Video processing expansion card

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A Video processing expansion card is a computer expansion card that allows a computer to receive television signals, record video and playback video content. ^[1]

1 Video capture
2 Video editing
3 External Capture Device
4 Manufacturers
5 See also
6 Reference
7 External links

[edit] Video capture

Video capture cards are currently PCI card or AGP card that allow a computer to capture composite, or modulated video. While most PCI capture devices are dedicated to that purpose, AGP capture devices are usually included with the graphics adapted on the board as an all-in-one package. Unlike video editing cards, these cards tend to not have dedicated hardware for processing video beyond the analog-to-digital conversion.

There are many applications for video capture cards including converting analog source into some type of digital media, (such as a VHS tape to a DVD), archiving, video editing, scheduled recording (such as a PVR), television tuning, or video surveillence. The cards may have different chip configurations to support each of the functions, such as also having audio capture features.

[edit] Video editing

Once a video source is digitally encoded in the computer, it can be edited with a variety of software tools availble for the given computer platform. However some capture cards are designed with this specifically in mind. These cards often have dedicated hardware for the express purpose of handling the rendering of video streams(instead of the CPU). Some of these cards offer even offer real-time video editing, or a specialised monitor connection which only displays the output of a video being edited as it would appear on a TV(sometimes an actual TV is used).

Editing cards also assist in the dubbing of sound on video clips, adding new sounds, synchronization of sound with video clip (e.g. lip movements are perfectly matched with dialogus etc.), and other common post-production tasks like title generation.

[edit] External Capture Device

While external devices operate outside the PC chassis in most cases, their functionality is largely the same, in some cases identical silicon. Instead of using a PCI or AGP interface, an external device would use USB, Firewire, or PCMCIA cards to interface with the computer. These devices are more commonly associated with mobile or laptop computing because of their small sizes or portability.

Some DV camcorders have analog inputs and could also be recognised as video capture devices.