Simple NURBS renderer [w/ code]

Screen Shot 2013-12-18 at 11.01.23 AMDon't you just love scouring the web for a piece of simple code, come up short and then just write it yourself? Well that was the case with NURBS for me. These simple curvy lines, why doesn't anyone just dish out a straightforward implementation of them? Well, now you have it. I wrote a simple renderer that reads a DXF file with NURBS (from Rhino3D) using DXFLIB, although the DXF file format is super easy to parse, and renders them to an image with OpenCV.
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Vertex array objects with shaders on OpenGL 2.1 & GLSL 1.2 [w/code]

rect3826Phew. Finally this is working!

I've been confined to OpenGL 2.1 and GLSL 1.2 on the Mac since the Qt OpenGL context will not pick up the core OpenGL profile (a big problem on it's own) and get an OpenGL 3.x and GLSL 1.5... So it's back to old school GL'ing, but anyway some things are working, albeit they have their quirks.
So for all of you battling the OpenGL 2.1 war, here's how I made VAOs work with a very simple shader.
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Extending the hand tracker with snakes and optimizations [w/ code, OpenCV]

I wish to report of a number of tweaks and additions to the hand silhouette tracker I posted a while back. First is the ability for it to "snap" to the object using a simple Active Snake method, another is a more advanced resampling technique (the older tracker always resampled after every frame), and of a number of optimizations to increase the speed (tracker now runs at real-time on a single core).
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FFMPEG video writer - now with animated GIF support [w/ code]

rect3825So animated gifs are awesome if you're writing a software blog. It saves all this time working with YouTube embeddings and stuff, and your "videos" are stored locally. The simplified FFMPEG writer was before unable to output animated GIFs, but I've tweaked it and now it does. It's also a nice piece of code to learn how to FFMPEG in C.
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Curve tracking with a Heap&Hogg's Particle Filters [w/ code, OpenCV]

Screen Shot 2013-03-15 at 6.18.30 PM I wanna share some code for 2D curve tracking with a particle filter, implementing the body of work of Tony Heap and David Hogg. These guys presented a relatively easy to implement method for tracking deformable curves through space and change in form using a Hierarchical Point Distribution Models (HPDM), which is another elegant way to store shape priors. Granted, it is not perfect, but for a simple 2D shape like a hand it works pretty good, and rather fast as well.
Let's dive in then,
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