Method and apparatus for visualizing 3D image data from tomographic imaging modalities

• US 20090189889A1
• Filed: 01/08/2009
• Published: 07/30/2009
• Est. Priority Date: 01/10/2008
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Engel, Klaus, Rottger, Stefan
• Granted Patent: US 8,264,485 B2
• Time in Patent Office: Days
• US Class Current: 345/419
• CPC Class Codes: G03B 42/02 using X-rays
• CPC Class Codes: G06T 15/06 Ray-tracing

Abstract

At least one embodiment of the present invention relates to a method and an apparatus for visualizing 3D image data from tomographic imaging modalities using a rendering technique in which every pixel is calculated by integrating or summing along respectively one ray through a volume surrounded by the 3D image data. In the method, a peeling function is additionally introduced into the integration or summation, by which, in the integration or summation, the 3D image data on the respective ray only contributes with its full data value to reducing the optical transparency beyond a prescribable value of an optical skin depth. The peeling function is selected such that, in a transition region before the prescribable value of the optical skin depth is reached, the 3D image data on the ray still contributes to reducing the optical transparency with a fraction of its full data value such that there is a smooth profile, generated by the peeling function, when an outer layer is peeled off. The method and the associated apparatus make it possible to avoid image artifacts such as pixel flickering during volume visualization.

Claims

1. A method for visualizing 3D image data from tomographic imaging modalities using a rendering technique in which every pixel is calculated by integrating or summing along respectively one ray through a volume surrounded by the 3D image data, the method comprising:

additionally introducing a peeling function into the integration or summation, by which, in the integration or summation, the 3D image data on a respective ray only contributes with its full data value to reducing the optical transparency beyond a prescribable value of an optical skin depth; and

selecting the peeling function such that, in a transition region before the prescribable value of the optical skin depth is reached, the 3D image data on the ray still contributes to reducing the optical transparency with a fraction of its full data value such that there is a smooth profile, generated by the peeling function, when an outer layer is peeled off.

2. The method as claimed in claim 1, wherein the peeling function PF(d) is selected as a function of the optical skin depth d(l) such that PF(d)=min(d/c;

1)^1/e, wherein c corresponds to the prescribable value of the optical skin depth and e corresponds to a prescribable value generating a smooth profile.

3. The method as claimed in claim 1, wherein a volume rendering technique is used.

4. The method as claimed in claim 1, wherein a gradient magnitude rendering technique is used.

11. The method as claimed in claim 2, wherein a volume rendering technique is used.

12. The method as claimed in claim 2, wherein a gradient magnitude rendering technique is used.

5. An apparatus for visualizing 3D image data from tomographic imaging modalities using a rendering technique in which every pixel is calculated by integrating or summing along respectively one ray through a volume surrounded by the 3D image data, comprising:

a storage device to store the 3D image data; and

a computational unit to carry out the integration or summation, wherein the computational unit is designed to additionally include a peeling function in the integration or summation, by which, in the integration or summation, the 3D image data on a respective ray only contributes with its full data value to reducing the optical transparency beyond a prescribable value of an optical skin depth, wherein the peeling function is selected such that, in a transition region before the prescribable value of the optical skin depth is reached, the 3D image data on the ray still contributes to reducing the optical transparency with a fraction of its full data value such that there is a smooth profile, generated by the peeling function, when an outer layer is peeled off.

6. The apparatus as claimed in claim 5, wherein the peeling function PF(d) is selected as a function of the optical skin depth d(l) such that PF(d)=min(d/c;

1)^1/e, wherein c corresponds to the prescribable value of the optical skin depth and e corresponds to a prescribable value generating a smooth profile.

7. The apparatus as claimed in claim 5, wherein a volume rendering technique is used.

8. The apparatus as claimed in claim 5, wherein a gradient magnitude rendering technique is used.

9. The apparatus as claimed in claim 6, wherein a volume rendering technique is used.

10. The apparatus as claimed in claim 6, wherein a gradient magnitude rendering technique is used.