find_rectification_grid — Segment the rectification grid region in the image.
find_rectification_grid searches in the image Image for image parts that contain the rectification grid and returns them in the region GridRegion. To do so, essentially image areas with a contrast of at least MinContrast are extracted and the holes in these areas are filled up. Then, an opening with the radius Radius is applied to these areas to eliminate smaller areas of high contrast.
During grid-rectification, a careful reduction of the input region to those image parts that actually contain the rectification grid is useful for two purposes: First, the computing time can be reduced and secondly, saddle_points_sub_pix and connect_grid_points can be prevented from detecting false grid points and connecting lines.
Output region containing the rectification grid.
Default value: 8.0
Suggested values: 2.0, 4.0, 8.0, 16.0, 32.0
Restriction: MinContrast >= 0
Radius of the circular structuring element.
Default value: 7.5
Suggested values: 1.5, 2.5, 3.5, 4.5, 5.5, 7.5, 9.5, 12.5, 15.5, 19.5, 25.5, 33.5, 45.5, 60.5, 110.5
Restriction: Radius >= 0.5
find_rectification_grid (Image, GridRegion, 8, 10) dilation_circle (GridRegion, GridRegionDilated, 5.5) reduce_domain (Image, GridRegionDilated, ImageReduced) saddle_points_sub_pix (ImageReduced, 'facet', 1.5, 5, Row, Column) connect_grid_points (ImageReduced, ConnectingLines, Row, Column, 1.1, 5.5) gen_grid_rectification_map (ImageReduced, ConnectingLines, Map, Meshes, 20, \ 'auto', Row, Column, 'bilinear') map_image (Image, Map, ImageMapped)
find_rectification_grid returns 2 (H_MSG_TRUE) if all parameter values are correct. If necessary, an exception is raised.