| /* |
| * Xiph CELT parser for Ogg |
| * Copyright (c) 2011 Nicolas George |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include <string.h> |
| |
| #include "libavutil/intreadwrite.h" |
| #include "avformat.h" |
| #include "internal.h" |
| #include "oggdec.h" |
| |
| struct oggcelt_private { |
| int extra_headers_left; |
| }; |
| |
| static int celt_header(AVFormatContext *s, int idx) |
| { |
| struct ogg *ogg = s->priv_data; |
| struct ogg_stream *os = ogg->streams + idx; |
| AVStream *st = s->streams[idx]; |
| struct oggcelt_private *priv = os->private; |
| uint8_t *p = os->buf + os->pstart; |
| int ret; |
| |
| if (os->psize == 60 && |
| !memcmp(p, ff_celt_codec.magic, ff_celt_codec.magicsize)) { |
| /* Main header */ |
| |
| uint32_t version, sample_rate, nb_channels; |
| uint32_t overlap, extra_headers; |
| |
| priv = av_malloc(sizeof(struct oggcelt_private)); |
| if (!priv) |
| return AVERROR(ENOMEM); |
| ret = ff_alloc_extradata(st->codecpar, 2 * sizeof(uint32_t)); |
| if (ret < 0) { |
| av_free(priv); |
| return ret; |
| } |
| version = AV_RL32(p + 28); |
| /* unused header size field skipped */ |
| sample_rate = AV_RL32(p + 36); |
| nb_channels = AV_RL32(p + 40); |
| overlap = AV_RL32(p + 48); |
| /* unused bytes per packet field skipped */ |
| extra_headers = AV_RL32(p + 56); |
| st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codecpar->codec_id = AV_CODEC_ID_CELT; |
| st->codecpar->sample_rate = sample_rate; |
| st->codecpar->channels = nb_channels; |
| if (sample_rate) |
| avpriv_set_pts_info(st, 64, 1, sample_rate); |
| |
| if (os->private) { |
| av_free(priv); |
| priv = os->private; |
| } |
| os->private = priv; |
| priv->extra_headers_left = 1 + extra_headers; |
| |
| AV_WL32(st->codecpar->extradata + 0, overlap); |
| AV_WL32(st->codecpar->extradata + 4, version); |
| return 1; |
| } else if (priv && priv->extra_headers_left) { |
| /* Extra headers (vorbiscomment) */ |
| |
| ff_vorbis_stream_comment(s, st, p, os->psize); |
| priv->extra_headers_left--; |
| return 1; |
| } else { |
| return 0; |
| } |
| } |
| |
| const struct ogg_codec ff_celt_codec = { |
| .magic = "CELT ", |
| .magicsize = 8, |
| .header = celt_header, |
| .nb_header = 2, |
| }; |