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.TH "Pgmtexture User Manual" 0 "22 Aug 1991" "netpbm documentation"

.SH NAME

pgmtexture - calculate textural features on a PGM image

.UN synopsis
.SH SYNOPSIS

\fBpgmtexture\fP

[\fB-d\fP \fId\fP]

[\fIpgmfile\fP]

.UN description
.SH DESCRIPTION
.PP
This program is part of
.BR Netpbm (1)
.
.PP
\fBpgmtexture\fP 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 \fId\fP (default = 1).
.PP
Textural features include:


.IP \(bu
Angular Second Moment
.IP \(bu
Contrast
.IP \(bu
Correlation
.IP \(bu
Variance
.IP \(bu
Inverse Difference Moment
.IP \(bu
Sum Average
.IP \(bu
Sum Variance
.IP \(bu
Sum Entropy
.IP \(bu
Entropy
.IP \(bu
Difference Variance
.IP \(bu
Difference Entropy
.IP \(bu
Information Measures of Correlation
.IP \(bu
Maximal Correlation Coefficient

     
.PP
Algorithm taken from: \fIHaralick, R.M., K. Shanmugam, and
I. Dinstein. 1973. Textural features for image classification.
\fIIEEE Transactions on Systems, Man, and Cybertinetics,\fP
SMC-3(6):610-621.\fP
     
.UN limitations
.SH LIMITATIONS
.PP
The method for finding the Maximal Correlation Coefficient, which requires
finding the second largest eigenvalue of a matrix Q, does not always converge.

.UN seealso
.SH SEE ALSO
.BR pgm (5)
,
.BR pamsharpness (1)
,
.BR pamsharpmap (1)
,
.BR pgmedge (1)
,
.BR pgmminkowski (1)


.UN author
.SH AUTHOR

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