How to modify "Push Source Desktop" filter to capture specific region

[Tamer Ibrahim]

Hi,

I'm writing a program to capture the desktop in video and found that
DirectShow is very good to do this through the filter "Push Source
Desktop". Since I'm new to DirectShow, I need some help to modify this
filter in order to capture specif region of the desktop. I think
creating a function to alter the "m_iImageWidth" and "m_iImageHeight"
variables in CPushPinDesktop may do that.

Please, through your experience in DirectShow, Is that feasible or
not ? and if yes what is the best way to do that.

Note: I'm using the filter through a .net client by importing the COM
"Push Source Desktop". So, The function in the C++ native filter
should be accessible from that .net managed client.

(Thanks in advance)

Tamer Ibrahim