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aiffdec.c
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1 /*
2  * AIFF/AIFF-C demuxer
3  * Copyright (c) 2006 Patrick Guimond
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/intreadwrite.h"
23 #include "libavutil/mathematics.h"
24 #include "libavutil/dict.h"
25 #include "avformat.h"
26 #include "internal.h"
27 #include "pcm.h"
28 #include "aiff.h"
29 #include "isom.h"
30 #include "id3v2.h"
31 #include "mov_chan.h"
32 
33 #define AIFF 0
34 #define AIFF_C_VERSION1 0xA2805140
35 
36 typedef struct {
37  int64_t data_end;
40 
42 {
43  if (bps <= 8)
44  return AV_CODEC_ID_PCM_S8;
45  if (bps <= 16)
46  return AV_CODEC_ID_PCM_S16BE;
47  if (bps <= 24)
48  return AV_CODEC_ID_PCM_S24BE;
49  if (bps <= 32)
50  return AV_CODEC_ID_PCM_S32BE;
51 
52  /* bigger than 32 isn't allowed */
53  return AV_CODEC_ID_NONE;
54 }
55 
56 /* returns the size of the found tag */
57 static int get_tag(AVIOContext *pb, uint32_t * tag)
58 {
59  int size;
60 
61  if (avio_feof(pb))
62  return AVERROR(EIO);
63 
64  *tag = avio_rl32(pb);
65  size = avio_rb32(pb);
66 
67  if (size < 0)
68  size = 0x7fffffff;
69 
70  return size;
71 }
72 
73 /* Metadata string read */
74 static void get_meta(AVFormatContext *s, const char *key, int size)
75 {
76  uint8_t *str = av_malloc(size+1);
77 
78  if (str) {
79  int res = avio_read(s->pb, str, size);
80  if (res < 0){
81  av_free(str);
82  return;
83  }
84  size += (size&1)-res;
85  str[res] = 0;
87  }else
88  size+= size&1;
89 
90  avio_skip(s->pb, size);
91 }
92 
93 /* Returns the number of sound data frames or negative on error */
94 static unsigned int get_aiff_header(AVFormatContext *s, int size,
95  unsigned version)
96 {
97  AVIOContext *pb = s->pb;
98  AVCodecContext *codec = s->streams[0]->codec;
99  AIFFInputContext *aiff = s->priv_data;
100  int exp;
101  uint64_t val;
102  double sample_rate;
103  unsigned int num_frames;
104 
105  if (size & 1)
106  size++;
108  codec->channels = avio_rb16(pb);
109  num_frames = avio_rb32(pb);
110  codec->bits_per_coded_sample = avio_rb16(pb);
111 
112  exp = avio_rb16(pb);
113  val = avio_rb64(pb);
114  sample_rate = ldexp(val, exp - 16383 - 63);
115  codec->sample_rate = sample_rate;
116  size -= 18;
117 
118  /* get codec id for AIFF-C */
119  if (size < 4) {
120  version = AIFF;
121  } else if (version == AIFF_C_VERSION1) {
122  codec->codec_tag = avio_rl32(pb);
124  size -= 4;
125  }
126 
127  if (version != AIFF_C_VERSION1 || codec->codec_id == AV_CODEC_ID_PCM_S16BE) {
130  aiff->block_duration = 1;
131  } else {
132  switch (codec->codec_id) {
138  aiff->block_duration = 1;
139  break;
141  codec->block_align = 34*codec->channels;
142  break;
143  case AV_CODEC_ID_MACE3:
144  codec->block_align = 2*codec->channels;
145  break;
147  codec->bits_per_coded_sample = 5;
149  case AV_CODEC_ID_MACE6:
150  codec->block_align = 1*codec->channels;
151  break;
152  case AV_CODEC_ID_GSM:
153  codec->block_align = 33;
154  break;
155  default:
156  aiff->block_duration = 1;
157  break;
158  }
159  if (codec->block_align > 0)
161  codec->block_align);
162  }
163 
164  /* Block align needs to be computed in all cases, as the definition
165  * is specific to applications -> here we use the WAVE format definition */
166  if (!codec->block_align)
167  codec->block_align = (av_get_bits_per_sample(codec->codec_id) * codec->channels) >> 3;
168 
169  if (aiff->block_duration) {
170  codec->bit_rate = codec->sample_rate * (codec->block_align << 3) /
171  aiff->block_duration;
172  }
173 
174  /* Chunk is over */
175  if (size)
176  avio_skip(pb, size);
177 
178  return num_frames;
179 }
180 
181 static int aiff_probe(AVProbeData *p)
182 {
183  /* check file header */
184  if (p->buf[0] == 'F' && p->buf[1] == 'O' &&
185  p->buf[2] == 'R' && p->buf[3] == 'M' &&
186  p->buf[8] == 'A' && p->buf[9] == 'I' &&
187  p->buf[10] == 'F' && (p->buf[11] == 'F' || p->buf[11] == 'C'))
188  return AVPROBE_SCORE_MAX;
189  else
190  return 0;
191 }
192 
193 /* aiff input */
195 {
196  int ret, size, filesize;
197  int64_t offset = 0, position;
198  uint32_t tag;
199  unsigned version = AIFF_C_VERSION1;
200  AVIOContext *pb = s->pb;
201  AVStream * st;
202  AIFFInputContext *aiff = s->priv_data;
203  ID3v2ExtraMeta *id3v2_extra_meta = NULL;
204 
205  /* check FORM header */
206  filesize = get_tag(pb, &tag);
207  if (filesize < 0 || tag != MKTAG('F', 'O', 'R', 'M'))
208  return AVERROR_INVALIDDATA;
209 
210  /* AIFF data type */
211  tag = avio_rl32(pb);
212  if (tag == MKTAG('A', 'I', 'F', 'F')) /* Got an AIFF file */
213  version = AIFF;
214  else if (tag != MKTAG('A', 'I', 'F', 'C')) /* An AIFF-C file then */
215  return AVERROR_INVALIDDATA;
216 
217  filesize -= 4;
218 
219  st = avformat_new_stream(s, NULL);
220  if (!st)
221  return AVERROR(ENOMEM);
222 
223  while (filesize > 0) {
224  /* parse different chunks */
225  size = get_tag(pb, &tag);
226  if (size < 0)
227  return size;
228 
229  filesize -= size + 8;
230 
231  switch (tag) {
232  case MKTAG('C', 'O', 'M', 'M'): /* Common chunk */
233  /* Then for the complete header info */
234  st->nb_frames = get_aiff_header(s, size, version);
235  if (st->nb_frames < 0)
236  return st->nb_frames;
237  if (offset > 0) // COMM is after SSND
238  goto got_sound;
239  break;
240  case MKTAG('I', 'D', '3', ' '):
241  position = avio_tell(pb);
242  ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta, size);
243  if (id3v2_extra_meta)
244  if ((ret = ff_id3v2_parse_apic(s, &id3v2_extra_meta)) < 0) {
245  ff_id3v2_free_extra_meta(&id3v2_extra_meta);
246  return ret;
247  }
248  ff_id3v2_free_extra_meta(&id3v2_extra_meta);
249  if (position + size > avio_tell(pb))
250  avio_skip(pb, position + size - avio_tell(pb));
251  break;
252  case MKTAG('F', 'V', 'E', 'R'): /* Version chunk */
253  version = avio_rb32(pb);
254  break;
255  case MKTAG('N', 'A', 'M', 'E'): /* Sample name chunk */
256  get_meta(s, "title" , size);
257  break;
258  case MKTAG('A', 'U', 'T', 'H'): /* Author chunk */
259  get_meta(s, "author" , size);
260  break;
261  case MKTAG('(', 'c', ')', ' '): /* Copyright chunk */
262  get_meta(s, "copyright", size);
263  break;
264  case MKTAG('A', 'N', 'N', 'O'): /* Annotation chunk */
265  get_meta(s, "comment" , size);
266  break;
267  case MKTAG('S', 'S', 'N', 'D'): /* Sampled sound chunk */
268  aiff->data_end = avio_tell(pb) + size;
269  offset = avio_rb32(pb); /* Offset of sound data */
270  avio_rb32(pb); /* BlockSize... don't care */
271  offset += avio_tell(pb); /* Compute absolute data offset */
272  if (st->codec->block_align && !pb->seekable) /* Assume COMM already parsed */
273  goto got_sound;
274  if (!pb->seekable) {
275  av_log(s, AV_LOG_ERROR, "file is not seekable\n");
276  return -1;
277  }
278  avio_skip(pb, size - 8);
279  break;
280  case MKTAG('w', 'a', 'v', 'e'):
281  if ((uint64_t)size > (1<<30))
282  return -1;
283  if (ff_get_extradata(st->codec, pb, size) < 0)
284  return AVERROR(ENOMEM);
285  if (st->codec->codec_id == AV_CODEC_ID_QDM2 && size>=12*4 && !st->codec->block_align) {
286  st->codec->block_align = AV_RB32(st->codec->extradata+11*4);
287  aiff->block_duration = AV_RB32(st->codec->extradata+9*4);
288  } else if (st->codec->codec_id == AV_CODEC_ID_QCELP) {
289  char rate = 0;
290  if (size >= 25)
291  rate = st->codec->extradata[24];
292  switch (rate) {
293  case 'H': // RATE_HALF
294  st->codec->block_align = 17;
295  break;
296  case 'F': // RATE_FULL
297  default:
298  st->codec->block_align = 35;
299  }
300  aiff->block_duration = 160;
301  st->codec->bit_rate = st->codec->sample_rate * (st->codec->block_align << 3) /
302  aiff->block_duration;
303  }
304  break;
305  case MKTAG('C','H','A','N'):
306  if(ff_mov_read_chan(s, pb, st, size) < 0)
307  return AVERROR_INVALIDDATA;
308  break;
309  default: /* Jump */
310  if (size & 1) /* Always even aligned */
311  size++;
312  avio_skip(pb, size);
313  }
314  }
315 
316 got_sound:
317  if (!st->codec->block_align) {
318  av_log(s, AV_LOG_ERROR, "could not find COMM tag or invalid block_align value\n");
319  return -1;
320  }
321 
322  /* Now positioned, get the sound data start and end */
323  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
324  st->start_time = 0;
325  st->duration = st->nb_frames * aiff->block_duration;
326 
327  /* Position the stream at the first block */
328  avio_seek(pb, offset, SEEK_SET);
329 
330  return 0;
331 }
332 
333 #define MAX_SIZE 4096
334 
336  AVPacket *pkt)
337 {
338  AVStream *st = s->streams[0];
339  AIFFInputContext *aiff = s->priv_data;
340  int64_t max_size;
341  int res, size;
342 
343  /* calculate size of remaining data */
344  max_size = aiff->data_end - avio_tell(s->pb);
345  if (max_size <= 0)
346  return AVERROR_EOF;
347 
348  /* Now for that packet */
349  switch (st->codec->codec_id) {
351  case AV_CODEC_ID_GSM:
352  case AV_CODEC_ID_QDM2:
353  case AV_CODEC_ID_QCELP:
354  size = st->codec->block_align;
355  break;
356  default:
357  size = (MAX_SIZE / st->codec->block_align) * st->codec->block_align;
358  }
359  size = FFMIN(max_size, size);
360  res = av_get_packet(s->pb, pkt, size);
361  if (res < 0)
362  return res;
363 
364  if (size >= st->codec->block_align)
365  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
366  /* Only one stream in an AIFF file */
367  pkt->stream_index = 0;
368  pkt->duration = (res / st->codec->block_align) * aiff->block_duration;
369  return 0;
370 }
371 
373  .name = "aiff",
374  .long_name = NULL_IF_CONFIG_SMALL("Audio IFF"),
375  .priv_data_size = sizeof(AIFFInputContext),
380  .codec_tag = (const AVCodecTag* const []){ ff_codec_aiff_tags, 0 },
381 };