Cropping YUV overlay during display?

Hi everybody,

i’ve got the following problem: my YUV overlay’s
borders are filled with junk (16-pixels wide), and
i wouldn’t like it to be displayed when calling

Problem: i couldn’t find a way to crop my overlay,
in the API. Passing a rect with .x and .y equal
to -16 won’t help, because the rest of the picture
is then rescaled (including the remaining left/bottom
border junk).
Also: copying the overlay into a smaller one (without
junk borders) isn’t quite a solution here, because
speed is critical (and this simple memcpy makes me
lose ~20% speed).

any idea?

thanks a lot

Skal /