1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-07 11:13:41 +02:00
FFmpeg/libavformat/tta.c

190 lines
5.7 KiB
C
Raw Normal View History

/*
* 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 "apetag.h"
#include "avformat.h"
#include "avio_internal.h"
#include "internal.h"
#include "id3v1.h"
#include "libavutil/crc.h"
#include "libavutil/dict.h"
typedef struct {
int totalframes, currentframe;
2012-01-13 21:35:06 +03:00
int frame_size;
int last_frame_size;
} TTAContext;
static unsigned long tta_check_crc(unsigned long checksum, const uint8_t *buf,
unsigned int len)
{
return av_crc(av_crc_get_table(AV_CRC_32_IEEE_LE), checksum, buf, len);
}
static int tta_probe(AVProbeData *p)
{
if (AV_RL32(&p->buf[0]) == MKTAG('T', 'T', 'A', '1') &&
(AV_RL16(&p->buf[4]) == 1 || AV_RL16(&p->buf[4]) == 2) &&
AV_RL16(&p->buf[6]) > 0 &&
AV_RL16(&p->buf[8]) > 0 &&
AV_RL32(&p->buf[10]) > 0)
return AVPROBE_SCORE_EXTENSION + 30;
return 0;
}
static int tta_read_header(AVFormatContext *s)
{
TTAContext *c = s->priv_data;
AVStream *st;
int i, channels, bps, samplerate;
uint64_t framepos, start_offset;
uint32_t nb_samples, crc;
ff_id3v1_read(s);
start_offset = avio_tell(s->pb);
ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX);
if (avio_rl32(s->pb) != AV_RL32("TTA1"))
return AVERROR_INVALIDDATA;
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 AVERROR_INVALIDDATA;
}
nb_samples = avio_rl32(s->pb);
if (!nb_samples) {
av_log(s, AV_LOG_ERROR, "invalid number of samples\n");
return AVERROR_INVALIDDATA;
}
crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
if (crc != avio_rl32(s->pb)) {
av_log(s, AV_LOG_ERROR, "Header CRC error\n");
return AVERROR_INVALIDDATA;
}
2012-01-13 21:35:06 +03:00
c->frame_size = samplerate * 256 / 245;
c->last_frame_size = nb_samples % c->frame_size;
2012-01-13 21:35:06 +03:00
if (!c->last_frame_size)
c->last_frame_size = c->frame_size;
c->totalframes = nb_samples / c->frame_size + (c->last_frame_size < c->frame_size);
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 AVERROR_INVALIDDATA;
}
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 = nb_samples;
framepos = avio_tell(s->pb) + 4*c->totalframes + 4;
if (ff_alloc_extradata(st->codec, avio_tell(s->pb) - start_offset))
return AVERROR(ENOMEM);
avio_seek(s->pb, start_offset, SEEK_SET);
avio_read(s->pb, st->codec->extradata, st->codec->extradata_size);
ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX);
for (i = 0; i < c->totalframes; i++) {
uint32_t size = avio_rl32(s->pb);
2012-01-13 21:35:06 +03:00
av_add_index_entry(st, framepos, i * c->frame_size, size, 0,
AVINDEX_KEYFRAME);
framepos += size;
}
crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
if (crc != avio_rl32(s->pb)) {
av_log(s, AV_LOG_ERROR, "Seek table CRC error\n");
return AVERROR_INVALIDDATA;
}
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = AV_CODEC_ID_TTA;
st->codec->channels = channels;
st->codec->sample_rate = samplerate;
st->codec->bits_per_coded_sample = bps;
if (s->pb->seekable) {
int64_t pos = avio_tell(s->pb);
ff_ape_parse_tag(s);
avio_seek(s->pb, pos, SEEK_SET);
}
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;
2012-01-13 21:35:06 +03:00
pkt->duration = c->currentframe == c->totalframes ? c->last_frame_size :
c->frame_size;
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("TTA (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",
};