Abstract: In the method of motion estimation a tree (120) of segments (102-114) of an image (100) is generated by performing a hierarchical segmentation. The tree (120) of segments is analyzed to control the generation of a set (118) of candidate motion vectors of a segment (104). For the motion vectors of the set (118) match penalties are calculated. Finally, a particular motion vector (116) is selected from the set (118) of candidate motion vectors on the basis of match penalties. In the method of depth estimation depth data is calculated on the basis of a motion vector and the rules of parallax.

Abstract: A method of generating a three-dimensional representation (904) of at least one object (916) from multiple two-dimensional images (912) of the object makes use of an octree (902) of cells (903) to hold the three-dimensional representation (904), with each cell comprising vertices (906) and edges (910) connecting the vertices. The method is based on a process of splitting cells of the octree into smaller cells. A stop criterion for the process of splitting cells is based on inspecting which of the vertices of the cell are inside and which of the vertices are outside the object. Another stop criterion for the process of splitting a cell is based on inspecting whether the vertices of neighboring cells, are inside or outside the object.

Abstract: If an implicit surface (120) is defined by means of values assigned to vertices of a cell-based structure then this implicit surface (120) can be approximated by means of a triangulated surface which can be visualized. The method of approximating an implicit surface (120) by generation of a triangulated surface comprising a plurality of triangles (128) is characterized in that a location of a particular triangle vertex (122) is inside a cell (100) of the cell-based structure. The location of the particular triangle vertex (122) is calculated by means of the values assigned to the cell vertices (102-116) of one or more cells (100,101).

Abstract: A method for matching digital images, including regularization of image features of a first digital image, composed of pixels, defining a finite set of candidate values, wherein a candidate value represents a candidate for a possible match between image features of the first image and a second image, establishing a matching penalty function for evaluation of the candidate values, evaluating the matching penalty function for every candidate value, selection of a candidate value based on the result of the evaluation of the matching penalty function, regularization of the first image by segmentation of the first image, comprising assigning at least part of the pixels of the first image to respective segments, determining a certainty parameter for at least part of the pixels of a segment, and establishing the matching penalty function to be at least partially based on the certainty parameter.

Abstract: A method for segmenting a digital image composed of pixels, including determining hard border fragments in the digital image by means of an edge detection process, determining respective sides of each of said hard border fragments, and forming segments by determining for each pixel a closest side and by uniquely assigning each pixel of said digital image to a single segment, corresponding with the determined closest side to the respective pixel.

Abstract: In block-based motion or depth estimation, a block is assigned a motion or depth value as a result of minimizing the matching error over a limited set of candidate values. The matching error for each element of the set is obtained by computing the luminosity differences between a block of a first image (10) and an area of a second image (11). It may occur that an object (12) is partially obstructed by another object (15), so that a pixel (14) in the block is not present in the corresponding area, because another pixel (16) overlaps it. The method and system according to the invention determine which pixels are not visible in the second image (11), and compute the matching error over only the visible pixels. An apparatus for adapting a video signal (40) uses the chosen candidate values to create an enhanced version of the video signal (40).

Abstract: In block-based motion or depth estimation, a block is assigned a motion or depth value as a result of minimizing the matching error over a limited set of candidate values (21, 22, 23, 24). The curvature (20) of the function of matching error against candidate value, based on this set, can be used as a measure for the strength of the obtained optimal candidate value for motion or depth. If the obtained value is not sufficiently strong, the method and system according to the invention will repeat the process of determining the optimal candidate value until a sufficiently strong value is obtained. An apparatus for adapting a video signal (40) uses the chosen candidate values to create an enhanced version of the video signal (40).