
vrshift(1)                   Khoros                    vrshift(1)

PROGRAM
     vrshift - Do a right shift pixel by pixel on an image.

SYNTAX
     vrshift

     -i             input image

     -o             resulting output image

     -s             number of bit positions to shift

     [-m]           right shift operation masking image

     [-V]           Gives the version for vrshift

     [-U]           Gives the usage for vrshift

     [-P]           Prompts for command line options

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

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

DESCRIPTION
     vrshift performs a right shift on image data pixel by pixel
     using an operation gating image.  The shift could be an
     arithmetic shift or a logical shift (0's into the most sig-
     nificant bit) depending on which machine it is executed on.
     In effect each pixel is divided by two and the remainder
     discarded.

     The optional mask image must be of the same size and data
     type as the input image, and is used to gate the operation.
     A non-zero mask pixel enables the output pixel to contain
     the shifted value.  A zero mask pixel just transfers the
     value of the corresponding pixel in the input image to the
     output pixel without shifting it.

REQUIRED ARGUMENTS
     -i     type: infile
            desc: input image

     -o     type: outfile
            desc: resulting output image

     -s     type: integer
            desc: number of bit positions to shift

OPTIONAL ARGUMENTS
     -m     type: infile
            desc: right shift operation masking image

EXAMPLES
     vrshift -i input.image -o output.image -s 1

     This command takes each pixel in input.image and shifts it
     right one bit position.  The position of the pixel in the
     image does not change, only the value of each pixel changes.

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

RESTRICTIONS
     vrshift will not operate on:
          Transforms, Float, Complex, and Bit
     data storage types.

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

Khoros                    Release: 1.0                          1

