GVI files are very similar to AVI files and they are encoded in DivX4 with an MP3 audio track.
They can be played using the most popular media players on condition that they do not incorporate DRM encryption.
GVI files are becoming obsolete, as Google is slowly giving up on them. The Google Video Player has been discontinued in 2007, so, if you still have some of these files on your computer and you want to convert them to a widely-used format, Gvi2Avi is the solution.
After obtaining normal AVI files, you can convert them to any desired format without any quality losses.
The only difference between these two formats is the extra list with the FOURCC “GOOG” following the header.