Wikipedia
GB-PVR was a PVR (personal video recorder) application, running on Microsoft Windows, whose main function was scheduling TV recordings and playing back live TV. GB-PVR is no longer under active development and has been superseded by NextPVR.
GB-PVR also acts as a home media center software with a digital video recorder, a radio station online tuner, a music and movie player, a library of images and other features. The program has been succeeded by a new PVR program, called NextPVR or nPVR for short.
Although GB-PVR supports open interfaces, the core engine code is closed. However developing personal plug-ins is an option to extend the application and these can be closed or open source, depending on the developer's interests. These plug-ins can be developed in C#, VB.NET or C++ and exist some examples available in the GB-PVR official Forums and the GB-PVR Documentation wiki websites. Moreover, the software has been developed with an interface which allows to change the skin view or other graphic elements as the wallpaper.
GB-PVR is mostly an MPEG recording and playback system, but may also play other non-MPG content such as AVI ( DivX/ Xvid), WMV, and other formats that are supported by the codecs installed into a computer's.
It requires a supported TV tuner card, a VMR9 capable display adapter (video card), and a supported MPEG2 Decoder. Other requirements are listed on the GB-PVR web site.