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/*
* RAW DTS demuxer
* Copyright (c) 2008 Benjamin Larsson
*
* 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 "libavcodec/bytestream.h"
#include "libavcodec/dca_syncwords.h"
#include "avformat.h"
#include "rawdec.h"
static int dts_probe(AVProbeData *p)
{
const uint8_t *buf, *bufp;
uint32_t state = -1;
int markers[3] = {0};
int sum, max;
buf = p->buf;
for(; buf < (p->buf+p->buf_size)-2; buf+=2) {
bufp = buf;
state = (state << 16) | bytestream_get_be16(&bufp);
/* regular bitstream */
if (state == DCA_SYNCWORD_CORE_BE || state == DCA_SYNCWORD_CORE_LE)
markers[0]++;
/* 14 bits big-endian bitstream */
if (state == DCA_SYNCWORD_CORE_14B_BE)
if ((bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
markers[1]++;
/* 14 bits little-endian bitstream */
if (state == DCA_SYNCWORD_CORE_14B_LE)
if ((bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
markers[2]++;
}
sum = markers[0] + markers[1] + markers[2];
max = markers[1] > markers[0];
max = markers[2] > markers[max] ? 2 : max;
if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 &&
markers[max] * 4 > sum * 3)
return AVPROBE_SCORE_EXTENSION + 1;
return 0;
}
AVInputFormat ff_dts_demuxer = {
.name = "dts",
.long_name = NULL_IF_CONFIG_SMALL("raw DTS"),
.read_probe = dts_probe,
.read_header = ff_raw_audio_read_header,
.read_packet = ff_raw_read_partial_packet,
.flags = AVFMT_GENERIC_INDEX,
.extensions = "dts",
.raw_codec_id = AV_CODEC_ID_DTS,
};
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