摘要:
A method for decoding a stream of coded data representative of a sequence of images is disclosed. The decoding method comprises: determining a prediction block, calculating the average of said prediction block, reconstructing, from said stream, a DC coefficient and AC coefficients relating to said current block, calculating an average of said current block from said average of said prediction block and said DC coefficient, calculating a weighted prediction parameter as being the ratio of the average of said current block and the average of said prediction block, transforming a block of coefficients comprising a null value as DC coefficient and said reconstructed AC coefficients into a residual block, reconstructing the current block by merging said residual block and said prediction block weighted by said weighted prediction parameter. A method for coding is further disclosed.
摘要:
A method for decoding a stream of coded data representative of a sequence of images is disclosed. The decoding method comprisesdetermining a prediction block,calculating the average of said prediction block,reconstructing, from said stream, a DC coefficient and AC coefficients relating to said current block,calculating an average of said current block from said average of said prediction block and said DC coefficient,calculating a weighted prediction parameter as being the ratio of the average of said current block and the average of said prediction block,transforming a block of coefficients comprising a null value as DC coefficient and said reconstructed AC coefficients into a residual block,reconstructing the current block by merging said residual block and said prediction block weighted by said weighted prediction parameter.A method for coding is further disclosed.
摘要:
The process comprising splitting of an image into blocks, intra coding of a current block using spatial prediction based on a matching pursuit algorithm selecting, from a dictionary of atoms, the atom the most correlated with a causal neighborhood of the current block, is characterized in that it performs the following steps: determination of the two dimensional shift between the causal neighborhood and the selected atom, generation of at least, a new phased atom taking into account the values of the two dimensional spatial shift, use of this new atom for intra prediction, according to the matching pursuit algorithm, if better correlated than the selected one. Application to video data compression.
摘要:
A method for coding an image divided into sub-regions is described. The coding method comprises the following steps: extracting from the image sub-regions representative of other sub-regions of the image, coding the sub-regions representative of other sub-regions at a first quality, and coding the other sub-regions at a second quality strictly lower than the first quality.
摘要:
The process comprising splitting of an image into blocks, intra coding of a current block using spatial prediction based on a matching pursuit algorithm selecting, from a dictionary of atoms, the atom the most correlated with a causal neighborhood of the current block, is characterized in that it performs the following steps: — determination of the two dimensional shift between the causal neighborhood and the selected atom, — generation of at least, a new phased atom taking into account the values of the two dimensional spatial shift, — use of this new atom for intra prediction, according to the matching pursuit algorithm, if better correlated than the selected one. Application to video data compression.
摘要:
A method for decoding a video picture comprising coded structured regions and textured regions is disclosed. A reference texture patch is constituted of a part or of blocks of the structured region found around the textured region and the pixels of the textured region are synthesized sequentially according to a spiral type scanning around the textured region, the causal area being found inside the reference texture patch at least for the first round of synthesis.
摘要:
A method for decoding a stream of coded data to reconstruct a current block of a sequence of images is disclosed. The method comprises the steps of: reconstructing for the current block a first item of motion data from a stream of coded data, identifying a first prediction block with the first item of motion data, determining a second item of motion data by template matching, identifying a second prediction block with the second item of motion data, reconstructing the current block from the first and second prediction blocks. The step of determination of the second item of motion data is a function of the first distortion calculated between the first prediction block and the second prediction block.
摘要:
A method for coding a block of pixels is disclosed. The method comprises the following steps: determining, for each pixel of the current block, a prediction pixel by thresholding, with a current threshold value, of coefficients resulting from a transformation applied on a window covering at least the pixel of the current block and by inverse transformation applied to the thresholded coefficients, extracting from the current block a prediction block formed of prediction pixels to generate a residue block, and coding said residue block, According to the invention, the current threshold value is determined or coded from neighboring reconstructed pixels of the current block.
摘要:
The method includes determining at least one candidate motion vector associated with a neighboring block of said current block. A prediction motion vector is determined from the candidate motion vector, and the current block is coded from the prediction motion vector. The prediction motion vector is determined according by determining, for the candidate motion vector, a corrective motion vector so as to minimize a distortion calculated between the neighoboring block successively coded and reconstructed and a prediction block motion compensated by the at least one candidate motion vector modified by the corrective motion vector. The prediction motion vector is then determined from the candidate motion vector modified by the corrective motion vector.
摘要:
The invention is made in the field of image block encoding and reconstruction. A method for reconstructing a current block of an image is described, the current block being encoded using predictive encoding of segments resulting from geometry adaptive block partitioning of said current block. After decoding encoded data comprising at least one flag and motion vectors, wherein blocks referenced by the motion vectors are used for prediction of segments of the current block, the at least one flag and an encoding order of the motion vectors in the encoded data is used for determining which of the referenced blocks exhibits a geometry that matches the geometry of the current block and for determining a segment of the determined block, wherein prior to determining the segment, the determined block is geometry adaptive block partitioned into segments from which the segment is determined for predicting one of the segments of the current block.