FFmpeg  2.1.1
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 "libavcodec/get_bits.h"
23 #include "apetag.h"
24 #include "avformat.h"
25 #include "avio_internal.h"
26 #include "internal.h"
27 #include "id3v1.h"
28 #include "libavutil/crc.h"
29 #include "libavutil/dict.h"
30 
31 typedef struct {
32  int totalframes, currentframe;
35 } TTAContext;
36 
37 static unsigned long tta_check_crc(unsigned long checksum, const uint8_t *buf,
38  unsigned int len)
39 {
40  return av_crc(av_crc_get_table(AV_CRC_32_IEEE_LE), checksum, buf, len);
41 }
42 
43 static int tta_probe(AVProbeData *p)
44 {
45  if (AV_RL32(&p->buf[0]) == MKTAG('T', 'T', 'A', '1') &&
46  (AV_RL16(&p->buf[4]) == 1 || AV_RL16(&p->buf[4]) == 2) &&
47  AV_RL16(&p->buf[6]) > 0 &&
48  AV_RL16(&p->buf[8]) > 0 &&
49  AV_RL32(&p->buf[10]) > 0)
50  return AVPROBE_SCORE_EXTENSION + 30;
51  return 0;
52 }
53 
55 {
56  TTAContext *c = s->priv_data;
57  AVStream *st;
58  int i, channels, bps, samplerate;
59  uint64_t framepos, start_offset;
60  uint32_t nb_samples, crc;
61 
62  ff_id3v1_read(s);
63 
64  start_offset = avio_tell(s->pb);
65  ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX);
66  if (avio_rl32(s->pb) != AV_RL32("TTA1"))
67  return AVERROR_INVALIDDATA;
68 
69  avio_skip(s->pb, 2); // FIXME: flags
70  channels = avio_rl16(s->pb);
71  bps = avio_rl16(s->pb);
72  samplerate = avio_rl32(s->pb);
73  if(samplerate <= 0 || samplerate > 1000000){
74  av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
75  return AVERROR_INVALIDDATA;
76  }
77 
78  nb_samples = avio_rl32(s->pb);
79  if (!nb_samples) {
80  av_log(s, AV_LOG_ERROR, "invalid number of samples\n");
81  return AVERROR_INVALIDDATA;
82  }
83 
84  crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
85  if (crc != avio_rl32(s->pb)) {
86  av_log(s, AV_LOG_ERROR, "Header CRC error\n");
87  return AVERROR_INVALIDDATA;
88  }
89 
90  c->frame_size = samplerate * 256 / 245;
91  c->last_frame_size = nb_samples % c->frame_size;
92  if (!c->last_frame_size)
94  c->totalframes = nb_samples / c->frame_size + (c->last_frame_size < c->frame_size);
95  c->currentframe = 0;
96 
97  if(c->totalframes >= UINT_MAX/sizeof(uint32_t) || c->totalframes <= 0){
98  av_log(s, AV_LOG_ERROR, "totalframes %d invalid\n", c->totalframes);
99  return AVERROR_INVALIDDATA;
100  }
101 
102  st = avformat_new_stream(s, NULL);
103  if (!st)
104  return AVERROR(ENOMEM);
105 
106  avpriv_set_pts_info(st, 64, 1, samplerate);
107  st->start_time = 0;
108  st->duration = nb_samples;
109 
110  framepos = avio_tell(s->pb) + 4*c->totalframes + 4;
111 
112  if (ff_alloc_extradata(st->codec, avio_tell(s->pb) - start_offset))
113  return AVERROR(ENOMEM);
114 
115  avio_seek(s->pb, start_offset, SEEK_SET);
117 
118  ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX);
119  for (i = 0; i < c->totalframes; i++) {
120  uint32_t size = avio_rl32(s->pb);
121  av_add_index_entry(st, framepos, i * c->frame_size, size, 0,
123  framepos += size;
124  }
125  crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
126  if (crc != avio_rl32(s->pb)) {
127  av_log(s, AV_LOG_ERROR, "Seek table CRC error\n");
128  return AVERROR_INVALIDDATA;
129  }
130 
133  st->codec->channels = channels;
134  st->codec->sample_rate = samplerate;
136 
137  if (s->pb->seekable) {
138  int64_t pos = avio_tell(s->pb);
139  ff_ape_parse_tag(s);
140  avio_seek(s->pb, pos, SEEK_SET);
141  }
142 
143  return 0;
144 }
145 
147 {
148  TTAContext *c = s->priv_data;
149  AVStream *st = s->streams[0];
150  int size, ret;
151 
152  // FIXME!
153  if (c->currentframe >= c->totalframes)
154  return AVERROR_EOF;
155 
156  size = st->index_entries[c->currentframe].size;
157 
158  ret = av_get_packet(s->pb, pkt, size);
159  pkt->dts = st->index_entries[c->currentframe++].timestamp;
160  pkt->duration = c->currentframe == c->totalframes ? c->last_frame_size :
161  c->frame_size;
162  return ret;
163 }
164 
165 static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
166 {
167  TTAContext *c = s->priv_data;
168  AVStream *st = s->streams[stream_index];
169  int index = av_index_search_timestamp(st, timestamp, flags);
170  if (index < 0)
171  return -1;
172  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
173  return -1;
174 
175  c->currentframe = index;
176 
177  return 0;
178 }
179 
181  .name = "tta",
182  .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
183  .priv_data_size = sizeof(TTAContext),
188  .extensions = "tta",
189 };
const char * s
Definition: avisynth_c.h:668
int size
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:306
static unsigned long tta_check_crc(unsigned long checksum, const uint8_t *buf, unsigned int len)
Definition: tta.c:37
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:1675
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:478
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:3922
int64_t pos
Definition: avformat.h:609
#define AV_RL16(x)
Definition: intreadwrite.h:245
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:686
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:593
static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: tta.c:146
void ff_id3v1_read(AVFormatContext *s)
Read an ID3v1 tag.
Definition: id3v1.c:228
Definition: tta.c:45
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
Format I/O context.
Definition: avformat.h:968
uint8_t
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:248
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:823
bitstream reader API header.
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2563
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3348
int duration
Duration of this packet in AVStream-&gt;time_base units, 0 if unknown.
Definition: avcodec.h:1085
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:200
int frame_size
Definition: tta.c:33
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:1718
void * priv_data
Format private data.
Definition: avformat.h:988
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:610
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:577
int64_t ff_ape_parse_tag(AVFormatContext *s)
Read and parse an APE tag.
Definition: apetag.c:115
int totalframes
Definition: tta.c:32
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:459
int seekable
A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.
Definition: avio.h:117
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:54
ret
Definition: avfilter.c:961
AVStream ** streams
Definition: avformat.h:1016
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:341
static int tta_probe(AVProbeData *p)
Definition: tta.c:43
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length) av_pure
Calculate the CRC of a block.
Definition: crc.c:320
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:199
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:592
Stream structure.
Definition: avformat.h:667
enum AVMediaType codec_type
Definition: avcodec.h:1154
enum AVCodecID codec_id
Definition: avcodec.h:1157
int sample_rate
samples per second
Definition: avcodec.h:1873
int ff_alloc_extradata(AVCodecContext *avctx, int size)
Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:2690
AVIOContext * pb
I/O context.
Definition: avformat.h:1001
void * buf
Definition: avisynth_c.h:594
int extradata_size
Definition: avcodec.h:1255
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
#define MKTAG(a, b, c, d)
int index
Definition: gxfenc.c:89
unsigned long ffio_get_checksum(AVIOContext *s)
Definition: aviobuf.c:451
#define AVINDEX_KEYFRAME
Definition: avformat.h:616
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:256
static int flags
Definition: cpu.c:45
#define AVERROR_EOF
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:720
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:480
static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: tta.c:165
static int tta_read_header(AVFormatContext *s)
Definition: tta.c:54
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:713
static double c[64]
Main libavformat public API header.
AVInputFormat ff_tta_demuxer
Definition: tta.c:180
unsigned bps
Definition: movenc.c:962
#define AVERROR_INVALIDDATA
#define AV_RL32(x)
Definition: intreadwrite.h:275
int len
int channels
number of audio channels
Definition: avcodec.h:1874
#define AVERROR(e)
int64_t dts
Decompression timestamp in AVStream-&gt;time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1062
int last_frame_size
Definition: tta.c:34
static AVPacket pkt
Definition: demuxing.c:52
int currentframe
Definition: tta.c:32
This structure stores compressed data.
Definition: avcodec.h:1040