Monday, August 2, 2010

The Physical divide!

'Digital divide' refers to the gap between people with effective access to digital and information technology, and those with very limited or no access at all. There have been many theses and books written on this topic. I want to instead talk of the 'physical divide' which I would define as the gap between people living in a physical world with effective access to enhanced reality with digital technology and those with only a physical world. The difference between the two is subtle and needs to be explained. Its not that when we talk of digital divide, that there is no physical world. Its just that when I want to talk about the physical world I want to talk of the world itself rather than digital technology but I want to talk of the real world enhanced by use of digital technology. The so-called physical divide is addressed through a branch of computer vision and image processing generally referred to as 'augmented reality'. Augmented reality refers to the technology of combination of a real scene viewed by a user and a virtual scene generated by a computer that augments the scene with additional information. Mobile augmented reality which refers to providing augmented reality experiences on the mobile is the most developing and evolving technology today and has been described by MIT and Gartner in different studies as one of the top five disruptive technologies that will take centrestage in next 5 years.

We have heard of virtual reality. Without getting into the philospophy of 'reality', in contrast to virtual reality there is augmented reality. While virtual reality refers to computer-generated simulation environments that can simulate some places in the real (and imaginary) world, whereas augmented reality refers to augmentation or blending of real world scenes with computer generated additional information. On the spectrum between virtual reality, which creates immersive, computer-generated environments, and the real world, augmented reality is closer to the real world. This is why I chose to call it as a technology that addresses the physical divide. Augmented reality adds graphics, sounds, haptic feedback and smell to the natural world as it exists. Both video games and cell phones are driving the development of augmented reality. To take this to the horizon, let me give two examples of what this could mean in future. Think of a computer game that lets you drive a car on an F1 track. That would be virtual reality, but imagine instead of a video that has an actual recording of an F1 event which is augmented with your car which you are driving in a real F1 environment! Many of us know the Wii Nintendo game which was a pathbreaker in many ways. If you were to play, for example, a game of tennis in Wii, it would still be virtual reality. But imagine you playing a Wimbledon game with Roger Federer. If you could ever do that, that would be due to augmented reality.

As you can imagine, the applications are many. Augmented reality has extensive applications in the fields of medical science, entertainment, military training, engineering design, robotics, manufacturing, maintenance and repair, consumer design, hazard detection amongst others.

There are two commonly accepted definitions of augmented reality (AR) today.
  1. Azuma's definition says that AR has three components : it combines real and virtual, that it is interactive in real-time and that it is registered in 3D
  2. Milgram and Kishino defined in 1994 actually coined the term 'augmented reality' while defining what they called a reality-virtuality continuum. The continuum expands from a pure real world to a pure virtual world which is punctuated by mixed reality covering augmented reality, virtual reality and augmented virtuality.
To combine the physical and virtual world we need precise models, locations and optical properties of the viewer (or camera) and the display. The calibration of all the devices must be precise and need a mechanism to combine all local co-ordinate systems centered on the devices and the objects in a scene in a global co-ordinate system.

The biggest challenge for AR is a requirement of a very detailed description of the physical scene. Today AR struggles from finding optimal methods for registration of two distinct sets of images and keep them registered in real-time . Computer vision is sourcing some of the algorithms in this area for AR. AR also needs displays that can merge these two images.

Augmented reality systems are expected to run in the real-time so that the user can freely move in the environment, and are expected to show properly rendered augmented images. Thereby, implying that the two primary performance related issues with AR today are related to the update frequency of generating the augmented image and accuracy of the registration between the real and virtual image. While these may be easily stated, the challenges come from the technology barriers today for both registration and generation of augmented images.

Failure in proper registration and/or rendering leads to hardly desirable defects in the augmented scene and can show the real scene as less real than more virtual. AR requires that the augmentation has to have positive effect and that is a huge challenge today, not unsurmountable given the human desire to innovate always.

There are many AR solutions available today. The SixthSense augmented reality system lets you project a phone pad onto your palm and fingers and phone a friend -- without removing the phone from your pocket/purse.Some of the other AR solutions include the Arhrrrr - the augmented reality shooter, ARIS - the mobile media learning games, ARsights, eTreasure, LearnAR, SciMorph and the wikitude world browser.

Wireless applications are increasingly driving this technology into the mobile space where they offer a great deal of promise. Initially, AR required unwieldy headsets and kept users largely tethered to their desktop computers. The camera and screen embedded in smart phones and other mobile devices now serve as the means to combine real world data with virtual data; using GPS capability, image recognition, and a compass, AR applications can pinpoint where the mobile’s camera is pointing and overlay relevant information at appropriate points on the screen.

For example, the Wikitude World Browser is an augmented reality (AR) browser for the Android platform based on location-based Wikipedia and Qype content. It is a handy application for planning a trip or to find out about landmarks in your surroundings; 350,000 world-wide points of interest may be searched by GPS or by address and displayed in a list view, map view and “Augmented Reality” cam view. The latest version of WIKITUDE World Browser includes an Augmented Reality Photo Feature, which allows you to capture and share the AR camera view you experience through your mobile.

While I do not know when in future, if at all, we would be able to play up a tennis match with Roger Federer or Steffi Graf, AR is here to stay and has in many small ways has already helped many application areas. Outside of entertainment, in essential services such as medicine and surgery, there are already applications that help surgeons have a better view of the patient. Mobile AR will create many applications that will alter tomorrow's horizon. Like digital divide, whether physical divide continues to exist, we many never be able to tell, but changes are that the line between physical and virtual world will continue to blur in future.