mirror of https://git.ffmpeg.org/ffmpeg.git
78 lines
2.4 KiB
C
78 lines
2.4 KiB
C
/*
|
|
* RAW DTS demuxer
|
|
* Copyright (c) 2008 Benjamin Larsson
|
|
*
|
|
* 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 "libavcodec/bytestream.h"
|
|
#include "avformat.h"
|
|
#include "rawdec.h"
|
|
|
|
#define DCA_MARKER_14B_BE 0x1FFFE800
|
|
#define DCA_MARKER_14B_LE 0xFF1F00E8
|
|
#define DCA_MARKER_RAW_BE 0x7FFE8001
|
|
#define DCA_MARKER_RAW_LE 0xFE7F0180
|
|
|
|
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_MARKER_RAW_BE || state == DCA_MARKER_RAW_LE)
|
|
markers[0]++;
|
|
|
|
/* 14 bits big-endian bitstream */
|
|
if (state == DCA_MARKER_14B_BE)
|
|
if ((bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
|
|
markers[1]++;
|
|
|
|
/* 14 bits little-endian bitstream */
|
|
if (state == DCA_MARKER_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_MAX/2+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,
|
|
};
|