ffmpeg/libavformat/mlpdec.c

86 lines
2.6 KiB
C

/*
* MLP and TrueHD demuxer
* Copyright (c) 2001 Fabrice Bellard
* Copyright (c) 2005 Alex Beregszaszi
* Copyright (c) 2015 Carl Eugen Hoyos
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "rawdec.h"
#include "libavutil/intreadwrite.h"
static int av_always_inline mlp_thd_probe(AVProbeData *p, uint32_t sync)
{
const uint8_t *buf, *last_buf = p->buf, *end = p->buf + p->buf_size;
int frames = 0, valid = 0, size = 0;
for (buf = p->buf; buf + 8 <= end; buf++) {
if (AV_RB32(buf + 4) == sync) {
frames++;
if (last_buf + size == buf) {
valid++;
}
last_buf = buf;
size = (AV_RB16(buf) & 0xfff) * 2;
} else if (buf - last_buf == size) {
size += (AV_RB16(buf) & 0xfff) * 2;
}
}
if (valid >= 100)
return AVPROBE_SCORE_MAX;
return 0;
}
#if CONFIG_MLP_DEMUXER
static int mlp_probe(AVProbeData *p)
{
return mlp_thd_probe(p, 0xf8726fbb);
}
AVInputFormat ff_mlp_demuxer = {
.name = "mlp",
.long_name = NULL_IF_CONFIG_SMALL("raw MLP"),
.read_probe = mlp_probe,
.read_header = ff_raw_audio_read_header,
.read_packet = ff_raw_read_partial_packet,
.flags = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
.extensions = "mlp",
.raw_codec_id = AV_CODEC_ID_MLP,
};
#endif
#if CONFIG_TRUEHD_DEMUXER
static int thd_probe(AVProbeData *p)
{
return mlp_thd_probe(p, 0xf8726fba);
}
AVInputFormat ff_truehd_demuxer = {
.name = "truehd",
.long_name = NULL_IF_CONFIG_SMALL("raw TrueHD"),
.read_probe = thd_probe,
.read_header = ff_raw_audio_read_header,
.read_packet = ff_raw_read_partial_packet,
.flags = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
.extensions = "thd",
.raw_codec_id = AV_CODEC_ID_TRUEHD,
};
#endif