Browsing All Posts filed under »Uncategorized«

Long overdue update. EuroScipy and SSLST 2011

September 5, 2011


Anybody reading my blog should have expected me to blog about the end of my GSoC. Sorry to disappoint, but I simply did not experience anything similar to an ending. On the contrary, I feel like things have barely started. Also, I apologize for one of the few posts here without pretty pictures! 🙂 For […]

K-Means for dictionary learning

July 10, 2011


One of the simplest, and yet most heavily constrained form of matrix factorization, is vector quantization (VQ). Heavily used in image/video compression, the VQ problem is a factorization where (our dictionary) is called the codebook and is designed to cover the cloud of data points effectively, and each line of is a unit vector. This […]

Dictionary learning sneak peek

June 24, 2011


Closing in on the goal of integrating J. Mairal’s dictionary learning in the scikit, I stitched together a couple of examples. The code is not yet integrated according to our standards, but here is the kind of results you can expect. Here is how a dictionary obtained from 8×8 patches of Lena looks like. Pretty […]

Summer of Code roadmap, part 1

June 12, 2011


After a little busy while, I have graduated and entered the summer vacation, which means time for serious GSoC work. So we had a little conference in order to discuss what will be done and when. We gathered quite a few code snippets since the official start of the project, but it’s now time to […]

First thoughts on Orthogonal Matching Pursuit

May 30, 2011


I am working on implementing the Orthogonal Matching Pursuit (OMP) algorithm for the scikit. It is an elegant algorithm (that almost writes itself in Numpy!) to compute a greedy approximation to the solution of a sparse coding problem: subject to or (in a different parametrization) subject to The second formulation is interesting in that it […]

An overview of dictionary learning: Terminology

April 15, 2011


My GSoC proposal is titled “Dictionary learning in scikits.learn” and in the project, I plan to implement methods used in state of the art research and industry applications in signal and image processing. In this post, I want to clarify the terminology used. Usually the terms dictionary learning and sparse coding are used interchangably. Also […]

Hello world!

March 30, 2011


This is the blog where I will post updates regarding my work on scikits-learn. I am applying as a GSoC 2011 student with the PSF for work on this machine learning library. I will also post related work that I do in the machine learning field. I hope to prove an enjoyable read for everybody […]