IMAGE PROCESSING APPARATUS AND IMAGE PROCESSING METHOD

摘要

An image processing apparatus for reducing fluctuations due to a heat haze in an image including a stationary region and a moving object obtains histogram of gradation distribution for each of a target image to be corrected and a frame for correction, and corrects the target image by using the frame for correction while changing a mixing ratio between the target image and the frame for correction depending on similarity between histograms. To adaptively control a size of image blocks for the histograms, the apparatus calculates two indices having different robustness to deformation of an object from image blocks of each of the target image and the frame for correction, and determines suitability of the image block size based on a relationship of the indices. The difference between the histograms and the sum of absolute differences (SAD) between the pixel values can be used as the two indices.

主权项

1. An image processing apparatus, comprising:
an input unit to which input images taken in time series are inputted; an image memory in which the input images are accumulated; a fluctuation correcting device; and a parameter control device, wherein the image memory outputs, to the parameter control device, images of a predetermined frame number among the accumulated input images, the parameter control device obtains a comparison-target pixel block size based on the input images and the images outputted from the image memory and outputs the obtained comparison-target pixel block size to the fluctuation correcting device; and the fluctuation correcting device prepares a time-smoothed image by using the input images taken in time series, makes histogram of the comparison-target pixel block size with respect to each pixel of a target image to be corrected in the input images and the time-smoothed image, and corrects the target image by changing a pixel correction amount for each pixel depending on similarity between the histograms.