func (so SndFileOutput) Write(sampleRate float64, channels []chan float64) (err error) {
info := sndfile.Info{
Samplerate: int32(sampleRate),
Channels: int32(len(channels)),
Format: so.Format,
}
f, err := sndfile.Open(so.Filename, sndfile.Write, &info)
if err != nil {
return err
}
defer f.Close()
for buffer := range soundio.Interlace(channels, so.BufferSize) {
_, err = f.WriteItems(buffer)
if err != nil {
return err
}
}
return nil
}
func (so Output) Write(sampleRate float64, channels []chan float64) (err error) {
handle := alsa.New()
err = handle.Open(so.Device, alsa.StreamTypePlayback, alsa.ModeBlock)
if err != nil {
return err
}
defer handle.Close()
handle.SampleFormat = alsa.SampleFormatS16LE
handle.SampleRate = int(sampleRate)
handle.Channels = len(channels)
err = handle.ApplyHwParams()
if err != nil {
return err
}
byteBuffer := make([]uint8, len(channels)*so.BufferSize*2)
for buffer := range soundio.Interlace(channels, so.BufferSize) {
for i, x := range buffer {
y := int16(x * 32767)
byteBuffer[i*2] = uint8(y)
byteBuffer[i*2+1] = uint8(y >> 8)
}
_, err = handle.Write(byteBuffer)
if err != nil {
return err
}
}
err = handle.Drain()
if err != nil {
return err
}
return nil
}