noise_distribution_meanT_noise_distribution_meanNoiseDistributionMeanNoiseDistributionMeannoise_distribution_mean (Operator)
Name
noise_distribution_meanT_noise_distribution_meanNoiseDistributionMeanNoiseDistributionMeannoise_distribution_mean — Determine the noise distribution of an image.
Signature
Description
noise_distribution_meannoise_distribution_meanNoiseDistributionMeanNoiseDistributionMeanNoiseDistributionMeannoise_distribution_mean calculates the noise
distribution in a region of the image ImageImageImageImageimageimage. The
parameter ConstRegionConstRegionConstRegionConstRegionconstRegionconst_region determines a region of the image
with approximately constant gray values. Ideally, the changes in
gray values should only be caused by noise in this region. From
this region the noise distribution is determined by using the
mean_imagemean_imageMeanImageMeanImageMeanImagemean_image operator to smooth the image, and to use the gray
value differences in this area as an estimate for the noise
distribution, which is returned in DistributionDistributionDistributionDistributiondistributiondistribution.
Attention
It is important to ensure that the region ConstRegionConstRegionConstRegionConstRegionconstRegionconst_region is
not too close to a large gradient in the image, because the gradient
values are then used for calculating the mean. This means the
distance of ConstRegionConstRegionConstRegionConstRegionconstRegionconst_region must be at least as large as the
filter size FilterSizeFilterSizeFilterSizeFilterSizefilterSizefilter_size used for calculating the mean.
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
ConstRegionConstRegionConstRegionConstRegionconstRegionconst_region (input_object) region(-array) → objectHRegionHObjectHRegionHobject
Region from which the noise distribution is to
be estimated.
ImageImageImageImageimageimage (input_object) singlechannelimage → objectHImageHObjectHImageHobject (byte)
Corresponding image.
FilterSizeFilterSizeFilterSizeFilterSizefilterSizefilter_size (input_control) integer → HTupleintHTupleHtuple (integer) (int / long) (Hlong) (Hlong)
Size of the mean filter.
Default value: 21
Suggested values: 5, 11, 15, 21, 31, 51, 101
Typical range of values: 3
≤
FilterSize
FilterSize
FilterSize
FilterSize
filterSize
filter_size
≤
501 (lin)
Minimum increment: 2
Recommended increment: 2
DistributionDistributionDistributionDistributiondistributiondistribution (output_control) distribution.values-array → HTupleSequence[float]HTupleHtuple (real) (double) (double) (double)
Noise distribution of all input regions.
Possible Predecessors
draw_regiondraw_regionDrawRegionDrawRegionDrawRegiondraw_region,
gen_circlegen_circleGenCircleGenCircleGenCirclegen_circle,
gen_ellipsegen_ellipseGenEllipseGenEllipseGenEllipsegen_ellipse,
gen_rectangle1gen_rectangle1GenRectangle1GenRectangle1GenRectangle1gen_rectangle1,
gen_rectangle2gen_rectangle2GenRectangle2GenRectangle2GenRectangle2gen_rectangle2,
thresholdthresholdThresholdThresholdThresholdthreshold,
erosion_circleerosion_circleErosionCircleErosionCircleErosionCircleerosion_circle,
binomial_filterbinomial_filterBinomialFilterBinomialFilterBinomialFilterbinomial_filter,
gauss_filtergauss_filterGaussFilterGaussFilterGaussFiltergauss_filter,
smooth_imagesmooth_imageSmoothImageSmoothImageSmoothImagesmooth_image,
sub_imagesub_imageSubImageSubImageSubImagesub_image
Possible Successors
add_noise_distributionadd_noise_distributionAddNoiseDistributionAddNoiseDistributionAddNoiseDistributionadd_noise_distribution
See also
mean_imagemean_imageMeanImageMeanImageMeanImagemean_image,
gauss_distributiongauss_distributionGaussDistributionGaussDistributionGaussDistributiongauss_distribution
Module
Foundation