How to query controls like brightness or contrast from camera in direct show? It seems that I just can't find anything about it. Any example or guidelines would be appreciated.
The following link describes how an application can programmatically change the image and camera settings on a video capture device: Configure the Video Quality. You should query the webcamera's IBaseFilter interface for interfaces like IAMVideoProcAmp and IAMCameraControl in order to access and modify properties like: Backlight compensation, Brightness, Contrast, Gain, Gamma, Hue, Saturation, Sharpness, White balance, Exposure, Focus, Iris, Pan, Roll, Tilt and Zoom. You can check the amcap SDK sample for details too.