General
- Data storage in ASCII or HDF format.
- Integration within the Gnome desktop:
Loading of images with "drag and drop" from the gnome
file-manager Nautilus into the buffer list.
Inclusion of Gpiv launcher into menu and taskbar (pre-compiled package).
- Pipeline execution of enabled processes.
- Batch processing on selected buffers.
- Minimizing the console interface when desired by undisplaying the
parameter settings tabulator and detaching the buffer list.
- Quick execution by means of toolbar buttons.
- On-line help from info line, tooltips and manual.
Display
- Visualization of the image(pair).
- Shows interrogation area contours that will be highlighted when
pointing to them.
- Displaying of pointer position and belonging estimated values.
- In and out zooming of displayed features.
- Defining vector length.
- Showing of vector colors related to specified criterium
(validation threshold, correlation peak number, enabled/disabled)
- Displaying of derived scalar quantities (vorticity and strain) as
background.
Record
- Triggering of lasers and camera by means of RTAI over the parallel port of the Computer.
- Recording images from a IIDC-compliant (CCD) camera that is
connected to the Computer by the IEEE1394 (Firewire, I-Link) protocol. A list
of such cameras can be found
here.
Image
- Displaying 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).
Interrogation
- Interrogation by means of image-deformation techniques, using 5th
order B-spline interpolation.
- Adaptive interrogation area sizes.
- Grid refinement by using bi-linear interpolation with shifted knots.
- Validation after each iterative interrogation step.
- Global pre-shifting.
- Local pre-shifting or zero offsetting of the interrogation
areas with forward or central difference scheme at integer number of pixels.
- Three interpolation schemes for sub-pixel estimation.
- Cross and auto correlation.
- Choice of correlation peak for estimating particle displacements.
- Arbitrary interrogation area dimensions.
- Interrogation at the entire image or at an Area Of Interest,
resulting into a displacement field on a rectangular grid.
- Interrogation at a single arbitrary point, along a vertical or
horizontal line by pointing in the image frame.
- Re-interrogation of a single area with different
parameters.
- Dragging a single interrogation area from the rectangular
grid.
- Visualization of interrogation area's and correlation
function.
Data validation
- Enabling and disabling of PIV estimators manually.
- Graphical representation of histogram containing displacements at
sub-pixel level to check on peak-locking effects.
- Graphical representation of histogram of residuals, calculation of
threshold for acceptance of PIV estimators.
- Validation on outliers by SNR value or median test from normalized residus.
Post-processing
- Time and spatial scaling.
- Calculation of statistics and subtraction of the mean value from
the estimators.
- Calculation of vorticity and strain.
Gerbervan der Graaf
email: gerber_graaf AT users DOT sourceforge DOT net
Last modified: Mon Nov 17 09:31:44 CET 2008