HI E - Histogram - to determine entropy

(5/22/13)

PURPOSE

Computes entropy of image using a histogram.   Example.

SEE ALSO

HIS [Histogram - image/volume]

USAGE

.OPERATION: HI E [entropy]
[This operation can return one optional register variable:
Variable Example Receives
First [entropy] Entropy

.INPUT FILE: PIC027
[Enter the name of the file containing the image/volume.]

.NUMBER OF BINS: 256
[Set number of bins used in histogram.]

.HISTOGRAM RANGE: <CR>
[Enter range for histogram. Default range is the minimum .... maximum of the file.]

NOTES

  1. For each grey level (bin) compute the frequency f(i) = number of pixels in bin(i) / total pixels in image. Compute Sum of -f(i)*log(f(i)) The sum is the entropy of the image. The following information will be printed out, there is no plot of the histogram:

    FILE RANGE: .........
    HIST. RANGE: .........
    IMAGE PIXELS: HIST. PIXELS:
    NO. OF BINS:
    ENTROPY:

SUBROUTINES

ENTROP

CALLER

UTIL1

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