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/*
* Brute Force & Ignorance (BFI) demuxer
* Copyright (c) 2008 Sisir Koppaka
*
* 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
*/
/**
* @file
* @brief Brute Force & Ignorance (.bfi) file demuxer
* @author Sisir Koppaka ( sisir.koppaka at gmail dot com )
* @see http://wiki.multimedia.cx/index.php?title=BFI
*/
#include "libavutil/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
typedef struct BFIContext {
int nframes;
int audio_frame;
int video_frame;
int video_size;
int avflag;
} BFIContext;
static int bfi_probe(AVProbeData * p)
{
/* Check file header */
if (AV_RL32(p->buf) == MKTAG('B', 'F', '&', 'I'))
return AVPROBE_SCORE_MAX;
else
return 0;
}
static int bfi_read_header(AVFormatContext * s)
{
BFIContext *bfi = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *vstream;
AVStream *astream;
int fps, chunk_header;
/* Initialize the video codec... */
vstream = avformat_new_stream(s, NULL);
if (!vstream)
return AVERROR(ENOMEM);
/* Initialize the audio codec... */
astream = avformat_new_stream(s, NULL);
if (!astream)
return AVERROR(ENOMEM);
/* Set the total number of frames. */
avio_skip(pb, 8);
chunk_header = avio_rl32(pb);
bfi->nframes = avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
avio_rl32(pb);
fps = avio_rl32(pb);
avio_skip(pb, 12);
vstream->codecpar->width = avio_rl32(pb);
vstream->codecpar->height = avio_rl32(pb);
/*Load the palette to extradata */
avio_skip(pb, 8);
vstream->codecpar->extradata = av_malloc(768);
vstream->codecpar->extradata_size = 768;
avio_read(pb, vstream->codecpar->extradata,
vstream->codecpar->extradata_size);
astream->codecpar->sample_rate = avio_rl32(pb);
/* Set up the video codec... */
avpriv_set_pts_info(vstream, 32, 1, fps);
vstream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
vstream->codecpar->codec_id = AV_CODEC_ID_BFI;
vstream->codecpar->format = AV_PIX_FMT_PAL8;
/* Set up the audio codec now... */
astream->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
astream->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
astream->codecpar->channels = 1;
astream->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
astream->codecpar->bits_per_coded_sample = 8;
astream->codecpar->bit_rate =
astream->codecpar->sample_rate * astream->codecpar->bits_per_coded_sample;
avio_seek(pb, chunk_header - 3, SEEK_SET);
avpriv_set_pts_info(astream, 64, 1, astream->codecpar->sample_rate);
return 0;
}
static int bfi_read_packet(AVFormatContext * s, AVPacket * pkt)
{
BFIContext *bfi = s->priv_data;
AVIOContext *pb = s->pb;
int ret, audio_offset, video_offset, chunk_size, audio_size = 0;
if (bfi->nframes == 0 || pb->eof_reached) {
return AVERROR(EIO);
}
/* If all previous chunks were completely read, then find a new one... */
if (!bfi->avflag) {
uint32_t state = 0;
while(state != MKTAG('S','A','V','I')){
if (pb->eof_reached)
return AVERROR(EIO);
state = 256*state + avio_r8(pb);
}
/* Now that the chunk's location is confirmed, we proceed... */
chunk_size = avio_rl32(pb);
avio_rl32(pb);
audio_offset = avio_rl32(pb);
avio_rl32(pb);
video_offset = avio_rl32(pb);
audio_size = video_offset - audio_offset;
bfi->video_size = chunk_size - video_offset;
if (audio_size < 0 || bfi->video_size < 0) {
av_log(s, AV_LOG_ERROR, "Invalid audio/video offsets or chunk size\n");
return AVERROR_INVALIDDATA;
}
//Tossing an audio packet at the audio decoder.
ret = av_get_packet(pb, pkt, audio_size);
if (ret < 0)
return ret;
pkt->pts = bfi->audio_frame;
bfi->audio_frame += ret;
} else if (bfi->video_size > 0) {
//Tossing a video packet at the video decoder.
ret = av_get_packet(pb, pkt, bfi->video_size);
if (ret < 0)
return ret;
pkt->pts = bfi->video_frame;
bfi->video_frame += ret / bfi->video_size;
/* One less frame to read. A cursory decrement. */
bfi->nframes--;
} else {
/* Empty video packet */
ret = AVERROR(EAGAIN);
}
bfi->avflag = !bfi->avflag;
pkt->stream_index = bfi->avflag;
return ret;
}
AVInputFormat ff_bfi_demuxer = {
.name = "bfi",
.long_name = NULL_IF_CONFIG_SMALL("Brute Force & Ignorance"),
.priv_data_size = sizeof(BFIContext),
.read_probe = bfi_probe,
.read_header = bfi_read_header,
.read_packet = bfi_read_packet,
};
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