Image processing apparatus, image processing method, computer readable medium storing program and data signal embedded with the program

A non-transitory computer readable medium storing a program causing a computer to execute image processing, the image processing comprising:

• extracting a plurality of feature regions from each of first and second images;
• calculating feature amounts of the extracted feature regions;
• calculating positions of the extracted feature regions;
• selecting pairs of feature regions, which are estimated to be common in the first and second images, based on the calculated feature amounts and the calculated positions of the feature regions;
• narrowing down the selected pairs of feature regions based on similarity in relative positional relation between the feature regions of the first and second images;
• and
• calculating a correction factor used to correct position shift between the first and second images based on the narrowed pairs of feature regions.

An image processing method comprising:

• extracting a plurality of feature regions from each of first and second images;
• calculating feature amounts of the extracted feature regions;
• calculating positions of the extracted feature regions;
• selecting pairs of feature regions, which are estimated to be common in the first and second images, based on the calculated feature amounts and the calculated positions of the feature regions;
• narrowing down the selected pairs of feature regions based on similarity in relative positional relation between the feature regions of the first and second images;
• calculating a correction factor used to correct position shift between the first and second images based on the narrowed pairs of feature regions, wherein
• one of the steps is performed with a processor.