Apparatus and method for correcting object density in computed t

Details Apparatus and method for correcting object density in computed t Apparatus and method for correcting object density in computed t

1998-02-11

2000-08-22

Bruce, David Vernon

X-ray or gamma ray systems or devices

Specific application

Computerized tomography

378 15, 378 57, 378901, G01N 2304

Patent

active

061083968

ABSTRACT:
Sheet explosives can be detected by analyzing voxels surrounding a test voxel. If the density is sufficiently different, it is concluded that the test voxel is associated with a sheet object. Sheet objects can also be detected by eroding the CT data then subtracting from the original data, leaving only thin sheet-shaped objects. A connectivity process can be applied to voxels to combine them into objects after sheets are detected. A dilation function can then be performed to replace surface voxels. A corrected mass can be computed and compared to mass thresholds to classify the object as to whether it poses a threat. Multiple mass thresholds can be used. Bulk objects can be detected by a modified morphological connected components labeling (CCL) approach which performs a series of erosion and dilation steps to separate adjacent objects in the data such that they can be individually labeled and analyzed. A merging process can be used to reconnect related items, such as multiple sticks, that were separated during an erosion step. The merging process allows multiple objects that would individually pass as non-threat items to be combined into a single item that is correctly classified as a threat. The system can also identify objects that contain liquids, if desired.

REFERENCES:
patent: 4064440 (1977-12-01), Roder
patent: 4366382 (1982-12-01), Kotowski
patent: 4511799 (1985-04-01), Bjorkholm
patent: 4903202 (1990-02-01), Crawford
patent: 4905148 (1990-02-01), Crawford
patent: 5022062 (1991-06-01), Annis
patent: 5044002 (1991-08-01), Stein
patent: 5098640 (1992-03-01), Gozani et al.
patent: 5125015 (1992-06-01), Shimoni et al.
patent: 5182764 (1993-01-01), Peschmann et al.
patent: 5206592 (1993-04-01), Buess et al.
patent: 5233300 (1993-08-01), Buess et al.
patent: 5291402 (1994-03-01), Pfoh
patent: 5319547 (1994-06-01), Krug et al.
patent: 5479023 (1995-12-01), Bartle
patent: 5490218 (1996-02-01), Krug et al.
patent: 5600700 (1997-02-01), Krug et al.
patent: 5642393 (1997-06-01), Krug et al.
patent: 5642394 (1997-06-01), Rothschild
patent: 5699400 (1997-12-01), Lee et al.
patent: 5712926 (1998-01-01), Eberhard et al.
patent: 5754617 (1998-05-01), Itoh

Affiliated with

Also associated with

Rating

Apparatus and method for correcting object density in computed t does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus and method for correcting object density in computed t, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for correcting object density in computed t will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-589891