libavformat/ingenientdec.c

   1 /*
   2  * RAW Ingenient MJPEG demuxer
   3  * Copyright (c) 2005 Alex Beregszaszi
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "avformat.h"
  23 #include "rawdec.h"
  24
  25 // http://www.artificis.hu/files/texts/ingenient.txt
  26 static int ingenient_read_packet(AVFormatContext *s, AVPacket *pkt)
  27 {
  28     int ret, size, w, h, unk1, unk2;
  29
  30     if (avio_rl32(s->pb) != MKTAG('M', 'J', 'P', 'G'))
  31         return AVERROR(EIO); // FIXME
  32
  33     size = avio_rl32(s->pb);
  34
  35     w = avio_rl16(s->pb);
  36     h = avio_rl16(s->pb);
  37
  38     avio_skip(s->pb, 8); // zero + size (padded?)
  39     avio_skip(s->pb, 2);
  40     unk1 = avio_rl16(s->pb);
  41     unk2 = avio_rl16(s->pb);
  42     avio_skip(s->pb, 22); // ASCII timestamp
  43
  44     av_log(s, AV_LOG_DEBUG, "Ingenient packet: size=%d, width=%d, height=%d, unk1=%d unk2=%d\n",
  45         size, w, h, unk1, unk2);
  46
  47     if (av_new_packet(pkt, size) < 0)
  48         return AVERROR(ENOMEM);
  49
  50     pkt->pos = avio_tell(s->pb);
  51     pkt->stream_index = 0;
  52     ret = avio_read(s->pb, pkt->data, size);
  53     if (ret < 0) {
  54         av_free_packet(pkt);
  55         return ret;
  56     }
  57     pkt->size = ret;
  58     return ret;
  59 }
  60
  61 FF_RAWVIDEO_DEMUXER_CLASS(ingenient)
  62
  63 AVInputFormat ff_ingenient_demuxer = {
  64     .name           = "ingenient",
  65     .long_name      = NULL_IF_CONFIG_SMALL("raw Ingenient MJPEG"),
  66     .priv_data_size = sizeof(FFRawVideoDemuxerContext),
  67     .read_header    = ff_raw_video_read_header,
  68     .read_packet    = ingenient_read_packet,
  69     .flags          = AVFMT_GENERIC_INDEX,
  70     .extensions     = "cgi", // FIXME
  71     .raw_codec_id   = AV_CODEC_ID_MJPEG,
  72     .priv_class     = &ingenient_demuxer_class,
  73 };