Clustered aperiodic mask
Patent 5917951 Issued on June 29, 1999. Estimated Expiration Date: 
October 3, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
October 3, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMethod and apparatus for halftone rendering of a gray scale image using a blue noise mask Digital halftoning space filling curves Patent #: 5602943 InventorsApplicationNo. 943881 filed on 10/03/1997US Classes:382/237, Gray level to binary coding358/3.19, Stochastic or random dithering382/205Local neighborhood operations (e.g., 3x3 kernel, window, or matrix operator)ExaminersPrimary: Lee, Thomas C.Attorney, Agent or FirmInternational ClassesG06K 009/36G06K 009/46 H04N 001/40 AbstractA technique combines most of the advantages of both blue noise and clustering in generating a clustered aperiodic mask and using it in a dither array algorithm for halftoning. The method of halftoning of grey scale images utilizes a pixel-by-pixel comparison of the image against a clustered aperiodic mask in which the clustered aperiodic mask is comprised of a partly random and partly deterministic single valued function which is designed to produce visually pleasing dot configurations when thresholded at any level of grey. | |
