Non-linear adaptive image filter for filtering noise such as blocking artifacts
Patent 6285801 Issued on September 4, 2001. Estimated Expiration Date: 
May 29, 2018. 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.
May 29, 2018. 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 system for adapting a digitized signal processing system for block processing with minimal blocking artifacts Method of reducing block artifacts created by block transform compression algorithms Fuzzy logic device for image noise reduction Apparatus and methods for smoothing images Adaptive postprocessing system for reducing blocking effects and ringing noise in decompressed image signals Patent #: 5883983 InventorsAssigneeApplicationNo. 087959 filed on 05/29/1998US Classes:382/268, Minimize discontinuities at boundaries of image blocks (i.e., reducing blocking effects or effects of wrap-around)348/445, Conversion between standards with different aspect ratios348/607, Noise or undesired signal reduction375/240.29, Pre/post filtering382/199, Pattern boundary and edge measurements382/205, Local neighborhood operations (e.g., 3x3 kernel, window, or matrix operator)382/206, Global features (e.g., measurements on image as a whole, such as area, projections, etc.)382/260, Image filter382/275Artifact removal or suppression (e.g., distortion correction)ExaminersPrimary: Rogers, Scott A.Attorney, Agent or FirmForeign Patent References
International ClassesG06K 009/40G06T 005/00 H04N 005/21 AbstractA filter reduces artifacts, such as grid noise and staircase noise, in block-coded digital images with image block boundaries. The type of filtering is determined after an estimation of the image global metrics and local metrics. For areas of the image near grid noise, the filter performs low pass filtering. For image fine details, such as edges and texture, no filtering is performed so that masking is avoided. The filter operates in intra-field mode and uses a fuzzy logic process, pixel deltas, and dual ramp generators to determine the horizontal and vertical length of a processing window surrounding an image block boundary.Other References
Field of SearchMinimize discontinuities at boundaries of image blocks (i.e., reducing blocking effects or effects of wrap-around)Image filter Artifact removal or suppression (e.g., distortion correction) Feature extraction Local or regional features Pattern boundary and edge measurements Local neighborhood operations (e.g., 3x3 kernel, window, or matrix operator) Global features (e.g., measurements on image as a whole, such as area, projections, etc.) Noise elimination Involving block coding Conversion between standards with different aspect ratios Progressive to interlace Noise or undesired signal reduction Block coding Pre/post filtering | |
