FFmpeg: libavformat/tta.c Source File

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tta.c
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1 /*
2  * TTA demuxer
3  * Copyright (c) 2006 Alex Beregszaszi
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/crc.h"
23 #include "libavutil/dict.h"
24 #include "libavutil/intreadwrite.h"
25 
26 #include "apetag.h"
27 #include "avformat.h"
28 #include "avio_internal.h"
29 #include "internal.h"
30 #include "id3v1.h"
31 
32 typedef struct TTAContext {
33   int totalframes, currentframe;
34   int frame_size;
35   int last_frame_size;
36 } TTAContext;
37 
38  static int tta_probe(AVProbeData *p)
39 {
40  if (AV_RL32(&p->buf[0]) == MKTAG('T', 'T', 'A', '1') &&
41  (AV_RL16(&p->buf[4]) == 1 || AV_RL16(&p->buf[4]) == 2) &&
42  AV_RL16(&p->buf[6]) > 0 &&
43  AV_RL16(&p->buf[8]) > 0 &&
44  AV_RL32(&p->buf[10]) > 0)
45  return AVPROBE_SCORE_EXTENSION + 30;
46  return 0;
47 }
48 
49  static int tta_read_header(AVFormatContext *s)
50 {
51  TTAContext *c = s->priv_data;
52  AVStream *st;
53  int i, channels, bps, samplerate;
54  int64_t framepos, start_offset;
55  uint32_t nb_samples, crc;
56 
57  ff_id3v1_read(s);
58 
59  start_offset = avio_tell(s->pb);
60  if (start_offset < 0)
61  return start_offset;
62  ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
63  if (avio_rl32(s->pb) != AV_RL32("TTA1"))
64  return AVERROR_INVALIDDATA;
65 
66  avio_skip(s->pb, 2); // FIXME: flags
67  channels = avio_rl16(s->pb);
68  bps = avio_rl16(s->pb);
69  samplerate = avio_rl32(s->pb);
70  if(samplerate <= 0 || samplerate > 1000000){
71  av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
72  return AVERROR_INVALIDDATA;
73  }
74 
75  nb_samples = avio_rl32(s->pb);
76  if (!nb_samples) {
77  av_log(s, AV_LOG_ERROR, "invalid number of samples\n");
78  return AVERROR_INVALIDDATA;
79  }
80 
81  crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
82  if (crc != avio_rl32(s->pb) && s->error_recognition & AV_EF_CRCCHECK) {
83  av_log(s, AV_LOG_ERROR, "Header CRC error\n");
84  return AVERROR_INVALIDDATA;
85  }
86 
87  c->frame_size = samplerate * 256 / 245;
88  c->last_frame_size = nb_samples % c->frame_size;
89  if (!c->last_frame_size)
90  c->last_frame_size = c->frame_size;
91  c->totalframes = nb_samples / c->frame_size + (c->last_frame_size < c->frame_size);
92  c->currentframe = 0;
93 
94  if(c->totalframes >= UINT_MAX/sizeof(uint32_t) || c->totalframes <= 0){
95  av_log(s, AV_LOG_ERROR, "totalframes %d invalid\n", c->totalframes);
96  return AVERROR_INVALIDDATA;
97  }
98 
99  st = avformat_new_stream(s, NULL);
100  if (!st)
101  return AVERROR(ENOMEM);
102 
103  avpriv_set_pts_info(st, 64, 1, samplerate);
104  st->start_time = 0;
105  st->duration = nb_samples;
106 
107  framepos = avio_tell(s->pb);
108  if (framepos < 0)
109  return framepos;
110  framepos += 4 * c->totalframes + 4;
111 
112  if (ff_alloc_extradata(st->codecpar, avio_tell(s->pb) - start_offset))
113  return AVERROR(ENOMEM);
114 
115  avio_seek(s->pb, start_offset, SEEK_SET);
116  avio_read(s->pb, st->codecpar->extradata, st->codecpar->extradata_size);
117 
118  ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
119  for (i = 0; i < c->totalframes; i++) {
120  uint32_t size = avio_rl32(s->pb);
121  int r;
122  if ((r = av_add_index_entry(st, framepos, i * c->frame_size, size, 0,
123  AVINDEX_KEYFRAME)) < 0)
124  return r;
125  framepos += size;
126  }
127  crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
128  if (crc != avio_rl32(s->pb) && s->error_recognition & AV_EF_CRCCHECK) {
129  av_log(s, AV_LOG_ERROR, "Seek table CRC error\n");
130  return AVERROR_INVALIDDATA;
131  }
132 
133  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
134  st->codecpar->codec_id = AV_CODEC_ID_TTA;
135  st->codecpar->channels = channels;
136  st->codecpar->sample_rate = samplerate;
137  st->codecpar->bits_per_coded_sample = bps;
138 
139  if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
140  int64_t pos = avio_tell(s->pb);
141  ff_ape_parse_tag(s);
142  avio_seek(s->pb, pos, SEEK_SET);
143  }
144 
145  return 0;
146 }
147 
148  static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
149 {
150  TTAContext *c = s->priv_data;
151  AVStream *st = s->streams[0];
152  int size, ret;
153 
154  // FIXME!
155  if (c->currentframe >= c->totalframes)
156  return AVERROR_EOF;
157 
158  if (st->nb_index_entries < c->totalframes) {
159  av_log(s, AV_LOG_ERROR, "Index entry disappeared\n");
160  return AVERROR_INVALIDDATA;
161  }
162 
163  size = st->index_entries[c->currentframe].size;
164 
165  ret = av_get_packet(s->pb, pkt, size);
166  pkt->dts = st->index_entries[c->currentframe++].timestamp;
167  pkt->duration = c->currentframe == c->totalframes ? c->last_frame_size :
168  c->frame_size;
169  return ret;
170 }
171 
172  static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
173 {
174  TTAContext *c = s->priv_data;
175  AVStream *st = s->streams[stream_index];
176  int index = av_index_search_timestamp(st, timestamp, flags);
177  if (index < 0)
178  return -1;
179  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
180  return -1;
181 
182  c->currentframe = index;
183 
184  return 0;
185 }
186 
187  AVInputFormat ff_tta_demuxer = {
188  .name = "tta",
189  .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
190  .priv_data_size = sizeof(TTAContext),
191  .read_probe = tta_probe,
192  .read_header = tta_read_header,
193  .read_packet = tta_read_packet,
194  .read_seek = tta_read_seek,
195  .extensions = "tta",
196 };
NULL
#define NULL
Definition: coverity.c:32
s
const char * s
Definition: avisynth_c.h:768
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
av_add_index_entry
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:2038
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4820
AVIndexEntry::pos
int64_t pos
Definition: avformat.h:803
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
channels
channels
Definition: aptx.c:30
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3884
tta_read_packet
static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: tta.c:148
ff_id3v1_read
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:235
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
AVStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1102
TTAContext
Definition: tta.c:48
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AVIndexEntry::size
int size
Definition: avformat.h:815
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
AVFormatContext
Format I/O context.
Definition: avformat.h:1342
dict.h
Public dictionary API.
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1448
ff_crcEDB88320_update
unsigned long ff_crcEDB88320_update(unsigned long checksum, const uint8_t *buf, unsigned int len)
Definition: aviobuf.c:607
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4450
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1410
crc.h
Public header for CRC hash function implementation.
avio_internal.h
flags
static int flags
Definition: log.c:55
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
av_get_packet
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:310
size
ptrdiff_t size
Definition: opengl_enc.c:101
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
TTAContext::frame_size
int frame_size
Definition: tta.c:34
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:810
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2147
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
AVERROR
#define AVERROR(e)
Definition: error.h:43
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:804
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
r
const char * r
Definition: vf_curves.c:111
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3880
AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ff_ape_parse_tag
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:118
TTAContext::totalframes
int totalframes
Definition: tta.c:33
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3902
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
ffio_init_checksum
void ffio_init_checksum(AVIOContext *s, unsigned long(*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum)
Definition: aviobuf.c:627
AVIOContext::seekable
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:260
ff_alloc_extradata
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3280
read_probe
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
tta_probe
static int tta_probe(AVProbeData *p)
Definition: tta.c:38
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
AVStream
Stream structure.
Definition: avformat.h:873
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVIO_SEEKABLE_NORMAL
#define AVIO_SEEKABLE_NORMAL
Seeking works like for a local file.
Definition: avio.h:40
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1384
AVStream::nb_index_entries
int nb_index_entries
Definition: avformat.h:1104
AV_CODEC_ID_TTA
Definition: avcodec.h:573
index
int index
Definition: gxfenc.c:89
ffio_get_checksum
unsigned long ffio_get_checksum(AVIOContext *s)
Definition: aviobuf.c:619
AV_EF_CRCCHECK
#define AV_EF_CRCCHECK
Verify checksums embedded in the bitstream (could be of either encoded or decoded data...
Definition: avcodec.h:2650
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: avcodec.h:3994
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:754
avformat.h
Main libavformat public API header.
tta_read_seek
static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: tta.c:172
tta_read_header
static int tta_read_header(AVFormatContext *s)
Definition: tta.c:49
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:912
c
static double c[64]
Definition: vsrc_mptestsrc.c:87
AVFormatContext::error_recognition
int error_recognition
Error recognition; higher values will detect more errors but may misdetect some more or less valid pa...
Definition: avformat.h:1607
ff_tta_demuxer
AVInputFormat ff_tta_demuxer
Definition: tta.c:187
bps
unsigned bps
Definition: movenc.c:1456
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1370
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:3926
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3898
AVCodecParameters::channels
int channels
Audio only.
Definition: avcodec.h:3990
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1429
TTAContext::last_frame_size
int last_frame_size
Definition: tta.c:35
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1020
TTAContext::currentframe
int currentframe
Definition: tta.c:33
MKTAG
#define MKTAG(a, b, c, d)
Definition: common.h:366
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
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