av/revid/audio_linux.go

60 lines
1.7 KiB
Go

/*
LICENSE
Copyright (C) 2019 the Australian Ocean Lab (AusOcean)
This is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
It 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 General Public License
for more details.
You should have received a copy of the GNU General Public License
in gpl.txt. If not, see http://www.gnu.org/licenses.
*/
package revid
import (
"time"
"bitbucket.org/ausocean/av/input/audio"
"bitbucket.org/ausocean/utils/logger"
)
// startAudioDevice is used to start capturing audio from an audio device and processing it.
// It returns a function that can be used to stop the device and any errors that occur.
func (r *Revid) startAudioDevice() (func() error, error) {
// Create audio device.
ac := &audio.Config{
SampleRate: r.cfg.SampleRate,
Channels: r.cfg.Channels,
RecPeriod: r.cfg.RecPeriod,
BitDepth: r.cfg.BitDepth,
Codec: r.cfg.InputCodec,
}
ai, err := audio.NewDevice(ac, r.cfg.Logger)
if err != nil {
r.cfg.Logger.Log(logger.Fatal, pkg+"failed to create audio device", "error", err.Error())
}
// Start audio device
err = ai.Start()
if err != nil {
r.cfg.Logger.Log(logger.Fatal, pkg+"failed to start audio device", "error", err.Error())
}
// Process output from audio device.
r.cfg.ChunkSize = ai.ChunkSize()
r.wg.Add(1)
go r.processFrom(ai, time.Duration(float64(time.Second)/r.cfg.WriteRate))
return func() error {
ai.Stop()
return nil
}, nil
}