SYNOPSIS
pgmtexture

[-d d]

[pgmfile]


DESCRIPTION
This program is part of Netpbm.

pgmtexture reads a PGM image as input and calculates textural features
based on spatial dependence matrices at 0, 45, 90, and 135 degrees for
a distance d (default = 1).

Textural features include:



? Angular Second Moment

? Contrast

? Correlation

? Variance

? Inverse Difference Moment

? Sum Average

? Sum Variance

? Sum Entropy

? Entropy

? Difference Variance

? Difference Entropy

? Information Measures of Correlation

? Maximal Correlation Coefficient



Algorithm taken from: Haralick, R.M., K. Shanmugam, and I. Dinstein.
1973. Textural features for image classification. IEEE Transactions
on Systems, Man, and Cybertinetics, SMC-3(6):610-621.


LIMITATIONS
The program can run incredibly slow for large images (larger than 64 x
64) and command line options are limited. The method for finding the
Maximal Correlation Coefficient, which requires finding the second
largest eigenvalue of a matrix Q, does not always converge.


SEE ALSO
pgm, pamsharpness, pamsharpmap, pgmedge, pgmminkowski


AUTHOR
Copyright (C) 1991 by Texas Agricultural Experiment Station, employer
for hire of James Darrell McCauley.



netpbm documentation 22 Aug 1991 Pgmtexture User Manual(0)