RETRO commands


PROGRAM NAME

vcost - Compute Cost (Surface Arc Length) for Image (K1)

DESCRIPTION

vcost computes the surface arc length from a given pixel location to every other pixel in the image. The surface distance from a particular pixel to the reference pixel location is stored in the corresponding location in the output image. Image pixels are resampled at 1/10 of their spacing using bilinear interpolation for use in forming the surface profile between any two points. This provides an surface distance accurate to around 1% for relatively smooth images. An image with very sharp transitions or other high frequencies will produce less accurate results.

If the mask image is used, then only those pixels that have a non-zero value at the corresponding pixel in the mask will be evaluated for surface distance. All other output pixels are set to -1.

The output is of type float.

REQUIRED ARGUMENTS

-i
type: infile
desc: input image
-o
type: outfile
desc: output image

OPTIONAL ARGUMENTS

-m
type: infile
desc: mask image
default: {none}
-x
type: integer
desc: X coordinate of reference pixel
default: 0
bounds: no range checking
-y
type: integer
desc: Y coordinate of reference pixel
default: 0
bounds: no range checking

EXAMPLES

% vcost -i surface -o dist -x 16 -y 21

SEE ALSO

RESTRICTIONS

lvcost works on all data types.

REFERENCES

COPYRIGHT

Copyright (C) 1993 - 1997, Khoral Research, Inc. ("KRI") All rights reserved.