diff options
| author | Tim Redfern <tim@eclectronics.org> | 2013-08-26 15:10:18 +0100 |
|---|---|---|
| committer | Tim Redfern <tim@eclectronics.org> | 2013-08-26 15:10:18 +0100 |
| commit | 150c9823e71a161e97003849cf8b2f55b21520bd (patch) | |
| tree | 3559c840cf403d1386708b2591d58f928c7b160d /ffmpeg1/libavformat/gsmdec.c | |
| parent | b4b1e2630c95d5e6014463f7608d59dc2322a3b8 (diff) | |
adding ffmpeg specific version
Diffstat (limited to 'ffmpeg1/libavformat/gsmdec.c')
| -rw-r--r-- | ffmpeg1/libavformat/gsmdec.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/ffmpeg1/libavformat/gsmdec.c b/ffmpeg1/libavformat/gsmdec.c new file mode 100644 index 0000000..9899266 --- /dev/null +++ b/ffmpeg1/libavformat/gsmdec.c @@ -0,0 +1,100 @@ +/* + * RAW GSM demuxer + * Copyright (c) 2011 Justin Ruggles + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "libavutil/channel_layout.h" +#include "libavutil/mathematics.h" +#include "libavutil/opt.h" +#include "avformat.h" +#include "internal.h" + +#define GSM_BLOCK_SIZE 33 +#define GSM_BLOCK_SAMPLES 160 +#define GSM_SAMPLE_RATE 8000 + +typedef struct { + AVClass *class; + int sample_rate; +} GSMDemuxerContext; + +static int gsm_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + int ret, size; + + size = GSM_BLOCK_SIZE; + + pkt->pos = avio_tell(s->pb); + pkt->stream_index = 0; + + ret = av_get_packet(s->pb, pkt, size); + if (ret < GSM_BLOCK_SIZE) { + av_free_packet(pkt); + return ret < 0 ? ret : AVERROR(EIO); + } + pkt->duration = 1; + pkt->pts = pkt->pos / GSM_BLOCK_SIZE; + + return 0; +} + +static int gsm_read_header(AVFormatContext *s) +{ + GSMDemuxerContext *c = s->priv_data; + AVStream *st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + + st->codec->codec_type = AVMEDIA_TYPE_AUDIO; + st->codec->codec_id = s->iformat->raw_codec_id; + st->codec->channels = 1; + st->codec->channel_layout = AV_CH_LAYOUT_MONO; + st->codec->sample_rate = c->sample_rate; + st->codec->bit_rate = GSM_BLOCK_SIZE * 8 * c->sample_rate / GSM_BLOCK_SAMPLES; + + avpriv_set_pts_info(st, 64, GSM_BLOCK_SAMPLES, GSM_SAMPLE_RATE); + + return 0; +} + +static const AVOption options[] = { + { "sample_rate", "", offsetof(GSMDemuxerContext, sample_rate), + AV_OPT_TYPE_INT, {.i64 = GSM_SAMPLE_RATE}, 1, INT_MAX / GSM_BLOCK_SIZE, + AV_OPT_FLAG_DECODING_PARAM }, + { NULL }, +}; + +static const AVClass class = { + .class_name = "gsm demuxer", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_gsm_demuxer = { + .name = "gsm", + .long_name = NULL_IF_CONFIG_SMALL("raw GSM"), + .priv_data_size = sizeof(GSMDemuxerContext), + .read_header = gsm_read_header, + .read_packet = gsm_read_packet, + .flags = AVFMT_GENERIC_INDEX, + .extensions = "gsm", + .raw_codec_id = AV_CODEC_ID_GSM, + .priv_class = &class, +}; |
