摘要:
The invention concerns a method of inserting a watermark in an image comprising at least three components, the method comprises the steps of decomposing at least one component of the image into detail sub-bands in various directions and comprising coefficients, each coefficient being characterized by its position in the detail sub-band to which it belongs and its amplitude, of determining, for each position, information representing local amplitude variations from the amplitudes of the coefficients at this position in the various detail sub-bands and the coefficients close to this position in the various detail sub-bands, of determining a watermarking strength at each position from the information representing determined local amplitude variations in the said position and inserting a watermark composed of a plurality of binary information in the image, inserting each item of binary information at a position on the image according to the watermarking strength determined for a position corresponding to the position at which the binary information is inserted.
摘要:
A method of watermarking a color image that has at least three components is provided. Such a method of watermarking includes an insertion step of a mark of watermarking, on at least one point of the image, according to an insertion rule taking into account the relative position of at least three component vectors, associated to said at least one point.
摘要:
The invention concerns a method for coding images using selectively at least two image coding modes, each optimising compression of at least a video sequence image on the basis of different optimisation criteria.
摘要:
The invention relates to motion estimation and compensation between two given images represented by a polygonal mesh. It provides a solution to the problems of crowding and uncovering of mesh units when the mesh is shifted. More specifically, the invention relates to a method for the encoding of a mesh that represents an image of a moving sequence. According to the invention, such a mesh is larger in size than the image.
摘要:
The invention relates to a method for estimating the motion between two digital images and to the use of this method for coding images. The aim of the method is to eliminate the disturbances caused by the mesh being overturned during the motion estimation process. According to the invention, the method consists of carrying out a first motion estimation in order to identify the faulty mesh, i.e. the mesh that is overturning or is overlapping after the displacement vectors have been applied; then carrying out a second motion estimation, excluding at least said faulty mesh, in order to minimize prediction error on the remaining mesh of the model.
摘要:
The invention relates to a femoral prosthesis part, the metaphyseal part of which comprises a series of geometric sections (SA to SG) which are disposed in parallel to the transverse plane at equidistant levels. The aforementioned geometric sections are provided with a quadrilateral shape having strongly rounded summits. The two long sides of said sections converge in the medial direction and each section lies inside a geometric quadrangle which is located in the plane. The four sides of said quadrangle intercept, respectively, four geometric lines (m, l, a, p) which are obtained by projecting the profiles of the internal surface of the cortical bone. The above-mentioned geometric sections pivot in relation to one another in internal rotation from the bottom upwards in order to obtain the desired helitorsion angle.
摘要:
The invention concerns a method which consists in analyzing a field of motion of images, estimated by using a first mesh, to detect a faulty area in the first mesh, and in locating a rupture line in said area; then generating a second mesh including a faultless part consisting of meshes of the first mesh outside the faulty area and two sub-meshes which overlap in a region including the rupture line. Each of the two sub-meshes includes respective meshes delimited by nodes including nodes shared with the faultless part, located at the boundary of the faulty area, and additional nodes not belonging to the faultless part, the rupture line being located between the respective nodes of the two sub-meshes shared with the faultless part. Said second mesh is used to finally estimate the field of motion in the group of images concerned.
摘要:
The invention concerns a method for encoding at least a source image using a hierarchical mesh defining at least two nested spaces corresponding each to a decomposition level of said meshing, which consists, at least at a decomposition level n (except the first decomposition level), in delivering only image coefficients expressed in a base of functions defined in a space orthogonal to the space corresponding to the preceding decomposition level n−1, said functions being selected so that said image coefficients enable to optimize for said decomposition level n the data already transmitted for the preceding decomposition level n−1, so as to produce a reconstructed image, representing said source image, with optimized restoration quality for said decomposition level n.
摘要:
The invention concerns a method of inserting a watermark in an image comprising at least three components, the method comprises the steps of decomposing at least one component of the image into detail sub-bands in various directions and comprising coefficients, each coefficient being characterized by its position in the detail sub-band to which it belongs and its amplitude, of determining, for each position, information representing local amplitude variations from the amplitudes of the coefficients at this position in the various detail sub-bands and the coefficients close to this position in the various detail sub-bands, of determining a watermarking strength at each position from the information representing determined local amplitude variations in the said position and inserting a watermark composed of a plurality of binary information in the image, inserting each item of binary information at a position on the image according to the watermarking strength determined for a position corresponding to the position at which the binary information is inserted.
摘要:
The invention concerns the refinement of a triangular mesh representing a three-dimensional object (3D), said mesh consisting of an arrangement of vertices and triangular surfaces, each defined by three references to the vertices which it links, and having three edges each linking two of said vertices. The invention is characterized in that said method comprises a step which consists in selecting at least a region of interest, said mesh refinement being carried out locally on at least one region of interest.