aspect_ratio_info];
1363             }
1364         } // MPEG-2
1365 
1366         ff_set_sar(s->avctx, s->avctx->sample_aspect_ratio);
1367 
1368         avctx->pix_fmt = mpeg_get_pixelformat(avctx);
1369         setup_hwaccel_for_pixfmt(avctx);
1370 
1371         /* Quantization matrices may need reordering
1372          * if DCT permutation is changed. */
1373         memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
1374 
1375         ff_mpv_idct_init(s);
1376         if (ff_mpv_common_init(s) < 0)
1377             return -2;
1378 
1379         quant_matrix_rebuild(s->intra_matrix,        old_permutation, s->idsp.idct_permutation);
1380         quant_matrix_rebuild(s->inter_matrix,        old_permutation, s->idsp.idct_permutation);
1381         quant_matrix_rebuild(s->chroma_intra_matrix, old_permutation, s->idsp.idct_permutation);
1382         quant_matrix_rebuild(s->chroma_inter_matrix, old_permutation, s->idsp.idct_permutation);
1383 
1384         s1->mpeg_enc_ctx_allocated = 1;
1385     }
1386     return 0;
1387 }
1388 
mpeg1_decode_picture(AVCodecContext * avctx,const uint8_t * buf,int buf_size)1389 static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
1390                                 int buf_size)
1391 {
1392     Mpeg1Context *s1  = avctx->priv_data;
1393     MpegEncContext *s = &s1->mpeg_enc_ctx;
1394     int ref, f_code, vbv_delay;
1395 
1396     init_get_bits(&s->gb, buf, buf_size * 8);
1397 
1398     ref = get_bits(&s->gb, 10); /* temporal ref */
1399     s->pict_type = get_bits(&s->gb, 3);
1400     if (s->pict_type == 0 || s->pict_type > 3)
1401         return -1;
1402 
1403     vbv_delay = get_bits(&s->gb, 16);
1404     s->vbv_delay = vbv_delay;
1405     if (s->pict_type == AV_PICTURE_TYPE_P ||
1406         s->pict_type == AV_PICTURE_TYPE_B) {
1407         s->full_pel[0] = get_bits1(&s->gb);
1408         f_code = get_bits(&s->gb, 3);
1409         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1410             return -1;
1411         f_code += !f_code;
1412         s->mpeg_f_code[0][0] = f_code;
1413         s->mpeg_f_code[0][1] = f_code;
1414     }
1415     if (s->pict_type == AV_PICTURE_TYPE_B) {
1416         s->full_pel[1] = get_bits1(&s->gb);
1417         f_code = get_bits(&s->gb, 3);
1418         if (f_code == 0 && (avctx->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT)))
1419             return -1;
1420         f_code += !f_code;
1421         s->mpeg_f_code[1][0] = f_code;
1422         s->mpeg_f_code[1][1] = f_code;
1423     }
1424     s->current_picture.f->pict_type = s->pict_type;
1425     s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1426 
1427     if (avctx->debug & FF_DEBUG_PICT_INFO)
1428         av_log(avctx, AV_LOG_DEBUG,
1429                "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1430 
1431     s->y_dc_scale = 8;
1432     s->c_dc_scale = 8;
1433     return 0;
1434 }
1435 
mpeg_decode_sequence_extension(Mpeg1Context * s1)1436 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1437 {
1438     MpegEncContext *s = &s1->mpeg_enc_ctx;
1439     int horiz_size_ext, vert_size_ext;
1440     int bit_rate_ext;
1441 
1442     skip_bits(&s->gb, 1); /* profile and level esc*/
1443     s->avctx->profile       = get_bits(&s->gb, 3);
1444     s->avctx->level         = get_bits(&s->gb, 4);
1445     s->progressive_sequence = get_bits1(&s->gb);   /* progressive_sequence */
1446     s->chroma_format        = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1447     horiz_size_ext          = get_bits(&s->gb, 2);
1448     vert_size_ext           = get_bits(&s->gb, 2);
1449     s->width  |= (horiz_size_ext << 12);
1450     s->height |= (vert_size_ext  << 12);
1451     bit_rate_ext = get_bits(&s->gb, 12);  /* XXX: handle it */
1452     s->bit_rate += (bit_rate_ext << 18) * 400;
1453     skip_bits1(&s->gb); /* marker */
1454     s->avctx->rc_buffer_size += get_bits(&s->gb, 8) * 1024 * 16 << 10;
1455 
1456     s->low_delay = get_bits1(&s->gb);
1457     if (s->flags & CODEC_FLAG_LOW_DELAY)
1458         s->low_delay = 1;
1459 
1460     s1->frame_rate_ext.num = get_bits(&s->gb, 2) + 1;
1461     s1->frame_rate_ext.den = get_bits(&s->gb, 5) + 1;
1462 
1463     av_dlog(s->avctx, "sequence extension\n");
1464     s->codec_id = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
1465 
1466     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1467         av_log(s->avctx, AV_LOG_DEBUG,
1468                "profile: %d, level: %d ps: %d cf:%d vbv buffer: %d, bitrate:%d\n",
1469                s->avctx->profile, s->avctx->level, s->progressive_sequence, s->chroma_format,
1470                s->avctx->rc_buffer_size, s->bit_rate);
1471 }
1472 
mpeg_decode_sequence_display_extension(Mpeg1Context * s1)1473 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1474 {
1475     MpegEncContext *s = &s1->mpeg_enc_ctx;
1476     int color_description, w, h;
1477 
1478     skip_bits(&s->gb, 3); /* video format */
1479     color_description = get_bits1(&s->gb);
1480     if (color_description) {
1481         s->avctx->color_primaries = get_bits(&s->gb, 8);
1482         s->avctx->color_trc       = get_bits(&s->gb, 8);
1483         s->avctx->colorspace      = get_bits(&s->gb, 8);
1484     }
1485     w = get_bits(&s->gb, 14);
1486     skip_bits(&s->gb, 1); // marker
1487     h = get_bits(&s->gb, 14);
1488     // remaining 3 bits are zero padding
1489 
1490     s1->pan_scan.width  = 16 * w;
1491     s1->pan_scan.height = 16 * h;
1492 
1493     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1494         av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1495 }
1496 
mpeg_decode_picture_display_extension(Mpeg1Context * s1)1497 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1498 {
1499     MpegEncContext *s = &s1->mpeg_enc_ctx;
1500     int i, nofco;
1501 
1502     nofco = 1;
1503     if (s->progressive_sequence) {
1504         if (s->repeat_first_field) {
1505             nofco++;
1506             if (s->top_field_first)
1507                 nofco++;
1508         }
1509     } else {
1510         if (s->picture_structure == PICT_FRAME) {
1511             nofco++;
1512             if (s->repeat_first_field)
1513                 nofco++;
1514         }
1515     }
1516     for (i = 0; i < nofco; i++) {
1517         s1->pan_scan.position[i][0] = get_sbits(&s->gb, 16);
1518         skip_bits(&s->gb, 1); // marker
1519         s1->pan_scan.position[i][1] = get_sbits(&s->gb, 16);
1520         skip_bits(&s->gb, 1); // marker
1521     }
1522 
1523     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
1524         av_log(s->avctx, AV_LOG_DEBUG,
1525                "pde (%"PRId16",%"PRId16") (%"PRId16",%"PRId16") (%"PRId16",%"PRId16")\n",
1526                s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1527                s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1528                s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]);
1529 }
1530 
load_matrix(MpegEncContext * s,uint16_t matrix0[64],uint16_t matrix1[64],int intra)1531 static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
1532                        uint16_t matrix1[64], int intra)
1533 {
1534     int i;
1535 
1536     for (i = 0; i < 64; i++) {
1537         int j = s->idsp.idct_permutation[ff_zigzag_direct[i]];
1538         int v = get_bits(&s->gb, 8);
1539         if (v == 0) {
1540             av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
1541             return -1;
1542         }
1543         if (intra && i == 0 && v != 8) {
1544             av_log(s->avctx, AV_LOG_DEBUG, "intra matrix specifies invalid DC quantizer %d, ignoring\n", v);
1545             v = 8; // needed by pink.mpg / issue1046
1546         }
1547         matrix0[j] = v;
1548         if (matrix1)
1549             matrix1[j] = v;
1550     }
1551     return 0;
1552 }
1553 
mpeg_decode_quant_matrix_extension(MpegEncContext * s)1554 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1555 {
1556     av_dlog(s->avctx, "matrix extension\n");
1557 
1558     if (get_bits1(&s->gb))
1559         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
1560     if (get_bits1(&s->gb))
1561         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
1562     if (get_bits1(&s->gb))
1563         load_matrix(s, s->chroma_intra_matrix, NULL, 1);
1564     if (get_bits1(&s->gb))
1565         load_matrix(s, s->chroma_inter_matrix, NULL, 0);
1566 }
1567 
mpeg_decode_picture_coding_extension(Mpeg1Context * s1)1568 static void mpeg_decode_picture_coding_extension(Mpeg1Context *s1)
1569 {
1570     MpegEncContext *s = &s1->mpeg_enc_ctx;
1571 
1572     s->full_pel[0]       = s->full_pel[1] = 0;
1573     s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1574     s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1575     s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1576     s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1577     if (!s->pict_type && s1->mpeg_enc_ctx_allocated) {
1578         av_log(s->avctx, AV_LOG_ERROR,
1579                "Missing picture start code, guessing missing values\n");
1580         if (s->mpeg_f_code[1][0] == 15 && s->mpeg_f_code[1][1] == 15) {
1581             if (s->mpeg_f_code[0][0] == 15 && s->mpeg_f_code[0][1] == 15)
1582                 s->pict_type = AV_PICTURE_TYPE_I;
1583             else
1584                 s->pict_type = AV_PICTURE_TYPE_P;
1585         } else
1586             s->pict_type = AV_PICTURE_TYPE_B;
1587         s->current_picture.f->pict_type = s->pict_type;
1588         s->current_picture.f->key_frame = s->pict_type == AV_PICTURE_TYPE_I;
1589     }
1590     s->mpeg_f_code[0][0] += !s->mpeg_f_code[0][0];
1591     s->mpeg_f_code[0][1] += !s->mpeg_f_code[0][1];
1592     s->mpeg_f_code[1][0] += !s->mpeg_f_code[1][0];
1593     s->mpeg_f_code[1][1] += !s->mpeg_f_code[1][1];
1594 
1595     s->intra_dc_precision         = get_bits(&s->gb, 2);
1596     s->picture_structure          = get_bits(&s->gb, 2);
1597     s->top_field_first            = get_bits1(&s->gb);
1598     s->frame_pred_frame_dct       = get_bits1(&s->gb);
1599     s->concealment_motion_vectors = get_bits1(&s->gb);
1600     s->q_scale_type               = get_bits1(&s->gb);
1601     s->intra_vlc_format           = get_bits1(&s->gb);
1602     s->alternate_scan             = get_bits1(&s->gb);
1603     s->repeat_first_field         = get_bits1(&s->gb);
1604     s->chroma_420_type            = get_bits1(&s->gb);
1605     s->progressive_frame          = get_bits1(&s->gb);
1606 
1607     if (s->alternate_scan) {
1608         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_alternate_vertical_scan);
1609         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_alternate_vertical_scan);
1610     } else {
1611         ff_init_scantable(s->idsp.idct_permutation, &s->inter_scantable, ff_zigzag_direct);
1612         ff_init_scantable(s->idsp.idct_permutation, &s->intra_scantable, ff_zigzag_direct);
1613     }
1614 
1615     /* composite display not parsed */
1616     av_dlog(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1617     av_dlog(s->avctx, "picture_structure=%d\n", s->picture_structure);
1618     av_dlog(s->avctx, "top field first=%d\n", s->top_field_first);
1619     av_dlog(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1620     av_dlog(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1621     av_dlog(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1622     av_dlog(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1623     av_dlog(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1624     av_dlog(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1625 }
1626 
mpeg_field_start(MpegEncContext * s,const uint8_t * buf,int buf_size)1627 static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
1628 {
1629     AVCodecContext *avctx = s->avctx;
1630     Mpeg1Context *s1      = (Mpeg1Context *) s;
1631 
1632     /* start frame decoding */
1633     if (s->first_field || s->picture_structure == PICT_FRAME) {
1634         AVFrameSideData *pan_scan;
1635 
1636         if (ff_mpv_frame_start(s, avctx) < 0)
1637             return -1;
1638 
1639         ff_mpeg_er_frame_start(s);
1640 
1641         /* first check if we must repeat the frame */
1642         s->current_picture_ptr->f->repeat_pict = 0;
1643         if (s->repeat_first_field) {
1644             if (s->progressive_sequence) {
1645                 if (s->top_field_first)
1646                     s->current_picture_ptr->f->repeat_pict = 4;
1647                 else
1648                     s->current_picture_ptr->f->repeat_pict = 2;
1649             } else if (s->progressive_frame) {
1650                 s->current_picture_ptr->f->repeat_pict = 1;
1651             }
1652         }
1653 
1654         pan_scan = av_frame_new_side_data(s->current_picture_ptr->f,
1655                                           AV_FRAME_DATA_PANSCAN,
1656                                           sizeof(s1->pan_scan));
1657         if (!pan_scan)
1658             return AVERROR(ENOMEM);
1659         memcpy(pan_scan->data, &s1->pan_scan, sizeof(s1->pan_scan));
1660 
1661         if (s1->a53_caption) {
1662             AVFrameSideData *sd = av_frame_new_side_data(
1663                 s->current_picture_ptr->f, AV_FRAME_DATA_A53_CC,
1664                 s1->a53_caption_size);
1665             if (sd)
1666                 memcpy(sd->data, s1->a53_caption, s1->a53_caption_size);
1667             av_freep(&s1->a53_caption);
1668         }
1669 
1670         if (s1->has_stereo3d) {
1671             AVStereo3D *stereo = av_stereo3d_create_side_data(s->current_picture_ptr->f);
1672             if (!stereo)
1673                 return AVERROR(ENOMEM);
1674 
1675             *stereo = s1->stereo3d;
1676             s1->has_stereo3d = 0;
1677         }
1678 
1679         if (s1->has_afd) {
1680             AVFrameSideData *sd =
1681                 av_frame_new_side_data(s->current_picture_ptr->f,
1682                                        AV_FRAME_DATA_AFD, 1);
1683             if (!sd)
1684                 return AVERROR(ENOMEM);
1685 
1686             *sd->data   = s1->afd;
1687             s1->has_afd = 0;
1688         }
1689 
1690         if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_FRAME))
1691             ff_thread_finish_setup(avctx);
1692     } else { // second field
1693         int i;
1694 
1695         if (!s->current_picture_ptr) {
1696             av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1697             return -1;
1698         }
1699 
1700         if (s->avctx->hwaccel &&
1701             (s->avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
1702             if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
1703                 av_log(avctx, AV_LOG_ERROR,
1704                        "hardware accelerator failed to decode first field\n");
1705         }
1706 
1707         for (i = 0; i < 4; i++) {
1708             s->current_picture.f->data[i] = s->current_picture_ptr->f->data[i];
1709             if (s->picture_structure == PICT_BOTTOM_FIELD)
1710                 s->current_picture.f->data[i] +=
1711                     s->current_picture_ptr->f->linesize[i];
1712         }
1713     }
1714 
1715     if (avctx->hwaccel) {
1716         if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0)
1717             return -1;
1718     }
1719 
1720     return 0;
1721 }
1722 
1723 #define DECODE_SLICE_ERROR -1
1724 #define DECODE_SLICE_OK     0
1725 
1726 /**
1727  * Decode a slice.
1728  * MpegEncContext.mb_y must be set to the MB row from the startcode.
1729  * @return DECODE_SLICE_ERROR if the slice is damaged,
1730  *         DECODE_SLICE_OK if this slice is OK
1731  */
mpeg_decode_slice(MpegEncContext * s,int mb_y,const uint8_t ** buf,int buf_size)1732 static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
1733                              const uint8_t **buf, int buf_size)
1734 {
1735     AVCodecContext *avctx = s->avctx;
1736     const int lowres      = s->avctx->lowres;
1737     const int field_pic   = s->picture_structure != PICT_FRAME;
1738 
1739     s->resync_mb_x =
1740     s->resync_mb_y = -1;
1741 
1742     av_assert0(mb_y < s->mb_height);
1743 
1744     init_get_bits(&s->gb, *buf, buf_size * 8);
1745     if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
1746         skip_bits(&s->gb, 3);
1747 
1748     ff_mpeg1_clean_buffers(s);
1749     s->interlaced_dct = 0;
1750 
1751     s->qscale = get_qscale(s);
1752 
1753     if (s->qscale == 0) {
1754         av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1755         return -1;
1756     }
1757 
1758     /* extra slice info */
1759     if (skip_1stop_8data_bits(&s->gb) < 0)
1760         return AVERROR_INVALIDDATA;
1761 
1762     s->mb_x = 0;
1763 
1764     if (mb_y == 0 && s->codec_tag == AV_RL32("SLIF")) {
1765         skip_bits1(&s->gb);
1766     } else {
1767         while (get_bits_left(&s->gb) > 0) {
1768             int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1769                                 MBINCR_VLC_BITS, 2);
1770             if (code < 0) {
1771                 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1772                 return -1;
1773             }
1774             if (code >= 33) {
1775                 if (code == 33)
1776                     s->mb_x += 33;
1777                 /* otherwise, stuffing, nothing to do */
1778             } else {
1779                 s->mb_x += code;
1780                 break;
1781             }
1782         }
1783     }
1784 
1785     if (s->mb_x >= (unsigned) s->mb_width) {
1786         av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1787         return -1;
1788     }
1789 
1790     if (avctx->hwaccel && avctx->hwaccel->decode_slice) {
1791         const uint8_t *buf_end, *buf_start = *buf - 4; /* include start_code */
1792         int start_code = -1;
1793         buf_end = avpriv_find_start_code(buf_start + 2, *buf + buf_size, &start_code);
1794         if (buf_end < *buf + buf_size)
1795             buf_end -= 4;
1796         s->mb_y = mb_y;
1797         if (avctx->hwaccel->decode_slice(avctx, buf_start, buf_end - buf_start) < 0)
1798             return DECODE_SLICE_ERROR;
1799         *buf = buf_end;
1800         return DECODE_SLICE_OK;
1801     }
1802 
1803     s->resync_mb_x = s->mb_x;
1804     s->resync_mb_y = s->mb_y = mb_y;
1805     s->mb_skip_run = 0;
1806     ff_init_block_index(s);
1807 
1808     if (s->mb_y == 0 && s->mb_x == 0 && (s->first_field || s->picture_structure == PICT_FRAME)) {
1809         if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
1810             av_log(s->avctx, AV_LOG_DEBUG,
1811                    "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",
1812                    s->qscale,
1813                    s->mpeg_f_code[0][0], s->mpeg_f_code[0][1],
1814                    s->mpeg_f_code[1][0], s->mpeg_f_code[1][1],
1815                    s->pict_type  == AV_PICTURE_TYPE_I ? "I" :
1816                    (s->pict_type == AV_PICTURE_TYPE_P ? "P" :
1817                    (s->pict_type == AV_PICTURE_TYPE_B ? "B" : "S")),
1818                    s->progressive_sequence ? "ps"  : "",
1819                    s->progressive_frame    ? "pf"  : "",
1820                    s->alternate_scan       ? "alt" : "",
1821                    s->top_field_first      ? "top" : "",
1822                    s->intra_dc_precision, s->picture_structure,
1823                    s->frame_pred_frame_dct, s->concealment_motion_vectors,
1824                    s->q_scale_type, s->intra_vlc_format,
1825                    s->repeat_first_field, s->chroma_420_type ? "420" : "");
1826         }
1827     }
1828 
1829     for (;;) {
1830         // If 1, we memcpy blocks in xvmcvideo.
1831 #if (CONFIG_MPEG1_XVMC_HWACCEL == 1) || (CONFIG_MPEG2_XVMC_HWACCEL == 1)
1832         if ((CONFIG_MPEG1_XVMC_HWACCEL || CONFIG_MPEG2_XVMC_HWACCEL) && s->pack_pblocks)
1833             ff_xvmc_init_block(s); // set s->block
1834 #endif
1835 
1836         if (mpeg_decode_mb(s, s->block) < 0)
1837             return -1;
1838 
1839         // Note motion_val is normally NULL unless we want to extract the MVs.
1840         if (s->current_picture.motion_val[0] && !s->encoding) {
1841             const int wrap = s->b8_stride;
1842             int xy         = s->mb_x * 2 + s->mb_y * 2 * wrap;
1843             int b8_xy      = 4 * (s->mb_x + s->mb_y * s->mb_stride);
1844             int motion_x, motion_y, dir, i;
1845 
1846             for (i = 0; i < 2; i++) {
1847                 for (dir = 0; dir < 2; dir++) {
1848                     if (s->mb_intra ||
1849                         (dir == 1 && s->pict_type != AV_PICTURE_TYPE_B)) {
1850                         motion_x = motion_y = 0;
1851                     } else if (s->mv_type == MV_TYPE_16X16 ||
1852                                (s->mv_type == MV_TYPE_FIELD && field_pic)) {
1853                         motion_x = s->mv[dir][0][0];
1854                         motion_y = s->mv[dir][0][1];
1855                     } else { /* if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8)) */
1856                         motion_x = s->mv[dir][i][0];
1857                         motion_y = s->mv[dir][i][1];
1858                     }
1859 
1860                     s->current_picture.motion_val[dir][xy][0]     = motion_x;
1861                     s->current_picture.motion_val[dir][xy][1]     = motion_y;
1862                     s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1863                     s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1864                     s->current_picture.ref_index [dir][b8_xy]     =
1865                     s->current_picture.ref_index [dir][b8_xy + 1] = s->field_select[dir][i];
1866                     av_assert2(s->field_select[dir][i] == 0 ||
1867                                s->field_select[dir][i] == 1);
1868                 }
1869                 xy    += wrap;
1870                 b8_xy += 2;
1871             }
1872         }
1873 
1874         s->dest[0] += 16 >> lowres;
1875         s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1876         s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1877 
1878         ff_mpv_decode_mb(s, s->block);
1879 
1880         if (++s->mb_x >= s->mb_width) {
1881             const int mb_size = 16 >> s->avctx->lowres;
1882 
1883             ff_mpeg_draw_horiz_band(s, mb_size * (s->mb_y >> field_pic), mb_size);
1884             ff_mpv_report_decode_progress(s);
1885 
1886             s->mb_x  = 0;
1887             s->mb_y += 1 << field_pic;
1888 
1889             if (s->mb_y >= s->mb_height) {
1890                 int left   = get_bits_left(&s->gb);
1891                 int is_d10 = s->chroma_format == 2 &&
1892                              s->pict_type == AV_PICTURE_TYPE_I &&
1893                              avctx->profile == 0 && avctx->level == 5 &&
1894                              s->intra_dc_precision == 2 &&
1895                              s->q_scale_type == 1 && s->alternate_scan == 0 &&
1896                              s->progressive_frame == 0
1897                              /* vbv_delay == 0xBBB || 0xE10 */;
1898 
1899                 if (left >= 32 && !is_d10) {
1900                     GetBitContext gb = s->gb;
1901                     align_get_bits(&gb);
1902                     if (show_bits(&gb, 24) == 0x060E2B) {
1903                         av_log(avctx, AV_LOG_DEBUG, "Invalid MXF data found in video stream\n");
1904                         is_d10 = 1;
1905                     }
1906                 }
1907 
1908                 if (left < 0 ||
1909                     (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10) ||
1910                     ((avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_AGGRESSIVE)) && left > 8)) {
1911                     av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
1912                            left, show_bits(&s->gb, FFMIN(left, 23)));
1913                     return -1;
1914                 } else
1915                     goto eos;
1916             }
1917             // There are some files out there which are missing the last slice
1918             // in cases where the slice is completely outside the visible
1919             // area, we detect this here instead of running into the end expecting
1920             // more data
1921             if (s->mb_y >= ((s->height + 15) >> 4) &&
1922                 s->progressive_frame &&
1923                 !s->progressive_sequence &&
1924                 get_bits_left(&s->gb) <= 8 &&
1925                 get_bits_left(&s->gb) >= 0 &&
1926                 s->mb_skip_run == -1 &&
1927                 show_bits(&s->gb, 8) == 0)
1928                 goto eos;
1929 
1930             ff_init_block_index(s);
1931         }
1932 
1933         /* skip mb handling */
1934         if (s->mb_skip_run == -1) {
1935             /* read increment again */
1936             s->mb_skip_run = 0;
1937             for (;;) {
1938                 int code = get_vlc2(&s->gb, ff_mbincr_vlc.table,
1939                                     MBINCR_VLC_BITS, 2);
1940                 if (code < 0) {
1941                     av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1942                     return -1;
1943                 }
1944                 if (code >= 33) {
1945                     if (code == 33) {
1946                         s->mb_skip_run += 33;
1947                     } else if (code == 35) {
1948                         if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
1949                             av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1950                             return -1;
1951                         }
1952                         goto eos; /* end of slice */
1953                     }
1954                     /* otherwise, stuffing, nothing to do */
1955                 } else {
1956                     s->mb_skip_run += code;
1957                     break;
1958                 }
1959             }
1960             if (s->mb_skip_run) {
1961                 int i;
1962                 if (s->pict_type == AV_PICTURE_TYPE_I) {
1963                     av_log(s->avctx, AV_LOG_ERROR,
1964                            "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1965                     return -1;
1966                 }
1967 
1968                 /* skip mb */
1969                 s->mb_intra = 0;
1970                 for (i = 0; i < 12; i++)
1971                     s->block_last_index[i] = -1;
1972                 if (s->picture_structure == PICT_FRAME)
1973                     s->mv_type = MV_TYPE_16X16;
1974                 else
1975                     s->mv_type = MV_TYPE_FIELD;
1976                 if (s->pict_type == AV_PICTURE_TYPE_P) {
1977                     /* if P type, zero motion vector is implied */
1978                     s->mv_dir             = MV_DIR_FORWARD;
1979                     s->mv[0][0][0]        = s->mv[0][0][1]      = 0;
1980                     s->last_mv[0][0][0]   = s->last_mv[0][0][1] = 0;
1981                     s->last_mv[0][1][0]   = s->last_mv[0][1][1] = 0;
1982                     s->field_select[0][0] = (s->picture_structure - 1) & 1;
1983                 } else {
1984                     /* if B type, reuse previous vectors and directions */
1985                     s->mv[0][0][0] = s->last_mv[0][0][0];
1986                     s->mv[0][0][1] = s->last_mv[0][0][1];
1987                     s->mv[1][0][0] = s->last_mv[1][0][0];
1988                     s->mv[1][0][1] = s->last_mv[1][0][1];
1989                 }
1990             }
1991         }
1992     }
1993 eos: // end of slice
1994     if (get_bits_left(&s->gb) < 0) {
1995         av_log(s, AV_LOG_ERROR, "overread %d\n", -get_bits_left(&s->gb));
1996         return AVERROR_INVALIDDATA;
1997     }
1998     *buf += (get_bits_count(&s->gb) - 1) / 8;
1999     av_dlog(s, "y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
2000     return 0;
2001 }
2002 
slice_decode_thread(AVCodecContext * c,void * arg)2003 static int slice_decode_thread(AVCodecContext *c, void *arg)
2004 {
2005     MpegEncContext *s   = *(void **) arg;
2006     const uint8_t *buf  = s->gb.buffer;
2007     int mb_y            = s->start_mb_y;
2008     const int field_pic = s->picture_structure != PICT_FRAME;
2009 
2010     s->er.error_count = (3 * (s->end_mb_y - s->start_mb_y) * s->mb_width) >> field_pic;
2011 
2012     for (;;) {
2013         uint32_t start_code;
2014         int ret;
2015 
2016         ret = mpeg_decode_slice(s, mb_y, &buf, s->gb.buffer_end - buf);
2017         emms_c();
2018         av_dlog(c, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
2019                 ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y,
2020                 s->start_mb_y, s->end_mb_y, s->er.error_count);
2021         if (ret < 0) {
2022             if (c->err_recognition & AV_EF_EXPLODE)
2023                 return ret;
2024             if (s->resync_mb_x >= 0 && s->resync_mb_y >= 0)
2025                 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2026                                 s->mb_x, s->mb_y,
2027                                 ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2028         } else {
2029             ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
2030                             s->mb_x - 1, s->mb_y,
2031                             ER_AC_END | ER_DC_END | ER_MV_END);
2032         }
2033 
2034         if (s->mb_y == s->end_mb_y)
2035             return 0;
2036 
2037         start_code = -1;
2038         buf        = avpriv_find_start_code(buf, s->gb.buffer_end, &start_code);
2039         mb_y       = start_code - SLICE_MIN_START_CODE;
2040         if (s->codec_id != AV_CODEC_ID_MPEG1VIDEO && s->mb_height > 2800/16)
2041             mb_y += (*buf&0xE0)<<2;
2042         mb_y <<= field_pic;
2043         if (s->picture_structure == PICT_BOTTOM_FIELD)
2044             mb_y++;
2045         if (mb_y < 0 || mb_y >= s->end_mb_y)
2046             return -1;
2047     }
2048 }
2049 
2050 /**
2051  * Handle slice ends.
2052  * @return 1 if it seems to be the last slice
2053  */
slice_end(AVCodecContext * avctx,AVFrame * pict)2054 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
2055 {
2056     Mpeg1Context *s1  = avctx->priv_data;
2057     MpegEncContext *s = &s1->mpeg_enc_ctx;
2058 
2059     if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
2060         return 0;
2061 
2062     if (s->avctx->hwaccel) {
2063         if (s->avctx->hwaccel->end_frame(s->avctx) < 0)
2064             av_log(avctx, AV_LOG_ERROR,
2065                    "hardware accelerator failed to decode picture\n");
2066     }
2067 
2068     /* end of slice reached */
2069     if (/* s->mb_y << field_pic == s->mb_height && */ !s->first_field && !s1->first_slice) {
2070         /* end of image */
2071 
2072         ff_er_frame_end(&s->er);
2073 
2074         ff_mpv_frame_end(s);
2075 
2076         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay) {
2077             int ret = av_frame_ref(pict, s->current_picture_ptr->f);
2078             if (ret < 0)
2079                 return ret;
2080             ff_print_debug_info(s, s->current_picture_ptr, pict);
2081             ff_mpv_export_qp_table(s, pict, s->current_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2082         } else {
2083             if (avctx->active_thread_type & FF_THREAD_FRAME)
2084                 s->picture_number++;
2085             /* latency of 1 frame for I- and P-frames */
2086             /* XXX: use another variable than picture_number */
2087             if (s->last_picture_ptr) {
2088                 int ret = av_frame_ref(pict, s->last_picture_ptr->f);
2089                 if (ret < 0)
2090                     return ret;
2091                 ff_print_debug_info(s, s->last_picture_ptr, pict);
2092                 ff_mpv_export_qp_table(s, pict, s->last_picture_ptr, FF_QSCALE_TYPE_MPEG2);
2093             }
2094         }
2095 
2096         return 1;
2097     } else {
2098         return 0;
2099     }
2100 }
2101 
mpeg1_decode_sequence(AVCodecContext * avctx,const uint8_t * buf,int buf_size)2102 static int mpeg1_decode_sequence(AVCodecContext *avctx,
2103                                  const uint8_t *buf, int buf_size)
2104 {
2105     Mpeg1Context *s1  = avctx->priv_data;
2106     MpegEncContext *s = &s1->mpeg_enc_ctx;
2107     int width, height;
2108     int i, v, j;
2109 
2110     init_get_bits(&s->gb, buf, buf_size * 8);
2111 
2112     width  = get_bits(&s->gb, 12);
2113     height = get_bits(&s->gb, 12);
2114     if (width == 0 || height == 0) {
2115         av_log(avctx, AV_LOG_WARNING,
2116                "Invalid horizontal or vertical size value.\n");
2117         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2118             return AVERROR_INVALIDDATA;
2119     }
2120     s->aspect_ratio_info = get_bits(&s->gb, 4);
2121     if (s->aspect_ratio_info == 0) {
2122         av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
2123         if (avctx->err_recognition & (AV_EF_BITSTREAM | AV_EF_COMPLIANT))
2124             return -1;
2125     }
2126     s->frame_rate_index = get_bits(&s->gb, 4);
2127     if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
2128         return -1;
2129     s->bit_rate = get_bits(&s->gb, 18) * 400;
2130     if (get_bits1(&s->gb) == 0) /* marker */
2131         return -1;
2132     s->width  = width;
2133     s->height = height;
2134 
2135     s->avctx->rc_buffer_size = get_bits(&s->gb, 10) * 1024 * 16;
2136     skip_bits(&s->gb, 1);
2137 
2138     /* get matrix */
2139     if (get_bits1(&s->gb)) {
2140         load_matrix(s, s->chroma_intra_matrix, s->intra_matrix, 1);
2141     } else {
2142         for (i = 0; i < 64; i++) {
2143             j = s->idsp.idct_permutation[i];
2144             v = ff_mpeg1_default_intra_matrix[i];
2145             s->intra_matrix[j]        = v;
2146             s->chroma_intra_matrix[j] = v;
2147         }
2148     }
2149     if (get_bits1(&s->gb)) {
2150         load_matrix(s, s->chroma_inter_matrix, s->inter_matrix, 0);
2151     } else {
2152         for (i = 0; i < 64; i++) {
2153             int j = s->idsp.idct_permutation[i];
2154             v = ff_mpeg1_default_non_intra_matrix[i];
2155             s->inter_matrix[j]        = v;
2156             s->chroma_inter_matrix[j] = v;
2157         }
2158     }
2159 
2160     if (show_bits(&s->gb, 23) != 0) {
2161         av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2162         return -1;
2163     }
2164 
2165     /* We set MPEG-2 parameters so that it emulates MPEG-1. */
2166     s->progressive_sequence = 1;
2167     s->progressive_frame    = 1;
2168     s->picture_structure    = PICT_FRAME;
2169     s->first_field          = 0;
2170     s->frame_pred_frame_dct = 1;
2171     s->chroma_format        = 1;
2172     s->codec_id             =
2173     s->avctx->codec_id      = AV_CODEC_ID_MPEG1VIDEO;
2174     s->out_format           = FMT_MPEG1;
2175     s->swap_uv              = 0; // AFAIK VCR2 does not have SEQ_HEADER
2176     if (s->flags & CODEC_FLAG_LOW_DELAY)
2177         s->low_delay = 1;
2178 
2179     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
2180         av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2181                s->avctx->rc_buffer_size, s->bit_rate);
2182 
2183     return 0;
2184 }
2185 
vcr2_init_sequence(AVCodecContext * avctx)2186 static int vcr2_init_sequence(AVCodecContext *avctx)
2187 {
2188     Mpeg1Context *s1  = avctx->priv_data;
2189     MpegEncContext *s = &s1->mpeg_enc_ctx;
2190     int i, v;
2191 
2192     /* start new MPEG-1 context decoding */
2193     s->out_format = FMT_MPEG1;
2194     if (s1->mpeg_enc_ctx_allocated) {
2195         ff_mpv_common_end(s);
2196         s1->mpeg_enc_ctx_allocated = 0;
2197     }
2198     s->width            = avctx->coded_width;
2199     s->height           = avctx->coded_height;
2200     avctx->has_b_frames = 0; // true?
2201     s->low_delay        = 1;
2202 
2203     avctx->pix_fmt = mpeg_get_pixelformat(avctx);
2204     setup_hwaccel_for_pixfmt(avctx);
2205 
2206     ff_mpv_idct_init(s);
2207     if (ff_mpv_common_init(s) < 0)
2208         return -1;
2209     s1->mpeg_enc_ctx_allocated = 1;
2210 
2211     for (i = 0; i < 64; i++) {
2212         int j = s->idsp.idct_permutation[i];
2213         v = ff_mpeg1_default_intra_matrix[i];
2214         s->intra_matrix[j]        = v;
2215         s->chroma_intra_matrix[j] = v;
2216 
2217         v = ff_mpeg1_default_non_intra_matrix[i];
2218         s->inter_matrix[j]        = v;
2219         s->chroma_inter_matrix[j] = v;
2220     }
2221 
2222     s->progressive_sequence  = 1;
2223     s->progressive_frame     = 1;
2224     s->picture_structure     = PICT_FRAME;
2225     s->first_field           = 0;
2226     s->frame_pred_frame_dct  = 1;
2227     s->chroma_format         = 1;
2228     if (s->codec_tag == AV_RL32("BW10")) {
2229         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG1VIDEO;
2230     } else {
2231         s->swap_uv = 1; // in case of xvmc we need to swap uv for each MB
2232         s->codec_id              = s->avctx->codec_id = AV_CODEC_ID_MPEG2VIDEO;
2233     }
2234     s1->save_width           = s->width;
2235     s1->save_height          = s->height;
2236     s1->save_progressive_seq = s->progressive_sequence;
2237     return 0;
2238 }
2239 
mpeg_decode_a53_cc(AVCodecContext * avctx,const uint8_t * p,int buf_size)2240 static int mpeg_decode_a53_cc(AVCodecContext *avctx,
2241                               const uint8_t *p, int buf_size)
2242 {
2243     Mpeg1Context *s1 = avctx->priv_data;
2244 
2245     if (buf_size >= 6 &&
2246         p[0] == 'G' && p[1] == 'A' && p[2] == '9' && p[3] == '4' &&
2247         p[4] == 3 && (p[5] & 0x40)) {
2248         /* extract A53 Part 4 CC data */
2249         int cc_count = p[5] & 0x1f;
2250         if (cc_count > 0 && buf_size >= 7 + cc_count * 3) {
2251             av_freep(&s1->a53_caption);
2252             s1->a53_caption_size = cc_count * 3;
2253             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2254             if (s1->a53_caption)
2255                 memcpy(s1->a53_caption, p + 7, s1->a53_caption_size);
2256         }
2257         return 1;
2258     } else if (buf_size >= 11 &&
2259                p[0] == 'C' && p[1] == 'C' && p[2] == 0x01 && p[3] == 0xf8) {
2260         /* extract DVD CC data */
2261         int cc_count = 0;
2262         int i;
2263         // There is a caption count field in the data, but it is often
2264         // incorect.  So count the number of captions present.
2265         for (i = 5; i + 6 <= buf_size && ((p[i] & 0xfe) == 0xfe); i += 6)
2266             cc_count++;
2267         // Transform the DVD format into A53 Part 4 format
2268         if (cc_count > 0) {
2269             av_freep(&s1->a53_caption);
2270             s1->a53_caption_size = cc_count * 6;
2271             s1->a53_caption      = av_malloc(s1->a53_caption_size);
2272             if (s1->a53_caption) {
2273                 uint8_t field1 = !!(p[4] & 0x80);
2274                 uint8_t *cap = s1->a53_caption;
2275                 p += 5;
2276                 for (i = 0; i < cc_count; i++) {
2277                     cap[0] = (p[0] == 0xff && field1) ? 0xfc : 0xfd;
2278                     cap[1] = p[1];
2279                     cap[2] = p[2];
2280                     cap[3] = (p[3] == 0xff && !field1) ? 0xfc : 0xfd;
2281                     cap[4] = p[4];
2282                     cap[5] = p[5];
2283                     cap += 6;
2284                     p += 6;
2285                 }
2286             }
2287         }
2288         return 1;
2289     }
2290     return 0;
2291 }
2292 
mpeg_decode_user_data(AVCodecContext * avctx,const uint8_t * p,int buf_size)2293 static void mpeg_decode_user_data(AVCodecContext *avctx,
2294                                   const uint8_t *p, int buf_size)
2295 {
2296     Mpeg1Context *s = avctx->priv_data;
2297     const uint8_t *buf_end = p + buf_size;
2298     Mpeg1Context *s1 = avctx->priv_data;
2299 
2300     if (buf_size > 29){
2301         int i;
2302         for(i=0; i<20; i++)
2303             if (!memcmp(p+i, "\0TMPGEXS\0", 9)){
2304                 s->tmpgexs= 1;
2305             }
2306 
2307 /*        for(i=0; !(!p[i-2] && !p[i-1] && p[i]==1) && i<buf_size; i++){
2308             av_log(avctx, AV_LOG_ERROR, "%c", p[i]);
2309         }
2310             av_log(avctx, AV_LOG_ERROR, "\n");*/
2311     }
2312 
2313     /* we parse the DTG active format information */
2314     if (buf_end - p >= 5 &&
2315         p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2316         int flags = p[4];
2317         p += 5;
2318         if (flags & 0x80) {
2319             /* skip event id */
2320             p += 2;
2321         }
2322         if (flags & 0x40) {
2323             if (buf_end - p < 1)
2324                 return;
2325 #if FF_API_AFD
2326 FF_DISABLE_DEPRECATION_WARNINGS
2327             avctx->dtg_active_format = p[0] & 0x0f;
2328 FF_ENABLE_DEPRECATION_WARNINGS
2329 #endif /* FF_API_AFD */
2330             s1->has_afd = 1;
2331             s1->afd     = p[0] & 0x0f;
2332         }
2333     } else if (buf_end - p >= 6 &&
2334                p[0] == 'J' && p[1] == 'P' && p[2] == '3' && p[3] == 'D' &&
2335                p[4] == 0x03) { // S3D_video_format_length
2336         // the 0x7F mask ignores the reserved_bit value
2337         const uint8_t S3D_video_format_type = p[5] & 0x7F;
2338 
2339         if (S3D_video_format_type == 0x03 ||
2340             S3D_video_format_type == 0x04 ||
2341             S3D_video_format_type == 0x08 ||
2342             S3D_video_format_type == 0x23) {
2343 
2344             s1->has_stereo3d = 1;
2345 
2346             switch (S3D_video_format_type) {
2347             case 0x03:
2348                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE;
2349                 break;
2350             case 0x04:
2351                 s1->stereo3d.type = AV_STEREO3D_TOPBOTTOM;
2352                 break;
2353             case 0x08:
2354                 s1->stereo3d.type = AV_STEREO3D_2D;
2355                 break;
2356             case 0x23:
2357                 s1->stereo3d.type = AV_STEREO3D_SIDEBYSIDE_QUINCUNX;
2358                 break;
2359             }
2360         }
2361     } else if (mpeg_decode_a53_cc(avctx, p, buf_size)) {
2362         return;
2363     }
2364 }
2365 
mpeg_decode_gop(AVCodecContext * avctx,const uint8_t * buf,int buf_size)2366 static void mpeg_decode_gop(AVCodecContext *avctx,
2367                             const uint8_t *buf, int buf_size)
2368 {
2369     Mpeg1Context *s1  = avctx->priv_data;
2370     MpegEncContext *s = &s1->mpeg_enc_ctx;
2371     int broken_link;
2372     int64_t tc;
2373 
2374     init_get_bits(&s->gb, buf, buf_size * 8);
2375 
2376     tc = avctx->timecode_frame_start = get_bits(&s->gb, 25);
2377 
2378     s->closed_gop = get_bits1(&s->gb);
2379     /* broken_link indicate that after editing the
2380      * reference frames of the first B-Frames after GOP I-Frame
2381      * are missing (open gop) */
2382     broken_link = get_bits1(&s->gb);
2383 
2384     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
2385         char tcbuf[AV_TIMECODE_STR_SIZE];
2386         av_timecode_make_mpeg_tc_string(tcbuf, tc);
2387         av_log(s->avctx, AV_LOG_DEBUG,
2388                "GOP (%s) closed_gop=%d broken_link=%d\n",
2389                tcbuf, s->closed_gop, broken_link);
2390     }
2391 }
2392 
decode_chunks(AVCodecContext * avctx,AVFrame * picture,int * got_output,const uint8_t * buf,int buf_size)2393 static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
2394                          int *got_output, const uint8_t *buf, int buf_size)
2395 {
2396     Mpeg1Context *s = avctx->priv_data;
2397     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2398     const uint8_t *buf_ptr = buf;
2399     const uint8_t *buf_end = buf + buf_size;
2400     int ret, input_size;
2401     int last_code = 0, skip_frame = 0;
2402     int picture_start_code_seen = 0;
2403 
2404     for (;;) {
2405         /* find next start code */
2406         uint32_t start_code = -1;
2407         buf_ptr = avpriv_find_start_code(buf_ptr, buf_end, &start_code);
2408         if (start_code > 0x1ff) {
2409             if (!skip_frame) {
2410                 if (HAVE_THREADS &&
2411                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2412                     !avctx->hwaccel) {
2413                     int i;
2414                     av_assert0(avctx->thread_count > 1);
2415 
2416                     avctx->execute(avctx, slice_decode_thread,
2417                                    &s2->thread_context[0], NULL,
2418                                    s->slice_count, sizeof(void *));
2419                     for (i = 0; i < s->slice_count; i++)
2420                         s2->er.error_count += s2->thread_context[i]->er.error_count;
2421                 }
2422 
2423 #if (CONFIG_MPEG_VDPAU_DECODER == 1) || (CONFIG_MPEG1_VDPAU_DECODER == 1)
2424                 if ((CONFIG_MPEG_VDPAU_DECODER || CONFIG_MPEG1_VDPAU_DECODER)
2425                     && uses_vdpau(avctx))
2426                     ff_vdpau_mpeg_picture_complete(s2, buf, buf_size, s->slice_count);
2427 #endif
2428 
2429                 ret = slice_end(avctx, picture);
2430                 if (ret < 0)
2431                     return ret;
2432                 else if (ret) {
2433                     // FIXME: merge with the stuff in mpeg_decode_slice
2434                     if (s2->last_picture_ptr || s2->low_delay)
2435                         *got_output = 1;
2436                 }
2437             }
2438             s2->pict_type = 0;
2439 
2440             if (avctx->err_recognition & AV_EF_EXPLODE && s2->er.error_count)
2441                 return AVERROR_INVALIDDATA;
2442 
2443             return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2444         }
2445 
2446         input_size = buf_end - buf_ptr;
2447 
2448         if (avctx->debug & FF_DEBUG_STARTCODE)
2449             av_log(avctx, AV_LOG_DEBUG, "%3"PRIX32" at %"PTRDIFF_SPECIFIER" left %d\n",
2450                    start_code, buf_ptr - buf, input_size);
2451 
2452         /* prepare data for next start code */
2453         switch (start_code) {
2454         case SEQ_START_CODE:
2455             if (last_code == 0) {
2456                 mpeg1_decode_sequence(avctx, buf_ptr, input_size);
2457                 if (buf != avctx->extradata)
2458                     s->sync = 1;
2459             } else {
2460                 av_log(avctx, AV_LOG_ERROR,
2461                        "ignoring SEQ_START_CODE after %X\n", last_code);
2462                 if (avctx->err_recognition & AV_EF_EXPLODE)
2463                     return AVERROR_INVALIDDATA;
2464             }
2465             break;
2466 
2467         case PICTURE_START_CODE:
2468             if (picture_start_code_seen && s2->picture_structure == PICT_FRAME) {
2469                /* If it's a frame picture, there can't be more than one picture header.
2470                   Yet, it does happen and we need to handle it. */
2471                av_log(avctx, AV_LOG_WARNING, "ignoring extra picture following a frame-picture\n");
2472                break;
2473             }
2474             picture_start_code_seen = 1;
2475 
2476             if (s2->width <= 0 || s2->height <= 0) {
2477                 av_log(avctx, AV_LOG_ERROR, "Invalid frame dimensions %dx%d.\n",
2478                        s2->width, s2->height);
2479                 return AVERROR_INVALIDDATA;
2480             }
2481 
2482             if (s->tmpgexs){
2483                 s2->intra_dc_precision= 3;
2484                 s2->intra_matrix[0]= 1;
2485             }
2486             if (HAVE_THREADS && (avctx->active_thread_type & FF_THREAD_SLICE) &&
2487                 !avctx->hwaccel && s->slice_count) {
2488                 int i;
2489 
2490                 avctx->execute(avctx, slice_decode_thread,
2491                                s2->thread_context, NULL,
2492                                s->slice_count, sizeof(void *));
2493                 for (i = 0; i < s->slice_count; i++)
2494                     s2->er.error_count += s2->thread_context[i]->er.error_count;
2495                 s->slice_count = 0;
2496             }
2497             if (last_code == 0 || last_code == SLICE_MIN_START_CODE) {
2498                 ret = mpeg_decode_postinit(avctx);
2499                 if (ret < 0) {
2500                     av_log(avctx, AV_LOG_ERROR,
2501                            "mpeg_decode_postinit() failure\n");
2502                     return ret;
2503                 }
2504 
2505                 /* We have a complete image: we try to decompress it. */
2506                 if (mpeg1_decode_picture(avctx, buf_ptr, input_size) < 0)
2507                     s2->pict_type = 0;
2508                 s->first_slice = 1;
2509                 last_code      = PICTURE_START_CODE;
2510             } else {
2511                 av_log(avctx, AV_LOG_ERROR,
2512                        "ignoring pic after %X\n", last_code);
2513                 if (avctx->err_recognition & AV_EF_EXPLODE)
2514                     return AVERROR_INVALIDDATA;
2515             }
2516             break;
2517         case EXT_START_CODE:
2518             init_get_bits(&s2->gb, buf_ptr, input_size * 8);
2519 
2520             switch (get_bits(&s2->gb, 4)) {
2521             case 0x1:
2522                 if (last_code == 0) {
2523                     mpeg_decode_sequence_extension(s);
2524                 } else {
2525                     av_log(avctx, AV_LOG_ERROR,
2526                            "ignoring seq ext after %X\n", last_code);
2527                     if (avctx->err_recognition & AV_EF_EXPLODE)
2528                         return AVERROR_INVALIDDATA;
2529                 }
2530                 break;
2531             case 0x2:
2532                 mpeg_decode_sequence_display_extension(s);
2533                 break;
2534             case 0x3:
2535                 mpeg_decode_quant_matrix_extension(s2);
2536                 break;
2537             case 0x7:
2538                 mpeg_decode_picture_display_extension(s);
2539                 break;
2540             case 0x8:
2541                 if (last_code == PICTURE_START_CODE) {
2542                     mpeg_decode_picture_coding_extension(s);
2543                 } else {
2544                     av_log(avctx, AV_LOG_ERROR,
2545                            "ignoring pic cod ext after %X\n", last_code);
2546                     if (avctx->err_recognition & AV_EF_EXPLODE)
2547                         return AVERROR_INVALIDDATA;
2548                 }
2549                 break;
2550             }
2551             break;
2552         case USER_START_CODE:
2553             mpeg_decode_user_data(avctx, buf_ptr, input_size);
2554             break;
2555         case GOP_START_CODE:
2556             if (last_code == 0) {
2557                 s2->first_field = 0;
2558                 mpeg_decode_gop(avctx, buf_ptr, input_size);
2559                 s->sync = 1;
2560             } else {
2561                 av_log(avctx, AV_LOG_ERROR,
2562                        "ignoring GOP_START_CODE after %X\n", last_code);
2563                 if (avctx->err_recognition & AV_EF_EXPLODE)
2564                     return AVERROR_INVALIDDATA;
2565             }
2566             break;
2567         default:
2568             if (start_code >= SLICE_MIN_START_CODE &&
2569                 start_code <= SLICE_MAX_START_CODE && last_code == PICTURE_START_CODE) {
2570                 if (s2->progressive_sequence && !s2->progressive_frame) {
2571                     s2->progressive_frame = 1;
2572                     av_log(s2->avctx, AV_LOG_ERROR,
2573                            "interlaced frame in progressive sequence, ignoring\n");
2574                 }
2575 
2576                 if (s2->picture_structure == 0 ||
2577                     (s2->progressive_frame && s2->picture_structure != PICT_FRAME)) {
2578                     av_log(s2->avctx, AV_LOG_ERROR,
2579                            "picture_structure %d invalid, ignoring\n",
2580                            s2->picture_structure);
2581                     s2->picture_structure = PICT_FRAME;
2582                 }
2583 
2584                 if (s2->progressive_sequence && !s2->frame_pred_frame_dct)
2585                     av_log(s2->avctx, AV_LOG_WARNING, "invalid frame_pred_frame_dct\n");
2586 
2587                 if (s2->picture_structure == PICT_FRAME) {
2588                     s2->first_field = 0;
2589                     s2->v_edge_pos  = 16 * s2->mb_height;
2590                 } else {
2591                     s2->first_field ^= 1;
2592                     s2->v_edge_pos   = 8 * s2->mb_height;
2593                     memset(s2->mbskip_table, 0, s2->mb_stride * s2->mb_height);
2594                 }
2595             }
2596             if (start_code >= SLICE_MIN_START_CODE &&
2597                 start_code <= SLICE_MAX_START_CODE && last_code != 0) {
2598                 const int field_pic = s2->picture_structure != PICT_FRAME;
2599                 int mb_y = start_code - SLICE_MIN_START_CODE;
2600                 last_code = SLICE_MIN_START_CODE;
2601                 if (s2->codec_id != AV_CODEC_ID_MPEG1VIDEO && s2->mb_height > 2800/16)
2602                     mb_y += (*buf_ptr&0xE0)<<2;
2603 
2604                 mb_y <<= field_pic;
2605                 if (s2->picture_structure == PICT_BOTTOM_FIELD)
2606                     mb_y++;
2607 
2608                 if (buf_end - buf_ptr < 2) {
2609                     av_log(s2->avctx, AV_LOG_ERROR, "slice too small\n");
2610                     return AVERROR_INVALIDDATA;
2611                 }
2612 
2613                 if (mb_y >= s2->mb_height) {
2614                     av_log(s2->avctx, AV_LOG_ERROR,
2615                            "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
2616                     return -1;
2617                 }
2618 
2619                 if (!s2->last_picture_ptr) {
2620                     /* Skip B-frames if we do not have reference frames and
2621                      * GOP is not closed. */
2622                     if (s2->pict_type == AV_PICTURE_TYPE_B) {
2623                         if (!s2->closed_gop) {
2624                             skip_frame = 1;
2625                             break;
2626                         }
2627                     }
2628                 }
2629                 if (s2->pict_type == AV_PICTURE_TYPE_I || (s2->flags2 & CODEC_FLAG2_SHOW_ALL))
2630                     s->sync = 1;
2631                 if (!s2->next_picture_ptr) {
2632                     /* Skip P-frames if we do not have a reference frame or
2633                      * we have an invalid header. */
2634                     if (s2->pict_type == AV_PICTURE_TYPE_P && !s->sync) {
2635                         skip_frame = 1;
2636                         break;
2637                     }
2638                 }
2639                 if ((avctx->skip_frame >= AVDISCARD_NONREF &&
2640                      s2->pict_type == AV_PICTURE_TYPE_B) ||
2641                     (avctx->skip_frame >= AVDISCARD_NONKEY &&
2642                      s2->pict_type != AV_PICTURE_TYPE_I) ||
2643                     avctx->skip_frame >= AVDISCARD_ALL) {
2644                     skip_frame = 1;
2645                     break;
2646                 }
2647 
2648                 if (!s->mpeg_enc_ctx_allocated)
2649                     break;
2650 
2651                 if (s2->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
2652                     if (mb_y < avctx->skip_top ||
2653                         mb_y >= s2->mb_height - avctx->skip_bottom)
2654                         break;
2655                 }
2656 
2657                 if (!s2->pict_type) {
2658                     av_log(avctx, AV_LOG_ERROR, "Missing picture start code\n");
2659                     if (avctx->err_recognition & AV_EF_EXPLODE)
2660                         return AVERROR_INVALIDDATA;
2661                     break;
2662                 }
2663 
2664                 if (s->first_slice) {
2665                     skip_frame     = 0;
2666                     s->first_slice = 0;
2667                     if (mpeg_field_start(s2, buf, buf_size) < 0)
2668                         return -1;
2669                 }
2670                 if (!s2->current_picture_ptr) {
2671                     av_log(avctx, AV_LOG_ERROR,
2672                            "current_picture not initialized\n");
2673                     return AVERROR_INVALIDDATA;
2674                 }
2675 
2676                 if (uses_vdpau(avctx)) {
2677                     s->slice_count++;
2678                     break;
2679                 }
2680 
2681                 if (HAVE_THREADS &&
2682                     (avctx->active_thread_type & FF_THREAD_SLICE) &&
2683                     !avctx->hwaccel) {
2684                     int threshold = (s2->mb_height * s->slice_count +
2685                                      s2->slice_context_count / 2) /
2686                                     s2->slice_context_count;
2687                     av_assert0(avctx->thread_count > 1);
2688                     if (threshold <= mb_y) {
2689                         MpegEncContext *thread_context = s2->thread_context[s->slice_count];
2690 
2691                         thread_context->start_mb_y = mb_y;
2692                         thread_context->end_mb_y   = s2->mb_height;
2693                         if (s->slice_count) {
2694                             s2->thread_context[s->slice_count - 1]->end_mb_y = mb_y;
2695                             ret = ff_update_duplicate_context(thread_context, s2);
2696                             if (ret < 0)
2697                                 return ret;
2698                         }
2699                         init_get_bits(&thread_context->gb, buf_ptr, input_size * 8);
2700                         s->slice_count++;
2701                     }
2702                     buf_ptr += 2; // FIXME add minimum number of bytes per slice
2703                 } else {
2704                     ret = mpeg_decode_slice(s2, mb_y, &buf_ptr, input_size);
2705                     emms_c();
2706 
2707                     if (ret < 0) {
2708                         if (avctx->err_recognition & AV_EF_EXPLODE)
2709                             return ret;
2710                         if (s2->resync_mb_x >= 0 && s2->resync_mb_y >= 0)
2711                             ff_er_add_slice(&s2->er, s2->resync_mb_x,
2712                                             s2->resync_mb_y, s2->mb_x, s2->mb_y,
2713                                             ER_AC_ERROR | ER_DC_ERROR | ER_MV_ERROR);
2714                     } else {
2715                         ff_er_add_slice(&s2->er, s2->resync_mb_x,
2716                                         s2->resync_mb_y, s2->mb_x - 1, s2->mb_y,
2717                                         ER_AC_END | ER_DC_END | ER_MV_END);
2718                     }
2719                 }
2720             }
2721             break;
2722         }
2723     }
2724 }
2725 
mpeg_decode_frame(AVCodecContext * avctx,void * data,int * got_output,AVPacket * avpkt)2726 static int mpeg_decode_frame(AVCodecContext *avctx, void *data,
2727                              int *got_output, AVPacket *avpkt)
2728 {
2729     const uint8_t *buf = avpkt->data;
2730     int ret;
2731     int buf_size = avpkt->size;
2732     Mpeg1Context *s = avctx->priv_data;
2733     AVFrame *picture = data;
2734     MpegEncContext *s2 = &s->mpeg_enc_ctx;
2735 
2736     if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2737         /* special case for last picture */
2738         if (s2->low_delay == 0 && s2->next_picture_ptr) {
2739             int ret = av_frame_ref(picture, s2->next_picture_ptr->f);
2740             if (ret < 0)
2741                 return ret;
2742 
2743             s2->next_picture_ptr = NULL;
2744 
2745             *got_output = 1;
2746         }
2747         return buf_size;
2748     }
2749 
2750     if (s2->flags & CODEC_FLAG_TRUNCATED) {
2751         int next = ff_mpeg1_find_frame_end(&s2->parse_context, buf,
2752                                            buf_size, NULL);
2753 
2754         if (ff_combine_frame(&s2->parse_context, next,
2755                              (const uint8_t **) &buf, &buf_size) < 0)
2756             return buf_size;
2757     }
2758 
2759     s2->codec_tag = avpriv_toupper4(avctx->codec_tag);
2760     if (s->mpeg_enc_ctx_allocated == 0 && (   s2->codec_tag == AV_RL32("VCR2")
2761                                            || s2->codec_tag == AV_RL32("BW10")
2762                                           ))
2763         vcr2_init_sequence(avctx);
2764 
2765     s->slice_count = 0;
2766 
2767     if (avctx->extradata && !s->extradata_decoded) {
2768         ret = decode_chunks(avctx, picture, got_output,
2769                             avctx->extradata, avctx->extradata_size);
2770         if (*got_output) {
2771             av_log(avctx, AV_LOG_ERROR, "picture in extradata\n");
2772             *got_output = 0;
2773         }
2774         s->extradata_decoded = 1;
2775         if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
2776             s2->current_picture_ptr = NULL;
2777             return ret;
2778         }
2779     }
2780 
2781     ret = decode_chunks(avctx, picture, got_output, buf, buf_size);
2782     if (ret<0 || *got_output)
2783         s2->current_picture_ptr = NULL;
2784 
2785     return ret;
2786 }
2787 
flush(AVCodecContext * avctx)2788 static void flush(AVCodecContext *avctx)
2789 {
2790     Mpeg1Context *s = avctx->priv_data;
2791 
2792     s->sync       = 0;
2793 
2794     ff_mpeg_flush(avctx);
2795 }
2796 
mpeg_decode_end(AVCodecContext * avctx)2797 static av_cold int mpeg_decode_end(AVCodecContext *avctx)
2798 {
2799     Mpeg1Context *s = avctx->priv_data;
2800 
2801     if (s->mpeg_enc_ctx_allocated)
2802         ff_mpv_common_end(&s->mpeg_enc_ctx);
2803     av_freep(&s->a53_caption);
2804     return 0;
2805 }
2806 
2807 static const AVProfile mpeg2_video_profiles[] = {
2808     { FF_PROFILE_MPEG2_422,          "4:2:2"              },
2809     { FF_PROFILE_MPEG2_HIGH,         "High"               },
2810     { FF_PROFILE_MPEG2_SS,           "Spatially Scalable" },
2811     { FF_PROFILE_MPEG2_SNR_SCALABLE, "SNR Scalable"       },
2812     { FF_PROFILE_MPEG2_MAIN,         "Main"               },
2813     { FF_PROFILE_MPEG2_SIMPLE,       "Simple"             },
2814     { FF_PROFILE_RESERVED,           "Reserved"           },
2815     { FF_PROFILE_RESERVED,           "Reserved"           },
2816     { FF_PROFILE_UNKNOWN                                  },
2817 };
2818 
2819 AVCodec ff_mpeg1video_decoder = {
2820 	.name                  = "mpeg1video",
2821     .long_name             = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2822     .type                  = AVMEDIA_TYPE_VIDEO,
2823     .id                    = AV_CODEC_ID_MPEG1VIDEO,
2824     .priv_data_size        = sizeof(Mpeg1Context),
2825     .init                  = mpeg_decode_init,
2826     .close                 = mpeg_decode_end,
2827     .decode                = mpeg_decode_frame,
2828     .capabilities          = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2829                              CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2830                              CODEC_CAP_SLICE_THREADS,
2831     .flush                 = flush,
2832     .max_lowres            = 3,
2833     .update_thread_context = ONLY_IF_THREADS_ENABLED(mpeg_decode_update_thread_context)
2834 };
2835 
2836 AVCodec ff_mpeg2video_decoder = {
2837 	.name           = "mpeg2video",
2838     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-2 video"),
2839     .type           = AVMEDIA_TYPE_VIDEO,
2840     .id             = AV_CODEC_ID_MPEG2VIDEO,
2841     .priv_data_size = sizeof(Mpeg1Context),
2842     .init           = mpeg_decode_init,
2843     .close          = mpeg_decode_end,
2844     .decode         = mpeg_decode_frame,
2845     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2846                       CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY |
2847                       CODEC_CAP_SLICE_THREADS,
2848     .flush          = flush,
2849     .max_lowres     = 3,
2850     .profiles       = NULL_IF_CONFIG_SMALL(mpeg2_video_profiles),
2851 };
2852 
2853 //legacy decoder
2854 AVCodec ff_mpegvideo_decoder = {
2855 	.name           = "mpegvideo",
2856     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video"),
2857     .type           = AVMEDIA_TYPE_VIDEO,
2858     .id             = AV_CODEC_ID_MPEG2VIDEO,
2859     .priv_data_size = sizeof(Mpeg1Context),
2860     .init           = mpeg_decode_init,
2861     .close          = mpeg_decode_end,
2862     .decode         = mpeg_decode_frame,
2863     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
2864     .flush          = flush,
2865     .max_lowres     = 3,
2866 };
2867 
2868 #if FF_API_XVMC
2869 #if CONFIG_MPEG_XVMC_DECODER
mpeg_mc_decode_init(AVCodecContext * avctx)2870 static av_cold int mpeg_mc_decode_init(AVCodecContext *avctx)
2871 {
2872     if (avctx->active_thread_type & FF_THREAD_SLICE)
2873         return -1;
2874     if (!(avctx->slice_flags & SLICE_FLAG_CODED_ORDER))
2875         return -1;
2876     if (!(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) {
2877         av_dlog(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2878     }
2879     mpeg_decode_init(avctx);
2880 
2881     avctx->pix_fmt           = AV_PIX_FMT_XVMC_MPEG2_IDCT;
2882     avctx->xvmc_acceleration = 2; // 2 - the blocks are packed!
2883 
2884     return 0;
2885 }
2886 
2887 AVCodec ff_mpeg_xvmc_decoder = {
2888     .name           = "mpegvideo_xvmc",
2889     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video XvMC (X-Video Motion Compensation)"),
2890     .type           = AVMEDIA_TYPE_VIDEO,
2891     .id             = AV_CODEC_ID_MPEG2VIDEO_XVMC,
2892     .priv_data_size = sizeof(Mpeg1Context),
2893     .init           = mpeg_mc_decode_init,
2894     .close          = mpeg_decode_end,
2895     .decode         = mpeg_decode_frame,
2896     .capabilities   = CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 |
2897                       CODEC_CAP_TRUNCATED | CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2898     .flush          = flush,
2899 };
2900 
2901 #endif
2902 #endif /* FF_API_XVMC */
2903 
2904 #if CONFIG_MPEG_VDPAU_DECODER
2905 AVCodec ff_mpeg_vdpau_decoder = {
2906     .name           = "mpegvideo_vdpau",
2907     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1/2 video (VDPAU acceleration)"),
2908     .type           = AVMEDIA_TYPE_VIDEO,
2909     .id             = AV_CODEC_ID_MPEG2VIDEO,
2910     .priv_data_size = sizeof(Mpeg1Context),
2911     .init           = mpeg_decode_init,
2912     .close          = mpeg_decode_end,
2913     .decode         = mpeg_decode_frame,
2914     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2915                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2916     .flush          = flush,
2917 };
2918 #endif
2919 
2920 #if CONFIG_MPEG1_VDPAU_DECODER
2921 AVCodec ff_mpeg1_vdpau_decoder = {
2922     .name           = "mpeg1video_vdpau",
2923     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-1 video (VDPAU acceleration)"),
2924     .type           = AVMEDIA_TYPE_VIDEO,
2925     .id             = AV_CODEC_ID_MPEG1VIDEO,
2926     .priv_data_size = sizeof(Mpeg1Context),
2927     .init           = mpeg_decode_init,
2928     .close          = mpeg_decode_end,
2929     .decode         = mpeg_decode_frame,
2930     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED |
2931                       CODEC_CAP_HWACCEL_VDPAU | CODEC_CAP_DELAY,
2932     .flush          = flush,
2933 };
2934 #endif
2935