Hi
I think this is simply not possible :
the only way for a browser to display an image is "getting" it from an http link (either IMG or background-image ...).
So, if you want to "dinamically" display an image, your ajax callback should return either the source link or "data" that can further been processed to get the right image through a source link.
For example, for the second option, you can develop a PHP file that returns your image, depending on data provided within the src :
On browser side, you create your image with your ajax callback using jQuery and setting the src with data provided by the callback :
<img src=my_file.php?ref=image12 />
And on server side your PHP my_file.php will return the right image according to "ref" parameter. Only my_file.php should be "visible" by the browser, and your images can be hidden elsewhere.
Hope my explanation is clear enough.
emile
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