/*
* AVI demuxer
* Copyright (c) 2001 Fabrice Bellard
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "libavutil/mathematics.h"
#include "libavutil/bswap.h"
#include "libavutil/opt.h"
#include "libavutil/dict.h"
#include "libavutil/avstring.h"
#include "avformat.h"
#include "internal.h"
#include "avi.h"
#include "dv.h"
#include "riff.h"
#undef NDEBUG
#include <assert.h>
typedef struct AVIStream {
int64_t frame_offset; /* current frame (video) or byte (audio) counter
(used to compute the pts) */
int remaining;
int packet_size;
int scale;
int rate;
int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
int64_t cum_len; /* temporary storage (used during seek) */
int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
int prefix_count;
uint32_t pal[256];
int has_pal;
int dshow_block_align; ///< block align variable used to emulate bugs in the MS dshow demuxer
AVFormatContext *sub_ctx;
AVPacket sub_pkt;
uint8_t *sub_buffer;
int64_t seek_pos;
} AVIStream;
typedef struct {
const AVClass *class;
int64_t riff_end;
int64_t movi_end;
int64_t fsize;
int64_t movi_list;
int64_t last_pkt_pos;
int index_loaded;
int is_odml;
int non_interleaved;
int stream_index;
DVDemuxContext* dv_demux;
int odml_depth;
int use_odml;
#define MAX_ODML_DEPTH 1000
int64_t dts_max;
} AVIContext;
static const AVOption options[] = {
{ "use_odml", "use odml index", offsetof(AVIContext, use_odml), AV_OPT_TYPE_INT, {.dbl = 1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM},
{ NULL },
};
static const AVClass demuxer_class = {
"AVI demuxer",
av_default_item_name,
options,
LIBAVUTIL_VERSION_INT,
};
static const char avi_headers[][8] = {
{ 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' ' },
{ 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X' },
{ 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19},
{ 'O', 'N', '2', ' ', 'O', 'N', '2', 'f' },
{ 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' ' },
{ 0 }
};
static const AVMetadataConv avi_metadata_conv[] = {
{ "strn", "title" },
{ 0 },
};
static int avi_load_index(AVFormatContext *s);
static int guess_ni_flag(AVFormatContext *s);
#define print_tag(str, tag, size) \
av_dlog(NULL, "%s: tag=%c%c%c%c size=0x%x\n", \
str, tag & 0xff, \
(tag >> 8) & 0xff, \
(tag >> 16) & 0xff, \
(tag >> 24) & 0xff, \
size)
static inline int get_duration(AVIStream *ast, int len){
if(ast->sample_size){
return len;
}else if (ast->dshow_block_align){
return (len + ast->dshow_block_align - 1)/ast->dshow_block_align;
}else
return 1;
}
static int get_riff(AVFormatContext *s, AVIOContext *pb)
{
AVIContext *avi = s->priv_data;
char header[8];
int i;
/* check RIFF header */
avio_read(pb, header, 4);
avi->riff_end = avio_rl32(pb); /* RIFF chunk size */
avi->riff_end += avio_tell(pb); /* RIFF chunk end */
avio_read(pb, header+4, 4);
for(i=0; avi_headers[i][0]; i++)
if(!memcmp(header, avi_headers[i], 8))
break;
if(!avi_headers[i][0])
return -1;
if(header[7] == 0x19)
av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");
return 0;
}
static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int longs_pre_entry= avio_rl16(pb);
int index_sub_type = avio_r8(pb);
int index_type = avio_r8(pb);
int entries_in_use = avio_rl32(pb);
int chunk_id = avio_rl32(pb);
int64_t base = avio_rl64(pb);
int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
AVStream *st;
AVIStream *ast;
int i;
int64_t last_pos= -1;
int64_t filesize= avi->fsize;
av_dlog(s, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",
longs_pre_entry,index_type, entries_in_use, chunk_id, base);
if(stream_id >= s->nb_streams || stream_id < 0)
return -1;
st= s->streams[stream_id];
ast = st->priv_data;
if(index_sub_type)
return -1;
avio_rl32(pb);
if(index_type && longs_pre_entry != 2)
return -1;
if(index_type>1)
return -1;
if(filesize > 0 && base >= filesize){
av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)
base &= 0xFFFFFFFF;
else
return -1;
}
for(i=0; i<entries_in_use; i++){
if(index_type){
int64_t pos= avio_rl32(pb) + base - 8;
int len = avio_rl32(pb);
int key= len >= 0;
len &= 0x7FFFFFFF;
#ifdef DEBUG_SEEK
av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);
#endif
if(url_feof(pb))
return -1;
if(last_pos == pos || pos == base - 8)
avi->non_interleaved= 1;
if(last_pos != pos && (len || !ast->sample_size))
av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
ast->cum_len += get_duration(ast, len);
last_pos= pos;
}else{
int64_t offset, pos;
int duration;
offset = avio_rl64(pb);
avio_rl32(pb); /* size */
duration = avio_rl32(pb);
if(url_feof(pb))
return -1;
pos = avio_tell(pb);
if(avi->odml_depth > MAX_ODML_DEPTH){
av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");
return -1;
}
if(avio_seek(pb, offset+8, SEEK_SET) < 0)
return -1;
avi->odml_depth++;
read_braindead_odml_indx(s, frame_num);
avi->odml_depth--;
frame_num += duration;
if(avio_seek(pb, pos, SEEK_SET) < 0) {
av_log(s, AV_LOG_ERROR, "Failed to restore position after reading index");
return -1;
}
}
}
avi->index_loaded=2;
return 0;
}
static void clean_index(AVFormatContext *s){
int i;
int64_t j;
for(i=0; i<s->nb_streams; i++){
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
int n= st->nb_index_entries;
int max= ast->sample_size;
int64_t pos, size, ts;
if(n != 1 || ast->sample_size==0)
continue;
while(max < 1024) max+=max;
pos= st->index_entries[0].pos;
size= st->index_entries[0].size;
ts= st->index_entries[0].timestamp;
for(j=0; j<size; j+=max){
av_add_index_entry(st, pos+j, ts+j, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
}
}
}
static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag, uint32_t size)
{
AVIOContext *pb = s->pb;
char key[5] = {0}, *value;
size += (size & 1);
if (size == UINT_MAX)
return -1;
value = av_malloc(size+1);
if (!value)
return -1;
avio_read(pb, value, size);
value[size]=0;
AV_WL32(key, tag);
return av_dict_set(st ? &st->metadata : &s->metadata, key, value,
AV_DICT_DONT_STRDUP_VAL);
}
static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
static void avi_metadata_creation_time(AVDictionary **metadata, char *date)
{
char month[4], time[9], buffer[64];
int i, day, year;
/* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */
if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",
month, &day, time, &year) == 4) {
for (i=0; i<12; i++)
if (!av_strcasecmp(month, months[i])) {
snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",
year, i+1, day, time);
av_dict_set(metadata, "creation_time", buffer, 0);
}
} else if (date[4] == '/' && date[7] == '/') {
date[4] = date[7] = '-';
av_dict_set(metadata, "creation_time", date, 0);
}
}
static void avi_read_nikon(AVFormatContext *s, uint64_t end)
{
while (avio_tell(s->pb) < end) {
uint32_t tag = avio_rl32(s->pb);
uint32_t size = avio_rl32(s->pb);
switch (tag) {
case MKTAG('n', 'c', 't', 'g'): { /* Nikon Tags */
uint64_t tag_end = avio_tell(s->pb) + size;
while (avio_tell(s->pb) < tag_end) {
uint16_t tag = avio_rl16(s->pb);
uint16_t size = avio_rl16(s->pb);
const char *name = NULL;
char buffer[64] = {0};
size -= avio_read(s->pb, buffer,
FFMIN(size, sizeof(buffer)-1));
switch (tag) {
case 0x03: name = "maker"; break;
case 0x04: name = "model"; break;
case 0x13: name = "creation_time";
if (buffer[4] == ':' && buffer[7] == ':')
buffer[4] = buffer[7] = '-';
break;
}
if (name)
av_dict_set(&s->metadata, name, buffer, 0);
avio_skip(s->pb, size);
}
break;
}
default:
avio_skip(s->pb, size);
break;
}
}
}
static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
unsigned int tag, tag1, handler;
int codec_type, stream_index, frame_period;
unsigned int size;
int i;
AVStream *st;
AVIStream *ast = NULL;
int avih_width=0, avih_height=0;
int amv_file_format=0;
uint64_t list_end = 0;
int ret;
avi->stream_index= -1;
if (get_riff(s, pb) < 0)
return -1;
av_log(avi, AV_LOG_DEBUG, "use odml:%d\n", avi->use_odml);
avi->fsize = avio_size(pb);
if(avi->fsize<=0 || avi->fsize < avi->riff_end)
avi->fsize= avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
/* first list tag */
stream_index = -1;
codec_type = -1;
frame_period = 0;
for(;;) {
if (url_feof(pb))
goto fail;
tag = avio_rl32(pb);
size = avio_rl32(pb);
if(size > avi->fsize){
av_log(s, AV_LOG_ERROR, "chunk size is too big during header parsing\n");
goto fail;
}
print_tag("tag", tag, size);
switch(tag) {
case MKTAG('L', 'I', 'S', 'T'):
list_end = avio_tell(pb) + size;
/* Ignored, except at start of video packets. */
tag1 = avio_rl32(pb);
print_tag("list", tag1, 0);
if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
avi->movi_list = avio_tell(pb) - 4;
if(size) avi->movi_end = avi->movi_list + size + (size & 1);
else avi->movi_end = avi->fsize;
av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);
goto end_of_header;
}
else if (tag1 == MKTAG('I', 'N', 'F', 'O'))
ff_read_riff_info(s, size - 4);
else if (tag1 == MKTAG('n', 'c', 'd', 't'))
avi_read_nikon(s, list_end);
break;
case MKTAG('I', 'D', 'I', 'T'): {
unsigned char date[64] = {0};
size += (size & 1);
size -= avio_read(pb, date, FFMIN(size, sizeof(date)-1));
avio_skip(pb, size);
avi_metadata_creation_time(&s->metadata, date);
break;
}
case MKTAG('d', 'm', 'l', 'h'):
avi->is_odml = 1;
avio_skip(pb, size + (size & 1));
break;
case MKTAG('a', 'm', 'v', 'h'):
amv_file_format=1;
case MKTAG('a', 'v', 'i', 'h'):
/* AVI header */
/* using frame_period is bad idea */
frame_period = avio_rl32(pb);
avio_rl32(pb); /* max. bytes per second */
avio_rl32(pb);
avi->non_interleaved |= avio_rl32(pb) & AVIF_MUSTUSEINDEX;
avio_skip(pb, 2 * 4);
avio_rl32(pb);
avio_rl32(pb);
avih_width=avio_rl32(pb);
avih_height=avio_rl32(pb);
avio_skip(pb, size - 10 * 4);
break;
case MKTAG('s', 't', 'r', 'h'):
/* stream header */
tag1 = avio_rl32(pb);
handler = avio_rl32(pb); /* codec tag */
if(tag1 == MKTAG('p', 'a', 'd', 's')){
avio_skip(pb, size - 8);
break;
}else{
stream_index++;
st = avformat_new_stream(s, NULL);
if (!st)
goto fail;
st->id = stream_index;
ast = av_mallocz(sizeof(AVIStream));
if (!ast)
goto fail;
st->priv_data = ast;
}
if(amv_file_format)
tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');
print_tag("strh", tag1, -1);
if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
int64_t dv_dur;
/*
* After some consideration -- I don't think we
* have to support anything but DV in type1 AVIs.
*/
if (s->nb_streams != 1)
goto fail;
if (handler != MKTAG('d', 'v', 's', 'd') &&
handler != MKTAG('d', 'v', 'h', 'd') &&
handler != MKTAG('d', 'v', 's', 'l'))
goto fail;
ast = s->streams[0]->priv_data;
av_freep(&s->streams[0]->codec->extradata);
av_freep(&s->streams[0]->codec);
av_freep(&s->streams[0]);
s->nb_streams = 0;
if (CONFIG_DV_DEMUXER) {
avi->dv_demux = avpriv_dv_init_demux(s);
if (!avi->dv_demux)
goto fail;
}
s->streams[0]->priv_data = ast;
avio_skip(pb, 3 * 4);
ast->scale = avio_rl32(pb);
ast->rate = avio_rl32(pb);
avio_skip(pb, 4); /* start time */
dv_dur = avio_rl32(pb);
if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
dv_dur *= AV_TIME_BASE;
s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
}
/*
* else, leave duration alone; timing estimation in utils.c
* will make a guess based on bitrate.
*/
stream_index = s->nb_streams - 1;
avio_skip(pb, size - 9*4);
break;
}
assert(stream_index < s->nb_streams);
st->codec->stream_codec_tag= handler;
avio_rl32(pb); /* flags */
avio_rl16(pb); /* priority */
avio_rl16(pb); /* language */
avio_rl32(pb); /* initial frame */
ast->scale = avio_rl32(pb);
ast->rate = avio_rl32(pb);
if(!(ast->scale && ast->rate)){
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);
if(frame_period){
ast->rate = 1000000;
ast->scale = frame_period;
}else{
ast->rate = 25;
ast->scale = 1;
}
}
avpriv_set_pts_info(st, 64, ast->scale, ast->rate);
ast->cum_len=avio_rl32(pb); /* start */
st->nb_frames = avio_rl32(pb);
st->start_time = 0;
avio_rl32(pb); /* buffer size */
avio_rl32(pb); /* quality */
ast->sample_size = avio_rl32(pb); /* sample ssize */
ast->cum_len *= FFMAX(1, ast->sample_size);
// av_log(s, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);
switch(tag1) {
case MKTAG('v', 'i', 'd', 's'):
codec_type = AVMEDIA_TYPE_VIDEO;
ast->sample_size = 0;
break;
case MKTAG('a', 'u', 'd', 's'):
codec_type = AVMEDIA_TYPE_AUDIO;
break;
case MKTAG('t', 'x', 't', 's'):
codec_type = AVMEDIA_TYPE_SUBTITLE;
break;
case MKTAG('d', 'a', 't', 's'):
codec_type = AVMEDIA_TYPE_DATA;
break;
default:
av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);
}
if(ast->sample_size == 0)
st->duration = st->nb_frames;
ast->frame_offset= ast->cum_len;
avio_skip(pb, size - 12 * 4);
break;
case MKTAG('s', 't', 'r', 'f'):
/* stream header */
if (!size)
break;
if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
avio_skip(pb, size);
} else {
uint64_t cur_pos = avio_tell(pb);
if (cur_pos < list_end)
size = FFMIN(size, list_end - cur_pos);
st = s->streams[stream_index];
switch(codec_type) {
case AVMEDIA_TYPE_VIDEO:
if(amv_file_format){
st->codec->width=avih_width;
st->codec->height=avih_height;
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_AMV;
avio_skip(pb, size);
break;
}
tag1 = ff_get_bmp_header(pb, st);
if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {
st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->codec->codec_tag = tag1;
st->codec->codec_id = CODEC_ID_XSUB;
break;
}
if(size > 10*4 && size<(1<<30)){
st->codec->extradata_size= size - 10*4;
st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata) {
st->codec->extradata_size= 0;
return AVERROR(ENOMEM);
}
avio_read(pb, st->codec->extradata, st->codec->extradata_size);
}
if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
avio_r8(pb);
/* Extract palette from extradata if bpp <= 8. */
/* This code assumes that extradata contains only palette. */
/* This is true for all paletted codecs implemented in FFmpeg. */
if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {
int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
const uint8_t *pal_src;
pal_size = FFMIN(pal_size, st->codec->extradata_size);
pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;
#if HAVE_BIGENDIAN
for (i = 0; i < pal_size/4; i++)
ast->pal[i] = AV_RL32(pal_src+4*i);
#else
memcpy(ast->pal, pal_src, pal_size);
#endif
ast->has_pal = 1;
}
print_tag("video", tag1, 0);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_tag = tag1;
st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tag1);
st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.
// Support "Resolution 1:1" for Avid AVI Codec
if(tag1 == MKTAG('A', 'V', 'R', 'n') &&
st->codec->extradata_size >= 31 &&
!memcmp(&st->codec->extradata[28], "1:1", 3))
st->codec->codec_id = CODEC_ID_RAWVIDEO;
if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){
st->codec->extradata_size+= 9;
st->codec->extradata= av_realloc_f(st->codec->extradata, 1, st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
if(st->codec->extradata)
memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);
}
st->codec->height= FFABS(st->codec->height);
// avio_skip(pb, size - 5 * 4);
break;
case AVMEDIA_TYPE_AUDIO:
ret = ff_get_wav_header(pb, st->codec, size);
if (ret < 0)
return ret;
ast->dshow_block_align= st->codec->block_align;
if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){
av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);
ast->sample_size= st->codec->block_align;
}
if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
avio_skip(pb, 1);
/* Force parsing as several audio frames can be in
* one packet and timestamps refer to packet start. */
st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;
/* ADTS header is in extradata, AAC without header must be
* stored as exact frames. Parser not needed and it will
* fail. */
if (st->codec->codec_id == CODEC_ID_AAC && st->codec->extradata_size)
st->need_parsing = AVSTREAM_PARSE_NONE;
/* AVI files with Xan DPCM audio (wrongly) declare PCM
* audio in the header but have Axan as stream_code_tag. */
if (st->codec->stream_codec_tag == AV_RL32("Axan")){
st->codec->codec_id = CODEC_ID_XAN_DPCM;
st->codec->codec_tag = 0;
ast->dshow_block_align = 0;
}
if (amv_file_format){
st->codec->codec_id = CODEC_ID_ADPCM_IMA_AMV;
ast->dshow_block_align = 0;
}
break;
case AVMEDIA_TYPE_SUBTITLE:
st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->request_probe= 1;
break;
default:
st->codec->codec_type = AVMEDIA_TYPE_DATA;
st->codec->codec_id= CODEC_ID_NONE;
st->codec->codec_tag= 0;
avio_skip(pb, size);
break;
}
}
break;
case MKTAG('i', 'n', 'd', 'x'):
i= avio_tell(pb);
if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) && avi->use_odml &&
read_braindead_odml_indx(s, 0) < 0 && s->error_recognition >= FF_ER_EXPLODE){
goto fail; }
avio_seek(pb, i+size, SEEK_SET);
break;
case MKTAG('v', 'p', 'r', 'p'):
if(stream_index < (unsigned)s->nb_streams && size > 9*4){
AVRational active, active_aspect;
st = s->streams[stream_index];
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
active_aspect.den= avio_rl16(pb);
active_aspect.num= avio_rl16(pb);
active.num = avio_rl32(pb);
active.den = avio_rl32(pb);
avio_rl32(pb); //nbFieldsPerFrame
if(active_aspect.num && active_aspect.den && active.num && active.den){
st->sample_aspect_ratio= av_div_q(active_aspect, active);
//av_log(s, AV_LOG_ERROR, "vprp %d/%d %d/%d\n", active_aspect.num, active_aspect.den, active.num, active.den);
}
size -= 9*4;
}
avio_skip(pb, size);
break;
case MKTAG('s', 't', 'r', 'n'):
if(s->nb_streams){
avi_read_tag(s, s->streams[s->nb_streams-1], tag, size);
break;
}
default:
if(size > 1000000){
av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "
"I will ignore it and try to continue anyway.\n");
if (s->error_recognition >= FF_ER_EXPLODE) goto fail;
avi->movi_list = avio_tell(pb) - 4;
avi->movi_end = avi->fsize;
goto end_of_header;
}
/* skip tag */
size += (size & 1);
avio_skip(pb, size);
break;
}
}
end_of_header:
/* check stream number */
if (stream_index != s->nb_streams - 1) {
fail:
return -1;
}
if(!avi->index_loaded && pb->seekable)
avi_load_index(s);
avi->index_loaded |= 1;
avi->non_interleaved |= guess_ni_flag(s) | (s->flags & AVFMT_FLAG_SORT_DTS);
for(i=0; i<s->nb_streams; i++){
AVStream *st = s->streams[i];
if(st->nb_index_entries)
break;
}
// DV-in-AVI cannot be non-interleaved, if set this must be
// a mis-detection.
if(avi->dv_demux)
avi->non_interleaved=0;
if(i==s->nb_streams && avi->non_interleaved) {
av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");
avi->non_interleaved=0;
}
if(avi->non_interleaved) {
av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
clean_index(s);
}
ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);
return 0;
}
static int read_gab2_sub(AVStream *st, AVPacket *pkt) {
if (!strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data+5) == 2) {
uint8_t desc[256];
int score = AVPROBE_SCORE_MAX / 2, ret;
AVIStream *ast = st->priv_data;
AVInputFormat *sub_demuxer;
AVRational time_base;
AVIOContext *pb = avio_alloc_context( pkt->data + 7,
pkt->size - 7,
0, NULL, NULL, NULL, NULL);
AVProbeData pd;
unsigned int desc_len = avio_rl32(pb);
if (desc_len > pb->buf_end - pb->buf_ptr)
goto error;
ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
avio_skip(pb, desc_len - ret);
if (*desc)
av_dict_set(&st->metadata, "title", desc, 0);
avio_rl16(pb); /* flags? */
avio_rl32(pb); /* data size */
pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };
if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))
goto error;
if (!(ast->sub_ctx = avformat_alloc_context()))
goto error;
ast->sub_ctx->pb = pb;
if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
av_read_packet(ast->sub_ctx, &ast->sub_pkt);
*st->codec = *ast->sub_ctx->streams[0]->codec;
ast->sub_ctx->streams[0]->codec->extradata = NULL;
time_base = ast->sub_ctx->streams[0]->time_base;
avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
}
ast->sub_buffer = pkt->data;
memset(pkt, 0, sizeof(*pkt));
return 1;
error:
av_freep(&pb);
}
return 0;
}
static AVStream *get_subtitle_pkt(AVFormatContext *s, AVStream *next_st,
AVPacket *pkt)
{
AVIStream *ast, *next_ast = next_st->priv_data;
int64_t ts, next_ts, ts_min = INT64_MAX;
AVStream *st, *sub_st = NULL;
int i;
next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
AV_TIME_BASE_Q);
for (i=0; i<s->nb_streams; i++) {
st = s->streams[i];
ast = st->priv_data;
if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
ts = av_rescale_q(ast->sub_pkt.dts, st->time_base, AV_TIME_BASE_Q);
if (ts <= next_ts && ts < ts_min) {
ts_min = ts;
sub_st = st;
}
}
}
if (sub_st) {
ast = sub_st->priv_data;
*pkt = ast->sub_pkt;
pkt->stream_index = sub_st->index;
if (av_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
ast->sub_pkt.data = NULL;
}
return sub_st;
}
static int get_stream_idx(int *d){
if( d[0] >= '0' && d[0] <= '9'
&& d[1] >= '0' && d[1] <= '9'){
return (d[0] - '0') * 10 + (d[1] - '0');
}else{
return 100; //invalid stream ID
}
}
static int avi_sync(AVFormatContext *s, int exit_early)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int n;
unsigned int d[8];
unsigned int size;
int64_t i, sync;
start_sync:
memset(d, -1, sizeof(d));
for(i=sync=avio_tell(pb); !url_feof(pb); i++) {
int j;
for(j=0; j<7; j++)
d[j]= d[j+1];
d[7]= avio_r8(pb);
size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
n= get_stream_idx(d+2);
//av_log(s, AV_LOG_DEBUG, "%X %X %X %X %X %X %X %X %"PRId64" %d %d\n", d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
if(i + (uint64_t)size > avi->fsize || d[0] > 127)
continue;
//parse ix##
if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
//parse JUNK
||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')
||(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')){
avio_skip(pb, size);
//av_log(s, AV_LOG_DEBUG, "SKIP\n");
goto start_sync;
}
//parse stray LIST
if(d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T'){
avio_skip(pb, 4);
goto start_sync;
}
n= get_stream_idx(d);
if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)
continue;
//detect ##ix chunk and skip
if(d[2] == 'i' && d[3] == 'x' && n < s->nb_streams){
avio_skip(pb, size);
goto start_sync;
}
//parse ##dc/##wb
if(n < s->nb_streams){
AVStream *st;
AVIStream *ast;
st = s->streams[n];
ast = st->priv_data;
if(s->nb_streams>=2){
AVStream *st1 = s->streams[1];
AVIStream *ast1= st1->priv_data;
//workaround for broken small-file-bug402.avi
if( d[2] == 'w' && d[3] == 'b'
&& n==0
&& st ->codec->codec_type == AVMEDIA_TYPE_VIDEO
&& st1->codec->codec_type == AVMEDIA_TYPE_AUDIO
&& ast->prefix == 'd'*256+'c'
&& (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
){
n=1;
st = st1;
ast = ast1;
av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");
}
}
if( (st->discard >= AVDISCARD_DEFAULT && size==0)
/*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & AV_PKT_FLAG_KEY))*/ //FIXME needs a little reordering
|| st->discard >= AVDISCARD_ALL){
if (!exit_early) {
ast->frame_offset += get_duration(ast, size);
}
avio_skip(pb, size);
goto start_sync;
}
if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {
int k = avio_r8(pb);
int last = (k + avio_r8(pb) - 1) & 0xFF;
avio_rl16(pb); //flags
for (; k <= last; k++)
ast->pal[k] = avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);
ast->has_pal= 1;
goto start_sync;
} else if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
d[2]*256+d[3] == ast->prefix /*||
(d[2] == 'd' && d[3] == 'c') ||
(d[2] == 'w' && d[3] == 'b')*/) {
if (exit_early)
return 0;
//av_log(s, AV_LOG_DEBUG, "OK\n");
if(d[2]*256+d[3] == ast->prefix)
ast->prefix_count++;
else{
ast->prefix= d[2]*256+d[3];
ast->prefix_count= 0;
}
avi->stream_index= n;
ast->packet_size= size + 8;
ast->remaining= size;
if(size || !ast->sample_size){
uint64_t pos= avio_tell(pb) - 8;
if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){
av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);
}
}
return 0;
}
}
}
if(pb->error)
return pb->error;
return AVERROR_EOF;
}
static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int err;
void* dstr;
if (CONFIG_DV_DEMUXER && avi->dv_demux) {
int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
if (size >= 0)
return size;
}
if(avi->non_interleaved){
int best_stream_index = 0;
AVStream *best_st= NULL;
AVIStream *best_ast;
int64_t best_ts= INT64_MAX;
int i;
for(i=0; i<s->nb_streams; i++){
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
int64_t ts= ast->frame_offset;
int64_t last_ts;
if(!st->nb_index_entries)
continue;
last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
if(!ast->remaining && ts > last_ts)
continue;
ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});
// av_log(s, AV_LOG_DEBUG, "%"PRId64" %d/%d %"PRId64"\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);
if(ts < best_ts){
best_ts= ts;
best_st= st;
best_stream_index= i;
}
}
if(!best_st)
return AVERROR_EOF;
best_ast = best_st->priv_data;
best_ts = best_ast->frame_offset;
if(best_ast->remaining)
i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
else{
i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
if(i>=0)
best_ast->frame_offset= best_st->index_entries[i].timestamp;
}
// av_log(s, AV_LOG_DEBUG, "%d\n", i);
if(i>=0){
int64_t pos= best_st->index_entries[i].pos;
pos += best_ast->packet_size - best_ast->remaining;
if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)
return AVERROR_EOF;
// av_log(s, AV_LOG_DEBUG, "pos=%"PRId64"\n", pos);
assert(best_ast->remaining <= best_ast->packet_size);
avi->stream_index= best_stream_index;
if(!best_ast->remaining)
best_ast->packet_size=
best_ast->remaining= best_st->index_entries[i].size;
}
else
return AVERROR_EOF;
}
resync:
if(avi->stream_index >= 0){
AVStream *st= s->streams[ avi->stream_index ];
AVIStream *ast= st->priv_data;
int size, err;
if(get_subtitle_pkt(s, st, pkt))
return 0;
if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
size= INT_MAX;
else if(ast->sample_size < 32)
// arbitrary multiplier to avoid tiny packets for raw PCM data
size= 1024*ast->sample_size;
else
size= ast->sample_size;
if(size > ast->remaining)
size= ast->remaining;
avi->last_pkt_pos= avio_tell(pb);
err= av_get_packet(pb, pkt, size);
if(err<0)
return err;
if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){
uint8_t *pal;
pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);
if(!pal){
av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");
}else{
memcpy(pal, ast->pal, AVPALETTE_SIZE);
ast->has_pal = 0;
}
}
if (CONFIG_DV_DEMUXER && avi->dv_demux) {
dstr = pkt->destruct;
size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
pkt->data, pkt->size, pkt->pos);
pkt->destruct = dstr;
pkt->flags |= AV_PKT_FLAG_KEY;
if (size < 0)
av_free_packet(pkt);
} else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE
&& !st->codec->codec_tag && read_gab2_sub(st, pkt)) {
ast->frame_offset++;
avi->stream_index = -1;
ast->remaining = 0;
goto resync;
} else {
/* XXX: How to handle B-frames in AVI? */
pkt->dts = ast->frame_offset;
// pkt->dts += ast->start;
if(ast->sample_size)
pkt->dts /= ast->sample_size;
//av_log(s, AV_LOG_DEBUG, "dts:%"PRId64" offset:%"PRId64" %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);
pkt->stream_index = avi->stream_index;
if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
AVIndexEntry *e;
int index;
assert(st->index_entries);
index= av_index_search_timestamp(st, ast->frame_offset, 0);
e= &st->index_entries[index];
if(index >= 0 && e->timestamp == ast->frame_offset){
if (index == st->nb_index_entries-1){
int key=1;
int i;
uint32_t state=-1;
for(i=0; i<FFMIN(size,256); i++){
if(st->codec->codec_id == CODEC_ID_MPEG4){
if(state == 0x1B6){
key= !(pkt->data[i]&0xC0);
break;
}
}else
break;
state= (state<<8) + pkt->data[i];
}
if(!key)
e->flags &= ~AVINDEX_KEYFRAME;
}
if (e->flags & AVINDEX_KEYFRAME)
pkt->flags |= AV_PKT_FLAG_KEY;
}
} else {
pkt->flags |= AV_PKT_FLAG_KEY;
}
ast->frame_offset += get_duration(ast, pkt->size);
}
ast->remaining -= size;
if(!ast->remaining){
avi->stream_index= -1;
ast->packet_size= 0;
}
if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){
av_free_packet(pkt);
goto resync;
}
ast->seek_pos= 0;
if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){
int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);
if(avi->dts_max - dts > 2*AV_TIME_BASE){
avi->non_interleaved= 1;
av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");
}else if(avi->dts_max < dts)
avi->dts_max = dts;
}
return size;
}
if ((err = avi_sync(s, 0)) < 0)
return err;
goto resync;
}
/* XXX: We make the implicit supposition that the positions are sorted
for each stream. */
static int avi_read_idx1(AVFormatContext *s, int size)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
int nb_index_entries, i;
AVStream *st;
AVIStream *ast;
unsigned int index, tag, flags, pos, len, first_packet = 1;
unsigned last_pos= -1;
int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
nb_index_entries = size / 16;
if (nb_index_entries <= 0)
return -1;
idx1_pos = avio_tell(pb);
avio_seek(pb, avi->movi_list+4, SEEK_SET);
if (avi_sync(s, 1) == 0) {
first_packet_pos = avio_tell(pb) - 8;
}
avi->stream_index = -1;
avio_seek(pb, idx1_pos, SEEK_SET);
/* Read the entries and sort them in each stream component. */
for(i = 0; i < nb_index_entries; i++) {
if(url_feof(pb))
return -1;
tag = avio_rl32(pb);
flags = avio_rl32(pb);
pos = avio_rl32(pb);
len = avio_rl32(pb);
av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
i, tag, flags, pos, len);
index = ((tag & 0xff) - '0') * 10;
index += ((tag >> 8) & 0xff) - '0';
if (index >= s->nb_streams)
continue;
st = s->streams[index];
ast = st->priv_data;
if(first_packet && first_packet_pos && len) {
data_offset = first_packet_pos - pos;
first_packet = 0;
}
pos += data_offset;
av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
if(last_pos == pos)
avi->non_interleaved= 1;
else if(len || !ast->sample_size)
av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
ast->cum_len += get_duration(ast, len);
last_pos= pos;
}
return 0;
}
static int guess_ni_flag(AVFormatContext *s){
int i;
int64_t last_start=0;
int64_t first_end= INT64_MAX;
int64_t oldpos= avio_tell(s->pb);
for(i=0; i<s->nb_streams; i++){
AVStream *st = s->streams[i];
int n= st->nb_index_entries;
unsigned int size;
if(n <= 0)
continue;
if(n >= 2){
int64_t pos= st->index_entries[0].pos;
avio_seek(s->pb, pos + 4, SEEK_SET);
size= avio_rl32(s->pb);
if(pos + size > st->index_entries[1].pos)
last_start= INT64_MAX;
}
if(st->index_entries[0].pos > last_start)
last_start= st->index_entries[0].pos;
if(st->index_entries[n-1].pos < first_end)
first_end= st->index_entries[n-1].pos;
}
avio_seek(s->pb, oldpos, SEEK_SET);
return last_start > first_end;
}
static int avi_load_index(AVFormatContext *s)
{
AVIContext *avi = s->priv_data;
AVIOContext *pb = s->pb;
uint32_t tag, size;
int64_t pos= avio_tell(pb);
int ret = -1;
if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
goto the_end; // maybe truncated file
av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
for(;;) {
if (url_feof(pb))
break;
tag = avio_rl32(pb);
size = avio_rl32(pb);
av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
tag & 0xff,
(tag >> 8) & 0xff,
(tag >> 16) & 0xff,
(tag >> 24) & 0xff,
size);
if (tag == MKTAG('i', 'd', 'x', '1') &&
avi_read_idx1(s, size) >= 0) {
avi->index_loaded=2;
ret = 0;
break;
}
size += (size & 1);
if (avio_skip(pb, size) < 0)
break; // something is wrong here
}
the_end:
avio_seek(pb, pos, SEEK_SET);
return ret;
}
static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
{
AVIStream *ast2 = st2->priv_data;
int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
av_free_packet(&ast2->sub_pkt);
if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
av_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
}
static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
{
AVIContext *avi = s->priv_data;
AVStream *st;
int i, index;
int64_t pos, pos_min;
AVIStream *ast;
if (!avi->index_loaded) {
/* we only load the index on demand */
avi_load_index(s);
avi->index_loaded |= 1;
}
assert(stream_index>= 0);
st = s->streams[stream_index];
ast= st->priv_data;
index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);
if(index<0)
return -1;
/* find the position */
pos = st->index_entries[index].pos;
timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
// av_log(s, AV_LOG_DEBUG, "XX %"PRId64" %d %"PRId64"\n", timestamp, index, st->index_entries[index].timestamp);
if (CONFIG_DV_DEMUXER && avi->dv_demux) {
/* One and only one real stream for DV in AVI, and it has video */
/* offsets. Calling with other stream indexes should have failed */
/* the av_index_search_timestamp call above. */
assert(stream_index == 0);
if(avio_seek(s->pb, pos, SEEK_SET) < 0)
return -1;
/* Feed the DV video stream version of the timestamp to the */
/* DV demux so it can synthesize correct timestamps. */
dv_offset_reset(avi->dv_demux, timestamp);
avi->stream_index= -1;
return 0;
}
pos_min= pos;
for(i = 0; i < s->nb_streams; i++) {
AVStream *st2 = s->streams[i];
AVIStream *ast2 = st2->priv_data;
ast2->packet_size=
ast2->remaining= 0;
if (ast2->sub_ctx) {
seek_subtitle(st, st2, timestamp);
continue;
}
if (st2->nb_index_entries <= 0)
continue;
// assert(st2->codec->block_align);
assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);
index = av_index_search_timestamp(
st2,
av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));
if(index<0)
index=0;
ast2->seek_pos= st2->index_entries[index].pos;
pos_min= FFMIN(pos_min,ast2->seek_pos);
}
for(i = 0; i < s->nb_streams; i++) {
AVStream *st2 = s->streams[i];
AVIStream *ast2 = st2->priv_data;
if (ast2->sub_ctx || st2->nb_index_entries <= 0)
continue;
index = av_index_search_timestamp(
st2,
av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));
if(index<0)
index=0;
while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)
index--;
ast2->frame_offset = st2->index_entries[index].timestamp;
}
/* do the seek */
if (avio_seek(s->pb, pos_min, SEEK_SET) < 0)
return -1;
avi->stream_index= -1;
avi->dts_max= INT_MIN;
return 0;
}
static int avi_read_close(AVFormatContext *s)
{
int i;
AVIContext *avi = s->priv_data;
for(i=0;i<s->nb_streams;i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
if (ast) {
if (ast->sub_ctx) {
av_freep(&ast->sub_ctx->pb);
av_close_input_file(ast->sub_ctx);
}
av_free(ast->sub_buffer);
av_free_packet(&ast->sub_pkt);
}
}
av_free(avi->dv_demux);
return 0;
}
static int avi_probe(AVProbeData *p)
{
int i;
/* check file header */
for(i=0; avi_headers[i][0]; i++)
if(!memcmp(p->buf , avi_headers[i] , 4) &&
!memcmp(p->buf+8, avi_headers[i]+4, 4))
return AVPROBE_SCORE_MAX;
return 0;
}
AVInputFormat ff_avi_demuxer = {
.name = "avi",
.long_name = NULL_IF_CONFIG_SMALL("AVI format"),
.priv_data_size = sizeof(AVIContext),
.read_probe = avi_probe,
.read_header = avi_read_header,
.read_packet = avi_read_packet,
.read_close = avi_read_close,
.read_seek = avi_read_seek,
.priv_class = &demuxer_class,
};