mod_parallels_xldmod_parallels_xldModParallelsXldModParallelsXld (Operator)


mod_parallels_xldmod_parallels_xldModParallelsXldModParallelsXld — Extract parallel XLD polygons enclosing a homogeneous area.


mod_parallels_xld(Parallels, Image : ModParallels, ExtParallels : Quality, MinGray, MaxGray, MaxStandard : )

Herror mod_parallels_xld(const Hobject Parallels, const Hobject Image, Hobject* ModParallels, Hobject* ExtParallels, double Quality, const Hlong MinGray, const Hlong MaxGray, double MaxStandard)

Herror T_mod_parallels_xld(const Hobject Parallels, const Hobject Image, Hobject* ModParallels, Hobject* ExtParallels, const Htuple Quality, const Htuple MinGray, const Htuple MaxGray, const Htuple MaxStandard)

void ModParallelsXld(const HObject& Parallels, const HObject& Image, HObject* ModParallels, HObject* ExtParallels, const HTuple& Quality, const HTuple& MinGray, const HTuple& MaxGray, const HTuple& MaxStandard)

HXLDModPara HXLDPara::ModParallelsXld(const HImage& Image, HXLDExtPara* ExtParallels, const HTuple& Quality, Hlong MinGray, Hlong MaxGray, const HTuple& MaxStandard) const

HXLDModPara HXLDPara::ModParallelsXld(const HImage& Image, HXLDExtPara* ExtParallels, double Quality, Hlong MinGray, Hlong MaxGray, double MaxStandard) const

static void HOperatorSet.ModParallelsXld(HObject parallels, HObject image, out HObject modParallels, out HObject extParallels, HTuple quality, HTuple minGray, HTuple maxGray, HTuple maxStandard)

HXLDModPara HXLDPara.ModParallelsXld(HImage image, out HXLDExtPara extParallels, HTuple quality, int minGray, int maxGray, HTuple maxStandard)

HXLDModPara HXLDPara.ModParallelsXld(HImage image, out HXLDExtPara extParallels, double quality, int minGray, int maxGray, double maxStandard)


mod_parallels_xldmod_parallels_xldModParallelsXldModParallelsXldModParallelsXld selects XLD parallels enclosing homogeneous areas from the input parallels ParallelsParallelsParallelsParallelsparallels. The parameter ImageImageImageImageimage contains the corresponding gray value image.

Only parallels having a quality factor larger than QualityQualityQualityQualityquality are examined. The algorithm performs parallel cross sections one pixel apart, and parallel to the line segments in the area of overlap between two parallel line segments.

In the first iteration, the mean gray value for each of the lines in the cross section is calculated. In the second iteration, the standard deviations of the gray values along each line are computed.

If the mean gray value of an area between parallels lies in the interval [MinGrayMinGrayMinGrayMinGrayminGray,MaxGrayMaxGrayMaxGrayMaxGraymaxGray], and if the mean of all standard deviations is smaller than the upper threshold MaxStandardMaxStandardMaxStandardMaxStandardmaxStandard, the corresponding parallels are returned as modified parallels in ModParallelsModParallelsModParallelsModParallelsmodParallels.

In a second step, all polygon segments adjacent to parallels bordering homogeneous areas are checked for homogeneity. To do so, a rectangle having the width of the last area enclosed by a modified parallel is constructed, and checked for homogeneity using the algorithm described above. This process is continued as long as there are adjacent polygon segments. The polygons thus found are returned as extended parallels in ExtParallelsExtParallelsExtParallelsExtParallelsextParallels.

Execution Information


ParallelsParallelsParallelsParallelsparallels (input_object)  xld_para-array objectHXLDParaHXLDParaHobject

Input XLD parallels.

ImageImageImageImageimage (input_object)  singlechannelimage objectHImageHImageHobject (byte)

Corresponding gray value image.

ModParallelsModParallelsModParallelsModParallelsmodParallels (output_object)  xld_mod_para-array objectHXLDModParaHXLDModParaHobject *

Modified XLD parallels.

ExtParallelsExtParallelsExtParallelsExtParallelsextParallels (output_object)  xld_ext_para-array objectHXLDExtParaHXLDExtParaHobject *

Extended XLD parallels.

QualityQualityQualityQualityquality (input_control)  number HTupleHTupleHtuple (real / integer) (double / int / long) (double / Hlong) (double / Hlong)

Minimum quality factor (measure of parallelism).

Default value: 0.4

Suggested values: 0.1, 0.2, 0.3, 0.4, 0.5, 0.6

Restriction: 0.0 <= Quality && Quality <= 1.0

MinGrayMinGrayMinGrayMinGrayminGray (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Minimum mean gray value.

Default value: 160

Suggested values: 80, 100, 120, 140, 160, 180

Restriction: 0 <= MinGray && MinGray <= 255

MaxGrayMaxGrayMaxGrayMaxGraymaxGray (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Maximum mean gray value.

Default value: 220

Suggested values: 140, 160, 180, 200, 220, 240

Restriction: 0 <= MaxGray && MaxGray <= 255 && MaxGray >= MinGray

MaxStandardMaxStandardMaxStandardMaxStandardmaxStandard (input_control)  number HTupleHTupleHtuple (real / integer) (double / int / long) (double / Hlong) (double / Hlong)

Maximum allowed standard deviation.

Default value: 10.0

Suggested values: 5.0, 10.0, 15.0, 20.0

Restriction: MaxStandard >= 0.0

Possible Predecessors


Possible Successors


See also