Abstract: A method for decoding at least one encoded image within an encoded data stream, the image being split into blocks of elements. The decoding method includes: obtaining from the stream a piece of information representative of a so-called prediction function, the prediction function belonging to a predetermined list of prediction functions; and decoding at least one element of a block of elements, using a differential pulse-code modulation, from an already processed neighbouring element and using the prediction function.

Abstract: A method for encoding or decoding at least one image, an image being split into blocks of elements. The method includes, for at least one block: splitting the block into at least two areas; and processing at least one of the areas. The processing includes scanning the elements of the area according to a predetermined scanning order, and for at least one scanned element, called a current element: selecting at least one predictor element previously encoded or decoded according to a prediction function; and predicting the current element: from the at least one predictor element, if the at least one predictor element belongs to the area; or from at least one replacement value, otherwise.

Abstract: A method for decoding a data stream representative of an image split into blocks. The method includes: for a current block, determining whether the size of the current block is less than or equal to a threshold, and if so, decoding information indicating a coding mode of the block among first and second coding modes, and reconstructing the current block according to the indicated coding mode, and otherwise reconstructing according to the first coding mode. According to the first coding mode, the current block is reconstructed using an inverse transform of a transformed prediction residue decoded for the current block, and according to the second coding mode the current block is reconstructed, for each pixel, by obtaining a prediction of the pixel from another previously decoded pixel belonging to the current block or to a previously decoded block, and reconstructing the pixel from the prediction and a decoded prediction residue.

Abstract: A method for decoding a data stream representative of an image split into blocks. For a current block of the image, an item of information indicating a coding mode among a first and a second coding mode of the current block is decoded from the data stream and the current block is decoded depending on this information. When the coding mode of the current block corresponds to the second coding mode, the current block is reconstructed from a prediction obtained, for each pixel, from another previously decoded pixel belonging to the current block or to a previously decoded block of the image, and from a decoded residue associated with the pixel. At least one processing method is applied to the reconstructed current block for at least one pixel of the current block depending on the coding mode of the current block and/or the coding mode of the neighbouring blocks.

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 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 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 coding a digital image divided into blocks. The method includes, for a current block: processing the current block to provide a vector of transformed coefficients; selecting a sequence of M signs of coefficients to be predicted in the coefficient vector, M being an integer greater than or equal to 2; predicting values of the signs from a plurality of assumptions of combinations and a cost function; and for a sign of the sequence, coding an indicator representing a difference between its actual value and its predicted value. The predicting includes, for at least one second, current assumption: obtaining a pixel vector associated with the current assumption, by linear combination of at least one pixel vector associated with a first assumption and at least one pattern vector obtained from the vector of transformed coefficients; an calculating the cost function for the current assumption from the pixel vector obtained.

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 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 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 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 for coding a digital image divided into blocks. The method includes, for a current block: processing the current block to provide a vector of transformed coefficients; selecting a sequence of M signs of coefficients to be predicted in the coefficient vector, M being an integer greater than or equal to 2; predicting values of the signs from a plurality of assumptions of combinations and a cost function; and for a sign of the sequence, coding an indicator representing a difference between its actual value and its predicted value. The predicting includes, for at least one second, current assumption: obtaining a pixel vector associated with the current assumption, by linear combination of at least one pixel vector associated with a first assumption and at least one pattern vector obtained from the vector of transformed coefficients; an calculating the cost function for the current assumption from the pixel vector obtained.

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 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 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 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.