Wisconsin Alumni Research Foundation

Ericsson Gmbh

Boston University

General Dynamics Information Technology, Inc.

Ac Capital Management, Inc.

Truong Q Nguyen

Yu Hen Hu

Joel A Rosiene

Leonid Krasny

Soontorn Oraintara

Seyfullah H Oguz

Trac D Tran

Roland T Chin

Hazem M Hajj

Seungjoon Yang

Damon L Tull

A method and apparatus is disclosed for efficiently encoding data representing a video image, thereby reducing the amount of data that must be transferred to a decoder. The method includes transforming data sets utilizing a tensor product wavelet transform which is capable of transmitting remainders from one subband to another. Collections of subbands, in macro-block form, are weighted, detected, and ranked enabling prioritization of the transformed data. A motion compensation technique is performed on the subband data producing motion vectors and prediction errors which are positionally encoded into bit stream packets for transmittal to the decoder. Subband macro-blocks and subband blocks which are equal to zero are identified as such in the bit stream packets to further reduce the amount of data that must be transferred to the decoder.

Apparatus and method for compressing video information

An apparatus for post-processing of decompressed images having ringing artifacts identifies edges of the image such as may generate such artifacts and defines zones outside of those edges but conforming thereto in which ringing artifacts are to be expected. These zones may be modified according to a model of the human visual system and then filtered so as to reduce ringing artifacts. The filtered zones are spliced back into the image minimizing unnecessary modification of the image while reducing ringing artifacts.

Method and apparatus for the reduction of artifact in decompressed images using morphological post-filtering

A method for signal detection uses a likelihood ratio derived from the received signal to produce an estimate of a speech signal that has been corrupted by noise during transmission. The received signal is input to a receiver filter and a voice-activity detector. The receiver filter filters the received signal to produce a filter output signal. The voice-activity detector generates a likelihood ratio based on the received signal, which is then used to produce a speech-probability estimate indicating the probability that the received signal includes a speech signal. The filter output signal is combined with the speech-probability estimate output from the voice-activity detector to generate a soft estimate of the original speech signal.

Soft decision signal estimation

A technique for post-processing decoded compressed images to reduce decoding-related artifacts employs a maximum likelihood estimation of an original image f. The decoded image is modeled as a montage of &ldquo;flat surfaces&rdquo; of different intensities, where the number of flat surfaces and their intensities are generally different in different regions of the decoded image. The intensity of each pixel is conditionally adjusted to that of a corresponding flat surface in a window region surrounding the pixel. In a general algorithm, the flat surface model is fitted to the observed image by estimating the model parameters using the &ldquo;k-means&rdquo; algorithm and a hierarchical clustering algorithm. A cluster similarity measure (CSM) is used to determine the number of intensity clusters, and hence flat surfaces, in the model of a window region surrounding a pixel of interest. The pixel intensity is adjusted to an estimated value which is the mean intensity of the cluster in which the pixel falls. A simplified version of the method employs a three-cluster model in which the cluster centers are initialized by a deterministic rule. This simplified method is non-iterative in nature, thus requiring fewer computational resources.

Image artifact reduction using maximum likelihood parameter estimation

An data compression technique combines the benefits of block-wise processing, such as allows reduced buffer memory usage and improved speed through parallel techniques, with tree-type compression normally associated with wavelet-type compression techniques. Block artifacts in the reconstructed data at the partitions between blocks are minimized by use of lapping transformations.

Image compression system using block transforms and tree-type

A detector system locates a feature in an input signal. The input signal is applied to a multiscale filter bank which produces a corresponding set of filtered signals that are applied to a multiscale detector. A scale space tree table is produced by the detector which indicates the location in each filtered signal where the feature is possibly located. A MAP correlator examines the scale space tree table to determine which indications therein are feature locations. One-dimensional and two-dimensional embodiments are described. In addition, the design framework is disclosed for extending a one scale filter to a multiscale filter, for designing a filter bank from the multiscale filter and for designing the MAP correlator dependent on the feature being located and the chosen filter bank.

Growing community of inventors

Burlington, MA, United States of America

Truong Q Nguyen