The invention proposes a method and a device for arithmetic encoding of a current spectral coefficient using preceding spectral coefficients. Said preceding spectral coefficients are already encoded and both, said preceding and current spectral coefficients, are comprised in one or more quantized spectra resulting from quantizing time-frequency-transform of video, audio or speech signal sample values.

Said method comprises processing the preceding spectral coefficients, using the processed preceding spectral coefficients for determining a context class being one of at least two different context classes, using the determined context class and a mapping from the at least two different context classes to at least two different probability density functions for determining the probability density function, and arithmetic encoding the current spectral coefficient based on the determined probability density function wherein processing the preceding spectral coefficients comprises non-uniformly quantizing absolutes of the preceding spectral coefficients for use in determining of the context class.

Methods and apparatus are provided for unified significance map coding. An apparatus includes a video encoder (400) for encoding transform coefficients for at least a portion of a picture. The transform coefficients are obtained using a plurality of transforms. One or more context sharing maps are generated for the transform coefficients based on a unified rule. The one or more context sharing maps are for providing at least one context that is shared among at least some of the transform coefficients obtained from at least two different ones of the plurality of transforms.

Methods and apparatus are provided for unified significance map coding. An apparatus includes a video encoder for encoding transform coefficients for at least a portion of a picture. The transform coefficients are obtained using a plurality of transforms. One or more context sharing maps are generated for the transform coefficients based on a unified rule. The one or more context sharing maps are for providing at least one context that is shared among at least some of the transform coefficients obtained from at least two different ones of the plurality of transforms.

Methods and devices for lossy encoding of point clouds. Rate-distortion optimization is used in coding an occupancy pattern for a sub-volume to determine whether to invert any of the bits of the occupancy pattern. The assessment may be a greedy evaluation of whether to invert bits in the coding order. Inverting a bit of the occupancy pattern amounts to adding or removing a point from the point cloud. A distortion metric may measure distance between the point added or removed and its nearest neighbouring point.

An apparatus including a Huffman decoder circuit is described. In a first embodiment, the Huffman decoder circuit includes a register file with simultaneous parallel load capability. The register file is to keep multiple copies of same decoded values in different entries of the register file. The different entries are to be addressed by respective addresses having a same leading edge encoded symbol. The parallel load capability is to simultaneously load a same decoded value for those register file addresses having a same leading edge encoded symbol. In a second embodiment, the Huffman decoder circuit includes a CAM circuit coupled to a register file, wherein respective match lines of the CAM circuit are coupled to respective entries of the register file. The CAM circuit is to keep encoded symbols. The register file is to keep decoded values of the encoded symbols.

A data processing method and device are provided, where the method includes encoding data by using an arithmetic coding algorithm, so as to obtain a code value interval. When a code value corresponding to the data exists in the code value interval, obtaining the code value according to the code value interval. The method further includes comparing a quantity of bits of the code value with a quantity of bits of the data, so as to obtain a comparison result, and performing a storage operation according to the comparison result.

An encoder for encoding data to generate corresponding encoded data including information indicative of a frequency, probability or range of one or more symbols to be represented in the encoded data. The encoder can include in the encoded data additional information indicative of whether information indicative of a frequency, probability or range for at least one symbol amongst the one or more symbols is in the encoded data. The encoder can include in the encoded data the additional information of whether information indicative of a frequency, probability or range for at least one symbol amongst the one or more symbols in the encoded data expressed as single availability bit information. The encoder can represent inclusion of information indicative of the frequency, probability or range information by use of a single availability bit value “7”, and non-inclusion of information indicative of the frequency, probability or range information by use of a single availability bit value “0”.

A method for encoding a series of symbols using several models of the arithmetic or range coder type and including steps where each model is associated with a belonging criterion, the series is run through in order to determine, for each symbol, the encoding model to which each symbol belongs, according to the criteria; then a probability of occurrence of each symbol in the corresponding model is determined; then the series is run through by encoding each symbol successively; and a file is formed from the code thus obtained.

An arithmetic encoder for encoding a plurality of symbols having symbol values is configured to derive an interval size information for an arithmetic encoding of one or more symbol values to be encoded based on a plurality of state variable values representing statistics of a plurality of previously encoded symbol values with different adaptation time constants. The arithmetic encoder is configured to map a first state variable value, or a scaled and/or rounded version thereof, using a lookup-table and to map a second state variable value, or a scaled and/or rounded version thereof using the lookup-table, in order to obtain the interval size information describing an interval size for the arithmetic encoding of one or more symbols to be encoded. Further arithmetic encoders, arithmetic decoders, video encoders, video decoder, methods for encoding, methods for decoding and computer programs are also disclosed which are based on the same concept and on other concepts.

A method for a hardware decompression read pipeline, the method including determining a length and a distance of a first entity from a buffer; launching a first read request for reading a first data from the buffer; obtaining a second entity from the buffer; determining a distance of the second entity; calculating a new distance for the second entity; and decreasing a first counter by one for each cycle that data is read and returned from the buffer, wherein, when a first number of pending read data clock cycles in the first counter is less than a predetermined number of clock cycles and there is no read-after-write conflict: launching a second read request prior to completion of the first read request. In other aspects, a method for a hardware decompression write pipeline and systems for a hardware decompression read pipeline and a hardware decompression write pipeline are provided.