code

	<canvas id="c" width="300" height="300" style="border:1px solid #000000;"></canvas>
	<button type="button" id="submit">Submit!</button>
	<button type="button" id="clear">Clear!</button>
	<script>
		$(document).ready(function(){
			var canvas = new fabric.Canvas('c');
			canvas.isDrawingMode = true;
			canvas.freeDrawingBrush.width = 5;
			$('#submit').click(function(){
				var image = canvas.toDataURL("image/png").replace("image/jpeg");
				console.log(image);
			});
			$('#clear').click(function(){
				canvas.clear();

			});
		});
	</script>