Abstract: A method is providing for encoding at least one image cut into blocks. The method implements, for a current block to be encoded, acts of: predicting the current block in accordance with a prediction mode selected among predetermined prediction modes; obtaining a predictor block; determining a residual data set, representative of the difference between the predictor block obtained and the current block, the residual data being likely to have an amplitude and a sign; selecting, from the residual data set, a piece of residual data assigned an amplitude and a sign, using a predetermined criterion which is a function of the selected prediction mode; obtaining a predicted value of the sign of the selected piece of residual data; calculating information representing the difference between the predicted value of the sign and the value of the sign of the selected piece of residual data; and encoding the calculated information.

Abstract: A method of coding at least one image comprising the steps of splitting the image into a plurality of blocks, of grouping said blocks into a predetermined number of subsets of blocks, of coding each of said subsets of blocks in parallel, the blocks of a subset considered being coded according to a predetermined sequential order of traversal. The coding step comprises, for a current block of a subset considered, the sub-step of predictive coding of said current block with respect to at least one previously coded and decoded block, and the sub-step of entropy coding of said current block on the basis of at least one probability of appearance of a symbol.

Abstract: A method is provided for coding at least one image split up into partitions, a current partition to be coded containing data, at least one data item of which is allotted a sign. The coding method includes, for the current partition, the following steps: calculating the value of a function representative of the data of the current partition with the exclusion of the sign; comparing the calculated value with a predetermined value of the sign; as a function of the result of the comparison, modifying or not modifying at least one of the data items of the current partition, in the case of modification, coding the at least one modified data item.

Abstract: A method for coding includes; segmenting an image into blocks; grouping blocks into a number of subsets; coding, using an entropy coding module, each subset, by associating digital information with symbols of each block of a subset, including, for the first block of the image, initializing state variables of the coding module; and generating a data sub-stream representative of at least one of the coded subsets of blocks. Where a current block is the first block to be coded of a subset, symbol occurrence probabilities for the first current block are determined based on those for a coded and decoded predetermined block of at least one other subset. Where the current block is the last coded block of the subset: writing, in the sub-stream representative of the subset, the entire the digital information associated with the symbols during coding of the blocks of the subset, and implementing the initializing sub-step.

Abstract: A method of decoding an encoded data stream representing at least one image subdivided into blocks. The method includes, for a current block of the image, and for each of at least two prediction modes available to predict the current block, obtaining a predictive block associated with the available mode; building a list having at least one of the available modes; for at least one mode included in the list, called a current mode, determining a distance measurement between the predictive block associated with the current mode and the other predictive blocks associated with the other available modes and obtained for the current block; modifying the list modified as a function of the determined measurement; decoding information identifying, for the current block, a prediction mode from the modified list from the encoded data stream; and rebuilding the current block from the predictive block associated with the identified prediction mode.

Abstract: A method for decoding a coded data stream representative of at least one image, the image being divided into blocks, a set of at least two prediction modes being available for predicting a current block. The method includes: obtaining at least two categories of prediction modes from the set; eliminating at least one category in accordance with at least one first predetermined elimination criterion; updating the categories not eliminated by deleting prediction modes that are common with the at least one eliminated category; and decoding, from the data stream, an information identifying for the current block a prediction mode among the modes of the updated categories.

Abstract: A method for decoding a stream having first and second portions portion and representing an image divided into blocks. The method includes a sequence test having a predetermined non-zero number of bits, including two at the power of the predetermined number (2N) iterations of the following substeps, for a current block: obtaining a sequence distinct from sequences already tested; decoding and reconstructing a version of the current block from the obtained sequence and from coded data in the first portion; evaluating a likelihood measurement associated with the reconstructed block; decoding information characteristic of a first sequence including the predetermined number of binary symbols from the second portion; selecting a sequence from the sequences tested, based on the likelihood measurements and the decoded information, the selected sequence being identified as the first sequence; and decoding and reconstructing the current block from the first sequence and the first portion.

Abstract: A method for composing an intermediate representation of a video sequence from at least two different representations of the video sequence, the at least two representations being spatially partitioned into a plurality of tiles, each tile being associated with compressed data in the representation. The method is such that the tiles can be decoded independently from one another and at a given time the various representations are partitioned identically. The method includes selecting, according to at least one selection criterion, a set of tiles forming a partition of the sequence from the at least two representations, and composing an intermediate representation of the video sequence from compressed data associated with the selected set of tiles. The method can be implemented in a video decoding terminal or broadcasting server.

Abstract: A method is provided for coding at least one image split up into partitions, a current partition to be coded containing data, at least one data item of which is allotted a sign. The coding method includes, for the current partition, the following steps: calculating the value of a function representative of the data of the current partition with the exclusion of the sign; comparing the calculated value with a predetermined value of the sign; as a function of the result of the comparison, modifying or not modifying at least one of the data items of the current partition, in the case of modification, coding the at least one modified data item.

Abstract: A method for encoding an image having been cut up into partitions. The method includes: predicting data of a current partition based on an already encoded and then decoded reference partition, generating a predicted partition; determining residual data by comparing data relating to the current partition with the predicted partition, the residual data associated with various digital data items. Prior producing a signal containing the encoded information, performing the following steps: determining, from the predetermined residual data, a subset containing residual data capable of being modified; calculating the value of a function representative of the residual data; comparing the calculated value with a value of at least one of the digital data items; based on the comparison, modification or non-modification of at least one of the residual data items of the subset; and, in the event of a modification, entropy encoding the at least one modified residual data item.

Abstract: A method for decoding a signal of encoded digital data, which includes, for at least one part of the signal: determining information representing a characteristic of the encoded data contained in the at least one signal part; determining first and second values of at least one datum required for the decoding of the data; decoding the data based on the first value to obtain a first characteristic of the decoded data; decoding the data based on the second value to obtain a second characteristic of the decoded data; selecting the first or the second value according to the information representing a characteristic of the encoded data and according to the first and second characteristics of the decoded data; and reconstructing the data based on the first or the second value, which has been selected.

Abstract: A method for encoding a digital image divided into a plurality of blocks of pixels. The method includes, for a current block: processing the current block to provide a set of description elements; selecting a subset of description elements to be predicted; ordering the description elements of the subset into an ordered sequence; and encoding the elements of the sequence. Encoding includes scrolling the elements of the sequence and includes, for a current element: selecting a combination of predicted values of the description elements of the current sequence from a plurality of possible combinations based on a predetermined cost criterion and from the second element, values of description elements previously processed of the initial sequence; predicting the current element of the sequence by its value in the selected combination; and encoding an indicator representative of a difference between the actual value of the current element and its predicted value.

Abstract: A method of coding an image comprising the steps of partitioning (C1, C2) the image into a plurality of blocks (CTU1, CTU2, . . . , CTUi, . . . , CTUs) able to contain symbols belonging to a predetermined set of symbols, of entropy coding of a current block on the basis of at least one probability of symbol occurrence and of predictive coding of a compression parameter (QP) associated with said current block.

Abstract: A method for processing a sequence of digital images. The method includes, for a current group: a) forming a main group including original images partitioned into spatial areas and including a watermarking zone; b) obtaining a main bitstream representing an area-based encoding of the images of the main group, in which for an area other than the watermarking area, the pixels of that zone are not predicted with reference to pixels in the watermarking area; c) for the watermarking area: forming a secondary group of images having the same temporal dimension as the main group and spatial dimensions equal to those of the watermarking area, inserting a first watermarking information value into the secondary group, and obtaining a first secondary bitstream representing images of the encoded secondary group including the first watermarking information value; and d) transmitting the main and first secondary bitstreams in the telecommunication network to a client.

Abstract: A method for encoding an image having been cut up into partitions. The method includes: predicting data of a current partition based on an already encoded and then decoded reference partition, generating a predicted partition; determining residual data by comparing data relating to the current partition with the predicted partition, the residual data associated with various digital data items. Prior producing a signal containing the encoded information, performing the following steps; determining, from the predetermined residual data, a subset containing residual data capable of being modified; calculating the value of a function representative of the residual data; comparing the calculated value with a value of at least one of the digital data items; based on the comparison, modification or non-modification of at least one of the residual data items of the subset; and, in the event of a modification, entropy encoding the at least one modified residual data item.

Abstract: A method for coding includes; segmenting an image into blocks; grouping blocks into a number of subsets; coding, using an entropy coding module, each subset, by associating digital information with symbols of each block of a subset, including, for the first block of the image, initializing state variables of the coding module; and generating a data sub-stream representative of at least one of the coded subsets of blocks. Where a current block is the first block to be coded of a subset, symbol occurrence probabilities for the first current block are determined based on those for a coded and decoded predetermined block of at least one other subset. Where the current block is the last coded block of the subset: writing, in the sub-stream representative of the subset, the entire the digital information associated with the symbols during coding of the blocks of the subset, and implementing the initializing sub-step.

Abstract: A method for coding includes; segmenting an image into blocks; grouping blocks into a number of subsets; coding, using an entropy coding module, each subset, by associating digital information with symbols of each block of a subset, including, for the first block of the image, initializing state variables of the coding module; and generating a data sub-stream representative of at least one of the coded subsets of blocks. Where a current block is the first block to be coded of a subset, symbol occurrence probabilities for the first current block are determined based on those for a coded and decoded predetermined block of at least one other subset. Where the current block is the last coded block of the subset: writing, in the sub-stream representative of the subset, the entire the digital information associated with the symbols during coding of the blocks of the subset, and implementing the initializing sub-step.

Abstract: A method for encoding at least one image divided into blocks. The method implements, for a current block to be encoded: determining a first prediction type for the current block; determining a prediction procedure associated with the first prediction type; obtaining a predictor block on the basis of the determined prediction procedure; and calculating a residual block that represents the difference between the predictor block obtained and the current block. The method also includes: selecting a prediction procedure from among a plurality of prediction procedures of a second type, different from the first type; and encoding the residual block calculated by using an encoding parameter determined on the basis of the selected prediction procedure.

Abstract: A method is provided for encoding of at least one image. The encoding method implements, for a current block to be coded for the image: predicting current block according to a prediction procedure selected from among a plurality of predetermined prediction procedures; obtaining a predictor block from the prediction; calculating a first set of data representing a comparison between the predictor block obtained and the current block; comparing the calculated first set with a plurality of quantization vectors; selecting one of the vectors according to a predetermined encoding performance criterion; encoding an index associated with the selected vector; calculating a second set of data representing a comparison between the first calculated data set and the selected vector; and encoding the second calculated data set. During the encoding, at least one of the quantization vectors is modified on the basis of the data from the second calculated data set.

Abstract: A method for coding includes; segmenting an image into blocks; grouping blocks into a number of subsets; coding, using an entropy coding module, each subset, by associating digital information with symbols of each block of a subset, including, for the first block of the image, initializing state variables of the coding module; and generating a data sub-stream representative of at least one of the coded subsets of blocks. Where a current block is the first block to be coded of a subset, symbol occurrence probabilities for the first current block are determined based on those for a coded and decoded predetermined block of at least one other subset. Where the current block is the last coded block of the subset: writing, in the sub-stream representative of the subset, the entire the digital information associated with the symbols during coding of the blocks of the subset, and implementing the initializing sub-step.