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/*
* Raw FLAC demuxer
* Copyright (c) 2001 Fabrice Bellard
*
* 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 "raw.h"
#include "id3v2.h"
#include "oggdec.h"
static int flac_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
uint8_t buf[ID3v2_HEADER_SIZE];
int ret, metadata_last=0, metadata_type, metadata_size, found_streaminfo=0;
uint8_t header[4];
uint8_t *buffer=NULL;
AVStream *st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_FLAC;
st->need_parsing = AVSTREAM_PARSE_FULL;
/* the parameters will be extracted from the compressed bitstream */
/* skip ID3v2 header if found */
ret = get_buffer(s->pb, buf, ID3v2_HEADER_SIZE);
if (ret == ID3v2_HEADER_SIZE && ff_id3v2_match(buf)) {
int len = ff_id3v2_tag_len(buf);
url_fseek(s->pb, len - ID3v2_HEADER_SIZE, SEEK_CUR);
} else {
url_fseek(s->pb, 0, SEEK_SET);
}
/* if fLaC marker is not found, assume there is no header */
if (get_le32(s->pb) != MKTAG('f','L','a','C')) {
url_fseek(s->pb, -4, SEEK_CUR);
return 0;
}
/* process metadata blocks */
while (!url_feof(s->pb) && !metadata_last) {
get_buffer(s->pb, header, 4);
ff_flac_parse_block_header(header, &metadata_last, &metadata_type,
&metadata_size);
switch (metadata_type) {
/* allocate and read metadata block for supported types */
case FLAC_METADATA_TYPE_STREAMINFO:
case FLAC_METADATA_TYPE_VORBIS_COMMENT:
buffer = av_mallocz(metadata_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!buffer) {
return AVERROR_NOMEM;
}
if (get_buffer(s->pb, buffer, metadata_size) != metadata_size) {
av_freep(&buffer);
return AVERROR_IO;
}
break;
/* skip metadata block for unsupported types */
default:
ret = url_fseek(s->pb, metadata_size, SEEK_CUR);
if (ret < 0)
return ret;
}
if (metadata_type == FLAC_METADATA_TYPE_STREAMINFO) {
FLACStreaminfo si;
/* STREAMINFO can only occur once */
if (found_streaminfo) {
av_freep(&buffer);
return AVERROR_INVALIDDATA;
}
if (metadata_size != FLAC_STREAMINFO_SIZE) {
av_freep(&buffer);
return AVERROR_INVALIDDATA;
}
found_streaminfo = 1;
st->codec->extradata = buffer;
st->codec->extradata_size = metadata_size;
buffer = NULL;
/* get codec params from STREAMINFO header */
ff_flac_parse_streaminfo(st->codec, &si, st->codec->extradata);
/* set time base and duration */
if (si.samplerate > 0) {
av_set_pts_info(st, 64, 1, si.samplerate);
if (si.samples > 0)
st->duration = si.samples;
}
} else {
/* STREAMINFO must be the first block */
if (!found_streaminfo) {
av_freep(&buffer);
return AVERROR_INVALIDDATA;
}
/* process supported blocks other than STREAMINFO */
if (metadata_type == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
if (vorbis_comment(s, buffer, metadata_size)) {
av_log(s, AV_LOG_WARNING, "error parsing VorbisComment metadata\n");
}
}
av_freep(&buffer);
}
}
return 0;
}
static int flac_probe(AVProbeData *p)
{
uint8_t *bufptr = p->buf;
uint8_t *end = p->buf + p->buf_size;
if(ff_id3v2_match(bufptr))
bufptr += ff_id3v2_tag_len(bufptr);
if(bufptr > end-4 || memcmp(bufptr, "fLaC", 4)) return 0;
else return AVPROBE_SCORE_MAX/2;
}
AVInputFormat flac_demuxer = {
"flac",
NULL_IF_CONFIG_SMALL("raw FLAC"),
0,
flac_probe,
flac_read_header,
ff_raw_read_partial_packet,
.flags= AVFMT_GENERIC_INDEX,
.extensions = "flac",
.value = CODEC_ID_FLAC,
};
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