Embest SBC8140, Руководство пользователя

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3.4.4 Video Capture Driver
Figure 17: Working Principle of Video Capture
 V4L2 Subsystem:
The V4L2 subsystem of a Linux system works as the medium layer which
helps access the camera driver. The upper-layer applications of the camera
can access drivers through the API of the V4L2. The V4L2 subsystem of the
Linux 2.6 core is designed based on the V4L2 standard.
 Video Buffer Library:
The Video Buffer Library is a part of the V4L2. It provides an assistance
function to effectively manage the video buffer via a queuing method.
 Camera Driver:
The Camera driver allows external codecs to capture video images. It is
registered to layer V4L2 as a master device. Any codec driver that is added
to layer V4L2 as a slave device will be associated with the camera
controller driver through a new V4L2 master-slave interface. Currently the