Path proximity rendering

Patent metadata

Field	Value
Publication number	US-9754411-B2
Application number	US-67664108-A
Country	US
Kind code	B2
Filing date	Sep 11, 2008
Priority date	Sep 13, 2007
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

The invention relates to a system ( 100 ) for visualizing an object of interest comprised in a volume of an image dataset, the system comprising a path unit ( 110 ) for specifying a path in the volume of the image dataset on the basis of the object of interest, a location unit ( 120 ) for determining a location on a projection ray through the volume of the image dataset on the basis of the specified path, and a value unit ( 130 ) for computing a projected gray value corresponding to the projection rayon the basis of the determined location on the projection ray. Because the locations on the projection ray are determined based on the specified path for indicating the object of interest, the actual computation of the projection gray values may be designed and constructed to show gray values describing the object of interest while hiding gray values describing other objects, in particular occluding objects. Thus, the system of the invention is arranged for visualizing the object of interest at different viewing angles without occluding the object of interest.

First claim

The invention claimed is:

1. A system for visualizing an object of interest comprised in a volume of an image dataset, the system comprising:
a memory configured to store the volume of the image dataset; and
a processor configured to:
receive an input indicative of a path near the object of interest in the volume of the image dataset;
specify the path in the volume of the image dataset;
determine, for each point on each projection ray in the volume of the image dataset, a distance to the path;
determine, for each projection ray in the volume of the image dataset, a point with a shortest distance to the path as a point of interest;
create a viewing plane, which is orthogonal to the projection rays and the projection rays intersect and traverse through the viewing plane;
determine, for the point of interest of each projection ray in the volume of the image dataset, a distance to the viewing plane;
identify, for the point of interest of each projection ray in the volume of the image dataset, a gray value;
replace, for the point of interest of each projection ray in the volume of the image dataset, the gray value with a value of zero only in response to the gray value being below a predetermined threshold;
compute a projected gray value for each pixel at the viewing plane based on the distance to the viewing plane and the gray value; and
render the object of interest in the viewing plane using the computed projected gray values.

2. The system of claim 1 , wherein the processor, for each projection ray in the volume of the image dataset, determines a global minimum as the point of interest.

3. The system of claim 1 , wherein the processor, for each projection ray in the volume of the image dataset, determines local minima and selects a local minimum from the local minima as the point of interest.

4. The system of claim 1 , wherein the processor, for each projection ray in the volume of the image dataset, determines the point of interest from segments between two local minima.

5. The system of claim 1 , wherein the processor, for each projection ray in the volume of the image dataset, determines the point of interest based on all points on the ray with a distance below a predetermined threshold distance.

6. The system of claim 1 , wherein the processor determines the predetermined threshold based on a gray value of the object of interest.

7. The system of claim 1 , wherein the processor determines the predetermined threshold based on predetermined range around a gray value of the object of interest.

8. The system of claim 1 , wherein the processor determines the distance to the viewing plane based on a component of a vector from the point to a closest point on the path.

9. The imaging system according to claim 1 , wherein the volume of the image dataset is generated by one of a Computed Tomography imaging system; a Positron Emission Tomography imaging system; a Magnetic Resonance imaging system; a Single Photon Emission Computerized Tomography imaging system.

10. The imaging system according to claim 1 , wherein the processor renders the object of interest in the viewing plane using at least one of maximum intensity projection, minimum intensity projection, average intensity projection, digital volume rendering, or digital reconstructed radiograph.

11. The system of claim 1 , wherein, for each projection ray in the volume of the image dataset, local minima are determined and a local minimum from the local minima is selected as the point of interest.

12. The system of claim 1 , wherein, for each projection ray in the volume of the image dataset, the point of interest is determined from segments between two local minima.

13. The system of claim 1 , wherein, for each projection ray in the volume of the image dataset, the point of interest is determined based on all points on the ray with a distance below a predetermined threshold distance.

14. A computer-implemented method for visualizing an object of interest comprised in a volume of an image dataset, the computer-implemented method comprising:
storing the volume of the image dataset in a memory;
receiving an input indicative of a path near the object in the volume of the image dataset;
specifying the path in the volume of the image dataset;
determining, for each point on each projection ray in the volume of the image dataset, a distance to the path;
determining, for each projection ray in the volume of the image dataset, a point with a shortest distance to the path as a point of interest;
construct a viewing plane that is orthogonal to the projection rays and the projection rays interest and traverse through the viewing plane;
determining, for the point of interest of each projection ray in the volume of the image dataset, a distance to the viewing plane;
determining, for the point of interest of each projection ray in the volume of the image dataset, a reference gray value, wherein the reference gray value for the point of interest is replaced with a value of zero in response to the reference gray value being below a predetermined threshold and maintained in response to the reference gray value being equal to or greater than the predetermined threshold;
computing a projected gray value for each pixel of the viewing plane based on the distance to the viewing plane and the corresponding reference gray value; and
rendering the object of interest in the viewing plane using the computed projected gray values.

15. The computer-implemented method of claim 14 , wherein, for each projection ray in the volume of the image dataset, a global minimum is determined as the point of interest.

Assignees

• Geller Dieter
• Lehmann Helko
• Koninklijke Philips Nv

Inventors

• Geller Dieter
• Lehmann Helko

Classifications

• G06T12/00

  Tomographic reconstruction from projections · CPC title

• G06T15/08

  Volume rendering · CPC title

• G06T11/003

  Physics · mapped topic

• G06T19/00 Primary

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