NAME¶

pgmtexture - calculate textural features on a PGM image

SYNOPSIS¶

pgmtexture

[-d d]

[pgmfile]

DESCRIPTION¶

This program is part of Netpbm(1).

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(1), pamsharpness(1), pamsharpmap(1), pgmedge(1), pgmminkowski(1)

AUTHOR¶

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