This is a legal question and I want to know if I can continue the way I work in a commercial environment. This is not about if I can blatantly take images from the web and use them as they are.
What I do is mostly icons and iconographic imagery where in the end no one can tell if I used an image that doesn't belong to me as a starting point.
Here is an example.
See, technically I stole.
I'd like to know if this is perfectly okay and counts as a new work or if it's sort-of okay because I might not get into legal trouble. Or maybe I should be really careful.
I actually don't know.