Image processing method and apparatus

Patent metadata

Field	Value
Publication number	US-9659405-B2
Application number	US-201514676056-A
Country	US
Kind code	B2
Filing date	Apr 1, 2015
Priority date	Apr 1, 2015
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

An image processing apparatus comprises data receiving circuitry for receiving a volumetric imaging data set which is representative of a volume, the volume comprising a region of interest and lighting circuitry configured to place a virtual light source outside the region of interest and to apply a lighting simulation process to simulate light from the virtual light source. The applying of the lighting simulation process is at least partially different for a first lighting region than for a second lighting region, the first lighting region comprising at least part of the volume outside the region of interest and the second lighting region comprising at least part of the region of interest.

First claim

The invention claimed is:

1. An image processing apparatus comprising
data receiving circuitry configured to receive a volumetric imaging data set which is representative of a volume, the volume comprising a region of interest; and
lighting circuitry configured to place a virtual light source outside the region of interest, and to apply a lighting simulation process to simulate light from the virtual light source;
wherein the applying of the lighting simulation process is at least partially different for a first lighting region than for a second lighting region, the first lighting region comprising at least part of the volume outside the region of interest and the second lighting region comprising at least part of the region of interest, and
wherein the lighting simulation process comprises casting a plurality of rays from the virtual light source and wherein, for each of the plurality of rays, applying the lighting simulation process is at least partially different for a first portion of the ray than for a second portion of the ray, wherein at least part of the first portion of the ray is within the first lighting region and at least part of the second portion of the ray is within the second lighting region, and
wherein applying the lighting simulation process for each ray comprises determining irradiance at each of a plurality of sample points along the second portion of the ray and at least one of a) and b):
a) calculating no irradiance for the first portion of the ray;
b) determining irradiance at each of a plurality of sample points along the first portion of the ray, wherein the irradiance is based on a reduced absorption.

2. An apparatus according to claim 1 , wherein the applying of the lighting simulation process is at least partially different for the first lighting region than for the second lighting region to ensure that at least one of a), b), c) and d);
a) at least some of the light from the virtual light source reaches the region of interest;
b) the illumination of the region of interest is increased;
c) a desired light level is achieved inside the region of interest;
d) the virtual light source illuminates at least one selected part of the region of interest.

3. An apparatus according to claim 1 , wherein the volumetric imaging data set is representative of a medical imaging scan of the volume.

4. An apparatus according to claim 3 , wherein the medical imaging scan comprises at least one of an ultrasound scan, a CT scan, an MR scan, a PET scan, a SPECT scan.

5. An apparatus according to claim 1 , wherein the region of interest comprises at least one of an interior anatomical structure, a body cavity, a duct, a vessel, a lumen, an airway, an air-filled region, a fluid-filled region.

6. An apparatus according to claim 1 , wherein applying the lighting simulation process in the first lighting region comprises at least one of a) or b):—
a) reducing absorption of the light within the first lighting region;
b) providing substantially no absorption of the light within the first lighting region.

7. An apparatus according to claim 1 wherein the first lighting region comprises a region between the virtual light source and the region of interest.

8. An apparatus according to claim 1 wherein the first lighting region includes a part of the region of interest.

9. An apparatus according to claim 1 wherein a boundary of the second lighting region is within the region of interest and is displaced from a boundary of the region of interest by an offset distance.

10. An apparatus according to claim 1 , wherein the applying of the lighting simulation process is varied gradually across a transition region between the first lighting region and the second lighting region, such that the lighting simulation process transitions gradually from the lighting simulation process for the first lighting region to the lighting simulation process for the second lighting region.

11. An apparatus according to claim 1 , further comprising rendering circuitry configured to render at least one image based on the simulated light.

12. An apparatus according to claim 11 , wherein the lighting circuitry is further configured to use the simulated light to generate an irradiance volume corresponding to the volumetric imaging data set, wherein the rendering circuitry is configured to render the at least one image at least partly based on the irradiance volume, and wherein at least one of the generation of the irradiance volume and the rendering of the image comprises at least one of: global illumination, photon mapping, light space volume traversal, deep shadow maps, half angle slicing, light propagation volumes, shadow propagation volumes.

13. An apparatus according to claim 11 , wherein the virtual light source comprises a virtual directional light source, the lighting circuitry is further configured to place a virtual point light source within the region of interest, and the rendering circuitry is configured to render an image based on both simulated light from the virtual point light source and simulated light from the virtual directional light source.

14. An apparatus according to claim 11 , wherein the at least one image comprises a series of images used to generate a flythrough view, and wherein a position of the virtual light source remains static with respect to the volume in each of the series of images.

15. An apparatus according to claim 11 , wherein the at least one image comprises a series of images used to generate a flythrough view, and wherein a position of the virtual light source with respect to the volume is different in at least some of the series of images.

16. An apparatus according to claim 11 , wherein the at least one image comprises an unfolded view.

17. An apparatus according to claim 11 , wherein the at least one image comprises at least one of a perspective projection, a fish-eye projection, an angular projection.

18. An apparatus according to claim 1 , wherein at least one of a) and b):
a) the lighting circuitry is configured to place the virtual light source at least one of 1) a selected angle or a predetermined angle, 2) a selected position or a predetermined position; and 3) a light direction relative to at least one of the region of interest and a virtual camera position;
b) the lighting circuitry is configured to place the virtual light source in response to user input.

19. An apparatus according to claim 1 , wherein the lighting circuitry is further configured to place at least one further virtual light source relative to the volume and, for the or each further virtual light source, to apply the lighting simulation process to simulate light from the further light source, wherein the applying of the lighting simulation process is at least partially different for a further at least part of the volume outside the region of interest than for a further at least part of the region of interest.

20. An apparatus according to claim 1 , wherein the volumetric imaging data set comprises data acquired using a contrast medium.

21. An image processing apparatus comprising
data receiving circuitry configured to receive a volumetric imaging data set which is representative of a volume, the volume comprising a region of interest; and
lighting circuitry configured to place a virtual light source outside the region of interest, and to apply a lighting simulation process to simulate light from the virtual light source;
wherein the applying of the lighting simulation process is at least partially

Assignees

• Toshiba Medical Sys Corp

Inventors

• Wahrenberg Magnus Fredrik

Classifications

• G06T15/506 Primary

  Illumination models · CPC title

• G06T15/08

  Volume rendering · CPC title

• G06T2207/30004

  Biomedical image processing · CPC title

• G06T2210/41

  Medical · CPC title

• A61B8/5215

  involving processing of medical diagnostic data · CPC title