System and method for detecting internal structures contained within the interior region of a solid object

• US 5,166,876 A
• Filed: 01/16/1991
• Issued: 11/24/1992
• Est. Priority Date: 01/16/1991
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Cline, Harvey E., Lorensen, William E.
• Primary Examiner(s): Weinhardt, Robert
• Assistant Examiner(s): Huntley, David
• Application Number:
  US07/641,615
• Time in Patent Office: 678 Days
• Field of Search: 382/9, 382/22, 382/26, 382/6, 340/729, 395/124, 364/413.13, 364/413.14, 364/413.22
• US Class Current: 345/424
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects

Abstract

In a method and apparatus for detecting and displaying arbitrary interior surfaces of a three-dimensional body from a regular array of values of at least one physical property in the interior of the body, the physical property measurements are made with systems such as computerized tomographic x-ray imaging, or magnetic resonance imaging. A recursive algorithm starts with a seed voxel in the surface of interest and continues to all adjacent voxels having a common face which is penetrated by the surface of interest. The common surface penetrations are derived from a look-up table which lists the adjacent voxels having a common penetrated face for each voxel index. The voxel index, in turn, is the string of binary digits representing the voxel vertices whose vertex values exceed the surface value of the surface of interest. The resulting list of voxels can be processed by conventional processors to display the surface of interest with greatly reduced interference from nearby, closely intermingled surfaces with the same or similar surface values.

Claims

1. A system for displaying a two-dimensional image of an internal surface in a three-dimensional solid body, said system comprising:

means for storing three-dimensional signal patterns representing a value for at least one physical property associated with a three-dimensional body at regularly spaced grid locations defining voxel elements within said body;

means for selectively accessing eight values of said physical property defining one of said voxel elements from said storing means;

means for storing common face penetration information concerning possible intersections of voxels with a surface of interest;

means for generating a voxel index of surface penetration of a voxel, said voxel index comprising a binary string representing whether each voxel vertex is within or outside of said surface of interest;

means for utilizing said voxel index to access said common face penetration information;

means for utilizing said stored common face penetration information to recursively identify only voxels intersecting said surface of interest so as to avoid bridging between said surface of interest and other closely intermingled but unconnected surfaces having similar surface physical property values; and

means for utilizing the identified voxels to display said two-dimensional image of said internal surface.

2. The system according to claim 1 wherein said voxel index generating means comprises means for simultaneously comparing all vertex values of said voxel to a value of said physical property indicative of said surface of interest.

3. A method for displaying a two-dimensional image of an internal surface within a three-dimensional solid body, said method comprising the steps of:

storing three-dimensional signal patterns representing the value of at least one physical property associated with a three-dimensional body at regularly spaced grid locations defining voxel elements within said body, each voxel having eight vertex values;

selectively accessing the eight voxel vertex values of said physical property for a stored one of said voxel elements;

storing common face penetration information concerning possible intersections of voxels with a surface of interests;

generating an index of surface penetration for each voxel, said index comprising a binary string representing which voxel vertex values are inside of said internal surface and which voxel vertex values are outside of said internal surface;

accessing common face penetration information associated with the corresponding voxel in accordance with the generated indices so as to avoid bridging between said surface of interest and other unconnected but closely intermingled surfaces having similar physical properties;

recursively identifying only those voxels having common faces penetrated by said internal surface; and

displaying a two-dimensional image of said internal surface by utilizing only the identified voxels.

4. The method according to claim 3 wherein said step of generating an index includes the step of simultaneously comparing all of said voxel vertex values to a single value representing said internal surface.