I put together a couple of simple tests that render an image to a canvas. One renders from an IMG, while the other renders from an offscreen CANVAS. You can see the code and results here: http://jsperf.com/canvas-rendering/2
In most browsers rendering from an image is much faster than rendering from a canvas, except in Chrome, where the situation is reversed. Can anyone explain the reason for the differences? After all, we are rendering the same pixel data to the same destination.