| 摘要 |
Image data (1) is filtered by determining, for each of a first plurality of points (4, 5) within the image data, which of a plurality of directions is the direction along which a line of samples containing the point has the least variation according to a predetermined measure of variation. This generates data representing a vector field. For each of a second plurality of points (4, 5) within the image data, (i) the vector field is integrated to determine a streamline or streamline segment from the point, and (ii) a filtered value for the point is determined by applying a filtering operation to the image data using a filtering kernel oriented along the streamline or streamline segment. |
