The USB video class deviceÂ
A special video class device is represented by the USB video class (UVC) device , which is a USB device class that describes devices capable of streaming videos, such as webcams, digital camcorders, and so on. They are so important and widely used that they deserve a special section in this chapter to present them.
As said earlier, the CPUs used in most embedded systems usually have an internal video interface, but in some circumstances, these interfaces cannot be used. Examples would be when we need not overload the CPU to video related duties or when the CCD sensor is too distance from where the CPU is located and the data communication is difficult because of the parallel bus used. Well, in these cases, we can use a webcam that supports this standard.
The Linux kernel supports this device class in both kernel side (the uvcvideo device driver) and in user space with the uvcdynctrl utility. The driver, if not enabled into the running kernel, can be enabled...
