I am almost sure that this is a painting. Based on a photograph, for sure (see the distorsion due to a wide angle lens).
I has the same exaggerated feeling of reality than hyper-realistic paintings. Now it can be done with oil, or with Photoshop, but I'd say oil. It's true that you can enhance contrasts and sharpness with Photoshop, but while I am not very good neither with oil nor with Photoshop, I'd find it easier and more fun to do it with oil, though.