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From: saito <saitology9@gmail.com>
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Subject: Re: Image background
Date: Thu, 17 Oct 2024 16:42:15 -0400
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On 10/17/2024 3:56 PM, Rich wrote:
>> Thank you - I missed this page.  Does this command apply to non-png
>> images?
> 
> It applies to all Tk photo images.
> 
> Whether you can save the transparency to a file will depend upon the
> file format you choose to save the result into.
> 

Thank you. I know image processing is a rabbit hole. My question was 
much simpler. I wanted to determine what the background color is (if 
possible, and it is ok if not), and replace it with an alpha color. Paul 
Obermeier's code answers my question perfectly.

Thanks again to both of you!