A Personal Video Recorder (PVR) / Digital Video Recorder (DVR) is a device which allows you to record television signals much like a VCR of times past. The main difference is that the PVR records the video to a hard drive and is essentially a computer. This opens up a whole realm of possibilities for storing, manipulating and viewing this information.

Which PVR to use?

There are many choices in the world of PVRs. Even the cable and satelite companies have gotten in on the game (more as a "Hmm I guess this isn't going to go away so we better figure out how to make some money off it" type approach). There are commercial offering such as TIVO, Beyond TV and the software bundled with various computer TV capture devices. Finally there are the free options with Myth TV being the most visible. In our case we weren't interested in paying ongoing licensing fees. We already had a system running Windows for our other media purposes so we decided to opt for a free Windows based application: GB PVR.

Basic recording and playback

The most basic function of any PVR system is the ability to record and playback TV shows. Pretty much any PVR does this well. Most systems are designed such that you sit infront of your TV and use an on screen interface to select what to record / watch from your recorded collection. Since our TV is not high-def and we don't really like reading either small fonts at a distance or page after page of large fonts we didn't find this approach very user friendly. GB PVR fortunately has the option of setting up recordings using a web interface. This allows us to schedule new recordings and view pending ones from any computer in the house (or even outside of the house). For playback we again don't typically use the built-in user interface but rather opt to interact with the files directly. Essentially we just use the software to interface with the hardware cards and handle the actual recording of shows.

Commercial detection and removal

This is the really fun part of using a PVR. After a show has been recorded (or actually even during the recording) the system can scan the recording and detect commercials. There are a number of different options for this (some are built-in to the PVR application, some are add-ons). We use a free add-on called comskip. This program uses a wide range of techniques to detect commercials. For example in many cases the screen will go completely black for a fraction of a second right before and right after a commercial. There is also often a station logo visible during the show but not during the commercials. Sound levels can change during commercials, etc... By looking at all of these different characteristics it is actually possible to identify what is and what is not a commercial automatically. In our experience comskip gets about 95%+ of the commercials and (at least recently) never chops out anything it shouldn't. This means that we can watch TV virtually commercial free. The few remaining commercials we just skip forward over with a simple click of a button.

It has actually gotten to the point where when we do watch commercials (live event of some kind typically) we are so shocked by them that we are left shaking our heads wondering what the world is coming too.

Transcoding

Another neat advantage of having the video on your own computer is that you can then transcode the video into other formats. This can be done for long term storage to a more compact format, or perhaps to use the video on some other type of device. For example if you wanted to take the video with you on your cellphone or iPod you could transcode it down to a size / format that would fit better and take up less space on the device. Given that after a while you will most likely have a very large collection of media to choose from you could even take an entire season of a show and dump it onto a portable device for a trip. The biggest issue with transcoding is that it tends to be a bit finiky to get it all setup just right.

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