2 * Copyright (C) 2008 Ramiro Polla <ramiro@lisha.ufsc.br>
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "libavcodec/bytestream.h"
24 #define HEADER_SIZE 24
28 * uint16_t ss; // struct size
29 * uint16_t width; // frame width
30 * uint16_t height; // frame height
31 * uint16_t ff; // keyframe + some other info(???)
32 * uint32_t size; // size of data
33 * uint32_t fourcc; // ML20
35 * uint32_t ts; // time
38 static int msnwc_tcp_probe(AVProbeData *p)
42 for(i = 0 ; i + HEADER_SIZE <= p->buf_size ; i++) {
43 uint16_t width, height;
45 const uint8_t *bytestream = p->buf+i;
47 if(bytestream_get_le16(&bytestream) != HEADER_SIZE)
49 width = bytestream_get_le16(&bytestream);
50 height = bytestream_get_le16(&bytestream);
51 if(!(width==320 && height==240) && !(width==160 && height==120))
53 bytestream += 2; // keyframe
54 bytestream += 4; // size
55 fourcc = bytestream_get_le32(&bytestream);
56 if(fourcc != MKTAG('M', 'L', '2', '0'))
60 if(i < 14) /* starts with SwitchBoard connection info */
61 return AVPROBE_SCORE_MAX / 2;
62 else /* starts in the middle of stream */
63 return AVPROBE_SCORE_MAX / 3;
65 return AVPROBE_SCORE_MAX;
72 static int msnwc_tcp_read_header(AVFormatContext *ctx, AVFormatParameters *ap)
74 ByteIOContext *pb = ctx->pb;
75 AVCodecContext *codec;
78 st = av_new_stream(ctx, 0);
80 return AVERROR(ENOMEM);
83 codec->codec_type = AVMEDIA_TYPE_VIDEO;
84 codec->codec_id = CODEC_ID_MIMIC;
85 codec->codec_tag = MKTAG('M', 'L', '2', '0');
87 av_set_pts_info(st, 32, 1, 1000);
89 /* Some files start with "connected\r\n\r\n".
90 * So skip until we find the first byte of struct size */
91 while(get_byte(pb) != HEADER_SIZE && !url_feof(pb));
94 av_log(ctx, AV_LOG_ERROR, "Could not find valid start.");
101 static int msnwc_tcp_read_packet(AVFormatContext *ctx, AVPacket *pkt)
103 ByteIOContext *pb = ctx->pb;
105 uint32_t size, timestamp;
107 url_fskip(pb, 1); /* one byte has been read ahead */
110 keyframe = get_le16(pb);
114 timestamp = get_le32(pb);
116 if(!size || av_get_packet(pb, pkt, size) != size)
119 url_fskip(pb, 1); /* Read ahead one byte of struct size like read_header */
121 pkt->pts = timestamp;
122 pkt->dts = timestamp;
123 pkt->stream_index = 0;
125 /* Some aMsn generated videos (or was it Mercury Messenger?) don't set
126 * this bit and rely on the codec to get keyframe information */
128 pkt->flags |= AV_PKT_FLAG_KEY;
130 return HEADER_SIZE + size;
133 AVInputFormat ff_msnwc_tcp_demuxer = {
135 NULL_IF_CONFIG_SMALL("MSN TCP Webcam stream"),
138 msnwc_tcp_read_header,
139 msnwc_tcp_read_packet,