|
Monday, March 12, 2007 TR10: Digital Imaging, ReimaginedRichard Baraniuk and Kevin Kelly believe compressive sensing could help devices such as cameras and medical scanners capture images more efficiently. By Kate Greene
This article is one in a series of 10 stories we're running this week covering today's most significant emerging technologies. It's part of our annual "10 Emerging Technologies" report, which appears in the March/April print issue of Technology Review. Richard Baraniuk and Kevin Kelly have a new vision for digital imaging: they believe an overhaul of both hardware and software could make cameras smaller and faster and let them take incredibly high-resolution pictures. Today's digital cameras closely mimic film cameras, which makes them grossly inefficient. When a standard four-megapixel digital camera snaps a shot, each of its four million image sensors characterizes the light striking it with a single number; together, the numbers describe a picture. Then the camera's onboard computer compresses the picture, throwing out most of those numbers. This process needlessly chews through the camera's battery. Baraniuk and Kelly, both professors of electrical and computer engineering at Rice University, have developed a camera that doesn't need to compress images. Instead, it uses a single image sensor to collect just enough information to let a novel algorithm reconstruct a high-resolution image. At the heart of this camera is a new technique called compressive sensing. A camera using the technique needs only a small percentage of the data that today's digital cameras must collect in order to build a comparable picture. Baraniuk and Kelly's algorithm turns visual data into a handful of numbers that it randomly inserts into a giant grid. There are just enough numbers to enable the algorithm to fill in the blanks, as we do when we solve a Sudoku puzzle. When the computer solves this puzzle, it has effectively re-created the complete picture from incomplete information. Compressive sensing began as a mathematical theory whose first proofs were published in 2004; the Rice group has produced an advanced demonstration in a relatively short time, says Dave Brady of Duke University. "They've really pushed the applications of the theory," he says. Kelly suspects that we could see the first practical applications of compressive sensing within two years, in MRI systems that capture images up to 10 times as quickly as today's scanners do. In five to ten years, he says, the technology could find its way into consumer products, allowing tiny mobile-phone cameras to produce high-quality, poster-size images. As our world becomes increasingly digital, compressive sensing is set to improve virtually any imaging system, providing an efficient and elegant way to get the picture. |




Comments
Gaetano Marano on 03/15/2007 at 8:27 AM
51
I'm a supporter of saving the Hubble Space Telescope moving it near the ISS to repair/upgrade/use it in the next 20+ years
I think that Hubble can still give much better images and scientific results if upgraded with the BEST (and very advanced) sensors/computers/software/image-processing technologies available in 2015, 2020, 2025, etc.
I explain my proposals about Space in my articles here: www.gaetanomarano.it/articles/articles.html
and my suggestions about saving/moving the Hubble in my UniverseToday forums' thread here: http://www.bautforum.com/showthread.php?t=55399
the NASA administrator Mr. Griffin said yesterday that, without any servicing, the HST can survive until 2010, while, after the planned (and LAST) Hubble Servicing Mission (SM4) in 2008, it may have three more years of life, surviving (at least) until 2013
unfortunately, also after SM4 (that use to-day/past technologies) the quality of the HST images always remains the same of to-day/past observations (that is pretty close to the quality some earth telescopes will reach around 2010)
the best idea is to design, develop, build and launch a new and better space telescope, but I doubt will be easy to find the funds to do that if we consider that (so far) the total costs of the "small" Hubble reached $6 billion (1/3th to build it and 2/3 for its launch and 16+ years of servicing)
all new (sensors/computers/software/image-processing) technologies can be applied also to earth telescopes, but, unfortnately, the latter have some limits due to the atmosphere, weather, air/light pollution, turbulences, etc.
juts imagine if, thanks to next years' hi-tech upgrades, Hubble will give us images 3, 10, 50 times better than now... revealing us (soon!) ALL the secrets of the Universe!
.
jsessex on 03/15/2007 at 8:02 PM
11
Gaetano Marano on 03/16/2007 at 11:26 AM
51
that's true, Hubble and ISS are in two different orbits and the Shuttle has not enough propellent to move the Hubble near the ISS
infact, in the BAUT thread linked in my post (and in other threads linked in the main thread) I suggest to move it with multiple Progress/ATV/Parom automated missions launched from Guiana
.
igorc on 03/17/2007 at 3:35 PM
3
Igor.
http://nuit-blanche.blogspot.com/search/label/compressed%20sensing