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History of MythTV
Sometime back in 2002 (before May 15th, which is his first website news posting), Isaac Richards decided he wanted something more from his television.
- I got tired of the rather low quality cable box that AT&T Broadband provides with their digital cable service. It's slow to change channels, ridden with ads, and the program guide is a joke. So, I figured it'd be fun to try and build a replacement. Yes, 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.
- So, in late April 2002, I started tinkering with stuff. I bought a cheap TV tuner card from Best Buy, and threw it into my desktop box (P3-550). I started playing around with different video encoders, and eventually decided that NuppelVideo provided the best quality video for the amount of CPU it took up. It's based on a modified RTjpeg codec, and it looks rather nice, in my opinion.
- Unfortunately, the poor P3-550 really couldn't encode and decode video at the same time. So, I took the plunge and bought a better machine — an Athlon XP 1800+. I based the machine off of an Abit NV7-133R motherboard, and put it into a nice black case.
- See the news updates/archives for what's happened since.
What is MythTV?
MythTV is a collection of software that runs under the Linux operating system and provides the functions commonly known as a PVR or DVR (personal, or digital, video recorder) — essentially, it's a computerized VCR, similar to a TiVo or a Replay... but 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
As of early 2008, MythTV is in release version 0.21; this is probably a late-beta to gamma quality release despite its low version number (a common characteristic of Open Source Software projects). Features planned for an upcoming release, or are currently available in the SVN release 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. While it's likely that at some point you'll be able to treat it as an appliance, requiring no special care or maintenance, that day hasn't entirely arrived yet. There are companies selling pre-configured MythTV boxes and those units likely are stable enough to toss on the living room shelf and hand the remote to your kids. But if you're building one yourself (or having someone build one for you), then 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), then there are two approaches you can take:
- Build it out of all those pieces you've got lying around.
- Buy all the pieces from scratch.
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.
A MythTV system can be configured in many ways, the only limit is your imagination, and probably also the money you're willing to put into your setup!
There are two main logical elements in a MythTV system:
- The backend: this is the part that contains the TV capture cards, and stores the recorded video. A typical system will contain at least one backend
- The frontend: this is the part that is connected to your TV screen and lets you watch LiveTV and recorded shows. Of course, the frontend will rely on the backend to get its data.
In a basic configuration, both frontend and backend will be installed on the same physical box, there is nothing wrong with this. This is also the simplest way to put a MythTV setup together.
But you can also separate your backend and frontend hardware in order to create a more advanced setup. For example, you can create a high power backend system that will capture TV through several TV capture cards, will flag commercials, run transcode jobs, etc, and is located 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 actually have as many backends and frontends as you like for a given system, 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 comm flaggging
- 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, with current Intel Core2 CPUs and the equivalent AMD, you can get a really decent system that runs at under 40W and keeps silent!
In the course of this manual, I will often have reason to refer to a Basic Configuration... mostly to point out something that can't be done unless you have more than that. :-)
My idea of 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:
- One Tuner 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.
As you have money and motivation, you can expand your system in many ways.
- You can add more video capture card inputs.
- You can add more storage. Many users on the mailinglist have multiple terabytes of storage(via Storage Groups as of 0.21 and/or RAID, which comes in handy with an HDTV capable system.
- You can add more Front End machines to serve additional television sets.
- You can add additional Back End machines to add even more video capture cards or storage and to offload the processes of Commercial Recognition and Transcoding from the machines doing the recording.
- There is growing list of Unofficial Plugins to expand the capability of your MythBox.
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