mirror of https://git.ffmpeg.org/ffmpeg.git
254 lines
7.3 KiB
C
254 lines
7.3 KiB
C
/*
|
|
* AVI decoder.
|
|
* Copyright (c) 2001 Gerard Lantau.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
#include "avformat.h"
|
|
#include "avi.h"
|
|
|
|
//#define DEBUG
|
|
|
|
typedef struct AVIIndex {
|
|
unsigned char tag[4];
|
|
unsigned int flags, pos, len;
|
|
struct AVIIndex *next;
|
|
} AVIIndex;
|
|
|
|
typedef struct {
|
|
INT64 movi_end;
|
|
offset_t movi_list;
|
|
AVIIndex *first, *last;
|
|
} AVIContext;
|
|
|
|
#ifdef DEBUG
|
|
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
|
|
|
|
int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
|
|
{
|
|
AVIContext *avi;
|
|
ByteIOContext *pb = &s->pb;
|
|
UINT32 tag, tag1;
|
|
int codec_type, stream_index, size, frame_period, bit_rate;
|
|
int i, bps;
|
|
AVStream *st;
|
|
|
|
avi = malloc(sizeof(AVIContext));
|
|
if (!avi)
|
|
return -1;
|
|
memset(avi, 0, sizeof(AVIContext));
|
|
s->priv_data = avi;
|
|
|
|
/* check RIFF header */
|
|
tag = get_le32(pb);
|
|
|
|
if (tag != MKTAG('R', 'I', 'F', 'F'))
|
|
return -1;
|
|
get_le32(pb); /* file size */
|
|
tag = get_le32(pb);
|
|
if (tag != MKTAG('A', 'V', 'I', ' '))
|
|
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_end = url_ftell(pb) + size - 4;
|
|
#ifdef DEBUG
|
|
printf("movi end=%Lx\n", avi->movi_end);
|
|
#endif
|
|
goto end_of_header;
|
|
}
|
|
break;
|
|
case MKTAG('a', 'v', 'i', 'h'):
|
|
/* avi header */
|
|
frame_period = get_le32(pb);
|
|
bit_rate = get_le32(pb) * 8;
|
|
url_fskip(pb, 4 * 4);
|
|
s->nb_streams = get_le32(pb);
|
|
for(i=0;i<s->nb_streams;i++) {
|
|
AVStream *st;
|
|
st = malloc(sizeof(AVStream));
|
|
if (!st)
|
|
goto fail;
|
|
memset(st, 0, sizeof(AVStream));
|
|
s->streams[i] = st;
|
|
}
|
|
url_fskip(pb, size - 7 * 4);
|
|
break;
|
|
case MKTAG('s', 't', 'r', 'h'):
|
|
/* stream header */
|
|
stream_index++;
|
|
tag1 = get_le32(pb);
|
|
switch(tag1) {
|
|
case MKTAG('v', 'i', 'd', 's'):
|
|
codec_type = CODEC_TYPE_VIDEO;
|
|
get_le32(pb); /* codec tag */
|
|
get_le32(pb); /* flags */
|
|
get_le16(pb); /* priority */
|
|
get_le16(pb); /* language */
|
|
get_le32(pb); /* XXX: initial frame ? */
|
|
get_le32(pb); /* scale */
|
|
get_le32(pb); /* rate */
|
|
url_fskip(pb, size - 7 * 4);
|
|
break;
|
|
case MKTAG('a', 'u', 'd', 's'):
|
|
codec_type = CODEC_TYPE_AUDIO;
|
|
/* nothing really useful */
|
|
url_fskip(pb, size - 4);
|
|
break;
|
|
default:
|
|
goto fail;
|
|
}
|
|
break;
|
|
case MKTAG('s', 't', 'r', 'f'):
|
|
/* stream header */
|
|
if (stream_index >= s->nb_streams) {
|
|
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);
|
|
if (frame_period)
|
|
st->codec.frame_rate = (INT64_C(1000000) * FRAME_RATE_BASE) / frame_period;
|
|
else
|
|
st->codec.frame_rate = 25 * FRAME_RATE_BASE;
|
|
get_le16(pb); /* panes */
|
|
get_le16(pb); /* depth */
|
|
tag1 = get_le32(pb);
|
|
#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);
|
|
url_fskip(pb, size - 5 * 4);
|
|
break;
|
|
case CODEC_TYPE_AUDIO:
|
|
tag1 = get_le16(pb);
|
|
st->codec.codec_type = CODEC_TYPE_AUDIO;
|
|
st->codec.codec_tag = tag1;
|
|
#ifdef DEBUG
|
|
printf("audio: 0x%x\n", tag1);
|
|
#endif
|
|
st->codec.channels = get_le16(pb);
|
|
st->codec.sample_rate = get_le32(pb);
|
|
st->codec.bit_rate = get_le32(pb) * 8;
|
|
get_le16(pb); /* block align */
|
|
bps = get_le16(pb);
|
|
st->codec.codec_id = wav_codec_get_id(tag1, bps);
|
|
url_fskip(pb, size - 4 * 4);
|
|
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++) {
|
|
if (s->streams[i])
|
|
free(s->streams[i]);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
AVIContext *avi = s->priv_data;
|
|
ByteIOContext *pb = &s->pb;
|
|
int n, d1, d2, size;
|
|
|
|
find_next:
|
|
if (url_feof(pb) || url_ftell(pb) >= avi->movi_end)
|
|
return -1;
|
|
d1 = get_byte(pb);
|
|
if (d1 < '0' || d1 > '9')
|
|
goto find_next;
|
|
d2 = get_byte(pb);
|
|
if (d2 < '0' || d2 > '9')
|
|
goto find_next;
|
|
n = (d1 - '0') * 10 + (d2 - '0');
|
|
|
|
if (n < 0 || n >= s->nb_streams)
|
|
goto find_next;
|
|
|
|
d1 = get_byte(pb);
|
|
d2 = get_byte(pb);
|
|
if ((d1 != 'd' && d2 != 'c') &&
|
|
(d1 != 'w' && d2 != 'b'))
|
|
goto find_next;
|
|
|
|
size = get_le32(pb);
|
|
av_new_packet(pkt, size);
|
|
pkt->stream_index = n;
|
|
|
|
get_buffer(pb, pkt->data, pkt->size);
|
|
|
|
if (size & 1)
|
|
get_byte(pb);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int avi_read_close(AVFormatContext *s)
|
|
{
|
|
AVIContext *avi = s->priv_data;
|
|
free(avi);
|
|
return 0;
|
|
}
|