Image processing apparatus and method thereof

• US 6,873,745 B2
• Filed: 11/28/2001
• Issued: 03/29/2005
• Est. Priority Date: 06/29/1993
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Owada, Mitsuru, Kimura, Takeo, Nagashima, Yoshitake
• Primary Examiner(s): Williams, Kimberly
• Assistant Examiner(s): CARTER, TIA A
• Application Number:
  US09/994,799
• Publication Number:
  US 20020051231A1
• Time in Patent Office: 1,217 Days
• Field of Search: 382/438, 382/178, 382/254, 382/284, 382/100, 382/306, 358/1.2, 358/3.24, 358/501, 358/517, 358/537, 358/538, 358/401, 358/450, 358/458, 358/540, 358/1.9, 380/54, 380/55
• US Class Current: 382/284
• CPC Class Codes: H04N 1/32203 Spatial or amplitude domain methods H04N1/32309 takes precedence
• CPC Class Codes: H04N 1/32208 involving changing the magnitude of selected pixels, e.g. overlay of information or super-imposition H04N1/32219, H04N1/32224 take precedence
• CPC Class Codes: H04N 1/32229 with selective or adaptive application of the additional information, e.g. in selected regions of the image H04N1/32213 takes precedence
• CPC Class Codes: H04N 1/32251 in multilevel data, e.g. greyscale or continuous tone data
• CPC Class Codes: H04N 2201/3233 of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/327 which are undetectable to the naked eye, e.g. embedded codes
• CPC Class Codes: H04N 2201/328 Processing of the additional information

Abstract

The subject matter of the invention is to add information to image data of multicolor image and monochromatic image. An image processing apparatus capable of adding information on raw data performs a dispersion conversion on the spectrum of the additional information by multiplying a code sequence of the PN sequence generator 114 by the additional data which is inputted from the input terminal 111 and converted into serial data in P/S converter 112. At this time, the data sequence transmitted from the image signal processor 102 to the printer engine 107 is converted by the scan converter 109 to correspond to the spatial axis for desperation. The converted data sequence is added to the output from the adder 113 by the adder 110, and reconverted to the original scan by the scan inverter 115.

Claims

1. An image processing apparatus comprising:

input means for inputting image data to which first and second additional information is added so as to be difficult to discriminate with human eyes, wherein the first additional information has been repeatedly added in a first period of time and the second additional information has been repeatedly added to the image data in a second period of time different from the first period of time;

first extracting means for extracting the first additional information in accordance with the first period of time from the data inputted by said input means; and

second extracting means for extracting the second additional information in accordance with the second period of time from the image data inputted by said input means,

wherein an area of an image represented by the image data, to which the first additional information is added, is overlapped with an area of the image represented by the image data, to which the second additional information is added.

2. The apparatus according to claim 1, wherein the first and second additional information is added to the image data after whose spatial spectrum has been converted.

3. The apparatus according to claim 2, wherein said first and second extraction means has conversion means for converting a spacial spectrum of the first and second additional information into an original spacial spectrum of the first and second additional information.

4. An image processing method comprising:

an input step of inputting image data to which first and second additional information is repeatedly added so as to be difficult to discriminate with human eyes, wherein the first additional information has been added in a first period of time and the second additional information has been added in a second period of time to the image data;

a first extracting step of extracting the first additional information in accordance with the first period of time from the image data inputted at said input step; and

a second extracting step of extracting the second additional information in accordance with the second period of time from the image data inputted at said input step,

wherein an area of an image represented by the image data, to which the first additional information is added, is overlapped with an area of the image represented by the image data, to which the second additional information is added.

5. A recording medium for storing a program of implementing an image processing method comprising:

an input step module for inputting image data to which first and second additional information is repeatedly added so as to be difficult to discriminate with human eyes, wherein the first additional information has been added in a first period of time and the second additional information has been added in a second period of time to the image data;

a first extracting step module for extracting the first additional information in accordance with the first period of time from input image data; and

a second extracting module for extracting the second additional information in accordance with the second period of time from the input image data,

wherein an area of an image represented by the image data, to which the first additional information is added, is overlapped with an area of the image represented by the image data, to which the second additional information is added.