THREE-DIMENSIONAL IMAGE CONSTRUCTION APPARATUS AND THREE-DIMENSIONAL IMAGE CONSTRUCTION METHOD

• US 20150138187A1
• Filed: 07/30/2013
• Published: 05/21/2015
• Est. Priority Date: 08/02/2012
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi Medical Corporation (Hitachi, Ltd.)
• Inventors: Goto, Yoshihiro
• Granted Patent: US 9,750,473 B2
• Time in Patent Office: Days
• US Class Current: 345/419
• CPC Class Codes: A61B 6/466 adapted to display 3D data
• CPC Class Codes: G06T 15/00 3D [Three Dimensional] image rendering
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics
• CPC Class Codes: G06T 2207/10072 Tomographic images
• CPC Class Codes: G06T 2207/30004 Biomedical image processing
• CPC Class Codes: G06T 2219/008 Cut plane or projection plane definition

Abstract

A calculation unit generates a depth image corresponding to a first three-dimensional image with respect to a region of interest and sets a first image region based on a depth gradient of the depth image. The calculation unit moves the origin of a projection line to the near side or far side in the projection line direction by an amount of movement B for a pixel in the first image region, constructs a depth image based on the moved origin of the projection line in the first image region, sets a second image region based on the depth gradient of the depth image based on the moved origin of the projection line in the first image region, sets the second image region as the first image region, and repeats these processes. Once end conditions are satisfied, the calculation unit constructs a second three-dimensional image based on the moved origin of the projection line.

Claims

1. A three-dimensional image construction apparatus comprising:

a display unit displaying a first three-dimensional image on a predetermined origin surface;

an input unit receiving an input of a region of interest for a second three-dimensional image in the first three-dimensional image; and

a calculation unit setting the origin surface as an initial value of the origin of a projection line to construct the second three-dimensional image, correcting the origin of the projection line for a pixel in the region of interest based on a depth image corresponding to the first three-dimensional image, and then constructing the second three-dimensional image using the corrected origin of the projection line for the region of the interest.

2. The three-dimensional image construction apparatus according to claim 1,

wherein the calculation unit extracts a first image region based on a depth gradient of the depth image in the region of interest,

corrects the origin of the projection line for the pixel in the first image region to a direction opposite to a projection direction or the projection direction by a certain distance as the first step of repetitive processing and memorizes the corrected origin of the projection line in a storage unit,

extracts a second image region based on a depth gradient of the depth image on the basis of the corrected origin of the projection line as the second step of repetitive processing in the first image region,

determines whether the second image region satisfies end conditions or not as the third step of repetitive processing,

sets the second image region as the new first image region if the end conditions are not satisfied and repeats the third step from the first step until the end conditions are satisfied, and then

constructs the second three-dimensional image using the corrected origin of the projection line memorized in the storage unit for the region of the interest if the end conditions are satisfied.

3. The three-dimensional image construction apparatus according to claim 2,

wherein the end conditions are based on areas of the first image region and the second image region.

4. The three-dimensional image construction apparatus according to claim 2,

wherein the end conditions are based on only an area of the second image region.

5. The three-dimensional image construction apparatus according to claim 2,

wherein the calculation unit changes a determination value of the end conditions in a case where the corrected origin of the projection line exceeds a limit position.

6. The three-dimensional image construction apparatus according to claim 1,

wherein the input unit receives an input of two coordinates in the first three-dimensional image to be displayed on the display, and

the calculation unit determines the region of interest based on positions of the two coordinates and corrects the origin of the projection line for a pixel of the region of interest based on a pixel value of the depth image at the two coordinates.

7. The three-dimensional image construction apparatus according to claim 1,

wherein the input unit receives an input of two curves in the first three-dimensional image to be displayed on the display, and

the calculation unit determines the region of interest based on positions of the two curves and corrects the origin of the projection line for a pixel of the region of interest based on a pixel value of the depth image on the two curves.

8. The three-dimensional image construction apparatus according to claim 7,

wherein the calculation unit determines the region of interest by using either of a limit mode where the region of interest is limited to a region between the two curves or an extension mode where the region of interest is extended to the outside of a region between the two curves.

9. The three-dimensional image construction apparatus according to claim 7,

wherein the input unit receives an interruption and resume of a trace input while receiving the trace input of the curves, and

the calculation unit interpolates a pixel value of the depth image for a pixel between an interrupted position and a resume position of the trace input by using a pixel value of the depth image in the interrupted position and a pixel value of the depth image in the resume position.

10. The three-dimensional image construction apparatus according to claim 1,

wherein the calculation unit corrects the origin of the projection line for a pixel in the region of interest by performing threshold processing radially in a certain angle range with a projection direction centered from a pixel in the region of interest.

11. The three-dimensional image construction apparatus according to claim 1,

wherein the display unit displays a position of the corrected origin of the projection line with it superimposed on a tomographic image.

12. The three-dimensional image construction apparatus according to claim 1,

wherein the display unit displays a depth position of the depth image with it superimposed on a tomographic image.

13. A three-dimensional image construction method executing:

a step in which a display unit displays a first three-dimensional image on a predetermined origin surface;

a step in which an input unit receives an input of a region of interest for a second three-dimensional image in the first three-dimensional image;

a step in which a calculation unit sets the origin surface as an initial value of the origin of a projection line to construct a second three-dimensional image;

a step in which a calculation unit corrects the origin of the projection line for a pixel in the region of interest based on a depth image corresponding to the first three-dimensional image; and

a step in which a calculation unit constructs the second three-dimensional image using the corrected origin of the projection line for the region of interest.