An encoding device evaluates a plurality of processing and/or post-processing algorithms and/or methods to be applied to a video stream, and signals a selected method, algorithm, class or category of methods/algorithms either in an encoded bitstream or as side information related to the encoded bitstream. A decoding device or post-processor utilizes the signaled algorithm or selects an algorithm/method based on the signaled method or algorithm. The selection is based, for example, on availability of the algorithm/method at the decoder/post-processor and/or cost of implementation. The video stream may comprise, for example, downsampled multiplexed stereoscopic images and the selected algorithm may include any of upconversion and/or error correction techniques that contribute to a restoration of the downsampled images.

When removing a block distortion occurring in a local decoded image, a loop filtering part 11 of an image coding device carries out a filtering process on each of signal components (a luminance signal component and color difference signal components) after setting the intensity of a filter for removing the block distortion for each of the signal components according to a coding mode (an intra coding mode or an inter coding mode) selected by a coding controlling part 1.

When removing a block distortion occurring in a local decoded image, a loop filtering part 11 of an image coding device carries out a filtering process on each of signal components (a luminance signal component and color difference signal components) after setting the intensity of a filter for removing the block distortion for each of the signal components according to a coding mode (an intra coding mode or an inter coding mode) selected by a coding controlling part 1.

Blocking artifacts at a block boundary between a block and a neighboring block in a video frame are reduced by calculating an offset based on pixel values of pixels in a line of pixels in the block and based on pixel values of pixels in a corresponding line of pixels in the neighboring block. The offset is added to the pixel value of the pixel closest to the block boundary in the line of pixels and is subtracted from the pixel value of the pixel closest to the block boundary in the corresponding line of pixels. The resulting deblocking filter has good low-pass characteristics and is efficient for reducing blocking artifact.

The present disclosure provides a video decoding apparatus including at least a decoder configured to decode information on a size of a current block from encoded data, transform information, an inverse transformer configured to reconstruct a residual block of the current block by inversely transforming the transform coefficients in units of the size of each of the transform blocks, a predictor configured to generate a predicted block by using an inter-prediction, an adder configured to reconstruct the current block by adding the residual block to the predicted block, and a filter configured to identify transform boundaries between the transform blocks in the reconstructed current block by using the size of each of the transform blocks determined based on both the size of the current block and the information on the transform type, and then perform deblocking-filtering on at least part of the transform boundaries.

When removing a block distortion occurring in a local decoded image, a loop filtering part 11 of an image coding device carries out a filtering process on each of signal components (a luminance signal component and color difference signal components) after setting the intensity of a filter for removing the block distortion for each of the signal components according to a coding mode (an intra coding mode or an inter coding mode) selected by a coding controlling part 1.

The described embodiments relate to methods and systems for detecting the blockiness of a video signal comprised of a number of pixels. The method includes the steps of determining if the pixel forms a part of at least one visible horizontal transition along a macroblock border, at least one visible vertical transition along a macroblock border, at least one flat area or at least one flat macroblock; calculating a horizontal border transitions count, a vertical border transitions count, a flat area count and a macroblock flat area count; and generating at least one blockiness indicator for the region of interest selected from the group consisting of a block border indicator, a flat area indicator and a flat block indicator, wherein the at least one blockiness indicator is based on at least one of the horizontal border transitions count, the vertical border transitions count, the flat area count and the macroblock flat area count.

A method of decoding video, the method including receiving and parsing a bitstream which includes encoded video; extracting encoded image data relating to a current picture, which image data is assigned to at least one maximum coding unit, information relating to a coded depth and an encoding mode for each of the at least one maximum coding unit, and filter coefficient information for performing loop filtering on the current picture, from the bitstream; decoding the encoded image data in units of the at least one maximum coding unit, based on the information relating to the coded depth and the encoding mode for each of the at least one maximum coding unit; and performing deblocking on the decoded image data relating to the current picture, and performing loop filtering on the deblocked data, based on continuous one-dimensional (1D) filtering.

The present disclosure relates to deblocking filtering, which may be advantageously applied for block-wise encoding and decoding of images or video signals. In particular, the present disclosure relates to an improved memory management in an automated decision on whether to apply or skip deblocking filtering for a block and to selection of the deblocking filter. The decision is performed on the basis of a segmentation of blocks in such a manner that memory usage is optimized. Preferably, the selection of appropriate deblocking filters is improved so as to reduce computational expense.

A method and system for determining blur in digital video due to high quantization adopted during encoding of an image. The image is preprocessed to filter the noise and an edge image is extracted from the preprocessed image. A gradient sign change is determined for each pixel of the edge image. A ringing metric is determined based on the gradient magnitude and the gradient sign change. Further, a blockiness metric is determined based on a block grid periodicity and offset that is determined based on block grid analysis of the edge image. Further, a perceptual blurriness metric is determined using a mean and kurtosis computed based on a gradient histogram analysis of the block grid analysed edge image. A composite blurring metric is determined based on the blockiness metric, the perceptual blurriness metric, and ringing metric.