fukuroder · December 28, 2015 12:29
diff --git a/local_wave_file_play_test.html b/local_wave_file_play_test.html
 <!DOCTYPE html>
 <html>
 <head>
 <meta charset='utf-8'>
 <title>local wave file play test</title>
 <script src='http://code.jquery.com/jquery-2.1.1.min.js'></script>
 <script>
 $(function(){
    var bufferSource;
    var gainNode;
    var decodedBuffer;

    // get AudioContext
    var context = new AudioContext();

    var decodeFinished = function(buffer){
        // set decoded buffer
        decodedBuffer = buffer;

        // enable play button and file selector
        $('#play').removeAttr('disabled');
        $('#wave').removeAttr('disabled');
    };

    var loadFinished = function(loaded_evt){
        // decode
        context.decodeAudioData(loaded_evt.target.result, decodeFinished);
    };

    $('#play')
    .attr({disabled:'disabled', value:'play'})
    .css({width:'100px'})
    .click(function(){
        if($(this).val() == 'stop'){
            //--------------
            // play -> stop
            //--------------

            // change button caption
            $(this).val('play');

            // enable file selector
            $('#wave').removeAttr('disabled');

            // stop
            bufferSource.stop(0);
        }
        else{
            //--------------
            // stop -> play
            //--------------

            // change button caption
            $(this).val('stop');

            // disable file selector
            $('#wave').attr({disabled:'disabled'})

            // generate source
            bufferSource = context.createBufferSource();
            bufferSource.buffer = decodedBuffer;

            // generate gain node
            gainNode = context.createGain();
            gainNode.gain.value = $('#gain').val()*0.01;

            // connect (source->gain->destination)
            bufferSource.connect(gainNode);
            gainNode.connect(context.destination);

            // play
            bufferSource.start(0);
        }
    });

    $('#gain')
    .attr({min:0, max:100, value:50})
    .change(function(){
        // update gain
        if(gainNode) gainNode.gain.value = $(this).val()*0.01;
    });

    $('#wave')
    .attr({accept:'audio/*'})
    .change(function(file_evt){
        // disable play button
        $('#play').attr({disabled:'disabled'});

        if(file_evt.target.files.length == 0) return;

        // disable file selector
        $(this).attr({disabled:'disabled'});

        // read local wave file
        var reader = new FileReader();
        reader.onload = loadFinished;
        reader.readAsArrayBuffer(file_evt.target.files[0]);
    });
 });
 </script>
 </head>
 <body>
 local wave file play test using Web Audio API (Google Chrome only)
 <hr/>
 <input type='button' id='play'/>
 volume:<input type='number' id='gain'/>
 <input type='file' id='wave'/>
 </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset='utf-8'>
	<title>local wave file play test</title>
	<script src='http://code.jquery.com/jquery-2.1.1.min.js'></script>
	<script>
	$(function(){
	var bufferSource;
	var gainNode;
	var decodedBuffer;

	// get AudioContext
	var context = new AudioContext();

	var decodeFinished = function(buffer){
	// set decoded buffer
	decodedBuffer = buffer;

	// enable play button and file selector
	$('#play').removeAttr('disabled');
	$('#wave').removeAttr('disabled');
	};

	var loadFinished = function(loaded_evt){
	// decode
	context.decodeAudioData(loaded_evt.target.result, decodeFinished);
	};

	$('#play')
	.attr({disabled:'disabled', value:'play'})
	.css({width:'100px'})
	.click(function(){
	if($(this).val() == 'stop'){
	//--------------
	// play -> stop
	//--------------

	// change button caption
	$(this).val('play');

	// enable file selector
	$('#wave').removeAttr('disabled');

	// stop
	bufferSource.stop(0);
	}
	else{
	//--------------
	// stop -> play
	//--------------

	// change button caption
	$(this).val('stop');

	// disable file selector
	$('#wave').attr({disabled:'disabled'})

	// generate source
	bufferSource = context.createBufferSource();
	bufferSource.buffer = decodedBuffer;

	// generate gain node
	gainNode = context.createGain();
	gainNode.gain.value = $('#gain').val()*0.01;

	// connect (source->gain->destination)
	bufferSource.connect(gainNode);
	gainNode.connect(context.destination);

	// play
	bufferSource.start(0);
	}
	});

	$('#gain')
	.attr({min:0, max:100, value:50})
	.change(function(){
	// update gain
	if(gainNode) gainNode.gain.value = $(this).val()*0.01;
	});

	$('#wave')
	.attr({accept:'audio/*'})
	.change(function(file_evt){
	// disable play button
	$('#play').attr({disabled:'disabled'});

	if(file_evt.target.files.length == 0) return;

	// disable file selector
	$(this).attr({disabled:'disabled'});

	// read local wave file
	var reader = new FileReader();
	reader.onload = loadFinished;
	reader.readAsArrayBuffer(file_evt.target.files[0]);
	});
	});
	</script>
	</head>
	<body>
	local wave file play test using Web Audio API (Google Chrome only)
	<hr/>
	<input type='button' id='play'/>
	volume:<input type='number' id='gain'/>
	<input type='file' id='wave'/>
	</body>
	</html>