Main Features:
* userfriendly and GUI based PIV tool
* multi-pass, multi-grid window deformation technique
* import bmp/ tiff/ jpeg image pairs/ series
* multiple image sequencing styles
* individual image masking and region of interest
* image pre-processing
* two different sub-pixel estimators
* multiple vector validation methods
* magnitude/ vorticity/ divergence/ shear / ...
* data smoothing, vector field highpass
* multiple colormaps
* streamlines
* extensive data extraction tools
* statistics
* synthetic PIV image generator
* Many data export features
* main features accessible via comand line scripting

Thursday, October 16, 2014

PIVlab short paper out

Thielicke, W. and Stamhuis, E.J. 2014. PIVlab – Towards User-friendly, Affordable and Accurate Digital Particle Image Velocimetry in MATLAB. Journal of Open Research Software 2(1):e30, DOI: http://dx.doi.org/10.5334/jors.bl

pdf: http://openresearchsoftware.metajnl.com/article/download/jors.bl/84

Saturday, October 11, 2014

PhD thesis finished


Received a couple of printed books of my dissertation today. Yaaaay!

I'll add a link to the PIVlab chapter asap when the University of Groningen has uploaded the pdf to their repository.

Monday, June 30, 2014

PIVlab update 1.35

Almost two years since the last update... Here's the list of changes:
  • Instructions on how to cite PIVlab in your publication (in the menu: 'Referencing / Help'). This will be updated again as soon as my papers got accepted.
  • Streamlines now run through user selected coordinates
  • Parameter name included in color bar
  • Region of interest can additionally be selected by entering coordinates
  • 'Wiener2' adaptive denoise filter in image pre-processing
  • Pdf file export
  • Updated link to tutorial
  • Matlab version check (I don't have access to Matlab 7.1 anymore, therefore the minimal supported version now is Matlab 7.10.0 (R2010a)
  • Several small bug-fixes / improvements
The download link: PIVlab @ Matlab FEX

Have fun!
--William

Wednesday, February 19, 2014

I updated the tutorial for PIVlab.


The next release of PIVlab is in progress. It will have some additional features and some bug fixes.

Tuesday, September 25, 2012

PIVlab update 1.32

Changes

piv_FFTmulti.m:

  • Updated analysis progress report
  • During analysis, the PIVlab main window is not forced to get the focus
  • Corrected bug: Case sensitivity for "smoothn" in newer Matlab versions (thanks to Eileen)

PIVlab_commandline:

  • Corrected bug were u and v were confused in data validation

PIVlab_GUI.m:

  • Clear all masks: Confirmation dialogue
  • Apply current mask to a custom selection of frames
  • Export data to binary VTK file for Paraview
  • Exported files now respect the "subtract flow" values
  • Quit PIVlab confirmation dialogue
  • Calculate mean vectors of a custom selection of frames
  • Corrected bug during export with filenames containing a point (".", thanks to Orest)
  • Corrected bug: Case sensitivity for "smoothn" in newer Matlab versions
  • Corrected bug when using colored calibration images
Download PIVlab 1.32 now:
PIVlab @ Matlab File Exchange

Friday, March 30, 2012

PIVlab 1.31

New / modified features in PIVlab v1.31:
  • Included units (e.g. "m", "m/s", "1/s" or "px", "px/frame", "1/frame" etc.) wherever possible
  • Export image as *.eps
  • Modified "Export to Matlab Workspace" (all data availbable now)
  • Colorbar position adjustable
  • Image import: Browse folders button
  • Image import: Regular expression filter
  • Zoom and pan buttons
Now available for download: http://www.mathworks.com/matlabcentral/fileexchange/27659

Friday, January 27, 2012

PIVlab 1.3

PIVlab version 1.3 is out!


New features:
  • Modify vector color
  • Apply to all frames in area / line extractions
  • Post-processing from commandline
  • Load user-generated masks
  • Plot only every nth vector
  •  Line Integral Convolution (LIC) feature from the Matlab Vector Field Visualization toolkit (http://sccn.ucsd.edu/~nima/)
  • Add display update between individual passes
  • Image preview during image selection
  • Modified interrogation area preview
  • Several small improvements

 Screenshots of some of the changes:
Modify plot appearance

Area extractions (do extractions for all frames)

Image preview

Preview of the interrogation area

Line Integral Convolution

Line Integral Convolution

Poly line extractions (do extractions for all frames)

Thursday, November 24, 2011

A quick note on processing speed

Soon, I will need to analyze a large dataset (441.000 image pairs), so I did some tests to speed up the data processing. When using a QuadCore computer (actually 8 virtual cores in this case), up to eight Matlab instances can run in parallel to increase speed. Running more instances will result in a decrease in speed.
A similar effect is also possible with a DualCore computer. Running two Matlab instances in parallel increases the speed by almost 100%.
If you also need to save time, you might try to split your data and run as many Matlab instances as there are (virtual) CPU cores on your computer. Starting the PIV analysis from the commandline (see example in PIVlab_commandline.m), and starting Matlab with the "-nodesktop" command will additionally increase speed.
Processing time for the analysis of one large image pair with multiple passes on different systems

Thursday, July 14, 2011

Thursday, July 7, 2011

PIVlab 1.2: Window deformation & streamlines

The new PIVlab release supports an advanced correlation technique (I want to thank Kyle Lynch for the discussion about this). Using a multipass window deformation technique, significantly reduces noise in the data. The maximal vector resolution can also be increased and peak-locking is reduced a lot. PIV images that have a low quality can now be processed with higher precision (see the video at the bottom).
Additionally, it is possible to draw some streamlines and streamline rakes, this is useful for adding some qualitative information to the analyses.
The image export procedure has also been improved, it is possible to export the displayed result at any desired resolution (only limited by the RAM on your computer).

Standard direct cross-correlation (DCC) analysis using a 14*14px interrogation area with 50% overlap:

Multipass, window-deformation using a 6*6px interrogation area with 50% overlap in the final pass:

Streamlines:
Processing low quality images:
video

The new code will be uploaded to MATLAB Central soon, I just have to do some final tests.

Monday, April 11, 2011

PIVlab 1.13 released

  • Changed figure and all UI element units from pixels to points. This hopefully solves some problems with displaying the GUI.
  • Statistics toolbox no longer required to run PIVlab (implemented NaN Suite by J. Gläscher into PIVlab)
Download PIVlab 1.13 @ Matlab Central

Thursday, November 18, 2010

PIVlab 1.1 released

PIVlab v 1.1, added features / improvements:

  • better smoothing algorithm (smoothn.m) if supported (otherwise gaussian kernel is used)
  • removed several known bugs/ pitfalls
  • added a feature to extract tangential velocity along a series of circles with increasing radius (useful to calculate vortex circulation)
  • added a feature to extract circulation via integrating the vorticity over area for a series of an increasing area
  • added a feature to calculate the weighted centroid of derived parameters
  • improvements in the particle image generation algorithm
  • added several flow simulations (including Hamel-Oseen vortices and vortex pairs)
  • vector width is user selectable
Download PIVlab @ Matlab Central

PIVlab analysis

Synthetic PIV images were created using PIVlab's built-in image generator:

Thursday, May 20, 2010

PIVlab 1.0 released

PIVlab is now available for download (see right hand side of this blog for the link).
Here is a recent video showing a standard PIV analysis: