User Manual:Introduction

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Revision as of 02:34, 16 May 2011 by Peteforsyth (talk | contribs) (Basic Configuration: tweak inconsistent wording)

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This page is up-to-date to MythTV version 0.20, the current release is 32.0

History of MythTV

Early in 2002 Isaac Richards wanted more from his television and thought it might be fun to try to build a replacement for his AT&T broadband cable box.

He says:

I could have just bought a TiVo, but I wanted to have more than just a PVR -- I want a webbrowser built in, a mail client, maybe some games. Basically, I want the mythical convergence box that's been talked about for a few years now.

In late April 2002, he started tinkering, installing a cheap Best Buy TV tuner card in his (P3-550) desktop box. He settled on the NuppelVideo video encoder on a quality/CPU load basis. It's based on a modified RTjpeg codec.

Because the P3-550 couldn't encode and decode simultaneously, he bought an Athlon XP 1800+ and an Abit NV7-133R motherboard, and put it into a nice black case. And the rest is history!

See the news updates/archives for what's happened since.

What is MythTV?

MythTV is a collection of software that provides digital video recording functions (PVR or DVR--personal, or digital, video recorder) — a computerized VCR, similar to a TiVo or a Replay. It runs under the Linux operating system. Since it's open source software, if you don't like the way it does something, you can always change it — that's how much of its current functionality came about in the first place.

In addition to the basic PVR functions of recording and playing back scheduled programs and allowing you to schedule recordings automatically in advance, MythTV has a plugin system that permits it to be extended by other programmers. Plugins currently exist for playing external video, viewing photos, listening to music files, using your TV and a web camera as a video-telephone over the Internet, browsing the web, retrieving current local weather, and many other functions.

There are two types of plugin for MythTV, official, and Unofficial Plugins.

Current Version

As of mid 2010, MythTV is in release version 0.24. Features planned for an upcoming release, or are currently available in the unstable/development version are listed at Under Development. New features in the current release can be found at what's new

I Want My MythTV!

MythTV isn't (yet) for everyone; it's still somewhat high-maintenance. While some companies sell pre-configured MythTV boxes that are probably stable enough to toss on the living room shelf and hand the remote to your kids, if you're building one yourself (or having someone build one for you), the process may be more complicated — this is the price you pay for power and flexibility.

If you want to build yourself a MythTV box (there isn't really a great way to use MythTV unambiguously as a noun; that's my compromise), you can build it from your scrap box, or buy new components.

Which of those two choices you'll make depends a lot on how much money (and what parts) you've got lying around and on how much work you want to do. If you choose each part specifically for the task you will likely spend a little more money and have a lot less hassle.

I built a Myth Box for my sister and since she is the ultimate couch potato (the machine's name is, actually, 'potato' :-) and a hardcore taper (want a copy of a TV episode from 1989? She might have the entire series), the machine has to be a production-quality unit.

For us, this indicated "buy all the parts new" and, since she was planning to have more than one tuner card (between 3 and 5, actually), it indicated "use hardware-MPEG tuners" as well. We'll get into those discussions in an appendix because this manual is aimed at the person with an operational Myth Box in front of them. If you haven't built one yet, check that section out — I'll be including links to useful information for making that decision.

MythTV Configurations

A MythTV system can be configured in many ways--limited only by your imagination and your credit rating.

There are two main logical elements in a MythTV system:

  • The backend contains the TV capture cards, and stores the recorded video. A typical system will contain at least one backend
  • The frontend is connected to your TV screen and lets you watch LiveTV and recorded shows. It gets its data from the backend.

The simplest configuration, puts both frontend and backend in the same physical box.

An advanced setup might separate backend and frontend hardware. For example, a high power backend system might employ multiple TV capture cards, detect commercials, run transcode jobs, etc., and hide in a closet, while one or several frontends can run on low power diskless and silent systems in each room where you want to watch TV. Nice, eh? You can deploy as many backends and frontends as you need, so let your imagination run free and tell us about your setups in this Wiki.

Some people take the opposite approach and actually install MythTV backends on very low power backends such as Linksys NSLU2 units, which are appropriate to record IPTV, for example, as long as they are connected to large disks for video storage.

In any case, the key points for each element are:

  • Backend: large disk capacity, big horsepower in case you want to run transcode jobs or commercial detection
  • Frontend: good graphics card, compatible with the screen you want to use, and just fast enough to display the most demanding type of video you're planning to use.

As you can see, a combined backend/frontend system will need a fairly high-end machine if you want to get good performance, but fear not, Intel Core2 CPUs or equivalent AMDs can provide a decent system that runs silent at under 40W!

Basic Configuration

(This manual will often refer to a Basic Configuration--mostly to point out something that can't be done unless you have more than that! :-)

A Basic Configuration for a Myth Box is this:

  • A Linux Distribution
  • A VGA card supported by linux, optionally with TV-out via composite or s-video (or integrated video on the motherboard)
  • 256MB (preferably 512) or more of RAM
  • A CPU that meets your needs:
    • At least a 800MHz CPU (for hardware-MPEG Tuner Cards, including Digital TV cards)
    • At least a 1500MHz CPU (if not using hardware-MPEG Tuner Cards)
    • At least a 2800MHz CPU (for HTDV recording playback)
  • One tuner card (also known as a "video capture card") of some flavor appropriate to the TV services you have available at your location, (ATI cards are not fully supported)
  • At least 60GB of hard disk space, most of which can be used for storing recordings.

This is a basic system, which will let you schedule recordings and watch live TV, though not at the same time.

Expanded Configuration

With money and motivation, you can expand your system: