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
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/*
* raw FLAC muxer
* Copyright (c) 2006-2009 Justin Ruggles
*
* 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/flac.h"
#include "avformat.h"
#include "flacenc.h"
#include "metadata.h"
#include "vorbiscomment.h"
#include "libavcodec/bytestream.h"
static int flac_write_block_padding(AVIOContext *pb, unsigned int n_padding_bytes,
int last_block)
{
avio_w8(pb, last_block ? 0x81 : 0x01);
avio_wb24(pb, n_padding_bytes);
while (n_padding_bytes > 0) {
avio_w8(pb, 0);
n_padding_bytes--;
}
return 0;
}
static int flac_write_block_comment(AVIOContext *pb, AVMetadata **m,
int last_block, int bitexact)
{
const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
unsigned int len, count;
uint8_t *p, *p0;
ff_metadata_conv(m, ff_vorbiscomment_metadata_conv, NULL);
len = ff_vorbiscomment_length(*m, vendor, &count);
p0 = av_malloc(len+4);
if (!p0)
return AVERROR(ENOMEM);
p = p0;
bytestream_put_byte(&p, last_block ? 0x84 : 0x04);
bytestream_put_be24(&p, len);
ff_vorbiscomment_write(&p, m, vendor, count);
avio_write(pb, p0, len+4);
av_freep(&p0);
p = NULL;
return 0;
}
static int flac_write_header(struct AVFormatContext *s)
{
int ret;
AVCodecContext *codec = s->streams[0]->codec;
ret = ff_flac_write_header(s->pb, codec, 0);
if (ret)
return ret;
ret = flac_write_block_comment(s->pb, &s->metadata, 0,
codec->flags & CODEC_FLAG_BITEXACT);
if (ret)
return ret;
/* The command line flac encoder defaults to placing a seekpoint
* every 10s. So one might add padding to allow that later
* but there seems to be no simple way to get the duration here.
* So let's try the flac default of 8192 bytes */
flac_write_block_padding(s->pb, 8192, 1);
return ret;
}
static int flac_write_trailer(struct AVFormatContext *s)
{
AVIOContext *pb = s->pb;
uint8_t *streaminfo;
enum FLACExtradataFormat format;
int64_t file_size;
if (!ff_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo))
return -1;
if (!url_is_streamed(pb)) {
/* rewrite the STREAMINFO header block data */
file_size = avio_tell(pb);
avio_seek(pb, 8, SEEK_SET);
avio_write(pb, streaminfo, FLAC_STREAMINFO_SIZE);
avio_seek(pb, file_size, SEEK_SET);
put_flush_packet(pb);
} else {
av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n");
}
return 0;
}
static int flac_write_packet(struct AVFormatContext *s, AVPacket *pkt)
{
avio_write(s->pb, pkt->data, pkt->size);
put_flush_packet(s->pb);
return 0;
}
AVOutputFormat ff_flac_muxer = {
"flac",
NULL_IF_CONFIG_SMALL("raw FLAC"),
"audio/x-flac",
"flac",
0,
CODEC_ID_FLAC,
CODEC_ID_NONE,
flac_write_header,
flac_write_packet,
flac_write_trailer,
.flags= AVFMT_NOTIMESTAMPS,
};
|
