The H_EQ_INT function interactively histogram-equalizes the color tables of an image or a region of the display. By moving the cursor across the screen, the amount of histogram-equalization can be varied.
Either the image parameter or a region of the display marked by the user is used to obtain a pixel-distribution histogram. The cumulative integral is taken and scaled and the result is applied to the current color tables.
This routine is written in the IDL language. Its source code can be found in the file
subdirectory of the IDL distribution.
A window is created and the histogram equalization function is plotted. A linear ramp is overplotted. Move the cursor from left to right to vary the amount of histogram equalization applied to the color tables from 0 to 100%. Press the right mouse button to exit.
A two-dimensional byte array representing the image whose histogram is to be used in determining the new color tables. If this value is omitted, the user is prompted to mark the diagonal corners of a region of the display. If Image is specified, it is assumed that the image is loaded into the current IDL window. Image must be scaled the same way as the image loaded to the display.