Methods, apparatuses and systems are disclosed for accelerating the operation of the automatic functions of an imager, e.g. a camera system. The automatic functions may, for example, include one or more of auto-focus, auto-exposure and auto-white balance. A special “windowing mode” is implemented in which information is acquired from only a subset of defined windows from the full pixel array area in order to set image capture parameters of the imager in accordance with current scene conditions.