3 * Copyright (c) 2001 Fabrice Bellard
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/mathematics.h"
24 #include "libavutil/bswap.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/avstring.h"
28 #include "libavutil/avassert.h"
35 typedef struct AVIStream {
36 int64_t frame_offset; /* current frame (video) or byte (audio) counter
37 (used to compute the pts) */
43 int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
45 int64_t cum_len; /* temporary storage (used during seek) */
47 int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
51 int dshow_block_align; ///< block align variable used to emulate bugs in the MS dshow demuxer
53 AVFormatContext *sub_ctx;
71 DVDemuxContext* dv_demux;
74 #define MAX_ODML_DEPTH 1000
79 static const AVOption options[] = {
80 { "use_odml", "use odml index", offsetof(AVIContext, use_odml), AV_OPT_TYPE_INT, {.i64 = 1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM},
84 static const AVClass demuxer_class = {
86 .item_name = av_default_item_name,
88 .version = LIBAVUTIL_VERSION_INT,
89 .category = AV_CLASS_CATEGORY_DEMUXER,
93 static const char avi_headers[][8] = {
94 { 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' ' },
95 { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X' },
96 { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19},
97 { 'O', 'N', '2', ' ', 'O', 'N', '2', 'f' },
98 { 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' ' },
102 static const AVMetadataConv avi_metadata_conv[] = {
107 static int avi_load_index(AVFormatContext *s);
108 static int guess_ni_flag(AVFormatContext *s);
110 #define print_tag(str, tag, size) \
111 av_dlog(NULL, "%s: tag=%c%c%c%c size=0x%x\n", \
114 (tag >> 16) & 0xff, \
115 (tag >> 24) & 0xff, \
118 static inline int get_duration(AVIStream *ast, int len){
119 if(ast->sample_size){
121 }else if (ast->dshow_block_align){
122 return (len + ast->dshow_block_align - 1)/ast->dshow_block_align;
127 static int get_riff(AVFormatContext *s, AVIOContext *pb)
129 AVIContext *avi = s->priv_data;
133 /* check RIFF header */
134 avio_read(pb, header, 4);
135 avi->riff_end = avio_rl32(pb); /* RIFF chunk size */
136 avi->riff_end += avio_tell(pb); /* RIFF chunk end */
137 avio_read(pb, header+4, 4);
139 for(i=0; avi_headers[i][0]; i++)
140 if(!memcmp(header, avi_headers[i], 8))
142 if(!avi_headers[i][0])
145 if(header[7] == 0x19)
146 av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");
151 static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
152 AVIContext *avi = s->priv_data;
153 AVIOContext *pb = s->pb;
154 int longs_pre_entry= avio_rl16(pb);
155 int index_sub_type = avio_r8(pb);
156 int index_type = avio_r8(pb);
157 int entries_in_use = avio_rl32(pb);
158 int chunk_id = avio_rl32(pb);
159 int64_t base = avio_rl64(pb);
160 int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
164 int64_t last_pos= -1;
165 int64_t filesize= avi->fsize;
167 av_dlog(s, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",
168 longs_pre_entry,index_type, entries_in_use, chunk_id, base);
170 if(stream_id >= s->nb_streams || stream_id < 0)
172 st= s->streams[stream_id];
180 if(index_type && longs_pre_entry != 2)
185 if(filesize > 0 && base >= filesize){
186 av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
187 if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)
193 for(i=0; i<entries_in_use; i++){
195 int64_t pos= avio_rl32(pb) + base - 8;
196 int len = avio_rl32(pb);
201 av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);
206 if(last_pos == pos || pos == base - 8)
207 avi->non_interleaved= 1;
208 if(last_pos != pos && (len || !ast->sample_size))
209 av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
211 ast->cum_len += get_duration(ast, len);
216 offset = avio_rl64(pb);
217 avio_rl32(pb); /* size */
218 duration = avio_rl32(pb);
225 if(avi->odml_depth > MAX_ODML_DEPTH){
226 av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");
230 if(avio_seek(pb, offset+8, SEEK_SET) < 0)
233 read_braindead_odml_indx(s, frame_num);
235 frame_num += duration;
237 if(avio_seek(pb, pos, SEEK_SET) < 0) {
238 av_log(s, AV_LOG_ERROR, "Failed to restore position after reading index\n");
248 static void clean_index(AVFormatContext *s){
252 for(i=0; i<s->nb_streams; i++){
253 AVStream *st = s->streams[i];
254 AVIStream *ast = st->priv_data;
255 int n= st->nb_index_entries;
256 int max= ast->sample_size;
257 int64_t pos, size, ts;
259 if(n != 1 || ast->sample_size==0)
262 while(max < 1024) max+=max;
264 pos= st->index_entries[0].pos;
265 size= st->index_entries[0].size;
266 ts= st->index_entries[0].timestamp;
268 for(j=0; j<size; j+=max){
269 av_add_index_entry(st, pos+j, ts+j, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
274 static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag, uint32_t size)
276 AVIOContext *pb = s->pb;
277 char key[5] = {0}, *value;
281 if (size == UINT_MAX)
283 value = av_malloc(size+1);
286 avio_read(pb, value, size);
291 return av_dict_set(st ? &st->metadata : &s->metadata, key, value,
292 AV_DICT_DONT_STRDUP_VAL);
295 static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
296 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
298 static void avi_metadata_creation_time(AVDictionary **metadata, char *date)
300 char month[4], time[9], buffer[64];
302 /* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */
303 if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",
304 month, &day, time, &year) == 4) {
306 if (!av_strcasecmp(month, months[i])) {
307 snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",
308 year, i+1, day, time);
309 av_dict_set(metadata, "creation_time", buffer, 0);
311 } else if (date[4] == '/' && date[7] == '/') {
312 date[4] = date[7] = '-';
313 av_dict_set(metadata, "creation_time", date, 0);
317 static void avi_read_nikon(AVFormatContext *s, uint64_t end)
319 while (avio_tell(s->pb) < end) {
320 uint32_t tag = avio_rl32(s->pb);
321 uint32_t size = avio_rl32(s->pb);
323 case MKTAG('n', 'c', 't', 'g'): { /* Nikon Tags */
324 uint64_t tag_end = avio_tell(s->pb) + size;
325 while (avio_tell(s->pb) < tag_end) {
326 uint16_t tag = avio_rl16(s->pb);
327 uint16_t size = avio_rl16(s->pb);
328 const char *name = NULL;
329 char buffer[64] = {0};
330 size -= avio_read(s->pb, buffer,
331 FFMIN(size, sizeof(buffer)-1));
333 case 0x03: name = "maker"; break;
334 case 0x04: name = "model"; break;
335 case 0x13: name = "creation_time";
336 if (buffer[4] == ':' && buffer[7] == ':')
337 buffer[4] = buffer[7] = '-';
341 av_dict_set(&s->metadata, name, buffer, 0);
342 avio_skip(s->pb, size);
347 avio_skip(s->pb, size);
353 static int avi_read_header(AVFormatContext *s)
355 AVIContext *avi = s->priv_data;
356 AVIOContext *pb = s->pb;
357 unsigned int tag, tag1, handler;
358 int codec_type, stream_index, frame_period;
362 AVIStream *ast = NULL;
363 int avih_width=0, avih_height=0;
364 int amv_file_format=0;
365 uint64_t list_end = 0;
368 avi->stream_index= -1;
370 if (get_riff(s, pb) < 0)
373 av_log(avi, AV_LOG_DEBUG, "use odml:%d\n", avi->use_odml);
375 avi->fsize = avio_size(pb);
376 if(avi->fsize<=0 || avi->fsize < avi->riff_end)
377 avi->fsize= avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
387 size = avio_rl32(pb);
389 print_tag("tag", tag, size);
392 case MKTAG('L', 'I', 'S', 'T'):
393 list_end = avio_tell(pb) + size;
394 /* Ignored, except at start of video packets. */
395 tag1 = avio_rl32(pb);
397 print_tag("list", tag1, 0);
399 if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
400 avi->movi_list = avio_tell(pb) - 4;
401 if(size) avi->movi_end = avi->movi_list + size + (size & 1);
402 else avi->movi_end = avi->fsize;
403 av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);
406 else if (tag1 == MKTAG('I', 'N', 'F', 'O'))
407 ff_read_riff_info(s, size - 4);
408 else if (tag1 == MKTAG('n', 'c', 'd', 't'))
409 avi_read_nikon(s, list_end);
412 case MKTAG('I', 'D', 'I', 'T'): {
413 unsigned char date[64] = {0};
415 size -= avio_read(pb, date, FFMIN(size, sizeof(date)-1));
417 avi_metadata_creation_time(&s->metadata, date);
420 case MKTAG('d', 'm', 'l', 'h'):
422 avio_skip(pb, size + (size & 1));
424 case MKTAG('a', 'm', 'v', 'h'):
426 case MKTAG('a', 'v', 'i', 'h'):
428 /* using frame_period is bad idea */
429 frame_period = avio_rl32(pb);
430 avio_rl32(pb); /* max. bytes per second */
432 avi->non_interleaved |= avio_rl32(pb) & AVIF_MUSTUSEINDEX;
434 avio_skip(pb, 2 * 4);
437 avih_width=avio_rl32(pb);
438 avih_height=avio_rl32(pb);
440 avio_skip(pb, size - 10 * 4);
442 case MKTAG('s', 't', 'r', 'h'):
445 tag1 = avio_rl32(pb);
446 handler = avio_rl32(pb); /* codec tag */
448 if(tag1 == MKTAG('p', 'a', 'd', 's')){
449 avio_skip(pb, size - 8);
453 st = avformat_new_stream(s, NULL);
457 st->id = stream_index;
458 ast = av_mallocz(sizeof(AVIStream));
464 tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');
466 print_tag("strh", tag1, -1);
468 if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
472 * After some consideration -- I don't think we
473 * have to support anything but DV in type1 AVIs.
475 if (s->nb_streams != 1)
478 if (handler != MKTAG('d', 'v', 's', 'd') &&
479 handler != MKTAG('d', 'v', 'h', 'd') &&
480 handler != MKTAG('d', 'v', 's', 'l'))
483 ast = s->streams[0]->priv_data;
484 av_freep(&s->streams[0]->codec->extradata);
485 av_freep(&s->streams[0]->codec);
486 av_freep(&s->streams[0]->info);
487 av_freep(&s->streams[0]);
489 if (CONFIG_DV_DEMUXER) {
490 avi->dv_demux = avpriv_dv_init_demux(s);
494 s->streams[0]->priv_data = ast;
495 avio_skip(pb, 3 * 4);
496 ast->scale = avio_rl32(pb);
497 ast->rate = avio_rl32(pb);
498 avio_skip(pb, 4); /* start time */
500 dv_dur = avio_rl32(pb);
501 if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
502 dv_dur *= AV_TIME_BASE;
503 s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
506 * else, leave duration alone; timing estimation in utils.c
507 * will make a guess based on bitrate.
510 stream_index = s->nb_streams - 1;
511 avio_skip(pb, size - 9*4);
515 av_assert0(stream_index < s->nb_streams);
516 st->codec->stream_codec_tag= handler;
518 avio_rl32(pb); /* flags */
519 avio_rl16(pb); /* priority */
520 avio_rl16(pb); /* language */
521 avio_rl32(pb); /* initial frame */
522 ast->scale = avio_rl32(pb);
523 ast->rate = avio_rl32(pb);
524 if(!(ast->scale && ast->rate)){
525 av_log(s, AV_LOG_WARNING, "scale/rate is %u/%u which is invalid. (This file has been generated by broken software.)\n", ast->scale, ast->rate);
528 ast->scale = frame_period;
534 avpriv_set_pts_info(st, 64, ast->scale, ast->rate);
536 ast->cum_len=avio_rl32(pb); /* start */
537 st->nb_frames = avio_rl32(pb);
540 avio_rl32(pb); /* buffer size */
541 avio_rl32(pb); /* quality */
542 if (ast->cum_len*ast->scale/ast->rate > 3600) {
543 av_log(s, AV_LOG_ERROR, "crazy start time, iam scared, giving up\n");
544 return AVERROR_INVALIDDATA;
546 ast->sample_size = avio_rl32(pb); /* sample ssize */
547 ast->cum_len *= FFMAX(1, ast->sample_size);
548 av_dlog(s, "%"PRIu32" %"PRIu32" %d\n",
549 ast->rate, ast->scale, ast->sample_size);
552 case MKTAG('v', 'i', 'd', 's'):
553 codec_type = AVMEDIA_TYPE_VIDEO;
555 ast->sample_size = 0;
557 case MKTAG('a', 'u', 'd', 's'):
558 codec_type = AVMEDIA_TYPE_AUDIO;
560 case MKTAG('t', 'x', 't', 's'):
561 codec_type = AVMEDIA_TYPE_SUBTITLE;
563 case MKTAG('d', 'a', 't', 's'):
564 codec_type = AVMEDIA_TYPE_DATA;
567 av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);
569 if(ast->sample_size == 0)
570 st->duration = st->nb_frames;
571 ast->frame_offset= ast->cum_len;
572 avio_skip(pb, size - 12 * 4);
574 case MKTAG('s', 't', 'r', 'f'):
578 if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
581 uint64_t cur_pos = avio_tell(pb);
583 if (cur_pos < list_end)
584 size = FFMIN(size, list_end - cur_pos);
585 st = s->streams[stream_index];
587 case AVMEDIA_TYPE_VIDEO:
589 st->codec->width=avih_width;
590 st->codec->height=avih_height;
591 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
592 st->codec->codec_id = AV_CODEC_ID_AMV;
596 tag1 = ff_get_bmp_header(pb, st, &esize);
598 if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {
599 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
600 st->codec->codec_tag = tag1;
601 st->codec->codec_id = AV_CODEC_ID_XSUB;
605 if(size > 10*4 && size<(1<<30) && size < avi->fsize){
606 if(esize == size-1 && (esize&1)) st->codec->extradata_size= esize - 10*4;
607 else st->codec->extradata_size= size - 10*4;
608 st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
609 if (!st->codec->extradata) {
610 st->codec->extradata_size= 0;
611 return AVERROR(ENOMEM);
613 avio_read(pb, st->codec->extradata, st->codec->extradata_size);
616 if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
619 /* Extract palette from extradata if bpp <= 8. */
620 /* This code assumes that extradata contains only palette. */
621 /* This is true for all paletted codecs implemented in FFmpeg. */
622 if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {
623 int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
624 const uint8_t *pal_src;
626 pal_size = FFMIN(pal_size, st->codec->extradata_size);
627 pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;
628 for (i = 0; i < pal_size/4; i++)
629 ast->pal[i] = 0xFF<<24 | AV_RL32(pal_src+4*i);
633 print_tag("video", tag1, 0);
635 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
636 st->codec->codec_tag = tag1;
637 st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tag1);
638 st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.
640 if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){
641 st->codec->extradata_size+= 9;
642 st->codec->extradata= av_realloc_f(st->codec->extradata, 1, st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
643 if(st->codec->extradata)
644 memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);
646 st->codec->height= FFABS(st->codec->height);
648 // avio_skip(pb, size - 5 * 4);
650 case AVMEDIA_TYPE_AUDIO:
651 ret = ff_get_wav_header(pb, st->codec, size);
654 ast->dshow_block_align= st->codec->block_align;
655 if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){
656 av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);
657 ast->sample_size= st->codec->block_align;
659 if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
661 /* Force parsing as several audio frames can be in
662 * one packet and timestamps refer to packet start. */
663 st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;
664 /* ADTS header is in extradata, AAC without header must be
665 * stored as exact frames. Parser not needed and it will
667 if (st->codec->codec_id == AV_CODEC_ID_AAC && st->codec->extradata_size)
668 st->need_parsing = AVSTREAM_PARSE_NONE;
669 /* AVI files with Xan DPCM audio (wrongly) declare PCM
670 * audio in the header but have Axan as stream_code_tag. */
671 if (st->codec->stream_codec_tag == AV_RL32("Axan")){
672 st->codec->codec_id = AV_CODEC_ID_XAN_DPCM;
673 st->codec->codec_tag = 0;
674 ast->dshow_block_align = 0;
676 if (amv_file_format){
677 st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_AMV;
678 ast->dshow_block_align = 0;
680 if(st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align <= 4 && ast->dshow_block_align) {
681 av_log(s, AV_LOG_DEBUG, "overriding invalid dshow_block_align of %d\n", ast->dshow_block_align);
682 ast->dshow_block_align = 0;
684 if(st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 1024 && ast->sample_size == 1024 ||
685 st->codec->codec_id == AV_CODEC_ID_MP3 && ast->dshow_block_align == 1152 && ast->sample_size == 1152) {
686 av_log(s, AV_LOG_DEBUG, "overriding sample_size\n");
687 ast->sample_size = 0;
690 case AVMEDIA_TYPE_SUBTITLE:
691 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
692 st->request_probe= 1;
695 st->codec->codec_type = AVMEDIA_TYPE_DATA;
696 st->codec->codec_id= AV_CODEC_ID_NONE;
697 st->codec->codec_tag= 0;
703 case MKTAG('s', 't', 'r', 'd'):
704 if (stream_index >= (unsigned)s->nb_streams || s->streams[stream_index]->codec->extradata_size) {
707 uint64_t cur_pos = avio_tell(pb);
708 if (cur_pos < list_end)
709 size = FFMIN(size, list_end - cur_pos);
710 st = s->streams[stream_index];
713 st->codec->extradata_size= size;
714 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
715 if (!st->codec->extradata) {
716 st->codec->extradata_size= 0;
717 return AVERROR(ENOMEM);
719 avio_read(pb, st->codec->extradata, st->codec->extradata_size);
722 if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
726 case MKTAG('i', 'n', 'd', 'x'):
728 if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) && avi->use_odml &&
729 read_braindead_odml_indx(s, 0) < 0 && (s->error_recognition & AV_EF_EXPLODE))
731 avio_seek(pb, i+size, SEEK_SET);
733 case MKTAG('v', 'p', 'r', 'p'):
734 if(stream_index < (unsigned)s->nb_streams && size > 9*4){
735 AVRational active, active_aspect;
737 st = s->streams[stream_index];
744 active_aspect.den= avio_rl16(pb);
745 active_aspect.num= avio_rl16(pb);
746 active.num = avio_rl32(pb);
747 active.den = avio_rl32(pb);
748 avio_rl32(pb); //nbFieldsPerFrame
750 if(active_aspect.num && active_aspect.den && active.num && active.den){
751 st->sample_aspect_ratio= av_div_q(active_aspect, active);
752 av_dlog(s, "vprp %d/%d %d/%d\n",
753 active_aspect.num, active_aspect.den,
754 active.num, active.den);
760 case MKTAG('s', 't', 'r', 'n'):
762 avi_read_tag(s, s->streams[s->nb_streams-1], tag, size);
767 av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "
768 "I will ignore it and try to continue anyway.\n");
769 if (s->error_recognition & AV_EF_EXPLODE)
771 avi->movi_list = avio_tell(pb) - 4;
772 avi->movi_end = avi->fsize;
782 /* check stream number */
783 if (stream_index != s->nb_streams - 1) {
788 if(!avi->index_loaded && pb->seekable)
790 avi->index_loaded |= 1;
791 avi->non_interleaved |= guess_ni_flag(s) | (s->flags & AVFMT_FLAG_SORT_DTS);
792 for(i=0; i<s->nb_streams; i++){
793 AVStream *st = s->streams[i];
794 if(st->nb_index_entries)
797 // DV-in-AVI cannot be non-interleaved, if set this must be
800 avi->non_interleaved=0;
801 if(i==s->nb_streams && avi->non_interleaved) {
802 av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");
803 avi->non_interleaved=0;
806 if(avi->non_interleaved) {
807 av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
811 ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
812 ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);
817 static int read_gab2_sub(AVStream *st, AVPacket *pkt) {
818 if (!strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data+5) == 2) {
820 int score = AVPROBE_SCORE_MAX / 2, ret;
821 AVIStream *ast = st->priv_data;
822 AVInputFormat *sub_demuxer;
823 AVRational time_base;
824 AVIOContext *pb = avio_alloc_context( pkt->data + 7,
826 0, NULL, NULL, NULL, NULL);
828 unsigned int desc_len = avio_rl32(pb);
830 if (desc_len > pb->buf_end - pb->buf_ptr)
833 ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
834 avio_skip(pb, desc_len - ret);
836 av_dict_set(&st->metadata, "title", desc, 0);
838 avio_rl16(pb); /* flags? */
839 avio_rl32(pb); /* data size */
841 pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };
842 if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))
845 if (!(ast->sub_ctx = avformat_alloc_context()))
848 ast->sub_ctx->pb = pb;
849 if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
850 ff_read_packet(ast->sub_ctx, &ast->sub_pkt);
851 *st->codec = *ast->sub_ctx->streams[0]->codec;
852 ast->sub_ctx->streams[0]->codec->extradata = NULL;
853 time_base = ast->sub_ctx->streams[0]->time_base;
854 avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
856 ast->sub_buffer = pkt->data;
857 memset(pkt, 0, sizeof(*pkt));
865 static AVStream *get_subtitle_pkt(AVFormatContext *s, AVStream *next_st,
868 AVIStream *ast, *next_ast = next_st->priv_data;
869 int64_t ts, next_ts, ts_min = INT64_MAX;
870 AVStream *st, *sub_st = NULL;
873 next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
876 for (i=0; i<s->nb_streams; i++) {
879 if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
880 ts = av_rescale_q(ast->sub_pkt.dts, st->time_base, AV_TIME_BASE_Q);
881 if (ts <= next_ts && ts < ts_min) {
889 ast = sub_st->priv_data;
891 pkt->stream_index = sub_st->index;
892 if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
893 ast->sub_pkt.data = NULL;
898 static int get_stream_idx(int *d){
899 if( d[0] >= '0' && d[0] <= '9'
900 && d[1] >= '0' && d[1] <= '9'){
901 return (d[0] - '0') * 10 + (d[1] - '0');
903 return 100; //invalid stream ID
909 * @param exit_early set to 1 to just gather packet position without making the changes needed to actually read & return the packet
911 static int avi_sync(AVFormatContext *s, int exit_early)
913 AVIContext *avi = s->priv_data;
914 AVIOContext *pb = s->pb;
921 memset(d, -1, sizeof(d));
922 for(i=sync=avio_tell(pb); !url_feof(pb); i++) {
929 size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
931 n= get_stream_idx(d+2);
932 av_dlog(s, "%X %X %X %X %X %X %X %X %"PRId64" %u %d\n",
933 d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
934 if(i + (uint64_t)size > avi->fsize || d[0] > 127)
938 if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
940 ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')
941 ||(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')){
947 if(d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T'){
952 n= get_stream_idx(d);
954 if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)
957 //detect ##ix chunk and skip
958 if(d[2] == 'i' && d[3] == 'x' && n < s->nb_streams){
964 if(n < s->nb_streams){
971 av_log(s, AV_LOG_WARNING, "Skiping foreign stream %d packet\n", n);
975 if(s->nb_streams>=2){
976 AVStream *st1 = s->streams[1];
977 AVIStream *ast1= st1->priv_data;
978 //workaround for broken small-file-bug402.avi
979 if( d[2] == 'w' && d[3] == 'b'
981 && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO
982 && st1->codec->codec_type == AVMEDIA_TYPE_AUDIO
983 && ast->prefix == 'd'*256+'c'
984 && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
989 av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");
994 if( (st->discard >= AVDISCARD_DEFAULT && size==0)
995 /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & AV_PKT_FLAG_KEY))*/ //FIXME needs a little reordering
996 || st->discard >= AVDISCARD_ALL){
998 ast->frame_offset += get_duration(ast, size);
1000 avio_skip(pb, size);
1004 if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {
1005 int k = avio_r8(pb);
1006 int last = (k + avio_r8(pb) - 1) & 0xFF;
1008 avio_rl16(pb); //flags
1010 for (; k <= last; k++)
1011 ast->pal[k] = 0xFF<<24 | avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);
1014 } else if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
1015 d[2]*256+d[3] == ast->prefix /*||
1016 (d[2] == 'd' && d[3] == 'c') ||
1017 (d[2] == 'w' && d[3] == 'b')*/) {
1021 if(d[2]*256+d[3] == ast->prefix)
1022 ast->prefix_count++;
1024 ast->prefix= d[2]*256+d[3];
1025 ast->prefix_count= 0;
1028 avi->stream_index= n;
1029 ast->packet_size= size + 8;
1030 ast->remaining= size;
1032 if(size || !ast->sample_size){
1033 uint64_t pos= avio_tell(pb) - 8;
1034 if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){
1035 av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);
1048 static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
1050 AVIContext *avi = s->priv_data;
1051 AVIOContext *pb = s->pb;
1055 if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1056 int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
1061 if(avi->non_interleaved){
1062 int best_stream_index = 0;
1063 AVStream *best_st= NULL;
1064 AVIStream *best_ast;
1065 int64_t best_ts= INT64_MAX;
1068 for(i=0; i<s->nb_streams; i++){
1069 AVStream *st = s->streams[i];
1070 AVIStream *ast = st->priv_data;
1071 int64_t ts= ast->frame_offset;
1074 if(!st->nb_index_entries)
1077 last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
1078 if(!ast->remaining && ts > last_ts)
1081 ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});
1083 av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,
1084 st->time_base.num, st->time_base.den, ast->frame_offset);
1088 best_stream_index= i;
1094 best_ast = best_st->priv_data;
1095 best_ts = best_ast->frame_offset;
1096 if(best_ast->remaining)
1097 i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
1099 i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
1101 best_ast->frame_offset= best_st->index_entries[i].timestamp;
1105 int64_t pos= best_st->index_entries[i].pos;
1106 pos += best_ast->packet_size - best_ast->remaining;
1107 if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)
1110 av_assert0(best_ast->remaining <= best_ast->packet_size);
1112 avi->stream_index= best_stream_index;
1113 if(!best_ast->remaining)
1114 best_ast->packet_size=
1115 best_ast->remaining= best_st->index_entries[i].size;
1122 if(avi->stream_index >= 0){
1123 AVStream *st= s->streams[ avi->stream_index ];
1124 AVIStream *ast= st->priv_data;
1127 if(get_subtitle_pkt(s, st, pkt))
1130 if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
1132 else if(ast->sample_size < 32)
1133 // arbitrary multiplier to avoid tiny packets for raw PCM data
1134 size= 1024*ast->sample_size;
1136 size= ast->sample_size;
1138 if(size > ast->remaining)
1139 size= ast->remaining;
1140 avi->last_pkt_pos= avio_tell(pb);
1141 err= av_get_packet(pb, pkt, size);
1146 if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){
1148 pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);
1150 av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");
1152 memcpy(pal, ast->pal, AVPALETTE_SIZE);
1157 if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1158 dstr = pkt->destruct;
1159 size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
1160 pkt->data, pkt->size, pkt->pos);
1161 pkt->destruct = dstr;
1162 pkt->flags |= AV_PKT_FLAG_KEY;
1164 av_free_packet(pkt);
1165 } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE
1166 && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {
1167 ast->frame_offset++;
1168 avi->stream_index = -1;
1172 /* XXX: How to handle B-frames in AVI? */
1173 pkt->dts = ast->frame_offset;
1174 // pkt->dts += ast->start;
1175 if(ast->sample_size)
1176 pkt->dts /= ast->sample_size;
1177 av_dlog(s, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n",
1178 pkt->dts, ast->frame_offset, ast->scale, ast->rate,
1179 ast->sample_size, AV_TIME_BASE, avi->stream_index, size);
1180 pkt->stream_index = avi->stream_index;
1182 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
1185 av_assert0(st->index_entries);
1187 index= av_index_search_timestamp(st, ast->frame_offset, 0);
1188 e= &st->index_entries[index];
1190 if(index >= 0 && e->timestamp == ast->frame_offset){
1191 if (index == st->nb_index_entries-1){
1195 for(i=0; i<FFMIN(size,256); i++){
1196 if(st->codec->codec_id == AV_CODEC_ID_MPEG4){
1198 key= !(pkt->data[i]&0xC0);
1203 state= (state<<8) + pkt->data[i];
1206 e->flags &= ~AVINDEX_KEYFRAME;
1208 if (e->flags & AVINDEX_KEYFRAME)
1209 pkt->flags |= AV_PKT_FLAG_KEY;
1212 pkt->flags |= AV_PKT_FLAG_KEY;
1214 ast->frame_offset += get_duration(ast, pkt->size);
1216 ast->remaining -= err;
1217 if(!ast->remaining){
1218 avi->stream_index= -1;
1219 ast->packet_size= 0;
1222 if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){
1223 av_free_packet(pkt);
1228 if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){
1229 int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);
1231 if(avi->dts_max - dts > 2*AV_TIME_BASE){
1232 avi->non_interleaved= 1;
1233 av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");
1234 }else if(avi->dts_max < dts)
1241 if ((err = avi_sync(s, 0)) < 0)
1246 /* XXX: We make the implicit supposition that the positions are sorted
1248 static int avi_read_idx1(AVFormatContext *s, int size)
1250 AVIContext *avi = s->priv_data;
1251 AVIOContext *pb = s->pb;
1252 int nb_index_entries, i;
1255 unsigned int index, tag, flags, pos, len, first_packet = 1;
1256 unsigned last_pos= -1;
1257 unsigned last_idx= -1;
1258 int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
1261 nb_index_entries = size / 16;
1262 if (nb_index_entries <= 0)
1265 idx1_pos = avio_tell(pb);
1266 avio_seek(pb, avi->movi_list+4, SEEK_SET);
1267 if (avi_sync(s, 1) == 0) {
1268 first_packet_pos = avio_tell(pb) - 8;
1270 avi->stream_index = -1;
1271 avio_seek(pb, idx1_pos, SEEK_SET);
1273 /* Read the entries and sort them in each stream component. */
1274 for(i = 0; i < nb_index_entries; i++) {
1278 tag = avio_rl32(pb);
1279 flags = avio_rl32(pb);
1280 pos = avio_rl32(pb);
1281 len = avio_rl32(pb);
1282 av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
1283 i, tag, flags, pos, len);
1285 index = ((tag & 0xff) - '0') * 10;
1286 index += ((tag >> 8) & 0xff) - '0';
1287 if (index >= s->nb_streams)
1289 st = s->streams[index];
1290 ast = st->priv_data;
1292 if(first_packet && first_packet_pos && len) {
1293 data_offset = first_packet_pos - pos;
1298 av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
1301 // even if we have only a single stream, we should
1302 // switch to non-interleaved to get correct timestamps
1304 avi->non_interleaved= 1;
1305 if(last_idx != pos && len) {
1306 av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
1309 ast->cum_len += get_duration(ast, len);
1311 anykey |= flags&AVIIF_INDEX;
1314 for (index = 0; index < s->nb_streams; index++) {
1315 st = s->streams[index];
1316 if (st->nb_index_entries)
1317 st->index_entries[0].flags |= AVINDEX_KEYFRAME;
1323 static int guess_ni_flag(AVFormatContext *s){
1325 int64_t last_start=0;
1326 int64_t first_end= INT64_MAX;
1327 int64_t oldpos= avio_tell(s->pb);
1329 int64_t min_pos, pos;
1331 for(i=0; i<s->nb_streams; i++){
1332 AVStream *st = s->streams[i];
1333 int n= st->nb_index_entries;
1340 int64_t pos= st->index_entries[0].pos;
1341 avio_seek(s->pb, pos + 4, SEEK_SET);
1342 size= avio_rl32(s->pb);
1343 if(pos + size > st->index_entries[1].pos)
1344 last_start= INT64_MAX;
1347 if(st->index_entries[0].pos > last_start)
1348 last_start= st->index_entries[0].pos;
1349 if(st->index_entries[n-1].pos < first_end)
1350 first_end= st->index_entries[n-1].pos;
1352 avio_seek(s->pb, oldpos, SEEK_SET);
1353 if (last_start > first_end)
1355 idx= av_mallocz(sizeof(*idx) * s->nb_streams);
1356 for (min_pos=pos=0; min_pos!=INT64_MAX; pos= min_pos+1LU) {
1357 int64_t max_dts = INT64_MIN/2, min_dts= INT64_MAX/2;
1358 min_pos = INT64_MAX;
1360 for (i=0; i<s->nb_streams; i++) {
1361 AVStream *st = s->streams[i];
1362 int n= st->nb_index_entries;
1363 while (idx[i]<n && st->index_entries[idx[i]].pos < pos)
1366 min_dts = FFMIN(min_dts, av_rescale_q(st->index_entries[idx[i]].timestamp, st->time_base, AV_TIME_BASE_Q));
1367 min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
1370 max_dts = FFMAX(max_dts, av_rescale_q(st->index_entries[idx[i]-1].timestamp, st->time_base, AV_TIME_BASE_Q));
1372 if(max_dts - min_dts > 2*AV_TIME_BASE) {
1381 static int avi_load_index(AVFormatContext *s)
1383 AVIContext *avi = s->priv_data;
1384 AVIOContext *pb = s->pb;
1386 int64_t pos= avio_tell(pb);
1390 if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
1391 goto the_end; // maybe truncated file
1392 av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
1394 tag = avio_rl32(pb);
1395 size = avio_rl32(pb);
1398 next = avio_tell(pb) + size + (size & 1);
1400 av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
1407 if (tag == MKTAG('i', 'd', 'x', '1') &&
1408 avi_read_idx1(s, size) >= 0) {
1409 avi->index_loaded=2;
1411 }else if(tag == MKTAG('L', 'I', 'S', 'T')) {
1412 uint32_t tag1 = avio_rl32(pb);
1414 if (tag1 == MKTAG('I', 'N', 'F', 'O'))
1415 ff_read_riff_info(s, size - 4);
1419 if (avio_seek(pb, next, SEEK_SET) < 0)
1420 break; // something is wrong here
1423 avio_seek(pb, pos, SEEK_SET);
1427 static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
1429 AVIStream *ast2 = st2->priv_data;
1430 int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
1431 av_free_packet(&ast2->sub_pkt);
1432 if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
1433 avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
1434 ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
1437 static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
1439 AVIContext *avi = s->priv_data;
1442 int64_t pos, pos_min;
1445 if (!avi->index_loaded) {
1446 /* we only load the index on demand */
1448 avi->index_loaded |= 1;
1450 av_assert0(stream_index>= 0);
1452 st = s->streams[stream_index];
1454 index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);
1456 if (st->nb_index_entries > 0)
1457 av_log(s, AV_LOG_DEBUG, "Failed to find timestamp %"PRId64 " in index %"PRId64 " .. %"PRId64 "\n",
1458 timestamp * FFMAX(ast->sample_size, 1),
1459 st->index_entries[0].timestamp,
1460 st->index_entries[st->nb_index_entries - 1].timestamp);
1464 /* find the position */
1465 pos = st->index_entries[index].pos;
1466 timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
1468 av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",
1469 timestamp, index, st->index_entries[index].timestamp);
1471 if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1472 /* One and only one real stream for DV in AVI, and it has video */
1473 /* offsets. Calling with other stream indexes should have failed */
1474 /* the av_index_search_timestamp call above. */
1475 av_assert0(stream_index == 0);
1477 if(avio_seek(s->pb, pos, SEEK_SET) < 0)
1480 /* Feed the DV video stream version of the timestamp to the */
1481 /* DV demux so it can synthesize correct timestamps. */
1482 ff_dv_offset_reset(avi->dv_demux, timestamp);
1484 avi->stream_index= -1;
1489 for(i = 0; i < s->nb_streams; i++) {
1490 AVStream *st2 = s->streams[i];
1491 AVIStream *ast2 = st2->priv_data;
1496 if (ast2->sub_ctx) {
1497 seek_subtitle(st, st2, timestamp);
1501 if (st2->nb_index_entries <= 0)
1504 // av_assert1(st2->codec->block_align);
1505 av_assert0((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);
1506 index = av_index_search_timestamp(
1508 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1509 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));
1512 ast2->seek_pos= st2->index_entries[index].pos;
1513 pos_min= FFMIN(pos_min,ast2->seek_pos);
1515 for(i = 0; i < s->nb_streams; i++) {
1516 AVStream *st2 = s->streams[i];
1517 AVIStream *ast2 = st2->priv_data;
1519 if (ast2->sub_ctx || st2->nb_index_entries <= 0)
1522 index = av_index_search_timestamp(
1524 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1525 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));
1528 while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)
1530 ast2->frame_offset = st2->index_entries[index].timestamp;
1534 if (avio_seek(s->pb, pos_min, SEEK_SET) < 0) {
1535 av_log(s, AV_LOG_ERROR, "Seek failed\n");
1538 avi->stream_index= -1;
1539 avi->dts_max= INT_MIN;
1543 static int avi_read_close(AVFormatContext *s)
1546 AVIContext *avi = s->priv_data;
1548 for(i=0;i<s->nb_streams;i++) {
1549 AVStream *st = s->streams[i];
1550 AVIStream *ast = st->priv_data;
1553 av_freep(&ast->sub_ctx->pb);
1554 avformat_close_input(&ast->sub_ctx);
1556 av_free(ast->sub_buffer);
1557 av_free_packet(&ast->sub_pkt);
1561 av_free(avi->dv_demux);
1566 static int avi_probe(AVProbeData *p)
1570 /* check file header */
1571 for(i=0; avi_headers[i][0]; i++)
1572 if(!memcmp(p->buf , avi_headers[i] , 4) &&
1573 !memcmp(p->buf+8, avi_headers[i]+4, 4))
1574 return AVPROBE_SCORE_MAX;
1579 AVInputFormat ff_avi_demuxer = {
1581 .long_name = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),
1582 .priv_data_size = sizeof(AVIContext),
1583 .read_probe = avi_probe,
1584 .read_header = avi_read_header,
1585 .read_packet = avi_read_packet,
1586 .read_close = avi_read_close,
1587 .read_seek = avi_read_seek,
1588 .priv_class = &demuxer_class,