Note
This interface has been be suspended from the V4L2 API. The implementation for such effects should be done via mem2mem devices.
A V4L2 video effect device can do image effects, filtering, or combine two or more images or image streams. For example video transitions or wipes. Applications send data to be processed and receive the result data either with read() and write() functions, or through the streaming I/O mechanism.
[to do]