This question already has an answer here:
I want to take a photo someone else captured of a celebrity, then use illustrator to manually illustrate a vector of that celebrity, adding my own artistic touch.
The main goal is to be artistic, not technically accurate.
Is it legally safe to use that illustration commercially?
Does it help if I distort the image so it doesn't look like the original photo, (while still keeping the celebrity's face identifiable)?
I've seen many businesses do this - some even take photos outright without altering them at all. I just find it hard to believe they all got permission, or that they are all just cheating.