Bism Allah : tests for basics of oto and mp3 loading

go.mod

@@ -0,0 +1,10 @@
+module github.com/bloeys/wavy
+
+go 1.18
+
+require (
+	github.com/hajimehoshi/go-mp3 v0.3.3
+	github.com/hajimehoshi/oto/v2 v2.1.0
+)
+
+require golang.org/x/sys v0.0.0-20220408201424-a24fb2fb8a0f // indirect

go.sum

@@ -0,0 +1,13 @@
+github.com/hajimehoshi/go-mp3 v0.3.3 h1:cWnfRdpye2m9ElSoVqneYRcpt/l3ijttgjMeQh+r+FE=
+github.com/hajimehoshi/go-mp3 v0.3.3/go.mod h1:qMJj/CSDxx6CGHiZeCgbiq2DSUkbK0UbtXShQcnfyMM=
+github.com/hajimehoshi/oto v0.6.1/go.mod h1:0QXGEkbuJRohbJaxr7ZQSxnju7hEhseiPx2hrh6raOI=
+github.com/hajimehoshi/oto/v2 v2.1.0 h1:/h+UkbKzhD7xBHOQlWgKUplBPZ+J4DK3P2Y7g2UF1X4=
+github.com/hajimehoshi/oto/v2 v2.1.0/go.mod h1:9i0oYbpJ8BhVGkXDKdXKfFthX1JUNfXjeTp944W8TGM=
+golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
+golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
+golang.org/x/mobile v0.0.0-20190415191353-3e0bab5405d6/go.mod h1:E/iHnbuqvinMTCcRqshq8CkpyQDoeVncDDYHnLhea+o=
+golang.org/x/sys v0.0.0-20190312061237-fead79001313/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190429190828-d89cdac9e872/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20220408201424-a24fb2fb8a0f h1:8w7RhxzTVgUzw/AH/9mUV5q0vMgy40SQRursCcfmkCw=
+golang.org/x/sys v0.0.0-20220408201424-a24fb2fb8a0f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

wavy.go

@@ -0,0 +1 @@
+package wavy

wavy_test.go

@@ -0,0 +1,155 @@
+package wavy_test
+
+import (
+	"io"
+	"math"
+	"os"
+	"runtime"
+	"testing"
+	"time"
+
+	"github.com/hajimehoshi/go-mp3"
+	"github.com/hajimehoshi/oto/v2"
+)
+
+const (
+	sampleRate      = 44100
+	bitDepthInBytes = 2
+	channelNum      = 2
+)
+
+//This is from the Oto example
+type SineWave struct {
+	freq   float64
+	length int64
+	pos    int64
+
+	remaining []byte
+}
+
+//Implements io.Read interface for SineWave
+func (s *SineWave) Read(buf []byte) (int, error) {
+	if len(s.remaining) > 0 {
+		n := copy(buf, s.remaining)
+		copy(s.remaining, s.remaining[n:])
+		s.remaining = s.remaining[:len(s.remaining)-n]
+		return n, nil
+	}
+
+	if s.pos == s.length {
+		return 0, io.EOF
+	}
+
+	eof := false
+	if s.pos+int64(len(buf)) > s.length {
+		buf = buf[:s.length-s.pos]
+		eof = true
+	}
+
+	var origBuf []byte
+	if len(buf)%4 > 0 {
+		origBuf = buf
+		buf = make([]byte, len(origBuf)+4-len(origBuf)%4)
+	}
+
+	length := float64(sampleRate) / float64(s.freq)
+
+	num := (bitDepthInBytes) * (channelNum)
+	p := s.pos / int64(num)
+	switch bitDepthInBytes {
+	case 1:
+		for i := 0; i < len(buf)/num; i++ {
+			const max = 127
+			b := int(math.Sin(2*math.Pi*float64(p)/length) * 0.3 * max)
+			for ch := 0; ch < channelNum; ch++ {
+				buf[num*i+ch] = byte(b + 128)
+			}
+			p++
+		}
+	case 2:
+		for i := 0; i < len(buf)/num; i++ {
+			const max = 32767
+			b := int16(math.Sin(2*math.Pi*float64(p)/length) * 0.3 * max)
+			for ch := 0; ch < channelNum; ch++ {
+				buf[num*i+2*ch] = byte(b)
+				buf[num*i+1+2*ch] = byte(b >> 8)
+			}
+			p++
+		}
+	}
+
+	s.pos += int64(len(buf))
+
+	n := len(buf)
+	if origBuf != nil {
+		n = copy(origBuf, buf)
+		s.remaining = buf[n:]
+	}
+
+	if eof {
+		return n, io.EOF
+	}
+	return n, nil
+}
+
+func NewSineWave(freq float64, duration time.Duration) *SineWave {
+	l := channelNum * bitDepthInBytes * sampleRate * int64(duration) / int64(time.Second)
+	l = l / 4 * 4
+	return &SineWave{
+		freq:   freq,
+		length: l,
+	}
+}
+
+func TestWavy(t *testing.T) {
+
+	const freqToUse = 523.3
+
+	c, ready, err := oto.NewContext(44100, 2, 2)
+	if err != nil {
+		t.Errorf("Failed to create oto context. Err: %e\n", err)
+		return
+	}
+	<-ready
+
+	playDuration := 1 * time.Second
+	player := c.NewPlayer(NewSineWave(freqToUse, playDuration))
+	player.SetVolume(0.75)
+	player.Play()
+
+	time.Sleep(playDuration)
+	runtime.KeepAlive(player)
+}
+
+func TestMP3(t *testing.T) {
+
+	audioFPath := "./test_audio_files/Fatiha.mp3"
+	f, err := os.Open(audioFPath)
+	if err != nil {
+		t.Errorf("Failed to open '%s'. Err: %s\n", audioFPath, err)
+		return
+	}
+	defer f.Close()
+
+	dec, err := mp3.NewDecoder(f)
+	if err != nil {
+		t.Errorf("Failed to decode mp3 file. Err: %s\n", err)
+		return
+	}
+
+	c, ready, err := oto.NewContext(dec.SampleRate(), 2, 2)
+	if err != nil {
+		t.Errorf("Failed to create oto context. Err: %s\n", err)
+		return
+	}
+	<-ready
+
+	player := c.NewPlayer(dec)
+	player.SetVolume(0.75)
+	player.Play()
+
+	time.Sleep(1 * time.Second)
+
+	//This is to ensure GC doesn't collect player/context. Without it no sound might play, or plays for very small amount of time.
+	runtime.KeepAlive(player)
+}