A new approach to computer vision object recognition: simulated heat-mapping:
The heat-mapping method works by first breaking an object into a mesh of triangles, the simplest shape that can characterize surfaces, and then calculating the flow of heat over the meshed object. The method does not involve actually tracking heat; it simulates the flow of heat using well-established mathematical principles, Ramani said. …
The method accurately simulates how heat flows on the object while revealing its structure and distinguishing unique points needed for segmentation by computing the “heat mean signature.” Knowing the heat mean signature allows a computer to determine the center of each segment, assign a “weight” to specific segments and then define the overall shape of the object. …
“A histogram is a two-dimensional mapping of a three-dimensional shape,” Ramani said. “So, no matter how a dog bends or twists, it gives you the same signature.”
In other words, recognizing discrete parts (like fingers or facial features) of an object in front of the camera should be much more accurate with this approach than with older techniques like simple edge detection. Uses for real-time recognition are apparent (more accurate Dance Central!), but it seems like this would also be a boon for character animation rigging?
(Via ACM TechNews)
Herman Melville on the Nature of Color
From Moby Dick, chapter 42, “The Whiteness of the Whale”:
Is it that by its indefiniteness it shadows forth the heartless voids and immensities of the universe, and thus stabs us from behind with the thought of annihilation, when beholding the white depths of the milky way? Or is it, that as in essence whiteness is not so much a color as the visible absence of color, and at the same time the concrete of all colors; is it for these reasons that there is such a dumb blankness, full of meaning, in a wide landscape of snows - a colorless, all-color of atheism from which we shrink? And when we consider that other theory of the natural philosophers, that all other earthly hues - every stately or lovely emblazoning - the sweet tinges of sunset skies and woods; yea, and the gilded velvets of butterflies, and the butterfly cheeks of young girls; all these are but subtile deceits, not actually inherent in substances, but only laid on from without; so that all deified Nature absolutely paints like the harlot, whose allurements cover nothing but the charnel-house within; and when we proceed further, and consider that the mystical cosmetic which produces every one of her hues, the great principle of light, for ever remains white or colorless in itself, and if operating without medium upon matter, would touch all objects, even tulips and roses, with its own blank tinge - pondering all this, the palsied universe lies before us a leper; and like wilful travellers in Lapland, who refuse to wear colored and coloring glasses upon their eyes, so the wretched infidel gazes himself blind at the monumental white shroud that wraps all the prospect around him. And of all these things the Albino Whale was the symbol. Wonder ye then at the fiery hunt?
Cryptochrome
Research continues on whether humans (and other animals) have the ability to perceive magnetic fields:
Many birds have a compass in their eyes. Their retinas are loaded with a protein called cryptochrome, which is sensitive to the Earth’s magnetic fields. It’s possible that the birds can literally see these fields, overlaid on top of their normal vision. This remarkable sense allows them to keep their bearings when no other landmarks are visible.
But cryptochrome isn’t unique to birds – it’s an ancient protein with versions in all branches of life. In most cases, these proteins control daily rhythms. Humans, for example, have two cryptochromes – CRY1 and CRY2 – which help to control our body clocks. But Lauren Foley from the University of Massachusetts Medical School has found that CRY2 can double as a magnetic sensor.
Vision is amazing, even more so when you take into account the myriad other things that animals and insects can detect beyond just our “visible” EMF spectrum. See also: box jellyfish with their surprisingly complex (and human-like) set of 24 eyes.
"3D films require us to focus at one distance and converge at another….So the “CPU” of our perceptual brain has to work extra hard, which is why after 20 minutes or so many people get headaches. They are doing something that 600 million years of evolution never prepared them for. This is a deep problem, which no amount of technical tweaking can fix."
— Legendary film editor and sound designer Walter Murch on “Why 3D doesn’t work and never will”. He’s got insider’s knowledge, too, beyond that of editing: he helped cut Disney’s Captain EO “4D” film/attraction for Francis Ford Coppola back in the early 1980’s. (Wait, Coppola directed that thing?!)
(via austinkleon)
Megana-ya (Seller of Eyeglasses), by Hokusai, circa 1811-1814, part of a incredibly great collection of health-related Japanese woodblock prints housed at the University of California, San Francisco. Having recently bought a new pair of glasses, I can relate.
(Via Pink Tentacle)
From Dentsu London, Making Future Magic:
We use photographic and animation techniques that were developed to draw moving 3-dimensional typography and objects with an iPad. In dark environments, we play movies on the surface of the iPad that extrude 3-d light forms as they move through the exposure. Multiple exposures with slightly different movies make up the stop-frame animation.
Take that, Picasso.
Another excellent short episode of Radiolab, featuring a conversation with two people I wouldn’t expect to hear on stage together:
Oliver Sacks, the famous neuroscientist and author, can’t recognize faces. Neither can Chuck Close, the great artist known for his enormous paintings of … that’s right, faces.
Oliver and Chuck–both born with the condition known as Face Blindness–have spent their lives decoding who is saying hello to them. You can sit down with either man, talk to him for an hour, and if he sees you again just fifteen minutes later, he will have no idea who you are. (Unless you have a very squeaky voice or happen to be wearing the same odd purple hat.)
If you’re interested in the science of face perception, I stumbled across this relevant paper this week: Cortical Specialization for Face Perception in Humans (pdf) co-authored by Tel Aviv University’s Galit Yovel.
Real-time 3D capture at 60fps using a cheap webcam and simple projected pattern of light points. The structured-light code is open source, looks like a pretty cool project.
(Via Make)
Phil Plait of Bad Astronomy lucidly explains display resolution, clearing up arguments about the iPhone 4’s retinal display technology:
Imagine you see a vehicle coming toward you on the highway from miles away. Is it a motorcycle with one headlight, or a car with two? As the vehicle approaches, the light splits into two, and you see it’s the headlights from a car. But when it was miles away, your eye couldn’t tell if it was one light or two. That’s because at that distance your eye couldn’t resolve the two headlights into two distinct sources of light.
The ability to see two sources very close together is called resolution.
DPI issues aside, the name “retinal display” is awfully confusing given that there’s similar terminology already in use for virtual retinal displays…
For those of you with eyes that aren’t easily categorized as simply “brown”, “blue”, or “hazel”: researchers have written up a new genetic model for human eye color phenotyping, published in PLoS Genetics.
We measured human eye color to hue and saturation values from high-resolution, digital, full-eye photographs of several thousand Dutch Europeans. This quantitative approach, which is extremely cost-effective, portable, and time efficient, revealed that human eye color varies along more dimensions than the one represented by the blue-green-brown categories studied previously. Our work represents the first genome-wide study of quantitative human eye color. We clearly identified 3 new loci, LYST, 17q25.3, TTC3/DSCR9, in contributing to the natural and subtle eye color variation along multiple dimensions, providing new leads towards a more detailed understanding of the genetic basis of human eye color.
(Via Nature)
John Balestrieri is tinkering with generative painting algorithms, trying to produce a better automated “photo -> painting” approach. You can see his works in progress on his tinrocket Flickr stream. (Yes, there are existing Photoshop / Painter filters that do similar things, but this one aims to be closer to making human-like decisions, and no, this isn’t in any way suggestive that machine-generated renderings will replace human artists — didn’t we already get over that in the age of photography?)
Whatever the utility, trying to understand the human hand in art through code is a good way to learn a lot about color theory, construction, and visual perception.
(Via Gurney Journey)
My camera switches over to portrait-mode whenever it sees a painting or a drawing with a face in it. It stays in AUTO mode otherwise.
According to Popular Mechanics: “a chip inside the camera constantly scans the image in its viewfinder for two eyes, a nose, ears and a chin, making out up to 10 faces at a time before you’ve hit the shutter.”
I decided to test my camera—it’s a Canon Powershot SX120—to see what it decides to regard as a face.
Artist James Gurney tests out his point-and-shoot’s facial recognition chip against works of art and illustration. A mixed bag, but a good reminder that this technology is getting better and cheaper (and subtle) all the time.
Magician Marco Tempest demonstrates a portable “magic” augmented reality screen. The system uses a laptop, small projector, a PlayStation Eye camera (presumably with the IR filter popped out?), some IR markers to make the canvas frame corner detection possible, Arduino (?), and openFrameworks-based software developed by Zachary Lieberman. I really love this kind of demo — people on the street (especially kids) intuitively understand what’s going on. This work reminds me a lot of Zack Simpson’s Mine-Control projects, especially with the use of cheap commodity hardware for creating a fun spectacle.
(Via Make)
MyDsReader, Nintendo DS text-to-speech document reading software for the visually impaired. It’s using the Flite synthesis engine designed for embedded devices, implements gesture controls for ease of use and even throws in an integrated email and to-do client. Excellent use of homebrew development.
(Via GameSetWatch)
