
vspatial(1)                  Khoros                   vspatial(1)

PROGRAM
     vspatial - Spatial Feature Operators

SYNTAX
     vspatial

     -i             input image filename

     -o             output image filename

     [-w]           window width argument

     [-h]           window height argument

     [-m]           choose Mean Spatial Operator

     [-v]           choose Variance Spatial Operator

     [-c]           choose Contrast Spatial Operator

     [-s]           choose Ang 2nd Moment Spatial Operator

     [-e]           choose Entropy Spatial Operator

     [-d]           choose Dispersion Spatial Operator

     [-V]           Gives the version for vspatial

     [-U]           Gives the usage for vspatial

     [-P]           Prompts for command line options

     [-A [file1]]   Creates the answer file called vspatial.ans
                    or file1

     [-a [file1]]   Uses vspatial.ans or file1 as the answer file

DESCRIPTION
     vspatial performs a spatial feature extraction on an image
     using a selected statistical operation.  The statistical
     operation is computed, using overlapping windows, over the
     entire image.  The center pixel is updated in each window
     based on the calculated statistics of that window.

     The input image, which must be of data storage type BYTE,
     corresponds to the -i argument.  The output image, which
     corresponds to the -o argument, is stored as data type
     FLOAT.  The output image may be a multiband image depending
     on how many spatial operators were selected.  The resulting
     image will have a border of pixels of value 0, since the
     window operation does not calculate values for border pix-
     els.

     The width and height of the window is specified by the -w
     and -h window width and height arguments.  The width and
     height arguments cannot be an even number.  The window
     dimensions must be odd (ie. 3x3, 5x5, 7x7, etc.), since the
     center pixel is replaced with the computed value of the win-
     dow data.  The default window size is 3x3.

     Each pixel in the image is updated with a computed value
     except the border pixels.  A 3x3 window will result in a
     border of one pixel, a 5x5 window will result in a border of
     two pixels, etc.

     There are six statistical operations that may be selected.
     Any combination of the statistical operations may be
     selected by toggling the desired argument on (ie. argument
     followed by a 1).  The default for each argument is
     unselected (ie. argument followed by a 0), except -m (mean),
     which is selected.  The six possible statistical operations
     and their arguments are:

       -m  --  calculates the mean of the image.
       -v  --  calculates the variance of the image.
       -c  --  calculates the contrast of the image.
       -s  --  calculates the angular second moment of the image.
       -e  --  calculates the entropy of the image.
       -d  --  calculates the dispersion of the image.

     The resulting feature vector may contain from one to six
     bands of data, depending upon the number of arguments
     selected.

     All input images must be of data storage type BYTE.

     All output images are of data storage type FLOAT.

REQUIRED ARGUMENTS
     -i     type: infile
            desc: input image filename

     -o     type: outfile
            desc: output image filename

OPTIONAL ARGUMENTS
     -w     type: integer
            desc: window width argument
            default: 3
            bounds: 1 < [-w] < 64

     -h     type: integer
            desc: window height argument
            default: 3
            bounds: 1 < [-h] < 64

     -m     type: boolean
            desc: choose Mean Spatial Operator
            default: true

     -v     type: boolean
            desc: choose Variance Spatial Operator
            default: false

     -c     type: boolean
            desc: choose Contrast Spatial Operator
            default: false

     -s     type: boolean
            desc: choose Ang 2nd Moment Spatial Operator
            default: false

     -e     type: boolean
            desc: choose Entropy Spatial Operator
            default: false

     -d     type: boolean
            desc: choose Dispersion Spatial Operator
            default: false

EXAMPLES
     vspatial -i input_image.xv -w 5 -h 5 -m 0 -v 1 -e 1 -o
     output_image

     the input image must of type BYTE; the selected width and
     height of the window is 5 x 5, which will result in a border
     width of two pixels in the output image.  The mean spatial
     operator is unselected (default is selected), and the vari-
     ance and entropy operations are selected, which will result
     in an output image (feature vector) of 2 bands, based on the
     operations selected.

SEE ALSO
     intro(1), verror(3), vgparms(3), vutils(3), lvspatial(3)

RESTRICTIONS
     All input images must be of data storage type BYTE.

     All output images are of data storage type FLOAT.

COPYRIGHT
     Copyright 1991, University of New Mexico.  All rights
     reserved.

Khoros                    Release: 1.0                          1

