mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-21 06:50:44 +00:00
141 lines
4.0 KiB
C
141 lines
4.0 KiB
C
/*
|
|
* Copyright (C) 2008 Ramiro Polla
|
|
*
|
|
* 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 "libavcodec/bytestream.h"
|
|
#include "avformat.h"
|
|
#include "internal.h"
|
|
|
|
#define HEADER_SIZE 24
|
|
|
|
/*
|
|
* Header structure:
|
|
* uint16_t ss; // struct size
|
|
* uint16_t width; // frame width
|
|
* uint16_t height; // frame height
|
|
* uint16_t ff; // keyframe + some other info(???)
|
|
* uint32_t size; // size of data
|
|
* uint32_t fourcc; // ML20
|
|
* uint32_t u3; // ?
|
|
* uint32_t ts; // time
|
|
*/
|
|
|
|
static int msnwc_tcp_probe(AVProbeData *p)
|
|
{
|
|
int i;
|
|
|
|
for(i = 0 ; i + HEADER_SIZE <= p->buf_size ; i++) {
|
|
uint16_t width, height;
|
|
uint32_t fourcc;
|
|
const uint8_t *bytestream = p->buf+i;
|
|
|
|
if(bytestream_get_le16(&bytestream) != HEADER_SIZE)
|
|
continue;
|
|
width = bytestream_get_le16(&bytestream);
|
|
height = bytestream_get_le16(&bytestream);
|
|
if(!(width==320 && height==240) && !(width==160 && height==120))
|
|
continue;
|
|
bytestream += 2; // keyframe
|
|
bytestream += 4; // size
|
|
fourcc = bytestream_get_le32(&bytestream);
|
|
if(fourcc != MKTAG('M', 'L', '2', '0'))
|
|
continue;
|
|
|
|
if(i) {
|
|
if(i < 14) /* starts with SwitchBoard connection info */
|
|
return AVPROBE_SCORE_MAX / 2;
|
|
else /* starts in the middle of stream */
|
|
return AVPROBE_SCORE_MAX / 3;
|
|
} else {
|
|
return AVPROBE_SCORE_MAX;
|
|
}
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
static int msnwc_tcp_read_header(AVFormatContext *ctx)
|
|
{
|
|
AVIOContext *pb = ctx->pb;
|
|
AVCodecContext *codec;
|
|
AVStream *st;
|
|
|
|
st = avformat_new_stream(ctx, NULL);
|
|
if(!st)
|
|
return AVERROR(ENOMEM);
|
|
|
|
codec = st->codec;
|
|
codec->codec_type = AVMEDIA_TYPE_VIDEO;
|
|
codec->codec_id = AV_CODEC_ID_MIMIC;
|
|
codec->codec_tag = MKTAG('M', 'L', '2', '0');
|
|
|
|
avpriv_set_pts_info(st, 32, 1, 1000);
|
|
|
|
/* Some files start with "connected\r\n\r\n".
|
|
* So skip until we find the first byte of struct size */
|
|
while(avio_r8(pb) != HEADER_SIZE && !url_feof(pb));
|
|
|
|
if(url_feof(pb)) {
|
|
av_log(ctx, AV_LOG_ERROR, "Could not find valid start.\n");
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int msnwc_tcp_read_packet(AVFormatContext *ctx, AVPacket *pkt)
|
|
{
|
|
AVIOContext *pb = ctx->pb;
|
|
uint16_t keyframe;
|
|
uint32_t size, timestamp;
|
|
|
|
avio_skip(pb, 1); /* one byte has been read ahead */
|
|
avio_skip(pb, 2);
|
|
avio_skip(pb, 2);
|
|
keyframe = avio_rl16(pb);
|
|
size = avio_rl32(pb);
|
|
avio_skip(pb, 4);
|
|
avio_skip(pb, 4);
|
|
timestamp = avio_rl32(pb);
|
|
|
|
if(!size || av_get_packet(pb, pkt, size) != size)
|
|
return -1;
|
|
|
|
avio_skip(pb, 1); /* Read ahead one byte of struct size like read_header */
|
|
|
|
pkt->pts = timestamp;
|
|
pkt->dts = timestamp;
|
|
pkt->stream_index = 0;
|
|
|
|
/* Some aMsn generated videos (or was it Mercury Messenger?) don't set
|
|
* this bit and rely on the codec to get keyframe information */
|
|
if(keyframe&1)
|
|
pkt->flags |= AV_PKT_FLAG_KEY;
|
|
|
|
return HEADER_SIZE + size;
|
|
}
|
|
|
|
AVInputFormat ff_msnwc_tcp_demuxer = {
|
|
.name = "msnwctcp",
|
|
.long_name = NULL_IF_CONFIG_SMALL("MSN TCP Webcam stream"),
|
|
.read_probe = msnwc_tcp_probe,
|
|
.read_header = msnwc_tcp_read_header,
|
|
.read_packet = msnwc_tcp_read_packet,
|
|
};
|