Example #1
0
func main() {
	sampleRate := 44100
	blockSize := 205 * sampleRate / 8000
	window := blockSize / 4
	dt := dtmf.NewStandard(sampleRate, blockSize)
	lastKey := -1
	keyCount := 0
	samples := make([]float32, blockSize)

	if err := portaudio.Initialize(); err != nil {
		log.Fatalf("Initialize: %+v", err)
	}
	defer func() {
		if err := portaudio.Terminate(); err != nil {
			log.Fatalf("Terminate: %+v", err)
		}
	}()
	inputBuf := make([]float32, window)
	stream, err := portaudio.OpenDefaultStream(1, 0, float64(sampleRate), len(inputBuf), inputBuf)
	if err != nil {
		log.Fatalf("OpenDefaultStream: %+v", err)
	}
	defer stream.Close()
	if err := stream.Start(); err != nil {
		log.Fatalf("Start: %+v", err)
	}
	defer stream.Stop()

	fmt.Printf("%+v\n", stream.Info())

	sig := make(chan os.Signal, 1)
	signal.Notify(sig, os.Interrupt, os.Kill)
	for {
		if err := stream.Read(); err != nil {
			log.Fatalf("Read: %+v", err)
		}

		copy(samples, samples[window:])
		copy(samples[len(samples)-len(inputBuf):], inputBuf)

		if k, t := dt.Feed(samples); k == lastKey && t > 0.0 {
			keyCount++
			if keyCount == 10 {
				fmt.Printf("%c", dtmf.Keypad[k])
			}
		} else {
			lastKey = k
			keyCount = 0
		}

		select {
		case <-sig:
			fmt.Println()
			return
		default:
		}
	}
}
Example #2
0
func main() {
	sampleRate := 8000
	blockSize := 205 * sampleRate / 8000
	window := blockSize / 4
	dt := dtmf.NewStandard(sampleRate, blockSize)
	lastKey := -1
	keyCount := 0
	samples := make([]float32, blockSize)

	rd := os.Stdin
	if len(os.Args) > 1 && os.Args[1] != "-" {
		fi, err := os.Open(os.Args[1])
		if err != nil {
			log.Fatal(err)
		}
		defer fi.Close()
		rd = fi
	}

	buf := make([]byte, window*2)

	for {
		_, err := rd.Read(buf)
		if err == io.EOF {
			break
		} else if err != nil {
			log.Fatal(err)
		}

		copy(samples, samples[window:])

		si := len(samples) - window
		for i := 0; i < len(buf); i += 2 {
			s := float32(int16(buf[i])|(int16(buf[i+1])<<8)) / 32768.0
			samples[si] = s
			si++
		}

		if k, t := dt.Feed(samples); k == lastKey && t > 0.0 {
			keyCount++
			if keyCount == 9 {
				fmt.Printf("%c", dtmf.Keypad[k])
			}
		} else {
			lastKey = k
			keyCount = 0
		}
	}
	fmt.Println()
}