yading@11: /*
yading@11:  * Adobe Filmstrip demuxer
yading@11:  * Copyright (c) 2010 Peter Ross
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * Adobe Filmstrip demuxer
yading@11:  */
yading@11: 
yading@11: #include "libavutil/intreadwrite.h"
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: 
yading@11: #define RAND_TAG MKBETAG('R','a','n','d')
yading@11: 
yading@11: typedef struct {
yading@11:     int leading;
yading@11: } FilmstripDemuxContext;
yading@11: 
yading@11: static int read_header(AVFormatContext *s)
yading@11: {
yading@11:     FilmstripDemuxContext *film = s->priv_data;
yading@11:     AVIOContext *pb = s->pb;
yading@11:     AVStream *st;
yading@11: 
yading@11:     if (!s->pb->seekable)
yading@11:         return AVERROR(EIO);
yading@11: 
yading@11:     avio_seek(pb, avio_size(pb) - 36, SEEK_SET);
yading@11:     if (avio_rb32(pb) != RAND_TAG) {
yading@11:         av_log(s, AV_LOG_ERROR, "magic number not found\n");
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     }
yading@11: 
yading@11:     st = avformat_new_stream(s, NULL);
yading@11:     if (!st)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     st->nb_frames = avio_rb32(pb);
yading@11:     if (avio_rb16(pb) != 0) {
yading@11:         avpriv_request_sample(s, "Unsupported packing method");
yading@11:         return AVERROR_PATCHWELCOME;
yading@11:     }
yading@11: 
yading@11:     avio_skip(pb, 2);
yading@11:     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
yading@11:     st->codec->codec_id   = AV_CODEC_ID_RAWVIDEO;
yading@11:     st->codec->pix_fmt    = AV_PIX_FMT_RGBA;
yading@11:     st->codec->codec_tag  = 0; /* no fourcc */
yading@11:     st->codec->width      = avio_rb16(pb);
yading@11:     st->codec->height     = avio_rb16(pb);
yading@11:     film->leading         = avio_rb16(pb);
yading@11:     avpriv_set_pts_info(st, 64, 1, avio_rb16(pb));
yading@11: 
yading@11:     avio_seek(pb, 0, SEEK_SET);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int read_packet(AVFormatContext *s,
yading@11:                        AVPacket *pkt)
yading@11: {
yading@11:     FilmstripDemuxContext *film = s->priv_data;
yading@11:     AVStream *st = s->streams[0];
yading@11: 
yading@11:     if (url_feof(s->pb))
yading@11:         return AVERROR(EIO);
yading@11:     pkt->dts = avio_tell(s->pb) / (st->codec->width * (st->codec->height + film->leading) * 4);
yading@11:     pkt->size = av_get_packet(s->pb, pkt, st->codec->width * st->codec->height * 4);
yading@11:     avio_skip(s->pb, st->codec->width * film->leading * 4);
yading@11:     if (pkt->size < 0)
yading@11:         return pkt->size;
yading@11:     pkt->flags |= AV_PKT_FLAG_KEY;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
yading@11: {
yading@11:     AVStream *st = s->streams[stream_index];
yading@11:     if (avio_seek(s->pb, FFMAX(timestamp, 0) * st->codec->width * st->codec->height * 4, SEEK_SET) < 0)
yading@11:         return -1;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_filmstrip_demuxer = {
yading@11:     .name           = "filmstrip",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("Adobe Filmstrip"),
yading@11:     .priv_data_size = sizeof(FilmstripDemuxContext),
yading@11:     .read_header    = read_header,
yading@11:     .read_packet    = read_packet,
yading@11:     .read_seek      = read_seek,
yading@11:     .extensions     = "flm",
yading@11: };