libavformat/oggparsevorbis.c

   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 #include "libavutil/avstring.h"
  27 #include "libavutil/bswap.h"
  28 #include "libavcodec/get_bits.h"
  29 #include "libavcodec/bytestream.h"
  30 #include "avformat.h"
  31 #include "oggdec.h"
  32
  33 /**
  34  * VorbisComment metadata conversion mapping.
  35  * from Ogg Vorbis I format specification: comment field and header specification
  36  * http://xiph.org/vorbis/doc/v-comment.html
  37  */
  38 const AVMetadataConv ff_vorbiscomment_metadata_conv[] = {
  39     { "ARTIST"     , "author" },
  40     { "TITLE"      , "title"  },
  41     { "ALBUM"      , "album"  },
  42     { "DATE"       , "year"   },
  43     { "TRACKNUMBER", "track"  },
  44     { "GENRE"      , "genre"  },
  45     { 0 }
  46 };
  47
  48 int
  49 vorbis_comment(AVFormatContext * as, uint8_t *buf, int size)
  50 {
  51     const uint8_t *p = buf;
  52     const uint8_t *end = buf + size;
  53     unsigned n, j;
  54     int s;
  55
  56     if (size < 8) /* must have vendor_length and user_comment_list_length */
  57         return -1;
  58
  59     s = bytestream_get_le32(&p);
  60
  61     if (end - p - 4 < s || s < 0)
  62         return -1;
  63
  64     p += s;
  65
  66     n = bytestream_get_le32(&p);
  67
  68     while (end - p >= 4 && n > 0) {
  69         const char *t, *v;
  70         int tl, vl;
  71
  72         s = bytestream_get_le32(&p);
  73
  74         if (end - p < s || s < 0)
  75             break;
  76
  77         t = p;
  78         p += s;
  79         n--;
  80
  81         v = memchr(t, '=', s);
  82         if (!v)
  83             continue;
  84
  85         tl = v - t;
  86         vl = s - tl - 1;
  87         v++;
  88
  89         if (tl && vl) {
  90             char *tt, *ct;
  91
  92             tt = av_malloc(tl + 1);
  93             ct = av_malloc(vl + 1);
  94             if (!tt || !ct) {
  95                 av_freep(&tt);
  96                 av_freep(&ct);
  97                 av_log(as, AV_LOG_WARNING, "out-of-memory error. skipping VorbisComment tag.\n");
  98                 continue;
  99             }
 100
 101             for (j = 0; j < tl; j++)
 102                 tt[j] = toupper(t[j]);
 103             tt[tl] = 0;
 104
 105             memcpy(ct, v, vl);
 106             ct[vl] = 0;
 107
 108             av_metadata_set(&as->metadata, tt, ct);
 109
 110             av_freep(&tt);
 111             av_freep(&ct);
 112         }
 113     }
 114
 115     if (p != end)
 116         av_log(as, AV_LOG_INFO, "%ti bytes of comment header remain\n", end-p);
 117     if (n > 0)
 118         av_log(as, AV_LOG_INFO,
 119                "truncated comment header, %i comments not found\n", n);
 120
 121     return 0;
 122 }
 123
 124
 125 /** Parse the vorbis header
 126  * Vorbis Identification header from Vorbis_I_spec.html#vorbis-spec-codec
 127  * [vorbis_version] = read 32 bits as unsigned integer | Not used
 128  * [audio_channels] = read 8 bit integer as unsigned | Used
 129  * [audio_sample_rate] = read 32 bits as unsigned integer | Used
 130  * [bitrate_maximum] = read 32 bits as signed integer | Not used yet
 131  * [bitrate_nominal] = read 32 bits as signed integer | Not used yet
 132  * [bitrate_minimum] = read 32 bits as signed integer | Used as bitrate
 133  * [blocksize_0] = read 4 bits as unsigned integer | Not Used
 134  * [blocksize_1] = read 4 bits as unsigned integer | Not Used
 135  * [framing_flag] = read one bit | Not Used
 136  *    */
 137
 138 struct oggvorbis_private {
 139     unsigned int len[3];
 140     unsigned char *packet[3];
 141 };
 142
 143
 144 static unsigned int
 145 fixup_vorbis_headers(AVFormatContext * as, struct oggvorbis_private *priv,
 146                      uint8_t **buf)
 147 {
 148     int i,offset, len;
 149     unsigned char *ptr;
 150
 151     len = priv->len[0] + priv->len[1] + priv->len[2];
 152     ptr = *buf = av_mallocz(len + len/255 + 64);
 153
 154     ptr[0] = 2;
 155     offset = 1;
 156     offset += av_xiphlacing(&ptr[offset], priv->len[0]);
 157     offset += av_xiphlacing(&ptr[offset], priv->len[1]);
 158     for (i = 0; i < 3; i++) {
 159         memcpy(&ptr[offset], priv->packet[i], priv->len[i]);
 160         offset += priv->len[i];
 161     }
 162     *buf = av_realloc(*buf, offset + FF_INPUT_BUFFER_PADDING_SIZE);
 163     return offset;
 164 }
 165
 166
 167 static int
 168 vorbis_header (AVFormatContext * s, int idx)
 169 {
 170     struct ogg *ogg = s->priv_data;
 171     struct ogg_stream *os = ogg->streams + idx;
 172     AVStream *st = s->streams[idx];
 173     struct oggvorbis_private *priv;
 174
 175     if (os->seq > 2)
 176         return 0;
 177
 178     if (os->seq == 0) {
 179         os->private = av_mallocz(sizeof(struct oggvorbis_private));
 180         if (!os->private)
 181             return 0;
 182     }
 183
 184     if (os->psize < 1)
 185         return -1;
 186
 187     priv = os->private;
 188     priv->len[os->seq] = os->psize;
 189     priv->packet[os->seq] = av_mallocz(os->psize);
 190     memcpy(priv->packet[os->seq], os->buf + os->pstart, os->psize);
 191     if (os->buf[os->pstart] == 1) {
 192         const uint8_t *p = os->buf + os->pstart + 7; /* skip "\001vorbis" tag */
 193         unsigned blocksize, bs0, bs1;
 194
 195         if (os->psize != 30)
 196             return -1;
 197
 198         if (bytestream_get_le32(&p) != 0) /* vorbis_version */
 199             return -1;
 200
 201         st->codec->channels = bytestream_get_byte(&p);
 202         st->codec->sample_rate = bytestream_get_le32(&p);
 203         p += 4; // skip maximum bitrate
 204         st->codec->bit_rate = bytestream_get_le32(&p); // nominal bitrate
 205         p += 4; // skip minimum bitrate
 206
 207         blocksize = bytestream_get_byte(&p);
 208         bs0 = blocksize & 15;
 209         bs1 = blocksize >> 4;
 210
 211         if (bs0 > bs1)
 212             return -1;
 213         if (bs0 < 6 || bs1 > 13)
 214             return -1;
 215
 216         if (bytestream_get_byte(&p) != 1) /* framing_flag */
 217             return -1;
 218
 219         st->codec->codec_type = CODEC_TYPE_AUDIO;
 220         st->codec->codec_id = CODEC_ID_VORBIS;
 221
 222         st->time_base.num = 1;
 223         st->time_base.den = st->codec->sample_rate;
 224     } else if (os->buf[os->pstart] == 3) {
 225         if (os->psize > 8)
 226             vorbis_comment (s, os->buf + os->pstart + 7, os->psize - 8);
 227     } else {
 228         st->codec->extradata_size =
 229             fixup_vorbis_headers(s, priv, &st->codec->extradata);
 230     }
 231
 232     return os->seq < 3;
 233 }
 234
 235 const struct ogg_codec ff_vorbis_codec = {
 236     .magic = "\001vorbis",
 237     .magicsize = 7,
 238     .header = vorbis_header
 239 };