ffmpeg/libavformat/mvi.c

135 lines
4.4 KiB
C

/*
* Motion Pixels MVI Demuxer
* Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#define MVI_FRAC_BITS 10
#define MVI_AUDIO_STREAM_INDEX 0
#define MVI_VIDEO_STREAM_INDEX 1
typedef struct MviDemuxContext {
unsigned int (*get_int)(AVIOContext *);
uint32_t audio_data_size;
uint64_t audio_size_counter;
uint64_t audio_frame_size;
int audio_size_left;
int video_frame_size;
} MviDemuxContext;
static int read_header(AVFormatContext *s, AVFormatParameters *ap)
{
MviDemuxContext *mvi = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *ast, *vst;
unsigned int version, frames_count, msecs_per_frame, player_version;
ast = av_new_stream(s, 0);
if (!ast)
return AVERROR(ENOMEM);
vst = av_new_stream(s, 0);
if (!vst)
return AVERROR(ENOMEM);
vst->codec->extradata_size = 2;
vst->codec->extradata = av_mallocz(2 + FF_INPUT_BUFFER_PADDING_SIZE);
version = avio_r8(pb);
vst->codec->extradata[0] = avio_r8(pb);
vst->codec->extradata[1] = avio_r8(pb);
frames_count = avio_rl32(pb);
msecs_per_frame = avio_rl32(pb);
vst->codec->width = avio_rl16(pb);
vst->codec->height = avio_rl16(pb);
avio_r8(pb);
ast->codec->sample_rate = avio_rl16(pb);
mvi->audio_data_size = avio_rl32(pb);
avio_r8(pb);
player_version = avio_rl32(pb);
avio_rl16(pb);
avio_r8(pb);
if (frames_count == 0 || mvi->audio_data_size == 0)
return AVERROR_INVALIDDATA;
if (version != 7 || player_version > 213) {
av_log(s, AV_LOG_ERROR, "unhandled version (%d,%d)\n", version, player_version);
return AVERROR_INVALIDDATA;
}
av_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codec->codec_id = CODEC_ID_PCM_U8;
ast->codec->channels = 1;
ast->codec->bits_per_coded_sample = 8;
ast->codec->bit_rate = ast->codec->sample_rate * 8;
av_set_pts_info(vst, 64, msecs_per_frame, 1000000);
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->codec_id = CODEC_ID_MOTIONPIXELS;
mvi->get_int = (vst->codec->width * vst->codec->height < (1 << 16)) ? avio_rl16 : avio_rl24;
mvi->audio_frame_size = ((uint64_t)mvi->audio_data_size << MVI_FRAC_BITS) / frames_count;
mvi->audio_size_counter = (ast->codec->sample_rate * 830 / mvi->audio_frame_size - 1) * mvi->audio_frame_size;
mvi->audio_size_left = mvi->audio_data_size;
return 0;
}
static int read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret, count;
MviDemuxContext *mvi = s->priv_data;
AVIOContext *pb = s->pb;
if (mvi->video_frame_size == 0) {
mvi->video_frame_size = (mvi->get_int)(pb);
if (mvi->audio_size_left == 0)
return AVERROR(EIO);
count = (mvi->audio_size_counter + mvi->audio_frame_size + 512) >> MVI_FRAC_BITS;
if (count > mvi->audio_size_left)
count = mvi->audio_size_left;
if ((ret = av_get_packet(pb, pkt, count)) < 0)
return ret;
pkt->stream_index = MVI_AUDIO_STREAM_INDEX;
mvi->audio_size_left -= count;
mvi->audio_size_counter += mvi->audio_frame_size - (count << MVI_FRAC_BITS);
} else {
if ((ret = av_get_packet(pb, pkt, mvi->video_frame_size)) < 0)
return ret;
pkt->stream_index = MVI_VIDEO_STREAM_INDEX;
mvi->video_frame_size = 0;
}
return 0;
}
AVInputFormat ff_mvi_demuxer = {
"mvi",
NULL_IF_CONFIG_SMALL("Motion Pixels MVI format"),
sizeof(MviDemuxContext),
NULL,
read_header,
read_packet,
.extensions = "mvi"
};