• First Name: David
• Surnames: Gavilan Ruiz
• Nationality: Spanish (born in Barcelona in 1978)
• Current residence: Cambridge (UK)

Software Engineer with expertise in computer graphics & image processing. Worked on several game engines, VR & AR, and server-side rendering in the cloud.

Lead Software Engineer. Worked in an in-house cloud-based (AWS) server-side renderer using DirectX 10, OpenGL 3, C++11, C#, as well as cloud rendering using V-Ray SDK and Python. Worked on statistical models for 3D meshes and skeletal-based animation to create 3D avatars, and combined it with 2D garments using image processing techniques. Also developed some internal tools using WebGL and Node.js, and AR try-on projects using both Unity and Lens Studio. I’ve also had the role of Engineer Manager of a team of 8, responsible of the scrum process, line management, hiring, forecasting costs, and delivery.

Senior graphics programmer. Graphics programming and system wide optimizations, using Unreal Engine 4 and Disney’s in- house game engine, using mainly C++. Responsible for organizing teams to keep the game performance up in all our supported platforms (from WiiU to Playstation 4).

Graphics & system programmer. Programmed mobile games using Unity and C# on the client, and PHP and Node.js on the server side. Wide degree of responsibilities, from optimizing graphics, to game design, planning and hiring.

Graphics programmer. Programmed real time rendering techniques for the in-house Fox Engine. Fully developed several modern rendering techniques, from deferred lighting to real-time indirect illumination, for PC, Xbox360, and PS3. Worked closely with designers.

Graphics programmer. Worked as a system programmer implementing post-processing image filters for several video game graphic engines, as well as a graphics technology advisor.

Research assistant. Developed an application in Java and JAI that processed great amounts of data from hyperspectral imagery from Spanish satellite systems.

• 2005-2008: PhD on Computer Science at Tokyo Institute of Technology. Dissertation title: "Region-Based Image Abstraction for Retrieval and Synthesis", March 2008
• 2003-2005: Master on Computer Science at Tokyo Institute of Technology. Dissertation title: "Mobile Image Categorization and Retrieval using Color Blobs", March 2005.
• 2002-2003: Research assistant at Tokyo Institute of Technology
• 1996-2001: Higher Degree on Computer Science Engineering. Thesis title: "Advanced interfaces for e-Learning"

At a professional level, I can use Spanish, Catalan, Japanese, and English. Spanish and Catalan are my mother tongue languages. I started studying English when I was 8, and Japanese since I was 20. I have been using Japanese and English every day since I moved to Tokyo in 2002.

English Degrees: First Certificate & TOEFL (267/300)
Japanese Degree: Japanese Language Proficiency Level 1 (日本語能力試験1級)

• Monbukagakusho (Japan) scholarship, 2002-2008.
• Game award at DiVA (芸術科学会展), 2006.
• Top Computer Science student, Universitat Autònoma de Barcelona, 2001.
• San Juan Bosco High School, Graduated with honors, 1996.

Browse this web site. Also check my Real-time rendering blog in Medium, where I syndicate blog posts from a couple of sources.

Ph.D. Thesis

• "Region-based Image Abstraction for Retrieval and Synthesis", Tokyo Institute of Technology, January 2008, (.pdf 55MB), (small handout 19MB), Projects: Sketch2Collage

Journals

• D. Gavilan, H. Takahashi, M. Nakajima. “Image Categorization using Color Blobs in a Mobile Environment”, Computer Graphics Forum (EG 2003), Blackwell Publishing, 2003 , Vol. 22 , pp. 427-432
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Sketch-Based Evaluation of Image Segmentations Methods”, IEICE Trans. Inf. & Syst., 2007, E90-D, 156-164
• D. Gavilan, S. Saito, M. Nakajima. "Query-by-sketch based image synthesis", IEICE Trans. Inf. & Syst., 2008

International Conferences

• Orestis Sarakatsanos, Elisavet Chatzilari, Spiros Nikolopoulos, Ioannis Kompatsiaris, Dongjoe Shin, David Gavilan, Jim Downing, “A VR Application for the Virtual Fitting of Fashion Garments on Avatars”, XR4Fashion, IEEE International Symposium on Mixed and Augmented Reality (ISMAR) 4-8 Oct 2021.
• Konstantinos Oikonomou, Elisavet Chatzilari, Spiros Nikolopoulos, Ioannis Kompatsiaris, David Gavilan, Jim Downing, “Snapwear: A Snapchat AR filter for the virtual tryon of real clothes”, XR4Fashion, IEEE International Symposium on Mixed and Augmented Reality (ISMAR) 4-8 Oct 2021.
• D. Gavilan, H. Takahashi, M. Nakajima. “Color Blobs-based Image Retrieval in Broad Domains”, Proc. IWAIT 2005, January 2005, 115- 120
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Sketch-based perception model for evaluating color segmentations”, Proc. of APGV, ACM Press, 2005, 167-167
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Sketch-based fine-tuning of image segmentation methods”, Proc. of IWAIT 2006, January 2006, 393-398
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Morphological Sieves on Layered Images for Image Segmentation”, CDROM Proc. of Nicograph Intl 2006, June 2006, 6 pages
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Mobile Image Retrieval using Morphological Color Segmentation”, Proc. of ICMU 2006, October 2006, 51-58
• D. Gavilan, S. Saito, M. Nakajima. “Sketch-to-Collage: Query-by-sketch based image synthesis”, Proc. IIEEJ Img. Elec. & Vis. Comp. Workshop, November 2007, 8 pages (2A-3 CDROM).
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Evaluating Color Segmentation Methods with Mental Percepts”, CGI 2005 Posters
• D. Gavilan, S. Saito, M. Nakajima. “Sketch-to-Collage”, SIGGRAPH 2007 Posters, 1 page (CDROM)

National Conferences

• D. Gavilan, H. Takahashi, M. Nakajima. “Contents Classification in a Mobile Environment: Image Categorization using Color Blobs”, Proc. IEICE 2003, March 2003
• D. Gavilan, H. Takahashi, M. Nakajima. “Color Blobs based Image Categorization for Mobile Devices”, Proc. ITE 2003, July 2003
• D. Gavilan, H. Takahashi, M. Nakajima. “Ubiquitous Image Categorization using Color Blobs”, Proc. Nicograph 2003, November 2003
• D. Gavilan, H. Takahashi, M. Nakajima. “Image Indexing using Color Blobs”, Proc. IEICE 2004, March 2004
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Perception-based Evaluation of Segmentation Algorithms”, Proc. IPSJ 2005, March 2005
• D. Gavilan, H. Takahashi, S. Saito, M. Nakajima. “Morphological Scape Space based Color Segmentation”, Proc. IEICE, March 2006
• D. Gavilan, S. Saito, M. Nakajima. “Region-Based Retrieval and Manipulation of Image Collections”, Proc. of IPSJ, March 2007

If you want to refer to one of my publications, please don't make the same mistake as Google. They refer to my publications as D.G. Ruiz! Gavilan is not my middle name, but my surname. Please use D. Gavilan.

The problem is that in Spain we have two surnames, father's and mother's. In some of my old publications, I used to write both surnames, writing them in capital letters, as opposed to the first name. But then I noticed that I was being referenced wrongly in most cases. To avoid this, some people writes a hyphen between the two surnames, so I would be indexed "D. Gavilan-Ruiz", but I don't like hyphens, since it may seem that I should be called Mr. Gavilan-Ruiz (or "Gavilan-Ruiz san" in Japan), while the normal way in Spain is just using the first surname. Also, since Ruiz is not my middle name either, please don't write "D.R. Gavilan"!

Some artists, like Picasso, choose to be called by their mother's surname (Picasso's full name is Pablo Ruiz Picasso, and Ruiz is his father's surname). But I am no artist. So, please, just use "D. Gavilan" in my references. Thank you!