Difference between revisions of "User Manual:Setting Up"

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m (Audio out: Typo)
(XvMC (XVideo Motion Compensation))
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====Xv (XVideo)====
====Xv (XVideo)====
Xv is an extension to X (the X window system) that provides offloading of scaling and colorspace conversion. Support for this is the recommended minimum for use with MythTV. This method requires that any UI elements must be composited into the video in software, so is not recommended when OpenGL is available.
Xv is an extension to X (the X window system) that provides offloading of scaling and colorspace conversion. Support for this is the recommended minimum for use with MythTV. This method requires that any UI elements must be composited into the video in software, so is not recommended when OpenGL is available.
====XvMC (XVideo Motion Compensation)====
[[XvMC]] is an extension to Xv that allows for hardware accelerated decoding of video. Currently, MythTV supports using this for MPEG2 only. XvMC provides partial offload, reducing CPU requirements by 30-40% during playback. Modern commodity CPUs have plenty of power for MPEG2 decoding, and have no need to use XvMC. This method is depreciated, and is slated for removal in a future version of MythTV.
====VDPAU (Video Decode and Presentation API for UNIX)====
====VDPAU (Video Decode and Presentation API for UNIX)====

Revision as of 20:17, 11 November 2013

This page is up-to-date to MythTV version 0.20, the current release is 31.0


Here "setting up" means connecting your box to the outside world.

Some things are explained in-depth for the benefit of less-technical users.


  • AC power
  • Video out
  • Audio out
  • Video source(s)
  • Networking

Let's talk about each of these connections and what you do with it.

For information on High Definition systems go to Configuring HDTV.

AC power

It doesn't hurt to check whether your AC "IEC connector" is set to 120 or 240 VAC already.

Since your MythBox needs to be running most of the time to record scheduled programs at inconvenient hours, it's well to use a UPS — an Uninterruptible Power Supply, or 'battery backup'. Surge suppression is a good idea, not only for the power, but for the TV cable, too, if you're using cable TV to feed your box.

If you're concerned about leaving a computer running 24-hours a day, you may also want to experiment with the Mythwelcome plugin; which allows your MythBox to turn itself off and on as needed. Another robust solution is to utilize MythTV's built-in capabilities to powerdown and automatically wake up in time for the next schedule recording -- documented here: ACPI_Wakeup.

At the least, a good surge protector is cheap insurance.

Graphics cards

To connect our MythBox to a display we need a graphics card.



For the past several years, nVidia network cards have been the recommended video hardware for use under Linux. While their closed source binary drivers must be used for proper accelerated support, they are generally easy to install and reliable. Preferred hardware is anything 8000-series or newer.


ATI has historically had a poor track record with respect to Linux, however they have significantly improved over the past several generations, and are fine for MythTV's uses. Preferred hardware is anything 3000-series or newer.


Intel provides onboard video chipsets with their motherboards, and more recently on their processors. Open source drivers are available, and performance is adequate for MythTV.


Via provides onboard video chips for their low power Mini-ITX systems. These systems are not recommended for use with MythTV, and will be incapable of playback of HD content.

Output Methods


This output method will be the preferred output method in future versions of MythTV. With this method, multiple video and UI elements can be converted, scaled, and composited simultaneously on screen using the 3D hardware in your video card.

Xv (XVideo)

Xv is an extension to X (the X window system) that provides offloading of scaling and colorspace conversion. Support for this is the recommended minimum for use with MythTV. This method requires that any UI elements must be composited into the video in software, so is not recommended when OpenGL is available.

VDPAU (Video Decode and Presentation API for UNIX)

VDPAU is nVidia's proprietary decode extension, providing full offload of MPEG-1, MPEG-2, H.264, and VC-1. Some models additionally support MPEG-4 ASP (divx, xvid). This is slated for removal in a future version of MythTV, instead using VDPAU for decoding, but OpenGL for actual output.

VAAPI (Video Acceleration API)

VAAPI is the decode extension used for Intel and AMD hardware, providing similar capabilities as VDPAU. This extension is currently not supported by MythTV.

Connecting your display

You can connect your MythBox to your display, whatever it may be (e.g. monitor, TV, etc by several means:

Composite TV out


This provides an NTSC (or PAL) standard video output signal, which can be sent to a normal TV set using a normal RCA cable.

If your box has NTSC/PAL video out, you'll find an RCA video connector (usually yellow), or a 4-pin Mini-DIN S-Video connector on the back somewhere, which you can connect your monitor to, with the appropriate cable.

VGA output


This can be sent either to a CRT monitor, an LCD or plasma flat-panel, or a projector. Most large monitors and projectors will accept the higher scan-rate signal of a composite output.

For VGA, use an HD-15 cable up to the VGA connector which you will find on the back panel.

Component video


This will require a VGA-to-component adapter and a video card that supports component out. Component video is the best-quality analog signal.

You can also use the Component-Out feature on some nVidia Cards. (I use the 6600GT and it works great) Read my how-to Here

DVI digital connection


For the best quality, especially to modern digital displays such as big-screen LCD, plasma or micro projection solutions, this is preferred. Note that DVI has both digital and analog or combined versions on the same connector. The analog version is compatible with VGA (using an adapter). The digital section is compatible with the latest HDMI connector found on some Hi-Def displays.

Be aware that some of the latest digital displays have hardware content protection built in.



This is the modern DVI, technically backwards compatible. It uses a smaller more manageable connector. You can get an HDMI to DVI adaptor if you need to connect your PC graphics card DVI connector to the latest HDMI displays. The latest HDMI connections will also be able to carry digital multi-channel audio down the same cable.



Some televisions and many video cards provide S-Video connectors, although it is likely less popular than component or composite connections. Many video card manufacturers are known to use plugs of similar design to output various signal types in (for example) 7-pin and 9-pin variants as described below. If the plug has only 4 pins, it is safe to assume it is a standard S-Video connection and signal.

7-Pin Squid Connector


These connectors are typically used to provide multiple signal types from a single source. A video card with this output will generally come with a squid adapter to fit it with, for example, s-video, component, or composite video output plugs, or any combination of them.

9-Pin Squid Connector


This connector, like the 7-pin, requires a squid adapter to access the resulting video and possibly audio.

Other Connectors

It is important to note that the above connector types are by no means the only connections that you might find on the rear of your video adapter. I have, for example, a miniature B-type USB connector on my MythTV frontend video card which is intended for the included squid adapter which outputs Composite, R-audio, L-audio, and S-Video. This is an obscure combination (particularly having audio output on a video output plug) which in my case makes sense, since the plug on the rear of the PC is simply a header connection to the motherboard which has integrated video and audio.

Suffice it to say that provided you connect the appropriate adapter to your output no (or few) provisions should be necessary during your MythTV setup.

Audio out

You may find it helpful to read the section on Sound card.

You can connect your MythBox audio out to your amplifier, TV, or powered speakers.


This is almost always the standard 3.5mm stereo audio jack that most sound cards have, and indeed, the sound card (or onboard audio) of your box is where the audio comes out.

Advanced configurations may support multi-channel (surround) sound making use of the surround sound decoder on your sound card. Typically this will be 5.1 or 7.1 channels of surround sound, the first number denoting the number of speakers/channels and ".1" denoting the sub-woofer channel.


This is the best option for absolute sound quality. This will be via an SPDIF optical or coaxial connector from your sound card, or HDMI from your video card, direct to your home theatre surround sound amplifier or receiver. Decoding of the surround sound is external to your MythBox.

Most modern sound cards have either an Optical or Coaxial Digital out connector. If your sound card allows it, you can set the system to output bit perfect audio to your surround amplifier. This means that ripped CDs output using PCM at 44.1Khz, TV audio is output PCM at 48Khz, and Dolby Digital and DTS surround audio is output correctly to your home theater system.

See the pages on setting up Digital Sound

Configuring Digital Sound

Configuring Digital Sound with AC3 and SPDIF

Video sources

RF tuner

This is done via the threaded "F-connector" or coaxial connector on your tuner card(s), into which you connect the cable from your cable TV feed or outside antenna. If you have more than one tuner card, you'll need a splitter and some jumpers to hook everything up. (Note: in Europe (and maybe other places), you may not have an "F-connector," and it may or may not be threaded.)

If you're recording HDTV or satellite TV signals, there may be special considerations about cabling and tuner cards.

Network tuner

Some companies sell dedicated tuning devices with an RF input. These devices take tuning commands over the network, and convert the digital stream from their antenna input into network packets. One such device known to work with MythTV is the HDHomeRun.

Other capture card inputs

Most tuner or capture cards will allow you to capture not only RF signals from your antenna or cable TV provider, but also locally generated video signals, be they from a VCR, a DVD player (though there are better ways to accomplish this), or a cable box or satellite receiver, for channels you can't get a tuner card to tune directly. More later on this, too.

The input jacks for this, both video and audio, will usually (always?) be on the tuner card itself, in the card cage, as opposed to the video, VGA, and audio-out connectors, which are usually on the motherboard these days (in a section called the "ATX backplane").

You can find a list of capture cards that work with MythTV in the video capture card section.


As this is a significant topic you might find it helpful to read the section on file storage.

In the event that you want to add fault tolerance and redundancy to your storage then you should read the section on RAID.


If you have a standalone MythBox, then you might not ever connect to a network, though this is highly unlikely.

Myth supports multiple front-end machines (for controlling TVs in different rooms) and multiple back-end machines (for splitting up storage, transcode/commercial marking and tuner support), and you connect all of these through a network, preferably using 100-Base-T or Gigabit Ethernet.

In addition, extension modules like MythWeb, MythWeather, and MythBrowser require Internet access. (Actually, MythWeb doesn't need the Internet, just a network connection.)

The biggest reason you will connect to the network is because (most of the time) MythTV gets its program guide data over the Internet. Program guide data is the information in the program guide grids, that allows MythTV most of its PVR functions, like scheduled recordings, etc.

If you are making your MythBox accessible from the outside world, you should almost certainly put it behind a router, and possibly investigate the firewall features of your Linux operating system.

If that's too complicated for you to understand at the moment, then ask a geek for help, or don't open outside-world connections to your box yet.


Most of the time, you'll network your MythBox via Ethernet. The standard jack and plug for this is known as RJ-45, and it looks slightly wider than a telephone jack and has 8 pins (telephone/RJ-15 has 2 or 4 pins). If you have broadband, you most likely use an Ethernet cable to connect to the Internet.


If don't have Ethernet strung around your house, you could use Wi-Fi, or 802.11b/g. 802.11b provides speeds up to 11 Mbits/s and 802.11g provides up to 54 Mbits/sec. Wi-Fi is slightly more difficult to set up than regular Ethernet, just because Linux drivers are usually less mature, so you must check and ensure that the 802.11b/g card that you buy supports Linux before buying it. Oh, and you'll need a wireless router too. Those are cheap these days. Once you have that up, you don't need Ethernet run to the box(es) anymore, which is great!

If you're planning multiple frontend/backend boxes, 802.11b will probably be too slow for acceptable playback. The faster 802.11g should work much better, but may not be enough for HD playback without stuttering.

Remote controls

There are three options for getting remote controls working under Linux

Linux Infrared Control (LIRC)

LIRC provides the software interface between an Infrared Receiver and MythTV. Most modern distributions will have this as standard. It provides great flexibility in mapping infrared remote control keys to MythTV functions. The downside of using LIRC is that you need to get an Infrared Receiver. The easiest way to do this is to buy the Microsoft MCE remote and receiver bundle which is quite low cost. Several popular tuner cards, for example the Hauppauge PVR-150, also come with a built-in IR receiver.

See the Remote Controls category for information on different remote models.

Infrared Keyboard emulation

This is probably the easiest way of getting a remote control to work with MythTV. You simply teach a learning remote such as any of the popular One 4 All or Logitech remotes the keys from your keyboard and hey presto your remote now does exactly what your keyboard does. It's interesting to note that the official Microsoft Media Centre Keyboard is an infrared keyboard but is not yet supported under Linux.

WI-FI Remote plugin

There is now a plugin that provides a web remote front end that can be displayed on a PDA to remote control your Myth Frontend.

http://studwww.ugent.be/~aveys/mythwifi/ <-- Dead link from Ghent University

Here is one example of a site that is still working on a solution. http://oscillatingkinematics.org/wifirc.html For ipod touch / iphone users, there is also mymote, a free application from the itunes store.

Cable/Satellite Box Control


For infrared (ir) output to your cable or satellite box use an IR Blaster.


Some cable and satellite boxes have serial ports that can be used to control them. See Motorola DCT-25xx and Controlling DirecTV Set Top Box (STB) via USB or Serial


If you cable or satellite box has firewire then you can use firewire to change channels and even capture video (if it is enabled). See FireWire.

RF Remotes

Logitech also provides a RF remote called the "UltraX Media Remote". This is a remote that behaves somewhat similar to a keyboard. To get also the special keys working see Logitech UltraX Media Remote

Wireless keyboards

Once your Myth box has been setup you won't need to use your keyboard that much. Many users will often just SSH into their machine or use a remote desktop such as VNC to get access. Of course it's also nice to have a keyboard directly connected, in which case a wireless keyboard is preferred. Have a look at the section on Wireless Keyboards to see which ones work.

Making Sure Your Hardware is Supported by MythTV

Firstly, make sure your hardware is supported by Myth. You can find more information in this wiki at:

If you are having trouble, try:

When you've found a solution that worked it would be nice if you added it somewhere on this site to contribute back to the community. Even just linking to the mailing list archives with a little description would help; search engines will index it and will bring up the correct results earlier in their listings.