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


       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, ...]


       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

       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.


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

              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.

              View the gpiv buttons of the application.

              View the tabulator of the application containing all PIV process

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

              Enables displaying of interrogation regions.

              Displaying of PIV data.

              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

              Enables displaying of the menubar.

              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  =

       --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.

              Includes image processing in the chain-process.

              Includes piv interrogation in the chain-process.

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

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

              Includes validation on PIV data in the chain-process.

              Includes peak lock in the chain- process.

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

              Includes scaling in the chain-process.

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

              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.


       On-line                        documentation                         at  or  from the help-menu
       of gpiv, gpiv_control(1) and gpivtools(1).


       Gerber Van der Graaf

                               14 December 2007