A video encoding apparatus includes a content activity analyzer circuit and a video encoder circuit. The content activity analyzer circuit applies a content activity analysis process to consecutive frames, to generate content activity analysis results. The consecutive frames are derived from input frames of the video encoding apparatus. The content activity analysis process includes: deriving a first content activity analysis result according to a first frame and a second frame in the consecutive frames, wherein the first content activity analysis result includes a processed frame distinct from the second frame; and deriving a second content activity analysis result according to a third frame included in the consecutive frames and the processed frame. The video encoder circuit performs a video encoding process to generate a bitstream output of the video encoding apparatus, wherein information derived from the content activity analysis results is referenced by the video encoding process.

Systems and methods for reducing latency through motion estimation and compensation techniques are disclosed. The systems and methods include a client device that uses transmitted lookup tables from a remote server to match user input to motion vectors, and tag and sum those motion vectors. When a remote server transmits encoded video frames to the client, the client decodes those video frames and applies the summed motion vectors to the decoded frames to estimate motion in those frames. In certain embodiments, the systems and methods generate motion vectors at a server based on predetermined criteria and transmit the generated motion vectors and one or more invalidators to a client, which caches those motion vectors and invalidators. The server instructs the client to receive input from a user, and use that input to match to cached motion vectors or invalidators. Based on that comparison, the client then applies the matched motion vectors or invalidators to effect motion compensation in a graphic interface. In other embodiments, the systems and methods cache repetitive motion vectors at a server, which transmits a previously generated motion vector library to a client. The client stores the motion vector library, and monitors for user input data. The server instructs the client to calculate a motion estimate from the input data and instructs the client to update the stored motion vector library based on the input data, so that the client applies the stored motion vector library to initiate motion in a graphic interface prior to receiving actual motion vector data from the server. In this manner, latency in video data streams is reduced.

Systems and methods for reducing latency through motion estimation and compensation techniques are disclosed. The systems and methods include a client device that uses transmitted lookup tables from a remote server to match user input to motion vectors, and tag and sum those motion vectors. When a remote server transmits encoded video frames to the client, the client decodes those video frames and applies the summed motion vectors to the decoded frames to estimate motion in those frames. In certain embodiments, the systems and methods generate motion vectors at a server based on predetermined criteria and transmit the generated motion vectors and one or more invalidators to a client, which caches those motion vectors and invalidators. The server instructs the client to receive input from a user, and use that input to match to cached motion vectors or invalidators. Based on that comparison, the client then applies the matched motion vectors or invalidators to effect motion compensation in a graphic interface. In other embodiments, the systems and methods cache repetitive motion vectors at a server, which transmits a previously generated motion vector library to a client. The client stores the motion vector library, and monitors for user input data. The server instructs the client to calculate a motion estimate from the input data and instructs the client to update the stored motion vector library based on the input data, so that the client applies the stored motion vector library to initiate motion in a graphic interface prior to receiving actual motion vector data from the server. In this manner, latency in video data streams is reduced.

A picture decoding method performed by a decoding apparatus according to the present disclosure includes obtaining motion prediction information from bitstream, generating an affine MVP candidate list including affine MVP candidates for a current block, deriving CPMVPs for respective CPs of the current block based on one of the affine MVP candidates included in the affine MVP candidate list, deriving the CPMVDs for the CPs of the current block based on information on CPMVDs for each of the CPs included in the obtained motion prediction information, deriving CPMVs for the CPs of the current block based on the CPMVPs and the CPMVDs, deriving prediction samples for the current block based on the CPMVs, and generating reconstructed samples for the current block based on the derived prediction samples.

A picture decoding method performed by a decoding apparatus according to the present disclosure includes obtaining motion prediction information from bitstream, generating an affine MVP candidate list including affine MVP candidates for a current block, deriving CPMVPs for respective CPs of the current block based on one of the affine MVP candidates included in the affine MVP candidate list, deriving the CPMVDs for the CPs of the current block based on information on CPMVDs for each of the CPs included in the obtained motion prediction information, deriving CPMVs for the CPs of the current block based on the CPMVPs and the CPMVDs, deriving prediction samples for the current block based on the CPMVs, and generating reconstructed samples for the current block based on the derived prediction samples.

Method, apparatus and systems are disclosed. In one embodiment, a method of decoding includes obtaining a sub-block based motion prediction signal for a current block of the video; obtaining one or more spatial gradients of the sub-block based motion prediction signal or one or more motion vector difference values; obtaining a refinement signal for the current block based on the one or more obtained spatial gradients or the one or more obtained motion vector difference values; obtaining a refined motion prediction signal for the current block based on the sub-block based motion prediction signal and the refinement signal; and decoding the current block based on the refined motion prediction signal.

Method, apparatus and systems are disclosed. In one embodiment, a method of decoding includes obtaining a sub-block based motion prediction signal for a current block of the video; obtaining one or more spatial gradients of the sub-block based motion prediction signal or one or more motion vector difference values; obtaining a refinement signal for the current block based on the one or more obtained spatial gradients or the one or more obtained motion vector difference values; obtaining a refined motion prediction signal for the current block based on the sub-block based motion prediction signal and the refinement signal; and decoding the current block based on the refined motion prediction signal.

An image decoding method is disclosed in the present specification. An image decoding method according to the present invention may comprise determining a prediction mode of a current block and performing prediction with respect to the current block on the basis of the determined prediction mode.

An image decoding method is disclosed in the present specification. An image decoding method according to the present invention may comprise determining a prediction mode of a current block and performing prediction with respect to the current block on the basis of the determined prediction mode.

A video encoding method includes (i) determining a current bit rate of a communication channel between a destination device and a source device that stores an input video frame, and (ii) generating a current reconstructed frame and an encoded bitstream at least in part via inter-frame coding of a current input video frame of a sequence of input video frames using a previously-generated reconstructed frame generated at least in part via inter-frame coding of a previous input video frame. The current reconstructed frame is a compressed version of the current input video frame. When both (i) a subsequent bit rate, determined after said inter-frame coding, is less than a threshold and (ii) the current bit rate exceeds the threshold, the method includes: (a) generating a downscaled reconstructed frame at least in part by downscaling the current reconstructed frame; and (b) appending the encoded bitstream with a bit sequence representing the downscaled reconstructed frame.