Cover Image: March 2011 Scientific American Magazine See Inside

Can You See Me Now?

A camera with a unique, spherical lens may bring single-shot gigapixel cameras closer to reality















Share on Tumblr



WIDE-ANGLE CLOSE UP: A still-life shot with a gigapixel camera prototype shows zoom-ins of a fabric weave. Image: Computer Vision Laboratory, COLUMBIA UNIVERSITY

Imagine snapping a panoramic picture from the top of the Empire State Building, then zooming in on a speck to reveal a quarter lying on the sidewalk. That’s the promise of single-shot gigapixel cameras—cameras that shoot images composed of at least one billion pixels, or picture elements. Apart from their obvious appeal to photographers, gigapixel images also hold tremendous potential for law enforcement and the military. Such high resolution would enable unmanned aerial vehicles to capture detail down to a license plate number while flying at altitudes too high to be spotted from the ground.

The Internet is already abuzz with sites, such as Google Earth, 360world.eu and GigaPan (created by Carnegie Mellon University, NASA and Google), that allow gigapixel digital photographs to be uploaded, viewed and shared across the Web. But these photographs actually consist of several megapixel-size images pieced together digitally. This is often accomplished using a long-lens digital single-lens reflex (SLR) camera placed atop a motorized mount. Software controls the movement of the camera, which captures a mosaic of hundreds or even thousands of images that, when placed together, create a single, high-resolution scene. The main drawback to this approach is that it can take up to several hours to complete the shoot, during which time lighting conditions may change and objects can move in and out of the frames.

Researchers are working to develop a camera that can take a gigapixel-quality image in a single snapshot. The U.S. Defense Advanced Research Projects Agency is investing $25 million over the next three and a half years into developing such compact devices. “We are no longer dealing with fixed installations or army tank units or missile silo units,” says Ravi Athale, a consultant to DARPA on this program. “[Fighting terrorism requires] an awareness of what’s going on in a wide area the size of a medium city.” Current satellite images or those taken from drones are extremely high resolution but very narrow in view, like “looking through a soda straw,” Athale says.

But today’s camera-size digital processors and memory are unprepared to manage gigapixel images, which contain more than 1,000 times the amount of information of megapixel images. (A 10-gigapixel image would take up more than 30 gigabytes of hard drive space.) Oliver Cossairt and Shree K. Nayar of Columbia University’s school of engineering, with funding from DARPA, have taken one promising approach: using computations to reduce such complexity. “Rather than thinking about it as capturing the final image, you’re capturing information you would need to compute the final image,” says Nayar, chair of Columbia’s department of computer science.

In a paper to be presented at April’s IEEE International Conference on Computational Photography in Pittsburgh, Cossairt and Nayar propose three compact gigapixel camera designs, two of which they built. Each relies on a unique ball-shaped lens that they selected for its simplicity—indeed, they built their first prototype around a crystal ball that they bought on New York City’s Canal Street. Unlike flatter lenses, which lose resolution toward the edges, a sphere’s perfect symmetry allows for uniform resolution. One of the Columbia lens designs resembles a fly’s eye, with half the sphere covered in small, hexagonal relay lenses that transmit images to an array of sensors just above them.

Of course, any advanced imaging technology invites concerns over privacy. Christopher Hills, a security consultant with Securitas Security Services who also runs the site gigapixel360.com, acknowledges that a landscape gigapixel image of a city could be scrutinized to see into the windows of homes. “Still, if you were to go to your window, someone in another nearby building or on the street would be able to see you. That’s why they make shades,” Hills observes.



This article was originally published with the title Can You See Me Now?.



Subscribe     Buy This Issue

Already a Digital subscriber? Sign-in Now
If your institution has site license access, enter here.

4 Comments

Add Comment
View
  1. 1. Circlea 12:44 PM 3/17/11

    is this article describing a Luneburg lens?? I have made Luneburg lens for radar, etc but I did not think a light Luneburg could be made---
    From Wikipedia:
    Each point on the surface of an ideal Luneburg lens is the focal point for parallel radiation incident on the opposite side. Ideally, the dielectric constant εr of the material composing the lens falls from 2 at its center to 1 at its surface (or equivalently, the refractive index n falls from \sqrt{2} to 1), according to

    n=\sqrt{\epsilon_r}=\sqrt{2-\left ( \frac{r}{R}\right ) ^2}

    where R is the radius of the lens. Because the refractive index at the surface is the same as a that of the surrounding medium, no reflection occurs at the surface. Within the lens, the paths of the rays are arcs of ellipses.

    The practical implementation is normally a layered structure of discrete concentric shells, each of a different refractive index. These shells form a stepped refractive index profile that differs slightly from Luneburg's solution. This kind of lens is usually employed for microwave frequencies, especially to construct efficient microwave antennas and radar calibration standards.

    Reply | Report Abuse | Link to this
  2. 2. jtdwyer 10:39 AM 3/18/11

    What the military needs is the capabilities of the Polaroid type photos in the movie "Blade Runner" that allowed 3d interrogation - scanning through a doorway to investigate the next room, viewing down into the bathtub, etc. Now that'd be great for urban warfare! Then you can guide your your nano-aircraft mounted gamma-ray laser to 'illuminate' Osama down in room 42... Wait - that's not Osama - that's me!

    Reply | Report Abuse | Link to this
  3. 3. BoydAnne 05:24 PM 3/18/11

    On the subject of the need for window blinds to prevent unwanted capture....
    Click into the "16 Gigapixel panorama-photo of Prague" link here http://www.360cities.net/prague-18-gigapixels
    1/ Use the field of view pionter at the top left to bring the field of view to look northwards, actually actually best a few degrees to the west of north.
    2/ At the bottom of the view see the first row of apartments with red rooves which is the first line of rooves in the field of view.
    3/ Spot is a inset balcony in that line of rooves along the bottom of the picture slightly to the left of botton centre. Zoom in towards the inset balcony.
    4/ As you do so spot the man seated in the window below and zoom in on him.

    Reply | Report Abuse | Link to this
  4. 4. Wayne Williamson in reply to BoydAnne 06:48 PM 3/18/11

    Very funny...just goes to show that nothing in the open is secret...is that a camera in his hand;-)

    Reply | Report Abuse | Link to this
Leave this field empty

Add a Comment

You must sign in or register as a ScientificAmerican.com member to submit a comment.
Click one of the buttons below to register using an existing Social Account.

More from Scientific American

See what we're tweeting about

Scientific American Editors

More »

Free Newsletters


Get the best from Scientific American in your inbox

Solve Innovation Challenges

Powered By: Innocentive

  SA Digital
  SA Digital

Science Jobs of the Week

Email this Article

Can You See Me Now?: Scientific American Magazine

X
Scientific American Magazine

Subscribe Today

Save 66% off the cover price and get a free gift!

Learn More >>

X

Please Log In

Forgot: Password

X

Account Linking

Welcome, . Do you have an existing ScientificAmerican.com account?

Yes, please link my existing account with for quick, secure access.



Forgot Password?

No, I would like to create a new account with my profile information.

Create Account
X

Report Abuse

Are you sure?

X

Institutional Access

It has been identified that the institution you are trying to access this article from has institutional site license access to Scientific American on nature.com. To access this article in its entirety through site license access, click below.

Site license access
X

Error

X

Share this Article

X