From eaf5d0112bcaecd81016373259bad40a38608e62 Mon Sep 17 00:00:00 2001 From: Nicolas Martin Date: Sun, 8 Feb 2009 18:50:32 +0000 Subject: NC camera demuxer Patch by Nicolas Martin - elvadrias at gmail Originally committed as revision 17062 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/ncdec.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 libavformat/ncdec.c (limited to 'libavformat/ncdec.c') diff --git a/libavformat/ncdec.c b/libavformat/ncdec.c new file mode 100644 index 0000000000..e6cca1068b --- /dev/null +++ b/libavformat/ncdec.c @@ -0,0 +1,100 @@ +/* + * NC camera feed demuxer + * Copyright (c) 2009 Nicolas Martin (martinic at iro dot umontreal dot ca) + * Edouard Auvinet + * + * 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 "libavutil/intreadwrite.h" +#include "avformat.h" + +#define NC_VIDEO_FLAG 0x1A5 + +static int nc_probe(AVProbeData *probe_packet) +{ + int size; + + if (AV_RB32(probe_packet->buf) != NC_VIDEO_FLAG) + return 0; + + size = AV_RL16(probe_packet->buf + 5); + + if (size + 20 > probe_packet->buf_size) + return 3*AVPROBE_SCORE_MAX/2; + + if (AV_RB32(probe_packet->buf+16+size) == NC_VIDEO_FLAG) + return AVPROBE_SCORE_MAX; + + return 0; +} + +static int nc_read_header(AVFormatContext *s, AVFormatParameters *ap) +{ + AVStream *st = av_new_stream(s, 0); + + if (!st) + return AVERROR(ENOMEM); + + st->codec->codec_type = CODEC_TYPE_VIDEO; + st->codec->codec_id = CODEC_ID_MPEG4; + st->need_parsing = AVSTREAM_PARSE_FULL; + + av_set_pts_info(st, 64, 1, 100); + + return 0; +} + +static int nc_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + int size; + + uint32_t state=-1; + while (state != NC_VIDEO_FLAG) { + if (url_feof(s->pb)) + return AVERROR(EIO); + state = (state<<8) + get_byte(s->pb); + } + + get_byte(s->pb); + size = get_le16(s->pb); + url_fskip(s->pb, 9); + + if (size == 0) { + av_log(s, AV_LOG_DEBUG, "Next packet size is zero\n"); + return AVERROR(EAGAIN); + } + + int ret = av_get_packet(s->pb, pkt, size); + if (ret != size) { + if (ret > 0) av_free_packet(pkt); + return AVERROR(EIO); + } + + pkt->stream_index = 0; + return size; +} + +AVInputFormat nc_demuxer = { + "nc", + NULL_IF_CONFIG_SMALL("NC camera feed format"), + 0, + nc_probe, + nc_read_header, + nc_read_packet, + .extensions = "v", +}; -- cgit v1.2.3