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/*
* TTA demuxer
* Copyright (c) 2006 Alex Beregszaszi
*
* 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/get_bits.h"
#include "avformat.h"
#include "internal.h"
#include "id3v1.h"
#include "libavutil/dict.h"
typedef struct {
int totalframes, currentframe;
} TTAContext;
static int tta_probe(AVProbeData *p)
{
const uint8_t *d = p->buf;
if (d[0] == 'T' && d[1] == 'T' && d[2] == 'A' && d[3] == '1')
return 80;
return 0;
}
static int tta_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
TTAContext *c = s->priv_data;
AVStream *st;
int i, channels, bps, samplerate, datalen, framelen;
uint64_t framepos, start_offset;
if (!av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX))
ff_id3v1_read(s);
start_offset = avio_tell(s->pb);
if (avio_rl32(s->pb) != AV_RL32("TTA1"))
return -1; // not tta file
avio_skip(s->pb, 2); // FIXME: flags
channels = avio_rl16(s->pb);
bps = avio_rl16(s->pb);
samplerate = avio_rl32(s->pb);
if(samplerate <= 0 || samplerate > 1000000){
av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
return -1;
}
datalen = avio_rl32(s->pb);
if(datalen < 0){
av_log(s, AV_LOG_ERROR, "nonsense datalen\n");
return -1;
}
avio_skip(s->pb, 4); // header crc
framelen = samplerate*256/245;
c->totalframes = datalen / framelen + ((datalen % framelen) ? 1 : 0);
c->currentframe = 0;
if(c->totalframes >= UINT_MAX/sizeof(uint32_t) || c->totalframes <= 0){
av_log(s, AV_LOG_ERROR, "totalframes %d invalid\n", c->totalframes);
return -1;
}
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 64, 1, samplerate);
st->start_time = 0;
st->duration = datalen;
framepos = avio_tell(s->pb) + 4*c->totalframes + 4;
for (i = 0; i < c->totalframes; i++) {
uint32_t size = avio_rl32(s->pb);
av_add_index_entry(st, framepos, i*framelen, size, 0, AVINDEX_KEYFRAME);
framepos += size;
}
avio_skip(s->pb, 4); // seektable crc
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_TTA;
st->codec->channels = channels;
st->codec->sample_rate = samplerate;
st->codec->bits_per_coded_sample = bps;
st->codec->extradata_size = avio_tell(s->pb) - start_offset;
if(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE <= (unsigned)st->codec->extradata_size){
//this check is redundant as avio_read should fail
av_log(s, AV_LOG_ERROR, "extradata_size too large\n");
return -1;
}
st->codec->extradata = av_mallocz(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata) {
st->codec->extradata_size = 0;
return AVERROR(ENOMEM);
}
avio_seek(s->pb, start_offset, SEEK_SET);
avio_read(s->pb, st->codec->extradata, st->codec->extradata_size);
return 0;
}
static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
{
TTAContext *c = s->priv_data;
AVStream *st = s->streams[0];
int size, ret;
// FIXME!
if (c->currentframe >= c->totalframes)
return AVERROR_EOF;
size = st->index_entries[c->currentframe].size;
ret = av_get_packet(s->pb, pkt, size);
pkt->dts = st->index_entries[c->currentframe++].timestamp;
return ret;
}
static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
{
TTAContext *c = s->priv_data;
AVStream *st = s->streams[stream_index];
int index = av_index_search_timestamp(st, timestamp, flags);
if (index < 0)
return -1;
if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
return -1;
c->currentframe = index;
return 0;
}
AVInputFormat ff_tta_demuxer = {
.name = "tta",
.long_name = NULL_IF_CONFIG_SMALL("True Audio"),
.priv_data_size = sizeof(TTAContext),
.read_probe = tta_probe,
.read_header = tta_read_header,
.read_packet = tta_read_packet,
.read_seek = tta_read_seek,
.extensions = "tta",
};
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