Slashdot Mirror
Seeing Around Corners With Dual Photography
An anonymous reader writes "This project (which is part of this year's SIGGRAPH) has absolutely blown my mind. Basically they photograph an object with the photosensor at one point, and the light projector at another, and use the Helmholtz reciprocity algorithm to virtually switch the locations of the camera and projector, showing exactly what the light source "sees"! If that doesn't make sense to you, check out the research page and make sure to watch the 60MB video at the bottom. The playing card trick will leave you speechless!"
I can't wait for this kind of technology to allow more realistic games based off of actual locations, especially in games like SOF and Max Payne...
The exploding server one has already rendered me speechless. Why in the name of god do they do it!
..it would be much easier.
Mirrordot link to the video file.
Wasn't there a scene in Blade Runner where he used something like that?
I find it highly unlikely that many will manage that :0
Brocklesby Park Cricket Club
> and make sure to watch the 60MB video at the bottom.
Yeah, I'm sure Standford can afford the bandwidth, but you're giving ideas to your fellow slashdotters...
(Or maybe not, I can't connect).
I think we are going to need a couple of mirrors of this file or get a torrent setup....
I am trying, I have 26 meg of the file down now, but the speed of my download is definately slowing.
Curiosity was framed; ignorance killed the cat. -- Author unknown
Suppose you shine a projector upwards from the ground.... and take a photo of a girl... what will the technique generate?
Online backup with Mozy, sounds like Ozzie, but more!
Quick, shine a light into your monitor and take a picture. Then use their software to capture an image of their exploding server!
This page was slashdotted before the story went public. Sigh.
Martin
Where does seeing around corners come in?
isn't this just the same in principle as ray tracing? or am I missing something
...is the ./ effect from downloading a 60MB file.
-Mr. Fusion
A 60MB video? Methinks the submitter may be a Stanford dropout with a grudge.
I think, therefore I am. I think?
Yeah, um, hey! April 1st was a bit ago...
Anyone please mirror the movie?
J.
You're only jealous cos the little penguins are talking to me.
make sure to watch the 60MB video at the bottom
What video? I can't even access the webpage.
Need a color? Try 100 random colors
It only took five minutes to kill the server. That has to be some kind of record.
Dual Photography
Abstract
We present a novel photographic technique called dual photography, which exploits Helmholtz reciprocity to interchange the lights and cameras in a scene. With a video projector providing structured illumination, reciprocity permits us to generate pictures from the viewpoint of the projector, even though no camera was present at that location. The technique is completely image-based, requiring no knowledge of scene geometry or surface properties, and by its nature automatically includes all transport paths, including shadows, interreflections and caustics. In its simplest form, the technique can be used to take photographs without a camera; we demonstrate this by capturing a photograph using a projector and a photo-resistor. If the photo-resistor is replaced by a camera, we can produce a 4D dataset that allows for relighting with 2D incident illumination. Using an array of cameras we can produce a 6D slice of the 8D reflectance field that allows for relighting with arbitrary light fields. Since an array of cameras can operate in parallel without interference, whereas an array of light sources cannot, dual photography is fundamentally a more efficient way to capture such a 6D dataset than a system based on multiple projectors and one camera. As an example, we show how dual photography can be used to capture and relight scenes.
(a) Conventional photograph of a scene, illuminated by a projector with all its pixels turned on. (b) After measuring the light transport between the projector and the camera using structured illumination, our technique is able to synthesize a photorealistic image from the point of view of the projector. This image has the resolution of the projector and is illuminated by a light source at the position of the camera. The technique can capture subtle illumination effects such as caustics and self-shadowing. Note, for example, how the glass bottle in the primal image (a) appears as the caustic in the dual image (b) and vice-versa. Because we have determined the complete light transport between the projector and camera, it is easy to relight the dual image using a synthetic light source (c) or a light modified by a matte captured later by the same camera (d).
Seeing that R-ing the F-ing A is an impossibility for me right now, due to an inexcuseable lack of .torrent or google cache link, I'll just post some outright fabrications about it's content.
This technology proves that there was a third gunman on the grassy knoll. This technique is like what they did in the Matrix, except "backwards." With this technology, any man can find the g-spot. When you look at the videos upside down, you can see into the past.
Doesn't it seem a little funny that we need a mirror to get a look at this movie?
The little guy just ain't getting it, is he?
With a video projector providing structured illumination, reciprocity permits us to generate pictures from the viewpoint of the projector, even though no camera was present at that location.
Other than using electrons instead of light, that's how a scanning electron microscope works. An object is scanned (raster scan) and one or more sensors near the target pick up the reflections to generate an image. In the SEM the image appears as viewed from the scanning electron beam source.
In the optical one mentioned in the article, the light source is a raster scanning projector which lights a target. The image is produced from photodiodes picking up reflected light.
These two systems are very much alike. One uses photons and the other electrons. The end image is generated the same way.
The truth shall set you free!
Note: I haven't read the paper yet, but it is downloading.
It seems like this might have some military applications as a result. Imagine sticking a photo-resistor array under a door or through a window and then getting "viewpoints" from any of the lights in the room. Could aid in target aquisition and elimination.
Not sure how well it works for something like that, but this is a rather impressive (at least to me) research project.
There are only 10 kinds of people in this world... those who understand binary and those who don't
I always wonder what are the costs associated with a website onces its /.ed? I wonder how many small sites we have taken out and also how much bandwith we spike. Once this is figured out someone should sell /. insurance.
21 8E 7E DF 0F 86 C4 03 1D 30 74 55 0F 16 D0 1E
Even the mirrordot mirror is very slow now.
see a Text Widget
OK, the stitching together is harder in the latter case, maybe an awful lot harder, but unless I have missed something really big it is a statement of the nearly obvious. Anyone remember the scanning electron microscope? By collecting backscattered electrons, you could use one of those to see around (very small) corners.
Or I am completely wrong and this is something very much more clever. If so, please can someone explain?
Panurge has posted for the last time. Thanks for the positive moderations.
They make the point that if you illuminate an object with a projector, you can get the image with a photocell. That's because the projector scans the image with a light beam. If you know when you see the reflection, you know where the light beam was when it reflected because you have prior knowledge of the scanning pattern. That technique has been used forever. It's like the flying spot scanners that predate camera tubes.
The 3D part is obtained when you offset the detector and the projector. If I look at a particular point on an object and scan the object with a beam of light, I can get the distance between me and the object as a function of the scanning angle.
All these people are doing, are using the first barcode technique to, take a picture of the scene. Instead of using a laser, an animation of a moving white dot is sent to the projector. The Camera, is then treated like a light sensor, for each point in the animation, the camera is queried for the brightness of the perhaps, brightest dot in it's field of view. Gradually the picture is built up, pixel by pixel, untill, finally a picture is formed in memory. This picture would be from the perspective of the projector.
"And then thus spake the Lord, 'Verily I say unto you, HOAX!'"
Is something burning?
Oh, it's my karma.
Maybe we could use that mirror to get a different viewpoint of the article?
Well, I've begun the download for this video, and seeing as how mirrordot is being slashdotted, I have only downloaded about 20 megs out of the 60 meg file, with an ETA of about 25 minutes. At any rate, I've put the mirror up linking to the file that's being created -- and in 25 minutes that file will be complete, until then it'll be some percentage of the total.
Enjoy.
Yeah, right. You expect me to believe there's a so-called 'spackler' somewhere out there? I can't see it. I've never directly observed it. I'm supposed to just accept its existance on faith, based on a few secondary phenomena like a slashdot posting?? Let me be the first to call HOAX!
Whence? Hence. Whither? Thither.
Goldfingers solution was much sexier.
There is nothing so silly as other peoples traditions, and nothing so sacred as our own.
I totally lack any scientific degrees, but this technique looks an awful lot like raytracing in reverse(or even real world application of algebra)... the projector is necessary to help map the way certain areas of the subject react to light based on the surface quality, and using pixel level illumination from the projector recreates the camera... FUCKING BRILLIANT.
this technique works because of the lcd/dlp array in a projector, but i wonder if it can be reproduced if the light source is already a pinpoint(chrismas light, or very small bulb). what happens when the light source is very broad, like that of a computer monitor/ TV? i wonder if this technique could also be used to extrapolate what someone is watching/reading/viewing on screen? taking another stab from a raytracing perspective, i wonder if an environment could be revealed thru image analysis, aka reverse-HDRI?
hats off to the dually photo boys of stanford and cornell... keep up the cool work.
three can keep a secret, if two are dead - benjamin franklin
and why dont we have it?
-- 'The' Lord and Master Bitman On High, Master Of All
Someday soon, the owners of a site that gets slashdotted are going to sue faster than CmdrTaco can say "tort reform". It's irresponsible to post, unedited, an article suggesting readers download a 60mb movie without first making some effort to mirror/torrent the file and/or site.
Maybe we should set up this camera technique. We pretend like we're gonna download the file, stick a light source on the side, and TRICK it into getting a copy of the file! ha!
Anyone know what the dept line is referring to?
Media that can be recorded and distributed can be recorded and distributed.
-kfg
Only the first part for now :
a rt1.mp4.torrent
http://dload.digitalriviera.com/DualPhotography-p
Second part in 30 minutes !
First torrent I host, I hope it's ok.
where can I find a mirror to the video (other than the mirrordot site)
or mayeb can somebody send it to me by email? now that I have 2 gigs on gmail i can handle it.
just joking, gmail can't handle attachments larger than 10 megs
but maybe you can cut the whole stuff and send them by email in six pieces.
Send them to cuzuco[at]gmail{dot}com (let's see if you can slashdot my gmail acocunt)
Whoa. UVa's outbound connection just got crushed -- I can help someone create a torrent, but my mirror can't sustain this. I've already dished out a couple gigs of data -- and the server basically dropped.
Seriously, I was downloading of of the UVA Residence conection from from www.people.virginia.edu at nearly a megabyte a second, and I can't access the server any longer -- even my access to our mail server and network file storage was getting slowed.. Nasty phone calls will come from this.
Someone would be much loved if they created a torrent for this -- and if that somebody needs fast access to this file, just send an e-mail to pg8p At virginia magicdotofdoom edu, and I will give you direct access to the file so you can download it quickly and get the torrent up.
Sorry amigos -- a few hundred KB per sec is okay, but megabytes per second of bandwidth usage is not going to fly. A torrent would work magic here.
wanna remove banner ads. modify your host file, add 127.0.0.1 adservername.domain.tld
A good start is this file
yeah, I know it is off topic. I got Karma to burn
Don't fight for your country, if your country does not fight for you.
Because what was a camera becomes the only light source, what you're trying to see will be in near-complete shadow.
Your torrent is working great - thanks! Only 12 peers but I'm getting great speed.
I'm a big tall mofo.
What kind of codecs or player do you need to view this file?
Reminds me of this Slashdot article on an "optical TEMPEST" device to "eavesdrop" on the display put out by a CRT monitor. This has been around for a long time by picking up electromagnetic emissions, but this method used the light from the CRT itself, as reflected off of walls and such: a photomultiplier tube and a fast digitizer allows you to reconstruct the image from seeing how the light in the room very quickly goes from light to dark and back as individual pixes are painted on the CRT, given a knowledge of the CRT scan rate and resolution.
Was I the only one that saw that as:
Seeing Around Corners With Dual Pornography.
I need more coffee.
Well, there's spam egg sausage and spam, that's not got much spam in it.
Don't blame their webserver/fileserver for not being able to see the movie they raved about.
It is the laziness and irresponsibility of the slashdot editors to not provide a bittorrent link.
I am disgusted that slashdot raves about a site/file/mpeg then DDOSs
it so that nobody sees it. This is particularly bad when a hobbyist site is crushed.
Mod me into oblivion, I don't care.
I'll throw my poor server into the flames
http://www.whaleweb.net/mirror.html
2x 1.1Mbit DSL lines + PacketShaper
*ducks behind table*
1. Reverse transformation for any interesting case (note that no places are actually revealed on their example!) will always be close to singular, that means in practice that your noises (due to raster, finite precision, and just measurement error) will eat any signal in result.
2. You should know not only amplitude, but *phase* of the source signal, that means for light that you have to use coherent light source and utilize interference on the receiver.
1 + 2 = holography, so what is new?
(Read the article, but still downloading the movie)
Another mirror here. No guarantees as to how long it will stay up; if it pushes me close to my monthly bandwidth limit I'll kill it...
> extrapolate what someone is watching/reading/viewing on screen?
h tml
Something like this?
http://www.cl.cam.ac.uk/~mgk25/emsec/optical-faq.
Voltara
I haven't read TFA yet, but how involved is the maths behind that project? Is it simple trigonometry? In particular: Is it possible to build such a setup at home from consumer LCD/DLP projectors?
;)
Could I image my hot neighbour's bedroom and see her make out in her bed from the perspective of her bedroom's ceiling light ? That would be killer
--- Eat my sig.
That would be the funniest thing ever on Teen Girl Squad.
It is already possible and demonstrated to view what is on a CRT by analyzing the brightness changes of the surrounding room through a telescope.
http://graphics.stanford.edu.nyud.net:8090/papers/ dual_photography/
Come on kids, coralcache is the way to go. no more direct linking to servers that go down quicker than, well, you know.
Man.... UVA Blows.
<high-level position here>
<name of stupid small company here>
BitTorrent file here. http://bisqwit.iki.fi/torrents/DualPhotography.mp4 .torrent
http://www.nrsmith.me.uk/~neill/temp/DualPhotograp hy.mp4
Could I image my hot neighbour's bedroom and see her make out in her bed from the perspective of her bedroom's ceiling light ? That would be killer ;)
No, that would be stalker. Still pretty bad, but not quite up to murder.
sudo ergo sum
now mod this up
[Fuck Beta]
o0t!
Yes.
Seems to me that the 'powers that be' tend to frown
/. for?
:)
on people copying con....
WTF am I wasting my time posting drivel on
Face it... None of you care what I think LOL
Several projects at SIGGRAPH last year addressed the question of what you could do with a planar array of cameras. You could consider this the natural extrension of stereoscopy (two cameras) or a cost-effective approximation of real-time holography. Some of this research is motivated by that commodity digital cameras and real time digital image processing computers can be bought at low prices, and assembled like RAID disk arrays or cluster computers.
Applications of these arrays included several kinds of real-time 3D TV (without silly glasses). The Stanford group pushed "conformal imaging", that is a cube of image planes at various depths and all viewpoints. This has the effect of looking around corners and through keyholes: if there a path for light to get through, you can probably extract a complete image. This does involve some mathematical massaging of multiple-camera images. Cheap Graphical Processing Units (GPU) from game machines can be reprogrammed to process images in real-time.
http://tnb.aau.dk/projekt/nat_d321/DualPhotography .mp4
Uni-POWER!
God is NOT a hoax. You had better ask for forgiveness for your blasphemous comment.
I will, in the mean time, here's another mirror
Does anyone remember those optical crystals that were grown about 20 years ago that would essentially do this?
IIRC, a description was that if you held one a couple of feet in front of your eyes, very steady, it would create a virtual image of its surroundings, including around corners and behind things. How steady you had to hold it and the speed the image fell into place was dependent on the general level of illumination.
I read about it in one of the trade magazines at the time and you could order small samples (maybe a quarter inch cube) for something like $40. I did try to order one but my check was returned with a letter stating that sales outside the government were halted.
I've always been curious what those things were and what happened to them.
Is that if you can do this in semi-realtime you can guesstimate the location of major directional lights in a real-world photograph and see if what comes out makes any sense. There might be some way to automate the process using some kind of simple model of what a "realistic" output image should look like.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
Gosh, how fascinating. Now compare this to a *really cool* imaging technique, like using an x-ray beam and an array of photodiodes to detect the scatter patterns as the beam passes through a human body, then calculate an image of the actual bones and organs inside. It's called Computed Axial Tomography or a CAT scan. And if you want something *realy really* cool, check out the technique that uses a magnetic field gradient to delay the re-emission of photons from an RF pulse, and then calculates the position of molecules in a body from their RF scinillations. Its called Magnetic Resonance Imaging or MRI. Somwhow I think the images they produce are slightly more profound that scanning the back of a playing card. Consider yourselves offcially Harumphed.
"Sic Semper Path of Least Resistance"
http://ftp.acc.umu.se/mirror/media/DualPhotography /DualPhotography.mp4
That's a neat hack, but the basic idea is pretty simple: you scan a dot of light across a surface and see how much gets reflected from it: if a lot of light gets reflected, the spot the light was shining on was bright, otherwise it was dark.
Impressive, but mostly crap. They don't really have a diffuse light source, they're projecting a focused probe beam. So obviously, yes, you can figure out the color of what the beam is hitting, and from the beam's point of view. Big whoop. What you can't do is do this to any scene with any depth to it. And you don't get very good resolution. Not until someone comes out with a white-light laser beam. What we used to call a Polish invention.
Apple Quicktime if you're on Windows or Apple, as the other poster mentioned MPlayer for Linux should be able to also.
The coolest thing to me is the glass Coke bottle. Of course it's simple geometry, but I just love the way the shadow in the primal photo becomes the bottle in the dual photo and vice versa. Check out the positions of each in both photos against the book behind them. That just shakes my drawers. Was anyone else expected Penn to pop into the video with the three of clubs and say "Is this your card?" P.S. Sorry for the high-tech post full of jargon....
"Even for Slashdot, that was a very obscure reference!" - Anonymous Coward
Can anyone identify what codecs are used in that video? Mine just refuses to play.
Or imagine sticking a miniaturised camera under a door or through a window and then getting a clear viewpoint of the room!
ok, from what i can find in the mirror of the article, and from my own imagination:
:)
you have a monitor & a 1 pixel photo diode. there is no other light in the room.
on the monitor only the left&uppermost pixel is white, rest is black. the photo diode measures the light intensity(spatial resolution 1 pixel, but it does have a resolution in time.) and from that you get a transfer funcion from upperleft pixel to photo-diode. you then turn the pixel off, waite for the photo diode to measure "nothing" then put the next pixel on. measure the transfer function from that pixel...etc etc. in the end you have all these transfer functions from pixels to the photo-diode.
you just assume they are the same as the transfer functions from a light source at the place of the diode, to a light-sensor at the place of the pixel on the screen. all together they will make an image seen from the monitor viewpoint, lit by the photo-diode.
it might also work with just random images on screen if you exactly know these images and the response to them. in theorie if you waite long enough it should be possible to calculate the responses back to individual pixels...with just 1 photo diode.....omg.....all computers might secretly be photographing users all around the world....i will so never jerk off again in front of my monitor
in response to people asking about neighbours house, etc...you will get the image as seen through their 1 pixel lightbulb....not really interesting....unless their room is lit by cable TV......omg again..../me starts programming now.
Shrug. They post a 60MB file for the public, they should expect the public to come and download it.
It's up to them to restrict access, to throttle bandwidth or to deal with a server outage.
I have no sympathy, and even though it may be irresponsible to post an article suggesting readers download a 60MB movie, it's even more irresponsible to violate copyright by mirroring or providing a torrent for the file.
~cederic
Here is a torrent that might be useful.
Gosh, I can't believe you guys are IMPRESSED by this. I mean, look at how calmly I spout off the names of several unrelated technologies. I've even taken the time to do a quick Google search on their names in order to copy and paste large words! Can you seriously be impressed by anything that doesn't measure up to my standards of technological wonder? (The self-important nerds who post about how unimpressive this is aren't impressing any of us who can appreciate ingenuity and hard work)
Magnet link for Decentralized Tracker (requires Azureus BitTorrent Client), DualPhotography.mp4:
magnet:xturnbtihJJG7QKRLISZVB24YFXS7YPYHVGEBPSTZ
How the hell does mirroring a file "violate copyright" -- in a way that merely downloading it does not?
This torrent seems to be working.
on how long before this technology shows up in an episode of CSI?
OK, the technique isn't really new as highlighted by some as it's used with x-rays, electrons in some other things. But I think the important part of the paper/video is that they developed an algorithm to speed up the process by finding non overlapping pixels to reduce the steps needed to capture the picture. It's not new, but it's an enhancement.
To analyze the projector's image quickly, they need to control the projector, sampling its pixels' images to factor out redundant pixels. Trojan-horse programs which control the projector probably won't trigger current antivirus SW. Any screen can now spy on you, if a camera can only get a glimpse of its reflected light. Combined with laser microphones, you're on candid camera! Beware untrusted screensavers!
--
make install -not war
For what it is worth, here's a torrent.
There is a torrent here.
Video and PDF on fast link based in the US. I've survived slashdotting before, go for it ;-)
Here is a working torrent.
Because mirrordot can't handle it either? Maybe this torrent will work?
reminds me of the camera thingy used by Deckard in BladeRunner. That was awesome ! ..seemed like it had infinite resolution !
now i gotta look for a projector, a camera and a cpu processing the images in realtime at my next poker game =\
our new overlords, who can now see us around corners.
6D slice of the 8D reflectance
Imagine... oh, wait.
There you are, staring at me again.
Is it just me, or is the image shown on the page a rendered image?
The teapot kind of gives it away.... I also have the book in the picture, and I've seen the model of that book in some sample renderings out there. Additionally, when's the last time you saw a REAL coke bottle, outside of 3D renderings... or the ancient teddy bear. All are classic examples of 3D meshes often used to demonstrate various 3D techniques.
If, for the sake of the argument, this is rendered (I believe this to about 99% certainty), then the demonstration, perhaps still valid, is demonstrated under perfect conditions, as opposed to a real-world application.
Also, if it's rendered, who's to say the results and the paper itself are nothing more than academic huxterism?
I'm not trying to troll here, just trying to understand the conditions and import of this whole thing, beyond the slashdotting of the server there.
Here we are still pushing the boundaries of what computer graphics can do for us. The biggest thing for me is rendering reality in ways that provides new insight. That's graphics in a nutshell and Siggraph is where it's all showcased each year.
For anyone who thinks math is boring, consider this field. You get to put your math to work in a very revealing way. (Makes me want to go back and study.)
Today we have these powerful computers that are just so damn cheap. Graphics engines can display things that were not even on the map as a kid. Middle Schoolers today can begin to explore potent tech for only the cost of a machine to run their ideas on. How cool is that.
For anyone who thinks OSS is a waste of time, consider the above and know you are going to see something very interesting because somebody somewhere was just able to compute for the hell of it. And how cool is that huh?
Sorry to just ramble. I just like this stuff and feel it's worth pointing it out once in a while, that's all.
Ever notice how much more OSS is involved these days? Used to be SGI machines, now it's win32 and OSS driving a lot of this stuff. (Don't know about the Mac, sorry guys I want one too!)
Blogging because I can...
Remember the scene in Blade Runner where Deckard is zooming in on the photograph and seems to get image out of no image... seemingly passing through a door frame, changing perspective... It seemed like total fiction until now...
That's all great and all, but when I can use this with 3dsm and Maya?
I didn't understand half of what they said but sounded good.. ya, the playing card trick was very cool. Can I use this technology though ? I'm thinking maybe it could be modified to peek through a woman's clothes.. X-ray Vision, finally?!
You maniacs, you did it, you really did it. You went and blew it up. Killed its bandwidth. Shut the server down.
Any server mentioned on Slashdot better be frickin' Piranha Proof because its like sticking a computer made of meat into a pool of hungry Piranha.
Maybe NEXT week I'll get to see it... damn you, damn you all to hell!
I was imagining upskirt cam technology rapidly advancing up until i read your post..
Is this anything like the Nintendo light guns that allow you to video-hunt ducks?
Look at the first two pictures, they are simply morphed, ie. the viewpoint did _not_ change, so there is no looking around corners.
In the event I'm wrong: dude, you really need to spend more time in the same physical room as other living people.
Dewey, what part of this looks like authorities should be involved?
..the camera projects on YOU!
Hexy - a strategy game for iPhone/iPod Touch
The link that the parent has posted is *exactly* the same link that appears in TFA.
I wonder how this argorithm replaces lost information. If you look at the pictures, the names of the authors in the textbook dont change from the two persepectives, i.e. the shadowed name remains that way. Seems like a fortunate coincidence.
(I have only seen the pictures, not the video.)
please change me. - sig
One aspect of Video phones and other video-chat technologies is that both parties can never look into each others "eyes" simultaneously.
Your eyes never meet, as they do in a physical one-on-one conversation because the camera and video display are at least a few inches apart.
I wonder if dual photography could be used to create the illusion of having the "camera" in the middle of the display device so you could actually "lock eyes" during a conversation.
I guess you'd need a pretty bright display device...
There is no new data in the projected image from the original. Note the teddy-bear's left chin in image (b). It should not be in shadows because it is being viewed straight on from the projector. Also note that you cannot see any more of the text or picture behind the bottles than what's already shown in the first image. So you can't see around corners at all. If the data wasn't in the first image, its not going to be in the projected image either.
This sounds an awful lot like the flying-spot Nipkow disk scanning method used for television in the late 1920s and early 1930s. In the television image, the sources of light appear to be where the phototubes are, and the perspective is from the light source.
Hey, speaking of TVs and cameras, you know how videoconferencing has always been a little awkward because it's difficult for both parties to simultaneously make eye contact? If you look at the image on the screen you will appear to the other person as if you're looking away from the screen (i.e. not making eye contact with them), because the camera is recording you from above the screen (or below, or to the side)? Wouldn't this technique be able to morph the onscreen image so each person appears to be looking directly out of the screen, even though the camera is still recording you from a higher angle? It would be as if the camera is in the center of the screen, which would be the only other way to make it appear as if you were looking directly at the viewer on the other end. Simulated eye-contact by exchanging the position of the light source (TV) and the camera in the projected image.
Or can they do this already somehow?
With my new research, I've been able to interpolate the entirety of the universe from a piece of fairy cake!
Awesome furniture, accessories and cabinetry in Santa Rosa, CA: http://humanity-home.com/
If only a screen and a photodiode are necessary to capture images, how difficult will it be to hack a normal TV (with a photodiode in the form of an IR-sensor) into a camera without *any* outside changes (or even complete software-based in newer tv's)? or even into a 'telescreen'-like device? Or what about adding one $0.10 photodiode to a laptop and have an integrated webcam?
Also, as an comment above points out, you would be much better off with a CRT projector than an LCD projector.
Use this method to see the side of a planet that we have never seen by switching places with the Sun(projector)? Nice!
...and will be the McGuffin in next weeks episode of CSI.
i am endorsed for the carrying of dangerous goods, please be giving me your depleted uranium
So instead of relying merely on the perspective of the Zapruder film, we can get what the sun saw over the wall on the grassy knoll. You can get the view from the book depository and even JFK's point of view if you like (multiple projectors). Of course the film is old and slightly blurred, and it would involve... hey! who's there! Hey, you can't take my compu, You're hurting my arm sir! YOU"RE HURTING MY ARM SIR! HHHhhheeeeeellllppppp......
I just tested it out with my light-brite and three cabbage patch dolls.
Storm
Strange that noone has mentioned the similarity with that tool :)
in Blade Runner. Sci-fi is becoming reality
I sent them an email note and now they have a torrent posted on the website.
Where you take a picture to the glass, and if it is splitted, you can watch the missing part using the rest of the picture, like window. But it requires laser and time and immobility of the target during "photo session".
However, it seems like new technology may increase the number of wannabe photographers, producing superb pictures... And imagine, what delicious porn we'll see in 4D! And, of course, tons of spam, offering that porn... Time to update SpamAsassin with that new terms...
The Shadow knows!
There is an error in the rendering of the view from the light source.
Naturally, the view from a viewer is the most familiar to us and will be assumed to be the most accurate presentation of reality. In other words, the camera view is assumed to be correct. Now ask yourself, what should the view from the light source look like????
If there is only a handful of point sources of light the resulting lit image is pretty simple. Opaque or almost opaque things block light and make shadows. Ha ha ha ha ha! Reflections and lens cause more complications.
The upshot is the bottle's shadow when seen from the light source ought to be right behind the bottle. Instead the rendering shows the bottle's shadow off to the right side.
Further problems: what the bottle blocks from the camera view (perhaps a secret message on the book or a crack in the bottle) should come into view as one looks from the light source. Instead the rendering of the view from the light only becomes a morph of the view from the camera.
The claims of the research are tantamount to taking a photo of the ground in a total eclipse and being able to deduce the dark side of the moon.
Know your pads. One time pad: good for cryptography. Two timing pad: where to take your mistress.
Would this work for video conferencing applications to make it apear that the users are both looking at the camera?
I always wondered if the invisibility trick would involve a mesh of cameras and light sources. If you could map an arriving photon on one side, and transfer, or emit it somewhere else, you could do basic invisibility. If you combined emmiters and detectors in the orthagonal way they mention, with a strict backview angle; invisibility is easy. The limit would be resolution and cpu speed for updates. Your interlacing would have to be 2x above your acceptable tolerance. Under strict conditions is one case. But I always wondered in that scenario, how you could possibly adaptively map a smooth spherical exploration around the subject that is 'veiled'. Maybe it is Helmholtz reciprocity. But in the application of invisibility, perhaps involving many more dimensions.
Maybe someone will invent a dual photon gate/sensor combining emitter and sensor.