Image Enhancement
In practical application, the resulting values in the range (0,1) have to be scaled to the display range of (0, 255).
Histogram equalization is usually implemented via lookup tables.
Histogram equalization can provide only one output image, which may not be satisfactory is some cases.
In a related procedure known as histogram specification, a series of histogram equalization steps is used to obtain an image with a histogram close to a pre-specified histogram.
Then, by specifying different histograms, it is possible to obtain a range of enhanced images.