tta.c
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1 /*
2  * TTA demuxer
3  * Copyright (c) 2006 Alex Beregszaszi
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavcodec/get_bits.h"
23 #include "avformat.h"
24 #include "internal.h"
25 #include "id3v1.h"
26 #include "libavutil/dict.h"
27 
28 typedef struct {
29  int totalframes, currentframe;
30 } TTAContext;
31 
32 static int tta_probe(AVProbeData *p)
33 {
34  const uint8_t *d = p->buf;
35 
36  if (d[0] == 'T' && d[1] == 'T' && d[2] == 'A' && d[3] == '1')
37  return 80;
38  return 0;
39 }
40 
42 {
43  TTAContext *c = s->priv_data;
44  AVStream *st;
45  int i, channels, bps, samplerate, datalen, framelen;
46  uint64_t framepos, start_offset;
47 
49  ff_id3v1_read(s);
50 
51  start_offset = avio_tell(s->pb);
52  if (avio_rl32(s->pb) != AV_RL32("TTA1"))
53  return -1; // not tta file
54 
55  avio_skip(s->pb, 2); // FIXME: flags
56  channels = avio_rl16(s->pb);
57  bps = avio_rl16(s->pb);
58  samplerate = avio_rl32(s->pb);
59  if(samplerate <= 0 || samplerate > 1000000){
60  av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
61  return -1;
62  }
63 
64  datalen = avio_rl32(s->pb);
65  if(datalen < 0){
66  av_log(s, AV_LOG_ERROR, "nonsense datalen\n");
67  return -1;
68  }
69 
70  avio_skip(s->pb, 4); // header crc
71 
72  framelen = samplerate*256/245;
73  c->totalframes = datalen / framelen + ((datalen % framelen) ? 1 : 0);
74  c->currentframe = 0;
75 
76  if(c->totalframes >= UINT_MAX/sizeof(uint32_t)){
77  av_log(s, AV_LOG_ERROR, "totalframes too large\n");
78  return -1;
79  }
80 
81  st = avformat_new_stream(s, NULL);
82  if (!st)
83  return AVERROR(ENOMEM);
84 
85  avpriv_set_pts_info(st, 64, 1, samplerate);
86  st->start_time = 0;
87  st->duration = datalen;
88 
89  framepos = avio_tell(s->pb) + 4*c->totalframes + 4;
90 
91  for (i = 0; i < c->totalframes; i++) {
92  uint32_t size = avio_rl32(s->pb);
93  av_add_index_entry(st, framepos, i*framelen, size, 0, AVINDEX_KEYFRAME);
94  framepos += size;
95  }
96  avio_skip(s->pb, 4); // seektable crc
97 
100  st->codec->channels = channels;
101  st->codec->sample_rate = samplerate;
103 
104  st->codec->extradata_size = avio_tell(s->pb) - start_offset;
106  //this check is redundant as avio_read should fail
107  av_log(s, AV_LOG_ERROR, "extradata_size too large\n");
108  return -1;
109  }
111  if (!st->codec->extradata) {
112  st->codec->extradata_size = 0;
113  return AVERROR(ENOMEM);
114  }
115  avio_seek(s->pb, start_offset, SEEK_SET);
117 
118  return 0;
119 }
120 
122 {
123  TTAContext *c = s->priv_data;
124  AVStream *st = s->streams[0];
125  int size, ret;
126 
127  // FIXME!
128  if (c->currentframe >= c->totalframes)
129  return AVERROR_EOF;
130 
131  size = st->index_entries[c->currentframe].size;
132 
133  ret = av_get_packet(s->pb, pkt, size);
134  pkt->dts = st->index_entries[c->currentframe++].timestamp;
135  return ret;
136 }
137 
138 static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
139 {
140  TTAContext *c = s->priv_data;
141  AVStream *st = s->streams[stream_index];
142  int index = av_index_search_timestamp(st, timestamp, flags);
143  if (index < 0)
144  return -1;
145 
146  c->currentframe = index;
147  avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET);
148 
149  return 0;
150 }
151 
153  .name = "tta",
154  .long_name = NULL_IF_CONFIG_SMALL("True Audio"),
155  .priv_data_size = sizeof(TTAContext),
160  .extensions = "tta",
161 };
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:154
int size
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:1474
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the pts for a given stream.
Definition: utils.c:3828
int64_t pos
Definition: avformat.h:588
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:148
static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: tta.c:121
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:227
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:211
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:818
Definition: tta.c:59
AVDictionaryEntry * av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:27
Format I/O context.
Definition: avformat.h:863
Public dictionary API.
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1387
AVStream ** streams
Definition: avformat.h:908
static int read_header(FFV1Context *f)
Definition: ffv1.c:1513
static int flags
Definition: log.c:34
#define AVERROR_EOF
End of file.
Definition: error.h:51
bitstream reader API header.
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:269
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:492
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1974
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:652
#define AVINDEX_KEYFRAME
Definition: avformat.h:590
AVDictionary * metadata
Definition: avformat.h:1085
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:1516
struct TTAContext TTAContext
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:738
#define AVERROR(e)
Definition: error.h:43
int64_t timestamp
Definition: avformat.h:589
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:191
AV_RL32
Definition: bytestream.h:89
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:140
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2776
int totalframes
Definition: tta.c:29
AVCodecContext * codec
codec context
Definition: avformat.h:623
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:341
static int tta_probe(AVProbeData *p)
Definition: tta.c:32
static av_always_inline int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: avio.h:483
static int read_probe(AVProbeData *p)
Definition: img2.c:185
Stream structure.
Definition: avformat.h:620
NULL
Definition: eval.c:50
enum AVMediaType codec_type
Definition: avcodec.h:1574
int sample_rate
samples per second
Definition: avcodec.h:1456
AVIOContext * pb
Definition: avformat.h:896
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:111
int extradata_size
Definition: avcodec.h:1388
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:109
int index
Definition: gxfenc.c:73
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:497
This structure contains the data a format has to probe a file.
Definition: avformat.h:339
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:684
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:722
Main libavformat public API header.
static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: tta.c:138
int64_t start_time
Decoding: pts of the first frame of the stream, in stream time base.
Definition: avformat.h:677
AVInputFormat ff_tta_demuxer
Definition: tta.c:152
unsigned bps
Definition: movenc.c:671
int channels
number of audio channels
Definition: avcodec.h:1457
void * priv_data
Format private data.
Definition: avformat.h:883
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:907
static int tta_read_header(AVFormatContext *s, AVFormatParameters *ap)
Definition: tta.c:41
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:460
#define AV_DICT_IGNORE_SUFFIX
Definition: dict.h:62
int currentframe
Definition: tta.c:29
enum CodecID codec_id
Definition: avcodec.h:1575