2 * Xiph CELT parser for Ogg
3 * Copyright (c) 2011 Nicolas George
5 * This file is part of FFmpeg.
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.
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.
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
24 #include "libavutil/intreadwrite.h"
29 struct oggcelt_private {
30 int extra_headers_left;
33 static int celt_header(AVFormatContext *s, int idx)
35 struct ogg *ogg = s->priv_data;
36 struct ogg_stream *os = ogg->streams + idx;
37 AVStream *st = s->streams[idx];
38 struct oggcelt_private *priv = os->private;
39 uint8_t *p = os->buf + os->pstart;
41 if (os->psize == 60 &&
42 !memcmp(p, ff_celt_codec.magic, ff_celt_codec.magicsize)) {
45 uint32_t version, sample_rate, nb_channels, frame_size;
46 uint32_t overlap, extra_headers;
48 priv = av_malloc(sizeof(struct oggcelt_private));
50 return AVERROR(ENOMEM);
51 if (ff_alloc_extradata(st->codec, 2 * sizeof(uint32_t)) < 0) {
53 return AVERROR(ENOMEM);
55 version = AV_RL32(p + 28);
56 /* unused header size field skipped */
57 sample_rate = AV_RL32(p + 36);
58 nb_channels = AV_RL32(p + 40);
59 frame_size = AV_RL32(p + 44);
60 overlap = AV_RL32(p + 48);
61 /* unused bytes per packet field skipped */
62 extra_headers = AV_RL32(p + 56);
63 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
64 st->codec->codec_id = AV_CODEC_ID_CELT;
65 st->codec->sample_rate = sample_rate;
66 st->codec->channels = nb_channels;
67 st->codec->frame_size = frame_size;
69 avpriv_set_pts_info(st, 64, 1, sample_rate);
70 priv->extra_headers_left = 1 + extra_headers;
73 AV_WL32(st->codec->extradata + 0, overlap);
74 AV_WL32(st->codec->extradata + 4, version);
76 } else if (priv && priv->extra_headers_left) {
77 /* Extra headers (vorbiscomment) */
79 ff_vorbis_comment(s, &st->metadata, p, os->psize);
80 priv->extra_headers_left--;
87 const struct ogg_codec ff_celt_codec = {
90 .header = celt_header,