A motion vector coding unit executes processing including a neighboring block specification step of specifying a neighboring block which is located in the neighborhood of a current block; a judgment step of judging whether or not the neighboring block has been coded using a motion vector of another block; a prediction step of deriving a predictive motion vector of the current block using a motion vector calculated from the motion vector of the other block as a motion vector of the neighboring block; and a coding step of coding the motion vector of the current block using the predictive motion vector.

A motion vector coding unit executes processing including a neighboring block specification step of specifying a neighboring block which is located in the neighborhood of a current block; a judgment step of judging whether or not the neighboring block has been coded using a motion vector of another block; a prediction step of deriving a predictive motion vector of the current block using a motion vector calculated from the motion vector of the other block as a motion vector of the neighboring block; and a coding step of coding the motion vector of the current block using the predictive motion vector.

A picture encoding/decoding method and a related apparatus are provided. The picture decoding method includes obtaining a current picture; selecting, from a knowledge base, K reference pictures of the current picture, where at least one picture in the knowledge base does not belong to a random access segment in which the current picture is located and wherein K is an integer greater than or equal to 1; and decoding the current picture according to the K reference pictures.

Syntax structures that indicate the completion of coded regions of pictures are described. For example, a syntax structure in an elementary bitstream indicates the completion of a coded region of a picture. The syntax structure can be a type of network abstraction layer unit, a type of supplemental enhancement information message or another syntax structure. For example, a media processing tool such as an encoder can detect completion of a coded region of a picture, then output, in a predefined order in an elementary bitstream, syntax structure(s) that contain the coded region as well as a different syntax structure that indicates the completion of the coded region. Another media processing tool such as a decoder can receive, in a predefined order in an elementary bitstream, syntax structure(s) that contain a coded region of a picture as well as a different syntax structure that indicates the completion of the coded region.

Syntax structures that indicate the completion of coded regions of pictures are described. For example, a syntax structure in an elementary bitstream indicates the completion of a coded region of a picture. The syntax structure can be a type of network abstraction layer unit, a type of supplemental enhancement information message or another syntax structure. For example, a media processing tool such as an encoder can detect completion of a coded region of a picture, then output, in a predefined order in an elementary bitstream, syntax structure(s) that contain the coded region as well as a different syntax structure that indicates the completion of the coded region. Another media processing tool such as a decoder can receive, in a predefined order in an elementary bitstream, syntax structure(s) that contain a coded region of a picture as well as a different syntax structure that indicates the completion of the coded region.

Various innovations in media encoding are presented herein. In particular, the innovations can reduce the computational complexity of encoding by selectively skipping certain evaluation stages during encoding. For example, based on analysis of decisions made earlier in encoding or based on analysis of media to be encoded, an encoder can selectively skip evaluation of certain coding tools (such as residual coding or rate-distortion-optimized quantization), skip evaluation of certain values for parameters or settings (such as candidate unit sizes or transform sizes, or candidate partition patterns for motion compensation), and/or skip evaluation of certain coding modes (such as frequency transform skip mode) that are not expected to improve rate-distortion performance during encoding.

A compression device for compressing image data generated by a computed tomography (CT) imaging system is described herein. The compression device is configured to compress the image data by implementing a method including receiving image data from the CT imaging system and requantizing the image data in a square root domain. The method further includes identifying a group of projections (GOP) in the image data, including a first projection and a plurality of subsequent projections, and performing spatial-delta encoding on the first projection and temporal-delta encoding on each of the plurality of subsequent projections. The method also includes identifying a signed value in the GOP, and converting the signed value to an unsigned value. The method further includes entropy coding the image data in the GOP, and packetizing the GOP for transmission or storage.

A compression device for compressing image data generated by a computed tomography (CT) imaging system is described herein. The compression device is configured to compress the image data by implementing a method including receiving image data from the CT imaging system and requantizing the image data in a square root domain. The method further includes identifying a group of projections (GOP) in the image data, including a first projection and a plurality of subsequent projections, and performing spatial-delta encoding on the first projection and temporal-delta encoding on each of the plurality of subsequent projections. The method also includes identifying a signed value in the GOP, and converting the signed value to an unsigned value. The method further includes entropy coding the image data in the GOP, and packetizing the GOP for transmission or storage.

Methods (1100, 1300) and apparatuses (600, 1200) for video coding and decoding are provided. The method of video encoding includes accessing (1110) a reconstructed block corresponding to a block in a picture of a video, determining (1120) at least one filter pattern based on a property of the block and filtering (1130) the reconstructed block according to the at least one filter pattern. The method of video decoding includes accessing (1310) a reconstructed block corresponding to a block in a picture of an encoded video, determining (1320) at least one filter pattern based on a property of the block and filtering (1330) the reconstructed block according to the at least one filter pattern. A bitstream formatted to include encoded data, a computer-readable storage medium and a computer program product are also described.

Video processing methods and apparatuses include receiving input video data associated with a current picture composed of multiple Coding Tree Units (CTUs) for encoding or decoding, determining a number of subpictures, partitioning the current picture into one or more subpictures, and encoding or decoding each subpicture in the current picture. Each subpicture contains multiple complete CTUs and boundaries of each subpicture are aligned with grids of the current picture in units of CTUs. The number of subpictures in the current picture is limited by an allowed maximum number of slices.