When you say "merge", do you mean making one image from two where the 'upper' image completely covers the lower image (like you had physically pasted one photo atop another); or are you looking to merge their alpha channels (as demo'd here) ?

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In reply to Re: merging two .gif or jpg (overlapping) by BrowserUk
in thread merging two .gif or jpg (overlapping) by Mattk470

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