Gpiv Code
Status: Beta
Brought to you by:
gerber_graaf
GPIV is a graphic user interface for analyzing images obtained from a fluid flow that has been seeded with tracer particles by the so-called Particle Image Velocimetry technique. It is meant to have a quick overview of the parameters of all piv processes, easily changing them, running the processes and visualizing their results in an interactive way. It uses LIBGPIV, which contains the main routines for data in-and output, processing etc. The software is written in ANSI-C under the LINUX operating system by using the GTK/GNOME libraries. GPIV is Free Software licensed under the GNU Public license terms. See the COPYING file for the license. The main web page can be found at: http://gpiv.sourceforge.net/ Compilation and installation ============================ The General instructions of compilation and installation can be found in INSTALL. There are some additional configuration options for this program, as well. These are: --enable-cam --enable-trig --enable-rta=RTA_DIR --enable-k=K_DIR --enable-img-width=WIDTH --enable-img-height=HEIGHT --enable-debug An explanation of these options is printed with ./configure --help. Features ========= General ======== - Data storage in ASCII format or HDF version 5 format. - Loading of images with with file-open menu, "open" button or with "drag and drop" from the gnome file-manager "nautilus" into the buffer list. - Quick execution of all enabled process on all selected buffers. Display ======== - Visualization of interrogation area contours and highlighting them when pointing to it. - Displays pointer position and belonging estimated values. Image recording =============== - Sending trigger pulses over the parallel port by using Real Time Linux and RTAI - Obtaining images from a IEEE1394 (Firewire) IIDC_Compliant CCD camera Image info =========== - shows image name, dimensions and type of correlation (cross or auto). - defining of spatial and time scales, position of image within the experiment. - Adding and updating header information (date of creation, project, comment etc). Image evaluation ================= - Interrogation at the entire image or at a defined region within the image frames, resulting into a displacement field on a rectangular grid. - Interrogation at a single arbitrary point, along a vertical or horizontal line. - Re-interrogation of a single area with, different parameters. - Dragging a single interrogation area from the rectangular grid. - Arbitrary interrogation area sizes. - Global pre-shifting. - Local pre-shifting or zero offsetting of the interrogation areas. - Forward and central interrogation scheme. - Adaptive interrogation area sizes to obtain high resolution and dynamic range. - Different interpolation schemes for sub-pixel estimation. - Cross and auto correlation. - Defining the order of correlation peak to be used as estimator. - Visualization of interrogation area's and correlation function. Data validation =========== - Manually enabling and disabling of PIV estimators interactively. - Checking on peak-locking effects. - Validation on outliers by snr value or median test. Post-processing =============== - apply time and spatial scaling - calculate statistics and subtraction of mean values from estimators - calculation of vorticity and strain.