mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-02 03:06:28 +02:00
715 lines
22 KiB
C
715 lines
22 KiB
C
/*
|
|
* AVI decoder.
|
|
* Copyright (c) 2001 Fabrice Bellard.
|
|
*
|
|
* This library 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 of the License, or (at your option) any later version.
|
|
*
|
|
* This library 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 this library; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
#include "avformat.h"
|
|
#include "avi.h"
|
|
#include "dv.h"
|
|
|
|
//#define DEBUG
|
|
//#define DEBUG_SEEK
|
|
|
|
typedef struct AVIIndexEntry {
|
|
unsigned int flags;
|
|
unsigned int pos;
|
|
unsigned int cum_len; /* sum of all lengths before this packet */
|
|
} AVIIndexEntry;
|
|
|
|
typedef struct AVIStream {
|
|
AVIIndexEntry *index_entries;
|
|
int nb_index_entries;
|
|
int index_entries_allocated_size;
|
|
int frame_offset; /* current frame (video) or byte (audio) counter
|
|
(used to compute the pts) */
|
|
int scale;
|
|
int rate;
|
|
int sample_size; /* audio only data */
|
|
int start;
|
|
|
|
int new_frame_offset; /* temporary storage (used during seek) */
|
|
int cum_len; /* temporary storage (used during seek) */
|
|
} AVIStream;
|
|
|
|
typedef struct {
|
|
int64_t riff_end;
|
|
int64_t movi_end;
|
|
offset_t movi_list;
|
|
int index_loaded;
|
|
DVDemuxContext* dv_demux;
|
|
} AVIContext;
|
|
|
|
#ifdef DEBUG
|
|
static void print_tag(const char *str, unsigned int tag, int size)
|
|
{
|
|
printf("%s: tag=%c%c%c%c size=0x%x\n",
|
|
str, tag & 0xff,
|
|
(tag >> 8) & 0xff,
|
|
(tag >> 16) & 0xff,
|
|
(tag >> 24) & 0xff,
|
|
size);
|
|
}
|
|
#endif
|
|
|
|
static int get_riff(AVIContext *avi, ByteIOContext *pb)
|
|
{
|
|
uint32_t tag;
|
|
/* check RIFF header */
|
|
tag = get_le32(pb);
|
|
|
|
if (tag != MKTAG('R', 'I', 'F', 'F'))
|
|
return -1;
|
|
avi->riff_end = get_le32(pb); /* RIFF chunk size */
|
|
avi->riff_end += url_ftell(pb); /* RIFF chunk end */
|
|
tag = get_le32(pb);
|
|
if (tag != MKTAG('A', 'V', 'I', ' ') && tag != MKTAG('A', 'V', 'I', 'X'))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
|
|
{
|
|
AVIContext *avi = s->priv_data;
|
|
ByteIOContext *pb = &s->pb;
|
|
uint32_t tag, tag1, handler;
|
|
int codec_type, stream_index, frame_period, bit_rate, scale, rate;
|
|
unsigned int size, nb_frames;
|
|
int i, n;
|
|
AVStream *st;
|
|
AVIStream *ast;
|
|
int xan_video = 0; /* hack to support Xan A/V */
|
|
|
|
if (get_riff(avi, pb) < 0)
|
|
return -1;
|
|
|
|
/* first list tag */
|
|
stream_index = -1;
|
|
codec_type = -1;
|
|
frame_period = 0;
|
|
for(;;) {
|
|
if (url_feof(pb))
|
|
goto fail;
|
|
tag = get_le32(pb);
|
|
size = get_le32(pb);
|
|
#ifdef DEBUG
|
|
print_tag("tag", tag, size);
|
|
#endif
|
|
|
|
switch(tag) {
|
|
case MKTAG('L', 'I', 'S', 'T'):
|
|
/* ignored, except when start of video packets */
|
|
tag1 = get_le32(pb);
|
|
#ifdef DEBUG
|
|
print_tag("list", tag1, 0);
|
|
#endif
|
|
if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
|
|
avi->movi_list = url_ftell(pb) - 4;
|
|
avi->movi_end = avi->movi_list + size;
|
|
#ifdef DEBUG
|
|
printf("movi end=%Lx\n", avi->movi_end);
|
|
#endif
|
|
goto end_of_header;
|
|
}
|
|
break;
|
|
case MKTAG('a', 'v', 'i', 'h'):
|
|
/* avi header */
|
|
/* using frame_period is bad idea */
|
|
frame_period = get_le32(pb);
|
|
bit_rate = get_le32(pb) * 8;
|
|
url_fskip(pb, 4 * 4);
|
|
n = get_le32(pb);
|
|
for(i=0;i<n;i++) {
|
|
AVIStream *ast;
|
|
st = av_new_stream(s, i);
|
|
if (!st)
|
|
goto fail;
|
|
|
|
ast = av_mallocz(sizeof(AVIStream));
|
|
if (!ast)
|
|
goto fail;
|
|
st->priv_data = ast;
|
|
}
|
|
url_fskip(pb, size - 7 * 4);
|
|
break;
|
|
case MKTAG('s', 't', 'r', 'h'):
|
|
/* stream header */
|
|
stream_index++;
|
|
tag1 = get_le32(pb);
|
|
handler = get_le32(pb); /* codec tag */
|
|
switch(tag1) {
|
|
case MKTAG('i', 'a', 'v', 's'):
|
|
case MKTAG('i', 'v', 'a', 's'):
|
|
/*
|
|
* After some consideration -- I don't think we
|
|
* have to support anything but DV in a 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;
|
|
|
|
av_freep(&s->streams[0]->codec.extradata);
|
|
av_freep(&s->streams[0]);
|
|
s->nb_streams = 0;
|
|
avi->dv_demux = dv_init_demux(s);
|
|
if (!avi->dv_demux)
|
|
goto fail;
|
|
stream_index = s->nb_streams - 1;
|
|
url_fskip(pb, size - 8);
|
|
break;
|
|
case MKTAG('v', 'i', 'd', 's'):
|
|
codec_type = CODEC_TYPE_VIDEO;
|
|
|
|
if (stream_index >= s->nb_streams) {
|
|
url_fskip(pb, size - 8);
|
|
break;
|
|
}
|
|
|
|
st = s->streams[stream_index];
|
|
ast = st->priv_data;
|
|
st->codec.stream_codec_tag= handler;
|
|
|
|
get_le32(pb); /* flags */
|
|
get_le16(pb); /* priority */
|
|
get_le16(pb); /* language */
|
|
get_le32(pb); /* XXX: initial frame ? */
|
|
scale = get_le32(pb); /* scale */
|
|
rate = get_le32(pb); /* rate */
|
|
|
|
if(scale && rate){
|
|
}else if(frame_period){
|
|
rate = 1000000;
|
|
scale = frame_period;
|
|
}else{
|
|
rate = 25;
|
|
scale = 1;
|
|
}
|
|
ast->rate = rate;
|
|
ast->scale = scale;
|
|
av_set_pts_info(st, 64, scale, rate);
|
|
st->codec.frame_rate = rate;
|
|
st->codec.frame_rate_base = scale;
|
|
get_le32(pb); /* start */
|
|
nb_frames = get_le32(pb);
|
|
st->start_time = 0;
|
|
st->duration = av_rescale(nb_frames,
|
|
st->codec.frame_rate_base * AV_TIME_BASE,
|
|
st->codec.frame_rate);
|
|
url_fskip(pb, size - 9 * 4);
|
|
break;
|
|
case MKTAG('a', 'u', 'd', 's'):
|
|
{
|
|
unsigned int length;
|
|
|
|
codec_type = CODEC_TYPE_AUDIO;
|
|
|
|
if (stream_index >= s->nb_streams) {
|
|
url_fskip(pb, size - 8);
|
|
break;
|
|
}
|
|
st = s->streams[stream_index];
|
|
ast = st->priv_data;
|
|
|
|
get_le32(pb); /* flags */
|
|
get_le16(pb); /* priority */
|
|
get_le16(pb); /* language */
|
|
get_le32(pb); /* initial frame */
|
|
ast->scale = get_le32(pb); /* scale */
|
|
ast->rate = get_le32(pb);
|
|
av_set_pts_info(st, 64, ast->scale, ast->rate);
|
|
ast->start= get_le32(pb); /* start */
|
|
length = get_le32(pb); /* length, in samples or bytes */
|
|
get_le32(pb); /* buffer size */
|
|
get_le32(pb); /* quality */
|
|
ast->sample_size = get_le32(pb); /* sample ssize */
|
|
//av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d\n", ast->scale, ast->rate, ast->sample_size, ast->start);
|
|
st->start_time = 0;
|
|
if (ast->rate != 0)
|
|
st->duration = (int64_t)length * AV_TIME_BASE / ast->rate;
|
|
url_fskip(pb, size - 12 * 4);
|
|
}
|
|
break;
|
|
default:
|
|
goto fail;
|
|
}
|
|
break;
|
|
case MKTAG('s', 't', 'r', 'f'):
|
|
/* stream header */
|
|
if (stream_index >= s->nb_streams || avi->dv_demux) {
|
|
url_fskip(pb, size);
|
|
} else {
|
|
st = s->streams[stream_index];
|
|
switch(codec_type) {
|
|
case CODEC_TYPE_VIDEO:
|
|
get_le32(pb); /* size */
|
|
st->codec.width = get_le32(pb);
|
|
st->codec.height = get_le32(pb);
|
|
get_le16(pb); /* panes */
|
|
st->codec.bits_per_sample= get_le16(pb); /* depth */
|
|
tag1 = get_le32(pb);
|
|
get_le32(pb); /* ImageSize */
|
|
get_le32(pb); /* XPelsPerMeter */
|
|
get_le32(pb); /* YPelsPerMeter */
|
|
get_le32(pb); /* ClrUsed */
|
|
get_le32(pb); /* ClrImportant */
|
|
|
|
st->codec.extradata_size= size - 10*4;
|
|
st->codec.extradata= av_malloc(st->codec.extradata_size);
|
|
get_buffer(pb, st->codec.extradata, st->codec.extradata_size);
|
|
|
|
if(st->codec.extradata_size & 1) //FIXME check if the encoder really did this correctly
|
|
get_byte(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_sample <= 8)) {
|
|
st->codec.palctrl = av_mallocz(sizeof(AVPaletteControl));
|
|
#ifdef WORDS_BIGENDIAN
|
|
for (i = 0; i < FFMIN(st->codec.extradata_size, AVPALETTE_SIZE)/4; i++)
|
|
st->codec.palctrl->palette[i] = bswap_32(((uint32_t*)st->codec.extradata)[i]);
|
|
#else
|
|
memcpy(st->codec.palctrl->palette, st->codec.extradata,
|
|
FFMIN(st->codec.extradata_size, AVPALETTE_SIZE));
|
|
#endif
|
|
st->codec.palctrl->palette_changed = 1;
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
print_tag("video", tag1, 0);
|
|
#endif
|
|
st->codec.codec_type = CODEC_TYPE_VIDEO;
|
|
st->codec.codec_tag = tag1;
|
|
st->codec.codec_id = codec_get_id(codec_bmp_tags, tag1);
|
|
if (st->codec.codec_id == CODEC_ID_XAN_WC4)
|
|
xan_video = 1;
|
|
// url_fskip(pb, size - 5 * 4);
|
|
break;
|
|
case CODEC_TYPE_AUDIO:
|
|
get_wav_header(pb, &st->codec, size);
|
|
if (size%2) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
|
|
url_fskip(pb, 1);
|
|
/* special case time: To support Xan DPCM, hardcode
|
|
* the format if Xxan is the video codec */
|
|
st->need_parsing = 1;
|
|
/* force parsing as several audio frames can be in
|
|
one packet */
|
|
if (xan_video)
|
|
st->codec.codec_id = CODEC_ID_XAN_DPCM;
|
|
break;
|
|
default:
|
|
url_fskip(pb, size);
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
/* skip tag */
|
|
size += (size & 1);
|
|
url_fskip(pb, size);
|
|
break;
|
|
}
|
|
}
|
|
end_of_header:
|
|
/* check stream number */
|
|
if (stream_index != s->nb_streams - 1) {
|
|
fail:
|
|
for(i=0;i<s->nb_streams;i++) {
|
|
av_freep(&s->streams[i]->codec.extradata);
|
|
av_freep(&s->streams[i]);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
AVIContext *avi = s->priv_data;
|
|
ByteIOContext *pb = &s->pb;
|
|
int n, d[8], size, i;
|
|
void* dstr;
|
|
|
|
memset(d, -1, sizeof(int)*8);
|
|
|
|
if (avi->dv_demux) {
|
|
size = dv_get_packet(avi->dv_demux, pkt);
|
|
if (size >= 0)
|
|
return size;
|
|
}
|
|
|
|
for(i=url_ftell(pb); !url_feof(pb); i++) {
|
|
int j;
|
|
|
|
if (i >= avi->movi_end) { /* Let's see if it's an OpenDML AVI */
|
|
uint32_t tag, size, tag2;
|
|
url_fskip(pb, avi->riff_end - url_ftell(pb));
|
|
if (get_riff(avi, pb) < 0)
|
|
return -1;
|
|
|
|
tag = get_le32(pb);
|
|
size = get_le32(pb);
|
|
tag2 = get_le32(pb);
|
|
if (tag == MKTAG('L','I','S','T') && tag2 == MKTAG('m','o','v','i'))
|
|
avi->movi_end = url_ftell(pb) + size - 4;
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
for(j=0; j<7; j++)
|
|
d[j]= d[j+1];
|
|
d[7]= get_byte(pb);
|
|
|
|
size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
|
|
|
|
//parse ix##
|
|
n= (d[2] - '0') * 10 + (d[3] - '0');
|
|
if( d[2] >= '0' && d[2] <= '9'
|
|
&& d[3] >= '0' && d[3] <= '9'
|
|
&& d[0] == 'i' && d[1] == 'x'
|
|
&& n < s->nb_streams
|
|
&& i + size <= avi->movi_end){
|
|
|
|
url_fskip(pb, size);
|
|
}
|
|
|
|
//parse ##dc/##wb
|
|
n= (d[0] - '0') * 10 + (d[1] - '0');
|
|
if( d[0] >= '0' && d[0] <= '9'
|
|
&& d[1] >= '0' && d[1] <= '9'
|
|
&& ((d[2] == 'd' && d[3] == 'c') ||
|
|
(d[2] == 'w' && d[3] == 'b') ||
|
|
(d[2] == 'd' && d[3] == 'b') ||
|
|
(d[2] == '_' && d[3] == '_'))
|
|
&& n < s->nb_streams
|
|
&& i + size <= avi->movi_end) {
|
|
|
|
av_new_packet(pkt, size);
|
|
get_buffer(pb, pkt->data, size);
|
|
if (size & 1) {
|
|
get_byte(pb);
|
|
size++;
|
|
}
|
|
|
|
if (avi->dv_demux) {
|
|
dstr = pkt->destruct;
|
|
size = dv_produce_packet(avi->dv_demux, pkt,
|
|
pkt->data, pkt->size);
|
|
pkt->destruct = dstr;
|
|
pkt->flags |= PKT_FLAG_KEY;
|
|
} else {
|
|
AVStream *st;
|
|
AVIStream *ast;
|
|
st = s->streams[n];
|
|
ast = st->priv_data;
|
|
|
|
/* XXX: how to handle B frames in avi ? */
|
|
pkt->pts = ast->frame_offset;
|
|
if(ast->sample_size)
|
|
pkt->pts /= ast->sample_size;
|
|
//printf("%Ld %d %d %d %d\n", pkt->pts, ast->frame_offset, ast->scale, AV_TIME_BASE, ast->rate);
|
|
pkt->stream_index = n;
|
|
/* FIXME: We really should read index for that */
|
|
if (st->codec.codec_type == CODEC_TYPE_VIDEO) {
|
|
if (ast->frame_offset < ast->nb_index_entries) {
|
|
if (ast->index_entries[ast->frame_offset].flags & AVIIF_INDEX)
|
|
pkt->flags |= PKT_FLAG_KEY;
|
|
} else {
|
|
/* if no index, better to say that all frames
|
|
are key frames */
|
|
pkt->flags |= PKT_FLAG_KEY;
|
|
}
|
|
} else {
|
|
pkt->flags |= PKT_FLAG_KEY;
|
|
}
|
|
if(ast->sample_size)
|
|
ast->frame_offset += pkt->size;
|
|
else
|
|
ast->frame_offset++;
|
|
}
|
|
return size;
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/* XXX: we make the implicit supposition that the position are sorted
|
|
for each stream */
|
|
static int avi_read_idx1(AVFormatContext *s, int size)
|
|
{
|
|
ByteIOContext *pb = &s->pb;
|
|
int nb_index_entries, i;
|
|
AVStream *st;
|
|
AVIStream *ast;
|
|
AVIIndexEntry *ie, *entries;
|
|
unsigned int index, tag, flags, pos, len;
|
|
|
|
nb_index_entries = size / 16;
|
|
if (nb_index_entries <= 0)
|
|
return -1;
|
|
|
|
/* read the entries and sort them in each stream component */
|
|
for(i = 0; i < nb_index_entries; i++) {
|
|
tag = get_le32(pb);
|
|
flags = get_le32(pb);
|
|
pos = get_le32(pb);
|
|
len = get_le32(pb);
|
|
#if defined(DEBUG_SEEK) && 0
|
|
printf("%d: tag=0x%x flags=0x%x pos=0x%x len=%d\n",
|
|
i, tag, flags, pos, len);
|
|
#endif
|
|
index = ((tag & 0xff) - '0') * 10;
|
|
index += ((tag >> 8) & 0xff) - '0';
|
|
if (index >= s->nb_streams)
|
|
continue;
|
|
st = s->streams[index];
|
|
ast = st->priv_data;
|
|
|
|
entries = av_fast_realloc(ast->index_entries,
|
|
&ast->index_entries_allocated_size,
|
|
(ast->nb_index_entries + 1) *
|
|
sizeof(AVIIndexEntry));
|
|
if (entries) {
|
|
ast->index_entries = entries;
|
|
ie = &entries[ast->nb_index_entries++];
|
|
ie->flags = flags;
|
|
ie->pos = pos;
|
|
ie->cum_len = ast->cum_len;
|
|
ast->cum_len += len;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int avi_load_index(AVFormatContext *s)
|
|
{
|
|
AVIContext *avi = s->priv_data;
|
|
ByteIOContext *pb = &s->pb;
|
|
uint32_t tag, size;
|
|
offset_t pos= url_ftell(pb);
|
|
|
|
url_fseek(pb, avi->movi_end, SEEK_SET);
|
|
#ifdef DEBUG_SEEK
|
|
printf("movi_end=0x%llx\n", avi->movi_end);
|
|
#endif
|
|
for(;;) {
|
|
if (url_feof(pb))
|
|
break;
|
|
tag = get_le32(pb);
|
|
size = get_le32(pb);
|
|
#ifdef DEBUG_SEEK
|
|
printf("tag=%c%c%c%c size=0x%x\n",
|
|
tag & 0xff,
|
|
(tag >> 8) & 0xff,
|
|
(tag >> 16) & 0xff,
|
|
(tag >> 24) & 0xff,
|
|
size);
|
|
#endif
|
|
switch(tag) {
|
|
case MKTAG('i', 'd', 'x', '1'):
|
|
if (avi_read_idx1(s, size) < 0)
|
|
goto skip;
|
|
else
|
|
goto the_end;
|
|
break;
|
|
default:
|
|
skip:
|
|
size += (size & 1);
|
|
url_fskip(pb, size);
|
|
break;
|
|
}
|
|
}
|
|
the_end:
|
|
url_fseek(pb, pos, SEEK_SET);
|
|
return 0;
|
|
}
|
|
|
|
/* return the index entry whose position is immediately >= 'wanted_pos' */
|
|
static int locate_frame_in_index(AVIIndexEntry *entries,
|
|
int nb_entries, int wanted_pos)
|
|
{
|
|
int a, b, m, pos;
|
|
|
|
a = 0;
|
|
b = nb_entries - 1;
|
|
while (a <= b) {
|
|
m = (a + b) >> 1;
|
|
pos = entries[m].pos;
|
|
if (pos == wanted_pos)
|
|
goto found;
|
|
else if (pos > wanted_pos) {
|
|
b = m - 1;
|
|
} else {
|
|
a = m + 1;
|
|
}
|
|
}
|
|
m = a;
|
|
if (m > 0)
|
|
m--;
|
|
found:
|
|
return m;
|
|
}
|
|
|
|
static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp)
|
|
{
|
|
AVIContext *avi = s->priv_data;
|
|
AVStream *st;
|
|
AVIStream *ast;
|
|
int frame_number, i;
|
|
int64_t pos;
|
|
|
|
if (!avi->index_loaded) {
|
|
/* we only load the index on demand */
|
|
avi_load_index(s);
|
|
avi->index_loaded = 1;
|
|
}
|
|
if (stream_index < 0) {
|
|
for(i = 0; i < s->nb_streams; i++) {
|
|
st = s->streams[i];
|
|
if (st->codec.codec_type == CODEC_TYPE_VIDEO)
|
|
goto found;
|
|
}
|
|
return -1;
|
|
found:
|
|
stream_index = i;
|
|
}
|
|
|
|
st = s->streams[stream_index];
|
|
if (st->codec.codec_type != CODEC_TYPE_VIDEO)
|
|
return -1;
|
|
ast = st->priv_data;
|
|
/* compute the frame number */
|
|
frame_number = timestamp;
|
|
#ifdef DEBUG_SEEK
|
|
printf("timestamp=%0.3f nb_indexes=%d frame_number=%d\n",
|
|
(double)timestamp / AV_TIME_BASE,
|
|
ast->nb_index_entries, frame_number);
|
|
#endif
|
|
/* find a closest key frame before */
|
|
if (frame_number >= ast->nb_index_entries)
|
|
return -1;
|
|
while (frame_number >= 0 &&
|
|
!(ast->index_entries[frame_number].flags & AVIIF_INDEX))
|
|
frame_number--;
|
|
if (frame_number < 0)
|
|
return -1;
|
|
ast->new_frame_offset = frame_number;
|
|
|
|
/* find the position */
|
|
pos = ast->index_entries[frame_number].pos;
|
|
|
|
#ifdef DEBUG_SEEK
|
|
printf("key_frame_number=%d pos=0x%llx\n",
|
|
frame_number, pos);
|
|
#endif
|
|
|
|
/* update the frame counters for all the other stream by looking
|
|
at the positions just after the one found */
|
|
for(i = 0; i < s->nb_streams; i++) {
|
|
int j;
|
|
if (i != stream_index) {
|
|
st = s->streams[i];
|
|
ast = st->priv_data;
|
|
if (ast->nb_index_entries <= 0)
|
|
return -1;
|
|
j = locate_frame_in_index(ast->index_entries,
|
|
ast->nb_index_entries,
|
|
pos);
|
|
/* get next frame */
|
|
if ((j + 1) < ast->nb_index_entries)
|
|
j++;
|
|
/* extract the current frame number */
|
|
if (ast->sample_size==0)
|
|
ast->new_frame_offset = j;
|
|
else
|
|
ast->new_frame_offset = ast->index_entries[j].cum_len;
|
|
}
|
|
}
|
|
|
|
/* everything is OK now. We can update the frame offsets */
|
|
for(i = 0; i < s->nb_streams; i++) {
|
|
st = s->streams[i];
|
|
ast = st->priv_data;
|
|
ast->frame_offset = ast->new_frame_offset;
|
|
#ifdef DEBUG_SEEK
|
|
printf("%d: frame_offset=%d\n", i,
|
|
ast->frame_offset);
|
|
#endif
|
|
}
|
|
/* do the seek */
|
|
pos += avi->movi_list;
|
|
url_fseek(&s->pb, pos, SEEK_SET);
|
|
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){
|
|
av_free(ast->index_entries);
|
|
av_free(ast);
|
|
}
|
|
av_free(st->codec.extradata);
|
|
av_free(st->codec.palctrl);
|
|
}
|
|
|
|
if (avi->dv_demux)
|
|
av_free(avi->dv_demux);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int avi_probe(AVProbeData *p)
|
|
{
|
|
/* check file header */
|
|
if (p->buf_size <= 32)
|
|
return 0;
|
|
if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
|
|
p->buf[2] == 'F' && p->buf[3] == 'F' &&
|
|
p->buf[8] == 'A' && p->buf[9] == 'V' &&
|
|
p->buf[10] == 'I' && p->buf[11] == ' ')
|
|
return AVPROBE_SCORE_MAX;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
static AVInputFormat avi_iformat = {
|
|
"avi",
|
|
"avi format",
|
|
sizeof(AVIContext),
|
|
avi_probe,
|
|
avi_read_header,
|
|
avi_read_packet,
|
|
avi_read_close,
|
|
avi_read_seek,
|
|
};
|
|
|
|
int avidec_init(void)
|
|
{
|
|
av_register_input_format(&avi_iformat);
|
|
return 0;
|
|
}
|