The present invention relates to a scalable video coding method and apparatus using inter prediction mode. A decoding method includes determining motion information prediction mode on a target decoding block of an enhancement layer, predicting motion information on the target decoding block of the enhancement layer using motion information on the neighboring blocks of the enhancement layer, if the determined motion information prediction mode is a first mode, and predicting the motion information on the target decoding block of the enhancement layer using motion information on a corresponding block of a reference layer, if the determined motion information prediction mode is a second mode.

Provided is a video decoding method including: obtaining, from a bitstream, prediction motion vector information indicating a prediction motion vector of a current block and difference motion vector information indicating a difference motion vector of the current block; determining the prediction motion vector of the current block according to whether or not an adjacent block of the current block is decoded and the prediction motion vector information; determining a motion vector resolution of the current block according to whether or not the adjacent block of the current block is decoded; determining the difference motion vector of the current block according to the difference motion vector information; determining a motion vector of the current block according to the prediction motion vector, the motion vector resolution, and the difference motion vector; and reconstructing the current block according to the motion vector of the current block, wherein the adjacent block of the current block includes a right block of the current block.

Provided is a video decoding method including: obtaining, from a bitstream, prediction motion vector information indicating a prediction motion vector of a current block and difference motion vector information indicating a difference motion vector of the current block; determining the prediction motion vector of the current block according to whether or not an adjacent block of the current block is decoded and the prediction motion vector information; determining a motion vector resolution of the current block according to whether or not the adjacent block of the current block is decoded; determining the difference motion vector of the current block according to the difference motion vector information; determining a motion vector of the current block according to the prediction motion vector, the motion vector resolution, and the difference motion vector; and reconstructing the current block according to the motion vector of the current block, wherein the adjacent block of the current block includes a right block of the current block.

A method (20) is disclosed performed in an encoder (40) for encoding video pictures into a video bit stream, the method (20) comprising: obtaining (21) a transformed version (2′; 12′, 13′) of a reference picture (2; 12, 13), by using a geometric transformation comprising at least one of: scaling, rotation, shearing, reflection, and projection; performing (22) a matching procedure at least once, the matching procedure comprising matching a reference matching area (6; 15, 16) of the reference picture (2; 12, 13) to a matching area (4; 16, 15) of a second picture (1; 13, 12) and matching a reference matching area (6′; 15′, 16′) of the transformed version (2′; 12′, 13′) to the matching area (4; 16, 15) of the second picture (1; 13, 12); and encoding (23) a block (3; 14) of the current picture (1; 11) by selecting for the block (3; 14) a first prediction area (5; 15, 16) based on the reference matching area (6; 15, 16) or a second prediction area (5′; 15′, 16′) based on the transformed reference matching area (6′; 15′, 16′), wherein the first and second prediction areas at least partly overlap the respective reference matching areas (6; 6′; 15, 16, 15′, 16′) and wherein the prediction area having lowest matching error to a corresponding matching area (4; 15, 16) of the second picture (1; 13, 12) is selected as prediction for the block. A corresponding method (30) in a decoder (50) is disclosed, and encoder (40), decoder (50), computer programs and computer program products.

An image decoding method performed by a decoding device according to the present document comprises the steps of: deriving a temporary reference motion vector regarding a current block on the basis of a temporal periphery block included in a reference picture of a current picture including the current block; deriving a binary code indicating a reference motion vector by applying a shifting operation to a binary code indicating the temporary reference motion vector; storing information regarding the binary code indicating the reference motion vector; deriving a motion vector regarding the current block on the basis of the reference motion vector; deriving a predicted block regarding the current block on the basis of the motion vector regarding the current block; and generating a restored picture regarding the current picture on the basis of the predicted block regarding the current block.

A prefetched-image memory stores a prefetched image of a prefetched area prefetched from a reference image memory that stores a reference image. A processor performs a motion search using a reduced image obtained by reducing an encoding target image and generates a search result for an encoding target block included in the encoding target image. The processor determines, based on the search result, that an area situated outside the prefetched area in the reference image is to be searched when the processor has predicted from the search result that a matching of the encoding target block and the prefetched image will be unsuccessful. Next, the processor performs a matching of the encoding target block and an image of a matching target area including the outside area in the reference image and generates an inter-prediction result. Then, the processor encodes the encoding target block based on the inter-prediction result.

The disclosed invention is a enhancement to the Video Encoder component of the MPEG standard to improve both the efficiency and quality of the video presentation at the display device. The inventions described below pertain to the enhancement of video compression technology. In general, they are compatible with MPEG video standards (as in current art), but represent novel enhancements thereof. The above inventions apply to several transmission media and networks including cable, DSL, wireless, satellite and IP networks. Another category of invention in this disclosure enhances networking performance by recognizing that the transmitted information is video, rather than data. This invention can be scaled to other classes of multimedia data such as speech or audio or images.

The disclosed invention is a enhancement to the Video Encoder component of the MPEG standard to improve both the efficiency and quality of the video presentation at the display device. The inventions described below pertain to the enhancement of video compression technology. In general, they are compatible with MPEG video standards (as in current art), but represent novel enhancements thereof. The above inventions apply to several transmission media and networks including cable, DSL, wireless, satellite and IP networks. Another category of invention in this disclosure enhances networking performance by recognizing that the transmitted information is video, rather than data. This invention can be scaled to other classes of multimedia data such as speech or audio or images.

Disclosed is a low-complexity and yet efficient lossy method to compress distortion information for motion estimation, resulting in significant reduction in needed storage capacity. A system for implementing the method and a computer-readable medium for storing the method are also disclosed. The method includes determining and storing a distortion value for each trial motion vector in a plurality of trial motion vectors. Each trial motion vector specifies a position of a search region relative to a reference frame. The method further includes compressing each of the distortion values as a fixed number of bits based upon a minimum distortion value amongst the stored distortion values, and re-storing each compressed distortion value in place of its uncompressed value.

Techniques related to video coding with a multi-pass prediction mode decision pipeline.