A device includes one or more processors configured to execute instructions to obtain motion data indicating estimated motion between a first frame and a second frame of an input sequence of image frames, and to identify, based on the motion data, any frame regions of the first frame that indicate motion greater than a motion threshold. The one or more processors are also configured to determine, based on the motion data, a motion metric associated with the identified frame regions, and to perform a determination, based on the motion metric and a size metric associated with the identified frame regions, whether to use motion-compensated frame interpolation to generate an intermediate frame. The one or more processors are further configured to generate the intermediate frame based on the determination, and to generate an output sequence of image frames that includes the intermediate frame between the first frame and the second frame.

A device includes one or more processors configured to execute instructions to obtain motion data indicating estimated motion between a first frame and a second frame of an input sequence of image frames, and to identify, based on the motion data, any frame regions of the first frame that indicate motion greater than a motion threshold. The one or more processors are also configured to determine, based on the motion data, a motion metric associated with the identified frame regions, and to perform a determination, based on the motion metric and a size metric associated with the identified frame regions, whether to use motion-compensated frame interpolation to generate an intermediate frame. The one or more processors are further configured to generate the intermediate frame based on the determination, and to generate an output sequence of image frames that includes the intermediate frame between the first frame and the second frame.

An encoder includes circuitry and a memory coupled to the circuitry, wherein the circuitry, in operation, performs a partition process. The partition process includes calculating first values of a set of pixels between a first partition and a second partition in a current block, using a first motion vector for the first partition; calculating second values of the set of pixels, using a second motion vector for the second partition; and calculating third values of the set of pixels by weighting the first values and the second values. When a ratio of a width to a height of the current block is larger than 4 or a ratio of the height to the width of the current block is larger than 4, the circuitry disables the partition process.

Metadata and methods for variable-frame rate (VFR) video playback are presented. Proposed metadata include syntax parameters related to the presentation time duration, picture source type (e.g., original, duplicate, or interpolated), picture position in a scene (e.g., first, last, or in the middle), and motion-related information with respect to a previous picture. A decoder may use these metadata to apply appropriate frame-rate conversion techniques to reduce artifacts during VFR playback.

Innovations in adaptive encoding for units of a video sequence can improve coding efficiency. For example, some of the innovations relate to encoding that includes adaptive switching of color spaces between units within a video sequence. Other innovations relate encoding that includes adaptive switching of color sampling rates between units within a video sequence. Still other innovations relate encoding that includes adaptive switching of bit depths between units within a video sequence.

Innovations in adaptive encoding for units of a video sequence can improve coding efficiency. For example, some of the innovations relate to encoding that includes adaptive switching of color spaces between units within a video sequence. Other innovations relate encoding that includes adaptive switching of color sampling rates between units within a video sequence. Still other innovations relate encoding that includes adaptive switching of bit depths between units within a video sequence.

In the present disclosure, a method of decoding a video signal and a device therefor are disclosed. Specifically, a method of decoding an image based on an inter prediction mode includes deriving a motion vector of an available spatial neighboring block around a current block; deriving a collocated block of the current block based on the motion vector of the spatial neighboring block; deriving a motion vector in a sub-block unit in the current block based on a motion vector of the collocated block; and generating a prediction block of the current block using the motion vector derived in the sub-block unit, wherein the collocated block may be specified by the motion vector of the spatial neighboring block in one pre-defined reference picture.

In the present disclosure, a method of decoding a video signal and a device therefor are disclosed. Specifically, a method of decoding an image based on an inter prediction mode includes deriving a motion vector of an available spatial neighboring block around a current block; deriving a collocated block of the current block based on the motion vector of the spatial neighboring block; deriving a motion vector in a sub-block unit in the current block based on a motion vector of the collocated block; and generating a prediction block of the current block using the motion vector derived in the sub-block unit, wherein the collocated block may be specified by the motion vector of the spatial neighboring block in one pre-defined reference picture.

Innovations in video decoding and rendering operations for inter-coded blocks in a graphics pipeline, in which at least some of the operations are performed using a graphics processing unit (“GPU”), are described. For example, a video playback tool receives encoded data for a current picture and performs operations to decode the encoded data and reconstruct the current picture. For a given inter-coded block of the current picture, a graphics primitive represents texture values as a point for processing by the GPU. The graphics primitive can have one or more attributes, including a motion vector, a block size, a display index value (indicating a location in a display buffer), and/or a residual index value (indicating a location of residual values). The operations performed by the video playback tool can include interpolation of sample values at fractional-sample offsets and motion compensation performed for inter-coded blocks in multiple passes for different block sizes.

Innovations in video decoding and rendering operations for inter-coded blocks in a graphics pipeline, in which at least some of the operations are performed using a graphics processing unit (“GPU”), are described. For example, a video playback tool receives encoded data for a current picture and performs operations to decode the encoded data and reconstruct the current picture. For a given inter-coded block of the current picture, a graphics primitive represents texture values as a point for processing by the GPU. The graphics primitive can have one or more attributes, including a motion vector, a block size, a display index value (indicating a location in a display buffer), and/or a residual index value (indicating a location of residual values). The operations performed by the video playback tool can include interpolation of sample values at fractional-sample offsets and motion compensation performed for inter-coded blocks in multiple passes for different block sizes.