ffmpeg/libavdevice/sndio_dec.c

109 lines
2.8 KiB
C

/*
* sndio play and grab interface
* Copyright (c) 2010 Jacob Meuser
*
* 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 <stdint.h>
#include <sndio.h>
#include "libavformat/avformat.h"
#include "sndio_common.h"
static av_cold int audio_read_header(AVFormatContext *s1,
AVFormatParameters *ap)
{
SndioData *s = s1->priv_data;
AVStream *st;
int ret;
if (ap->sample_rate <= 0 || ap->channels <= 0)
return AVERROR(EINVAL);
st = av_new_stream(s1, 0);
if (!st)
return AVERROR(ENOMEM);
s->sample_rate = ap->sample_rate;
s->channels = ap->channels;
ret = ff_sndio_open(s1, 0, s1->filename);
if (ret < 0)
return ret;
/* take real parameters */
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = s->codec_id;
st->codec->sample_rate = s->sample_rate;
st->codec->channels = s->channels;
av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
return 0;
}
static int audio_read_packet(AVFormatContext *s1, AVPacket *pkt)
{
SndioData *s = s1->priv_data;
int64_t bdelay, cur_time;
int ret;
if ((ret = av_new_packet(pkt, s->buffer_size)) < 0)
return ret;
ret = sio_read(s->hdl, pkt->data, pkt->size);
if (ret == 0 || sio_eof(s->hdl)) {
av_free_packet(pkt);
return AVERROR_EOF;
}
pkt->size = ret;
s->softpos += ret;
/* compute pts of the start of the packet */
cur_time = av_gettime();
bdelay = ret + s->hwpos - s->softpos;
/* convert to pts */
pkt->pts = cur_time - ((bdelay * 1000000) /
(s->bps * s->channels * s->sample_rate));
return 0;
}
static av_cold int audio_read_close(AVFormatContext *s1)
{
SndioData *s = s1->priv_data;
ff_sndio_close(s);
return 0;
}
AVInputFormat ff_sndio_demuxer = {
.name = "sndio",
.long_name = NULL_IF_CONFIG_SMALL("sndio audio capture"),
.priv_data_size = sizeof(SndioData),
.read_header = audio_read_header,
.read_packet = audio_read_packet,
.read_close = audio_read_close,
.flags = AVFMT_NOFILE,
};