Screencapping with DivX

Searched the memories, no help. I have a movie in the format of DivX and I can't get screencaps of it. I tried opening it in several programs (VLC Player, DVDX, Windows Movie Maker), but they don't accept DivX files. I've also tried the PRT SCR button while in DivX player, but when I paste it, it shows a black image. Any help appreciated! Please and thank you. :)