A common misconception I see appearing from time to time is not understanding the differences between XBMC and MythTV. XBMC shares common ground with MythTV, but there are some significant differences that make each project unique. In this article, I will highlight these differences while also pointing you in the right direction should you find yourself interested in trying one vs. the other.
MythTV
At its core, MythTV is a DVR/PVR. This means you have an existing source of TV content, like over-the-air television or your cable or satellite box. From there, you’re merely looking to further extend the handling of this content. MythTV is awesome for creating a DVR that offers you lots of extra plugins and widgets to make the experience more entertaining. For MythTV to be worth it though, you need a TV source, tuner card, and the willingness to understand that you may run into trouble with some HD/encrypted content. Sometimes, you’re just out of luck because the content you want to record simply can’t be recorded.
XBMC
Taking its vision from its Xbox Media Center roots, XBMC is basically designed to harness video sources. Local or attached hard drives, network drives or streaming sources. At the end of the day, having access to traditional TV sources is a moot point with XBMC. One common use of XBMC is to view ripped copies of DVDs from a hard drive. Another popular use is relying on the countless XBMC plugins that enable Internet video streaming. The legalities of each option depend on where you live and the licensing behind each source of content.
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XBMC as a MythTV front end
While a bit more involved to get set up, using XBMC as a front end to your MythTV installation might be a solid option. By adding your MythTV as one of the XBMC sources, you have a less Myth-friendly UI to all of your recorded MythTV content. If legality is a concern, this approach might very well be the safest along with sanctioned streaming plugins for the XBMC software as well.