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/*
* FLV encoder.
* Copyright (c) 2003 The FFmpeg Project.
*
* 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"
unsigned int get_be24(ByteIOContext *s)
{
unsigned int val;
val = get_byte(s) << 16;
val |= get_byte(s) << 8;
val |= get_byte(s);
return val;
}
static int flv_probe(AVProbeData *p)
{
const uint8_t *d;
if (p->buf_size < 6)
return 0;
d = p->buf;
if (d[0] == 'F' && d[1] == 'L' && d[2] == 'V') {
return 50;
}
return 0;
}
static int flv_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
int offset, flags;
AVStream *st;
s->ctx_flags |= AVFMTCTX_NOHEADER; //ok we have a header but theres no fps, codec type, sample_rate, ...
url_fskip(&s->pb, 4);
flags = get_byte(&s->pb);
offset = get_be32(&s->pb);
url_fseek(&s->pb, offset, SEEK_SET);
return 0;
}
static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret, i, type, size, pts, flags, is_audio;
AVStream *st;
for(;;){
url_fskip(&s->pb, 4); /* size of previous packet */
type = get_byte(&s->pb);
size = get_be24(&s->pb);
pts = get_be24(&s->pb);
// av_log(s, AV_LOG_DEBUG, "type:%d, size:%d, pts:%d\n", type, size, pts);
if (url_feof(&s->pb))
return AVERROR_IO;
url_fskip(&s->pb, 4); /* reserved */
flags = 0;
if(size == 0)
continue;
if (type == 8) {
is_audio=1;
flags = get_byte(&s->pb);
size--;
} else if (type == 9) {
is_audio=0;
flags = get_byte(&s->pb);
size--;
} else {
/* skip packet */
av_log(s, AV_LOG_ERROR, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags);
url_fskip(&s->pb, size);
continue;
}
/* now find stream */
for(i=0;i<s->nb_streams;i++) {
st = s->streams[i];
if (st->id == is_audio)
break;
}
if(i == s->nb_streams){
st = av_new_stream(s, is_audio);
if (!st)
return AVERROR_NOMEM;
av_set_pts_info(st, 24, 1, 1000); /* 24 bit pts in ms */
st->codec.frame_rate_base= 0;
}
break;
}
if(is_audio){
if(st->codec.sample_rate == 0){
st->codec.codec_type = CODEC_TYPE_AUDIO;
st->codec.channels = (flags&1)+1;
if((flags >> 4) == 5)
st->codec.sample_rate= 8000;
else
st->codec.sample_rate = (44100<<((flags>>2)&3))>>3;
switch(flags >> 4){/* 0: uncompressed 1: ADPCM 2: mp3 5: Nellymoser 8kHz mono 6: Nellymoser*/
case 2: st->codec.codec_id = CODEC_ID_MP3; break;
default:
st->codec.codec_tag= (flags >> 4);
}
}
}else{
if(st->codec.frame_rate_base == 0){
st->codec.codec_type = CODEC_TYPE_VIDEO;
//guess the frame rate
if(pts){
st->codec.frame_rate_base=1;
st->codec.frame_rate= (1000 + pts/2)/pts;
}
switch(flags & 0xF){
case 2: st->codec.codec_id = CODEC_ID_FLV1; break;
default:
st->codec.codec_tag= flags & 0xF;
}
}
}
if (av_new_packet(pkt, size) < 0)
return AVERROR_IO;
ret = get_buffer(&s->pb, pkt->data, size);
if (ret <= 0) {
av_free_packet(pkt);
return AVERROR_IO;
}
/* note: we need to modify the packet size here to handle the last
packet */
pkt->size = ret;
pkt->pts = pts;
pkt->stream_index = st->index;
return ret;
}
static int flv_read_close(AVFormatContext *s)
{
return 0;
}
AVInputFormat flv_iformat = {
"flv",
"flv format",
0,
flv_probe,
flv_read_header,
flv_read_packet,
flv_read_close,
.extensions = "flv",
.value = CODEC_ID_FLV1,
};
int flvdec_init(void)
{
av_register_input_format(&flv_iformat);
return 0;
}
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