H04N19/197

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.

Methods and apparatus for determining quantization parameter predictors from a plurality of neighboring quantization parameters

Methods and apparatus are provided for determining quantization parameter predictors from a plurality of neighboring quantization parameters. An apparatus includes an encoder for encoding image data for at least a portion of a picture using a quantization parameter predictor for a current quantization parameter to be applied to the image data. The quantization parameter predictor is determined using multiple quantization parameters from previously coded neighboring portions. A difference between the current quantization parameter and the quantization parameter predictor is encoded for signaling to a corresponding decoder.

Using generative adversarial networks in compression

The compression system trains a machine-learned encoder and decoder through an autoencoder architecture. The encoder can be deployed by a sender system to encode content for transmission to a receiver system, and the decoder can be deployed by the receiver system to decode the encoded content and reconstruct the original content. The encoder is coupled to receive content and output a tensor as a compact representation of the content. The content may be, for example, images, videos, or text. The decoder is coupled to receive a tensor representing content and output a reconstructed version of the content. The compression system trains the autoencoder with a discriminator to reduce compression artifacts in the reconstructed content. The discriminator is coupled to receive one or more input content, and output a discrimination prediction that discriminates whether the input content is the original or reconstructed version of the content.

Video encoding method and apparatus, computer-readable storage medium, and computer device

The disclosure relates to a video encoding method and a video encoding apparatus, a computer-readable storage medium, and a computer device. The method includes: acquiring a current video frame and an initial quantization parameter; calculating first historical complexity corresponding to the current video frame at a first time granularity; acquiring a second available bit rate at a second time granularity corresponding to the current video frame and a current first available bit rate at the first time granularity corresponding to the current video frame; adjusting the second available bit rate and the first available bit rate according to complexity of the current video frame and the first historical complexity; updating the initial quantization parameter according to an adjusted second available bit rate to obtain a current quantization parameter; and encoding the current video frame according to the current quantization parameter.

ADJUSTING A SLICE LEVEL QUANTIZATION PARAMETER (QP) BASED ON A MAXIMUM QP VALUE
20230247202 · 2023-08-03 · ·

Aspects of the disclosure provide method and apparatus for video coding. In some examples, an apparatus includes receiving circuitry and processing circuitry. The processing circuitry decodes, from a coded video bitstream, a syntax element for an adjusted version of an initial quantization parameter (QP) value at a picture level for a picture. The adjusted version is in a range with an upper boundary that is changed with a maximum QP value. Then, the processing circuitry determines the initial QP value of a segment (such as a slice, a tile, a group of tiles and the like) in the picture based on the syntax element and determines a QP value for a block in the segment according to the initial QP value of the segment and adjustments associated with the block. Then, the processing circuitry performs an inverse quantization on quantized data of the block according to the determined QP value.

METHOD AND APPARATUS FOR ENCODING/DECODING INTRA PREDICTION MODE

An image decoding method, according to the present invention, includes the steps of: deriving an MPM candidate mode from neighboring blocks adjacent to a target block to be decoded; generating an MPM list using the MPM candidate mode derived from the neighboring blocks; and deriving an intra prediction mode for the target block to be decoded using the generated MPM list. According to the present invention, image compression efficiency can be improved.

VIDEO CODING WITH CONTENT ADAPTIVE SPATIALLY VARYING QUANTIZATION
20220124332 · 2022-04-21 ·

A video encoder may be configured to apply a multi-stage quantization process, where residuals are first quantized using an effective quantization parameter derived from the statistics of the samples of the block. The residual is then further quantized using a base quantization parameter that is uniform across a picture. A video decoder may be configured to decode the video data using the base quantization parameter. The video decoder may further be configured to estimate the effective quantization parameter from the statistics of the decoded samples of the block. The video decoder may then use the estimated effective quantization parameter for use in determining parameters for other coding tools, including filters.

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.

Image decoding method, image coding method, image decoding apparatus, image coding apparatus, and image coding and decoding apparatus

The image decoding method includes determining a context for use in a current block to be processed, from among a plurality of contexts, wherein in the determining: the context is determined under a condition that control parameters of a left block and an upper block are used, when the signal type is a first type; and the context is determined under a third condition that the control parameter of the upper block is not used and a hierarchical depth of a data unit to which the control parameter of the current block belongs is used, when the signal type is a third type, and the third type is one or more of (i) “merge_flag”, (ii) “ref_idx_I0” or “ref_idx_I1”, (iii) “inter_pred_flag”, (iv) “mvd_I0” or “mvd_I1”, (v) “intra_chroma_pred_mode”, (vi) “cbf_luma”, and (vii) “cbf_cb” or “cbf_cr”.

Video coding with content adaptive spatially varying quantization

A video encoder may be configured to apply a multi-stage quantization process, where residuals are first quantized using an effective quantization parameter derived from the statistics of the samples of the block. The residual is then further quantized using a base quantization parameter that is uniform across a picture. A video decoder may be configured to decode the video data using the base quantization parameter. The video decoder may further be configured to estimate the effective quantization parameter from the statistics of the decoded samples of the block. The video decoder may then use the estimated effective quantization parameter for use in determining parameters for other coding tools, including filters.