Professional experience presentation

Nicolau L. Werneck, PhD

São Paulo, Brazil

19 November 2013

Personal background

Always loved computers, started coding beforecollege.Interest in science and arts in general, includingmusic, photography and cinema.Predisposition to academic life, doing research andinterdisciplinarity.

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Graduation

Graduated in Electrical Engineering at UFMG, withemphasis on computation.Favorite subjects: signal processing, optimization.Worked at the CEFALA lab, studied many signalprocessing and pattern recognition problems.→ Recognition and synthesis of face, speech and musical

instruments; Fingerprint recognition; Visual tracking.→ Concern for building physical and probabilistic models

of the studied phenomena.

Internship at a biotech start-up, applying statisticalpattern recognition to genetic data from bovines.

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Masters

Masters in Electrical Engineering at UNICAMP.Continued undergrad research on electric guitars.Physics of vibrating strings, electronic distortionsand timbre perception.Conducted several experiments:→ Detection of non-linear effects in string vibration.→ Parameter estimation of electronic circuits.→ Sensibility of distortion perception.

Favorite subjects: ML, Cog. Sci, Computer Vision.

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Doctorate

Worked at the LTI, USP, supervised by Prof. AnnaHelena Reali Costa.→ Lab topics: computer vision, mobile robots, task

planning, RL, POMDPs, policy reuse, MAS.

Eventually started working with Computer Visionapplied to Mobile Robotics.“Disenchanted” with stereo rigs and with methodsbased on point or line extraction.Started studying edgel-based monocular vision,hoping to build solid models of environments.

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Research Motivations

Create environment models more suitable forrobotics, withs solids and “meaning”.Explore the “Manhattan world” assumption.Monocular operation and good computationalperformance. Be able to run on a smartphone.To handle distorted and omnidirectional images.

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Research Focus

Research started with simpler problems, assumingrectilinear motion and 2D models. [1, 2, 3]

We noticed rotation is a great nuisance for mapping, butLine-based

vision+ “Manhattan world”

assumption → Decouple orientation &position estimation.

So we started to study orientation estimation.6 / 11

Research Proposal

Corisco is an edgel-based orientation-estimation method.It minimizes an objective function defined withM-estimation, using RANSAC and FilterSQP. [4, 5]

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Research ResultsCorisco was implemented in Python and C, and isavailable at http://github.com/nlw0/corisco.

Compared to Snavely et al. 2006, Denis et al. 2008 andother methods.

Future work: SLAM and calibration.

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Google work

Google uses scanners that take pictures of openbooks. A solid model is necessary for dewarping.They wanted a new algorithm to be used in anopen-source “lightweight” book scanner.I proposed a square mesh model, and to imposeinextensibility by using constrained optimization.Implemented just a very simple prototype. TodayI’m working on a purely monocular method.

This work led me to study FilterSQP, used in Corisco.

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Geekie work

The company uses Item Response Theory (IRT) toevaluate the performance of students.I implemented a better parameter estimationalgorithm for the IRT analyses.The current code has already been used to analyze100k tests.Currently working on an information system forresearch and analytics tasks. (Kaiju framework.)

Other activities: BIB design solver, analytics.

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Future plans

Get back at working with computer vision.Contribute to creating great CV tools and productsfor the industry and academy.Research ambitions: monocular vision method tocreate solid environemnt models.

Thank you!

Nicolau Werneck <nwerneck@gmail.com>

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Corisco Examples

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Corisco Examples

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Corisco Examples

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Corisco Examples

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Corisco Examples

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Corisco Examples

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Corisco Examples

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Corisco Examples

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Referências Bibliográficas[1] Nicolau Leal Werneck, Flávio Sales Truzzi, and Anna Helena Reali

Costa. Medição de distância e altura de bordas horizontais com visãomonocular linear para robôs móveis. In Workshop de VisãoComputacional, São Paulo, SP, Brasil, 2009. Universidade PresbiterianaMackenzie. URL http://nwerneck.sdf.org/almoxarifado/59760_WerneckTruzziCosta.pdf.

[2] Nicolau Leal Werneck and Anna Helena Reali Costa. Monocular visualmapping with the Fast Hough Transform. In Workshop de VisãoComputacional, Presidente Prudente, SP, Brasil, 2010. FTC-UNESP.URL http://iris.sel.eesc.usp.br/wvc/anais_WVC2010/artigos/oral/72827.pdf.

[3] Nicolau Leal Werneck and Anna Helena Reali Costa. Mapping withmonocular vision in two dimensions. International Journal of NaturalComputing Research, 1(4):56–65, 2010. URLhttp://nwerneck.sdf.org/almoxarifado/WerneckCosta10.pdf.

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[4] Nicolau Leal Werneck and Anna Helena Reali Costa. Speeding upprobabilistic inference of camera orientation by function approximationand grid masking. In Gladimir Baranoski and Vaclav Skala, editors,WSCG 2011 Communication Papers, pages 127–134, Plzen, CzechRepublic, 2011. UNION Agency. URLhttp://nwerneck.sdf.org/almoxarifado/nic-wscg2011.pdf.

[5] Nicolau Leal Werneck and Anna Helena Reali Costa. Corisco: Robustedgel-based orientation estimation for generic camera models. Imageand Vision Computing, 2013? Accepted, final version in preparation.

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