Prototyping 19 November 2012

The origin and theory of the cut-up, annotated audio, essay on ubuweb.

Shuffle

Javascript doesn't include a built-in function to shuffle an array, but there are lots of "recipes" to do it.

For instance: http://stackoverflow.com/questions/6274339/how-can-i-shuffle-an-array-in-javascript

var shuffle = function (o) {
    for (var j,x,i=o.length; i; j=parseInt(Math.random()*i), x=o[--i], o[i] = o[j], o[j] = x);
    return o;
}

Part 1: Audio cut-up

The BBC World Service produces and releases an hourly "headlines" recording

• Audio feed (high quality)
• HTML5 media events (timeupdate, durationchange, seeked)
• Live demo of HTML5 player events
• HTML5 media events

random play audio code

<audio controls onpause="onpause()" ondurationchange="jump ()" src = "http://wsdownload.bbc.co.uk/worldservice/css/96mp3/latest/bbcnewssummary.mp3"></audio>

<script>
var a = document.getElementsByTagName('audio')[0]
var id 

function jump (){
    //var a = document.getElementsByTagName('audio')[0]
    a.currentTime=Math.random()*a.duration
    a.play()
    id=setTimeout(jump,3000)
}

function onpause (){	
   clearTimeout(id)
}
</script>