APPARATUS AND METHOD FOR ADJUSTING FOCUS USING ADAPTIVE FILTER

摘要

PURPOSE: An apparatus and a method for adjusting a focus using an adaptive filter are provided to reduce the influence of noise using an adaptive band filter or an LPF(Low Pass Filter). CONSTITUTION: An adaptive filtering unit(40) covers a mask with a certain size on an image signal photographed through a lens, and compares luminance level differences between a central pixel located in the center of the mask and adjacent pixels adjacent with the central pixel with the first to three threshold values. The adaptive filtering unit(40) multiplies pixel values of the image signal by the sum of weight values changed according to the compared results, and outputs an adaptively band-filtered image signal. An HPF(High Pass Filter)(42) filters the high band component of the adaptively band-filtered image signal. An absolute value calculating unit(44) calculates an absolute value of the high band-filtered image signal. An accumulating unit(46) accumulates the absolute value, and outputs the accumulated value as a focus value.