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

摘要

An image processing device is disclosed which can reliably detect documents which may not be copied, which has a very small probability of false positives, and which can handle newly issued documents which may not be copied. In addition, an image processing scheme is disclosed which would accurately obtain the location of a pattern indicating a document to be detected; which would extract that pattern; which would determine correctly whether it is the right pattern; and which would make it difficult for anyone to tamper with the pattern. To achieve this, a specified pattern is imprinted before use on a document which may not be copied, and a previously specified number of positioning marks and dummy marks which identify the location of the pattern may also be imprinted. The device is able to detect a wide variety of documents and perform the required processing at high speed.