Libav 0.7.1
libavformat/oggparsespeex.c
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00001 /*
00002       Copyright (C) 2008  Reimar Döffinger
00003 
00004       Permission is hereby granted, free of charge, to any person
00005       obtaining a copy of this software and associated documentation
00006       files (the "Software"), to deal in the Software without
00007       restriction, including without limitation the rights to use, copy,
00008       modify, merge, publish, distribute, sublicense, and/or sell copies
00009       of the Software, and to permit persons to whom the Software is
00010       furnished to do so, subject to the following conditions:
00011 
00012       The above copyright notice and this permission notice shall be
00013       included in all copies or substantial portions of the Software.
00014 
00015       THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00016       EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00017       MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00018       NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
00019       HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
00020       WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00021       OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
00022       DEALINGS IN THE SOFTWARE.
00023 **/
00024 
00025 #include <stdlib.h>
00026 #include "libavutil/bswap.h"
00027 #include "libavutil/avstring.h"
00028 #include "libavcodec/get_bits.h"
00029 #include "libavcodec/bytestream.h"
00030 #include "avformat.h"
00031 #include "oggdec.h"
00032 
00033 struct speex_params {
00034     int final_packet_duration;
00035     int seq;
00036 };
00037 
00038 static int speex_header(AVFormatContext *s, int idx) {
00039     struct ogg *ogg = s->priv_data;
00040     struct ogg_stream *os = ogg->streams + idx;
00041     struct speex_params *spxp = os->private;
00042     AVStream *st = s->streams[idx];
00043     uint8_t *p = os->buf + os->pstart;
00044 
00045     if (!spxp) {
00046         spxp = av_mallocz(sizeof(*spxp));
00047         os->private = spxp;
00048     }
00049 
00050     if (spxp->seq > 1)
00051         return 0;
00052 
00053     if (spxp->seq == 0) {
00054         int frames_per_packet;
00055         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00056         st->codec->codec_id = CODEC_ID_SPEEX;
00057 
00058         st->codec->sample_rate = AV_RL32(p + 36);
00059         st->codec->channels = AV_RL32(p + 48);
00060 
00061         /* We treat the whole Speex packet as a single frame everywhere Speex
00062            is handled in Libav.  This avoids the complexities of splitting
00063            and joining individual Speex frames, which are not always
00064            byte-aligned. */
00065         st->codec->frame_size = AV_RL32(p + 56);
00066         frames_per_packet     = AV_RL32(p + 64);
00067         if (frames_per_packet)
00068             st->codec->frame_size *= frames_per_packet;
00069 
00070         st->codec->extradata_size = os->psize;
00071         st->codec->extradata = av_malloc(st->codec->extradata_size
00072                                          + FF_INPUT_BUFFER_PADDING_SIZE);
00073         memcpy(st->codec->extradata, p, st->codec->extradata_size);
00074 
00075         av_set_pts_info(st, 64, 1, st->codec->sample_rate);
00076     } else
00077         ff_vorbis_comment(s, &st->metadata, p, os->psize);
00078 
00079     spxp->seq++;
00080     return 1;
00081 }
00082 
00083 static int ogg_page_packets(struct ogg_stream *os)
00084 {
00085     int i;
00086     int packets = 0;
00087     for (i = 0; i < os->nsegs; i++)
00088         if (os->segments[i] < 255)
00089             packets++;
00090     return packets;
00091 }
00092 
00093 static int speex_packet(AVFormatContext *s, int idx)
00094 {
00095     struct ogg *ogg = s->priv_data;
00096     struct ogg_stream *os = ogg->streams + idx;
00097     struct speex_params *spxp = os->private;
00098     int packet_size = s->streams[idx]->codec->frame_size;
00099 
00100     if (os->flags & OGG_FLAG_EOS && os->lastpts != AV_NOPTS_VALUE &&
00101         os->granule > 0) {
00102         /* first packet of final page. we have to calculate the final packet
00103            duration here because it is the only place we know the next-to-last
00104            granule position. */
00105         spxp->final_packet_duration = os->granule - os->lastpts -
00106                                       packet_size * (ogg_page_packets(os) - 1);
00107     }
00108 
00109     if (!os->lastpts && os->granule > 0)
00110         /* first packet */
00111         os->pduration = os->granule - packet_size * (ogg_page_packets(os) - 1);
00112     else if (os->flags & OGG_FLAG_EOS && os->segp == os->nsegs &&
00113              spxp->final_packet_duration)
00114         /* final packet */
00115         os->pduration = spxp->final_packet_duration;
00116     else
00117         os->pduration = packet_size;
00118 
00119     return 0;
00120 }
00121 
00122 const struct ogg_codec ff_speex_codec = {
00123     .magic = "Speex   ",
00124     .magicsize = 8,
00125     .header = speex_header,
00126     .packet = speex_packet
00127 };