Watermarked information embedding apparatus

• US 8,270,663 B2
• Filed: 10/25/2006
• Issued: 09/18/2012
• Est. Priority Date: 11/10/2005
• Status: Expired due to Fees

• Current Assignee: Oki Data Corporation (OKI Electric Industry Company Limited)
• Original Assignee: Oki Data Corporation (OKI Electric Industry Company Limited)
• Inventors: Maeno, Kurato
• Primary Examiner(s): Park, Chan S
• Assistant Examiner(s): YENTRAPATI, AVINASH
• Application Number:
  US11/585,817
• Publication Number:
  US 20070104350A1
• Time in Patent Office: 2,155 Days
• Field of Search: 382/176, 382/464, 382/177, 382/178, 358/1.9, 358/2.1, 358 31- 332
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: G06V 30/40 Document-oriented image-based pattern recognition
• 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 1/32219 involving changing the position of selected pixels, e.g. word shifting, or involving modulating the size of image components, e.g. of characters H04N1/32224 takes 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 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

Abstract

The watermarked information embedding apparatus which inputs an image and embeds watermarked information in the input image, comprises: picture element determining means which determines whether it is a picture element constituting a background image for each of picture elements which constitute the input image; background picture element removing means which removes all of background picture elements determined as picture elements constituting the background image by the picture element determining means; and watermarked information embedding means which embeds the watermarked information in an image constituted by a picture element from which the background picture element constituting the input image is removed by the background picture element removing means.

Claims

1. A watermarked information embedding apparatus which inputs an image having picture elements and embeds watermarked information in the input image, comprising:

picture element determining means which determines whether it is a picture element constituting part of a background image for each of the picture elements which constitute the input image;

background picture element removing means which removes all of background picture elements determined as picture elements constituting the background image by the picture element determining means; and

watermarked information embedding means which embeds the watermarked information in an image constituted by picture elements from which the background picture elements have been removed by the background picture element removing means,

wherein an aggregation of picture elements which constitute the input image forms dots,

wherein the picture element determining means classifies picture elements constituting dots smaller than a predetermined size as picture elements which are to be removed as candidates for the background picture and which belong to a foreground image,

wherein the picture element determining means also classifies dots based on their shapes and designates dots with predetermined shapes as candidates for the background picture,

wherein the picture element determining means also calculates cycles of dots based on their positions and removes picture elements for which cycles have not been successfully calculated as candidates for the background picture, classifying them as at least a part of the foreground image,

wherein the picture element determining means also designates picture element remaining as candidates for the background picture as picture elements of the background picture, and

wherein the background picture element removing means estimates a position of each background dot and determines whether the background dot should be entirely or partially removed, based on the shape, the cycle and the phase of the respective background dot, when the respective background dot is superposed on at least one of a plurality of picture elements constituting a character, a sign or a ruled line of the input image.

2. The watermarked information embedding apparatus according to claim 1, wherein the background picture element removing means removes a portion of a superposed background dot that is not superposed on at least one of the plurality of picture elements constituting a character, a sign, or a ruled line of the input image.

3. A watermarked information embedding apparatus which inputs an image having picture elements and embeds watermarked information in the input image, comprising:

picture element determining means which determines whether it is a picture element constituting part of a background image for each of the picture elements which constitute the input image;

background picture element removing means which removes all of background picture elements determined as picture elements constituting the background image by the picture element determining means; and

watermarked information embedding means which embeds the watermarked information in an image constituted by picture elements from which the background picture elements have been removed by the background picture element removing means,

wherein an aggregation of picture elements which constitute the input image forms dots,

wherein the picture element determining means classifies picture elements constituting dots smaller than a predetermined size as picture elements which are to be removed as candidates for the background picture and which belong to a foreground image,

wherein the picture element determining means also classifies dots based on their shapes and designates dots with predetermined shapes as candidates for the background picture,

wherein the picture element determining means also calculates cycles of dots based on their positions and removes picture elements for which cycles have not been successfully calculated as candidates for the background picture, classifying them as at least a part of the foreground image,

wherein the picture element determining means also designates picture element remaining as candidates for the background picture as picture elements of the background picture, and

wherein the background picture element removing means estimates a portion of each background dot except for any superposed portion thereof, the superposed portion being a portion that is superposed on at least one of a plurality of picture elements constituting a character, a sign, or a ruled line of the input image.

4. A watermarked information embedding apparatus which inputs an image having picture elements and embeds watermarked information in the input image, comprising:

picture element determining means which determines whether it is a picture element constituting part of a background image for each of the picture elements which constitute the input image;

image separating means which separates, from the input image, a background image comprising background picture elements which are determined as picture elements constituting the background image by the picture element determining means; and

watermarked information embedding means in which the background image of the input image is separated by the image separating means and the watermarked information is embedded in the remaining image;

wherein an aggregation of picture elements which constitute the input image forms dots,

wherein the picture element determining means classifies picture elements constituting dots smaller than a predetermined size as picture elements which are to be removed as candidates for the background picture and which belong to a foreground image,

wherein the picture element determining means also classifies dots based on their shape and designates dots with predetermined shapes as candidates for the background picture,

wherein the picture element determining means also calculates cycles of dots based on their positions and removes picture elements for which cycles have not been successfully calculated as candidates for the background picture, classifying them as at least a part of the foreground image,

wherein the picture element determining means also designates picture element remaining as candidates for the background picture as picture elements of the background picture, and

wherein the picture elements of the background image form dots, and wherein, for each dot of the background image that is superposed on at least one of a plurality of pixel elements constituting a character, a sign, or a ruled line of the input image, the image separating means deletes a portion of the background dot except the superposed portion thereof.

5. A watermarked information embedding apparatus which inputs an image having picture elements and embeds watermarked information in the input image, comprising:

picture element determining means which determines whether it is a picture element constituting part of a background image for each of the picture elements which constitute the input image;

image separating means which separates, from the input image, a background image comprising background picture elements which are determined as picture elements constituting the background image by the picture element determining means; and

watermarked information embedding means in which the background image of the input image is separated by the image separating means and the watermarked information is embedded in the remaining image;

wherein an aggregation of picture elements which constitute the input image forms dots,

wherein the picture element determining means classifies picture elements constituting dots smaller than a predetermined size as picture elements which are to be removed as candidates for the background picture and which belong to a foreground image,

wherein the picture element determining means also classifies dots based on their shapes and designates dots with predetermined shapes as candidates for the background picture,

wherein the picture element determining means also calculates cycles of dots based on their positions and removes picture elements for which cycles have not been successfully calculated as candidates for the background picture, classifying them as at least a part of the foreground image,

wherein the picture element determining means also designates picture element remaining as candidates for the background picture as picture elements of the background picture, and

wherein the picture elements of the background image form dots, and wherein the image separating means estimates a portion of each background dot except for any superposed portion thereof, the superposed portion being a portion that is superposed on at least one of a plurality of picture elements constituting a character, a sign, or a ruled line of the input image.

6. A watermarked information embedding apparatus which inputs an image having picture elements and embeds watermarked information in the input image, comprising:

picture element determining means which determines whether it is a picture element constituting part of a background image for each of the picture elements which constitute the input image;

image separating means which separates, from the input image, a background image comprising background picture elements which are determined as picture elements constituting the background image by the picture element determining means; and

watermarked information embedding means in which the background image of the input image is separated by the image separating means and the watermarked information is embedded in the remaining image;

wherein an aggregation of picture elements which constitute the input image forms dots,

wherein the picture element determining means classifies picture elements constituting dots smaller than a predetermined size as picture elements which are to be removed as candidates for the background picture and which belong to a foreground image,

wherein the picture element determining means also classifies dots based on their shapes and designates dots with predetermined shapes as candidates for the background picture,

wherein the picture element determining means also calculates cycles of dots based on their positions and removes picture elements for which cycles have not been successfully calculated as candidates for the background picture, classifying them as at least a part of the foreground image,

wherein the picture element determining means also designates picture element remaining as candidates for the background picture as picture elements of the background picture, and

wherein the picture elements of the background image form dots, and the image separating means deletes, from the input image, a portion of any superposed background dot except for the superposed portion thereof, and records all of the picture elements constituting the superposed background dot, the superposed portion being a portion that is superposed on at least one of a plurality of picture elements constituting a character, a sign, or a ruled line of the input image.

7. A watermarked information embedding apparatus which inputs an image having picture elements and embeds watermarked information in the input image, comprising:

picture element determining means which determines whether it is a picture element constituting part of a background image for each of the picture elements which constitute the input image;

background picture element removing means which removes all of background picture elements determined as picture elements constituting the background image by the picture element determining means; and

watermarked information embedding means which embeds the watermarked information in an image constituted by picture elements from which the background picture elements have been removed by the background picture element removing means,

wherein an aggregation of picture elements which constitute the input image forms dots,

wherein the picture element determining means classifies picture elements constituting dots smaller than a predetermined size as picture elements which are to be removed as candidates for the background picture and which belong to a foreground image,

wherein the picture element determining means also classifies dots based on their shapes and designates dots with predetermined shapes as candidates for the background picture,

wherein the picture element determining means also calculates cycles of dots based on their positions and removes picture elements for which cycles have not been successfully calculated as candidates for the background picture, classifying them as at least a part of the foreground image,

wherein the picture element determining means also designates picture element remaining as candidates for the background picture as picture elements of the background picture, and

wherein the background picture element removing means, to correct a deformation of an outline of a character of the input image, fills all monochrome picture elements in a given grid position of a grid of dots corresponding to the input image with white, and then returns selected picture element regions to monochrome based at least partly on proximity to the character.