Patent ID: 9088715
Filing Date: 2015-07-21
Classification: G06T,H04N

Abstract:
1. An image processing apparatus comprising: a non-transitory memory storing a program; and a hardware processor that executes the program and causes the image processing apparatus to: calculate a plurality of pieces of tilt information to each pixel of an image acquired in order to estimate a tilt of the image; generate an angle histogram, which is of a frequency distribution of each tilt angle, using the plurality of pieces of tilt information calculated; record correspondences between the plurality of pieces of tilt information and positions on the image in which the plurality of pieces of tilt information are acquired; calculate a distribution degree of the tilt information from the plurality of pieces of tilt information and the positions of the plurality of pieces of tilt information; determine the tilt information that can be used in tilt estimation and the tilt information that cannot be used in the tilt estimation in the plurality of pieces of tilt information from the distribution degree of the tilt information; extract a maximum value or a maximum of the usable angle histogram based on a determination result of tilt information; and estimate the tilt angle of the image from the tilt angle indicated by the maximum value or the maximum, which is detected by the peak detector, wherein the distribution degree of the tilt information is a variance or a standard deviation for the position at the identical tilt angle or each tilt angle existing in the predetermined range.