Dynamic motion vector referencing is used to predict motion within video blocks. A motion trajectory is determined for a current frame including a video block to encode or decode based on a reference motion vector used for encoding or decoding one or more reference frames of the current frame. One or more temporal motion vector candidates are then determined for predicting motion within the video block based on the motion trajectory. A motion vector is selected from a motion vector candidate list including the one or more temporal motion vector candidates and used to generate a prediction block. The prediction block is then used to encode or decode the video block. The motion trajectory is based on an order of video frames indicated by frame offset values encoded to a bitstream. The motion vector candidate list may include one or more spatial motion vector candidates.

Dynamic motion vector referencing is used to predict motion within video blocks. A motion trajectory is determined for a current frame including a video block to encode or decode based on a reference motion vector used for encoding or decoding one or more reference frames of the current frame. One or more temporal motion vector candidates are then determined for predicting motion within the video block based on the motion trajectory. A motion vector is selected from a motion vector candidate list including the one or more temporal motion vector candidates and used to generate a prediction block. The prediction block is then used to encode or decode the video block. The motion trajectory is based on an order of video frames indicated by frame offset values encoded to a bitstream. The motion vector candidate list may include one or more spatial motion vector candidates.

The present invention is about an image encoding/decoding method and apparatus. According to present invention, a method of decoding an image, the method comprising, deriving an initial motion vector of a current block; deriving a refined motion vector by using the initial motion vector; and generating a prediction block of the current block by using the refined motion vector.

Hybrid video decoder supporting intermediate view synthesis of an intermediate view video from a first- and a second-view video which are predictively coded into a multi-view data signal with frames of the second-view video being spatially subdivided into sub-regions and the multi-view data signal having a prediction mode is provided, having: an extractor configured to respectively extract, from the multi-view data signal, for sub-regions of the frames of the second-view video, a disparity vector and a prediction residual; a predictive reconstructor configured to reconstruct the sub-regions of the frames of the second-view video, by generating a prediction from a reconstructed version of a portion of frames of the first-view video using the disparity vectors and a prediction residual for the respective sub-regions; and an intermediate view synthesizer configured to reconstruct first portions of the intermediate view video.

Hybrid video decoder supporting intermediate view synthesis of an intermediate view video from a first- and a second-view video which are predictively coded into a multi-view data signal with frames of the second-view video being spatially subdivided into sub-regions and the multi-view data signal having a prediction mode is provided, having: an extractor configured to respectively extract, from the multi-view data signal, for sub-regions of the frames of the second-view video, a disparity vector and a prediction residual; a predictive reconstructor configured to reconstruct the sub-regions of the frames of the second-view video, by generating a prediction from a reconstructed version of a portion of frames of the first-view video using the disparity vectors and a prediction residual for the respective sub-regions; and an intermediate view synthesizer configured to reconstruct first portions of the intermediate view video.

According to an embodiment, an image coding method is for coding an image including a luminance component and color difference components. The method includes acquiring a reference image; and generating a predicted image by interpolating the luminance component and the color difference components in the reference image according to a motion vector. If a size of a block, which is designated as a unit of the interpolation, is equal to or smaller than a predetermined first threshold value, the generating includes inhibiting a bi-directional prediction, and performing only a uni-directional prediction to generate the predicted image according to the motion vector.

A method of decoding video data may comprise decoding data from an encoded bitstream to generate motion vectors and performing a decoder-side motion vector refinement (DMVR) process on one or more of the motion vectors. Performing the DMVR process may include determining one or more characteristics of current video block being decoded and determining a search area for the DMVR process for the current video block based on the determined one or more characteristics of the current video block.

Encoding frames of a video stream may include encoding a current block of a current frame, generating a base prediction block for the current block based on current prediction parameters associated with the current block, identifying adjacent prediction parameters used for encoding previously encoded adjacent blocks that are adjacent to the current block. At least one side of the current block is adjacent to two or more of the previously encoded adjacent blocks. The encoding may include determining overlap regions in the current block, each of the overlap regions corresponding to a respective previously encoded adjacent block, generating an overlapped prediction of pixel values for each of the overlap regions according to a weighted function of the base prediction and a prediction based on the adjacent prediction parameters. The weighted function may be based on a difference between the current prediction parameters and the adjacent prediction parameters.

Encoding frames of a video stream may include encoding a current block of a current frame, generating a base prediction block for the current block based on current prediction parameters associated with the current block, identifying adjacent prediction parameters used for encoding previously encoded adjacent blocks that are adjacent to the current block. At least one side of the current block is adjacent to two or more of the previously encoded adjacent blocks. The encoding may include determining overlap regions in the current block, each of the overlap regions corresponding to a respective previously encoded adjacent block, generating an overlapped prediction of pixel values for each of the overlap regions according to a weighted function of the base prediction and a prediction based on the adjacent prediction parameters. The weighted function may be based on a difference between the current prediction parameters and the adjacent prediction parameters.

A moving picture coding apparatus includes an intra-inter prediction unit which calculates a second motion vector by performing a scaling process on a first motion vector of a temporally neighboring corresponding block, when selectively adding, to a list, a motion vector of each of one or more corresponding blocks each of which is either a block included in a current picture to be coded and spatially neighboring a current block to be coded or a block included in a picture other than the current picture and temporally neighboring the current block, determines whether the second motion vector has a magnitude that is within a predetermined magnitude or not within the predetermined magnitude, and adds the second motion vector to the list when the intra-inter prediction unit determines that the second motion vector has a magnitude that is within the predetermined magnitude range.