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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 "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 TTAContext {
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  int64_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  if (start_offset < 0)
66  return start_offset;
67  ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX);
68  if (avio_rl32(s->pb) != AV_RL32("TTA1"))
69  return AVERROR_INVALIDDATA;
70 
71  avio_skip(s->pb, 2); // FIXME: flags
72  channels = avio_rl16(s->pb);
73  bps = avio_rl16(s->pb);
74  samplerate = avio_rl32(s->pb);
75  if(samplerate <= 0 || samplerate > 1000000){
76  av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
77  return AVERROR_INVALIDDATA;
78  }
79 
80  nb_samples = avio_rl32(s->pb);
81  if (!nb_samples) {
82  av_log(s, AV_LOG_ERROR, "invalid number of samples\n");
83  return AVERROR_INVALIDDATA;
84  }
85 
86  crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
87  if (crc != avio_rl32(s->pb) && s->error_recognition & AV_EF_CRCCHECK) {
88  av_log(s, AV_LOG_ERROR, "Header CRC error\n");
89  return AVERROR_INVALIDDATA;
90  }
91 
92  c->frame_size = samplerate * 256 / 245;
93  c->last_frame_size = nb_samples % c->frame_size;
94  if (!c->last_frame_size)
96  c->totalframes = nb_samples / c->frame_size + (c->last_frame_size < c->frame_size);
97  c->currentframe = 0;
98 
99  if(c->totalframes >= UINT_MAX/sizeof(uint32_t) || c->totalframes <= 0){
100  av_log(s, AV_LOG_ERROR, "totalframes %d invalid\n", c->totalframes);
101  return AVERROR_INVALIDDATA;
102  }
103 
104  st = avformat_new_stream(s, NULL);
105  if (!st)
106  return AVERROR(ENOMEM);
107 
108  avpriv_set_pts_info(st, 64, 1, samplerate);
109  st->start_time = 0;
110  st->duration = nb_samples;
111 
112  framepos = avio_tell(s->pb);
113  if (framepos < 0)
114  return framepos;
115  framepos += 4 * c->totalframes + 4;
116 
117  if (ff_alloc_extradata(st->codec, avio_tell(s->pb) - start_offset))
118  return AVERROR(ENOMEM);
119 
120  avio_seek(s->pb, start_offset, SEEK_SET);
122 
123  ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX);
124  for (i = 0; i < c->totalframes; i++) {
125  uint32_t size = avio_rl32(s->pb);
126  int r;
127  if ((r = av_add_index_entry(st, framepos, i * c->frame_size, size, 0,
128  AVINDEX_KEYFRAME)) < 0)
129  return r;
130  framepos += size;
131  }
132  crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
133  if (crc != avio_rl32(s->pb) && s->error_recognition & AV_EF_CRCCHECK) {
134  av_log(s, AV_LOG_ERROR, "Seek table CRC error\n");
135  return AVERROR_INVALIDDATA;
136  }
137 
140  st->codec->channels = channels;
141  st->codec->sample_rate = samplerate;
143 
144  if (s->pb->seekable) {
145  int64_t pos = avio_tell(s->pb);
146  ff_ape_parse_tag(s);
147  avio_seek(s->pb, pos, SEEK_SET);
148  }
149 
150  return 0;
151 }
152 
154 {
155  TTAContext *c = s->priv_data;
156  AVStream *st = s->streams[0];
157  int size, ret;
158 
159  // FIXME!
160  if (c->currentframe >= c->totalframes)
161  return AVERROR_EOF;
162 
163  if (st->nb_index_entries < c->totalframes) {
164  av_log(s, AV_LOG_ERROR, "Index entry disappeared\n");
165  return AVERROR_INVALIDDATA;
166  }
167 
168  size = st->index_entries[c->currentframe].size;
169 
170  ret = av_get_packet(s->pb, pkt, size);
171  pkt->dts = st->index_entries[c->currentframe++].timestamp;
172  pkt->duration = c->currentframe == c->totalframes ? c->last_frame_size :
173  c->frame_size;
174  return ret;
175 }
176 
177 static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
178 {
179  TTAContext *c = s->priv_data;
180  AVStream *st = s->streams[stream_index];
181  int index = av_index_search_timestamp(st, timestamp, flags);
182  if (index < 0)
183  return -1;
184  if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
185  return -1;
186 
187  c->currentframe = index;
188 
189  return 0;
190 }
191 
193  .name = "tta",
194  .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
195  .priv_data_size = sizeof(TTAContext),
200  .extensions = "tta",
201 };