Scalable video coding using base-layer hints for enhancement layer motion parameters

A scalable video encoder comprising:

• a processor;
• and
• an encoder configured to encode, using the processor, an enhancement layer signal of a video based on block-wise predictive coding that includes:
• gathering, for a current block of a frame of the enhancement layer signal, a set of enhancement layer motion parameter candidates from already reconstructed neighboring blocks of the frame, the reconstructed neighboring blocks neighboring the current block,
• gathering a set of one or more base layer motion parameters of a block of a base layer signal, the block of the base layer signal being collocated to the current block of the frame of the enhancement layer signal,
• enlarging the set of enhancement layer motion parameter candidates with one or more base layer motion parameters of the set of one or more base layer motion parameters or a scaled version thereof to obtain an extended motion parameter candidate set, each of the set of enhancement layer motion parameter candidates and the one or more base layer motion parameters or a scaled version thereof in the extended motion parameter candidate set is a separate element of the extended motion parameter candidate set, wherein the extended motion parameter candidate set is ordered depending on the base layer motion parameters,
• selecting one of the motion parameter candidates of the extended motion parameter candidate set based on a syntax element corresponding to the current block to be signaled in a data stream, the syntax element specifically indicating the one of the motion parameter candidates of the extended motion parameter candidate set to be selected for the current block,
• generating, by motion compensated prediction, a prediction of the current block of the enhancement layer signal using the selected one of the motion parameter candidates of the extended motion parameter candidate set, and
• obtaining a residual signal for the current block based on a difference of the current block and the prediction of the current block, wherein the residual signal and the syntax element are encoded into the data stream.

A non-transitory computer-readable medium for storing data associated with a video, comprising:

• a data stream stored in the non-transitory computer-readable medium, the data stream comprising encoded information associated with an array of information samples representing a spatially sampled portion of the video, the encoded information including a residual signal and a syntax element, wherein the data stream is obtained based on a plurality of operations including:
• encoding an enhancement layer signal of a video based on block-wise predictive coding that includes:
• gathering, for a current block of a frame of the enhancement layer signal, a set of enhancement layer motion parameter candidates from already reconstructed neighboring blocks of the frame, the reconstructed neighboring blocks neighboring the current block,
• gathering a set of one or more base layer motion parameters of a block of a base layer signal, the block of the base layer signal being collocated to the current block of the frame of the enhancement layer signal,
• enlarging the set of enhancement layer motion parameter candidates with one or more base layer motion parameters of the set of one or more base layer motion parameters or a scaled version thereof to obtain an extended motion parameter candidate set, each of the set of enhancement layer motion parameter candidates and the one or more base layer motion parameters or a scaled version thereof in the extended motion parameter candidate set is a separate element of the extended motion parameter candidate set, wherein the extended motion parameter candidate set is ordered depending on the base layer motion parameters,
• selecting one of the motion parameter candidates of the extended motion parameter candidate set based on a syntax element corresponding to the current block to be signaled in a data stream, the syntax element specifically indicating the one of the motion parameter candidates of the extended motion parameter candidate set to be selected for the current block,
• generating, by motion compensated prediction, a prediction of the current block of the enhancement layer signal using the selected one of the motion parameter candidates of the extended motion parameter candidate set, and
• obtaining a residual signal for the current block based on a difference of the current block and the prediction of the current block, wherein the residual signal and the syntax element are encoded into the data stream.