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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 (url_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 (version == AIFF_C_VERSION1) {
120  codec->codec_tag = avio_rl32(pb);
122  size -= 4;
123  }
124 
125  if (version != AIFF_C_VERSION1 || codec->codec_id == AV_CODEC_ID_PCM_S16BE) {
128  aiff->block_duration = 1;
129  } else {
130  switch (codec->codec_id) {
136  aiff->block_duration = 1;
137  break;
139  codec->block_align = 34*codec->channels;
140  break;
141  case AV_CODEC_ID_MACE3:
142  codec->block_align = 2*codec->channels;
143  break;
144  case AV_CODEC_ID_MACE6:
145  codec->block_align = 1*codec->channels;
146  break;
147  case AV_CODEC_ID_GSM:
148  codec->block_align = 33;
149  break;
150  case AV_CODEC_ID_QCELP:
151  codec->block_align = 35;
152  break;
153  default:
154  aiff->block_duration = 1;
155  break;
156  }
157  if (codec->block_align > 0)
159  codec->block_align);
160  }
161 
162  /* Block align needs to be computed in all cases, as the definition
163  * is specific to applications -> here we use the WAVE format definition */
164  if (!codec->block_align)
165  codec->block_align = (av_get_bits_per_sample(codec->codec_id) * codec->channels) >> 3;
166 
167  if (aiff->block_duration) {
168  codec->bit_rate = codec->sample_rate * (codec->block_align << 3) /
169  aiff->block_duration;
170  }
171 
172  /* Chunk is over */
173  if (size)
174  avio_skip(pb, size);
175 
176  return num_frames;
177 }
178 
179 static int aiff_probe(AVProbeData *p)
180 {
181  /* check file header */
182  if (p->buf[0] == 'F' && p->buf[1] == 'O' &&
183  p->buf[2] == 'R' && p->buf[3] == 'M' &&
184  p->buf[8] == 'A' && p->buf[9] == 'I' &&
185  p->buf[10] == 'F' && (p->buf[11] == 'F' || p->buf[11] == 'C'))
186  return AVPROBE_SCORE_MAX;
187  else
188  return 0;
189 }
190 
191 /* aiff input */
193 {
194  int ret, size, filesize;
195  int64_t offset = 0, position;
196  uint32_t tag;
197  unsigned version = AIFF_C_VERSION1;
198  AVIOContext *pb = s->pb;
199  AVStream * st;
200  AIFFInputContext *aiff = s->priv_data;
201  ID3v2ExtraMeta *id3v2_extra_meta = NULL;
202 
203  /* check FORM header */
204  filesize = get_tag(pb, &tag);
205  if (filesize < 0 || tag != MKTAG('F', 'O', 'R', 'M'))
206  return AVERROR_INVALIDDATA;
207 
208  /* AIFF data type */
209  tag = avio_rl32(pb);
210  if (tag == MKTAG('A', 'I', 'F', 'F')) /* Got an AIFF file */
211  version = AIFF;
212  else if (tag != MKTAG('A', 'I', 'F', 'C')) /* An AIFF-C file then */
213  return AVERROR_INVALIDDATA;
214 
215  filesize -= 4;
216 
217  st = avformat_new_stream(s, NULL);
218  if (!st)
219  return AVERROR(ENOMEM);
220 
221  while (filesize > 0) {
222  /* parse different chunks */
223  size = get_tag(pb, &tag);
224  if (size < 0)
225  return size;
226 
227  filesize -= size + 8;
228 
229  switch (tag) {
230  case MKTAG('C', 'O', 'M', 'M'): /* Common chunk */
231  /* Then for the complete header info */
232  st->nb_frames = get_aiff_header(s, size, version);
233  if (st->nb_frames < 0)
234  return st->nb_frames;
235  if (offset > 0) // COMM is after SSND
236  goto got_sound;
237  break;
238  case MKTAG('I', 'D', '3', ' '):
239  position = avio_tell(pb);
240  ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
241  if (id3v2_extra_meta)
242  if ((ret = ff_id3v2_parse_apic(s, &id3v2_extra_meta)) < 0) {
243  ff_id3v2_free_extra_meta(&id3v2_extra_meta);
244  return ret;
245  }
246  ff_id3v2_free_extra_meta(&id3v2_extra_meta);
247  if (position + size > avio_tell(pb))
248  avio_skip(pb, position + size - avio_tell(pb));
249  break;
250  case MKTAG('F', 'V', 'E', 'R'): /* Version chunk */
251  version = avio_rb32(pb);
252  break;
253  case MKTAG('N', 'A', 'M', 'E'): /* Sample name chunk */
254  get_meta(s, "title" , size);
255  break;
256  case MKTAG('A', 'U', 'T', 'H'): /* Author chunk */
257  get_meta(s, "author" , size);
258  break;
259  case MKTAG('(', 'c', ')', ' '): /* Copyright chunk */
260  get_meta(s, "copyright", size);
261  break;
262  case MKTAG('A', 'N', 'N', 'O'): /* Annotation chunk */
263  get_meta(s, "comment" , size);
264  break;
265  case MKTAG('S', 'S', 'N', 'D'): /* Sampled sound chunk */
266  aiff->data_end = avio_tell(pb) + size;
267  offset = avio_rb32(pb); /* Offset of sound data */
268  avio_rb32(pb); /* BlockSize... don't care */
269  offset += avio_tell(pb); /* Compute absolute data offset */
270  if (st->codec->block_align && !pb->seekable) /* Assume COMM already parsed */
271  goto got_sound;
272  if (!pb->seekable) {
273  av_log(s, AV_LOG_ERROR, "file is not seekable\n");
274  return -1;
275  }
276  avio_skip(pb, size - 8);
277  break;
278  case MKTAG('w', 'a', 'v', 'e'):
279  if ((uint64_t)size > (1<<30))
280  return -1;
282  if (!st->codec->extradata)
283  return AVERROR(ENOMEM);
284  st->codec->extradata_size = size;
285  avio_read(pb, st->codec->extradata, size);
286  if (st->codec->codec_id == AV_CODEC_ID_QDM2 && size>=12*4 && !st->codec->block_align) {
287  st->codec->block_align = AV_RB32(st->codec->extradata+11*4);
288  aiff->block_duration = AV_RB32(st->codec->extradata+9*4);
289  }
290  break;
291  case MKTAG('C','H','A','N'):
292  if(ff_mov_read_chan(s, pb, st, size) < 0)
293  return AVERROR_INVALIDDATA;
294  break;
295  default: /* Jump */
296  if (size & 1) /* Always even aligned */
297  size++;
298  avio_skip(pb, size);
299  }
300  }
301 
302 got_sound:
303  if (!st->codec->block_align) {
304  av_log(s, AV_LOG_ERROR, "could not find COMM tag or invalid block_align value\n");
305  return -1;
306  }
307 
308  /* Now positioned, get the sound data start and end */
309  avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
310  st->start_time = 0;
311  st->duration = st->nb_frames * aiff->block_duration;
312 
313  /* Position the stream at the first block */
314  avio_seek(pb, offset, SEEK_SET);
315 
316  return 0;
317 }
318 
319 #define MAX_SIZE 4096
320 
322  AVPacket *pkt)
323 {
324  AVStream *st = s->streams[0];
325  AIFFInputContext *aiff = s->priv_data;
326  int64_t max_size;
327  int res, size;
328 
329  /* calculate size of remaining data */
330  max_size = aiff->data_end - avio_tell(s->pb);
331  if (max_size <= 0)
332  return AVERROR_EOF;
333 
334  /* Now for that packet */
335  if (st->codec->block_align >= 33) // GSM, QCLP, IMA4
336  size = st->codec->block_align;
337  else
338  size = (MAX_SIZE / st->codec->block_align) * st->codec->block_align;
339  size = FFMIN(max_size, size);
340  res = av_get_packet(s->pb, pkt, size);
341  if (res < 0)
342  return res;
343 
344  if (size >= st->codec->block_align)
345  pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
346  /* Only one stream in an AIFF file */
347  pkt->stream_index = 0;
348  pkt->duration = (res / st->codec->block_align) * aiff->block_duration;
349  return 0;
350 }
351 
353  .name = "aiff",
354  .long_name = NULL_IF_CONFIG_SMALL("Audio IFF"),
355  .priv_data_size = sizeof(AIFFInputContext),
360  .codec_tag = (const AVCodecTag* const []){ ff_codec_aiff_tags, 0 },
361 };