Libav
oggparsevorbis.c
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1 /*
2  * Copyright (C) 2005 Michael Ahlberg, Måns Rullgård
3  *
4  * Permission is hereby granted, free of charge, to any person
5  * obtaining a copy of this software and associated documentation
6  * files (the "Software"), to deal in the Software without
7  * restriction, including without limitation the rights to use, copy,
8  * modify, merge, publish, distribute, sublicense, and/or sell copies
9  * of the Software, and to permit persons to whom the Software is
10  * furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be
13  * included in all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
19  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  */
24 
25 #include <stdlib.h>
26 
27 #include "libavutil/avstring.h"
28 #include "libavutil/base64.h"
29 #include "libavutil/bswap.h"
30 #include "libavutil/dict.h"
31 #include "libavcodec/bytestream.h"
32 #include "libavcodec/get_bits.h"
34 #include "avformat.h"
35 #include "flac_picture.h"
36 #include "internal.h"
37 #include "oggdec.h"
38 #include "vorbiscomment.h"
39 
40 static int ogm_chapter(AVFormatContext *as, uint8_t *key, uint8_t *val)
41 {
42  int i, cnum, h, m, s, ms, keylen = strlen(key);
43  AVChapter *chapter = NULL;
44 
45  if (keylen < 9 || sscanf(key, "CHAPTER%03d", &cnum) != 1)
46  return 0;
47 
48  if (keylen <= 10) {
49  if (sscanf(val, "%02d:%02d:%02d.%03d", &h, &m, &s, &ms) < 4)
50  return 0;
51 
52  avpriv_new_chapter(as, cnum, (AVRational) { 1, 1000 },
53  ms + 1000 * (s + 60 * (m + 60 * h)),
55  av_free(val);
56  } else if (!strcmp(key + keylen - 4, "NAME")) {
57  for (i = 0; i < as->nb_chapters; i++)
58  if (as->chapters[i]->id == cnum) {
59  chapter = as->chapters[i];
60  break;
61  }
62  if (!chapter)
63  return 0;
64 
65  av_dict_set(&chapter->metadata, "title", val, AV_DICT_DONT_STRDUP_VAL);
66  } else
67  return 0;
68 
69  av_free(key);
70  return 1;
71 }
72 
74  const uint8_t *buf, int size)
75 {
76  const uint8_t *p = buf;
77  const uint8_t *end = buf + size;
78  unsigned n, j;
79  int s;
80 
81  /* must have vendor_length and user_comment_list_length */
82  if (size < 8)
83  return AVERROR_INVALIDDATA;
84 
85  s = bytestream_get_le32(&p);
86 
87  if (end - p - 4 < s || s < 0)
88  return AVERROR_INVALIDDATA;
89 
90  p += s;
91 
92  n = bytestream_get_le32(&p);
93 
94  while (end - p >= 4 && n > 0) {
95  const char *t, *v;
96  int tl, vl;
97 
98  s = bytestream_get_le32(&p);
99 
100  if (end - p < s || s < 0)
101  break;
102 
103  t = p;
104  p += s;
105  n--;
106 
107  v = memchr(t, '=', s);
108  if (!v)
109  continue;
110 
111  tl = v - t;
112  vl = s - tl - 1;
113  v++;
114 
115  if (tl && vl) {
116  char *tt, *ct;
117 
118  tt = av_malloc(tl + 1);
119  ct = av_malloc(vl + 1);
120  if (!tt || !ct) {
121  av_freep(&tt);
122  av_freep(&ct);
123  return AVERROR(ENOMEM);
124  }
125 
126  for (j = 0; j < tl; j++)
127  tt[j] = av_toupper(t[j]);
128  tt[tl] = 0;
129 
130  memcpy(ct, v, vl);
131  ct[vl] = 0;
132 
133  /* The format in which the pictures are stored is the FLAC format.
134  * Xiph says: "The binary FLAC picture structure is base64 encoded
135  * and placed within a VorbisComment with the tag name
136  * 'METADATA_BLOCK_PICTURE'. This is the preferred and
137  * recommended way of embedding cover art within VorbisComments."
138  */
139  if (!strcmp(tt, "METADATA_BLOCK_PICTURE")) {
140  int ret;
141  char *pict = av_malloc(vl);
142 
143  if (!pict) {
144  av_freep(&tt);
145  av_freep(&ct);
146  return AVERROR(ENOMEM);
147  }
148  if ((ret = av_base64_decode(pict, ct, vl)) > 0)
149  ret = ff_flac_parse_picture(as, pict, ret);
150  av_freep(&tt);
151  av_freep(&ct);
152  av_freep(&pict);
153  if (ret < 0) {
154  av_log(as, AV_LOG_WARNING, "Failed to parse cover art block.\n");
155  continue;
156  }
157  } else if (!ogm_chapter(as, tt, ct))
158  av_dict_set(m, tt, ct,
161  }
162  }
163 
164  if (p != end)
165  av_log(as, AV_LOG_INFO,
166  "%ti bytes of comment header remain\n", end - p);
167  if (n > 0)
168  av_log(as, AV_LOG_INFO,
169  "truncated comment header, %i comments not found\n", n);
170 
172 
173  return 0;
174 }
175 
176 /*
177  * Parse the vorbis header
178  *
179  * Vorbis Identification header from Vorbis_I_spec.html#vorbis-spec-codec
180  * [vorbis_version] = read 32 bits as unsigned integer | Not used
181  * [audio_channels] = read 8 bit integer as unsigned | Used
182  * [audio_sample_rate] = read 32 bits as unsigned integer | Used
183  * [bitrate_maximum] = read 32 bits as signed integer | Not used yet
184  * [bitrate_nominal] = read 32 bits as signed integer | Not used yet
185  * [bitrate_minimum] = read 32 bits as signed integer | Used as bitrate
186  * [blocksize_0] = read 4 bits as unsigned integer | Not Used
187  * [blocksize_1] = read 4 bits as unsigned integer | Not Used
188  * [framing_flag] = read one bit | Not Used
189  */
190 
192  unsigned int len[3];
193  unsigned char *packet[3];
195  int64_t final_pts;
197 };
198 
200  struct oggvorbis_private *priv,
201  uint8_t **buf)
202 {
203  int i, offset, len, err;
204  unsigned char *ptr;
205 
206  len = priv->len[0] + priv->len[1] + priv->len[2];
207  ptr = *buf = av_mallocz(len + len / 255 + 64);
208  if (!ptr)
209  return AVERROR(ENOMEM);
210 
211  ptr[0] = 2;
212  offset = 1;
213  offset += av_xiphlacing(&ptr[offset], priv->len[0]);
214  offset += av_xiphlacing(&ptr[offset], priv->len[1]);
215  for (i = 0; i < 3; i++) {
216  memcpy(&ptr[offset], priv->packet[i], priv->len[i]);
217  offset += priv->len[i];
218  av_freep(&priv->packet[i]);
219  }
220  if ((err = av_reallocp(buf, offset + FF_INPUT_BUFFER_PADDING_SIZE)) < 0)
221  return err;
222  return offset;
223 }
224 
225 static void vorbis_cleanup(AVFormatContext *s, int idx)
226 {
227  struct ogg *ogg = s->priv_data;
228  struct ogg_stream *os = ogg->streams + idx;
229  struct oggvorbis_private *priv = os->private;
230  int i;
231  if (os->private)
232  for (i = 0; i < 3; i++)
233  av_freep(&priv->packet[i]);
234 }
235 
236 static int vorbis_header(AVFormatContext *s, int idx)
237 {
238  struct ogg *ogg = s->priv_data;
239  AVStream *st = s->streams[idx];
240  struct ogg_stream *os = ogg->streams + idx;
241  struct oggvorbis_private *priv;
242  int pkt_type = os->buf[os->pstart];
243 
244  if (!os->private) {
245  os->private = av_mallocz(sizeof(struct oggvorbis_private));
246  if (!os->private)
247  return AVERROR(ENOMEM);
248  }
249 
250  if (!(pkt_type & 1))
251  return 0;
252 
253  if (os->psize < 1 || pkt_type > 5)
254  return AVERROR_INVALIDDATA;
255 
256  priv = os->private;
257 
258  if (priv->packet[pkt_type >> 1])
259  return AVERROR_INVALIDDATA;
260  if (pkt_type > 1 && !priv->packet[0] || pkt_type > 3 && !priv->packet[1])
261  return AVERROR_INVALIDDATA;
262 
263  priv->len[pkt_type >> 1] = os->psize;
264  priv->packet[pkt_type >> 1] = av_mallocz(os->psize);
265  if (!priv->packet[pkt_type >> 1])
266  return AVERROR(ENOMEM);
267  memcpy(priv->packet[pkt_type >> 1], os->buf + os->pstart, os->psize);
268  if (os->buf[os->pstart] == 1) {
269  const uint8_t *p = os->buf + os->pstart + 7; /* skip "\001vorbis" tag */
270  unsigned blocksize, bs0, bs1;
271  int srate;
272 
273  if (os->psize != 30)
274  return AVERROR_INVALIDDATA;
275 
276  if (bytestream_get_le32(&p) != 0) /* vorbis_version */
277  return AVERROR_INVALIDDATA;
278 
279  st->codec->channels = bytestream_get_byte(&p);
280  srate = bytestream_get_le32(&p);
281  p += 4; // skip maximum bitrate
282  st->codec->bit_rate = bytestream_get_le32(&p); // nominal bitrate
283  p += 4; // skip minimum bitrate
284 
285  blocksize = bytestream_get_byte(&p);
286  bs0 = blocksize & 15;
287  bs1 = blocksize >> 4;
288 
289  if (bs0 > bs1)
290  return AVERROR_INVALIDDATA;
291  if (bs0 < 6 || bs1 > 13)
292  return AVERROR_INVALIDDATA;
293 
294  if (bytestream_get_byte(&p) != 1) /* framing_flag */
295  return AVERROR_INVALIDDATA;
296 
299 
300  if (srate > 0) {
301  st->codec->sample_rate = srate;
302  avpriv_set_pts_info(st, 64, 1, srate);
303  }
304  } else if (os->buf[os->pstart] == 3) {
305  if (os->psize > 8 &&
306  ff_vorbis_comment(s, &st->metadata, os->buf + os->pstart + 7,
307  os->psize - 8) >= 0) {
308  // drop all metadata we parsed and which is not required by libvorbis
309  unsigned new_len = 7 + 4 + AV_RL32(priv->packet[1] + 7) + 4 + 1;
310  if (new_len >= 16 && new_len < os->psize) {
311  AV_WL32(priv->packet[1] + new_len - 5, 0);
312  priv->packet[1][new_len - 1] = 1;
313  priv->len[1] = new_len;
314  }
315  }
316  } else {
317  int ret = fixup_vorbis_headers(s, priv, &st->codec->extradata);
318  if (ret < 0) {
319  st->codec->extradata_size = 0;
320  return ret;
321  }
322  st->codec->extradata_size = ret;
323  if ((ret = avpriv_vorbis_parse_extradata(st->codec, &priv->vp))) {
324  av_freep(&st->codec->extradata);
325  st->codec->extradata_size = 0;
326  return ret;
327  }
328  }
329 
330  return 1;
331 }
332 
333 static int vorbis_packet(AVFormatContext *s, int idx)
334 {
335  struct ogg *ogg = s->priv_data;
336  struct ogg_stream *os = ogg->streams + idx;
337  struct oggvorbis_private *priv = os->private;
338  int duration;
339 
340  /* first packet handling
341  * here we parse the duration of each packet in the first page and compare
342  * the total duration to the page granule to find the encoder delay and
343  * set the first timestamp */
344  if (!os->lastpts) {
345  int seg;
346  uint8_t *last_pkt = os->buf + os->pstart;
347  uint8_t *next_pkt = last_pkt;
348  int first_duration = 0;
349 
351  duration = 0;
352  for (seg = 0; seg < os->nsegs; seg++) {
353  if (os->segments[seg] < 255) {
354  int d = avpriv_vorbis_parse_frame(&priv->vp, last_pkt, 1);
355  if (d < 0) {
356  duration = os->granule;
357  break;
358  }
359  if (!duration)
360  first_duration = d;
361  duration += d;
362  last_pkt = next_pkt + os->segments[seg];
363  }
364  next_pkt += os->segments[seg];
365  }
366  os->lastpts =
367  os->lastdts = os->granule - duration;
368  s->streams[idx]->start_time = os->lastpts + first_duration;
369  if (s->streams[idx]->duration)
370  s->streams[idx]->duration -= s->streams[idx]->start_time;
371  s->streams[idx]->cur_dts = AV_NOPTS_VALUE;
372  priv->final_pts = AV_NOPTS_VALUE;
374  }
375 
376  /* parse packet duration */
377  if (os->psize > 0) {
378  duration = avpriv_vorbis_parse_frame(&priv->vp, os->buf + os->pstart, 1);
379  if (duration <= 0) {
381  return 0;
382  }
383  os->pduration = duration;
384  }
385 
386  /* final packet handling
387  * here we save the pts of the first packet in the final page, sum up all
388  * packet durations in the final page except for the last one, and compare
389  * to the page granule to find the duration of the final packet */
390  if (os->flags & OGG_FLAG_EOS) {
391  if (os->lastpts != AV_NOPTS_VALUE) {
392  priv->final_pts = os->lastpts;
393  priv->final_duration = 0;
394  }
395  if (os->segp == os->nsegs)
396  os->pduration = os->granule - priv->final_pts - priv->final_duration;
397  priv->final_duration += os->pduration;
398  }
399 
400  return 0;
401 }
402 
403 const struct ogg_codec ff_vorbis_codec = {
404  .magic = "\001vorbis",
405  .magicsize = 7,
406  .header = vorbis_header,
407  .packet = vorbis_packet,
408  .cleanup = vorbis_cleanup,
409  .nb_header = 3,
410 };
unsigned int nb_chapters
Number of chapters in AVChapter array.
Definition: avformat.h:1053
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
static int vorbis_header(AVFormatContext *s, int idx)
int size
VorbisParseContext vp
Copyright (C) 2005 Michael Ahlberg, Måns Rullgård.
Definition: oggdec.h:31
unsigned int pflags
Definition: oggdec.h:67
int avpriv_vorbis_parse_frame(VorbisParseContext *s, const uint8_t *buf, int buf_size)
Get the duration for a Vorbis packet.
int ff_vorbis_comment(AVFormatContext *as, AVDictionary **m, const uint8_t *buf, int size)
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
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:3208
static int fixup_vorbis_headers(AVFormatContext *as, struct oggvorbis_private *priv, uint8_t **buf)
void avpriv_vorbis_parse_reset(VorbisParseContext *s)
int flags
Definition: oggdec.h:76
AVDictionary * metadata
Definition: avformat.h:858
unsigned char * packet[3]
static int64_t duration
Definition: avplay.c:246
int64_t lastpts
Definition: oggdec.h:72
#define AV_DICT_DONT_STRDUP_KEY
Take ownership of a key that's been allocated with av_malloc() and children.
Definition: dict.h:63
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:198
AVChapter * avpriv_new_chapter(AVFormatContext *s, int id, AVRational time_base, int64_t start, int64_t end, const char *title)
Add a new chapter.
Definition: utils.c:2734
Format I/O context.
Definition: avformat.h:871
unsigned int psize
Definition: oggdec.h:66
int64_t cur_dts
Definition: avformat.h:800
Public dictionary API.
uint8_t
int id
unique ID to identify the chapter
Definition: avformat.h:855
#define AV_WL32(p, d)
Definition: intreadwrite.h:255
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1162
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:935
Vorbis audio parser.
int av_reallocp(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:140
bitstream reader API header.
static float t
Definition: output.c:52
static void vorbis_cleanup(AVFormatContext *s, int idx)
const AVMetadataConv ff_vorbiscomment_metadata_conv[]
VorbisComment metadata conversion mapping.
Definition: vorbiscomment.c:33
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
#define AVERROR(e)
Definition: error.h:43
#define OGG_FLAG_EOS
Definition: oggdec.h:106
AVChapter ** chapters
Definition: avformat.h:1054
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:148
uint8_t segments[255]
Definition: oggdec.h:80
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:702
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:509
int bit_rate
the average bitrate
Definition: avcodec.h:1112
uint64_t granule
Definition: oggdec.h:70
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() and chilren.
Definition: dict.h:66
unsigned int pstart
Definition: oggdec.h:65
struct ogg_stream * streams
Definition: oggdec.h:97
int segp
Definition: oggdec.h:79
static int ogm_chapter(AVFormatContext *as, uint8_t *key, uint8_t *val)
int ff_flac_parse_picture(AVFormatContext *s, uint8_t *buf, int buf_size)
Definition: flac_picture.c:26
#define AV_RL32
Definition: intreadwrite.h:146
AVDictionary * metadata
Definition: avformat.h:749
Stream structure.
Definition: avformat.h:683
NULL
Definition: eval.c:55
#define AV_LOG_INFO
Standard information.
Definition: log.h:134
enum AVMediaType codec_type
Definition: avcodec.h:1062
unsigned int pduration
Definition: oggdec.h:68
int nsegs
Definition: oggdec.h:79
enum AVCodecID codec_id
Definition: avcodec.h:1065
unsigned int len[3]
int sample_rate
samples per second
Definition: avcodec.h:1779
int extradata_size
Definition: avcodec.h:1163
void * private
Definition: oggdec.h:85
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:62
unsigned int av_xiphlacing(unsigned char *s, unsigned int v)
Encode extradata length to a buffer.
Definition: utils.c:2111
rational number numerator/denominator
Definition: rational.h:43
byte swapping routines
int64_t lastdts
Definition: oggdec.h:73
const int8_t * magic
Definition: oggdec.h:32
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:734
static int av_toupper(int c)
Locale-independent conversion of ASCII characters to uppercase.
Definition: avstring.h:172
uint8_t * buf
Definition: oggdec.h:62
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream, in stream time base.
Definition: avformat.h:727
static int vorbis_packet(AVFormatContext *s, int idx)
#define AV_PKT_FLAG_CORRUPT
The packet content is corrupted.
Definition: avcodec.h:1024
void ff_metadata_conv(AVDictionary **pm, const AVMetadataConv *d_conv, const AVMetadataConv *s_conv)
Definition: metadata.c:26
Definition: oggdec.h:96
int len
int channels
number of audio channels
Definition: avcodec.h:1780
void * priv_data
Format private data.
Definition: avformat.h:899
const struct ogg_codec ff_vorbis_codec
int av_base64_decode(uint8_t *out, const char *in, int out_size)
Decode a base64-encoded string.
Definition: base64.c:45
int avpriv_vorbis_parse_extradata(AVCodecContext *avctx, VorbisParseContext *s)
Initialize the Vorbis parser using headers in the extradata.
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:205
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:228