What is a good DivX player? But the point is, an .AVI movie may have one of serveral codecs required. There is a four letter code in the header of the file that tells what kind of codec you need to play it. The MJPG codec is proprietary, and not easy to get hold of. Vic Robert Bushman wrote: > > Have you tried the DivX player? > http://www.divx.com/divx/linux/ > > I think DivX uses .avi as their extension.