Friday, November 28, 2008

Random Number Generator

During my tests I often needed to produce some random numbers. Sometimes, when the occasion does not justify more worries, I used a very useful site developed by Mads Haahr of the School of Computer Science and Statistics at Trinity College, Dublin in Ireland. The RANDOM.ORG produces true random numbers and has been a useful help. It seems that it is now turning into a commercial site but I hope it remains free, at least for the basic features.

Saturday, November 15, 2008

Feature vector distances between similar shapes

While writing the PhD dissertation I need to depict some data I gathered during my research. One example regards the distances measured between spherical harmonics feature vectors of similar 3D shapes. In the last couple of days I've been working on this, producing results such as the depicted below.


Distances between SHA feature vectors for a set of similar shapes.


Chart depicting the distances of top 5 similar shapes on ESB collection

Thursday, November 06, 2008

Prototypes working on Linux

Although developed aiming a cross-platform solution, the prototypes of my PhD research only have been compiled in Windows. Until now. Moved by the need of having my prototypes running on a Linux system, I dedicated a few hours to creating a makefile and making some slight changes in the code in order to compile the prototypes in Linux. It worked fine! Now I have my prototypes running in both Windows and Linux!

Tuesday, November 04, 2008

Spherical Harmonics Visual Representation

Although I had developed most of the code in the last year, just today I assembled all together in order to create a prototype that produces visual representations of spherical harmonics (SHA) signatures. The SHaVisRep prototype receives as input the binary signature created by the the executable for computing SHA representations provided by Kazhdan and produce a visual representation for this descriptor. This visual representation can be a 3D column chart or a 2D line chart in VRML or BMP format, respectively. The Win32 version of the prototype is avaliable for download [ZIP 110KB].

Ant 3D model
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Shperical harmonics of ant 3D model, represented as a 3D column chart
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Shperical harmonics of ant 3D model, represented as a 2D line chart