Image processing system, image processing method, and image processing program recording medium

An image processing method for use in an image processing system, which is configured to analyze input images acquired by a variety of sensors to obtain an output image, the image processing method comprising:

• calculating a desired gradient based on the input images;
• calculating an indication function for the input images, the indication function defining a range that can be taken by the output image and pixel values of a reference image;
• renewing pixel values of one of the input images so as to approximate the desired gradient to produce a renewed image;
• and
• updating pixel values of the renewed image so as to fall within the range that can be taken by the output image and to approximate the pixel values of the reference image, to thereby obtain the output image.

A non-transitory computer recording medium having recorded thereon an image processing program for an image processing system, which is configured to cause a computer to analyze input images acquired by a variety of sensors to obtain an output image, the image processing program causing the computer to execute:

• a gradient calculation procedure of calculating a desired gradient based on the input images;
• an indication function calculation procedure of calculating an indication function for the input images, the indication function defining a range that can be taken by the output image and pixel values of a reference image;
• a pixel value renewal procedure of renewing pixel values of one of the input images so as to approximate the desired gradient to produce a renewed image;
• and
• a pixel value constraint procedure of updating pixel values of the renewed image so as to fall within the range that can be taken by the output image and to approximate the pixel values of the reference image, to thereby obtain the output image.