How do I internalize an image source?

[Graham]

I guess I should know this, but I couldn't find it in the docs:

An image can either have a source which is an external file with an 
explicit path (the filepath), or it can contains its own source (as the 
result of creating the image via 'import'), in which case the 'source' 
field in the Inspector for the object will be empty and no external file 
will be invoked when the image is displayed. This is explained in the TD.

How can I switch internalised sources without creating new image objects, 
as always happens (AFAIK) when one uses the 'import' command, i.e. how can 
I copy a picture (say a GIF) from one image to another without maintaining 
an external file reference in the second image and without creating a 
completely fresh image? I want to do this so as to maintain the custom 
props etc of a specific object while changing what the user sees on the 
screen, without having to install external files along with my app. I think 
it must be possible, but I can't work out how to do it.

TIA

Graham

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Graham Samuel / The Living Fossil Co. / UK & France