Patent ID: 7831091

Claim:
A pattern matching system that outputs a likeness value, said likeness value indicating how much a first and second image accords to each other, said pattern matching system comprising: a receiver that receives a first and second image signal corresponding to said first and second image, respectively, as an area signal, said area signal comprising first and second color signal components or luminance and chrominance difference signal components corresponding to the color of a pattern area of which said first and second images are comprised; a comparison block that compares the signal levels of said area signals corresponding to said pattern areas at the relatively same location of said first and second images; a calculation block that calculates said likeness value, said likeness value varying according to the number of said pattern areas where the absolute value of the difference between said compared signal levels of said area signal of said first and second images is less than a predetermined standard value; an output block that outputs said likeness value; a ratio reading block that reads an amplification ratio by which said first and second image signals are amplified; and a controller that changes the type of said signal components of said area signal used for the comparison by said comparison block and used for the calculation of said likeness value by said calculation block.