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The Stretch Function

==================== JIMSAIP can store pixel values up to 65535. Many images have pixels values that fall well below that value and it is often advantageous to 'stretch' the image data to take advantage of a larger dynamic range. You might want to do this especially before applying such functions as Exponent, Logarithm, Histogram Equalization, or Deconvolution.

You can determine the range for your images using the View-Histogram function.

Stretch does the same thing as selecting BLACK and WHITE levels, except the operation is on the stored data and not just the video representation. As such it is permanent (if saved). You are asked to supply a BLACK level and a WHITE level. All pixel values less than or equal to the BLACK level are assigned a value of zero, and all pixel levels greater than or equal to the WHITE level are assigned a value of 65535. Pixel values in between the extremes are linearly interpolated. The results are stored in the B buffer (with the A buffer unchanged).

Black and White Input Box