Image processing apparatus and image processing method

Patent metadata

Field	Value
Publication number	US-2019287228-A1
Application number	US-201916432162-A
Country	US
Kind code	A1
Filing date	Jun 5, 2019
Priority date	Dec 12, 2016
Publication date	Sep 19, 2019
Grant date	—

Abstract

The present invention allows to estimate a continuous surface that defines a boundary surface of an object using image data, even if the image data was acquired by an imaging method in which image information on the boundary surface of the object is limited. An image processing apparatus according to the present invention includes a calculating unit that calculates a brightness gradient of a voxel group constituting volume data which represents a reconstructed image, and an estimating unit that estimates by using the brightness gradient a continuous surface which defines a boundary surface of an object corresponding to the volume data.

First claim

What is claimed is:

1 . An image processing apparatus comprising:
a calculating unit that calculates a brightness gradient of a voxel group constituting volume data which represents a reconstructed image; and an estimating unit that estimates by using the brightness gradient a continuous surface which defines a boundary surface of an object corresponding to the volume data.

2 . The image processing apparatus according to claim 1 , further comprising:
a display control unit that displays the continuous surface superimposed on the volume data.

3 . The image processing apparatus according to claim 1 , further comprising:
a display control unit that changes a brightness magnification, which is used for displaying the brightness value of each voxel, in accordance with the depth from the continuous surface.

4 . The image processing apparatus according to claim 3 , wherein
the display control unit changes the brightness magnification so that all the displayed brightness values of the voxels located in a shallow region are smaller than the maximum value of the displayed brightness values of the voxels located in a deep region.

5 . The image processing apparatus according to claim 1 , wherein
the estimating unit applies a physical model, which allows a lattice point group, formed by mutually connecting each lattice point having mass via springs, to freely fall from an area above the object due to gravity, to the distribution of the brightness gradient, so as to estimate the continuous surface.

6 . The image processing apparatus according to claim 5 , wherein
the estimating unit determines the normal direction of each voxel based on the distribution of the brightness gradient, and uses the normal direction as a direction of resistance that acts on the physical model.

7 . The image processing apparatus according to claim 1 , wherein
the estimating unit estimates the continuous surface by processing the voxels having a brightness value exceeding a noise level determined in advance.

8 . The image processing apparatus according to claim 7 , wherein
the estimating unit receives specification of the noise level via an input field disposed on a user interface screen.

9 . The image processing apparatus according to claim 1 , further comprising:
a display control unit that displays a button, to remove high brightness voxels existing in a deep region of the volume data from the display target, on a user interface screen.

10 . The image processing apparatus according to claim 1 , wherein
the volume data is one of photo-acoustic tomographic image data, ultrasonic image data and MRI angiographic image data.

11 . The image processing apparatus according to claim 1 , wherein
in the case when the voxels constituting the volume data are rearranged in descending order of brightness value, and the ratio of a voxel set on the lower brightness side to the entire volume data is a predetermined value or less, the estimating unit determines the brightness gradient for brightness values normalized by the maximum brightness value in the voxel set.

12 . The image processing apparatus according to claim 11 , wherein
the predetermined value is a value that is at least 99% and not more than 99.99%.

13 . The image processing apparatus according to claim 1 , having a function to display the object, with changing the chromaticity of the voxels in the direction from the continuous surface, which defines the boundary surface of the object, to inside the object.

14 . The image processing apparatus according to claim 5 , wherein
the estimating unit acquires information that indicates the imaged region, and sets at least one of the mass of the lattice point and the length of the spring based on the information that indicates the imaged region.

15 . An image processing apparatus, comprising:
a unit that acquires image data of an object including a structure; a unit that acquires information which indicates the position of the structure by image processing on the image data; and a unit that estimates a boundary surface of the object by processing using the information which indicates the position of the structure.

16 . The image processing apparatus according to claim 15 , wherein
the unit that estimates the boundary surface applies a physical model, which allows a lattice point group, formed by mutually connecting each lattice point having mass via springs, to freely fall from an area above the object due to gravity, to the distribution of the brightness gradient, so as to estimate the continuous surface.

17 . An image processing method, comprising:
processing that acquires image data of an object including a structure; processing that acquires information which indicates the position of the structure by image processing on the image data; and processing that estimates a boundary surface of the object using the information which indicates the position of the structure.

18 . The image processing method according to claim 17 , wherein
the processing that estimates the boundary surface applies a physical model, which allows a lattice point group, formed by mutually connecting each lattice point having mass via springs, to freely fall from an area above the object due to gravity, to the distribution of the brightness gradient, so as to estimate the continuous surface.

19 . A non-transitory computer readable storage medium having a program stored therein, the program allowing a computer to execute the image processing method according to claim 17 .

Assignees

• Canon Kk

Inventors

• Sekiguchi Hiroyuki
• Umezawa Kohtaro

Classifications

• G06T2210/41

  Medical · CPC title

• G06T2200/24

  involving graphical user interfaces [GUIs] · CPC title

• G06T19/00

  Manipulating three-dimensional [3D] models or images for computer graphics · CPC title

• G06T2207/10132

  Ultrasound image · CPC title

• G06T2207/20092

  Interactive image processing based on input by user · CPC title