1 /*
2 * Adobe Filmstrip demuxer
3 * Copyright (c) 2010 Peter Ross
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * Adobe Filmstrip demuxer
25 */
26
27 #include "libavutil/intreadwrite.h"
28 #include "libavutil/imgutils.h"
29 #include "avformat.h"
30 #include "internal.h"
31
32 #define RAND_TAG MKBETAG('R','a','n','d')
33
34 typedef struct FilmstripDemuxContext {
35 int leading;
36 } FilmstripDemuxContext;
37
read_header(AVFormatContext * s)38 static int read_header(AVFormatContext *s)
39 {
40 FilmstripDemuxContext *film = s->priv_data;
41 AVIOContext *pb = s->pb;
42 AVStream *st;
43
44 if (!(s->pb->seekable & AVIO_SEEKABLE_NORMAL))
45 return AVERROR(EIO);
46
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\n");
50 return AVERROR_INVALIDDATA;
51 }
52
53 st = avformat_new_stream(s, NULL);
54 if (!st)
55 return AVERROR(ENOMEM);
56
57 st->nb_frames = avio_rb32(pb);
58 if (avio_rb16(pb) != 0) {
59 avpriv_request_sample(s, "Unsupported packing method");
60 return AVERROR_PATCHWELCOME;
61 }
62
63 avio_skip(pb, 2);
64 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
65 st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
66 st->codecpar->format = AV_PIX_FMT_RGBA;
67 st->codecpar->codec_tag = 0; /* no fourcc */
68 st->codecpar->width = avio_rb16(pb);
69 st->codecpar->height = avio_rb16(pb);
70 film->leading = avio_rb16(pb);
71
72 if (av_image_check_size(st->codecpar->width, st->codecpar->height, 0, s) < 0)
73 return AVERROR_INVALIDDATA;
74
75 avpriv_set_pts_info(st, 64, 1, avio_rb16(pb));
76
77 avio_seek(pb, 0, SEEK_SET);
78
79 return 0;
80 }
81
read_packet(AVFormatContext * s,AVPacket * pkt)82 static int read_packet(AVFormatContext *s,
83 AVPacket *pkt)
84 {
85 FilmstripDemuxContext *film = s->priv_data;
86 AVStream *st = s->streams[0];
87
88 if (avio_feof(s->pb))
89 return AVERROR(EIO);
90 pkt->dts = avio_tell(s->pb) / (st->codecpar->width * (int64_t)(st->codecpar->height + film->leading) * 4);
91 pkt->size = av_get_packet(s->pb, pkt, st->codecpar->width * st->codecpar->height * 4);
92 avio_skip(s->pb, st->codecpar->width * (int64_t) film->leading * 4);
93 if (pkt->size < 0)
94 return pkt->size;
95 pkt->flags |= AV_PKT_FLAG_KEY;
96 return 0;
97 }
98
read_seek(AVFormatContext * s,int stream_index,int64_t timestamp,int flags)99 static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
100 {
101 AVStream *st = s->streams[stream_index];
102 if (avio_seek(s->pb, FFMAX(timestamp, 0) * st->codecpar->width * st->codecpar->height * 4, SEEK_SET) < 0)
103 return -1;
104 return 0;
105 }
106
107 AVInputFormat ff_filmstrip_demuxer = {
108 .name = "filmstrip",
109 .long_name = NULL_IF_CONFIG_SMALL("Adobe Filmstrip"),
110 .priv_data_size = sizeof(FilmstripDemuxContext),
111 .read_header = read_header,
112 .read_packet = read_packet,
113 .read_seek = read_seek,
114 .extensions = "flm",
115 };
116