2 * Adobe Filmstrip demuxer
3 * Copyright (c) 2010 Peter Ross
5 * This file is part of Libav.
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.
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.
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
24 * Adobe Filmstrip demuxer
27 #include "libavutil/intreadwrite.h"
31 #define RAND_TAG MKBETAG('R','a','n','d')
35 } FilmstripDemuxContext;
37 static int read_header(AVFormatContext *s,
38 AVFormatParameters *ap)
40 FilmstripDemuxContext *film = s->priv_data;
41 AVIOContext *pb = s->pb;
47 avio_seek(pb, avio_size(pb) - 36, SEEK_SET);
48 if (avio_rb32(pb) != RAND_TAG) {
49 av_log(s, AV_LOG_ERROR, "magic number not found");
50 return AVERROR_INVALIDDATA;
53 st = avformat_new_stream(s, NULL);
55 return AVERROR(ENOMEM);
57 st->nb_frames = avio_rb32(pb);
58 if (avio_rb16(pb) != 0) {
59 av_log_ask_for_sample(s, "unsupported packing method\n");
60 return AVERROR_INVALIDDATA;
64 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
65 st->codec->codec_id = CODEC_ID_RAWVIDEO;
66 st->codec->pix_fmt = PIX_FMT_RGBA;
67 st->codec->codec_tag = 0; /* no fourcc */
68 st->codec->width = avio_rb16(pb);
69 st->codec->height = avio_rb16(pb);
70 film->leading = avio_rb16(pb);
71 avpriv_set_pts_info(st, 64, 1, avio_rb16(pb));
73 avio_seek(pb, 0, SEEK_SET);
78 static int read_packet(AVFormatContext *s,
81 FilmstripDemuxContext *film = s->priv_data;
82 AVStream *st = s->streams[0];
84 if (s->pb->eof_reached)
86 pkt->dts = avio_tell(s->pb) / (st->codec->width * (st->codec->height + film->leading) * 4);
87 pkt->size = av_get_packet(s->pb, pkt, st->codec->width * st->codec->height * 4);
88 avio_skip(s->pb, st->codec->width * film->leading * 4);
91 pkt->flags |= AV_PKT_FLAG_KEY;
95 static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
97 AVStream *st = s->streams[stream_index];
98 avio_seek(s->pb, FFMAX(timestamp, 0) * st->codec->width * st->codec->height * 4, SEEK_SET);
102 AVInputFormat ff_filmstrip_demuxer = {
104 .long_name = NULL_IF_CONFIG_SMALL("Adobe Filmstrip"),
105 .priv_data_size = sizeof(FilmstripDemuxContext),
106 .read_header = read_header,
107 .read_packet = read_packet,
108 .read_seek = read_seek,