ffmpeg/libavformat/dtsdec.c

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/*
* 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 "libavcodec/dca.h"
#include "libavcodec/dca_syncwords.h"
#include "libavcodec/get_bits.h"
#include "avformat.h"
#include "rawdec.h"
static int dts_probe(AVProbeData *p)
{
const uint8_t *buf, *bufp;
uint32_t state = -1;
int markers[4*16] = {0};
int sum, max, i;
int64_t diff = 0;
Merge commit '059a934806d61f7af9ab3fd9f74994b838ea5eba' * commit '059a934806d61f7af9ab3fd9f74994b838ea5eba': lavc: Consistently prefix input buffer defines Conflicts: doc/examples/decoding_encoding.c libavcodec/4xm.c libavcodec/aac_adtstoasc_bsf.c libavcodec/aacdec.c libavcodec/aacenc.c libavcodec/ac3dec.h libavcodec/asvenc.c libavcodec/avcodec.h libavcodec/avpacket.c libavcodec/dvdec.c libavcodec/ffv1enc.c libavcodec/g2meet.c libavcodec/gif.c libavcodec/h264.c libavcodec/h264_mp4toannexb_bsf.c libavcodec/huffyuvdec.c libavcodec/huffyuvenc.c libavcodec/jpeglsenc.c libavcodec/libxvid.c libavcodec/mdec.c libavcodec/motionpixels.c libavcodec/mpeg4videodec.c libavcodec/mpegvideo.c libavcodec/noise_bsf.c libavcodec/nuv.c libavcodec/nvenc.c libavcodec/options.c libavcodec/parser.c libavcodec/pngenc.c libavcodec/proresenc_kostya.c libavcodec/qsvdec.c libavcodec/svq1enc.c libavcodec/tiffenc.c libavcodec/truemotion2.c libavcodec/utils.c libavcodec/utvideoenc.c libavcodec/vc1dec.c libavcodec/wmalosslessdec.c libavformat/adxdec.c libavformat/aiffdec.c libavformat/apc.c libavformat/apetag.c libavformat/avidec.c libavformat/bink.c libavformat/cafdec.c libavformat/flvdec.c libavformat/id3v2.c libavformat/isom.c libavformat/matroskadec.c libavformat/mov.c libavformat/mpc.c libavformat/mpc8.c libavformat/mpegts.c libavformat/mvi.c libavformat/mxfdec.c libavformat/mxg.c libavformat/nutdec.c libavformat/oggdec.c libavformat/oggparsecelt.c libavformat/oggparseflac.c libavformat/oggparseopus.c libavformat/oggparsespeex.c libavformat/omadec.c libavformat/rawdec.c libavformat/riffdec.c libavformat/rl2.c libavformat/rmdec.c libavformat/rtpdec_latm.c libavformat/rtpdec_mpeg4.c libavformat/rtpdec_qdm2.c libavformat/rtpdec_svq3.c libavformat/sierravmd.c libavformat/smacker.c libavformat/smush.c libavformat/spdifenc.c libavformat/takdec.c libavformat/tta.c libavformat/utils.c libavformat/vqf.c libavformat/westwood_vqa.c libavformat/xmv.c libavformat/xwma.c libavformat/yop.c Merged-by: Michael Niedermayer <michael@niedermayer.cc>
2015-07-27 20:53:16 +00:00
uint8_t hdr[12 + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 };
buf = p->buf + FFMIN(4096, p->buf_size);
for(; buf < (p->buf+p->buf_size)-2; buf+=2) {
int marker, sample_blocks, sample_rate, sr_code, framesize;
int lfe;
GetBitContext gb;
bufp = buf;
state = (state << 16) | bytestream_get_be16(&bufp);
if (buf - p->buf >= 4)
diff += FFABS(((int16_t)AV_RL16(buf)) - (int16_t)AV_RL16(buf-4));
/* regular bitstream */
if (state == DCA_SYNCWORD_CORE_BE &&
(bytestream_get_be16(&bufp) & 0xFC00) == 0xFC00)
marker = 0;
else if (state == DCA_SYNCWORD_CORE_LE &&
(bytestream_get_be16(&bufp) & 0x00FC) == 0x00FC)
marker = 1;
/* 14 bits big-endian bitstream */
else if (state == DCA_SYNCWORD_CORE_14B_BE &&
(bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0)
marker = 2;
/* 14 bits little-endian bitstream */
else if (state == DCA_SYNCWORD_CORE_14B_LE &&
(bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007)
marker = 3;
else
continue;
if (avpriv_dca_convert_bitstream(buf-2, 12, hdr, 12) < 0)
continue;
init_get_bits(&gb, hdr, 96);
skip_bits_long(&gb, 39);
sample_blocks = get_bits(&gb, 7) + 1;
if (sample_blocks < 8)
continue;
framesize = get_bits(&gb, 14) + 1;
if (framesize < 95)
continue;
skip_bits(&gb, 6);
sr_code = get_bits(&gb, 4);
sample_rate = avpriv_dca_sample_rates[sr_code];
if (sample_rate == 0)
continue;
get_bits(&gb, 5);
if (get_bits(&gb, 1))
continue;
skip_bits_long(&gb, 9);
lfe = get_bits(&gb, 2);
if (lfe > 2)
continue;
marker += 4* sr_code;
markers[marker] ++;
}
sum = max = 0;
for (i=0; i<FF_ARRAY_ELEMS(markers); i++) {
sum += markers[i];
if (markers[max] < markers[i])
max = i;
}
if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 &&
markers[max] * 4 > sum * 3 &&
diff / p->buf_size > 200)
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,
};