HTPC characteristics

Home theater PC case with front panel and common computer hardware inside.

Beyond functioning as a standard PC, all HTPCs have some additional characteristics.

Television connectivity

Standard PC units are usually connected to a CRT or LCD display, while HTPCs are designed to be connected to a television. All HTPCs should feature a TV-out option, using either a HDMI, DVI, DisplayPort, Component video, VGA (for some LCD televisions), S-Video, or Composite video output.

Quiet / minimal noise

A common user complaint with using standard PCs as HTPC units is background noise, especially in quieter film scenes. Most personal computers are designed for maximum performance, while the functions of a HTPC system may not be processor-intensive. Thus, passive cooling systems, low-speed fans, vibration-absorbing elastic mounts for fans and hard drives, and other minimal noise devices are used in place of conventional cooling systems.

Putting the operating system on flash memory and keeping the media on a separate file server elsewhere in the home keeps the noise and heat generated by a hard drive in another location.

Higher storage capacities

Because of the nature of the HTPC, higher than average capacities are required for HTPC units to allow storage of pictures, music, television shows, videos, and other multimedia. Designed almost as a 'permanent storage' device, space can quickly run out on these devices. Because of restrictions on internal space for hard disc drives and a desire for low noise levels, many HTPC units utilise a Network Attached Storage. Some HTPC units also feature a DVD writer to help users copy and move their media.

TV tuner cards

A TV tuner card is a computer component that allows television signals to be received by a computer. Most TV tuners also function as video capture cards, allowing them to record television programs onto a hard disk. Several manufacturers build combined TV tuner plus capture cards for PCs. Many such cards offer hardware MPEG encoding to reduce the computing requirements. Some cards are designed for analog TV signals such as standard definition cable or off the air television while others are designed for high definition digital TV.

Remote control

Integrating a HTPC into a typical living room requires a way of controlling it from a distance. Many TV tuner/capture cards include remote controls for use with the applications included with the card. Software such as GB-PVR, SageTV, MediaPortal and Beyond TV support the use of Windows MCE and other remote controls. It is also possible to utilize common wireless keyboards and other peripherals to achieve the same effect (though the range may not be as long as a typical remote control).

Comparison with dedicated media devices

     

Advantages

    * Cost - As chipsets with HD capable integrated graphics processors enter the market, the cost of the system can be a fraction of a high-end commercial solution
    * Quality - HTPCs can rival high end dedicated devices.[1]
    * Features - such as pause live tv, usually a feature of high end dedicated devices.
    * Digital media recorder
    * Media server - The HTPC can serve media files to other computers / devices on a network.
    * Gaming - Plays any PC game and application within the game or application's system requirements.
    * Other media - HTPCs can store photo albums and play other media files.
    * Other functions - other functions may include weather forecast, online radio streams, TV schedule, webcam, etc.
    * Other software - other software, such as downloading or file serving, can be run, perhaps in the background.
    * All-In-One - The features found in a HTPC would usually require more than one dedicated component.

Disadvantages

    * Cost - HTPCs can be expensive.
    * Maintenance, Setup - The software in use may require configuration, updates.
    * Complexity - HTPCs are more complex than their dedicated counterparts.
    * Noise - HTPCs can have fans, which can be noisy.
    * Power consumption - HTPCs often use more power than consumer audio/video components.[2][3]
    * Features - May lack proprietary features due to licencing and copyright issues.[4]

Apple Mac systems

Since Apple Inc. alone designs and builds its own Macs, what holds true for PCs may not always hold true for a Mac. While Macs are only available from one supplier, they are no more nor no less suitable for a HTPC than any other system with required specifications:

    * CPU: All Macs built today use Intel dual-core or better processors. As such, all those Macs today decode/encode and/or play high-definition videos of at least 720p resolution (not to be confused with recording HD-TV; the reception of TV signals requires a separate TV-tuner). Older Macs used Motorola G4 or IBM G5 processors. In general, G4 chips could record from and play standard-definition (SD) video and play high-definition (HD), but a G5 was needed to record in HD.
    * TV Capture: Apple may be unique in the HTPC realm in that it has (almost) never offered a TV-tuner option in its systems. Some of the same manufacturers, however, that make internal TV-tuner and software PVR cards for PCs make similar external variants for the Mac (See Software). Despite having an HDMI port and RCA jacks like those on an HTPC, the unique AppleTV is neither a Mac computer nor an HTPC. (See AppleTV for details.)
    * Remote Control: This may be where Apple's systems are most like an HTPC's. The Apple Remote, used in conjunction with Apple's Front Row and Cover Flow, makes it easy for Mac users to browse and enjoy multimedia content on their systems. Front Row in particular was expressly designed for across-the-room use (known in industry parlance as "the 10-foot interface"). And, Apple routinely uses Bluetooth, the across-the-room wireless standard, in its cordless keyboards and mice.
    * Audio: While all of Apple's systems have digital sound, only the high-end Mac Pro tower features dedicated S/PDIF digital outputs. Each of the other systems uses special combination analog/optical-digital audio (microphone and headphone) jacks for their audio input and output.
    * Case: Apple custom designs one case to enclose each of its (desktop) systems. In brief, the Mac Pro tower is roomy and tall but heavy, the aluminum-and-black all-in-one iMac, with its 20-inch or 24-inch LCD built-in, is thin, and the Mac mini is small, lightweight, and quiet. Most Mac-based HTPCs use the Mac mini.
    * HD Video: As mentioned above, all Intel-based Macs can encode/decode and playback standard and high-definition video of at least 720p resolution. As for graphics, the Mac Pro, iMac, Macbook (Oct 2008 or newer) and MacBook Pro all feature dedicated graphics, using either ATI's Radeon HD or nVidia's 8xxx-series (or newer). It is worth noting that, of all four systems, only the Mac Pro's graphics card can be upgraded if desired to something newer in the future.

Software
       

Operating System

HTPC options exist for each of the major operating systems: Microsoft Windows, Mac OS X and Linux.

    * For Microsoft Windows, a common approach is to install a version that contains the Windows Media Center (Home Premium or Ultimate for Vista, or the older Windows XP Media Center Edition). Windows Media Center (MCE) includes additional software that covers the PVR functions of the proposed HTPC, including free program guide information and automatic program recording. However, Windows MCE does not provide an MPEG2 codec, although one can be purchased from Intel, or is alternatively included when purchasing Intervideo's WinDVD. Other MCE compatible MPEG2 decoders are Nvidia's PureVideo and Sonic's CinePlayer DVD Decoder packages. Windows Vista Home Premium and Windows Vista Ultimate already include an MPEG2 decoder.

Alternatively, a HTPC may be built with the addition of a third party software PVR such as GB-PVR, SageTV or Snapstream's BeyondTV to a Windows PC. SageTV and GB-PVR have integrated placeshifting comparable to the Slingbox, allowing client PCs and the Hauppauge MediaMVP to be connected to the server over the network. Snapstream provides heuristic commercial detection and program recompression. When using a faster CPU, SageTV and Beyond TV can record content from TV capture cards which do not include hardware MPEG2 compression. For a free alternative, GB-PVR and MediaPortal provide full home theatre support and good multi-card DVR capabilities. GB-PVR also has a free client, free mediaMVP client, and free network media playback.

    * For Linux, Mythbuntu is a special derivative of Ubuntu Desktop Edition which uses MythTV, just as XBMC Live is a special derivative of Ubuntu Mobile Edition which uses XBMC Media Center, while LinuxMCE combines MythTV and the Kubuntu distribution. KnoppMyth combines the Knoppix Linux distribution with MythTV, a Linux based software PVR, . SageTV provides commercially supported Linux HTPC software that is compatible with most major Linux distributions.
    * For Mac OS X, some HTPC functionality is built into the operating system itself. Specifically, the programs Front Row and Cover Flow, utilized in conjunction with the Apple Remote, let users easily browse through and enjoy any multimedia content stored on their Macs.

Beyond the operating system itself, add-on hardware-plus-software combinations (for adding more full-featured HTPC abilities to any Mac) include Elgato's EyeTV series PVRs, AMD's "ATI Wonder" external USB 2.0 TV-tuners, and various individual devices from third-party manufacturers Miglia, Hauppage, EskapeLabs, Slingbox, and others.


HTPC solutions
       

Stand-alone media management & digital video recording software

    * EyeTV (Mac OS X)
    * Freevo (Linux, Python, free)
    * Front Row (Mac OS X, Apple TV)
    * GB-PVR (Windows, free)
    * MediaPortal (Windows, free)
    * MythTV (Linux, free)
    * Orb (Web/Ajax)
    * Plex, a fork of the XBMC code for Mac OS X users.
    * SageTV (Windows, Mac, and Linux)
    * ShowShifter (Media Center)
    * SnapStream Beyond TV (Windows)
    * XBMC (Linux, Mac OS X, Windows, Xbox game-console, free)

Operating systems

    * eAR OS (Linux)
    * GeeXboX (Linux)
    * KnoppMyth (Linux)
    * LinuxMCE (Linux)
    * Mythbuntu (Linux)
    * Mythdora (Linux)
    * Windows XP Media Center Edition (Microsoft)
    * Windows Vista Home Premium or Ultimate (Microsoft)
    * XBMC Live (Linux)

Hardware

    * ATI Theater Cards
    * Grippity - Handheld Control Solutions
    * Hauppauge Computer Works WinTV PVR Cards
    * HDHomeRun, made by SiliconDust
    * iMON IR Remotes
    * MCE IR Remotes
    * nVidia TV-Tuner Cards (discontinued)
    * TechnoTrend TV cards
    * Vista View Saber Cards (Analog and Combo)
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