| 1 | /* |
| 2 | * Xiph CELT parser for Ogg |
| 3 | * Copyright (c) 2011 Nicolas George |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 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. |
| 11 | * |
| 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. |
| 16 | * |
| 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 |
| 20 | */ |
| 21 | |
| 22 | #include <string.h> |
| 23 | |
| 24 | #include "libavutil/intreadwrite.h" |
| 25 | #include "avformat.h" |
| 26 | #include "internal.h" |
| 27 | #include "oggdec.h" |
| 28 | |
| 29 | struct oggcelt_private { |
| 30 | int extra_headers_left; |
| 31 | }; |
| 32 | |
| 33 | static int celt_header(AVFormatContext *s, int idx) |
| 34 | { |
| 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; |
| 40 | |
| 41 | if (os->psize == 60 && |
| 42 | !memcmp(p, ff_celt_codec.magic, ff_celt_codec.magicsize)) { |
| 43 | /* Main header */ |
| 44 | |
| 45 | uint32_t version, sample_rate, nb_channels; |
| 46 | uint32_t overlap, extra_headers; |
| 47 | |
| 48 | priv = av_malloc(sizeof(struct oggcelt_private)); |
| 49 | if (!priv) |
| 50 | return AVERROR(ENOMEM); |
| 51 | if (ff_alloc_extradata(st->codec, 2 * sizeof(uint32_t)) < 0) { |
| 52 | av_free(priv); |
| 53 | return AVERROR(ENOMEM); |
| 54 | } |
| 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 | overlap = AV_RL32(p + 48); |
| 60 | /* unused bytes per packet field skipped */ |
| 61 | extra_headers = AV_RL32(p + 56); |
| 62 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 63 | st->codec->codec_id = AV_CODEC_ID_CELT; |
| 64 | st->codec->sample_rate = sample_rate; |
| 65 | st->codec->channels = nb_channels; |
| 66 | if (sample_rate) |
| 67 | avpriv_set_pts_info(st, 64, 1, sample_rate); |
| 68 | priv->extra_headers_left = 1 + extra_headers; |
| 69 | av_free(os->private); |
| 70 | os->private = priv; |
| 71 | AV_WL32(st->codec->extradata + 0, overlap); |
| 72 | AV_WL32(st->codec->extradata + 4, version); |
| 73 | return 1; |
| 74 | } else if (priv && priv->extra_headers_left) { |
| 75 | /* Extra headers (vorbiscomment) */ |
| 76 | |
| 77 | ff_vorbis_stream_comment(s, st, p, os->psize); |
| 78 | priv->extra_headers_left--; |
| 79 | return 1; |
| 80 | } else { |
| 81 | return 0; |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | const struct ogg_codec ff_celt_codec = { |
| 86 | .magic = "CELT ", |
| 87 | .magicsize = 8, |
| 88 | .header = celt_header, |
| 89 | .nb_header = 2, |
| 90 | }; |