What is a video device?
A video-capture device is a device that is able to convert an analog video signal (such as that produced by a video camera, analog TV tuners, or other analog sources) to digital video. Then, the resulting digital data can be stored in a file (as AVI, MJPEG, or other image formats), sent over the network as a video stream (as MJPEG or H264, for instance), or simply displayed on local display.
Tip
However, as we'll see in the upcoming sections, for Linux, video devices are those devices that are capable of generating a video image (as digital TV tuners), regardless of whether they are digital or analog devices.
An embedded device can be equipped with a video device for several reasons. However, the main one is usually for video surveillance purposes or video monitoring. The basic usage can be simply sending the images to a remote user, but more often, in these last days, it's not rare that the embedded system can do some analysis on the video stream in order to detect...
