Ratchet Up

New Tools To Fix Images

Digital photographers could soon be able to erase unwanted elements in photos by using tools that scan for similar images in online libraries.

Research teams have developed an algorithm that uses sites like Flickr to help discover light sources, camera position and composition in a photo. Using this data the tools then search for objects, such as landscapes or cars, that match the original. The teams aim to create image libraries that anyone can use to edit snaps. [...]

To find suitable matching elements, the research duo's algorithm looks through a database of 2.3 million images culled from Flickr. “We search for other scenes that share as closely as possible the same semantic scene data,” said Mr Hays, who has been showing off the project at the computer graphics conference Siggraph, in San Diego. In this sense “semantic” means composition. So a snap of a lake in the foreground, hills in a band in the middle and sunset above has, as far as the algorithm is concerned, very different “semantics” to one of a city with a river running through it.

The broad-based analysis cuts out more than 99.9% of the images in the database, said Mr Hays. The algorithm then picks the closest 200 for further analysis. Next the algorithm searches the 200 to see if they have elements, such as hillsides or even buildings, the right size and colours for the hole to be filled. The useful parts of the 20 best scenes are then cropped, added to the image being edited so the best fit can be chosen. Early tests of the algorithm show that only 30% of the images altered with it could be spotted, said Mr Hays.

The other approach aims to use net-based image libraries to create a clip-art of objects that, once inserted into a photograph, look convincing. “We want to generate objects of high realism while keeping the ease of use of a clip art library,” said Jean-Francois Lalonde of Carnegie Mellon University who led the research.

To generate its clip art for photographs the team has drawn on the net's Label Me library of images which has many objects, such as people, trees and cars, cut out and tagged by its users. [...]

The algorithm developed by Mr Lalonde and his colleagues at Carnegie Mellon and Microsoft Research analyses scenes to find out the orientation of objects and the sources of light in a scene.

“We use the height of the people in the image to estimate the height of the camera used to take the picture,” he said. The light sources in a scene are worked out by looking at the distribution of colour shades within three broad regions, ground, vertical planes and sky, in the image. With knowledge about the position, pitch and height of the camera and light sources the algorithm then looks for images in the clip art database that were taken from similar positions and with similar pixel heights. The group has created an interface for the database of photo clipart so people can pick which elements they want to add to a scene.“ BBC

Sign of the Times: Stained-glass Pixels

The Gerhard Richter in the Cologne Cathedral is apparently magnificent as a series of pixels

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[Link to download a Hi Res version; via Boing Boing]

Technology Review: The Incapacitating Flashlight

Soon cops' flashlights might not only temporarily blind bad guys: they might also stop them in their tracks by disorienting them and making them nauseatingly sick. When suspects turn away or reel, cops or border-security agents can nab and handcuff them.

The flashlight, which is being developed for the Department of Homeland Security (DHS), uses a range finder to measure the distance to the target's eyes so that it can adjust the energy of the light to a level that won't cause permanent damage. Then it rapidly shoots out pulses of light from an array of ultrabright light emitting diodes (LEDs).

The flashes incapacitate a person in two different ways, says Robert Lieberman, CEO of Intelligent Optical Systems, based in Torrance, CA, which is making the device. The flashes temporarily blind a person, as any bright light would, and the light pulses, which quickly change both in color and duration, also cause what Lieberman calls psychophysical effects. These effects, whose effectiveness depends on the person, range from disorientation to vertigo to nausea, and they wear off in a few minutes.

It's not clear why the changing light pulses cause this effect, even though the effect has been well documented, Lieberman says. Helicopter pilots, for example, have been known to crash because they get disoriented by the choppy flashes of sunlight coming through the chopper's spinning blades. [...]

The LED flashlight comes with a few caveats. The person being targeted could easily look away, or he or she might be wearing heavily tinted glasses. And the device would not be useful to, say, a security agent who is chasing a suspected attacker. “It is designed to be used on someone coming at you,” Lieberman says. Also, the flashlight's effects are less during the day. But Lieberman notes that security agents will more likely face situations in which they need the device at night. [...]

Researchers at Intelligent Optical Systems are now analyzing combinations of wavelengths and light intensities that have the strongest effect on people while remaining safe. They also need to make the device smaller and easier to carry. Right now, it's about 15 inches long and 4 inches wide. This fall, the team plans to test the flashlight extensively on people at Penn State University's Institute of Non-Lethal Defense Technology.“ Technology Review: The Incapacitating Flashlight

Technology Review: A 3-D View of the Brain

Researchers at Thomas Jefferson University Hospital, in Philadelphia, have developed software that integrates data from multiple imaging technologies to create an interactive 3-D map of the brain. The enhanced visualization gives neurosurgeons a much clearer picture of the spatial relationship of a patient's brain structures than is possible with any single imaging methods. In doing so, it could serve as an advanced guide for surgical procedures, such as brain-tumor removal and epilepsy

The new imaging software collates data from different types of brain-imaging methods, including conventional magnetic resonance imaging (MRI), functional MRI (fMRI), and diffusion-tensor imaging (DTI). The MRI gives details on the anatomy, fMRI provides information on the activated areas of the brain, and DTI provides images of the network of nerve fibers connecting different brain areas. The fusion of these different images produces a 3-D display that surgeons can manipulate: they can navigate through the images at different orientations, virtually slice the brain in different sections, and zoom in on specific sections.

Currently, physicians typically view the images produced by MRI technologies individually, and they conceptually visualize what the images might look like combined. “Before this type of software package, I would put up an fMRI image and put up a regular MRI of the brain and try to match the two in my brain to try to get a 3-D sense of the right spot to make an incision,” says Ashwini Sharan, a neurosurgeon at the Jefferson Comprehensive Epilepsy Center. [...]

With the new software, surgeons are able to see the depth of the fibers going inside the tumor, shown as dashed lines, and the proximity of those on the outside, shown as solid lines. The lines are color-coded based on their depth; they range from dark red, which represents the deepest, to dark blue, which represents the shallowest. [...]

Having an interactive 3-D structure of the brain could be a critical tool for neurosurgeons in several ways. During a surgical procedure to remove a brain tumor, doctors must be careful not to tamper with the surrounding tissues, such as the fiber tracks that are vital to brain function. With the 3-D image, the surgeons could better understand the location and proximity of those fibers in relation to the tumor.

The new imaging also provides neurosurgeons who deal with disorders of the electrical systems of the brain with the ability to precisely determine the location of implanted electrodes used to monitor brain electrophysiological signals; such signals help physicians find the epileptic lesion to be removed by surgery. With the new software, electrodes can be accurately and automatically mapped.“ Technology Review: A 3-D View of the Brain

Sign of the Times: Mule Library

“Chiquito and Cenizo greet me with a bit of a snort and a flick of the tail. [...] They are known as bibliomulas (book mules) and they are helping to spread the benefits of reading to people who are isolated from much of the world around them. [...]

The idea of loading mules with books and taking them into the mountain villages was started by the University of Momboy, a small institution that prides itself on its community-based initiatives and on doing far more than universities in Venezuela are required to do by law. [...]

As the project grows, it is using the latest technology.

Somehow there is already a limited mobile phone signal here, so the organisers are taking advantage of that and equipping the mules with laptops and projectors.

The book mules are becoming cyber mules and cine mules.” BBC News

Your Printer Is Tattling On You

Many color laser printers leave an invisible tracking code printed in next-to-invisible yellow dots on your paper. This code contains the serial number of your machine and the exact time of printing.

The original rationale was to help track people looking to pass bad bills, but now color laser printers are ready to track everything and anything they produce.

Not everyone is happy about this, of course. The Electronic Frontier Foundation has developed an interface that you can use to decode the dots, if you of a mind. The image above gives you some indication of how coding—and now decoding—works.

“The DocuColor series prints a rectangular grid of 15 by 8 miniscule yellow dots on every color page. The same grid is printed repeatedly over the entire page, but the repetitions of the grid are offset slightly from one another so that each grid is separated from the others. The grid is printed parallel to the edges of the page, and the offset of the grid from the edges of the page seems to vary. These dots encode up to 14 7-bit bytes of tracking information, plus row and column parity for error correction. Typically, about four of these bytes were unused (depending on printer model), giving 10 bytes of useful data.” [Source]

JustinTV: Live Webcam 24/7 “Until I Die”

[The post below was composed several weeks ago, and has been sitting waiting to be posted. It was written in the first days of Justin.tv, which now has become something of a phenomenon. My skepticism stands.]

Lifecaching is a buzzword reflecting the fact that increasingly we are turning our lives into digital databases. We blog ourselves. MySpace ourselves. Shoot thousands of images of our kids with digital cameras. With all of the tools of media production at hand, we turn to our favored subjects, ourselves, and fire away. Or as Justin himself says: “I started Justin.tv becuase I thought it would awesome [sic] for people to see what is was like to be Justin.”

In the snap here, and AS I WRITE, Justin is being interviewed by something like German TV or the like. He's checking out his own phone before getting started. It slips out that he has had a “style consultant” help him with his clothes, although “he wasn't really into that.”

Justin has installed what looks to be an iChat camera off the side of his baseball cap, and begun to put this life “24/7 to the web”. There is also a live chat accompanying the feed with comments–mostly dopey–from people who are checking in. As I write this some “Heil Hitler” texter has claimed the chat space.

Anyway, this looks to be an interesting “my life as database” project to check in on the future. That is, if he keeps it up. As of now, Justin is “Live for 15 days, 19 hours, 19 minutes.” Already he has had three interviews, which, as I watch further, this seems to be about.

As I conclude he's talking with his Mom or Dad. He's explaining that people of their generation won't get it, and that “it's the people of his generation who are going to make them money. [...] We're publicizing the show!”

So much for conceptual art experiments in the '70's, this is something rather different.