local_max_cont_xld ( Contours, Image : LocalMaxContours : MinPercent, MinDiff, Distance : )
Select XLD contours with a local maximum of gray values.
local_max_cont_xld selects XLD contours from the
contours passed in Contours, which have a local maximum
in gray values across the direction of the contour. In order to be
selected, at least MinPercent of the contour points must
have a local maximum perpendicular to the direction of the contour.
The contours' direction is determined by fitting a regression line
through five neighboring points of the contour. In order to decide
whether there is a local maximum for a contour point, a gray value
profile Distance points wide and perpendicular to the
contour is computed on both sides of the contour. If the gray value
at the countour point is at least MinDiff larger than the
gray value at at least one point on each side of the profile, the
contour point is labeled as a local maximum. The selected contours
are returned in LocalMaxContours.
Parameters
Contours (input_object)
|
xld_cont-array -> object
|
XLD contours to be examined. |
Image (input_object)
|
image -> object
|
Corresponding gray value image. |
LocalMaxContours (output_object)
|
xld_cont-array -> object
|
Selected contours. |
MinPercent (input_control)
|
number -> integer / real
|
Minumum percentage of maximum points. |
Default value: 70 |
Suggested values: 60, 70, 75, 80, 85, 90, 95 |
Restriction: (0.0 <= MinPercent) && (MinPercent <= 100.0) |
MinDiff (input_control)
|
integer -> integer
|
Minimum amount by which the gray value at the
maximum must be larger than in the profile. |
Default value: 15 |
Suggested values: 5, 8, 10, 12, 15, 20 |
Restriction: (0 <= MinDiff) && (MinDiff <= 255) |
Distance (input_control)
|
integer -> integer
|
Maximum width of profile used to check for maxima. |
Default value: 4 |
Suggested values: 2, 3, 4, 5, 6 |
Restriction: Distance >= 1 |
Possible Predecessors
gen_contour_xld,
gen_contour2_xld,
lines_gauss,
lines_facet,
edges_sub_pix
Possible Successors
poly_xld
See also
smooth_cont_xld
Copyright © 1996-1997 MVTec Software GmbH