blob: 3c73ac7b2c634cf06131e3959c5369bbe09834ff
| 1 | /* |
| 2 | * Copyright (C) 2008 Ramiro Polla |
| 3 | * |
| 4 | * This file is part of FFmpeg. |
| 5 | * |
| 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. |
| 10 | * |
| 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. |
| 15 | * |
| 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 |
| 19 | */ |
| 20 | |
| 21 | #include "libavcodec/bytestream.h" |
| 22 | #include "avformat.h" |
| 23 | #include "internal.h" |
| 24 | |
| 25 | #define HEADER_SIZE 24 |
| 26 | |
| 27 | /* |
| 28 | * Header structure: |
| 29 | * uint16_t ss; // struct size |
| 30 | * uint16_t width; // frame width |
| 31 | * uint16_t height; // frame height |
| 32 | * uint16_t ff; // keyframe + some other info(???) |
| 33 | * uint32_t size; // size of data |
| 34 | * uint32_t fourcc; // ML20 |
| 35 | * uint32_t u3; // ? |
| 36 | * uint32_t ts; // time |
| 37 | */ |
| 38 | |
| 39 | static int msnwc_tcp_probe(AVProbeData *p) |
| 40 | { |
| 41 | int i; |
| 42 | |
| 43 | for (i = 0; i + HEADER_SIZE <= p->buf_size; i++) { |
| 44 | uint16_t width, height; |
| 45 | uint32_t fourcc; |
| 46 | const uint8_t *bytestream = p->buf + i; |
| 47 | |
| 48 | if (bytestream_get_le16(&bytestream) != HEADER_SIZE) |
| 49 | continue; |
| 50 | width = bytestream_get_le16(&bytestream); |
| 51 | height = bytestream_get_le16(&bytestream); |
| 52 | if (!(width == 320 && |
| 53 | height == 240) && !(width == 160 && height == 120)) |
| 54 | continue; |
| 55 | bytestream += 2; // keyframe |
| 56 | bytestream += 4; // size |
| 57 | fourcc = bytestream_get_le32(&bytestream); |
| 58 | if (fourcc != MKTAG('M', 'L', '2', '0')) |
| 59 | continue; |
| 60 | |
| 61 | if (i) { |
| 62 | if (i < 14) /* starts with SwitchBoard connection info */ |
| 63 | return AVPROBE_SCORE_MAX / 2; |
| 64 | else /* starts in the middle of stream */ |
| 65 | return AVPROBE_SCORE_MAX / 3; |
| 66 | } else { |
| 67 | return AVPROBE_SCORE_MAX; |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | return 0; |
| 72 | } |
| 73 | |
| 74 | static int msnwc_tcp_read_header(AVFormatContext *ctx) |
| 75 | { |
| 76 | AVIOContext *pb = ctx->pb; |
| 77 | AVCodecParameters *par; |
| 78 | AVStream *st; |
| 79 | |
| 80 | st = avformat_new_stream(ctx, NULL); |
| 81 | if (!st) |
| 82 | return AVERROR(ENOMEM); |
| 83 | |
| 84 | par = st->codecpar; |
| 85 | par->codec_type = AVMEDIA_TYPE_VIDEO; |
| 86 | par->codec_id = AV_CODEC_ID_MIMIC; |
| 87 | par->codec_tag = MKTAG('M', 'L', '2', '0'); |
| 88 | |
| 89 | avpriv_set_pts_info(st, 32, 1, 1000); |
| 90 | |
| 91 | /* Some files start with "connected\r\n\r\n". |
| 92 | * So skip until we find the first byte of struct size */ |
| 93 | while(avio_r8(pb) != HEADER_SIZE && !avio_feof(pb)) ; |
| 94 | |
| 95 | if(avio_feof(pb)) { |
| 96 | av_log(ctx, AV_LOG_ERROR, "Could not find valid start.\n"); |
| 97 | return AVERROR_INVALIDDATA; |
| 98 | } |
| 99 | |
| 100 | return 0; |
| 101 | } |
| 102 | |
| 103 | static int msnwc_tcp_read_packet(AVFormatContext *ctx, AVPacket *pkt) |
| 104 | { |
| 105 | AVIOContext *pb = ctx->pb; |
| 106 | uint16_t keyframe; |
| 107 | uint32_t size, timestamp; |
| 108 | int ret; |
| 109 | |
| 110 | avio_skip(pb, 1); /* one byte has been read ahead */ |
| 111 | avio_skip(pb, 2); |
| 112 | avio_skip(pb, 2); |
| 113 | keyframe = avio_rl16(pb); |
| 114 | size = avio_rl32(pb); |
| 115 | avio_skip(pb, 4); |
| 116 | avio_skip(pb, 4); |
| 117 | timestamp = avio_rl32(pb); |
| 118 | |
| 119 | if (!size) |
| 120 | return AVERROR_INVALIDDATA; |
| 121 | |
| 122 | if ((ret = av_get_packet(pb, pkt, size)) < 0) |
| 123 | return ret; |
| 124 | |
| 125 | avio_skip(pb, 1); /* Read ahead one byte of struct size like read_header */ |
| 126 | |
| 127 | pkt->pts = timestamp; |
| 128 | pkt->dts = timestamp; |
| 129 | pkt->stream_index = 0; |
| 130 | |
| 131 | /* Some aMsn generated videos (or was it Mercury Messenger?) don't set |
| 132 | * this bit and rely on the codec to get keyframe information */ |
| 133 | if (keyframe & 1) |
| 134 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 135 | |
| 136 | return HEADER_SIZE + size; |
| 137 | } |
| 138 | |
| 139 | AVInputFormat ff_msnwc_tcp_demuxer = { |
| 140 | .name = "msnwctcp", |
| 141 | .long_name = NULL_IF_CONFIG_SMALL("MSN TCP Webcam stream"), |
| 142 | .read_probe = msnwc_tcp_probe, |
| 143 | .read_header = msnwc_tcp_read_header, |
| 144 | .read_packet = msnwc_tcp_read_packet, |
| 145 | }; |
| 146 |