get_grayval_contour_xldget_grayval_contour_xldGetGrayvalContourXldGetGrayvalContourXld (Operator)

Name

get_grayval_contour_xldget_grayval_contour_xldGetGrayvalContourXldGetGrayvalContourXld — Return gray values of an image at the positions of an XLD contour.

Signature

get_grayval_contour_xld(Image, Contour : : Interpolation : Grayval)

Herror get_grayval_contour_xld(const Hobject Image, const Hobject Contour, const char* Interpolation, double* Grayval)

Herror T_get_grayval_contour_xld(const Hobject Image, const Hobject Contour, const Htuple Interpolation, Htuple* Grayval)

void GetGrayvalContourXld(const HObject& Image, const HObject& Contour, const HTuple& Interpolation, HTuple* Grayval)

HTuple HImage::GetGrayvalContourXld(const HXLDCont& Contour, const HString& Interpolation) const

HTuple HImage::GetGrayvalContourXld(const HXLDCont& Contour, const char* Interpolation) const

HTuple HImage::GetGrayvalContourXld(const HXLDCont& Contour, const wchar_t* Interpolation) const   (Windows only)

static void HOperatorSet.GetGrayvalContourXld(HObject image, HObject contour, HTuple interpolation, out HTuple grayval)

HTuple HImage.GetGrayvalContourXld(HXLDCont contour, string interpolation)

Description

The operator get_grayval_contour_xldget_grayval_contour_xldGetGrayvalContourXldGetGrayvalContourXldGetGrayvalContourXld returns interpolated gray values at several subpixel positions of the ImageImageImageImageimage. The coordinates of the positions are specified via one XLD contour ContourContourContourContourcontour. The gray values are returned in GrayvalGrayvalGrayvalGrayvalgrayval.

The interpolation method can be selected via the parameter InterpolationInterpolationInterpolationInterpolationinterpolation:

'nearest_neighbor'"nearest_neighbor""nearest_neighbor""nearest_neighbor""nearest_neighbor":

The results are the gray values of the nearest pixels to the selected coordinates. For images of type byte, direction, cyclic, uint2, int1, int2, int4, and int8, the parameter GrayvalGrayvalGrayvalGrayvalgrayval is a tuple of integer numbers. For images of type real and complex, the parameter GrayvalGrayvalGrayvalGrayvalgrayval is a tuple of floating point numbers.

'bilinear'"bilinear""bilinear""bilinear""bilinear":

The parameter GrayvalGrayvalGrayvalGrayvalgrayval is computed using a bilinear interpolation of the four neighboring gray values of the selected coordinates. The result is a tuple of floating point numbers. The runtime increases significantly compared to 'nearest_neighbor'"nearest_neighbor""nearest_neighbor""nearest_neighbor""nearest_neighbor". Direction and cyclic images are treated like byte images.

'bicubic'"bicubic""bicubic""bicubic""bicubic":

The parameter GrayvalGrayvalGrayvalGrayvalgrayval is computed using a bicubic interpolation of sixteen neighboring gray values of the selected coordinates. The result is a tuple of floating point numbers. The runtime increases significantly compared to 'bilinear'"bilinear""bilinear""bilinear""bilinear". Direction and cyclic images are treated like byte images. In this mode, the resulting gray values may contain values that lie outside of the range of numbers that can be represented by the input image type.

'bicubic_clipped'"bicubic_clipped""bicubic_clipped""bicubic_clipped""bicubic_clipped":

The parameter GrayvalGrayvalGrayvalGrayvalgrayval is computed using a bicubic interpolation of sixteen neighboring gray values of the selected coordinates. The result is a tuple of floating point numbers. The runtime increases significantly compared to 'bilinear'"bilinear""bilinear""bilinear""bilinear". Direction and cyclic images are treated like byte images. In this mode, resulting gray values that lie outside of the range of numbers that can be represented by the input image type are clipped to that range.

Note that get_grayval_contour_xldget_grayval_contour_xldGetGrayvalContourXldGetGrayvalContourXldGetGrayvalContourXld does not take the domain of the image into account, i.e., if the domain has been reduced, e.g., with reduce_domainreduce_domainReduceDomainReduceDomainReduceDomain, gray values are returned even for points that lie outside the domain.

Please note also that each point of the XLD contour must be in the range -0.5 <= row coordinate < height(ImageImageImageImageimage)-0.5 and -0.5 <= column coordinate < width(ImageImageImageImageimage)-0.5.

Execution Information

Parameters

ImageImageImageImageimage (input_object)  singlechannelimage objectHImageHImageHobject (byte / direction / cyclic / int1 / int2 / uint2 / int4 / real / complex)

Image whose gray values are to be accessed.

ContourContourContourContourcontour (input_object)  xld_cont objectHXLDContHXLDContHobject

Input XLD contour with the coordinates of the positions.

InterpolationInterpolationInterpolationInterpolationinterpolation (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Interpolation method.

Default value: 'nearest_neighbor' "nearest_neighbor" "nearest_neighbor" "nearest_neighbor" "nearest_neighbor"

List of values: 'bicubic'"bicubic""bicubic""bicubic""bicubic", 'bicubic_clipped'"bicubic_clipped""bicubic_clipped""bicubic_clipped""bicubic_clipped", 'bilinear'"bilinear""bilinear""bilinear""bilinear", 'nearest_neighbor'"nearest_neighbor""nearest_neighbor""nearest_neighbor""nearest_neighbor"

GrayvalGrayvalGrayvalGrayvalgrayval (output_control)  grayval(-array) HTupleHTupleHtuple (real / integer) (double / int / long) (double / Hlong) (double / Hlong)

Gray values of the selected image coordinates.

Result

If the parameters are valid, the operator get_grayval_contour_xldget_grayval_contour_xldGetGrayvalContourXldGetGrayvalContourXldGetGrayvalContourXld returns the value 2 (H_MSG_TRUE). If necessary, an exception is raised.

Possible Predecessors

read_imageread_imageReadImageReadImageReadImage, draw_xlddraw_xldDrawXldDrawXldDrawXld, gen_contour_polygon_xldgen_contour_polygon_xldGenContourPolygonXldGenContourPolygonXldGenContourPolygonXld, edges_sub_pixedges_sub_pixEdgesSubPixEdgesSubPixEdgesSubPix

Alternatives

get_grayval_interpolatedget_grayval_interpolatedGetGrayvalInterpolatedGetGrayvalInterpolatedGetGrayvalInterpolated

Module

Foundation