$('#elem').wScratchPad({
    width           : 210,                  // set width - best to match image width
    height          : 100,                  // set height - best to match image height
    image           : 'images/slide1.jpg',  // set image path
    image2          : null,                 // set overlay image path - if set color is not used
    color           : '#336699',            // set scratch color - if image2 is not set uses color
    overlay         : 'none',               // set the type of overlay effect 'none', 'lighter' - only used with color
    size            : 10,                   // set size of scratcher
    realtimePercent : false,                // Update scratch percent only on the mouseup/touchend (for better performances on mobile device)
    scratchDown     : null,                 // scratchDown callback
    scratchUp       : null,                 // scratchUp callback
    scratchMove     : null,                 // scratcMove callback
    cursor          : null                  // Set path to custom cursor
});

<script type="text/javascript" src="./wScratchPad.js"></script>
<link rel="Stylesheet" type="text/css" href="./wScratchPad.css" />

$("#elem").wScratchPad({
    scratchDown: function(e, percent){ console.log(percent); },
    scratchMove: function(e, percent){ console.log(percent); },
    scratchUp: function(e, percent){ console.log(percent); }
});

var sp = $("#wScratchPad").wScratchPad();

sp.wScratchPad('width', '200');
sp.wScratchPad('image', './images/winner.png');
sp.wScratchPad('image2', './images/scratch-to-win.png');
sp.wScratchPad('cursor', './cursors/coin.png');
sp.wScratchPad('reset');

$("#wScratchPad").wScratchPad({
    cursor:'./cursors/mario.png'
});

$('#elem').wScratchPad('reset');
$('#elem').wScratchPad('clear');
$('#elem').wScratchPad('enabled', <boolean>);