mathieu-fanduel/audiodisplay.js

## audiodisplay.js
function drawBuffer( width, height, context, data ) {
    var step = Math.ceil( data.length / width );
    var amp = height / 2;
    context.fillStyle = "silver";
    context.clearRect(0,0,width,height);
    for(var i=0; i < width; i++){
        var min = 1.0;
        var max = -1.0;
        for (j=0; j<step; j++) {
            var datum = data[(i*step)+j];
            if (datum < min)
                min = datum;
            if (datum > max)
                max = datum;
        }
        context.fillRect(i,(1+min)*amp,1,Math.max(1,(max-min)*amp));
    }
}

## index.html
<!DOCTYPE html>
<!-- saved from url=(0058)https:/webaudiodemos.appspot.com/AudioRecorder/index.html -->
<html><head><meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
	<meta name="viewport" content="width=device-width,initial-scale=1">
	<title>Audio Recorder</title>

	<script src="audiodisplay.js"></script>
	<script src="recorder.js"></script>
	<script src="main.js"></script>
	<style>
	html { overflow: hidden; }
	body {
		font: 14pt Arial, sans-serif;
		background: lightgrey;
		display: flex;
		flex-direction: column;
		height: 100vh;
		width: 100%;
		margin: 0 0;
	}
	canvas {
		display: inline-block;
		background: #202020;
		width: 95%;
		height: 95%;
		box-shadow: 0px 0px 10px blue;
	}
	#controls {
		display: flex;
		flex-direction: row;
		align-items: center;
		justify-content: space-around;
		height: 20%;
		width: 100%;
	}
	#record { height: 15vh; }
	#record.recording {
		background: red;
		background: -webkit-radial-gradient(center, ellipse cover, #ff0000 0%,lightgrey 75%,lightgrey 100%,#7db9e8 100%);
		background: -moz-radial-gradient(center, ellipse cover, #ff0000 0%,lightgrey 75%,lightgrey 100%,#7db9e8 100%);
		background: radial-gradient(center, ellipse cover, #ff0000 0%,lightgrey 75%,lightgrey 100%,#7db9e8 100%);
	}
	#save, #save img { height: 10vh; }
	#save { opacity: 0.25;}
	#save[download] { opacity: 1;}
	#viz {
		height: 80%;
		width: 100%;
		display: flex;
		flex-direction: column;
		justify-content: space-around;
		align-items: center;
	}
	@media (orientation: landscape) {
		body { flex-direction: row;}
		#controls { flex-direction: column; height: 100%; width: 10%;}
		#viz { height: 100%; width: 90%;}
	}
	#max{
		font-size: 200%;
	}

	</style>
</head>
<body>
	<div id="viz">
		<canvas id="analyser" width="1024" height="500"></canvas>
	</div>
	<div id="max"></div>

</body></html>

## main.js
/* Copyright 2013 Chris Wilson

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

window.AudioContext = window.AudioContext || window.webkitAudioContext;

var audioContext = new AudioContext();
var audioInput = null,
    realAudioInput = null,
    inputPoint = null;
var rafID = null;
var analyserContext = null;
var canvasWidth, canvasHeight;
var recIndex = 0;
console.log("audioContext.sampleRate = "+audioContext.sampleRate);


/* TODO:

- offer mono option
- "Monitor input" switch
*/


function gotBuffers( buffers ) {
    var canvas = document.getElementById( "wavedisplay" );

    console.log("LOL");
    drawBuffer( canvas.width, canvas.height, canvas.getContext('2d'), buffers[0] );
}


var maxMagnitureIndex = 0;
var maxMagnitureValue = 0;
setInterval(function(){
    document.getElementById("max").innerHTML = "Max:<br/>"+maxMagnitureValue;
  }, 1000);


function updateAnalysers(time) {
    if (!analyserContext) {
        var canvas = document.getElementById("analyser");
        canvasWidth = canvas.width;
        canvasHeight = canvas.height;
        analyserContext = canvas.getContext('2d');
    }

    // analyzer draw code here
    {
        var SPACING = 1;
        var BAR_WIDTH = 1;
        var numBars = Math.round(canvasWidth / SPACING) * 16;
        var freqByteData = new Uint8Array(analyserNode.frequencyBinCount);
        analyserNode.getByteFrequencyData(freqByteData);

        analyserContext.clearRect(0, 0, canvasWidth, canvasHeight);
        analyserContext.fillStyle = '#F6D565';
        analyserContext.lineCap = 'round';
        var multiplier = analyserNode.frequencyBinCount / numBars;
        maxMagnitureIndex = 0;
        maxMagnitureValue = 0;
        gain = 2;
        for (var i = 0; i < numBars; ++i) {
            var magnitude = 0;
            var offset = Math.floor( i * multiplier );
            // gotta sum/average the block, or we miss narrow-bandwidth spikes
            for (var j = 0; j< multiplier; j++)
                magnitude += freqByteData[offset + j];
            magnitude = magnitude / multiplier;
            magnitude = magnitude * gain;
            if(maxMagnitureValue < magnitude){
              maxMagnitureIndex = i ;
              maxMagnitureValue = magnitude;
            }
            analyserContext.fillRect(i * SPACING, canvasHeight, BAR_WIDTH, -magnitude);
        }
    }

    rafID = window.requestAnimationFrame( updateAnalysers );
}


function gotStream(stream) {
    inputPoint = audioContext.createGain();

    // Create an AudioNode from the stream.
    realAudioInput = audioContext.createMediaStreamSource(stream);
    audioInput = realAudioInput;
    audioInput.connect(inputPoint);

    analyserNode = audioContext.createAnalyser();
    analyserNode.fftSize = 1024*16;
    inputPoint.connect( analyserNode );
    zeroGain = audioContext.createGain();
    zeroGain.gain.value = 0.0;
    inputPoint.connect( zeroGain );
    zeroGain.connect( audioContext.destination );
    updateAnalysers();
}

function initAudio() {
        if (!navigator.getUserMedia)
            navigator.getUserMedia = navigator.webkitGetUserMedia || navigator.mozGetUserMedia;
        if (!navigator.cancelAnimationFrame)
            navigator.cancelAnimationFrame = navigator.webkitCancelAnimationFrame || navigator.mozCancelAnimationFrame;
        if (!navigator.requestAnimationFrame)
            navigator.requestAnimationFrame = navigator.webkitRequestAnimationFrame || navigator.mozRequestAnimationFrame;

    navigator.getUserMedia(
        {
            "audio": {
                "mandatory": {
                    "googEchoCancellation": "false",
                    "googAutoGainControl": "false",
                    "googNoiseSuppression": "false",
                    "googHighpassFilter": "false"
                },
                "optional": []
            },
        }, gotStream, function(e) {
            alert('Error getting audio');
            console.log(e);
        });
}

window.addEventListener('load', initAudio );

## sin.rb
# install
# > gem install sinatra
# Run
# > ruby sin.rb -o 0.0.0.0
# Access
# http://127.0.0.1:4567/
# http://<IP>:4567/
require 'rubygems'
require 'sinatra'
require 'json'

get '/' do
  File.read(File.join( 'index.html'))
end
	function drawBuffer( width, height, context, data ) {
	var step = Math.ceil( data.length / width );
	var amp = height / 2;
	context.fillStyle = "silver";
	context.clearRect(0,0,width,height);
	for(var i=0; i < width; i++){
	var min = 1.0;
	var max = -1.0;
	for (j=0; j<step; j++) {
	var datum = data[(i*step)+j];
	if (datum < min)
	min = datum;
	if (datum > max)
	max = datum;
	}
	context.fillRect(i,(1+min)amp,1,Math.max(1,(max-min)amp));
	}
	}
	<!DOCTYPE html>
	<!-- saved from url=(0058)https:/webaudiodemos.appspot.com/AudioRecorder/index.html -->
	<html><head><meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
	<meta name="viewport" content="width=device-width,initial-scale=1">
	<title>Audio Recorder</title>

	<script src="audiodisplay.js"></script>
	<script src="recorder.js"></script>
	<script src="main.js"></script>
	<style>
	html { overflow: hidden; }
	body {
	font: 14pt Arial, sans-serif;
	background: lightgrey;
	display: flex;
	flex-direction: column;
	height: 100vh;
	width: 100%;
	margin: 0 0;
	}
	canvas {
	display: inline-block;
	background: #202020;
	width: 95%;
	height: 95%;
	box-shadow: 0px 0px 10px blue;
	}
	#controls {
	display: flex;
	flex-direction: row;
	align-items: center;
	justify-content: space-around;
	height: 20%;
	width: 100%;
	}
	#record { height: 15vh; }
	#record.recording {
	background: red;
	background: -webkit-radial-gradient(center, ellipse cover, #ff0000 0%,lightgrey 75%,lightgrey 100%,#7db9e8 100%);
	background: -moz-radial-gradient(center, ellipse cover, #ff0000 0%,lightgrey 75%,lightgrey 100%,#7db9e8 100%);
	background: radial-gradient(center, ellipse cover, #ff0000 0%,lightgrey 75%,lightgrey 100%,#7db9e8 100%);
	}
	#save, #save img { height: 10vh; }
	#save { opacity: 0.25;}
	#save[download] { opacity: 1;}
	#viz {
	height: 80%;
	width: 100%;
	display: flex;
	flex-direction: column;
	justify-content: space-around;
	align-items: center;
	}
	@media (orientation: landscape) {
	body { flex-direction: row;}
	#controls { flex-direction: column; height: 100%; width: 10%;}
	#viz { height: 100%; width: 90%;}
	}
	#max{
	font-size: 200%;
	}

	</style>
	</head>
	<body>
	<div id="viz">
	<canvas id="analyser" width="1024" height="500"></canvas>
	</div>
	<div id="max"></div>

	</body></html>
	/* Copyright 2013 Chris Wilson

	Licensed under the Apache License, Version 2.0 (the "License");
	you may not use this file except in compliance with the License.
	You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	*/

	window.AudioContext = window.AudioContext \|\| window.webkitAudioContext;

	var audioContext = new AudioContext();
	var audioInput = null,
	realAudioInput = null,
	inputPoint = null;
	var rafID = null;
	var analyserContext = null;
	var canvasWidth, canvasHeight;
	var recIndex = 0;
	console.log("audioContext.sampleRate = "+audioContext.sampleRate);


	/* TODO:

	- offer mono option
	- "Monitor input" switch
	*/


	function gotBuffers( buffers ) {
	var canvas = document.getElementById( "wavedisplay" );

	console.log("LOL");
	drawBuffer( canvas.width, canvas.height, canvas.getContext('2d'), buffers[0] );
	}



	var maxMagnitureIndex = 0;
	var maxMagnitureValue = 0;
	setInterval(function(){
	document.getElementById("max").innerHTML = "Max:<br/>"+maxMagnitureValue;
	}, 1000);


	function updateAnalysers(time) {
	if (!analyserContext) {
	var canvas = document.getElementById("analyser");
	canvasWidth = canvas.width;
	canvasHeight = canvas.height;
	analyserContext = canvas.getContext('2d');
	}

	// analyzer draw code here
	{
	var SPACING = 1;
	var BAR_WIDTH = 1;
	var numBars = Math.round(canvasWidth / SPACING) * 16;
	var freqByteData = new Uint8Array(analyserNode.frequencyBinCount);
	analyserNode.getByteFrequencyData(freqByteData);

	analyserContext.clearRect(0, 0, canvasWidth, canvasHeight);
	analyserContext.fillStyle = '#F6D565';
	analyserContext.lineCap = 'round';
	var multiplier = analyserNode.frequencyBinCount / numBars;
	maxMagnitureIndex = 0;
	maxMagnitureValue = 0;
	gain = 2;
	for (var i = 0; i < numBars; ++i) {
	var magnitude = 0;
	var offset = Math.floor( i * multiplier );
	// gotta sum/average the block, or we miss narrow-bandwidth spikes
	for (var j = 0; j< multiplier; j++)
	magnitude += freqByteData[offset + j];
	magnitude = magnitude / multiplier;
	magnitude = magnitude * gain;
	if(maxMagnitureValue < magnitude){
	maxMagnitureIndex = i ;
	maxMagnitureValue = magnitude;
	}
	analyserContext.fillRect(i * SPACING, canvasHeight, BAR_WIDTH, -magnitude);
	}
	}

	rafID = window.requestAnimationFrame( updateAnalysers );
	}


	function gotStream(stream) {
	inputPoint = audioContext.createGain();

	// Create an AudioNode from the stream.
	realAudioInput = audioContext.createMediaStreamSource(stream);
	audioInput = realAudioInput;
	audioInput.connect(inputPoint);

	analyserNode = audioContext.createAnalyser();
	analyserNode.fftSize = 1024*16;
	inputPoint.connect( analyserNode );
	zeroGain = audioContext.createGain();
	zeroGain.gain.value = 0.0;
	inputPoint.connect( zeroGain );
	zeroGain.connect( audioContext.destination );
	updateAnalysers();
	}

	function initAudio() {
	if (!navigator.getUserMedia)
	navigator.getUserMedia = navigator.webkitGetUserMedia \|\| navigator.mozGetUserMedia;
	if (!navigator.cancelAnimationFrame)
	navigator.cancelAnimationFrame = navigator.webkitCancelAnimationFrame \|\| navigator.mozCancelAnimationFrame;
	if (!navigator.requestAnimationFrame)
	navigator.requestAnimationFrame = navigator.webkitRequestAnimationFrame \|\| navigator.mozRequestAnimationFrame;

	navigator.getUserMedia(
	{
	"audio": {
	"mandatory": {
	"googEchoCancellation": "false",
	"googAutoGainControl": "false",
	"googNoiseSuppression": "false",
	"googHighpassFilter": "false"
	},
	"optional": []
	},
	}, gotStream, function(e) {
	alert('Error getting audio');
	console.log(e);
	});
	}

	window.addEventListener('load', initAudio );
	# install
	# > gem install sinatra
	# Run
	# > ruby sin.rb -o 0.0.0.0
	# Access
	# http://127.0.0.1:4567/
	# http://<IP>:4567/
	require 'rubygems'
	require 'sinatra'
	require 'json'

	get '/' do
	File.read(File.join( 'index.html'))
	end