| 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 "avformat.h" |
| 29 | #include "internal.h" |
| 30 | |
| 31 | #define RAND_TAG MKBETAG('R','a','n','d') |
| 32 | |
| 33 | typedef struct { |
| 34 | int leading; |
| 35 | } FilmstripDemuxContext; |
| 36 | |
| 37 | static int read_header(AVFormatContext *s) |
| 38 | { |
| 39 | FilmstripDemuxContext *film = s->priv_data; |
| 40 | AVIOContext *pb = s->pb; |
| 41 | AVStream *st; |
| 42 | |
| 43 | if (!s->pb->seekable) |
| 44 | return AVERROR(EIO); |
| 45 | |
| 46 | avio_seek(pb, avio_size(pb) - 36, SEEK_SET); |
| 47 | if (avio_rb32(pb) != RAND_TAG) { |
| 48 | av_log(s, AV_LOG_ERROR, "magic number not found\n"); |
| 49 | return AVERROR_INVALIDDATA; |
| 50 | } |
| 51 | |
| 52 | st = avformat_new_stream(s, NULL); |
| 53 | if (!st) |
| 54 | return AVERROR(ENOMEM); |
| 55 | |
| 56 | st->nb_frames = avio_rb32(pb); |
| 57 | if (avio_rb16(pb) != 0) { |
| 58 | avpriv_request_sample(s, "Unsupported packing method"); |
| 59 | return AVERROR_PATCHWELCOME; |
| 60 | } |
| 61 | |
| 62 | avio_skip(pb, 2); |
| 63 | st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| 64 | st->codec->codec_id = AV_CODEC_ID_RAWVIDEO; |
| 65 | st->codec->pix_fmt = AV_PIX_FMT_RGBA; |
| 66 | st->codec->codec_tag = 0; /* no fourcc */ |
| 67 | st->codec->width = avio_rb16(pb); |
| 68 | st->codec->height = avio_rb16(pb); |
| 69 | film->leading = avio_rb16(pb); |
| 70 | avpriv_set_pts_info(st, 64, 1, avio_rb16(pb)); |
| 71 | |
| 72 | avio_seek(pb, 0, SEEK_SET); |
| 73 | |
| 74 | return 0; |
| 75 | } |
| 76 | |
| 77 | static int read_packet(AVFormatContext *s, |
| 78 | AVPacket *pkt) |
| 79 | { |
| 80 | FilmstripDemuxContext *film = s->priv_data; |
| 81 | AVStream *st = s->streams[0]; |
| 82 | |
| 83 | if (avio_feof(s->pb)) |
| 84 | return AVERROR(EIO); |
| 85 | pkt->dts = avio_tell(s->pb) / (st->codec->width * (st->codec->height + film->leading) * 4); |
| 86 | pkt->size = av_get_packet(s->pb, pkt, st->codec->width * st->codec->height * 4); |
| 87 | avio_skip(s->pb, st->codec->width * film->leading * 4); |
| 88 | if (pkt->size < 0) |
| 89 | return pkt->size; |
| 90 | pkt->flags |= AV_PKT_FLAG_KEY; |
| 91 | return 0; |
| 92 | } |
| 93 | |
| 94 | static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) |
| 95 | { |
| 96 | AVStream *st = s->streams[stream_index]; |
| 97 | if (avio_seek(s->pb, FFMAX(timestamp, 0) * st->codec->width * st->codec->height * 4, SEEK_SET) < 0) |
| 98 | return -1; |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | AVInputFormat ff_filmstrip_demuxer = { |
| 103 | .name = "filmstrip", |
| 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, |
| 109 | .extensions = "flm", |
| 110 | }; |