More Than Technical

Hi
I sense that a lot of people are looking for a simple triangulation method with OpenCV, when they have two images and matching features.
While OpenCV contains the function cvTriangulatePoints in the triangulation.cpp file, it is not documented, and uses the arcane C API.
Luckily, Hartley and Zisserman describe in their excellent book “Multiple View Geometry” (in many cases considered to be “The Bible” of 3D reconstruction), a simple method for linear triangulation. This method is actually discussed earlier in Hartley’s article “Triangulation“.
I implemented it using the new OpenCV 2.3+ C++ API, which makes it super easy, and here it is before you.

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Hi!
I’ve been working on implementing a face image relighting algorithm using spherical harmonics, one of the most elegant methods I’ve seen lately.
I start up by aligning a face model with OpenGL to automatically get the canonical face normals, which brushed up my knowledge of GLSL. Then I continue to estimating real faces “spharmonics”, and relighting.

Let’s start!
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Hi,
Just reporting on a small achievement, part of a big project: Creating a browser plugin to display the Kinect depth map on screen.
The integration was fairly easy, which leads me to think that both FireBreath and OpenNI/Nite are pretty neat framework that are robust..
So let’s see how it’s done
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Hi!

I would like to present something I have been working on recently, a work that immensely affect what I wrote in the blog in the past two years…

To use it:
Go on this page,
Watch the short instruction video,
download the application (MacOSX-Intel-x64 Win32)
and make yourself a model!
It takes just a couple of minutes and it’s very simple…

This work is an academic research project, Please please, take the time to fill out the survey! It is very short..
The results of the survey (the survey alone, no photos of your work) will possibly be published in an academic paper.

Note: No information is sent anywhere in any way outside of your machine (you may even unplug the network). All results are saved locally on your computer, and no inputs are recorded or transmitted. The application contains no malware. The source is available here.

Note II: All stock photos of models used in the application are released under Creative Commons By-NC-SA 2.0 license. Creator: http://www.flickr.com/photos/kk/. If you wish to distribute your results, they should also be released under a CC-By-NC-SA 2.0 license.

Thank you!
Roy.

I want to share a small piece of code to do Laplacian Blending using OpenCV. It’s one of the most basic and canonical methods of image blending, and is a must exercise for any computer graphics student.
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WOW That was annoying! From the moment I started using a custom ROM on my Samsung Galaxy S2 (Cognition S2, to be exact), I started having issues with some apps.

Sometimes they won’t appear in search results, other times it will just say it’s not compatible. It drove me nuts!

Naturally I started with the forums – All the solutions there were about LCD DPI change. Funny, I never thought of that, but it did make sense. The only problem was that I never touched my DPI settings (Heck, I didn’t know I could).

(On a side note – tampering with the density is pretty cool… if you want to try it, you can download apps from the Market like LCD Density)

Back to my problem…
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A very simple thing, although I couldn’t find on Google some place to copy-paste off, so here it is:
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So, been working hard on my projects, and discovered some interesting things in Android possibilities for frame animation. Last time I was using an HTML approach, because of memory consumption issues with using ImageViews. However now my approach is using View.onDraw(Canvas) to draw BMPs straight off files, in an asynchronous way, and it seems to work pretty good.
Let me tell you how I did it
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Just wanted to share of some code I’ve been writing.
So I wanted to create a food classifier, for a cool project down in the Media Lab called FoodCam. It’s basically a camera that people put free food under, and they can send an email alert to the entire building to come eat (by pushing a huge button marked “Dinner Bell”). Really a cool thing.

OK let’s get down to business.
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