Hi all,

I am writing a video capturing application using directshow. One of the functionalities is to allow users to adjust brightness, contrast and white balance through the user interface. The video input device I am using is a Logitech webcam which supports DirectShow.

I have done brightness and contrast using DirectShow's IAMVideoAmp Interface. I firstly using IAMVideoAmp::GetRange() function to get the min and max value of each property and allow user to specify their value within this range. It works fine for brightness and contrast. However, the min and max value for white balance I got are 1 and 0 respectively. Since the value have to be integer, this means I cannot adjust white balance in my application.

I was thinking the white balance is not supported by the driver. But I later found that I can adjust the white balance in my application through the Ligitech control panel.

Can anyone who has experience in DirectShow shows me how I can deal with this problem?

Many thanks,

Ray