An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may comprise determining a motion vector and decoding a current block based on the motion vector. The motion vector may be determined based on at least one of a first reference picture type of a first reference picture corresponding to the current block or a second reference picture type of a second reference picture corresponding to an inter-layer corresponding block.

Methods and devices are provided for encoding a video stream which comprise encoding a plurality of frames of video acquired from different points of view, generating statistical values for the frames of video determined from values of pixels of the frames, generating, for each of the plurality of frames, a perceptual hash value based on statistical values of the frame and encoding a current frame comprising video acquired from a corresponding one of the different points of view using a previously encoded reference frame based on a similarity of perceptual hashes of the current frame and the previously encoded reference frame.

The techniques of this disclosure may be generally related to reference statues of pictures. The techniques may store the reference status information of reference pictures of a picture, at an instance when the picture is being coded. The techniques may then utilize the reference status information of the reference pictures of the picture, at the instance when the picture was coded, to inter-predict video blocks of a subsequent picture.

The techniques of this disclosure may be generally related to reference statues of pictures. The techniques may store the reference status information of reference pictures of a picture, at an instance when the picture is being coded. The techniques may then utilize the reference status information of the reference pictures of the picture, at the instance when the picture was coded, to inter-predict video blocks of a subsequent picture.

A system for decoding a video bitstream includes receiving a reference picture set associated with a frame including a set of reference picture identifiers. The reference picture set identifies one or more reference pictures to be used for inter-prediction of the frame based upon its associated least significant bits of a picture order count based upon the reference picture identifiers. The one or more reference pictures is a second or greater previous frame to the frame having the matching reference picture identifier.

A system for decoding a video bitstream includes receiving a reference picture set associated with a frame including a set of reference picture identifiers. The reference picture set identifies one or more reference pictures to be used for inter-prediction of the frame based upon its associated least significant bits of a picture order count based upon the reference picture identifiers. The one or more reference pictures is a second or greater previous frame to the frame having the matching reference picture identifier.

Various schemes for managing search memory are described, which are beneficial in achieving enhanced coding gain, low latency, and/or reduced hardware for a video encoder or decoder. In processing a current block of a current picture, an apparatus determines a quantity of a plurality of reference pictures of the current picture. The apparatus subsequently determines, for at least one of the reference pictures, a corresponding search range size based on the quantity. The apparatus then determines, based on the search range size and a location of the current block, a search range of the reference picture, based on which the apparatus encodes or decodes the current block.

An apparatus is provided and includes processing circuitry that determines a plurality of first sub-block motion vectors for a plurality of sub-blocks of a current block. The processing circuitry determines a plurality of second sub-block motion vectors by respectively constraining the plurality of first sub-block motion vectors according to a first target range. The processing circuitry determines a set of gradient values associated with a current sample location in a current sub-block from the plurality of sub-blocks according to a reference sub-block. The processing circuitry determines a set of adjustment values associated with the current sample location according to the set of gradient values and an adjustment vector associated with the current sample location. Further, the processing circuitry generates a predicted sample associated with the current sample location according to a combination of a corresponding sample in the reference sub-block and the set of adjustment values.

An apparatus is provided and includes processing circuitry that determines a plurality of first sub-block motion vectors for a plurality of sub-blocks of a current block. The processing circuitry determines a plurality of second sub-block motion vectors by respectively constraining the plurality of first sub-block motion vectors according to a first target range. The processing circuitry determines a set of gradient values associated with a current sample location in a current sub-block from the plurality of sub-blocks according to a reference sub-block. The processing circuitry determines a set of adjustment values associated with the current sample location according to the set of gradient values and an adjustment vector associated with the current sample location. Further, the processing circuitry generates a predicted sample associated with the current sample location according to a combination of a corresponding sample in the reference sub-block and the set of adjustment values.

The present disclosure relates to an image decoding device, an image decoding method, an image encoding device, and an image encoding method that enable further improvement of practicality. Reference image information indicating a reference image to be referred to by a current picture is saved in a header region of an access unit. The reference image information is saved in an AUD NAL unit indicating a delimiter of the access unit or a NEW NAL unit provided separately from the AUD NAL unit, and is applied to all tile group NAL units in the access unit. The present technology can be applied to, for example, an image decoding device and an image encoding device.