The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 28, 2010
Filed:
Jul. 21, 2006
Josh Star-lack, Palo Alto, CA (US);
Hassan Mostafavi, Los Altos, CA (US);
John Pavkovich, Palo Alto, CA (US);
Josh Star-Lack, Palo Alto, CA (US);
Hassan Mostafavi, Los Altos, CA (US);
John Pavkovich, Palo Alto, CA (US);
Varian Medical Systems, Inc., Palo Alto, CA (US);
Abstract
In one example of an embodiment of the invention, a method to correct for ring artifacts in an image is disclosed. A first Cartesian image is reconstructed based on data received from an imaging device, and the first Cartesian image is transformed into a first polar image. A first low-pass filter is applied to the first polar image, in the radial dimension, to form a second polar image, and the second polar image is subtracted from the first polar image to generate a third polar image. A second low-pass filter is applied to the third polar image, in an angular dimension, to form a fourth polar image, and the fourth polar image is transformed to Cartesian coordinates to form a second Cartesian image. The first Cartesian image is corrected based, at least in part, on the second Cartesian image.