WB_THRESHOLD - thresholds an image on a given grey
NAME
WB_threshold
WB_threshold
-l[level]
|
-t[level]
input-file
[
output-file
]
WB_threshold
performs either a global thresholding of an image or a local thresholding.
Global thresholding means that al pixels with a grey value less than the
threshold value will be changed into black pixels and all others into white.
Local thresholding turns black those pixels who have a value which is less
than the local average around that pixel.
The
input-file
should be a
.pgm
image file. If an
output-file
is specified this file will be used to store the resulting image.
Otherwise the result is written to the
input-file.
- -l[local threshold level]
- Perform a local thresholding. The local threshold level will
be added to the local average. The default local threshold level is 10.
- -t[global threshold level]
- Perform a global thresholding. All pixels with values greater than the
global threshold level will be changed into white pixels all others will
become black.
The default value of the global threshold level is 128.
skel_dyer(1)
06-May-97. Automatically converted by man2html,
written by G.Matas (g.matas@ee.surrey.ac.uk)