Video capture card

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Video capture cards are used to get the picture from the cable, aerial, or satellite television source into the PC (compared to video display cards which provide output). They decode and capture the video signal from the channel you want to record. Most include, as is implied here, some sort of RF tuner to capture and convert over the air or cable TV signals, and they are therefore more properly called 'tuner cards' -- video capture cards without tuners do exist (like the Pinnacle DC30 and DV500 series, for example), but these are not commonly used with MythTV.

Types of cards

Analog framebuffer cards

These cards (also called frame grabbers and software encoders) are usually based on a chipset like the Bt848/878 or Conexant cx2388x, and decode broadcast NTSC, PAL, or Secam television. These cards deliver an unencrypted data stream to MythTV, which then encodes to MPEG-4 or RTJpeg using software encoders. Advantages of this type of card are:

  • Low cost
  • High flexibility -- you can choose your encoding method and employ filters prior to encoding
  • If you have the CPU power, MPEG-4 produces better quality with smaller file sizes than the MPEG-2 used with most hardware encoding cards

The main disadvantage of this type of card is the high CPU requirements. Depending on your encoding settings, you may need close to 1GHz of CPU speed to handle a single encoding stream, and more if you have multiple cards or want to play back while recording. MPEG-4 is particularly demanding; for systems with weaker CPUs, RTJpeg consumes less CPU time at the cost of larger file sizes and more digital video artifacts.

Analog Hardware-Encoding Cards

These cards, currently the Hauppauge PVR cards, the AVerMedia M179 and any other card which supports the V4L2 MPEG Encoder API, have a video processor onboard which compresses the tuned video signal into an RTJpeg, MPEG-2, or MPEG-4 program stream before sending it into the computer. The advantages of these cards are:

  • Greatly reduced load on the entire machine (with certain technical caveats). This is particularly important for machines with weak CPUs or when using multiple tuners in one system.
  • The reduced load means that your video stream is less likely to suffer from encoding "hiccups" if a process causes the system to become momentarily too busy to process the video.
  • Most hardware-encoding cards output an MPEG-2 stream, which can simplify backing up to DVD.

The main drawback of this type of card is that you're limited to the video format and encoding options supported by the manufacturer (usually MPEG-2). You can transcode to MPEG-4 after recording to save space, if desired, but this requires post-record processing and will degrade quality slightly.

Digital Hardware-MPEG cards

Digital broadcasting (for DVB and ATSC at least) is in the form of an MPEG-2 transport stream, so unlike analog capture cards, there is no need for any kind of onboard encoding engine, the required program stream is extracted and handed directly to the computer for viewing or saving. Some cards have a hardware Program ID filter (hardware pid) which means the card can extract the required program stream from the transport stream itself.

In either case, the computer power required to save a MPEG-2 transport stream (but not view it) is very small, being only what is required to shift data from the PCI/USB bus and save it to disk.

Confusingly, many useful tools for working with MPEG-2 transport streams have "dvb" in their names, even though they work just as well with MPEG-2 transport streams derived from "ATSC" broadcasts.

Some digital capture cards also support analog (NTSC or PAL) transmissions, usually via a frame grabber. If your digital capture card lacks such hardware and you want to record both digital and analog transmissions, you'll need to buy a separate analog capture card - either a frame grabber or a hardware-encoding card.

With the world moving towards digital broadcast standards, this type of card is likely to become dominant in the next few years.

Capture Card Matrix

Here is a matrix, listing cards with their related drivers.

Card Driver Works with MythTV? Hardware-based encoding? CC Stream? CC MPEG2? Notes Reporter
Aimslab Video Highway Xtreme bttv Yes No ? ? Non-standard internal audio-out pinout, but labeled on PCB. Requires BTTV Module parameters card=14 tuner=2 HeK
ADS Tech Instant TV_Deluxe - PTV305 kernel>=2.6.20rc2, ,cx88, cx88_blackbird Yes Yes ? ? Cx23880-19/Cx23416-12/TDA8275+TDA8290 Dreality
ATI All-in Wonder ? No NA NA NA Does not work with MythTV Unknown
ATI HDTV Wonder kernel >= 2.6.15, cx88-dvb Yes No  ?  ? broadcast HDTV Unknown
ATI TV-Wonder bttv Yes No Yes ? Discontinued Unknown
ATI TV-Wonder Pro cx88xx Y N ? N This is the Conexant based card Lucidity
ATI TV-Wonder VE bttv Y N Y ? Discontinued Unknown
AVerMedia M150-D cx88-blackbird Yes (with caveats) Yes No (?) No (?) Card is finicky and unreliable; see card's wiki entry for details. Srs5694
AVerMedia M179 IVTV stable Y Y ? ? Unknown
AVerMedia DVB-T 771 bttv I believe Yes Yes ? ? WhyTey
AVerMedia DVB-T 777 saa7134 Yes ? ? ? raintonr
ComPro VideoMate TV PVR/FM v4l2 No No ? ? MythTV 0.19, Works with KdeTV Ola A
Compro VideoMate TV Gold Plus saa7134 Yes ? ? ? Audio capture from PCI bus works, see wiki writeup for more info Lynchmv 13:45, 2 June 2006 (UTC)
DVICO Fusion DTVDVB-T ? Yes ? ? ? DVB-T, more info, also note Patch for 2.6.12 kernel Unknown
DVICO FusionHDTV5 Gold Kernel >= 2.6.17 Partial No ? ? Tested with 2.6.17. Read more at link Jason
DVICO FusionHDTV5 RT Gold Kernel >= 2.6.15 Yes Yes ? ? DVB Driver from linux kernel 2.6.16, Works out of the box since Ubuntu 6.06 more info. The digital and analog tuner are recognized in one single card since Myth 0.20. Myth shows all of the digital and analog inputs including the S-video and RCA inputs on the card. Tested 43 HDTV channels with an indoor digital antenna Jylups
DVICO FusionHDTV II (and DVICO FusionHDTV3) Kernel ??  ??  ??  ?  ? (hardware details: [1], [2], [3] [4]) ([5] mentions that the "II" and "3" are very similar) User:DavidCary
FireWire capture NA Yes NA ?? ?? Caption stream is avail when playing through cable box, but not through mythtv Unknown
Hauppauge DEC2000-T ? Partial ? ? ? DVB-T, USB external tuner Unknown
Hauppauge Nexus S ? Yes ? ? ? DVB-S, STV02998 based Mpeg Encoder Unknown
Hauppauge PVR-500 IVTV >= 0.4.0 Yes Yes Not supported in MythTV Yes in some versions of ivtv Dual TV tuners, single FM Radio tuner, no remote. See Hauppauge_PVR-500 on this wiki! User:Michel
Hauppauge PVR-350 IVTV stable Yes Yes Not supported in MythTV Yes Has TV-out and if the option to encode CC in MPEG datastream is enabled, PVR-350 TV output can also pass it back to the television CC decoder. Not recommended for new purchases, as mpeg decoding does not support advanced myth functions (like fast-forwarding) and future versions of myth will use OpenGL, which will not work on this card. See Hauppauge_PVR-350 on this wiki! Unknown
Hauppauge PVR-250 IVTV stable Yes Yes Not supported in MythTV Yes See Hauppauge_PVR-250 on this wiki! Unknown
Hauppauge PVR-150 IVTV stable Yes Yes Not supported in MythTV Yes in some versions of ivtv All versions have one TV tuner. Different versions exist, some with FM Radio tuner (but no remote), some with remote (but no radio). See Hauppauge_PVR-150 on this wiki! User:Michel
Hauppauge HVR-1600 No Linux support No Yes No No Does not work with MythTV or Linux yet because of the new Conexant CX23418 chip used to encode MPEG-2. The card has two tuners, one supports both ATSC (8-VSB) and Clear QAM up to 1080i resolution, the other does standard NTSC hardware encoding to MPEG-2. You can watch or record on both tuners at once.

Hauppauge has stated that Linux support for the WinTV-HVR-1600 is in process, however the company themselves are not working on a driver. A message to Hauppauge support asking about the supposed "in process" driver resulted in the following response: "we don't produce Linux drivers only Win XP/Vista drivers. You will have to refer to the Linux community for that." Evidently, they are telling their customers that the Linux community "process" of getting pissed off with lack of vendor support and writing drivers without assistance will eventually produce something that works with their hardware.
Randall, Robert Ham
Hauppauge WinTV-Go bttv Yes No Yes No See Hauppauge_WinTV-Go on this wiki! Unknown
Hauppauge WinTV 38061 Rev B226 bttv Yes No ? ? Use btaudio for sound Unknown
Hauppauge Nova-T bttv MythTV version 0.18.1 or older No ? ? DVB-T, Digital Terrestrial Unknown
Hauppauge Nova-T cx88-dvb Yes No Yes Yes (UK) DVB-T, Digital Terrestrial User:Fishter
Hauppauge Nova-T 500 Kernel >= 2.6.19 dvb-usb-dib0700 Yes No Yes Yes (UK) DVB-T, Digital Terrestrial [6]
Hauppauge Nova-S CX88-DVB Kernel >=2.6.15 Yes No ? ? DVB-S, Digital Satellite Unknown
Hauppage WinTV PVR (Roslyn) kernel>=2.6.18 ? Yes ? ? Should be supported with MythTV 0.20 Unknown
Hauppauge WinTV-PVR-USB2 kernel>=2.6.18 or separate package Yes Yes No No Looks like a PVR-x50/500 card to software Srs5694
K-World Xpert DTV - DVBT PCI ? Y DVB-T, has aerial passthru Unknown
Leadtek LR6650/ DTV1000 - DVBT PCI cx88-dvb Kernel >=2.6.12 Yes DVB-T, has aerial passthru Juski
Leadtek DTV2000H - DVBT & Analog PCI cx88-dvb Kernel Yes DVB-T, Analog. Seperate antenna connector for DVB-T and Analog Stev391
Lifeview TV Walker Twin (USB) m920x (linuxTV HG) Partial Dual DVB-T. Single antenna connector, works with gxine. To get card working setup VLC to Network Stream and use an IPTV tuner in MythTV. Stev391
Matrox Rainbow Runner G-Series mgavideo Yes Yes No No Discontinued Unknown
pcHDTV HD-3000 kernel >= 2.6.12, cx8800, cx88-dvb, cx22702, or51132 Yes No No No broadcast HDTV. User:rtsai1111
pcHDTV HD-5500 kernel >= 2.6.16, cx88-dvb Yes No No No DIGITAL SDTV/HDTV in 8ESV, QAM64, QAM128, QAM256, and Analog NTSC Dreality
Pinnacle PCTV HD  ?  ?  ?  ?  ? ATSC, NTSC, Clear QAM, FM. Conexant CX23883-39 Chipset GBob
Plextor ConvertX wis-go7007-linux-0.9.7 Yes Yes No No USB external device (MPEG4) MythTV 0.18
Silicondust HDHomeRun MythTV >= 0.20 Yes Yes No No ATSC Digital TV, Dual tuners, TCP/IP network. Technically there is no hardware encoding however the device streams mpeg-2 directly from the ATSC broadcast --> no encoding requ'd. User:jafa
Technisat AirStar HD-5000 kernel >= 2.6.x, dvb B2C2, LGDT330x Yes No No No OTA and Clear QAM HDTV. User:digitalboy
Technotrend C-1500 budget-ci Some card revs Newer cards with different tuner (antenna in and out) might not work under Linux akif, User:Per Olofsson
Terratec Cinergy 400 ? Yes No ? ? Unknown
Terratec Cinergy 600 ? Yes No ? ? Unknown
Twinhan MiniTer DVT PCI kernel >= 2.6.8 No No ? ? DVB-T Australia. Provides MPEG2 stream from digital signal User:Bill
Geniatech Digistar cx88xx Yes No ? No This is the Conexant based card User:versteckt

Removed from matrix because I could not find any info at vendor websites (please re-add if you have info about these!):

  • Aver Desktop PVR

Detailed Information

Cards that work

ATSC (HDTV) cards

Hardware Encoder cards

Software Encoder cards

DVB cards

  • AVermedia DVB-T (Bt8xx)
  • AVerMedia DVB-T 777 (saa7134) PCI
  • DVICO FusionHDTV DVB-T (More Info)
  • DNTV Live! DVB-T Pro (More Info)
  • Hauppauge WinTV-Nova-T PCI Cards
  • Hauppauge Nova-T (Digital Terrestrial)
  • Hauppauge Nova-S (Digital Satellite)
  • Hauppauge Nova-SE2 (Digital Sattelite)
  • Hauppauge Nexus-S (STV02998 based) Mpeg Encoder
  • Leadtek LR6650 DVB-T and other cards based on the Conexant 'reference' DVB-T design.
  • Nebula Electronics DigiTV PCI Rev 1 (Bt878, Nxt6000) Rev 2 (Bt878, Zarlink MT352) (Digital Terrestrial)
  • Pinnacle PCTV DVB-S (Bt878)
  • Technisat Sky Star 2 TV PCI
  • Technotrend C1500 (DVB-C) - Warning: newer version with different tuner (antenna in and out) might not work under Linux
  • Technotrend T1500 (DVB-T)
  • Twinhan MiniTer DVT PCI
  • Geniatech Digistar

USB Capture Cards

Cards that don't work

  • ATI All-in-Wonder cards

The ATI drivers provide a kernel module for basic V4L support which allows for capturing video from the device as it is playing. They do not, however, provide the tuner functions necessary for MythTV to select channels. Instead, they implement their channel tuning using the Xv extensions of X-Windows. A solution might be to patch the MythTV source code to recognize the ATI hardware and use Xv frequency changing to change the channel rather than solely relying on the V4L tuning functions. Then it would depend on whether the V4L support for capture is adequate enough in the ATI drivers for MythTV to work. It also might be possible to use an externally called Xv channel changing utility to change the channels.

The ATI All-in-Wonder card cannot (it is said elsewhere on the internet) send video across the PCI bus. It can only show video on the VGA output on the card. It is on this basis that neither the card nor drivers are appropriate for use with mythtv.

  • PVR-350 all functions work, but TV-Out isn't well suited for Myth, since it isn't accelerated and the MPEG decoder isn't well supported any longer.
  • Hauppauge WinTV-HVR 1600. Includes both an ATSC high-def tuner and an analog cable TV tuner, but is apparently not yet supported by the IVTV drivers.

External Links