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HistogramEqualize

HistogramEqualize[img] gives img with enhanced (normalized) contrast in the range {0,255}.

HistogramEqualize[img, {min, max}] gives img with enhanced (normalized) contrast in the range {min, max}.

HistogramEqualize[img, {min, max, dx}] gives img with enhanced (normalized) contrast in the range {min, max} with stepsize dx.

Histogram equalization is a pointwise nonlinear transformation that replaces each pixel by the cumulative histogram value for that pixel.

The option HistogramClippingFactor→c, with the clipping factor c in the range 0≤c≤1, may be used to alter the result returned by HistogramEqualize. The histogram of the original image h is clipped at value c

Max[h] and the residue is uniformly redistributed over all the bins of the histogram h. This alters the shape of the cumulative histogram and therefore the transfer function of the equalization transformation.

The default setting HistogramClippingFactor→None computes histogram equalization using unaltered histogram values.

The argument img may be a list or ImageData expression.

See also User's Guide 3.4.

Modified in Version 2.

Example

This loads the package.

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This loads an example image.

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This performs linearization on the example image.

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This shows linearization with clipping.

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THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.

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