The nv122rgb/nv122bgr/nv212rgb/nv212bgr converts NV12 image format
to a 3-channel RGB/BGR image. The inputs to the function are separate Y
and UV planes. NV12 holds sub sampled data, Y plane is sampled at unit
rate, and 1 U and 1 V value each for every 2x2 Y values. To generate the
RGB data, each U and V value is duplicated (2x2) times.
API Syntax