Video capture cards are used to get the picture from the cable, aerial, or satellite television source into the PC.

They decode and capture the video signal from the channel you want to view or record. Often video capture cards will include a tuner to capture an specific TV signal, and are therefore known as 'tuner cards'. (Video capture devices without tuners do exist; usually used in conjunction with an external tuner, such as HD-DVR capture devices recording content from cable or satellite STB which tunes the channel). Sometimes people mistake video capture cards with video display cards which provide the output to the (tv)screen.

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Capture Cards are internal or external devices that record Video or TV into your computer's hard drive. Internal cards fit into a PCI slot on your PCs motherboard, external cards often attach via USB 2.0. There are cards that only record digital video via IEEE1394 (Firewire), or others that can record TV or Video with analog inputs (S-video and Composite). Still others record TV with a coaxial cable input.

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image capture SDK