Selecting a Video Capture Device For Your Application
This article will cover what video capture devices need to be used in different situations and applications. More specifically, the focus of this article will be on the capture of high resolution VGA and DVI signals, although composite video and audio will be discussed. Recording, broadcasting, conference and lecture capture, and computerized equipment capture are all areas where video capture plays an important role.
External USB grabbers are small external devices about the size of a mobile phone that transform a DVI or VGA input into a USB output. The data on the USB output is in a computer-readable format. External USB frame grabbers are portable and can easily be switched between different computers, making them ideal for applications that require a lot of moving around different locations like server administration. VGA to USB devices are also best to use in tight space restrictions and custom applications where a computer needs to be interfaced with a VGA or DVI output device. USB video grabbers are extremely easy to implement in custom applications and, since they can clarify themselves as a high resolution camera on Windows, Mac, and Linux machines, are very easy to set up and use.
If your application involves some sort of far away capture where the source of the signal is not in the same place as the computer being captured to, then networked Ethernet frame grabbers are the solution. Networked video capture devices are used in classroom and conference environments where they are connected to the projector, audio and video outputs. Other applications of Ethernet frame grabbers include far away administration, telemedicine and industrial monitoring. Generally, Ethernet frame grabbers are slightly more expensive than their USB counterparts, but offer more features and the ability to function locally in addition as remotely (using the Internet or LAN).
Finally, internal frame grabbers are video capture devices that are attached to the internal PCI Express slot on desktop machines. Unlike the other two types of video capture devices outlined above, internal frame grabbers are not compatible with laptop computers and are not portable. They also are generally higher priced and offer less features than their internal counterparts. As such, using PCI-based frame grabbers is not suggested unless no other option is given.