find_rectification_grid — Segment the rectification grid region in the image.
find_rectification_grid(Image : GridRegion : MinContrast, Radius : )
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.
Image (input_object) singlechannelimage → object (byte / uint2)
Input image.
GridRegion (output_object) region → object
Output region containing the rectification grid.
MinContrast (input_control) number → (real / integer)
Minimum contrast.
Default: 8.0
Suggested values: 2.0, 4.0, 8.0, 16.0, 32.0
Restriction:
MinContrast >= 0
Radius (input_control) real → (real / integer)
Radius of the circular structuring element.
Default: 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. 如有必要，将引发异常。
dilation_circle,
reduce_domain
Calibration