DivX and Xvid are competing MPEG4 compression formats. While DivX is arguably the more popular of the two, many gurus claim that Xvid offers quality improvements when compared to DivX. Curious, I decided to convert a movie using FairUseWizard and see for myself what the difference was. I chose six different scenes and attempted to take a screenshot at exactly the same point for comparision. Below are the results.
As you can see, neither comes out way ahead. I notice the biggest difference on the shot where the light is shining on his chest armor, and even then, I have to pay close attention to the detail to notice anything. Whether I would notice that at 30 frames per second might be another story.
I would say it all boils down to compatiblity. If DivX is actually more widely supported, then that’s the one I’d recommend. If all players that played DivX also played Xvid, I’d go with whatever one produced the smaller files given the extremely minor differences in quality.