Jit.qt.movie efficiency

Hi,
forgive me as this may be an obvious question.

I have been trying to implement the uyvy colour mode but am not sure how to go about it.

I have read about the jit.gl.slab object but cannot seem to find it in my object library, nor does the system recognise it if I were to type it in manually.

I have also read elsewhere that some processing can be done away from the processor (GPU?) but am unsure what this means or how it is utilised.

I am using a dual 2Ghz Mac G5 and as I understand it macs have a uyvy facility that can be accessed, but have no idea how.

Any help would be gratefully appreciated

Many Thanks

Andy