test_video_color_convert is missing a visual verification
This test runs through all possible conversion combination, but does not validate the output. My suggestion is that we use the pack function to set some pixel values, and use unpack to read back some pixels and compare. Some helper are needed as pack/unpack can be in 4 different formats, ARGB, ARGB64, AYUV and AYUV64.
This is related to !86 (merged)