Image processing device, image processing method, and computer readable recording device

Patent metadata

Field	Value
Publication number	US-9349185-B2
Application number	US-201213597876-A
Country	US
Kind code	B2
Filing date	Aug 29, 2012
Priority date	Aug 31, 2011
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

An image processing device includes: a non-target region detecting unit that detects a region that is not to be examined as a non-target region from an image; a pixel-of-interest region setting unit that sets a pixel-of-interest region in a predetermined area including a pixel-of-interest position in the image; a surrounding region determining unit that determines a surrounding region, which is an area for acquiring information for use in forming a reference plane with respect to the pixel-of-interest position, based on the non-target region; a reference plane forming unit that forms the reference plane based on the information in the surrounding region; and an outlier pixel detecting unit that detects an outlier pixel having a pixel value numerically distant from circumferential values based on a difference between corresponding quantities of the reference plane at each pixel position and of the original image.

First claim

What is claimed is:

1. An image processing device comprising:
a processor comprising hardware, the processor implementing:
a non-target region detecting unit that detects a region that is not to be examined as a non-target region from an image;
a pixel-of-interest region setting unit that sets a pixel-of-interest region in a predetermined area including a pixel-of-interest position in the image;
a surrounding region determining unit that determines a surrounding region, which is an area for acquiring information for use in forming a reference plane with respect to the pixel-of-interest position, based on a positional relationship between the non-target region and the pixel-of-interest position, wherein the positional relationship further includes a boundary passing through the non-target region and the pixel-of-interest position, the boundary defining the area for acquiring information to include the pixel-of-interest position and not exceed the non-target region in the pixel-of-interest region as the surrounding region;
a reference plane forming unit that forms the reference plane based on the information in the surrounding region; and
an outlier pixel detecting unit that detects an outlier pixel having a pixel value numerically distant from circumferential values based on a difference between corresponding quantities of the reference plane at each pixel position and of the original image.

2. The image processing device according to claim 1 , wherein the surrounding region determining unit determines the surrounding region depending on classification of the non-target region.

3. The image processing device according to claim 2 , wherein the surrounding region determining unit includes:
a classifying unit that classifies the non-target region; and
a classificatory surrounding region determining unit that determines the surrounding region by a method set depending on the classification of the non-target region.

4. The image processing device according to claim 3 , wherein the classifying unit includes a continuity judging unit that judges continuity between a circumferential region of the non-target region and the non-target region.

5. The image processing device according to claim 4 , wherein the continuity judging unit forms an approximate plane that approximates information in the circumferential region of the non-target region, and judges the continuity by comparing corresponding quantities of the approximate plane and of the image.

6. The image processing device according to claim 4 , wherein the continuity judging unit judges the continuity based on a smoothed image that is the pixel-of-interest region smoothed based on information in the non-target region and the circumferential region of the non-target region.

7. The image processing device according to claim 4 , wherein the classificatory surrounding region determining unit includes a switching unit that switches a method of determining the surrounding region depending on presence or absence of the continuity.

8. The image processing device according to claim 3 , wherein the classifying unit includes a category classifying unit that classifies the non-target region into a plurality of categories depending on a method of detecting the non-target region.

9. The image processing device according to claim 8 , wherein the categories include at least one of shadow, blood vessel, groove, bubble, and halation.

10. The image processing device according to claim 3 , wherein the classificatory surrounding region determining unit includes a switching unit that switches a method of determining the surrounding region depending on a category of the non-target region.

11. The image processing device according to claim 3 , wherein the surrounding region determining unit further includes a correcting unit that corrects information in the non-target region and the circumferential region of the non-target region.

12. The image processing device according to claim 11 , wherein the correcting unit interpolates the information based on an average value of the information in the circumference of the non-target region.

13. The image processing device according to claim 11 , wherein the correcting unit interpolates the information based on a function approximation using the information in the circumference of the non-target region.

14. The image processing device according to claim 1 , wherein the reference plane forming unit forms the reference plane by calculating a weighted average of the information in the surrounding region using weighting factors corresponding to distances between the non-target region and the surrounding region.

15. The image processing device according to claim 1 , wherein the reference plane forming unit forms the reference plane by function approximation based on the information in the surrounding region.

16. The image processing device according to claim 1 , wherein the reference plane forming unit forms the reference plane by morphological operations with respect to the information in the surrounding region.

17. An image processing method comprising:
detecting a region that is not to be examined from an image as a non-target region;
setting a pixel-of-interest region in a predetermined area including a pixel-of-interest position in the image;
determining a surrounding region that is an area for acquiring information used for forming a reference plane with respect to the pixel-of-interest position, based on a positional relationship between the non-target region and the pixel-of-interest position, wherein the positional relationship further includes a boundary passing through the non-target region and the pixel-of-interest position, the boundary defining the area for acquiring information to include the pixel-of-interest position and not exceed the non-target region in the pixel-of-interest region as the surrounding region;
forming the reference plane based on the information in the surrounding region; and
detecting an outlier pixel having a pixel value numerically distant from circumferential values based on a difference between corresponding quantities of the reference plane at each pixel position and of the original image.

18. A non-transitory computer readable recording medium with an executable program stored thereon, wherein the program instructs a processor to perform:
detecting a region that is not to be examined from an image as a non-target region;
setting a pixel-of-interest region in a predetermined area including a pixel-of-interest position in the image;
determining a surrounding region that is an area for acquiring information used for forming a reference plane with respect to the pixel-of-interest position, based on a positional relationship between the non-target region and the pixel-of-interest position, wherein the positional relationship further includes a boundary passing through the non-target region and the pixel-of-interest position, the boundary defining the area for acquiring information to include the pixel-of-interest position and not exceed the non-target region in the pixel-of-interest region as the surrounding region;
forming the reference plane based on the information in the surrounding region; and
detecting an outlier pixel having a pixel value numerically distant from circumferential values based on a difference between corresponding quantities of the reference plane at each pixel position and of the original image.

Assignees

• Kono Takashi
• Kanda Yamato
• Kitamura Makoto
• Matsuda Takehiro
• Hirota Masashi
• Olympus Corp

Inventors

• Kono Takashi
• Kanda Yamato
• Kitamura Makoto
• Matsuda Takehiro
• Hirota Masashi

Classifications

• G06T7/0012 Primary

  Biomedical image inspection · CPC title

• G06K9/00147

  Physics · mapped topic

• G06T7/0081 Primary

  Physics · mapped topic

• G06T5/002

  Physics · mapped topic

• G06V20/698

  Matching; Classification · CPC title