Autofocus control method, autofocus control device, and image processing device

摘要

An autofocus control method, an autofocus controller, and an image processor capable of eliminating influence originated from an optical system, realizing a stable autofocus function. In calculating a focus evaluation value of each sample image obtained at plural focus positions, dark and light patterns of brightness originated from the optical system is reduced by applying smoothing processing to the obtained sample image, and the focus evaluation value is calculated based on the smoothed sample image. Further, the focus evaluation value is standardized by average display brightness of the smoothed sample image to obtain an optimal evaluation value.