RETRO commands
PROGRAM NAME
venhance - Enhance Image Using the Local Standard Deviation & Mean (K1)
DESCRIPTION
venhance
uses a local transformation based on the mean and variance of the
intensity maps and the intensity of the input image f(x,y) to create a new
image g(x,y) by performing the following transformation at each
pixel location (x,y):
g(x,y) = A(x,y).[f(x,y) -m(x,y)] + m(x,y),
where
A(x,y) = k . M / sigma(x,y) 0 < k < 1
where m(x,y) and sigma(x,y) are the gray-level mean and standard deviation
computed in a neighborhood centered at (x,y), M is the global mean of
f(x,y), and k is a constant in the range indicated above.
REQUIRED ARGUMENTS
- -i
-
type: infile
desc: input image filename
- -o
-
type: outfile
desc: output image filename
OPTIONAL ARGUMENTS
- -w
-
type: integer
desc: window width of local area
default: 3
bounds: 1 < [-w] < 100
- -h
-
type: integer
desc: window height of local area
default: 3
bounds: 1 < [-h] < 100
- -k
-
type: float
desc: specifies scale factor
default: 0.5
bounds: 0 < [-k] < 1
- -v
-
type: float
desc: specifies minimum standard deviation
default: 1
bounds: 0 < [-v] < 2000
EXAMPLES
venhance -i input.image -o output.image -w 5 -h 5 -k .5 -v 2
This command performs image enhancement on input.image and
stores the result in output.image. The size of the window
used is 5 by 5. The tuning factor is .5 and the minimum
allowable standard deviation is 2.
SEE ALSO
Reference: Digital Image Processing (2nd Edition) by Gonzalez and Wintz.
RESTRICTIONS
venhance only operates on byte type images.
REFERENCES
Digital Image Processing (2nd Edition) by Gonzalez and Wintz.
COPYRIGHT
Copyright (C) 1993 - 1997, Khoral Research, Inc. ("KRI") All rights reserved.