Converting .m4v videos to .ogv format.
Converting iTunes Video Files directly to Ogg Video Files (.m4v to .ogv conversion) is doable, and should be quite straightforward.
Use one of several currently available video editing programs or conversion tools, such as Freemake Video Converter or Corel VideoStudio Pro, to convert .m4v to .ogv.
A video editing software package
One of the most popular and successful free video conversion softwares