1)      Touch Adaptive Image Segmentation and Object Modeling (NVIDIA Research): Formulated algorithms for touch adaptive segmentation and object modeling for Nvidia Tegra/ Android tablet devices using C/CUDA. (2012)

 2)      Feature Based Tracking and Pose Estimation (Qualcomm Research): Contributed to algorithmic improvements for the tracking and pose estimation routines in Qualcomm Vuforia SDK framework for Android, iOS environments. (2011)

 

 

 

 

 

University Research – Active

 

Affordance based Cognitive Computer Vision

 

 

51. KM. Varadarajan, ‘Anti-Mirror Neuron System Model for Affordance based k-TR Common Coding Theory’, Conference of the International Society of Psychophysics – ISP, (2013-TBS).

52. KM. Varadarajan, ‘Learning Surprise and Saliency Affinities for k-TR Semantic Affordance Aberrations’, International Conference on Philosophy, Artificial Intelligence and Cognitive Science - Turing, Manila, Philippines (2012).

53. KM. Varadarajan, M. Vincze, ‘Attention Mechanisms of the k-TR Model to Visual Perception’, Roverto Attention Workshop – RAW, Roverto, Italy (2011).

54. KM. Varadarajan, ‘k-TR: Karmic Tabula Rasa – A Theory of Visual Perception’, Conference of the International Society of Psychophysics - ISP, Herzliya, Israel (2011).

 

  

5) Recognition by Component Affordances (RBCA): Created a new theory to object recognition using component affordances. Designed and implemented innovative computer vision algorithms – range processing, object and part semantic segmentation, 3D modeling, affordance ontology mapping, part connectivity calculus, graph matching, view clustering using Non-Negative Matrix Factorization (NNMF), inference mechanisms leading to a Visual Cognitive Engine (VCE) supporting RBCA.

 

Notes:

RBCA defines objects in terms of their constituent parts and their part affordances along with the topogeometrical relationship between the parts and scale information. For example, a chair is defined as composed of two surfaces providing 'support-ability' or capable of providing supports that are staggered and orthogonal to each other and for objects that are typically the size of a human foream. The Visual Perception pipeline uses RGB-D data to recognize such parts and uses them in a sub-graph matching procedure to recognize different objects.

Ref:

26. KM. Varadarajan, M. Vincze, ‘Learning Affordance Co-occurences from Wearable Camera Data’, IEEE Computer Vision Conference on Pattern Recognition -CVPR Workshop on Human Activity Understanding from 3D Data (2013-TBS).

39. KM. Varadarajan, M. Vincze, ‘Affordance Sequencing for Task Representation’, IEEE International Symposium on Robots and Human Interactive Communication - RO-MAN (2013-TBS).

 

 6)  AfNet– The Affordance Network: Developed AfNet, an open affordance computing initiative, that builds affordance knowledge ontologies in terms of afbits (affordance bits) defined by the user community. The project is hosted at theaffordances.net and provides 68 base affordance features (25 structural, 10 material, 33 grasp), over 200 object category definitions in terms of 4000 afbits. 

8)     Augmented Virtuality based Telepresence for Mining Robots: Designed an Augmented Virtuality based visualization system for control of mining robots for semi-autonomous operation in critical environments.

10)    Cognitive Event Recognition: Designed and implemented a novel ‘Bio-inspired Scene Analysis System for Video Indexing and Retrieval’ using the concept of mirror neurons. It uses an Object - Action - Event recognition pipeline employing mirror neuron networks, object state, event state graphs, hierarchy and ontology.

13)    Panoramic Video Tracking: Designed and implemented a novel ‘Real-Time Panoramic NTSC Video Human Tracking System based on the Kalman Filter’ on fixed point TMS320C6416 DSP processor, with Pipeline, memory & stack management, Logic and instruction level optimization, Hardware and software trade-offs.

14)    Learning for Automated Target Recognition: Researched and built modules for innovative Incremental learning (IncLeDec), Environmental context adaptation, Concept drift and Knowledge assimilation for Decision trees based Naive Bayes Classifier (NBC) and other ensemble learning schemes operating on target image chips for Army/Navy SBIR on Perpetual learning and knowledge mining for Automated Target Recognition (ATR).

18)    OpenCV based Image Analysis: Implemented and analyzed Lambertian surface shading. Implemented and tested Mean shift & K-means segmenters and analyzed the results of the segmentation with respect to its parameters. Analyzed the performance of Birchfield-Tomasi stereo algorithm based on various parameters such as occlusion penalty, match-reward, reliability etc.

22)    Algorithms for Bio-rendering: Developed couple of novel bio-inspired algorithms for rendering tree growth – Fissured bark geometry and Semi-random cylindrical trunk with astroidal base explosion geometry.

23)    Game Design: Designed and implemented Intelligent games – ‘Bantumi (Pallanguzhi)’ and ‘Dragon Eclipse’ and implemented using Microsoft Developer Studio – C with OpenGL.

24)    WYHIWYS  Device: Designed, implemented, tested a novel algorithm- a ‘What You Hear Is What You Speak' (WYHIWYS) device, incorporating direct and indirect paths, reverberant fields, effects of voiced segments, vocal tract vibrations, attenuation effect of tissues, cancellous bones and the Eustachian tube.

25)    Speech Recognizer: Built a simple speech recognizer for distinguishing between numerals using Mel-Frequency Cepstral Coefficients (MFCC) feature extraction, Template description by training and Pattern matching on Dynamic Time Warped (DTW) feature vectors.

26)    Linear Predictive Coding: Developed a tool for Linear Predictive Coding (LPC) analysis by way of computation of autocorrelation matrix and implementation of Levinson Durbin recursive solution.

27)    Room Acoustics & HRTF Analysis: Estimated and analyzed the Impulse response and Reverberation time of an enclosed space. Analyzed the deviant behavior of Head Related Transfer Function (HRTF) with sample selection. Examined role of pinnae in Localization, Front-back and Back-front confusion, Source direction identification using MIT Fred KEMAR data.

28)    Acoustics Simulator: Designed a multi-stage IIR Reverberator filter to simulate reverberations, with ability to control variation due to different surfaces, relative phase delay and multi-path effects.

29)    Divider for DSP Processors: Developed and implemented a novel Frequency analyzer circuit and a Synchronous constant divider for DSP based real-time image processing (tested using OrCAD).

30)    Analog Devices DSP programming: Implemented and tested JPEG & other Image compression algorithms, Speech echo cancellation algorithms, Gabor filter based recognition on ADSP 2192-12 at IIT DSP Learning Program.

31)    TI DSP programming: Implemented and tested Code Excited Linear Prediction (CELP) Vocoders, Adaptive noise reduction, FIR, IIR filters and various other Real-time image and speech filtering applications on DSK TMS320VC5416, C6713 processors using Code Composer Studio (CCS) C and Linear assembly programming.

32)    Information Theoretic Lossless Compression: Implemented and analyzed Huffman coding (Global statistics and Locally adaptive statistics), Lempel-Ziv coding, Run-length coding, QM Arithmetic coding on different data types.

33)    Scalar and Vector Quantization: Designed and implemented a 3-bit and a 5-bit Lloyd-Max Scalar quantizer with support for compact codes and analyzed results based on rate-distortion curves and average code word lengths. Designed, implemented and analyzed a Lloyd-Max Vector quantizer using LBG splitting and GLA. Implemented and analyzed a Tree Structured Vector Quantizer (TSVQ) using multiple vector dimensions and codebook sizes.

34)    JPEG and MPEG - Analysis and Enhancement: Analyzed rate-control in JPEG, developed and implemented a deblocking filter to remove blocking artifacts in reconstructed images, studied and analyzed macro blocks and motion vectors in MPEG-2, compared MPEG-1 and MPEG-2 based on PSNR/frame, bits/frame and motion vectors. Implemented a fast motion vector search algorithm (Diamond search) for MPEG codec.

35)   Predictive Lossless Compression: Surveyed major domains of modern lossless data compression: Dictionary based approaches (LZ family), Block sorting methods (BWT based), Predictive mapping based methods (PPM, PPM*, PAQ family and its models; model mixing; contexts) and performed comparative analyses of the performances. Designed Evolutionary / Swarm optimized genetic algorithms based schemes for context mixing in PAQ. Surveyed progressive trends in H.264, G.729, DRM, HD-DVD and Blue Ray implementations.

36)    Dynamic Topology Design: Designed and implemented ‘A Power Level based Wireless Sensor Network (WSN) Deployment Scheme for Outage Reduction using Irregular Hexagonalization’ by way of modeling the wireless communication channel. The dynamic hex network topology designed takes into account flat fading through Rayleigh, Rician, Log-Normal, Nakagami, Weibull Distributions, reducing the outage probability.

37)    Airborne Networks: Tested UC’s MDP/MARP protocol suite - Mobility aware routing schemes for airborne networks using QualNet emulator (Air-Force SBIR).

38)    Node Localization: Tested and analyzed the performance of various localization techniques in wireless sensor networks, clock skews and error accumulation in TPSN two-way time synchronization.

39)    Wireless Environment Characterization: Conducted an experiment and analyzed the Path loss, noise and PRR variations of wireless links in a typical environment using TMOTE SKY motes employing TinyOS programming. Numerous other tests using TinyOS were performed.

40)    Data Rate Optimization: Analyzed and optimized network data rates using Linear programming in AMPL and NEOS optimization server.