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answers:

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Excanvas.js allows IE to work with the canvas tag, but the getImageData method is not supported.

Is there any way at all to get the value of a specified pixel in IE (img or VML or whatever other ways bitmaps from a server can be displayed in IE)? I'm assuming there's not.

I'm trying to get rid of a server hit to improve responsiveness of an Ajax app, but I might only be able to do it for FF, Chrome, Opera, and Safari if there's no way to coax the info out of IE.

A: 

As mentioned in the link below...

ExCanvas does not support any of the ImageData functions (createImageData, getImageData, putImageData). Given the way it's implemented it's highly unlikely that we'll be able to add support for it in the VML implementation of ExCanvas.

It should be doable in the Silverlight version but we haven't spent much time on that lately. ExCanvas supports most of the functionality as specified in the initial apple canvas spec but few of the additions added by the gecko implementation and later speced by html5 working group.

The reason being fairly simple, ExCanvas uses VML to do the actual drawing and many of the additions (such as getImageData) requires pixel level access which isn't provided by VML. Your best bet for now would be to keep track of all commands used to draw the canvas and use those to generate an image server side.

http://groups.google.com/group/google-excanvas/browse_thread/thread/7d35fa72dbe1487b

Why can't IE just use a real canvas like all the other kids....

JT703