select_contours_xldselect_contours_xldSelectContoursXldSelectContoursXldselect_contours_xld (Operator)

Name

select_contours_xldselect_contours_xldSelectContoursXldSelectContoursXldselect_contours_xld — Select XLD contours according to several features.

Signature

Description

select_contours_xldselect_contours_xldSelectContoursXldSelectContoursXldSelectContoursXldselect_contours_xld selects XLD contours from the input contours ContoursContoursContoursContourscontourscontours according to the following features (parameter FeatureFeatureFeatureFeaturefeaturefeature):

'contour_length'"contour_length""contour_length""contour_length""contour_length""contour_length":

all contours whose length is smaller than Min1Min1Min1Min1min1min_1 or larger than Max1Max1Max1Max1max1max_1 are not returned (Min2Min2Min2Min2min2min_2 and Max2Max2Max2Max2max2max_2 have no influence here).

'maximum_extent'"maximum_extent""maximum_extent""maximum_extent""maximum_extent""maximum_extent":

all contours whose maximum extent (as measured by their eight extremal points in row and column direction, according to Haralick and Shapiro: Computer and Robot Vision, Addison-Wesley 1992, chapter 3.2) is smaller than Min1Min1Min1Min1min1min_1 or larger than Max1Max1Max1Max1max1max_1 are not returned (Min2Min2Min2Min2min2min_2 and Max2Max2Max2Max2max2max_2 have no influence here).

'direction'"direction""direction""direction""direction""direction":

only contours for which the direction of the regression line is between Min1Min1Min1Min1min1min_1 and Max1Max1Max1Max1max1max_1 (in radians, counter-clockwise) are returned. Min1Min1Min1Min1min1min_1 and Max1Max1Max1Max1max1max_1 are mapped to the range of [0,2*PI[. (Min2Min2Min2Min2min2min_2 and Max2Max2Max2Max2max2max_2 have no influence here).

'curvature'"curvature""curvature""curvature""curvature""curvature":

only contours for which the mean distance from the regression line lies between Min1Min1Min1Min1min1min_1 and Max1Max1Max1Max1max1max_1, and for which the standard deviation of the distances is between Min2Min2Min2Min2min2min_2 and Max2Max2Max2Max2max2max_2 are returned.

'closed'"closed""closed""closed""closed""closed":

only contours for which the distance between their start point and their end point is less or equal Max1Max1Max1Max1max1max_1 pixels are returned. (Min1Min1Min1Min1min1min_1, Min2Min2Min2Min2min2min_2 and Max2Max2Max2Max2max2max_2 have no influence here.)

'open'"open""open""open""open""open":

only contours for which the distance between their start point and their end point is greater than Min1Min1Min1Min1min1min_1 pixels are returned. (Max1Max1Max1Max1max1max_1, Min2Min2Min2Min2min2min_2 and Max2Max2Max2Max2max2max_2 have no influence here).

If Min1Min1Min1Min1min1min_1 = Max1Max1Max1Max1max1max_1 = 0 or Min2Min2Min2Min2min2min_2 = Max2Max2Max2Max2max2max_2 = 0 is used for the selection according to curvature, the respective feature has no influence on the selection.

Attention

Before contour can be filtered by select_contours_xldselect_contours_xldSelectContoursXldSelectContoursXldSelectContoursXldselect_contours_xld according to 'direction'"direction""direction""direction""direction""direction" or 'curvature'"curvature""curvature""curvature""curvature""curvature", the parameters of the regression lines to the contours must be calculated with regress_contours_xldregress_contours_xldRegressContoursXldRegressContoursXldRegressContoursXldregress_contours_xld. If this has not been done, select_contours_xldselect_contours_xldSelectContoursXldSelectContoursXldSelectContoursXldselect_contours_xld calls regress_contours_xldregress_contours_xldRegressContoursXldRegressContoursXldRegressContoursXldregress_contours_xld internally with the parameters ModeModeModeModemodemode = 'no'"no""no""no""no""no" and IterationsIterationsIterationsIterationsiterationsiterations = 1. If a different mode should be used, regress_contours_xldregress_contours_xldRegressContoursXldRegressContoursXldRegressContoursXldregress_contours_xld must be called explicitly.

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Processed without parallelization.

Parameters

Possible Predecessors

regress_contours_xldregress_contours_xldRegressContoursXldRegressContoursXldRegressContoursXldregress_contours_xld

See also

get_contour_xldget_contour_xldGetContourXldGetContourXldGetContourXldget_contour_xld, get_contour_attrib_xldget_contour_attrib_xldGetContourAttribXldGetContourAttribXldGetContourAttribXldget_contour_attrib_xld, gen_contours_skeleton_xldgen_contours_skeleton_xldGenContoursSkeletonXldGenContoursSkeletonXldGenContoursSkeletonXldgen_contours_skeleton_xld, lines_gausslines_gaussLinesGaussLinesGaussLinesGausslines_gauss, lines_facetlines_facetLinesFacetLinesFacetLinesFacetlines_facet, edges_sub_pixedges_sub_pixEdgesSubPixEdgesSubPixEdgesSubPixedges_sub_pix, get_regress_params_xldget_regress_params_xldGetRegressParamsXldGetRegressParamsXldGetRegressParamsXldget_regress_params_xld, get_contour_global_attrib_xldget_contour_global_attrib_xldGetContourGlobalAttribXldGetContourGlobalAttribXldGetContourGlobalAttribXldget_contour_global_attrib_xld, query_contour_global_attribs_xldquery_contour_global_attribs_xldQueryContourGlobalAttribsXldQueryContourGlobalAttribsXldQueryContourGlobalAttribsXldquery_contour_global_attribs_xld

References

R. Haralick, L. Shapiro: “Computer and Robot Vision” Vol. 1; Kapitel 3.2, Addison-Wesley 1992

Module

Foundation