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
Abstract:
A method is provided for filtering a scalable video stream, organized in the form of data unit blocks, each of which comprises a base data unit and a set of data units distributed according to two types of enhancement data, corresponding respectively to time and/or space and/or quality characteristics and making it possible to define several quality levels. The method defines at least two distinct filtering profiles, or paths of each block data units, wherein each path defines a row of successive foldover positions and each foldover position uses at least by one less data units than a previous position, and selects one of the paths according to a predetermined criterion, taking into account the type of content of the stream and/or at least one information item representing the capacities of a terminal receiving the stream.
Abstract:
A video image sequence is coded or decoded. By motion compensated temporal filtering, using discrete wavelet decomposition, the discrete wavelet is decomposed by dividing the video image sequence into source and destination groups of images. An image in the destination group is determined from at least one image including pixels in the first group of the source group. The representative image includes pixels and subpixels determined from pixels and subpixels obtained by upsampling at least one image in the source group.
Abstract:
The invention proposes a method of inserting a message in a subset (VO) of digital data representing physical quantities, characterized in that it includes the steps of: estimating (E4) a capacity to receive a message for said subset, selecting (E5) a message with a size less than or equal to the estimated capacity, in a set of a messages, inserting (E6) the selected message in the said subset of digital data. The invention applies particularly to an object in a digital image.