func (s *stream) Read(buf []byte) (int, error) {
	if len(s.remaining) > 0 {
		n := copy(buf, s.remaining)
		s.remaining = s.remaining[n:]
		return n, nil
	}

	var origBuf []byte
	if len(buf)%4 > 0 {
		origBuf = buf
		buf = make([]byte, len(origBuf)+4-len(origBuf)%4)
	}

	const length = int64(sampleRate / frequency)
	p := s.position / 4
	for i := 0; i < len(buf)/4; i++ {
		const max = 32767
		b := int16(math.Sin(2*math.Pi*float64(p)/float64(length)) * max)
		buf[4*i] = byte(b)
		buf[4*i+1] = byte(b >> 8)
		buf[4*i+2] = byte(b)
		buf[4*i+3] = byte(b >> 8)
		p++
	}

	s.position += int64(len(buf))
	s.position %= length * 4

	if origBuf != nil {
		n := copy(origBuf, buf)
		s.remaining = buf[n:]
		return n, nil
	}
	return len(buf), nil
}
func (s *stream) Read(buf []byte) (int, error) {
	if len(s.remaining) > 0 {
		n := copy(buf, s.remaining)
		s.remaining = s.remaining[n:]
		return n, nil
	}

	var origBuf []byte
	if len(buf)%4 > 0 {
		origBuf = buf
		buf = make([]byte, len(origBuf)+4-len(origBuf)%4)
	}

	const length = int64(sampleRate / frequency)
	p := s.position / 4
	for i := 0; i < len(buf)/4; i++ {
		const max = 32767
		b := int16(math.Sin(2*math.Pi*float64(p)/float64(length)) * max)
		buf[4*i] = byte(b)
		buf[4*i+1] = byte(b >> 8)
		buf[4*i+2] = byte(b)
		buf[4*i+3] = byte(b >> 8)
		p++
	}

	s.position += int64(len(buf))
	s.position %= length * 4

	if origBuf != nil {
		n := copy(origBuf, buf)
		s.remaining = buf[n:]
		return n, nil
	}
	return len(buf), nil
}
func ( s * stream ) Read ( buf [ ] byte ) ( int , error ) { if len ( s . remaining ) > 0 { n := copy ( buf , s . remaining ) s . remaining = s . remaining [ n : ] return n , nil } var origBuf [ ] byte if len ( buf ) % 4 > 0 { origBuf = buf buf = make ( [ ] byte , len ( origBuf ) + 4 - len ( origBuf ) % 4 ) } const length = int64 ( sampleRate / frequency ) p := s . position / 4 for i := 0 ; i < len ( buf ) / 4 ; i ++ { const max = 32767 b := int16 ( math . Sin ( 2 * math . Pi * float64 ( p ) / float64 ( length ) ) * max ) buf [ 4 * i ] = byte ( b ) buf [ 4 * i + 1 ] = byte ( b >> 8 ) buf [ 4 * i + 2 ] = byte ( b ) buf [ 4 * i + 3 ] = byte ( b >> 8 ) p ++ } s . position += int64 ( len ( buf ) ) s . position %= length * 4 if origBuf != nil { n := copy ( origBuf , buf ) s . remaining = buf [ n : ] return n , nil } return len ( buf ) , nil }
// Read is io.Reader's Read.
//
// Read fills the data with sine wave samples.
Read is io . Reader s Read . Read fills the data with sine wave samples .