Abstract: Disclosed are adaptive loop filtering techniques for video encoding and/or decoding. For a video unit, the encoder selects a set of predefined filters or generates a set of new filters, and places into the bitstream information identifying the set of predefined filters, or information defining the set of new filters. The set of filters may be used for loop filtering of at least one of the reconstructed samples of the video unit. At the decoder, a set of filters may be obtained by, decoding an index that identifies a set of predefined filters, or by decoding information related to a set of new filters. The obtained set of filters may be used for loop filtering of at least one decoded and reconstructed sample of the video unit.

Abstract: Disclosed are adaptive loop filtering techniques in the context of video encoding and/or decoding. For each video unit, the encoder can select a filter shape, and can place into the bitstream information that identifies the filter shape. At least one filter whose shape is the selected filter shape is used to loop filter at least one sample. At the decoder, a filter shape is obtained by decoding information that identifies the filter shape. At least one filter whose shape is the obtained filter shape is used to loop filter at least one reconstructed sample. Different filter shapes are also disclosed.

Abstract: Disclosed are techniques for adaptive interpolation filtering of luminance and chrominance samples in the context of motion compensation in video encoding or decoding. A two-dimensional interpolation filter of n×m coefficients may be separable, i.e., it may be separated into two one-dimensional filters with m and n coefficients, respectively. The bitstream may include, per video unit and sub-sample position, information indicating whether to use a newly-generated, a cached, or a default filter that may be a separable two-dimensional filter. The information may be structured in a way that takes advantage of the two-dimensional filter being separable. When a newly-generated filter is signalled, the bitstream may contain information pertaining to the characteristics of the newly-generated filter, such as its coefficients. A decoder may fetch this information from the bitstream to create the filters which are applied to samples of the video unit. An encoder may create a bitstream as described.