- From: Glenn Maynard <glenn@zewt.org>
- Date: Mon, 27 Dec 2010 17:20:51 -0500
On Mon, Dec 27, 2010 at 4:32 PM, Charles Pritchard <chuck at jumis.com> wrote: > I'd like to see Blob output added to the HTML Canvas element : > > Blob getBlob(in optional DOMString type, in any... args); This should be asynchronous, eg: void getBlobAsync(in Function oncomplete, in Function onerror, in optional DOMString type, in any... args); where oncomplete is called with the resulting Blob after compression finishes. Compressing a large canvas can take some time, especially at higher compression levels--saving a fairly small, 1000x1000 image to PNG in Photoshop takes almost five seconds on my system. A UA may also queue canvas operations if the canvas isn't visible; it sometimes seems like Chrome is doing this, though I'm not sure. This gives browsers the option of pushing all of the queue flushing and compression into the background. This shouldn't be required; a UA should be permitted to run the compression synchronously. There should also be a way to abort compression, since any asynchronous operation should be cancellable. (An event-based interface like FileReader's is probably more appropriate.) -- Glenn Maynard
Received on Monday, 27 December 2010 14:20:51 UTC