ImageDev

Histogram

Contains measurements expressing color or gray level statistical attributes extracted from the intensity image histogram and using the label input image as a mask.

These measurements are based on the intensity input image. Using them with a label or binary intensity image is not relevant.
When applied on a color or multispectral intensity image, these measurements return one value for each intensity channel.

By default, a histogram is automatically computed between the minimum and maximum image intensities with a bin size of 1. These parameters can be customized with the Histogram attributes.

Histogram quantile

A quantile value, associated to a given percentage of observations, is the value of the cumulative distribution at the given percentage.

Such a quantile value is computed by interpolation between the first bin where the cumulated histogram is higher than the percentage of observations and its previous bin.
The cumulated histogram is given at the center of each bin, counting the half population of the current bin. For instance, with a bin size of 1, the cumulated histogram for the bin ]3, 4] is computed adding the total population of the values 0, 1 and 2 to the half population of the value 3. It is assigned to the bin center 3.5.
<b> Figure 1.</b> Histogram quantile interpolation with a bin size of 3
Figure 1. Histogram quantile interpolation with a bin size of 3

With the example above, where the bin size is 3, the 25% quantile value of the histogram is: $$ Q(25) = \lambda \times 7.5 + (1- \lambda) \times 10.5 $$ where : $$ \lambda = \frac{d2}{(d1+d2)} = \frac{h2}{(h1+h2)} $$ In addition to the Histogram attributes which affects the results, some quantile measurements can be user-defined with the Quantile attributes.

Object members

Measurement name DescriptionElement typeIndexingPhysical Information
HistogramMean The average of the intensity histogram values within the object. Floating point [label, channel] INTENSITY
HistogramStandardDeviation The standard deviation of the intensity histogram values within the object. Floating point [label, channel] INTENSITY
HistogramVariance The variance of the intensity histogram values within the object. Floating point [label, channel] INTENSITY
HistogramSkewness The skewness of the intensity histogram within the object, which is a measure of asymmetry.
More information is available in the SkewnessFilter2d algorithm description.
Floating point [label, channel] INTENSITY
HistogramKurtosis The kurtosis indicator of the intensity histogram within the object, which is a measure of the "tailedness".
More information is available in the KurtosisFilter2d algorithm description.
Floating point [label, channel] RATIO
HistogramPeak The main peak of the intensity histogram within the object. Floating point [label, channel] INTENSITY
HistogramQuantile10 The 10% quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
Floating point [label, channel] INTENSITY
HistogramQuantile25 The 25% quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
Floating point [label, channel] INTENSITY
HistogramQuantile50 The 50% quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
Floating point [label, channel] INTENSITY
HistogramQuantile75 The 75% quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
Floating point [label, channel] INTENSITY
HistogramQuantile90 The 90% quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
Floating point [label, channel] INTENSITY
HistogramQuantileR1 The first customizable quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
The corresponding quantile percentage can be user-defined with index 1 of the Quantile attributes.
Floating point [label, channel] INTENSITY
HistogramQuantileR2 The second customizable quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
The corresponding quantile percentage can be user-defined with index 2 of the Quantile attributes.
Floating point [label, channel] INTENSITY
HistogramQuantileR3 The third customizable quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
The corresponding quantile percentage can be user-defined with index 3 of the Quantile attributes.
Floating point [label, channel] INTENSITY
HistogramQuantileR4 The fourth customizable quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
The corresponding quantile percentage can be user-defined with index 4 of the Quantile attributes.
Floating point [label, channel] INTENSITY
HistogramQuantileR5 The fifth customizable quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
The corresponding quantile percentage can be user-defined with index 5 of the Quantile attributes.
Floating point [label, channel] INTENSITY
HistogramQuantileR6 The sixth customizable quantile of the intensity histogram within the object.
More information is available in the Histogram quantile section.
The corresponding quantile percentage can be user-defined with index 6 of the Quantile attributes.
Floating point [label, channel] INTENSITY

Object methods

Method Description
void toDataFrame() Convert the measurement to an IOLink.DataFrame
Method Description
void ToDataFrame() Convert the measurement to an IOLink.DataFrame
Method Description
void to_data_frame() Convert the measurement to an IOLink.DataFrame