3 * Copyright (c) 2001 Fabrice Bellard.
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.
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.
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
29 typedef struct AVIStream {
30 int64_t frame_offset; /* current frame (video) or byte (audio) counter
31 (used to compute the pts) */
37 int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
39 int64_t cum_len; /* temporary storage (used during seek) */
41 int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
53 DVDemuxContext* dv_demux;
56 static int avi_load_index(AVFormatContext *s);
57 static int guess_ni_flag(AVFormatContext *s);
60 static void print_tag(const char *str, unsigned int tag, int size)
62 printf("%s: tag=%c%c%c%c size=0x%x\n",
71 static int get_riff(AVIContext *avi, ByteIOContext *pb)
74 /* check RIFF header */
77 if (tag != MKTAG('R', 'I', 'F', 'F'))
79 avi->riff_end = get_le32(pb); /* RIFF chunk size */
80 avi->riff_end += url_ftell(pb); /* RIFF chunk end */
82 if (tag != MKTAG('A', 'V', 'I', ' ') && tag != MKTAG('A', 'V', 'I', 'X'))
88 static 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');
101 int64_t last_pos= -1;
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);
106 if(stream_id > s->nb_streams || stream_id < 0)
108 st= s->streams[stream_id];
116 if(index_type && longs_pre_entry != 2)
121 for(i=0; i<entries_in_use; i++){
123 int64_t pos= get_le32(pb) + base - 8;
124 int len = get_le32(pb);
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;
132 av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
135 ast->cum_len += len / ast->sample_size;
140 int64_t offset= get_le64(pb);
141 int size = get_le32(pb);
142 int duration = get_le32(pb);
143 int64_t pos= url_ftell(pb);
145 url_fseek(pb, offset+8, SEEK_SET);
146 read_braindead_odml_indx(s, frame_num);
147 frame_num += duration;
149 url_fseek(pb, pos, SEEK_SET);
155 static void clean_index(AVFormatContext *s){
158 for(i=0; i<s->nb_streams; i++){
159 AVStream *st = s->streams[i];
160 AVIStream *ast = st->priv_data;
161 int n= st->nb_index_entries;
162 int max= ast->sample_size;
163 int64_t pos, size, ts;
165 if(n != 1 || ast->sample_size==0)
168 while(max < 1024) max+=max;
170 pos= st->index_entries[0].pos;
171 size= st->index_entries[0].size;
172 ts= st->index_entries[0].timestamp;
174 for(j=0; j<size; j+=max){
175 av_add_index_entry(st, pos+j, ts + j/ast->sample_size, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
180 static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
182 AVIContext *avi = s->priv_data;
183 ByteIOContext *pb = &s->pb;
184 uint32_t tag, tag1, handler;
185 int codec_type, stream_index, frame_period, bit_rate;
186 unsigned int size, nb_frames;
190 int xan_video = 0; /* hack to support Xan A/V */
192 avi->stream_index= -1;
194 if (get_riff(avi, pb) < 0)
207 print_tag("tag", tag, size);
211 case MKTAG('L', 'I', 'S', 'T'):
212 /* ignored, except when start of video packets */
215 print_tag("list", tag1, 0);
217 if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
218 avi->movi_list = url_ftell(pb) - 4;
219 if(size) avi->movi_end = avi->movi_list + size;
220 else avi->movi_end = url_fsize(pb);
222 printf("movi end=%Lx\n", avi->movi_end);
227 case MKTAG('d', 'm', 'l', 'h'):
229 url_fskip(pb, size + (size & 1));
231 case MKTAG('a', 'v', 'i', 'h'):
233 /* using frame_period is bad idea */
234 frame_period = get_le32(pb);
235 bit_rate = get_le32(pb) * 8;
237 avi->non_interleaved |= get_le32(pb) & AVIF_MUSTUSEINDEX;
239 url_fskip(pb, 2 * 4);
243 st = av_new_stream(s, i);
247 ast = av_mallocz(sizeof(AVIStream));
252 url_fskip(pb, size - 7 * 4);
254 case MKTAG('s', 't', 'r', 'h'):
258 handler = get_le32(pb); /* codec tag */
260 print_tag("strh", tag1, -1);
262 if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
264 * After some consideration -- I don't think we
265 * have to support anything but DV in a type1 AVIs.
267 if (s->nb_streams != 1)
270 if (handler != MKTAG('d', 'v', 's', 'd') &&
271 handler != MKTAG('d', 'v', 'h', 'd') &&
272 handler != MKTAG('d', 'v', 's', 'l'))
275 ast = s->streams[0]->priv_data;
276 av_freep(&s->streams[0]->codec->extradata);
277 av_freep(&s->streams[0]);
279 avi->dv_demux = dv_init_demux(s);
282 s->streams[0]->priv_data = ast;
283 url_fskip(pb, 3 * 4);
284 ast->scale = get_le32(pb);
285 ast->rate = get_le32(pb);
286 stream_index = s->nb_streams - 1;
287 url_fskip(pb, size - 7*4);
291 if (stream_index >= s->nb_streams) {
292 url_fskip(pb, size - 8);
293 /* ignore padding stream */
294 if (tag1 == MKTAG('p', 'a', 'd', 's'))
298 st = s->streams[stream_index];
300 st->codec->stream_codec_tag= handler;
302 get_le32(pb); /* flags */
303 get_le16(pb); /* priority */
304 get_le16(pb); /* language */
305 get_le32(pb); /* initial frame */
306 ast->scale = get_le32(pb);
307 ast->rate = get_le32(pb);
308 if(ast->scale && ast->rate){
309 }else if(frame_period){
311 ast->scale = frame_period;
316 av_set_pts_info(st, 64, ast->scale, ast->rate);
318 ast->cum_len=get_le32(pb); /* start */
319 nb_frames = get_le32(pb);
322 st->duration = nb_frames;
323 get_le32(pb); /* buffer size */
324 get_le32(pb); /* quality */
325 ast->sample_size = get_le32(pb); /* sample ssize */
326 // av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);
329 case MKTAG('v', 'i', 'd', 's'):
330 codec_type = CODEC_TYPE_VIDEO;
332 ast->sample_size = 0;
334 case MKTAG('a', 'u', 'd', 's'):
335 codec_type = CODEC_TYPE_AUDIO;
337 case MKTAG('t', 'x', 't', 's'):
339 codec_type = CODEC_TYPE_DATA; //CODEC_TYPE_SUB ? FIXME
341 case MKTAG('p', 'a', 'd', 's'):
342 codec_type = CODEC_TYPE_UNKNOWN;
346 av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
349 ast->frame_offset= ast->cum_len * FFMAX(ast->sample_size, 1);
350 url_fskip(pb, size - 12 * 4);
352 case MKTAG('s', 't', 'r', 'f'):
354 if (stream_index >= s->nb_streams || avi->dv_demux) {
357 st = s->streams[stream_index];
359 case CODEC_TYPE_VIDEO:
360 get_le32(pb); /* size */
361 st->codec->width = get_le32(pb);
362 st->codec->height = get_le32(pb);
363 get_le16(pb); /* panes */
364 st->codec->bits_per_sample= get_le16(pb); /* depth */
366 get_le32(pb); /* ImageSize */
367 get_le32(pb); /* XPelsPerMeter */
368 get_le32(pb); /* YPelsPerMeter */
369 get_le32(pb); /* ClrUsed */
370 get_le32(pb); /* ClrImportant */
372 if(size > 10*4 && size<(1<<30)){
373 st->codec->extradata_size= size - 10*4;
374 st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
375 get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
378 if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
381 /* Extract palette from extradata if bpp <= 8 */
382 /* This code assumes that extradata contains only palette */
383 /* This is true for all paletted codecs implemented in ffmpeg */
384 if (st->codec->extradata_size && (st->codec->bits_per_sample <= 8)) {
385 st->codec->palctrl = av_mallocz(sizeof(AVPaletteControl));
386 #ifdef WORDS_BIGENDIAN
387 for (i = 0; i < FFMIN(st->codec->extradata_size, AVPALETTE_SIZE)/4; i++)
388 st->codec->palctrl->palette[i] = bswap_32(((uint32_t*)st->codec->extradata)[i]);
390 memcpy(st->codec->palctrl->palette, st->codec->extradata,
391 FFMIN(st->codec->extradata_size, AVPALETTE_SIZE));
393 st->codec->palctrl->palette_changed = 1;
397 print_tag("video", tag1, 0);
399 st->codec->codec_type = CODEC_TYPE_VIDEO;
400 st->codec->codec_tag = tag1;
401 st->codec->codec_id = codec_get_id(codec_bmp_tags, tag1);
402 if (st->codec->codec_id == CODEC_ID_XAN_WC4)
404 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
405 // url_fskip(pb, size - 5 * 4);
407 case CODEC_TYPE_AUDIO:
408 get_wav_header(pb, st->codec, size);
409 if(ast->sample_size && st->codec->block_align && ast->sample_size % st->codec->block_align)
410 av_log(s, AV_LOG_DEBUG, "invalid sample size or block align detected\n");
411 if (size%2) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
413 /* special case time: To support Xan DPCM, hardcode
414 * the format if Xxan is the video codec */
415 st->need_parsing = 1;
416 /* force parsing as several audio frames can be in
419 st->codec->codec_id = CODEC_ID_XAN_DPCM;
422 st->codec->codec_type = CODEC_TYPE_DATA;
423 st->codec->codec_id= CODEC_ID_NONE;
424 st->codec->codec_tag= 0;
430 case MKTAG('i', 'n', 'd', 'x'):
432 read_braindead_odml_indx(s, 0);
434 url_fseek(pb, i+size, SEEK_SET);
444 /* check stream number */
445 if (stream_index != s->nb_streams - 1) {
447 for(i=0;i<s->nb_streams;i++) {
448 av_freep(&s->streams[i]->codec->extradata);
449 av_freep(&s->streams[i]);
454 if(!avi->index_loaded)
456 avi->index_loaded = 1;
457 avi->non_interleaved |= guess_ni_flag(s);
458 if(avi->non_interleaved)
464 static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
466 AVIContext *avi = s->priv_data;
467 ByteIOContext *pb = &s->pb;
473 size = dv_get_packet(avi->dv_demux, pkt);
478 if(avi->non_interleaved){
479 int best_stream_index = 0;
480 AVStream *best_st= NULL;
482 int64_t best_ts= INT64_MAX;
485 for(i=0; i<s->nb_streams; i++){
486 AVStream *st = s->streams[i];
487 AVIStream *ast = st->priv_data;
488 int64_t ts= ast->frame_offset;
491 ts /= ast->sample_size;
492 ts= av_rescale(ts, AV_TIME_BASE * (int64_t)st->time_base.num, st->time_base.den);
494 // av_log(NULL, AV_LOG_DEBUG, "%Ld %d/%d %Ld\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);
498 best_stream_index= i;
501 best_ast = best_st->priv_data;
502 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
503 if(best_ast->remaining)
504 i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
506 i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
508 // av_log(NULL, AV_LOG_DEBUG, "%d\n", i);
510 int64_t pos= best_st->index_entries[i].pos;
511 pos += best_ast->packet_size - best_ast->remaining;
512 url_fseek(&s->pb, pos + 8, SEEK_SET);
513 // av_log(NULL, AV_LOG_DEBUG, "pos=%Ld\n", pos);
515 assert(best_ast->remaining <= best_ast->packet_size);
517 avi->stream_index= best_stream_index;
518 if(!best_ast->remaining)
519 best_ast->packet_size=
520 best_ast->remaining= best_st->index_entries[i].size;
525 if(avi->stream_index >= 0){
526 AVStream *st= s->streams[ avi->stream_index ];
527 AVIStream *ast= st->priv_data;
530 if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
532 else if(ast->sample_size < 32)
533 size= 64*ast->sample_size;
535 size= ast->sample_size;
537 if(size > ast->remaining)
538 size= ast->remaining;
539 av_get_packet(pb, pkt, size);
542 dstr = pkt->destruct;
543 size = dv_produce_packet(avi->dv_demux, pkt,
544 pkt->data, pkt->size);
545 pkt->destruct = dstr;
546 pkt->flags |= PKT_FLAG_KEY;
548 /* XXX: how to handle B frames in avi ? */
549 pkt->dts = ast->frame_offset;
550 // pkt->dts += ast->start;
552 pkt->dts /= ast->sample_size;
553 //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);
554 pkt->stream_index = avi->stream_index;
556 if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
557 if(st->index_entries){
561 index= av_index_search_timestamp(st, pkt->dts, 0);
562 e= &st->index_entries[index];
564 if(index >= 0 && e->timestamp == ast->frame_offset){
565 if (e->flags & AVINDEX_KEYFRAME)
566 pkt->flags |= PKT_FLAG_KEY;
569 /* if no index, better to say that all frames
571 pkt->flags |= PKT_FLAG_KEY;
574 pkt->flags |= PKT_FLAG_KEY;
577 ast->frame_offset += pkt->size;
581 ast->remaining -= size;
583 avi->stream_index= -1;
594 memset(d, -1, sizeof(int)*8);
595 for(i=sync=url_ftell(pb); !url_feof(pb); i++) {
598 if (i >= avi->movi_end) {
600 url_fskip(pb, avi->riff_end - i);
601 avi->riff_end = avi->movi_end = url_fsize(pb);
610 size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
612 if( d[2] >= '0' && d[2] <= '9'
613 && d[3] >= '0' && d[3] <= '9'){
614 n= (d[2] - '0') * 10 + (d[3] - '0');
616 n= 100; //invalid stream id
618 //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);
619 if(i + size > avi->movi_end || d[0]<0)
623 if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
625 ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')){
627 //av_log(NULL, AV_LOG_DEBUG, "SKIP\n");
631 if( d[0] >= '0' && d[0] <= '9'
632 && d[1] >= '0' && d[1] <= '9'){
633 n= (d[0] - '0') * 10 + (d[1] - '0');
635 n= 100; //invalid stream id
639 if(n < s->nb_streams){
645 if( (st->discard >= AVDISCARD_DEFAULT && size==0)
646 /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & PKT_FLAG_KEY))*/ //FIXME needs a little reordering
647 || st->discard >= AVDISCARD_ALL){
648 if(ast->sample_size) ast->frame_offset += pkt->size;
649 else ast->frame_offset++;
654 if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
655 d[2]*256+d[3] == ast->prefix /*||
656 (d[2] == 'd' && d[3] == 'c') ||
657 (d[2] == 'w' && d[3] == 'b')*/) {
659 //av_log(NULL, AV_LOG_DEBUG, "OK\n");
660 if(d[2]*256+d[3] == ast->prefix)
663 ast->prefix= d[2]*256+d[3];
664 ast->prefix_count= 0;
667 avi->stream_index= n;
668 ast->packet_size= size + 8;
669 ast->remaining= size;
673 /* palette changed chunk */
674 if ( d[0] >= '0' && d[0] <= '9'
675 && d[1] >= '0' && d[1] <= '9'
676 && ((d[2] == 'p' && d[3] == 'c'))
677 && n < s->nb_streams && i + size <= avi->movi_end) {
680 int first, clr, flags, k, p;
684 first = get_byte(pb);
686 if(!clr) /* all 256 colors used */
688 flags = get_le16(pb);
690 for (k = first; k < clr + first; k++) {
696 st->codec->palctrl->palette[k] = b + (g << 8) + (r << 16);
698 st->codec->palctrl->palette_changed = 1;
707 /* XXX: we make the implicit supposition that the position are sorted
709 static int avi_read_idx1(AVFormatContext *s, int size)
711 AVIContext *avi = s->priv_data;
712 ByteIOContext *pb = &s->pb;
713 int nb_index_entries, i;
716 unsigned int index, tag, flags, pos, len;
717 unsigned last_pos= -1;
719 nb_index_entries = size / 16;
720 if (nb_index_entries <= 0)
723 /* read the entries and sort them in each stream component */
724 for(i = 0; i < nb_index_entries; i++) {
726 flags = get_le32(pb);
729 #if defined(DEBUG_SEEK)
730 av_log(NULL, AV_LOG_DEBUG, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
731 i, tag, flags, pos, len);
733 if(i==0 && pos > avi->movi_list)
734 avi->movi_list= 0; //FIXME better check
735 pos += avi->movi_list;
737 index = ((tag & 0xff) - '0') * 10;
738 index += ((tag >> 8) & 0xff) - '0';
739 if (index >= s->nb_streams)
741 st = s->streams[index];
744 #if defined(DEBUG_SEEK)
745 av_log(NULL, AV_LOG_DEBUG, "%d cum_len=%d\n", len, ast->cum_len);
748 avi->non_interleaved= 1;
750 av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
752 ast->cum_len += len / ast->sample_size;
760 static int guess_ni_flag(AVFormatContext *s){
762 int64_t last_start=0;
763 int64_t first_end= INT64_MAX;
765 for(i=0; i<s->nb_streams; i++){
766 AVStream *st = s->streams[i];
767 int n= st->nb_index_entries;
772 if(st->index_entries[0].pos > last_start)
773 last_start= st->index_entries[0].pos;
774 if(st->index_entries[n-1].pos < first_end)
775 first_end= st->index_entries[n-1].pos;
777 return last_start > first_end;
780 static int avi_load_index(AVFormatContext *s)
782 AVIContext *avi = s->priv_data;
783 ByteIOContext *pb = &s->pb;
785 offset_t pos= url_ftell(pb);
787 url_fseek(pb, avi->movi_end, SEEK_SET);
789 printf("movi_end=0x%llx\n", avi->movi_end);
797 printf("tag=%c%c%c%c size=0x%x\n",
805 case MKTAG('i', 'd', 'x', '1'):
806 if (avi_read_idx1(s, size) < 0)
819 url_fseek(pb, pos, SEEK_SET);
823 static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
825 AVIContext *avi = s->priv_data;
830 if (!avi->index_loaded) {
831 /* we only load the index on demand */
833 avi->index_loaded = 1;
835 assert(stream_index>= 0);
837 st = s->streams[stream_index];
838 index= av_index_search_timestamp(st, timestamp, flags);
842 /* find the position */
843 pos = st->index_entries[index].pos;
844 timestamp = st->index_entries[index].timestamp;
846 // av_log(NULL, AV_LOG_DEBUG, "XX %Ld %d %Ld\n", timestamp, index, st->index_entries[index].timestamp);
848 for(i = 0; i < s->nb_streams; i++) {
849 AVStream *st2 = s->streams[i];
850 AVIStream *ast2 = st2->priv_data;
855 if (st2->nb_index_entries <= 0)
858 // assert(st2->codec->block_align);
859 assert(st2->time_base.den == ast2->rate);
860 assert(st2->time_base.num == ast2->scale);
861 index = av_index_search_timestamp(
863 av_rescale(timestamp, st2->time_base.den*(int64_t)st->time_base.num, st->time_base.den * (int64_t)st2->time_base.num),
864 flags | AVSEEK_FLAG_BACKWARD);
868 if(!avi->non_interleaved){
869 while(index>0 && st2->index_entries[index].pos > pos)
871 while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
875 // av_log(NULL, AV_LOG_DEBUG, "%Ld %d %Ld\n", timestamp, index, st2->index_entries[index].timestamp);
876 /* extract the current frame number */
877 ast2->frame_offset = st2->index_entries[index].timestamp;
878 if(ast2->sample_size)
879 ast2->frame_offset *=ast2->sample_size;
883 dv_flush_audio_packets(avi->dv_demux);
885 url_fseek(&s->pb, pos, SEEK_SET);
886 avi->stream_index= -1;
890 static int avi_read_close(AVFormatContext *s)
893 AVIContext *avi = s->priv_data;
895 for(i=0;i<s->nb_streams;i++) {
896 AVStream *st = s->streams[i];
897 AVIStream *ast = st->priv_data;
899 av_free(st->codec->extradata);
900 av_free(st->codec->palctrl);
904 av_free(avi->dv_demux);
909 static int avi_probe(AVProbeData *p)
911 /* check file header */
912 if (p->buf_size <= 32)
914 if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
915 p->buf[2] == 'F' && p->buf[3] == 'F' &&
916 p->buf[8] == 'A' && p->buf[9] == 'V' &&
917 p->buf[10] == 'I' && p->buf[11] == ' ')
918 return AVPROBE_SCORE_MAX;
923 static AVInputFormat avi_iformat = {
934 int avidec_init(void)
936 av_register_input_format(&avi_iformat);