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source: vbox/trunk/src/libs/ffmpeg-20060710/libavformat/avidec.c@ 11537

Last change on this file since 11537 was 5776, checked in by vboxsync, 17 years ago

ffmpeg: exported to OSE
File size: 29.6 KB
Line 
1/*
2 * AVI decoder.
3 * Copyright (c) 2001 Fabrice Bellard.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19#include "avformat.h"
20#include "avi.h"
21#include "dv.h"
22
23#undef NDEBUG
24#include <assert.h>
25
26//#define DEBUG
27//#define DEBUG_SEEK
28
29typedef struct AVIStream {
30 int64_t frame_offset; /* current frame (video) or byte (audio) counter
31 (used to compute the pts) */
32 int remaining;
33 int packet_size;
34
35 int scale;
36 int rate;
37 int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
38
39 int64_t cum_len; /* temporary storage (used during seek) */
40
41 int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
42 int prefix_count;
43} AVIStream;
44
45typedef struct {
46 int64_t riff_end;
47 int64_t movi_end;
48 offset_t movi_list;
49 int index_loaded;
50 int is_odml;
51 int non_interleaved;
52 int stream_index;
53 DVDemuxContext* dv_demux;
54} AVIContext;
55
56static int avi_load_index(AVFormatContext *s);
57static int guess_ni_flag(AVFormatContext *s);
58
59#ifdef DEBUG
60static void print_tag(const char *str, unsigned int tag, int size)
61{
62 printf("%s: tag=%c%c%c%c size=0x%x\n",
63 str, tag & 0xff,
64 (tag >> 8) & 0xff,
65 (tag >> 16) & 0xff,
66 (tag >> 24) & 0xff,
67 size);
68}
69#endif
70
71static int get_riff(AVIContext *avi, ByteIOContext *pb)
72{
73 uint32_t tag;
74 /* check RIFF header */
75 tag = get_le32(pb);
76
77 if (tag != MKTAG('R', 'I', 'F', 'F'))
78 return -1;
79 avi->riff_end = get_le32(pb); /* RIFF chunk size */
80 avi->riff_end += url_ftell(pb); /* RIFF chunk end */
81 tag = get_le32(pb);
82 if (tag != MKTAG('A', 'V', 'I', ' ') && tag != MKTAG('A', 'V', 'I', 'X'))
83 return -1;
84
85 return 0;
86}
87
88static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
89 AVIContext *avi = s->priv_data;
90 ByteIOContext *pb = &s->pb;
91 int longs_pre_entry= get_le16(pb);
92 int index_sub_type = get_byte(pb);
93 int index_type = get_byte(pb);
94 int entries_in_use = get_le32(pb);
95 int chunk_id = get_le32(pb);
96 int64_t base = get_le64(pb);
97 int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
98 AVStream *st;
99 AVIStream *ast;
100 int i;
101 int64_t last_pos= -1;
102
103// av_log(s, AV_LOG_ERROR, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%Ld\n",
104// longs_pre_entry,index_type, entries_in_use, chunk_id, base);
105
106 if(stream_id > s->nb_streams || stream_id < 0)
107 return -1;
108 st= s->streams[stream_id];
109 ast = st->priv_data;
110
111 if(index_sub_type)
112 return -1;
113
114 get_le32(pb);
115
116 if(index_type && longs_pre_entry != 2)
117 return -1;
118 if(index_type>1)
119 return -1;
120
121 for(i=0; i<entries_in_use; i++){
122 if(index_type){
123 int64_t pos= get_le32(pb) + base - 8;
124 int len = get_le32(pb);
125 int key= len >= 0;
126 len &= 0x7FFFFFFF;
127
128//av_log(s, AV_LOG_ERROR, "pos:%Ld, len:%X\n", pos, len);
129 if(last_pos == pos || pos == base - 8)
130 avi->non_interleaved= 1;
131 else
132 av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
133
134 if(ast->sample_size)
135 ast->cum_len += len / ast->sample_size;
136 else
137 ast->cum_len ++;
138 last_pos= pos;
139 }else{
140 int64_t offset, pos;
141 int duration;
142 offset = get_le64(pb);
143 get_le32(pb); /* size */
144 duration = get_le32(pb);
145 pos = url_ftell(pb);
146
147 url_fseek(pb, offset+8, SEEK_SET);
148 read_braindead_odml_indx(s, frame_num);
149 frame_num += duration;
150
151 url_fseek(pb, pos, SEEK_SET);
152 }
153 }
154 return 0;
155}
156
157static void clean_index(AVFormatContext *s){
158 int i, j;
159
160 for(i=0; i<s->nb_streams; i++){
161 AVStream *st = s->streams[i];
162 AVIStream *ast = st->priv_data;
163 int n= st->nb_index_entries;
164 int max= ast->sample_size;
165 int64_t pos, size, ts;
166
167 if(n != 1 || ast->sample_size==0)
168 continue;
169
170 while(max < 1024) max+=max;
171
172 pos= st->index_entries[0].pos;
173 size= st->index_entries[0].size;
174 ts= st->index_entries[0].timestamp;
175
176 for(j=0; j<size; j+=max){
177 av_add_index_entry(st, pos+j, ts + j/ast->sample_size, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
178 }
179 }
180}
181
182static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
183{
184 AVIContext *avi = s->priv_data;
185 ByteIOContext *pb = &s->pb;
186 uint32_t tag, tag1, handler;
187 int codec_type, stream_index, frame_period, bit_rate;
188 unsigned int size, nb_frames;
189 int i, n;
190 AVStream *st;
191 AVIStream *ast = NULL;
192 int xan_video = 0; /* hack to support Xan A/V */
193
194 avi->stream_index= -1;
195
196 if (get_riff(avi, pb) < 0)
197 return -1;
198
199 /* first list tag */
200 stream_index = -1;
201 codec_type = -1;
202 frame_period = 0;
203 for(;;) {
204 if (url_feof(pb))
205 goto fail;
206 tag = get_le32(pb);
207 size = get_le32(pb);
208#ifdef DEBUG
209 print_tag("tag", tag, size);
210#endif
211
212 switch(tag) {
213 case MKTAG('L', 'I', 'S', 'T'):
214 /* ignored, except when start of video packets */
215 tag1 = get_le32(pb);
216#ifdef DEBUG
217 print_tag("list", tag1, 0);
218#endif
219 if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
220 avi->movi_list = url_ftell(pb) - 4;
221 if(size) avi->movi_end = avi->movi_list + size;
222 else avi->movi_end = url_fsize(pb);
223#ifdef DEBUG
224 printf("movi end=%Lx\n", avi->movi_end);
225#endif
226 goto end_of_header;
227 }
228 break;
229 case MKTAG('d', 'm', 'l', 'h'):
230 avi->is_odml = 1;
231 url_fskip(pb, size + (size & 1));
232 break;
233 case MKTAG('a', 'v', 'i', 'h'):
234 /* avi header */
235 /* using frame_period is bad idea */
236 frame_period = get_le32(pb);
237 bit_rate = get_le32(pb) * 8;
238 get_le32(pb);
239 avi->non_interleaved |= get_le32(pb) & AVIF_MUSTUSEINDEX;
240
241 url_fskip(pb, 2 * 4);
242 n = get_le32(pb);
243 for(i=0;i<n;i++) {
244 AVIStream *ast;
245 st = av_new_stream(s, i);
246 if (!st)
247 goto fail;
248
249 ast = av_mallocz(sizeof(AVIStream));
250 if (!ast)
251 goto fail;
252 st->priv_data = ast;
253 }
254 url_fskip(pb, size - 7 * 4);
255 break;
256 case MKTAG('s', 't', 'r', 'h'):
257 /* stream header */
258 stream_index++;
259 tag1 = get_le32(pb);
260 handler = get_le32(pb); /* codec tag */
261#ifdef DEBUG
262 print_tag("strh", tag1, -1);
263#endif
264 if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
265 /*
266 * After some consideration -- I don't think we
267 * have to support anything but DV in a type1 AVIs.
268 */
269 if (s->nb_streams != 1)
270 goto fail;
271
272 if (handler != MKTAG('d', 'v', 's', 'd') &&
273 handler != MKTAG('d', 'v', 'h', 'd') &&
274 handler != MKTAG('d', 'v', 's', 'l'))
275 goto fail;
276
277 ast = s->streams[0]->priv_data;
278 av_freep(&s->streams[0]->codec->extradata);
279 av_freep(&s->streams[0]);
280 s->nb_streams = 0;
281 avi->dv_demux = dv_init_demux(s);
282 if (!avi->dv_demux)
283 goto fail;
284 s->streams[0]->priv_data = ast;
285 url_fskip(pb, 3 * 4);
286 ast->scale = get_le32(pb);
287 ast->rate = get_le32(pb);
288 stream_index = s->nb_streams - 1;
289 url_fskip(pb, size - 7*4);
290 break;
291 }
292
293 if (stream_index >= s->nb_streams) {
294 url_fskip(pb, size - 8);
295 /* ignore padding stream */
296 if (tag1 == MKTAG('p', 'a', 'd', 's'))
297 stream_index--;
298 break;
299 }
300 st = s->streams[stream_index];
301 ast = st->priv_data;
302 st->codec->stream_codec_tag= handler;
303
304 get_le32(pb); /* flags */
305 get_le16(pb); /* priority */
306 get_le16(pb); /* language */
307 get_le32(pb); /* initial frame */
308 ast->scale = get_le32(pb);
309 ast->rate = get_le32(pb);
310 if(ast->scale && ast->rate){
311 }else if(frame_period){
312 ast->rate = 1000000;
313 ast->scale = frame_period;
314 }else{
315 ast->rate = 25;
316 ast->scale = 1;
317 }
318 av_set_pts_info(st, 64, ast->scale, ast->rate);
319
320 ast->cum_len=get_le32(pb); /* start */
321 nb_frames = get_le32(pb);
322
323 st->start_time = 0;
324 st->duration = nb_frames;
325 get_le32(pb); /* buffer size */
326 get_le32(pb); /* quality */
327 ast->sample_size = get_le32(pb); /* sample ssize */
328// av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);
329
330 switch(tag1) {
331 case MKTAG('v', 'i', 'd', 's'):
332 codec_type = CODEC_TYPE_VIDEO;
333
334 ast->sample_size = 0;
335 break;
336 case MKTAG('a', 'u', 'd', 's'):
337 codec_type = CODEC_TYPE_AUDIO;
338 break;
339 case MKTAG('t', 'x', 't', 's'):
340 //FIXME
341 codec_type = CODEC_TYPE_DATA; //CODEC_TYPE_SUB ? FIXME
342 break;
343 case MKTAG('p', 'a', 'd', 's'):
344 codec_type = CODEC_TYPE_UNKNOWN;
345 stream_index--;
346 break;
347 default:
348 av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
349 goto fail;
350 }
351 ast->frame_offset= ast->cum_len * FFMAX(ast->sample_size, 1);
352 url_fskip(pb, size - 12 * 4);
353 break;
354 case MKTAG('s', 't', 'r', 'f'):
355 /* stream header */
356 if (stream_index >= s->nb_streams || avi->dv_demux) {
357 url_fskip(pb, size);
358 } else {
359 st = s->streams[stream_index];
360 switch(codec_type) {
361 case CODEC_TYPE_VIDEO:
362 get_le32(pb); /* size */
363 st->codec->width = get_le32(pb);
364 st->codec->height = get_le32(pb);
365 get_le16(pb); /* panes */
366 st->codec->bits_per_sample= get_le16(pb); /* depth */
367 tag1 = get_le32(pb);
368 get_le32(pb); /* ImageSize */
369 get_le32(pb); /* XPelsPerMeter */
370 get_le32(pb); /* YPelsPerMeter */
371 get_le32(pb); /* ClrUsed */
372 get_le32(pb); /* ClrImportant */
373
374 if(size > 10*4 && size<(1<<30)){
375 st->codec->extradata_size= size - 10*4;
376 st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
377 get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
378 }
379
380 if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
381 get_byte(pb);
382
383 /* Extract palette from extradata if bpp <= 8 */
384 /* This code assumes that extradata contains only palette */
385 /* This is true for all paletted codecs implemented in ffmpeg */
386 if (st->codec->extradata_size && (st->codec->bits_per_sample <= 8)) {
387 st->codec->palctrl = av_mallocz(sizeof(AVPaletteControl));
388#ifdef WORDS_BIGENDIAN
389 for (i = 0; i < FFMIN(st->codec->extradata_size, AVPALETTE_SIZE)/4; i++)
390 st->codec->palctrl->palette[i] = bswap_32(((uint32_t*)st->codec->extradata)[i]);
391#else
392 memcpy(st->codec->palctrl->palette, st->codec->extradata,
393 FFMIN(st->codec->extradata_size, AVPALETTE_SIZE));
394#endif
395 st->codec->palctrl->palette_changed = 1;
396 }
397
398#ifdef DEBUG
399 print_tag("video", tag1, 0);
400#endif
401 st->codec->codec_type = CODEC_TYPE_VIDEO;
402 st->codec->codec_tag = tag1;
403 st->codec->codec_id = codec_get_id(codec_bmp_tags, tag1);
404 if (st->codec->codec_id == CODEC_ID_XAN_WC4)
405 xan_video = 1;
406 st->need_parsing = 2; //only parse headers dont do slower repacketization, this is needed to get the pict type which is needed for generating correct pts
407// url_fskip(pb, size - 5 * 4);
408 break;
409 case CODEC_TYPE_AUDIO:
410 get_wav_header(pb, st->codec, size);
411 if(ast->sample_size && st->codec->block_align && ast->sample_size % st->codec->block_align)
412 av_log(s, AV_LOG_DEBUG, "invalid sample size or block align detected\n");
413 if (size%2) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
414 url_fskip(pb, 1);
415 /* special case time: To support Xan DPCM, hardcode
416 * the format if Xxan is the video codec */
417 st->need_parsing = 1;
418 /* force parsing as several audio frames can be in
419 one packet */
420 if (xan_video)
421 st->codec->codec_id = CODEC_ID_XAN_DPCM;
422 break;
423 default:
424 st->codec->codec_type = CODEC_TYPE_DATA;
425 st->codec->codec_id= CODEC_ID_NONE;
426 st->codec->codec_tag= 0;
427 url_fskip(pb, size);
428 break;
429 }
430 }
431 break;
432 case MKTAG('i', 'n', 'd', 'x'):
433 i= url_ftell(pb);
434 if(!url_is_streamed(pb)){
435 read_braindead_odml_indx(s, 0);
436 avi->index_loaded=1;
437 }
438 url_fseek(pb, i+size, SEEK_SET);
439 break;
440 default:
441 /* skip tag */
442 size += (size & 1);
443 url_fskip(pb, size);
444 break;
445 }
446 }
447 end_of_header:
448 /* check stream number */
449 if (stream_index != s->nb_streams - 1) {
450 fail:
451 for(i=0;i<s->nb_streams;i++) {
452 av_freep(&s->streams[i]->codec->extradata);
453 av_freep(&s->streams[i]);
454 }
455 return -1;
456 }
457
458 if(!avi->index_loaded && !url_is_streamed(pb))
459 avi_load_index(s);
460 avi->index_loaded = 1;
461 avi->non_interleaved |= guess_ni_flag(s);
462 if(avi->non_interleaved)
463 clean_index(s);
464
465 return 0;
466}
467
468static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
469{
470 AVIContext *avi = s->priv_data;
471 ByteIOContext *pb = &s->pb;
472 int n, d[8], size;
473 offset_t i, sync;
474 void* dstr;
475
476 if (avi->dv_demux) {
477 size = dv_get_packet(avi->dv_demux, pkt);
478 if (size >= 0)
479 return size;
480 }
481
482 if(avi->non_interleaved){
483 int best_stream_index = 0;
484 AVStream *best_st= NULL;
485 AVIStream *best_ast;
486 int64_t best_ts= INT64_MAX;
487 int i;
488
489 for(i=0; i<s->nb_streams; i++){
490 AVStream *st = s->streams[i];
491 AVIStream *ast = st->priv_data;
492 int64_t ts= ast->frame_offset;
493
494 if(ast->sample_size)
495 ts /= ast->sample_size;
496 ts= av_rescale(ts, AV_TIME_BASE * (int64_t)st->time_base.num, st->time_base.den);
497
498// av_log(NULL, AV_LOG_DEBUG, "%Ld %d/%d %Ld\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);
499 if(ts < best_ts){
500 best_ts= ts;
501 best_st= st;
502 best_stream_index= i;
503 }
504 }
505 best_ast = best_st->priv_data;
506 best_ts= av_rescale(best_ts, best_st->time_base.den, AV_TIME_BASE * (int64_t)best_st->time_base.num); //FIXME a little ugly
507 if(best_ast->remaining)
508 i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
509 else
510 i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
511
512// av_log(NULL, AV_LOG_DEBUG, "%d\n", i);
513 if(i>=0){
514 int64_t pos= best_st->index_entries[i].pos;
515 pos += best_ast->packet_size - best_ast->remaining;
516 url_fseek(&s->pb, pos + 8, SEEK_SET);
517// av_log(NULL, AV_LOG_DEBUG, "pos=%Ld\n", pos);
518
519 assert(best_ast->remaining <= best_ast->packet_size);
520
521 avi->stream_index= best_stream_index;
522 if(!best_ast->remaining)
523 best_ast->packet_size=
524 best_ast->remaining= best_st->index_entries[i].size;
525 }
526 }
527
528resync:
529 if(avi->stream_index >= 0){
530 AVStream *st= s->streams[ avi->stream_index ];
531 AVIStream *ast= st->priv_data;
532 int size;
533
534 if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
535 size= INT_MAX;
536 else if(ast->sample_size < 32)
537 size= 64*ast->sample_size;
538 else
539 size= ast->sample_size;
540
541 if(size > ast->remaining)
542 size= ast->remaining;
543 av_get_packet(pb, pkt, size);
544
545 if (avi->dv_demux) {
546 dstr = pkt->destruct;
547 size = dv_produce_packet(avi->dv_demux, pkt,
548 pkt->data, pkt->size);
549 pkt->destruct = dstr;
550 pkt->flags |= PKT_FLAG_KEY;
551 } else {
552 /* XXX: how to handle B frames in avi ? */
553 pkt->dts = ast->frame_offset;
554// pkt->dts += ast->start;
555 if(ast->sample_size)
556 pkt->dts /= ast->sample_size;
557//av_log(NULL, AV_LOG_DEBUG, "dts:%Ld offset:%Ld %d/%d smpl_siz:%d base:%d st:%d size:%d\n", pkt->dts, ast->frame_offset, ast->scale, ast->rate, ast->sample_size, AV_TIME_BASE, avi->stream_index, size);
558 pkt->stream_index = avi->stream_index;
559
560 if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
561 if(st->index_entries){
562 AVIndexEntry *e;
563 int index;
564
565 index= av_index_search_timestamp(st, pkt->dts, 0);
566 e= &st->index_entries[index];
567
568 if(index >= 0 && e->timestamp == ast->frame_offset){
569 if (e->flags & AVINDEX_KEYFRAME)
570 pkt->flags |= PKT_FLAG_KEY;
571 }
572 } else {
573 /* if no index, better to say that all frames
574 are key frames */
575 pkt->flags |= PKT_FLAG_KEY;
576 }
577 } else {
578 pkt->flags |= PKT_FLAG_KEY;
579 }
580 if(ast->sample_size)
581 ast->frame_offset += pkt->size;
582 else
583 ast->frame_offset++;
584 }
585 ast->remaining -= size;
586 if(!ast->remaining){
587 avi->stream_index= -1;
588 ast->packet_size= 0;
589 if (size & 1) {
590 get_byte(pb);
591 size++;
592 }
593 }
594
595 return size;
596 }
597
598 memset(d, -1, sizeof(int)*8);
599 for(i=sync=url_ftell(pb); !url_feof(pb); i++) {
600 int j;
601
602 if (i >= avi->movi_end) {
603 if (avi->is_odml) {
604 url_fskip(pb, avi->riff_end - i);
605 avi->riff_end = avi->movi_end = url_fsize(pb);
606 } else
607 break;
608 }
609
610 for(j=0; j<7; j++)
611 d[j]= d[j+1];
612 d[7]= get_byte(pb);
613
614 size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
615
616 if( d[2] >= '0' && d[2] <= '9'
617 && d[3] >= '0' && d[3] <= '9'){
618 n= (d[2] - '0') * 10 + (d[3] - '0');
619 }else{
620 n= 100; //invalid stream id
621 }
622//av_log(NULL, AV_LOG_DEBUG, "%X %X %X %X %X %X %X %X %lld %d %d\n", d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
623 if(i + size > avi->movi_end || d[0]<0)
624 continue;
625
626 //parse ix##
627 if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
628 //parse JUNK
629 ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')){
630 url_fskip(pb, size);
631//av_log(NULL, AV_LOG_DEBUG, "SKIP\n");
632 goto resync;
633 }
634
635 if( d[0] >= '0' && d[0] <= '9'
636 && d[1] >= '0' && d[1] <= '9'){
637 n= (d[0] - '0') * 10 + (d[1] - '0');
638 }else{
639 n= 100; //invalid stream id
640 }
641
642 //parse ##dc/##wb
643 if(n < s->nb_streams){
644 AVStream *st;
645 AVIStream *ast;
646 st = s->streams[n];
647 ast = st->priv_data;
648
649 if( (st->discard >= AVDISCARD_DEFAULT && size==0)
650 /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & PKT_FLAG_KEY))*/ //FIXME needs a little reordering
651 || st->discard >= AVDISCARD_ALL){
652 if(ast->sample_size) ast->frame_offset += pkt->size;
653 else ast->frame_offset++;
654 url_fskip(pb, size);
655 goto resync;
656 }
657
658 if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
659 d[2]*256+d[3] == ast->prefix /*||
660 (d[2] == 'd' && d[3] == 'c') ||
661 (d[2] == 'w' && d[3] == 'b')*/) {
662
663//av_log(NULL, AV_LOG_DEBUG, "OK\n");
664 if(d[2]*256+d[3] == ast->prefix)
665 ast->prefix_count++;
666 else{
667 ast->prefix= d[2]*256+d[3];
668 ast->prefix_count= 0;
669 }
670
671 avi->stream_index= n;
672 ast->packet_size= size + 8;
673 ast->remaining= size;
674 goto resync;
675 }
676 }
677 /* palette changed chunk */
678 if ( d[0] >= '0' && d[0] <= '9'
679 && d[1] >= '0' && d[1] <= '9'
680 && ((d[2] == 'p' && d[3] == 'c'))
681 && n < s->nb_streams && i + size <= avi->movi_end) {
682
683 AVStream *st;
684 int first, clr, flags, k, p;
685
686 st = s->streams[n];
687
688 first = get_byte(pb);
689 clr = get_byte(pb);
690 if(!clr) /* all 256 colors used */
691 clr = 256;
692 flags = get_le16(pb);
693 p = 4;
694 for (k = first; k < clr + first; k++) {
695 int r, g, b;
696 r = get_byte(pb);
697 g = get_byte(pb);
698 b = get_byte(pb);
699 get_byte(pb);
700 st->codec->palctrl->palette[k] = b + (g << 8) + (r << 16);
701 }
702 st->codec->palctrl->palette_changed = 1;
703 goto resync;
704 }
705
706 }
707
708 return -1;
709}
710
711/* XXX: we make the implicit supposition that the position are sorted
712 for each stream */
713static int avi_read_idx1(AVFormatContext *s, int size)
714{
715 AVIContext *avi = s->priv_data;
716 ByteIOContext *pb = &s->pb;
717 int nb_index_entries, i;
718 AVStream *st;
719 AVIStream *ast;
720 unsigned int index, tag, flags, pos, len;
721 unsigned last_pos= -1;
722
723 nb_index_entries = size / 16;
724 if (nb_index_entries <= 0)
725 return -1;
726
727 /* read the entries and sort them in each stream component */
728 for(i = 0; i < nb_index_entries; i++) {
729 tag = get_le32(pb);
730 flags = get_le32(pb);
731 pos = get_le32(pb);
732 len = get_le32(pb);
733#if defined(DEBUG_SEEK)
734 av_log(NULL, AV_LOG_DEBUG, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
735 i, tag, flags, pos, len);
736#endif
737 if(i==0 && pos > avi->movi_list)
738 avi->movi_list= 0; //FIXME better check
739 pos += avi->movi_list;
740
741 index = ((tag & 0xff) - '0') * 10;
742 index += ((tag >> 8) & 0xff) - '0';
743 if (index >= s->nb_streams)
744 continue;
745 st = s->streams[index];
746 ast = st->priv_data;
747
748#if defined(DEBUG_SEEK)
749 av_log(NULL, AV_LOG_DEBUG, "%d cum_len=%d\n", len, ast->cum_len);
750#endif
751 if(last_pos == pos)
752 avi->non_interleaved= 1;
753 else
754 av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
755 if(ast->sample_size)
756 ast->cum_len += len / ast->sample_size;
757 else
758 ast->cum_len ++;
759 last_pos= pos;
760 }
761 return 0;
762}
763
764static int guess_ni_flag(AVFormatContext *s){
765 int i;
766 int64_t last_start=0;
767 int64_t first_end= INT64_MAX;
768
769 for(i=0; i<s->nb_streams; i++){
770 AVStream *st = s->streams[i];
771 int n= st->nb_index_entries;
772
773 if(n <= 0)
774 continue;
775
776 if(st->index_entries[0].pos > last_start)
777 last_start= st->index_entries[0].pos;
778 if(st->index_entries[n-1].pos < first_end)
779 first_end= st->index_entries[n-1].pos;
780 }
781 return last_start > first_end;
782}
783
784static int avi_load_index(AVFormatContext *s)
785{
786 AVIContext *avi = s->priv_data;
787 ByteIOContext *pb = &s->pb;
788 uint32_t tag, size;
789 offset_t pos= url_ftell(pb);
790
791 url_fseek(pb, avi->movi_end, SEEK_SET);
792#ifdef DEBUG_SEEK
793 printf("movi_end=0x%llx\n", avi->movi_end);
794#endif
795 for(;;) {
796 if (url_feof(pb))
797 break;
798 tag = get_le32(pb);
799 size = get_le32(pb);
800#ifdef DEBUG_SEEK
801 printf("tag=%c%c%c%c size=0x%x\n",
802 tag & 0xff,
803 (tag >> 8) & 0xff,
804 (tag >> 16) & 0xff,
805 (tag >> 24) & 0xff,
806 size);
807#endif
808 switch(tag) {
809 case MKTAG('i', 'd', 'x', '1'):
810 if (avi_read_idx1(s, size) < 0)
811 goto skip;
812 else
813 goto the_end;
814 break;
815 default:
816 skip:
817 size += (size & 1);
818 url_fskip(pb, size);
819 break;
820 }
821 }
822 the_end:
823 url_fseek(pb, pos, SEEK_SET);
824 return 0;
825}
826
827static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
828{
829 AVIContext *avi = s->priv_data;
830 AVStream *st;
831 int i, index;
832 int64_t pos;
833
834 if (!avi->index_loaded) {
835 /* we only load the index on demand */
836 avi_load_index(s);
837 avi->index_loaded = 1;
838 }
839 assert(stream_index>= 0);
840
841 st = s->streams[stream_index];
842 index= av_index_search_timestamp(st, timestamp, flags);
843 if(index<0)
844 return -1;
845
846 /* find the position */
847 pos = st->index_entries[index].pos;
848 timestamp = st->index_entries[index].timestamp;
849
850// av_log(NULL, AV_LOG_DEBUG, "XX %Ld %d %Ld\n", timestamp, index, st->index_entries[index].timestamp);
851
852 for(i = 0; i < s->nb_streams; i++) {
853 AVStream *st2 = s->streams[i];
854 AVIStream *ast2 = st2->priv_data;
855
856 ast2->packet_size=
857 ast2->remaining= 0;
858
859 if (st2->nb_index_entries <= 0)
860 continue;
861
862// assert(st2->codec->block_align);
863 assert(st2->time_base.den == ast2->rate);
864 assert(st2->time_base.num == ast2->scale);
865 index = av_index_search_timestamp(
866 st2,
867 av_rescale(timestamp, st2->time_base.den*(int64_t)st->time_base.num, st->time_base.den * (int64_t)st2->time_base.num),
868 flags | AVSEEK_FLAG_BACKWARD);
869 if(index<0)
870 index=0;
871
872 if(!avi->non_interleaved){
873 while(index>0 && st2->index_entries[index].pos > pos)
874 index--;
875 while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
876 index++;
877 }
878
879// av_log(NULL, AV_LOG_DEBUG, "%Ld %d %Ld\n", timestamp, index, st2->index_entries[index].timestamp);
880 /* extract the current frame number */
881 ast2->frame_offset = st2->index_entries[index].timestamp;
882 if(ast2->sample_size)
883 ast2->frame_offset *=ast2->sample_size;
884 }
885
886 if (avi->dv_demux)
887 dv_flush_audio_packets(avi->dv_demux);
888 /* do the seek */
889 url_fseek(&s->pb, pos, SEEK_SET);
890 avi->stream_index= -1;
891 return 0;
892}
893
894static int avi_read_close(AVFormatContext *s)
895{
896 int i;
897 AVIContext *avi = s->priv_data;
898
899 for(i=0;i<s->nb_streams;i++) {
900 AVStream *st = s->streams[i];
901 AVIStream *ast = st->priv_data;
902 av_free(ast);
903 av_free(st->codec->palctrl);
904 }
905
906 if (avi->dv_demux)
907 av_free(avi->dv_demux);
908
909 return 0;
910}
911
912static int avi_probe(AVProbeData *p)
913{
914 /* check file header */
915 if (p->buf_size <= 32)
916 return 0;
917 if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
918 p->buf[2] == 'F' && p->buf[3] == 'F' &&
919 p->buf[8] == 'A' && p->buf[9] == 'V' &&
920 p->buf[10] == 'I' && p->buf[11] == ' ')
921 return AVPROBE_SCORE_MAX;
922 else
923 return 0;
924}
925
926static AVInputFormat avi_demuxer = {
927 "avi",
928 "avi format",
929 sizeof(AVIContext),
930 avi_probe,
931 avi_read_header,
932 avi_read_packet,
933 avi_read_close,
934 avi_read_seek,
935};
936
937int avidec_init(void)
938{
939 av_register_input_format(&avi_demuxer);
940 return 0;
941}
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