Image processing device and method for identifying an input image and copier including same

A copier comprising:

• scanning means for scanning an original image to produce an input image;
• a signal processing unit including a color processing means for producing color component data from the input image and an image processing device, the image processing device including
• forming means for forming a gradated image from the input image,
• determining means for determining whether the gradated image includes a specified pattern,
• extracting means for, when the determining means determines that the gradated image includes the specified pattern, extracting a portion of the input image corresponding to the specified pattern, and
• comparing means for comparing the extracted portion of the input image with a reference pattern to determine a degree of resemblance between the extracted portion of the input image and the reference pattern;
• and
• printing means for printing a copy of the input image from the color component data produced by the color processing circuit.

A method for identifying an input image, the method comprising the steps of:

• forming a gradated image from the input image;
• determining whether the gradated image includes a specified pattern;
• extracting a portion of the input image corresponding to the specified pattern when the gradated image includes the specified pattern;
• and
• comparing the extracted portion of the input image with a reference pattern to determine a degree of resemblance between the extracted portion of the input image and the reference pattern.