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takdec.c
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1 /*
2  * Raw TAK demuxer
3  * Copyright (c) 2012 Paul B Mahol
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 "libavcodec/tak.h"
24 #include "avformat.h"
25 #include "avio_internal.h"
26 #include "internal.h"
27 #include "rawdec.h"
28 #include "apetag.h"
29 
30 typedef struct TAKDemuxContext {
32  int64_t data_end;
34 
35 static int tak_probe(AVProbeData *p)
36 {
37  if (!memcmp(p->buf, "tBaK", 4))
39  return 0;
40 }
41 
42 static unsigned long tak_check_crc(unsigned long checksum, const uint8_t *buf,
43  unsigned int len)
44 {
45  return av_crc(av_crc_get_table(AV_CRC_24_IEEE), checksum, buf, len);
46 }
47 
49 {
51  AVIOContext *pb = s->pb;
52  GetBitContext gb;
53  AVStream *st;
54  uint8_t *buffer = NULL;
55  int ret;
56 
57  st = avformat_new_stream(s, 0);
58  if (!st)
59  return AVERROR(ENOMEM);
60 
64 
65  tc->mlast_frame = 0;
66  if (avio_rl32(pb) != MKTAG('t', 'B', 'a', 'K')) {
67  avio_seek(pb, -4, SEEK_CUR);
68  return 0;
69  }
70 
71  while (!url_feof(pb)) {
72  enum TAKMetaDataType type;
73  int size;
74 
75  type = avio_r8(pb) & 0x7f;
76  size = avio_rl24(pb);
77 
78  switch (type) {
82  if (size <= 3)
83  return AVERROR_INVALIDDATA;
84 
85  buffer = av_malloc(size - 3 + FF_INPUT_BUFFER_PADDING_SIZE);
86  if (!buffer)
87  return AVERROR(ENOMEM);
88  memset(buffer + size - 3, 0, FF_INPUT_BUFFER_PADDING_SIZE);
89 
90  ffio_init_checksum(pb, tak_check_crc, 0xCE04B7U);
91  if (avio_read(pb, buffer, size - 3) != size - 3) {
92  av_freep(&buffer);
93  return AVERROR(EIO);
94  }
95  if (ffio_get_checksum(s->pb) != avio_rb24(pb)) {
96  av_log(s, AV_LOG_ERROR, "%d metadata block CRC error.\n", type);
98  av_freep(&buffer);
99  return AVERROR_INVALIDDATA;
100  }
101  }
102 
103  init_get_bits8(&gb, buffer, size - 3);
104  break;
105  case TAK_METADATA_MD5: {
106  uint8_t md5[16];
107  int i;
108 
109  if (size != 19)
110  return AVERROR_INVALIDDATA;
111  ffio_init_checksum(pb, tak_check_crc, 0xCE04B7U);
112  avio_read(pb, md5, 16);
113  if (ffio_get_checksum(s->pb) != avio_rb24(pb)) {
114  av_log(s, AV_LOG_ERROR, "MD5 metadata block CRC error.\n");
116  return AVERROR_INVALIDDATA;
117  }
118 
119  av_log(s, AV_LOG_VERBOSE, "MD5=");
120  for (i = 0; i < 16; i++)
121  av_log(s, AV_LOG_VERBOSE, "%02x", md5[i]);
122  av_log(s, AV_LOG_VERBOSE, "\n");
123  break;
124  }
125  case TAK_METADATA_END: {
126  int64_t curpos = avio_tell(pb);
127 
128  if (pb->seekable) {
129  ff_ape_parse_tag(s);
130  avio_seek(pb, curpos, SEEK_SET);
131  }
132 
133  tc->data_end += curpos;
134  return 0;
135  }
136  default:
137  ret = avio_skip(pb, size);
138  if (ret < 0)
139  return ret;
140  }
141 
142  if (type == TAK_METADATA_STREAMINFO) {
143  TAKStreamInfo ti;
144 
145  avpriv_tak_parse_streaminfo(&gb, &ti);
146  if (ti.samples > 0)
147  st->duration = ti.samples;
148  st->codec->bits_per_coded_sample = ti.bps;
149  if (ti.ch_layout)
150  st->codec->channel_layout = ti.ch_layout;
151  st->codec->sample_rate = ti.sample_rate;
152  st->codec->channels = ti.channels;
153  st->start_time = 0;
154  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
155  st->codec->extradata = buffer;
156  st->codec->extradata_size = size - 3;
157  buffer = NULL;
158  } else if (type == TAK_METADATA_LAST_FRAME) {
159  if (size != 11)
160  return AVERROR_INVALIDDATA;
161  tc->mlast_frame = 1;
164  av_freep(&buffer);
165  } else if (type == TAK_METADATA_ENCODER) {
166  av_log(s, AV_LOG_VERBOSE, "encoder version: %0X\n",
168  av_freep(&buffer);
169  }
170  }
171 
172  return AVERROR_EOF;
173 }
174 
176 {
178  int ret;
179 
180  if (tc->mlast_frame) {
181  AVIOContext *pb = s->pb;
182  int64_t size, left;
183 
184  left = tc->data_end - avio_tell(pb);
185  size = FFMIN(left, 1024);
186  if (size <= 0)
187  return AVERROR_EOF;
188 
189  ret = av_get_packet(pb, pkt, size);
190  if (ret < 0)
191  return ret;
192 
193  pkt->stream_index = 0;
194  } else {
195  ret = ff_raw_read_partial_packet(s, pkt);
196  }
197 
198  return ret;
199 }
200 
202  .name = "tak",
203  .long_name = NULL_IF_CONFIG_SMALL("raw TAK"),
204  .priv_data_size = sizeof(TAKDemuxContext),
209  .extensions = "tak",
210  .raw_codec_id = AV_CODEC_ID_TAK,
211 };