HOPT-Histogram optimization of an image

Description:

Performs a histogram equalisation on an image in an attempt to enhance the contrast. See, for example, Gonzalez and Wintz, 'Digital Image Processing', Addison-Wesley).

Parameters:

IMAGE

Name of image to be equalised.

MINVAL

Minimum data value to be used.

MAXVAL

Maximum data value to be used.

EQUALISE

Generate equalised output data?

OUTPUT

Name of resulting image.

See also:

KAPPA: LAPLACE, LUTABLE, SHADOW, THRESH.

Source comments:

 H O P T

 Performs a histogram equalisation on an image in an attempt
 to enhance the contrast.  See, for example, Gonzalez and
 Wintz, 'Digital Image Processing', Addison-Wesley).

 Command parameters -

 IMAGE  The name of the structure containing the image.

 MINVAL The minimum value to be used in generating the
        histogram.

 MAXVAL The maximum value to be used in generating the
        histogram.

 OUTPUT The name of the result of the operation.  This can
        be the same as for IMAGE.  If not, a new structure
        is created, with everything but the data a direct
        copy of the input.

 Command keywords -

 EQUALISE  Actually perform an equalisation.  If this is
           no (most likely if EQUALISE is not set) then
           all that happens is that the distribution
           histogram is generated and displayed.

 User variables -

 SOFT    (Character) The device/type to be used for terminal
         graphics.

                                  KS / CIT 27th Jan 1983