Removing Smushed versions of full sized images


I recently upgraded from the free version to the pro version of WP Smush, in order to be able to smush full sized photos, which I use in my posts.

What I didn't realize, was that this would slightly change the appearance of the colors in the photos. I assumed that "lossless compression" was all behind the scenes and wouldn't affect the quality/appearance of the images. This is the whole reason that I use the full size images in the first place (wordpress also changes colors/saturation/etc. when selecting other sizes to insert into a post).

So I deactivated the WP Smush Pro plugin, but now am I stuck with these smushed photos? I tried reinserting the images in a recent post, but they still end up with the Smush extensions and are not the orginals.

Your assistance is appreciated.