Full-featured Card

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Revision as of 15:01, 26 November 2007 by Carlb (talk | contribs) (DSP)
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A Full-featured Card (short full-featured or sometimes premium) is a term which originally described the early Siemens, Hauppauge and TechnoTrend DVB-Cards with onboard AV711x chip used as MPEG2 Decoder. The TechnoTrend Skystar 1.x / Hauppauge WinTV Nexus cards required that the host PC download firmware to the card on startup, as they contained their own embedded DSPs.

Cards without a built-in MPEG decoder are called budget in this terminology.

Bear in mind that this naming can be deceptive; for modern systems with powerful CPUs a "full-featured" card may be simply a waste of money as a recent PC with more than ~500MHz should be able to decode MPEG2 streams in software without any extra cost.

For a long time the VDR Project unfortunately forced its users to install at least one of these expensive cards in their system.

No modern card design repeated this approach, Microsoft even denies to support this type of cards in their BDA Driver Architecture.

Today it is however highly recommended to install the VDR Software Decoder Plugin instead and let the "Full-featured Cards" die better sooner than later. You can spend your money a better way, invite your girlfriend for a ice-cream or drink some beer with your friends.

Full-featured vs Budget?

A full-featured card can do everything that the budget PCI card can do, but also provides hardware DSP and MPEG2 decoding (uncompressing the received video data). This typically comes at a 100% increase in cost, compared to cards which rely on these functions to be available in software.

The full-featured card may be a sensible option if:

  • A slow host computer (or one running multiple tasks) is being used to view live TV. Even a 200MHz Pentium MMX can display a usable image from a full-featured card, despite being too slow to decode most MPEG video streams in real-time.
  • An analogue output directly from the card to a sound system or composite monitor is desired. Once tuned to an unencrypted free-to-air signal, the premium card will output an analogue A/V signal with no further processor intervention. It will keep playing until reset, even if the host computer is unresponsive or crashed.

The full-featured card offers no real advantage under any of these conditions:

  • The card is being used solely to record (not view) MPEG2 programming. Stored video, including DVD's, must retain a compressed format in order to be manageable in size.
  • The card is being used solely to stream received MPEG2 to a remote network computer or to an MPEG-capable device (such as the MediaMVP, which has its own MPEG hardware)
  • The received video is being sent to a display adapter which already supports MPEG natively
  • The original programme source is HDTV (for cards where the provided hardware decoder is SDTV-only)
  • The transmitter is sending non-DVB or proprietary-format content, non-MPEG data (such as a satellite Internet downlink), or an incompatible video format. These include MPEG 4:2:2 or MPEG4/DivX (if the card supports standard MPEG2 only).
  • The card is used in a fast computer with adequate resources to decode MPEG in software.

The full-featured cards are PCI-only, as they rely on being able to transfer massive amounts of uncompressed video to a display card over the system bus. USB DVB tuners will normally leave MPEG2 DVB data in its original MPEG-compressed form (easier to transfer) and are therefore not implemented as premium/full-featured cards.