Image forming device with forgery prevention

• US 5,568,268 A
• Filed: 04/19/1995
• Issued: 10/22/1996
• Est. Priority Date: 06/15/1994
• Status: Expired due to Term

• Current Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Original Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Inventors: Nakamura, Hideyasu, Kouno, Katsuyuki, Nishigai, Hidefumi, Tsuji, Masato, Kodera, Nobuyuki
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US08/424,669
• Time in Patent Office: 552 Days
• Field of Search: 358/296, 358/400, 358/401, 358/404, 358/406, 358/434, 358/448, 358/444, 355/202, 355/204, 355/209, 355/201, 400/76, 400/692
• US Class Current: 358/296
• CPC Class Codes: H04N 1/00867 with additional data, e.g. by adding a warning message details of embedding additional information in an image H04N1/32144
• CPC Class Codes: H04N 1/0087 with hidden additional data, e.g. data invisible to the human eye
• CPC Class Codes: H04N 1/00875 Inhibiting reproduction, e.g. by disabling reading or reproduction apparatus
• CPC Class Codes: H04N 1/0088 Detecting or preventing tampering attacks on the reproduction system
• CPC Class Codes: H04N 2201/3205 of identification information, e.g. name or ID code H04N2201/3209 takes precedence
• CPC Class Codes: H04N 2201/327 which are undetectable to the naked eye, e.g. embedded codes
• CPC Class Codes: H04N 2201/3271 Printing or stamping

Abstract

An image forming device, such as a color copying machine or a color printer, which processes an input image signal, thereby obtains an output image signal, and forms an output image on the basis of the output image signal. In the image forming device, an information input unit writes some information identifying the copying machine to an area in an information storing unit at the time when a power source is turned on for the copying machine for the first time after the assembly thereof. When the power source is turned on for a second and any subsequent times for the copying machine, the copying machine copies an original sheet in such a state of the machine that the information stored in the area of the information storing unit is added to the output image in the form of a pursuit image which it is hard or impossible to recognize with the human eyes.

Claims

1. As image forming device which processes an input signal to thereby obtain an output image signal, and forms an output image from the output image signal, said forming device comprising:

information generating means for generating information for identifying said image forming device;

information storing means for storing the information;

means for determining whether the stored information is the same as predetermined information;

memory control means, responsive to the determining means, for controlling the storage of information by said information storing means by preventing said information storing means from storing new information after said information storing means has once stored the information generated by said information generating means; and

pursuit image signal adding means for adding to the output image signal the information stored in said information storing means as a pursuit image signal that is not viewable by eye when the output message signal is developed as an image, when the stored information is the same as the predetermined information.

2. The image forming device as defined in claim 1, wherein said image storing means effects the storage of the information generated by said information generating means when a power source supplies a power for the first time to said image forming device.

3. An image forming device which processes an input image signal to thereby obtain an output image signal, and forms an output image from the output image signal, said image forming device comprising:

information generating means for generating information for identifying said image forming device;

information storing means for storing the information;

memory control means for controlling the storage of information by said information storing means by preventing said information storing means from storing new information after said information storing means has once stored the information generated by said information generating means;

information comparing means for comparing the information generated by said information generating means with the information stored in said information storing means; and

pursuit image signal adding means for adding to the output image signal the information stored in said information storing means as a pursuit image signal that is not viewable by the human eye when the output image signal is developed as an image when said information comparing means finds that the information generated by said information generating means is in agreement with the information stored in said information storing means.

4. The image forming device as defined in claim 3, wherein said image storing means effects the storage of the information generated by said information generating means when a power source supplies a power for the first time to said image forming device.