Rahul Erai

M Tech Computer Sc, IIT Kanpur

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Decoding cognitive states from brain fMRI scans

With Chittibabu, under the guidance of Dr Krithika Venkataramani

In this project, we investigated whether it is possible to decode what a person is thinking, analyzing his/her brain fMRI scans. Objective was to employ machine learning techniques on fMRI data, so that one could predict whether the person is seeing a picture, or reading a sentence. Since seeing and reading are associated with completely different parts of the brain, its theoretically possible to differentiate one from other. The biggest issue that we had to deal with was the highly hyper-dimensional dataset. fMRI scans typically lies in ~100,000 dimensional space. We proposed a new approach for dimensionality reduction, using which our results were significantly more accurate than the current state of the art method.

Results

results

Links

  • Project report
  • Presentation
  • fMRI dataset

  • Rotation invariant face detection based on Real Adaboost

    Under the guidance of Dr Amitabha Mukerjee

    Objective of this project was to develop a high performance face detection system, which works fine irrespective of the facial orientation. The popular Viola-Jones algorithm suffers from its inability to handle face images that are in different poses. To overcome this problem, we augmented the Viola-Jones algorithm with real adaboost algorithm, instead of the traditional discrete adaboost. This helped us to parallelize multiple detection cascades to gather, each one trained for a specific orientation of the face. Real adaboost gave us an additional opportunity to reduce the computation, by introducing a ranking scheme to rank the parallel cascades, so that after a few stages, one can stop the cascades with low rankings.

    Results

    results

    Links

  • Project report
  • Presentation
  • PIE dataset

  • Constructing 3D face models from depth and RGB data

    Under the guidance of Dr Pratwijith Guha

    This project was done as a part of my summer internship at TCS Labs, Delhi. We hacked Microsoft Kinect with the help of Point Cloud Library, so that it can be used to build 3D human face models. Firstly, we combined the RGB data with the depth data captured by the infrared camera in Kinect , to form a 3D model of the environment. Then a face detection algorithm was ran on the RGB stream so that the corresponding 3D face in the point cloud was able to extract. Now, having the partial 3D face clouds, next job was to stitch them together to form a complete model of the face. This was a 2 phase procedure. An initial alignment was done based on the Point feature histogram, followed by an optimization step that used a variant of Iterative Closest Point algorithm to minimize the alignment error. Once a 3D point cloud was obtained, a ball-pivoting surface reconstruction algorithm was applied get the mesh model of the face.

    Results

    results

    Links

  • Presentation

  • Adaptive fingerprint enhancement and cross-matching

    With Muralidharan, Mithun NK, Vijith KK, Saritha Murali, under the guidance of Smithamol B

    This was done as a part of my B tech project, and as a part of this project, we developed a new algorithm for fingerprint matching, which have high tolerance against smudged/dry fingerprints. We used a neural network preprocessing stage, which processed fingerprints adaptively, based on its nature[dry/normal/oily]. After that, we used a novel "distance vector" algorithm that we developed to match the fingerprints. Our paper on the same was accepted in three international IEEE conferences, namely ICACTE 2010, ICCSIT 2010 and ICUMT 2009. It was ranked among the top 10%-30% of all the papers in ICUMT 2009 .

    Links

  • Project Report