Patent classifications
H04N19/647
Block-Based Predictive Coding For Point Cloud Compression
An encoder is configured to compress point cloud information using a blocks of nodes determined from a prediction tree. A prediction tree is generated for a point cloud. Segments of the prediction tree are identified. The segments are divided into blocks that are predicted by predecessor blocks within the segments. The blocks of the prediction tree may then be encoded and may be provided for transmission to a decoder that can regenerate the point cloud from the blocks of the prediction tree.
Intra block copy for video coding
This disclosure describes example techniques that a video coder (e.g., video encoder or video decoder) may utilize to determine a block vector for a chroma block where the partition trees for the chroma component and the luma component are different (e.g., decoupled partition trees).
METHOD OF CODING TRANSFORM COEFFICIENT BASED ON HIGH FREQUENCY ZEROING AND APPARATUS THEREOF
An image decoding method performed by a decoding apparatus according to the present disclosure includes receiving a bitstream including residual information; deriving quantized transform coefficients for a current block based on the residual information included in the bitstream; deriving residual samples for the current block based on the quantized transform coefficients; and generating a reconstructed picture based on the residual samples for the current block.
Adaptive subblock size for affine motion compensation
A video encoder and/or video decoder may determine the size of subblocks of a block of video data, where the block of video data is to be encoded or decoded using subblock affine motion compensation mode. The video encoder and/or video decoder may receive a block of video data to be coded using a subblock affine motion compensation mode, determine a size of one or more subblocks of the block based on one or more of an inter prediction direction or affine motion parameters of the block, partition the block into the one or more subblocks based on the determined size, and code the one or more subblocks using the subblock affine motion compensation mode.
Systems and methods for signaling picture order count values for pictures included in coded video
A video device to determine picture count information for decoding video pictures is provided. The video device decodes a picture order count (POC) most significant bit (MSB) first flag that indicates whether a POC MSB second flag is present. When the POC MSB second flag is present, the video device decodes the POC MSB second flag indicating whether a POC MSB cycle element is present. When the POC MSB cycle element is present, the video device decodes the POC MSB cycle element that specifies a value of a POC MSB cycle. The value of the POC MSB cycle is used to compute a POC MSB value that is combined with a POC least significant bit (LSB) value to produce a POC value used for decoding a first video picture, and a length of the POC LSB value is based on a maximum POC LSB minus four value.
Method and apparatus for fast and efficient image compression and decompression
The invention relates to a method and apparatus for fast and efficient image compression and decompression comprising transform coding of image data to generate an image representation using transform coefficients, bit-plane serialization of the image representation using transform coefficients, and for each bitplane optimal prefix encoding of bits in a bitplane sharing local context, run-length encoding of 0 bit sequences in the bitplane and storing the coefficients received after optimal prefix encoding and 0 run length encoding starting with the sign followed by the bits in the order of significance, starting with the most significant bit to the least significant bit in a seektable in a header section.
Apparatus and method for encoding or decoding using a subband dependent prediction adaptation for GCLI entropy coding
An apparatus for encoding image data, the image data being decomposed into a plurality of different subbands, each subband having a plurality of coefficients, wherein a precinct has different sets of coefficients from different subbands, wherein two sets of coefficients of a first precinct belong to a first spatial region of an image represented by the image data, the apparatus having: a processor for determining, for each group of coefficients within a set, a greatest coded line index (GCLI); an encoder for encoding the greatest coded line indices associated with a first set of the first precinct in accordance with a first encoding mode, and for encoding the greatest coded line indices associated with a second set of the first precinct in accordance with a second encoding mode, the second encoding mode being different from the first encoding mode; and an output interface for outputting an encoded image signal having data on the encoded greatest coded line indices and data on the coefficients.
Template matching for JVET intra prediction
A method of decoding JVET video, comprising defining a coding unit (CU) template within a decoded area of a video frame, the CU template being positioned above and/or to the left of a current decoding position for which data was intra predicted, defining a search window within the decoded area, the search window being adjacent to the CU template, generating a plurality of candidate prediction templates based on pixel values in the search window, each of the plurality of candidate prediction templates being generated using different intra prediction modes, calculating a matching cost between the CU template and each of the plurality of candidate prediction templates, selecting an intra prediction mode that generated the candidate prediction template that had the lowest matching cost relative to the CU template, and generating a prediction CU for the current decoding position based on the intra prediction mode.
Method and apparatus for image compression
The invention relates to a method and apparatus for image compression, particularly to an improved block-coding apparatus and method for image compression. Image compression systems such as JPEG and JPEG2000 are known and popular standards for image compression. Many of the advantageous features of JPEG2000 derive from the use of the EBCOT algorithm (Embedded Block-Coding with Optimized Truncation). One drawback of the JPEG2000 standards is computational complexity. This application discloses a relatively fast block-coding algorithm, particularly as compared with the standard JPEG2000 EBCOT algorithm. Computational complexity is reduced.
WEIGHTED ANGULAR PREDICTION FOR INTRA CODING
A method of decoding JVET video, comprising receiving a bitstream indicating how a coding tree unit was partitioned into coding units according to a partitioning structure that allows nodes to be split according to a partitioning technique. An intra direction mode for a coding unit may be selected, as well as one or more of the plurality of reference lines to generate at least one predictor for the intra direction mode. A predictor may be generated from reference samples within each selected reference line by combining predicted pixel values based on a projected position on a main reference line in combination with predicted pixel values based on a projected position on a side reference line. The predicted pixel values are weighted according to a weight parameter, wherein the weight parameter is determined based on a shift conversion factor.