15 results about "Variable-length code" patented technology

Wedgelet-based coding for coding blocks of varying size is rendered more efficient by the usage of a variable length coded syntax element having a prefix and a suffix, wherein the size of the suffix is dependent on the prefix and the size of the current coding block. By this measure, it is feasible to efficiently adapt the length of the variable-length coded syntax element which controls the bi-partitioning of the current coding block to the actual needs, namely the size, of the current coding block, and the variability of the bi-partitioning by varying the wedglet separation line, respectively. The greater the current coding block is, the longer the variable-length coded syntax element may be. This length dependency may even be sufficiently effective in terms of coding efficiency so that the variable length coded syntax element may be coded without context-adaptive entropy coding, but directly or using fixed-equal-probability binary entropy coding.

The invention discloses an equipment dynamic variable-length code analysis method. The method comprises the following steps: providing a to-be-analyzed equipment dynamic variable-length code A; establishing a coding feature library T0; retrieving all feature codes in T0 in A to form a simplified sorting code feature library T: retrieving all feature codes in T in A one by one according to sorting, judging whether a character string completely consistent with the currently sorted feature code in T exists in A or not, if yes, extracting the currently sorted feature code in T and the meaning thereof into a decoding set, and if not, extracting the currently sorted feature code in T and the meaning thereof into a decoding set; updating the A, and retrieving the feature codes of the next sequence in the T in the A; otherwise, continuing to retrieve the feature codes of the next sequence in the T in the A; and carrying out integrity analysis on the A through the meaning corresponding to the feature code in the decoding set. The method has the advantages of high analysis efficiency and high analysis accuracy.

The invention belongs to the technical field of communication, and particularly relates to a semantic communication method combining variable length coding and constellation probabilistic shaping, which comprises the following steps of: firstly, constructing a semantic encoder based on a mask auto-encoder framework, and designing a mask rate control function through channel state information and information source characteristics so as to dynamically adjust an information source mask rate; a self-adaptive variable-length coding mechanism is realized; according to the obtained mask rate, sampling a non-masked information source unit by adopting a maximum entropy criterion so as to reserve the information amount of the information source to the maximum extent; the constellation point optimal probability is shaped and approximated to discrete two-dimensional Gaussian distribution, and an end-to-end optimization target is deduced based on variational inference; semantic feature coding distribution is constrained through layer normalization operation to approximate Gaussian prior, so that an objective function is effectively simplified; and finally, designing a quantization modulator of semantic feature-constellation point identical distribution mapping based on finite scalar quantization, and adopting a gradient straight-through estimator to solve the non-differentiable problem of the quantization process, and finally realizing end-to-end joint optimization of the system.

The present invention provides a data compression method and device using a code unit with a predetermined integer constant length, i.e., a constant number of bits, denoted as C, a code unit containing a variable-length code of a syntax element of multiple coding parameters or a fixed-length code of a syntax element of a coding parameter, the length of the compressed data code stream of the coding parameter is always an integer multiple of the length of the code unit, and the encoder or decoder generates or parses the code stream one code unit at a time. In the method and device, both the encoder and the decoder can encode and decode the coding parameters in code units instead of bits, and a plurality of variable-length codes whose sum of lengths is a predetermined integer constant and have a predetermined association with each other are allowed in the code unit, so as to achieve the purpose of taking into account both coding efficiency and computational efficiency.

A data processing system is provided that includes a processing element and a storage device. The storage device stores a code portion that, when executed by the processing element, causes the data processing system to obtain a plurality of variable length codes. Each variable length code has a first portion of variable length and a second portion. The variable length codes are separated into the first portions of the variable length codes and the second portions of the variable length codes. The data processing system uses a set of control rules to form a processed stream in chunks such that for each chunk of the processed stream that contains data from the first portions of the variable length codes, the data from the first portions forms a substream within the chunk of the processed stream having a size determined according to the control rules.

The present invention discloses parallel decoding technology. In various embodiments, a coding sequence including a variable length code (e.g., a compressed sequence for uncompressed data) is decoded in an iterative manner to generate a decoded symbol sequence. During each iteration, a group of threads decodes the code in the coding sequence in parallel to generate a symbol. Then, the thread group calculates an offset based on the size of the symbol. Subsequently, the thread group generates a continuous portion of the decoded sequence in parallel based on the symbol, the output address and the offset.

Wedgelet-based coding for coding blocks of varying size is rendered more efficient by the usage of a variable length coded syntax element having a prefix and a suffix, wherein the size of the suffix is dependent on the prefix and the size of the current coding block. By this measure, it is feasible to efficiently adapt the length of the variable-length coded syntax element which controls the bi-partitioning of the current coding block to the actual needs, namely the size, of the current coding block, and the variability of the bi-partitioning by varying the wedglet separation line, respectively. The greater the current coding block is, the longer the variable-length coded syntax element may be. This length dependency may even be sufficiently effective in terms of coding efficiency so that the variable length coded syntax element may be coded without context-adaptive entropy coding, but directly or using fixed-equal-probability binary entropy coding.

The present disclosure provides systems and methods for communication efficient distributed mean estimation. In particular, aspects of the present disclosure can be implemented by a system in which a number of vectors reside on a number of different clients, and a centralized server device seeks to estimate the mean of such vectors. According to one aspect of the present disclosure, a client computing device can rotate a vector by a random rotation matrix and then subsequently perform probabilistic quantization on the rotated vector. According to another aspect of the present disclosure, subsequent to quantization but prior to transmission, the client computing can encode the quantized vector according to a variable length coding scheme (e.g., by computing variable length codes).

Methods for video decoding and encoding, apparatuses and non-transitory storage media are provided. In one decoding method, the decoder obtains a set of blending strengths for a current block, where the current block is partitioned into two parts along a partition line for prediction in a geometric partitioning mode. Furthermore, the decoder obtains a mapping relationship between a plurality of blending indices and the blending strengths in the set of blending strengths. Moreover, the decoder obtains a binarized value indicating one of the blending indices, where the blending indices are binarized with variable length code. Further, the decoder determines a blending strength of the current block based on the binarized value and the mapping relationship.

In one implementation, we propose to use coset decomposition to improve intra prediction mode coding and decoding. In 67 intra-frame prediction modes, 64 prediction modes are selected for coset decomposition, and the remaining three modes are left in a reduced MPM (most probable mode) list. 64 modes are decomposed into cosets, wherein the number of cosets and the number of modes in the cosets are determined by the size of the target block and / or statistics of intra prediction modes of neighboring blocks. And the intra-frame prediction modes in the cosets are arranged according to a likelihood decreasing sequence. The intra prediction mode of the target block is encoded as a coset index and a member index in the coset. The first coset, namely the first mode in the coset, is encoded with bit 0, and the remaining modes are encoded with fixed or variable length codes.

The invention provides a channel state information feedback method and device based on an adaptive feedback rate. The method comprises the following steps: acquiring a channel state information matrix; inputting the sequence into a pre-training marking encoder based on an attention mechanism, and converting the sequence into a symbol sequence with a fixed length; quantizing the symbol sequence into a discrete index sequence through a pre-training vector quantizer and a codebook; determining a target length according to a real-time channel condition or a dynamically allocated system feedback resource based on a preset importance sorting rule obtained by nesting and discarding training, truncating an index sequence arranged according to an importance descending order, and retaining a front-end index to generate a variable-length feedback code word; and sending the variable-length code word to a base station for reconstruction. According to the method, the dynamic self-adaptive optimization of the feedback rate is realized, the spectrum efficiency is effectively improved, the progressive reconstruction is supported by utilizing the inherent importance sorting of the code words, and the robustness of the system is remarkably enhanced.

A method for decoding image content from an encoded bitstream including a plurality of blocks includes: dividing a block including one or more components of the image content into N single samples and M sample groups corresponding to one of the components, where N and M are greater than or equal to one; decoding each of the N single samples using a symbol variable length code to generate one or more decoded single samples; decoding each of the M sample groups using a common prefix entropy code to generate one or more decoded sample groups, each of the M sample groups including a variable length prefix and one or more fixed length suffixes representing a plurality of samples; concatenating the decoded single samples and the decoded sample groups into a block of residuals; and reconstructing image content based on previously reconstructed neighboring blocks and the block of residuals.

Encoding and / or decoding a block of a video frame may be based on a previously decoded reference block in the same frame or in a different frame. The reference block may be indicated by a block vector (BV). The BV may be encoded as difference (e.g., block vector difference (BVD)) between a block vector predictor (BVP) and the BV. The BVP may indicate a codeword comprising a prefix part and a suffix part. Efficient entropy coding may be achieved by selectively using variable length coding for the prefix part and the suffix part. For example, variable length coding for the prefix part and the suffix part may be used if the prefix part indicates a maximum prefix value.

The present disclosure relates to a method of encoding and decoding image content and a system of transmitting image content, in particular to a method for decoding image content from an encoded bitstream comprising a plurality of blocks, comprising: dividing a block comprising one or more components of the image content into N single samples and M sample groups corresponding to one of the components, wherein N and M are greater than or equal to 1; decoding each of the N single samples using a sign variable length code to generate one or more decoded single samples; decoding each of the M sample groups using a common prefix entropy code to generate one or more decoded sample groups, each of the M sample groups comprising a variable length prefix and one or more fixed length suffixes representing a plurality of samples; concatenating the decoded single samples and the decoded sample groups into a block of residuals; and reconstructing the image content based on previously reconstructed neighboring blocks and the block of residuals.

According to one embodiment, a variable length coding device includes circuitry. The circuitry determines N code lengths corresponding to respective N symbols, based on a Huffman tree. In a case where the N code lengths include a first code length longer than a maximum code length, the circuitry selects a first symbol corresponding to the first code length from the N symbols, selects, from the N symbols, a second symbol corresponding to a second code length shorter than the maximum code length, changes the second code length corresponding to the second symbol to a code length obtained by adding one to the second code length, and changes the first code length corresponding to the first symbol to a code length equal to the changed second code length.