func newStereoSine(freqL, freqR, sampleRate float64) *stereoSine {
s := &stereoSine{nil, freqL / sampleRate, 0, freqR / sampleRate, 0}
var err error
s.Stream, err = portaudio.OpenDefaultStream(0, 2, sampleRate, 0, s.processAudio)
chk(err)
return s
}
func main() {
if len(os.Args) < 2 {
fmt.Println("missing required argument: input file name")
return
}
fmt.Println("Playing. Press Ctrl-C to stop.")
sig := make(chan os.Signal, 1)
signal.Notify(sig, os.Interrupt, os.Kill)
fileName := os.Args[1]
f, err := os.Open(fileName)
chk(err)
defer f.Close()
id, data, err := readChunk(f)
chk(err)
if id.String() != "FORM" {
fmt.Println("bad file format")
return
}
_, err = data.Read(id[:])
chk(err)
if id.String() != "AIFF" {
fmt.Println("bad file format")
return
}
var c commonChunk
var audio io.Reader
for {
id, chunk, err := readChunk(data)
if err == io.EOF {
break
}
chk(err)
switch id.String() {
case "COMM":
chk(binary.Read(chunk, binary.BigEndian, &c))
case "SSND":
chunk.Seek(8, 1) //ignore offset and block
audio = chunk
default:
fmt.Printf("ignoring unknown chunk '%s'\n", id)
}
}
//assume 44100 sample rate, mono, 32 bit
portaudio.Initialize()
defer portaudio.Terminate()
out := make([]int32, 8192)
stream, err := portaudio.OpenDefaultStream(0, 1, 44100, len(out), &out)
chk(err)
defer stream.Close()
chk(stream.Start())
defer stream.Stop()
for remaining := int(c.NumSamples); remaining > 0; remaining -= len(out) {
if len(out) > remaining {
out = out[:remaining]
}
err := binary.Read(audio, binary.BigEndian, out)
if err == io.EOF {
break
}
chk(err)
chk(stream.Write())
select {
case <-sig:
return
default:
}
}
}
func main() {
if len(os.Args) < 2 {
fmt.Println("missing required argument: output file name")
return
}
fmt.Println("Recording. Press Ctrl-C to stop.")
sig := make(chan os.Signal, 1)
signal.Notify(sig, os.Interrupt, os.Kill)
fileName := os.Args[1]
if !strings.HasSuffix(fileName, ".aiff") {
fileName += ".aiff"
}
f, err := os.Create(fileName)
chk(err)
// form chunk
_, err = f.WriteString("FORM")
chk(err)
chk(binary.Write(f, binary.BigEndian, int32(0))) //total bytes
_, err = f.WriteString("AIFF")
chk(err)
// common chunk
_, err = f.WriteString("COMM")
chk(err)
chk(binary.Write(f, binary.BigEndian, int32(18))) //size
chk(binary.Write(f, binary.BigEndian, int16(1))) //channels
chk(binary.Write(f, binary.BigEndian, int32(0))) //number of samples
chk(binary.Write(f, binary.BigEndian, int16(32))) //bits per sample
_, err = f.Write([]byte{0x40, 0x0e, 0xac, 0x44, 0, 0, 0, 0, 0, 0}) //80-bit sample rate 44100
chk(err)
// sound chunk
_, err = f.WriteString("SSND")
chk(err)
chk(binary.Write(f, binary.BigEndian, int32(0))) //size
chk(binary.Write(f, binary.BigEndian, int32(0))) //offset
chk(binary.Write(f, binary.BigEndian, int32(0))) //block
nSamples := 0
defer func() {
// fill in missing sizes
totalBytes := 4 + 8 + 18 + 8 + 8 + 4*nSamples
_, err = f.Seek(4, 0)
chk(err)
chk(binary.Write(f, binary.BigEndian, int32(totalBytes)))
_, err = f.Seek(22, 0)
chk(err)
chk(binary.Write(f, binary.BigEndian, int32(nSamples)))
_, err = f.Seek(42, 0)
chk(err)
chk(binary.Write(f, binary.BigEndian, int32(4*nSamples+8)))
chk(f.Close())
}()
portaudio.Initialize()
defer portaudio.Terminate()
in := make([]int32, 64)
stream, err := portaudio.OpenDefaultStream(1, 0, 44100, len(in), in)
chk(err)
defer stream.Close()
chk(stream.Start())
for {
chk(stream.Read())
chk(binary.Write(f, binary.BigEndian, in))
nSamples += len(in)
select {
case <-sig:
return
default:
}
}
chk(stream.Stop())
}
