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/*
* 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"
int ff_flac_write_header(ByteIOContext *pb, AVCodecContext *codec,
int last_block)
{
uint8_t header[8] = {
0x66, 0x4C, 0x61, 0x43, 0x00, 0x00, 0x00, 0x22
};
uint8_t *streaminfo;
enum FLACExtradataFormat format;
header[4] = last_block ? 0x80 : 0x00;
if (!ff_flac_is_extradata_valid(codec, &format, &streaminfo))
return -1;
/* write "fLaC" stream marker and first metadata block header if needed */
if (format == FLAC_EXTRADATA_FORMAT_STREAMINFO) {
put_buffer(pb, header, 8);
}
/* write STREAMINFO or full header */
put_buffer(pb, codec->extradata, codec->extradata_size);
return 0;
}
static int flac_write_block_padding(ByteIOContext *pb, unsigned int n_padding_bytes,
int last_block)
{
put_byte(pb, last_block ? 0x81 : 0x01);
put_be24(pb, n_padding_bytes);
while (n_padding_bytes > 0) {
put_byte(pb, 0);
n_padding_bytes--;
}
return 0;
}
static int flac_write_block_comment(ByteIOContext *pb, AVMetadata *m,
int last_block, int bitexact)
{
const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
unsigned int len, count;
uint8_t *p, *p0;
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);
put_buffer(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)
{
ByteIOContext *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 = url_ftell(pb);
url_fseek(pb, 8, SEEK_SET);
put_buffer(pb, streaminfo, FLAC_STREAMINFO_SIZE);
url_fseek(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)
{
put_buffer(s->pb, pkt->data, pkt->size);
put_flush_packet(s->pb);
return 0;
}
AVOutputFormat 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,
.metadata_conv = ff_vorbiscomment_metadata_conv,
};
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