Patent
Non-linear adaptive image filter for filtering noise such as blocking artifacts
TLDR
In this paper, a fuzzy logic process, pixel deltas, and dual ramp generators are used to determine the horizontal and vertical length of a processing window surrounding an image block boundary.Abstract:
A 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.read more
Citations
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Patent
Segmented layered image system
TL;DR: In this paper, a mask is generated from a document image to reduce an estimate of compression for the combined size of the mask and multiple layers of the document image, which can then be processed and compressed separately in order to achieve better compression of document image overall.
Patent
Adaptive de-blocking filtering apparatus and method for MPEG video decoder
TL;DR: In this paper, a post processing de-blocking filter includes a threshold determination unit for adaptively determining a plurality of threshold values according to at least differences in quantization parameters QPs of adjacent blocks in a received video stream and to a user defined offset (UDO) allowing the threshold levels to be adjusted according to the UDO value.
Patent
Signal adaptive filtering method, signal adaptive filter and computer readable medium for storing program therefor
Yung-Iyul Lee,HyunWook Park +1 more
TL;DR: In this article, a signal adaptive filtering method for reducing blocking effect and ringing noise is proposed, which is capable of filtering the image data through inverse quantization and inverse discrete cosine transform according to generated blocking information and ringing information.
Patent
Reducing blocking and ringing artifacts in low-bit-rate coding
TL;DR: In this article, a technique to reduce blocking and ringing artifacts in low bit-rate block-based video coding is applied to each reconstructed frame output from the decoder, where the predicted AC coefficients are used to classify each reconstructed block as either a low-activity or a high-activity block.
Patent
Method for reducing blocking artifacts
TL;DR: In this paper, a method for removing blocking artifacts from moving and still pictures, comprising classifying horizontal and vertical boundaries in each picture as blocky or non-blocky, is proposed.
References
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Journal ArticleDOI
Nonlinear space-variant postprocessing of block coded images
B. Ramamurthi,Allen Gersho +1 more
TL;DR: A new nonlinear, space-variant filtering algorithm is proposed which smooths jagged edges without blurring them, and smooths out abrupt intensity changes in monotone areas.
Journal ArticleDOI
Reduction Of Blocking Effects In Image Coding
Howard C. Reeve,Jae Lim +1 more
TL;DR: Two methods are developed to reduce the blocking effect when the image is reconstructed at the decoder due to discontinuities between the subimages in transform coding.
Patent
Apparatus and method for smoothing images
TL;DR: Improved spatial, temporal, and spatio-temporal noise reduction apparatus as discussed by the authors have been proposed for noise reduction in conjunction with edge enhancement, spatial interpolation, magnification adjustment by spatial interpolations, and dynamic range compression.
Journal ArticleDOI
Information loss recovery for block-based image coding techniques-a fuzzy logic approach
TL;DR: The proposed method, which is suitable for recovering both isolated and contiguous block losses, provides a new approach for error concealment of block-based image coding systems such as the JPEG coding standard and vector quantization-based coding algorithms.
Patent
Method and system for adapting a digitized signal processing system for block processing with minimal blocking artifacts
TL;DR: In this paper, a method and apparatus for processing n-dimensional digitized signals containing at least two adjacent blocks of digitized sample values is presented, where the digitized signal is transformed in accordance with a spatial transform operator, characterized by similar size blocks to the blocks in the input signal.