NAME

       gpiv - Analyzes images obtained from a fluid flow by Particle Image Velocimetry.

SYNOPSIS

       gpiv  [-?  |  --help]  [--usage]  [--console_bins BINS] [--console_tooltips] [--console_view_gpivbuttons]
       [--console_view_tabulator]    [--display_background      INT]     [--display_intregs]     [--display_piv]
       [--display_stretch]   [--display_scalar    INT]  [--display_vectorscale  SCALE]  [--display_view_menubar]
       [--display_view_rulers] [--display_zoomscale SCALE] [--hdf]  [--img_fmt]  [--mpi_nodes]  [-p  |  --print]
       [--process_imgproc]   [--process_piv]   [--process_gradient]   [--process_resstatst]   [--process_errvec]
       [--process_peaklock]  [--process_average]  [--process_scale]  [--process_substract]   [--process_vorstra]
       [IMAGE1, IMAGE2, ...]

DESCRIPTION

       Gpiv  is  a  Graphic User Interface program for recording and analyzing images obtained from a fluid flow
       that has been seeded with tracer particles by the so-called Particle Image Velocimetry  (PIV)  technique.
       It  allows  to  have  a  quick  overview  of  the  process  settings, easily changing them, executing the
       processes, visualizing and optimizing their results in an interactive way.  The  processes  that  may  be
       performed  are  image  recording,  interrogation  (resulting  into  PIV estimators), validation and post-
       processing of the PIV estimators.

       The settings for the PIV processes are subsequently searched in ~/.gpivrc or in gpiv.conf (system  wide),
       which is provided by libgpiv.

       For recording images, gpiv recognizes (CCD) cameras that are IIDC-compliant and connected to the Computer
       with the IEEE1394 or Firewire protocol.

       In  case  gpiv  will  trigger a camera and lasers, it uses a kernel module gpivtrig_rtl from the gpivtrig
       package that depends on the Real Time Application Interface (RTAI) and RealTimeLinux. Trigger pulses  are
       send  to  the  parallel  port  of  the  Computer (/dev/lpt0 or /dev/lpt1; see the configure script of the
       gpivtrig package) at bins #1 (camera), #2 and #3 (first and second laser respectively). The  program  may
       be  started  directly if all modules have been loaded or by the gpiv_control script, also included in the
       gpivtrig package, which takes care of the loading and unloading of the needed kernel modules.  Currently,
       the trigger system is tested with RTAI-3.1 and the linux kernel-2.4.27.

       The  parameters  and options to be used for gpiv are obtained from ~/.gnome2/gpiv or default settings are
       to be used if absent. The  settings  may  be  changed  or  updated  by  menu->settings->preferences.  The
       parameters  of  gpiv  (not  the  PIV  process  settings) may be overruled by the command line options, as
       explained below.

       When gpiv is used on a (Beowulf, distributed memory) cluster, the MPI-parallelised program  gpiv_rr  from
       the  gpivtools package is invoked using mpirun. The gpiv program, however, is launched in the normal way,
       without invoking mpirun.

Options

       -? | --help
              On-line help. Besides the options of gpiv it also shows the additional GNOME, GTK  and  GNOME  GUI
              options.

       --usage
              Display a brief usage message.

       --console_bins BINS
              Number  of bins for histograms of estimators at sub-pixel level, performed by the peaklock process
              and of the median residues, performed by the errvec process.

       -t | --console_tooltips
              Show tooltips.

       --console_view_gpivbuttons
              View the gpiv buttons of the application.

       --console_view_tabulator
              View the tabulator of the application containing all PIV process settings.

       --display_background INT
              Displaying of background: INT = 0: darkblue INT = 1: black INT = 2: first frame of image INT =  3:
              second frame of image

       --display_intregs
              Enables displaying of interrogation regions.

       --display_piv
              Displaying of PIV data.

       --display_stretch
              Enables automatic stretching of the display when zooming.

       --display_scalar INT
              Display  derived  quantities from PIV data: INT = 0: none INT = 1: vorticity INT = 2: shear strain
              INT = 3: normal strain

       --display_view_menubar
              Enables displaying of the menubar.

       --display_view_rulers
              Enables displaying of the ruler.

       --display_vectorscale SCALE
              Display vector with index: SCALE = 0: magnification factor = 1, SCALE = 1: magnification factor  =
              2,  SCALE  =  2:  magnification  factor  =  4,  SCALE  =  3:  magnification factor = 8, SCALE = 4:
              magnification factor = 16, SCALE = 5: magnification factor = 32, SCALE = 3: magnification factor =
              64, SCALE = 4: magnification factor = 128, SCALE = 5: magnification factor = 256.

       -z | --display_zoomscale SCALE
              Display zoom with index: SCALE = 0: magnification factor = 0.5, SCALE = 1: magnification factor  =
              0.83,  SCALE  =  2:  magnification factor = 1.0, SCALE = 3: magnification factor = 1.3, SCALE = 4:
              magnification factor = 1.6, SCALE = 5: magnification factor = 2.0.

       --hdf  Save data in HDF5 format with .gpi extension.

       --img_fmt INT
              store (modified) image data and header in: INT = 0: PNG format, INT = 1: raw format, INT = 2: HDF5
              format, included with the resulting PIV and post-processing data with .gpi extension.

       --mpi_nodes INT
              To define the number of nodes when used on a cluster. Used by mpirun -np INT.

       -p | --print
              Print process parameter settings to stdout.

       --process_imgproc
              Includes image processing in the chain-process.

       --process_piv
              Includes piv interrogation in the chain-process.

       --process_gradient
              Includes testing on the displacement gradient within interrogation area in the chain-process.

       --process_resstatst
              Includes calculation of statistics of displacement residuals in the chain-process.

       --process_errvec
              Includes validation on PIV data in the chain-process.

       --process_peaklock
              Includes peak lock in the chain- process.

       --process_average
              Includes calculation of the whole field average PIV displacements in the chain-process.

       --process_scale
              Includes scaling in the chain-process.

       --process_subtract
              Includes substracting of the whole field average PIV displacements in the chain-process.

       --process_vorstra
              Includes calculation of vorticity in the chain-process.

       IMAGE1, IMAGE2, ...
              Loads IMAGE1, IMAGE2, ... from a file or from an URI using the Gnome  Virtual  File  System.   The
              maximum allowed image dimensions and quantity to be loaded are defined by the program as described
              in gpiv_gui.h or by the 'configure' script during the building of gpiv.

SEE ALSO

       On-line  documentation  at http://gpiv.sourceforge.net/gpiv_doc/index.html or from the help-menu of gpiv,
       gpiv_control(1) and gpivtools(1).

AUTHOR

       Gerber Van der Graaf

                                                14 December 2007                                         GPIV(1)