Image processing apparatus and image processing method

摘要

An image processing apparatus includes a gradient calculator that calculates a direction and a magnitude of a gradient of each pixel in an input image using neighboring pixel values; a histogram calculator that calculates a Histogram of Oriented Gradients containing plural sampled directions from the directions and the magnitudes of the gradients calculated for the pixels in a region including the pixel being processed; a storing unit that stores plural smoothing filters and associated Histograms of Oriented Gradients; a search unit that calculates errors between Histogram of Oriented Gradients calculated for the pixel being processed and the Histograms of Oriented Gradients stored in the storing unit and searches the Histogram of Oriented Gradients that has the minimum error; and a filter processing unit that acquires one of the smoothing filters stored in association with the Histogram of Oriented Gradients having the minimum error and determines a corrected pixel value of the pixel being processed by filter processing with the acquired smoothing filter.