histo_2dimhisto_2dimHisto2dimHisto2dimhisto_2dim (Operator)
Name
histo_2dimhisto_2dimHisto2dimHisto2dimhisto_2dim — Calculate the histogram of two-channel gray value images.
Signature
Description
The operator histo_2dimhisto_2dimHisto2dimHisto2dimhisto_2dim calculates the 2-dimensional
histogram of two images within RegionsRegionsRegionsregionsregions. The gray values
of channel 1 (ImageColImageColImageColimageColimage_col) are interpreted as row index,
those of channel 2 (ImageRowImageRowImageRowimageRowimage_row) as column index. The gray
value at one point P(g1,g2) in the output image
Histo2DimHisto2DimHisto2Dimhisto2Dimhisto_2dim indicates the frequency of the gray value
combination (g1,g2) with g1 indicating the line index and g2
the column index.
Attention
Note that the operator histo_2dimhisto_2dimHisto2dimHisto2dimhisto_2dim only considers
the given RegionsRegionsRegionsregionsregions and ignores any previously set domain
of the input images.
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
RegionsRegionsRegionsregionsregions (input_object) region(-array) → objectHRegionHObjectHObjectHobject
Region in which the histogram is to be calculated.
ImageColImageColImageColimageColimage_col (input_object) (multichannel-)image → objectHImageHObjectHObjectHobject (byte / direction / cyclic / int1)
Channel 1.
ImageRowImageRowImageRowimageRowimage_row (input_object) (multichannel-)image → objectHImageHObjectHObjectHobject (byte / direction / cyclic / int1)
Channel 2.
Histo2DimHisto2DimHisto2Dimhisto2Dimhisto_2dim (output_object) image → objectHImageHObjectHObjectHobject * (int4)
Histogram to be calculated.
Example (HDevelop)
read_image(Image,'monkey')
get_domain (Image, Domain)
gauss_filter (Image, ImageGauss, 7)
histo_2dim(Domain,ImageGauss, Image,Histo2Dim)
dev_display(Histo2Dim)
Example (C)
read_image(&Image,"monkey");
get_domain (Image, &Domain)
gauss_filter(Image,&ImageGauss,7);
histo_2dim(Domain,Image,ImageGauss,&Histo2Dim);
set_part(WindowHandle,0,0,511,511);
disp_image(Histo2Dim,WindowHandle);
Example (HDevelop)
read_image(Image,'monkey')
get_domain (Image, Domain)
gauss_filter (Image, ImageGauss, 7)
histo_2dim(Domain,ImageGauss, Image,Histo2Dim)
dev_display(Histo2Dim)
Example (HDevelop)
read_image(Image,'monkey')
get_domain (Image, Domain)
gauss_filter (Image, ImageGauss, 7)
histo_2dim(Domain,ImageGauss, Image,Histo2Dim)
dev_display(Histo2Dim)
Complexity
If F is the plane of the region, the runtime complexity is
O(F + 256^2).
Result
The operator histo_2dimhisto_2dimHisto2dimHisto2dimhisto_2dim returns the value 2 (
H_MSG_TRUE)
if both
images have defined gray values. The behavior in case of empty
input (no input images available) is set via the operator
set_system(::'no_object_result',<Result>:)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>), the behavior
in case of empty region is set via
set_system(::'empty_region_result',<Result>:)set_system("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)set_system("empty_region_result",<Result>).
If necessary an exception is raised.
Possible Predecessors
decompose3decompose3Decompose3Decompose3decompose3,
decompose2decompose2Decompose2Decompose2decompose2,
draw_regiondraw_regionDrawRegionDrawRegiondraw_region
Possible Successors
thresholdthresholdThresholdThresholdthreshold,
class_2dim_supclass_2dim_supClass2dimSupClass2dimSupclass_2dim_sup,
pouringpouringPouringPouringpouring,
local_maxlocal_maxLocalMaxLocalMaxlocal_max,
gray_skeletongray_skeletonGraySkeletonGraySkeletongray_skeleton
Alternatives
gray_histogray_histoGrayHistoGrayHistogray_histo,
gray_histo_absgray_histo_absGrayHistoAbsGrayHistoAbsgray_histo_abs
See also
get_grayvalget_grayvalGetGrayvalGetGrayvalget_grayval
Module
Foundation