1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
/*
* Copyright (c) 2016 Paul B Mahol
*
* 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 "bsf.h"
#include "bsf_internal.h"
#include "bytestream.h"
#include "dca_syncwords.h"
static int dca_core_filter(AVBSFContext *ctx, AVPacket *pkt)
{
GetByteContext gb;
uint32_t syncword;
int core_size = 0, ret;
ret = ff_bsf_get_packet_ref(ctx, pkt);
if (ret < 0)
return ret;
bytestream2_init(&gb, pkt->data, pkt->size);
syncword = bytestream2_get_be32(&gb);
bytestream2_skip(&gb, 1);
switch (syncword) {
case DCA_SYNCWORD_CORE_BE:
core_size = ((bytestream2_get_be24(&gb) >> 4) & 0x3fff) + 1;
break;
}
if (core_size > 0 && core_size <= pkt->size) {
pkt->size = core_size;
}
return 0;
}
static const enum AVCodecID codec_ids[] = {
AV_CODEC_ID_DTS, AV_CODEC_ID_NONE,
};
const FFBitStreamFilter ff_dca_core_bsf = {
.p.name = "dca_core",
.p.codec_ids = codec_ids,
.filter = dca_core_filter,
};
|
