Abstract:
A method is provided for encoding an image represented by a sequence of symbols. The method includes the following steps: defining subsequences within the sequence; and going through the subsequences applying the following sub-steps for a routine subsequence: determining an adjacent routine encoded group including two previously encoded subsequences, one of which belongs to an adjacent encoded group associated with a subsequence that is separate from the routine subsequence; initializing a routine probability of occurrence of a symbol, taking into account two known probabilities of occurrence of the symbol, relating to two previously encoded subsequences of the adjacent routine encoded group; the consecutive entropic encoding of the symbols, and updating the routine probability of occurrence; and storing the routine probability of occurrence after encoding the last symbol.
Abstract:
A method and apparatus are provided for encapsulating a plurality of data substreams encoded in a bit stream, wherein the encoded data substream is obtained by entropy encoding of a symbol subsequence representing an image or a series of images. The method includes grouping data substreams into substream pairs according to an iterative traversal order predetermined from the plurality of substreams, and on the basis of a pair of the substreams, obtaining a symmetrical pair by reversing a data order making up the second substream of the pair. The obtained pairs are then concatenated within a sequence. The binary stream is created by encapsulating the sequence and information related to a number of substreams and related to the sizes of pairs of symmetrical substreams.
Abstract:
A method and apparatus are provided for coding a signal from images, the images being split into sub-blocks of pixels. The method includes grouping at least two sub-blocks into at least one block of larger size, when the sub-blocks comply with at least one predetermined grouping criterion. A prediction is performed by applying at least one mode of motion prediction using at least two distinct motion prediction vectors, for at least one block of larger size, the motion prediction vectors being associated respectively with sub-sets of the block of larger size, comprising at least one of the sub-blocks of the block of larger size. The sub-sets are predefined and distinct.
Abstract:
The invention concerns a method of analyzing a set of data representing physical quantities, including the steps of: decomposition (E20) of the set of data on a plurality of resolution levels, first segmentation (E21) of at least one sub-part of a given resolution level, into at least two homogeneous regions, said given resolution level not being the highest resolution level in the decomposition, characterized in that it includes the steps of: extraction (E81) of contour data from the result of the segmentation of the previous steps, second segmentation (E25) of at least one sub-part of the resolution level higher than the given level into at least one homogeneous region, as a function of the contour data extracted.
Abstract:
A method and apparatus for encoding a sequence of images by predicting at least one current image by forward motion compensation from at least one reference image. Prediction implements, for at least one current block of the current image: forward projection of a block of the reference image on the current image, delivering a projected block at least partially overlapping the current block; partitioning the current block delivering a sub-block at least partially overlapped by at least one projected block; and at least one iteration of the following steps for at least one overlapped sub-block: checking that the overlapped sub-block complies with a predetermined allotting criterion; with a positive check, allotting, to the overlapped sub-block, one of the projected motion vectors; and with a negative check, and so long as a predetermined minimum size is not reached for the overlapped sub-block: partitioning of the overlapped sub-block.
Abstract:
A method and apparatus are provided for encoding an image sequence and outputting a signal having a layered organization with at least a base layer and an enhancement layer. For at least one current image of the sequence, the method includes constructing a hierarchical epitome associated with the enhancement layer corresponding to a maximum resolution level of the current image, using: an epitome associated with the enhancement layer corresponding to the maximum resolution level of the current image; and at least one epitome associated with a preceding layer corresponding to a resolution level lower than the maximum resolution level of the current image.
Abstract:
A method is provided for coding an image sequence, including splitting a current image into blocks of standard size, termed macroblocks. For at least one current macroblock of the current image, the method further includes: constructing at least one block of greater size than the current macroblock, termed a large block, which includes the current macroblock and at least one neighbor macroblock in the current image, taking account of characteristics of the current image; coding the large block, delivering base coding information, making it possible to reconstruct a base layer of said current image, and for at least one large block, determining enhancement information associated with at least one macroblock present in the large block.
Abstract:
A method of coding an image or a sequence of images generating a flow of data in the form of groups of blocks, at least one group of blocks containing image blocks having a resolution and a quality level of identical quantification, the method including the following steps for the at least one group of blocks, of a) a first coding so that each block of the at least one group of blocks has at least one associated parameter that is given a first value, and b) a second coding for giving the associated parameter for at least one block of the at least one group of blocks a second value, so that for the at least one block, the first and second values given for the parameter can be combined during decoding to provide a value assigned to the parameter.
Abstract:
Techniques are provided for encoding and decoding image data. The techniques implement a prediction of data of a current block based on at least one already encoded block or reference block, wherein said prediction step takes into account a set of encoded blocks adjacent to said current block and including blocks that have not yet been considered according to said writing path order. Encoding includes the steps of: generating a dependence tree associating a current block with at least one reference block from which the predicted block associated with the current block has been predetermined; and inserting information representative of said dependence tree into said set of data associated with each block.
Abstract:
The invention relates to a method of and a device for coding data in a scalable stream organized in units, characterized in that an indication is given in the header of an SVC NAL unit as to whether this NAL unit can be truncated or not in an adaptation operation for the scalable stream concerned