Create a tune with GoAudio

main.go

package main

import (
	"fmt"
	synth "github.com/DylanMeeus/GoAudio/synthesizer"
	wave "github.com/DylanMeeus/GoAudio/wave"
)

func main() {
	fmt.Println("generating sound")

	wfmt := wave.NewWaveFmt(1, 1, 44100, 16, nil)

	output := []float64{}

	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.35, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.35, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.35, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.12, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.12, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.12, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.12, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.12, wfmt.SampleRate)...)
	output = append(output, F(554.37, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.12, wfmt.SampleRate)...)
	output = append(output, F(587.33, 0.36, wfmt.SampleRate)...)
	output = append(output, F(440, 0.36, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.12, wfmt.SampleRate)...)
	output = append(output, F(440, 0.40, wfmt.SampleRate)...)

	frames := wave.FloatsToFrames(output)
	wave.WriteFrames(frames, wfmt, "adsr.wav")
	fmt.Println("done")
}

func F(freq, duration float64, sr int) []float64 {
	st := synth.NewSineTable(8 * 1024)
	losc, err := synth.NewLookupOscillator(sr, st, 0)
	if err != nil {
		panic(err)
	}

	ticks := int(duration * float64(sr))
	output := make([]float64, ticks)
	var adsrtime int
	for i := 0; i < ticks; i++ {
		value := synth.ADSR(0.9, duration, duration/10, duration/10, 0.5, duration, float64(sr), adsrtime)
		adsrtime++
		output[i] = value * losc.InterpolateTick(freq)
	}
	return output
}