[anon4]

Not always. I was trying to write an android application to serve as a frontend to a site by launching a background webview, drawing the elements I'm interested to a canvas and sending the pixels back to the application. (Un)fortunately, after you draw an HTML DOM element to a canvas, you're forbidden from reading the canvas pixels back and there's no flags you can set on the webview to let you do it.

[chucky]

Indeed, if the data in a page's canvas has a different origin, you're not allowed to read pixels back (http://www.w3.org/TR/html/scripting-1.html#security-with-can...).

If the DOM element you draw has the same origin as your canvas it seems like (from my reading of the spec) you should be allowed to do what you describe.