Image processing apparatus for determining specific images

• US 20010030759A1
• Filed: 01/30/2001
• Published: 10/18/2001
• Est. Priority Date: 01/31/2000
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ishida, Yoshihiro, Hayashi, Junichi, Murakami, Tomochika, Iwamura, Keiichi
• Granted Patent: US 7,142,689 B2
• Time in Patent Office: Days
• US Class Current: 358/1.9
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 2201/0064 for copy protection or copy management, e.g. CGMS, copy only once, one-time copy
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• CPC Class Codes: G06V 10/40 Extraction of image or video features
• CPC Class Codes: H04N 1/32149 Methods relating to embedding, encoding, decoding, detection or retrieval operations
• CPC Class Codes: H04N 1/32309 in colour image data
• CPC Class Codes: H04N 1/32352 Controlling detectability or arrangements to facilitate detection or retrieval of the embedded information, e.g. using markers for decoding, detection or retrieval operations H04N1/32149 and subgroups take 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

An image processing method is provided. This method comprises: a first information extraction step of extracting first information, including a registration signal used to correct the geometrical distortion of an image; a determination step of employing results obtained at the first information extraction step to determine whether second information is to be extracted from the image; a division step of dividing the image into at least one block; and a selection step of selecting the block. In this method, the first information and the second information are embedded in the image as invisible or less visible electronic watermarks, and are added to components of said image that are less easily discerned by a human'"'"'s eyes. Further, the amount of said first information is smaller than the amount of said second information, and the first information is embedded more deeply in the image than is the second information.

Claims

1. An image processing method comprising:

a first information extraction step of extracting first information, including a registration signal used to correct the geometrical distortion of an image; and

a determination step of employing the results obtained at said first information extraction step to determine whether second information is to be extracted from said image.

2. A method according to

claim 1

, wherein said first information and said second information are embedded in said image as invisible or less visible electronic watermarks.

3. A method according to

claim 1

, further comprising:

a division step of dividing said image into at least one block; and

a selection step of selecting said block.

4. A method according to

claim 1

, wherein said first information indicates that said image includes a specific image.

5. A method according to

claim 1

, wherein said second information is additional information.

6. A method according to

claim 1

, wherein said first information and said second information are added to components of said image that are less easily discerned by a human'"'"'s eyes.

7. A method according to

claim 1

, wherein said first information is information used to identify a paper currency, securities, a copyrighted image or others.

8. A method according to

claim 4

, wherein said specific image is a paper currency, and said second information indicates at least either an issuance country or the value of said paper currency.

9. A method according to

claim 4

, further comprising:

a determination step of determining whether said specific image is included,

wherein, when said specific image is included, an image process is performed based on said image.

10. A method according to

claim 1

, wherein said method is performed by a printer driver.

11. A method according to

claim 1

, wherein the amount of said first information is smaller than the amount of said second information.

12. A method according to

claim 1

, wherein the embedment depth of said first information relative to said image is greater than the embedment depth of said second information.

13. A method according to

claim 1

, wherein the time required for the extraction of said first information is shorter than the time required for the extraction of said second information.

14. A method according to

claim 1

, wherein the number of sets of said first information present in the unit area is greater than the number of sets of said second information.

15. An image processing method comprising:

an input step of inputting image data;

a block division step of dividing said image data into at least one first block, and at least one second block;

a block selection step of selecting said first block, and selecting said second block;

a first information extraction step of extracting first information from said first block that is selected;

an information extraction judgement step of employing said first information to determine whether second information is to be extracted;

a second information extraction step of extracting said second information from said selected second block in accordance with the determination at said information extraction judgement step; and

a control step of controlling an apparatus in accordance with the result obtained at said second information extraction step.

16. A method according to

claim 15

, wherein said first information and said second information are embedded as electronic watermark information.

17. A method according to

claim 15

, wherein the amount of said first information is smaller than the amount of said second information.

18. A method according to

claim 15

, wherein the embedment depth of said first information relative to said image is greater than the embedment depth of said second information.

19. A method according to

claim 15

, wherein the number of said first blocks is greater than the number of said second blocks.

20. A method according to

claim 15

, further comprising:

a re-extraction judgement step of employing the results obtained at said information extraction judgement step to determine whether said first information is to be re-extracted.

21. A method according to

claim 20

, wherein, at said re-extraction judgement step, whether said first information is to be re-extracted is determined in accordance with the number times said first information extraction step is performed.

22. A method according to

claim 15

, further comprising:

a color spatial transformation step of employing the determination at said information extraction judgement step to perform a color spatial transformation, or a tone transformation step of employing the determination at said information extraction judgement step to perform a tone transformation.

23. A method according to

claim 15

, wherein said first information is one-bit electronic watermark information indicating a specific image is included.

24. An image processing method comprising:

a first information extraction step of extracting, from an image, first information indicating that said image is a specific image; and

a determination step of employing the results obtained at said first information extraction step to determine whether second information, which is additional information for said specific image, is to be extracted from said image.

25. A method according to

claim 24

, wherein said first information and said second information are embedded in said image as invisible or less visible electronic watermarks.

26. A method according to

claim 24

, further comprising:

a division step of dividing said image into at least one block; and

a selection step of selecting at least one block.

27. A method according to

claim 24

, wherein the amount of said first information is smaller than the amount of said second information.

28. A method according to

claim 24

, wherein the embedment depth of said first information relative to said image is greater than the embedment depth of said second information.

29. A method according to

claim 24

, wherein the time required for the extraction of said first information is shorter than the time required for the extraction of said second information.

30. A method according to

claim 24

, wherein said specific image is an image of a paper currency or securities.

31. A method according to

claim 24

, wherein said first information and said second information are added to components of said image that are less easily discerned by a human'"'"'s eyes.

32. A method according to

claim 24

, wherein said first information is information used to identify a paper currency or securities.

33. A method according to

claim 24

, wherein said specific image is a paper currency, and said second information indicates at least either an issuance country or the value of said paper currency.

34. A method according to

claim 24

, further comprising:

a determination step of determining whether said specific image is included,

wherein, when said specific image is included, an image process is performed based on said image.

35. A method according to

claim 24

, which is performed by a printer driver.

36. A method according to

claim 24

, wherein the number of sets of said first information present in the unit area is greater than the number of sets of said second information.