NAME

       gpivtools - The PIV tool suite.

DESCRIPTION

       gpivtools  is  a set of command-line driven programs for the so-called Digital Particle Image Velocimetry
       (DPIV). It contains programs for image recording, processing and analysing (resulting into estimators  of
       particle  displacement,  i.e.  PIV  data),  PIV  data  validation  programs and post-processing tools for
       manipulating and calculating (scalar) derivatives of the PIV data.

       Though the command-line driven tools are mainly intended for non-interactive processing, its outputs  may
       directly be visualized in a graphical way with the aid of gnuplot.

       The  parameters  and  options  to  be  used  for  most of the gpivtools are provided by Libgpiv. They are
       subsequently searched in ./gpivrc at local directory, at $HOME/.gpivrc (hidden)  or  at  the  system-wide
       configuration  file  gpiv.conf,  which  is  mostly  found  at  /etc for UNIX-like operating systems. Each
       parameter is described by the process key: GENPAR  (general  parameters),  CAM  (camera  settings),  TRIG
       (trigger  settings),  IMG (image header), IMGPROC (image processing), PIV (piv interrogation), VALID (piv
       data validation) or POST (piv post processing) and the parameter name, separated by a dot  (.),  followed
       by  its  value.  Some  of  the parameters are optional. The parameters may be defined in arbitrary order.
       Blank lines and comment (starting with a pound sign (#) at the first  column)  may  be  included  in  the
       parameter  files.   The  parameters  may  be  overruled by the command line options of each tool. Libgpiv
       provides default parameter values if they are not defined in one of the  configuration  files  or  by  an
       option key at the command line.

       In  case  stdin  and  stdout  is  used,  verbose  output  of the programs is suppressed in order to avoid
       contamination of the output data. If filename is used for overruling stdin and stdout, the parameters are
       written to filename.par. By renaming this file to ./gpivrc or $HOME/.gpivrc, the parameters may  directly
       be  re-used  for identic processing of other images and PIV data. The parameters defined in $HOME/.gpivrc
       and in /etc/gpiv.conf are also used by the Graphic User Interface program gpiv.

       The  programs  understand  different  image  formats:  Portable  Network  Graphics  (filename.png),  HDF5
       (filename.hdf),  raw  binary  data (filename.r) that is accompanied by an ASCII header file (filename.h),
       and LaVision's (tm) uncompressed image format (filename.img). Other formats that use lossless compression
       (TIF, GIF, PGM, BMP) are converted to PNG on the fly. For interrogation  of  double-framed  images  using
       cross-correlation,  the  second image has to be concatenated after the first one, if this has not already
       been done by the recording camera. This might be performed by gpiv_combing.  Image  parameters  are  read
       from the header or from the configuration resources (containing the IMG key).

GPIV-TOOLS COMMANDS

       Here  is  the  complete  list  of available gpivtools programs. See their individual man pages for a more
       extended description.

       gpiv_aint
              Calculates mean image intensity at each interrogation area.  This program uses the  IMG,  PIV  and
              POST parameters.

       gpiv_combing
              Combines  two  images  into  one  image  file  for  cross-correlation.   This program uses the IMG
              parameters.

       gpiv_errvec
              Searches the erroneous vectors in a PIV data file and eventually substitutes them with new values.
              This program uses the PIV and POST parameters.

       gpiv_fi-keyline
              Filters each line that starts with a keyword.  This program does not use the  parameter  resources
              from Libgpiv.

       gpiv_hdf2piv
              Converts  hdf5  PIV  data (extension .hdf) to ASCII data.  This program does not use the parameter
              resources from Libgpiv.

       gpiv_imgproc, gpiv_mktestimg, gpiv_smooth, gpiv_hilo, gpiv_clip, gpiv_fft, gpiv_invfft, gpiv_lowpass,
       gpiv_highpass, gpiv_getbit, gpiv_mktestimg
              (PIV) image processing programs.  These programs use the IMGPROC parameters.

       gpiv_img2gpiv
              Depreciated: use gpiv_combing instead. Converts images into raw data (extension  .r)  format  with
              the  belonging  ASCII header (extension .h) or into hdf format (with extension .hdf). This program
              does not use the parameter resources from Libgpiv.

       gpiv_manipiv, gpiv_fasty, gpiv_flipx, gpiv_flipy, gpiv_revert, gpiv_rot90, gpiv_rot180
              Simple data manipulation tool for PIV data.  These programs use the POST parameters.

       gpiv_peaklck
              Tests PIV data on the so-called peak-locking effect by printing/displaying  an  histogram  of  the
              particle displacements at sub-pixel level.  This program uses the VALID parameters.

       gpiv_piv2gnuplt
              Converts PIV data gnuplot data. Besides this, image interrogation and post-processing programs are
              able  to display their results directly (mostly with the -g option). This program does not use the
              parameter resources from Libgpiv.

       gpiv_piv2grid
              Converts PIV data to grid data for generating contour plots with Plotmtv.  This program  does  not
              use the parameter resources from Libgpiv.

       gpiv_piv2hdf
              Converts  ASCII  PIV  data to hdf5 formatted data (extension .hdf).  This program does not use the
              parameter resources from Libgpiv.

       gpiv_piv2vec
              Adds header to PIV data for a vector plot with Plotmtv.  This program does not use  the  parameter
              resources from Libgpiv.

       gpiv_process-chain
              Processes  a  pipeline of Gpiv-tool command's, forming process a chain from image recording, image
              processing, image interrogation, data validation, data post-processing.  This program does not use
              the parameter resources from Libgpiv.

       gpiv_recimg
              captures images from a IIDC-compliant CCD camera with IEE1394 connection.  This program  uses  the
              IMG parameters.

       gpiv_rr
              Interrogates images in order to obtain displacement estimators of particles for (Digital) Particle
              Image Velocimetry.  This program uses the PIV and VALID parameters.

       gpiv_sca2gri
              Converts  scalar  data  from gpiv to grid data for contour plotting with Plotmtv This program does
              not use the parameter resources from Libgpiv.

       gpiv_scale
              Spatial and time scaling program for PIV data.  This program uses the IMG and POST parameters.

       gpiv_series
              Script for (parallel) processing a series of numbered  files.   This  program  does  not  use  the
              parameter resources from Libgpiv.

       gpiv_suta
              Subtracts  time-avaraged  velocities  (local mean) from the PIV estimators.  This program does not
              use the parameter resources from Libgpiv.

       gpiv_s-avg
              Spatial statistics of PIV data.  This program uses the POST parameters.

       gpiv_t-avg
              Calculates time-avaraged mean and rms from a series of PIV data.  This program does  not  use  the
              parameter resources from Libgpiv.

       gpiv_t-avg-img
              Calculates  time-averaged  values  from  a  series of images at each pixel.  This program uses the
              GENPAR parameters.

       gpiv_t-corr
              Calculates the velocity correlation as function of time (Eulerian correlation) from a  series  PIV
              data sets This program does not use the parameter resources from Libgpiv.

       gpiv_trig
              Triggers a (double Nd_YAGG) laser on a CCD camera.  This program uses the TRIG parameters.

       gpiv_uhisto
              Tests PIV data by printing/displaying an histogram of the horizontal particle displacements.  This
              program uses the VALID parameters.

       gpiv_vhisto
              Tests  PIV  data by printing/displaying an histogram of the vertical particle displacements.  This
              program uses the VALID parameters.

       gpiv_vorstra, gpiv_vorty, gpiv_nstrain, gpiv_sstrain
              Calculates the differential quantities vorticity, shear strain and normal strain  from  PIV  data.
              These programs use the POST parameters.

SEE ALSO

       gpiv, gpiv_control

AUTHOR

       Gerber Van der Graaf

                                                  26 March 2008                                     GPIVTOOLS(1)