most likely counts as AI-assisted art, which is copyrightable with you as the owner

like most things copyright there is a gray area there

but in most cases it's either pretty clear and courts would most likely rule in your (copyright holder) if you somehow manage to hit the perfect middle of the gray area

through if you tell the court "the author is my AI" (like in this case), the outcome is pretty obvious

also for better understanding using AI doesn't erase copyright, it just doesn't add it. So if you image was copyrightable before you used an AI tool to change it will stay copyrightable (as long as the original image is still in there to a reasonable degree).