I have made a jsfiddle for you.
<canvas id="canvas" width="480" height="320"></canvas>
<button id="download">Download Pdf</button>
'
html2canvas($("#canvas"), {
onrendered: function(canvas) {
var imgData = canvas.toDataURL(
'image/png');
var doc = new jsPDF('p', 'mm');
doc.addImage(imgData, 'PNG', 10, 10);
doc.save('sample-file.pdf');
}
});
jsfiddle: http://jsfiddle.net/rpaul/p4s5k59s/5/
Tested in Chrome38, IE11 and Firefox 33. Seems to have issues with Safari. However, Andrew got it working in Safari 8 on Mac OSx by switching to JPEG from PNG. For details, see his comment below.