av/revid/audio_linux.go

58 lines
1.7 KiB
Go

package revid
import (
"fmt"
"strconv"
"time"
"bitbucket.org/ausocean/av/codec/codecutil"
"bitbucket.org/ausocean/av/container/mts"
"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.config.SampleRate,
Channels: r.config.Channels,
RecPeriod: r.config.RecPeriod,
BitDepth: r.config.BitDepth,
Codec: r.config.InputCodec,
}
mts.Meta.Add("sampleRate", strconv.Itoa(r.config.SampleRate))
mts.Meta.Add("channels", strconv.Itoa(r.config.Channels))
mts.Meta.Add("period", fmt.Sprintf("%.6f", r.config.RecPeriod))
mts.Meta.Add("bitDepth", strconv.Itoa(r.config.BitDepth))
switch r.config.InputCodec {
case codecutil.PCM:
mts.Meta.Add("codec", "pcm")
case codecutil.ADPCM:
mts.Meta.Add("codec", "adpcm")
default:
r.config.Logger.Log(logger.Fatal, pkg+"no audio codec set in config")
}
ai, err := audio.NewDevice(ac, r.config.Logger)
if err != nil {
r.config.Logger.Log(logger.Fatal, pkg+"failed to create audio device", "error", err.Error())
}
// Start audio device
err = ai.Start()
if err != nil {
r.config.Logger.Log(logger.Fatal, pkg+"failed to start audio device", "error", err.Error())
}
// Process output from audio device.
r.config.ChunkSize = ai.ChunkSize()
r.wg.Add(1)
go r.processFrom(ai, time.Duration(float64(time.Second)/r.config.WriteRate))
return func() error {
ai.Stop()
return nil
}, nil
}