NAME
gpiv_scale - Scaling of PIV data.
SYNOPSIS
gpiv_scale [-h | --help] [-p | --print] [-s M |-S M] [-t dT |-T dT] [-v
| --version] [-zp x0 y0] [-zv x0 y0] [filename] < stdin > stdout
DESCRIPTION
gpiv_scale applies the image magnification and the time between
successive recordings to the PIV estimators. This results that particle
displacements [px] are modified to velocities [m/s] and their positions
from [px] to [m]. A physical reference for the positions of the PIV
data can be applied by means of the image zero-offset option.
If filename is used, the parameters and options to be used for
gpiv_scale are subsequently read from the image header (filename.h in
case of raw binary images) or from the configuration resources
(containing the IMG and POST keys). The parameters may be overruled by
the command line options, as explained below.
Options
-h | --help
On-line help.
-p | --print
Prints parameters, command line options and input and output
filenames to stdout. The output is identic of filename.par, in
case -f is used.
-s M spatial scaling with magnification factor M [m/px]
-S M Inverse spatial scaling with magnification factor M [m/px];
returns scaled data to their original magnitudes.
-v | --version
Prints version information on standard output, then exits
successfully.
-t dT Translates particle displacements into velocities by devising
them with the time between subsequent recordings dT [s].
-T dT Inverse time scaling. Returns velocities into displacements [px]
[-z x0 y0]
Relates the positions of the observations of
velocities/displacements to a physical location in the
experiment by image zero offsetting. x0 y0 denote the physical
position of pixel (0,0) in the image.
filename
Input PIV file. Overrides stdin and stdout. The output will be
written to filename.sc.piv. Parameters are stored in
filename.par and may be used for future use by including them in
./gpivrc.
SEE ALSO
gpivtools
NOTES
AUTHOR
Gerber Van der Graaf
BUGS
The program has been tested for PIV data. So far, no bugs have been
found.
8 November 2006