Mitsubishi Electric Research Laboratories, Inc.

Mitsubishi Denki Kabushiki Kaisha

Hao-Song Kong

Anthony Vetro

Huifang Sun

Yao Nie

Wei-Ying Kung

Ximin Zhang

Toshihiko Hata

Kenneth Eugen Barner

Naoki Kuwahara

A method reduces artifacts in an input image. A variance image is generated from the input image. The input image is partitioned into a plurality of blocks of pixels. A set of classifications is defined. The set of classifications includes smooth, texture, and edge. A particular classification is assigned to each block of pixels of the input image according to the variance image, to generate smooth blocks, texture blocks, and edge blocks. A fuzzy filter is applied to each pixel of only each edge block.

System and method for reducing ringing artifacts in images

A method transcodes an image in the form of an encoded input bitstream. The input bitstream includes quality layers, each quality layer includes a resolution levels, each resolution level includes components, each component includes precincts, and each precinct includes a packet partition location, a header length, and a body length. The input bitstream is decoded partially to obtain a structure of the encoded input bitstream. Coordinates of a region-of-interest in the image are specified, and progressive parameters are defined. The partially decoded input bitstream is then encoded according to the structure, the coordinates, and the progressive parameters to obtain an encoded output bitstream.

Image transcoding

A method filters pixels in an image, by first partitioning the image into blocks. Edge block are identified. A variance of an intensity for each pixel in each edge block is determined. Then, each pixel in each edge block is filtered with a filter that is dependant on the variance of the pixel.

System and method for filtering artifacts in images

A method conceals errors in an infra-frame of compressed video. The intra-frame is decoded to multiple macroblocks. Each macroblock including pixels arranged in a rectangular array. A lost macroblock is identified during the decoding. Pixels along an outer boundary of the lost macroblock are concealed from nearest candidate pixels along outer boundaries of macroblocks immediately adjacent to the lost macroblock. All other pixels in the lost macroblock are concealed from nearest candidate pixels selected from previously concealed pixels in the lost macroblock.

Error concealing decoding method of intra-frames of compressed videos

A method classifies pixels in an image by first partitioning the image into blocks. A variance of an intensity is determined for each pixel, and for each block the pixel with the maximum variance is identified. Then, the blocks are classified into classes according to the maximum variance.

System and method for classifying pixels in images

A method encodes an inter-frame of a compressed video, the inter-frame including multiple macroblocks in a predetermined order. Each macroblock has an associated motion vector. For each current macroblock in the predetermined order, a set of near macroblocks are identified. An index is assigned to each near macroblock. A difference between the motion vector of the current macroblock and the motion vector of each near macroblocks is determined. The indices of the near macroblocks are then sorted in order of the differences and appended to the inter-frame.

Error resilient encoding method for inter-frames of compressed videos

A method encodes a video by first measuring a variance of pixel intensities in a current frame. A number of bits to encode the current frame is assigned according to rate and buffer fullness constraints. A multiplier value is determined directly as a function of only the variance and the number of bits assigned to the current frame. Motion vectors between a reference frame and the current frame are estimated, and a sum of absolute difference (SAD) is based on a motion compensated residual between the reference frame and the current frame. An encoding mode is determined for each macro block in the current frame based on the sum of absolute difference, the motion vectors and the multiplier value. Then, the motion compensated residual is encoded based on the encoding mode, multiplier value and the number of allocated bits.

System and method for determining coding modes, DCT types and quantizers for video coding

A method and system transcodes an input video to a lower spatial resolution. The input video is first decoded into pictures. Each picture includes a set of macroblocks. Each picture sub-sampled to a downscaled picture having a lower spatial resolution. A quantization scale is selected for each macroblock in the downscaled picture. A set of motion vectors is generated for each macroblock in the downscaled picture. A multiplier value based on the quantization scale is determined for each macroblock in the downscaled picture. One of a plurality of encoding modes is selected for each macroblock in the downscaled picture according to the quantization scale, the motion vectors, and the multiplier value. Then, each macroblock in each downscaled picture is encoded according to the quantization scale, the selected encoding mode, and the set of motion vectors to produce an output video having a lower spatial resolution that the input video.

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Newton, MA, United States of America

Hao-Song Kong