Enable JavaScript to interact with content and submit forms on Wolfram websites. Learn how

Legacy Documentation

Digital Image Processing (2000)

This is documentation for an obsolete product.

Current products and services

ScaleSigma

ScaleSigma[img, {mean, var}] returns an exponentially scaled copy of img with the midpoint and sharpness of the transformation controlled by the arguments mean and var, respectively.

ScaleSigma[img, {mean, var}, {min, max}] returns an exponentially scaled copy of img within the limits given by min and max. The midpoint and sharpness of the transformation are controlled by the arguments mean and var, respectively.

ScaleSigma applies the following point transformation to each sample of img:

where x_max, x_min are the desired maximum and minimum values of the output signal and

define the midpoint and sharpness of the transformation.

See also User's Guide 3.4.

New in Version 2.

Example

This loads the package.

In[1]:=

This shows two transformations that differ in the value of variance.

In[2]:=

Out[2]=

Out[2]=

This shows the change in image contrast due to the transformation shown in blue in the previous plot.

In[3]:=

Out[3]=

Out[3]=