controlling capture frame dimensions

Hello,

i am using directshow to capture live video on pocketpc (QTEK 9100).

the dimension of the captured frames is 144*176.

i would prefer to have obtain a standard frame format (176*144 )

the bmiHeader gives me height -176 and width 144

is it possible to control the dimensions of the captured frames from my camera?

I wonder if it is possible to change this setting ...