Lokvani Talks To TR100 Winner Ramesh Rasker
Ranjani Saigal

(This article is sponsored by Attorney Trupti Patel)

Dr. Ramesh Raskar, a research scientist at Mitsubishi Electric Research Lab in Cambridge, MA, is one of the nine Indians who have won the prestigious TR100 award given by the MIT Technology Review magazine. The chosen 100 (TR100) represent a group under the age of 35 that is using technology to transform the world around us. According to the Technology Review magazine Raskar was chosen for his work on building large computer display systems that seamlessly combine images from multiple projectors. This work may lead to new applications in entertainment, image-guided surgery, and user interfaces.

Ramesh Raskar joined MERL as a Research Scientist in 2000 after his doctoral research at U. of North Carolina at Chapel Hill, where he developed a framework for projector based displays. His work spans a range of topics in computer vision and graphics including projective geometry, non-photorealistic rendering and intelligent user interfaces. He has developed algorithms for image projection on planar, non-planar and quadric curved surfaces that simplify constraints on conventional displays and has proposed Shader Lamps, a new approach for projector-based augmented reality. Current projects include composite RFID (RFIG), multi-flash non-photorealistic camera for depth edge detection, locale-aware mobile projectors, high dynamic range video, image fusion for context enhancement and quadric transfer methods for multi-projector curved screen displays.

Dr. Raskar has also received the Mitsubishi Electric Information Technology R&D Award 2003, Global Indus Technovator Award 2003, instituted at MIT to recognize the top 20 Indian technology innovators on the globe and the Mitsubishi Electric Valuable Invention Award 2004 His papers have appeared in SIGGRAPH, Eurographics, IEEE Visualization, CVPR and many other graphics and vision conferences. He has taught courses and has served as a member of international program committees at major conferences. He is a member of the ACM and IEEE.

Dr. Raskar took us on a tour of his lab at MERL and gave us some insights into his work and life.

Lokvani: What problem does your work on seamlessly combining images from multiple projectors try to address?

Raskar: The motivation for the work was a desire to replicate the shift that happened in the world of computing in the world of displays. Originally supercomputers were one large unit, expensive to build and difficult to maintain. Today supercomputers are built by weaving together off-the shelf Linux boxes.

Large computer displays, like the kind found in digital cinema, IMAX theaters, planetariums or scientific visualization centers are commonly created using a single expensive high powered projectors. Such a system is not easy to maintain since a failure in one of the projectors would bring the entire system down. These systems are not very flexible and cannot be upgraded easily.

We create large computer displays by automatically stitching together images that are beamed by off-the shelf projectors. This system is cheaper to build and is very flexible. We can recreate a good quality image rather easily even if a projector fails which makes fault tolerant. Plus individual units can be upgraded anytime allowing the owner to ride the technology and cost curve.

Lokvani: Does this technology have applications beyond the entertainment industry?

Raskar: The technology has a variety of applications. In the future, every light bulb could be replaced with a projector at home and at the work place. This could enable us to beam a variety of images on different surfaces. When you travel for work, you may be able to have live teleconferencing with different members of your family and thus be able to create a virtual reality “at-home” feel.

Lokvani: Could you tell us a little about your other innovations viz the multi-flash camera for shape boundary detection and RFIG?

Raskar: Imagine a camera, no larger than existing digital cameras, that can directly create drawings that you see in car manuals or anatomy books. As we know, a flash to the left of a camera creates a sliver of shadow to the right of each silhouette in the image. We add a flash on the right, which creates a sliver of shadow to the left of each silhouette, a flash to the top and bottom. Simply by observing the shadows, after image processing, we can robustly find all the pixels corresponding to shape boundaries. This is a strikingly simple way of calculating the so called depth edges and solves a fundamental problem in Computer Vision. Since we can distinguish between color boundaries and shape boundaries, we can use these edges to create images that look like technical illustrations and line drawings. We have a built a new type of laparoscope by adding multiple light fibers around the tiny camera of the laparoscope. Inside the patient, the lit fibers cast shadows around lesions or minute shapes in different directions and after image processing, we can provide live images during examination or surgery that are much easier to understand.

RFIG is a photosensing wireless tag which acts as a radio frequency identity and geometry transponder. Think of it as a millimeter-accurate location aware RFID tag. We find the location of the photosensing RFID tag using a handheld ‘projector’ which looks like your TV remote control that beams infrared light. We have introduced a novel technique that we call interactive projection to allow a user to interact with projected information e.g. to navigate or update the projected information.

Lokvani: You have been a successful innovator and won several prestigious awards. To what do you attribute you success?

Raskar: The work environment. MERL allows me to take my ideas and provides me all the resources to work on it. The flexible structure of the organization allows me to draw upon people who have different expertise and work in different areas. MERL allows us to participate in any aspect of innovation whether it is doing fundamental research, acquiring patents or transform your idea into a business opportunity. This has greatly contributed to my success.

I am very grateful for all the guidance and support I have received from my advisor at the University of North Carolina, Dr. Henry Fuchs and Dr. Greg Welch and the director of MERL, Dr. Joe Marks.

I am most grateful to my older brother, Prakash, who has always been there to provide a sense of balance. He picks me up when I am down and helps me understand that awards are really nothing more than a small token of appreciation for my work.

Lokvani: You have included the Sanskrit verse in your web page that gives the value of pi to ten decimal places. Do you have a special interest in the area of Vedic Mathematics?

Raskar: People in the US often ask me why Indians are so mathematically inclined. This made me investigate our history a little to understand where this interest comes from. This search led me to this verse and others which I find fascinating.

Ever since I put this verse on my web page I have received calls from many interesting people including a film producer who is making a film on the origins of pi.

Lokvani: What are your plans for the future?

Raskar: On the professional front I hope to continue to work on the different technologies that we have developed. Venture Capitalists have shown interest in some of the technologies.

On the personal front, I am still single, but too busy and hope I can find the right woman!

Lokvani: On behalf of Lokvani, I wish you the very best of luck in finding a soul mate. We thank you for your time.

Raskar: Thank you.

To learn more please visit Dr. Raskar's website at

Email Article | Share your Comments

Comments :
Post a new message

You may also access this article through our web-site

Home | About Us | Contact Us | Copyrights Help