libavformat/oggparsespeex.c

   1 /*
   2       Copyright (C) 2008  Reimar Döffinger
   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/bswap.h"
  27 #include "libavutil/avstring.h"
  28 #include "libavcodec/get_bits.h"
  29 #include "libavcodec/bytestream.h"
  30 #include "avformat.h"
  31 #include "oggdec.h"
  32
  33 struct speex_params {
  34     int final_packet_duration;
  35 };
  36
  37 static int speex_header(AVFormatContext *s, int idx) {
  38     struct ogg *ogg = s->priv_data;
  39     struct ogg_stream *os = ogg->streams + idx;
  40     AVStream *st = s->streams[idx];
  41     uint8_t *p = os->buf + os->pstart;
  42
  43     if (os->seq > 1)
  44         return 0;
  45
  46     if (os->seq == 0) {
  47         int frames_per_packet;
  48         st->codec->codec_type = CODEC_TYPE_AUDIO;
  49         st->codec->codec_id = CODEC_ID_SPEEX;
  50
  51         st->codec->sample_rate = AV_RL32(p + 36);
  52         st->codec->channels = AV_RL32(p + 48);
  53
  54         /* We treat the whole Speex packet as a single frame everywhere Speex
  55            is handled in FFmpeg.  This avoids the complexities of splitting
  56            and joining individual Speex frames, which are not always
  57            byte-aligned. */
  58         st->codec->frame_size = AV_RL32(p + 56);
  59         frames_per_packet     = AV_RL32(p + 64);
  60         if (frames_per_packet)
  61             st->codec->frame_size *= frames_per_packet;
  62
  63         st->codec->extradata_size = os->psize;
  64         st->codec->extradata = av_malloc(st->codec->extradata_size
  65                                          + FF_INPUT_BUFFER_PADDING_SIZE);
  66         memcpy(st->codec->extradata, p, st->codec->extradata_size);
  67
  68         st->time_base.num = 1;
  69         st->time_base.den = st->codec->sample_rate;
  70     } else
  71         vorbis_comment(s, p, os->psize);
  72
  73     return 1;
  74 }
  75
  76 static int ogg_page_packets(struct ogg_stream *os)
  77 {
  78     int i;
  79     int packets = 0;
  80     for (i = 0; i < os->nsegs; i++)
  81         if (os->segments[i] < 255)
  82             packets++;
  83     return packets;
  84 }
  85
  86 static int speex_packet(AVFormatContext *s, int idx)
  87 {
  88     struct ogg *ogg = s->priv_data;
  89     struct ogg_stream *os = ogg->streams + idx;
  90     struct speex_params *spxp = os->private;
  91     int packet_size = s->streams[idx]->codec->frame_size;
  92
  93     if (!spxp) {
  94         spxp = av_mallocz(sizeof(*spxp));
  95         os->private = spxp;
  96     }
  97
  98     if (os->flags & OGG_FLAG_EOS && os->lastgp != -1 && os->granule > 0) {
  99         /* first packet of final page. we have to calculate the final packet
 100            duration here because it is the only place we know the next-to-last
 101            granule position. */
 102         spxp->final_packet_duration = os->granule - os->lastgp -
 103                                       packet_size * (ogg_page_packets(os) - 1);
 104     }
 105
 106     if (!os->lastgp && os->granule > 0)
 107         /* first packet */
 108         os->pduration = os->granule - packet_size * (ogg_page_packets(os) - 1);
 109     else if (os->flags & OGG_FLAG_EOS && os->segp == os->nsegs &&
 110              spxp->final_packet_duration)
 111         /* final packet */
 112         os->pduration = spxp->final_packet_duration;
 113     else
 114         os->pduration = packet_size;
 115
 116     return 0;
 117 }
 118
 119 const struct ogg_codec ff_speex_codec = {
 120     .magic = "Speex   ",
 121     .magicsize = 8,
 122     .header = speex_header,
 123     .packet = speex_packet
 124 };