Generate Wave sample

gistfile1.html

<p><script>(function(){
/*
	Generate Wave sample
*/
var time = 1.0,   // 1[sec]
sampling = 44100, // Samples per second
chan = 2,
waveLen = time * sampling * chan;

function genWave(buf)
{
	var hz = 440,//[hz]
	PI2 = 3.141592*2,
	vol = 10000,
	L = 0, R = 0, wl = waveLen;
	for (var i = 0; i < wl; ++i){
		L = R = Math.floor(vol*Math.sin(i*hz*PI2/44100.0));
		buf[2*i  ] = L;
		buf[2*i+1] = R;
	}
}
	
function createAudio()
{
	var i, wave, l1, l2, y,
	wlen = waveLen,
	wbuf = new Int32Array(wlen);

	genWave(wbuf);
	
	// Create wave header
	var sizeInt = 4;
	l1 = wlen * sizeInt - 8,
	l2 = l1 - 36;
	wave = String.fromCharCode(
		82,73,70,70,
		l1 & 255,(l1 >> 8) & 255,(l1 >> 16) & 255,l1 >> 24,
		87,65,86,69,102,109,116,32,16,0,0,0,1,0,2,0,
		68,172,0,0,16,177,2,0,4,0,16,0,100,97,116,97,
		l2 & 255,(l2 >> 8) & 255,(l2 >> 16) & 255,l2 >> 24
	);
	for (var i = 0; i < wlen; i++){
		y = wbuf[i];
		y = y < -32767 ? -32767 : (y > 32767 ? 32767 : y); // clipping
		wave += String.fromCharCode(y & 255, (y >> 8) & 255);
	}
	return new Audio("data:audio/wav;base64," + btoa(wave));
};

var audio = createAudio();
audio.play();
	
// disp time
var d = document.createElement("div");
document.body.appendChild(d);
setInterval(function(){
	d.innerHTML = "Time="+audio.currentTime;
},16);

})()</script>