| 摘要 |
The method involves removing a bottom surface of relief from an image of a geographical area using removing units (8), where the relief illustrates small variations in altitudes of the geographical area. A thresholding step is performed to form a binary image, which contains the relief having heights above a threshold value. Rough contours of the heights of the relief are extracted from the binary image using extracting units (11). The contours are simplified by using simplifying units (13) to obtain a set of polygons illustrating the contours of the heights of the relief. An independent claim is also included for a device for automatically determining contours of heights of relief of a geographical area. |
