Calvin Harris -- Lawyer Threatens Suit Over Nude Pics and Video

EXCLUSIVE

Calvin Harris has lawyered up over nude pics of him that are being shopped in the porn and media worlds ... and anyone who dares to post them will see Calvin in court ... fully clothed.

Harris -- who is a wildly popular DJ and the new face/body for Armani underwear -- apparently had a penchant for taking nude pics and videos and sending them to several women. He not only bares all, but proudly mugs for the camera.

We passed on the pics but we can say, he's ripped and, well, Big Sean's got nothing on him .