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Wireless Networking Idle

Light Painting Wi-Fi 65

dostojevski78 writes "Some Norwegian art students built this gizmo to visualize wi-fi signal strength in the city streets. The result is simply beautiful. Who said technology can't be aesthetically pleasing?"

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Light Painting Wi-Fi

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  • I know who. (Score:5, Funny)

    by Siberwulf ( 921893 ) on Wednesday March 16, 2011 @03:04PM (#35507212)
    Who said technology can't be aesthetically pleasing?

    Pretty sure it was Roger Ebert.
    • by blair1q ( 305137 )

      No, he just said video games aren't art, and he's right, and the video game industry agrees with him.

      They may include things that are artistic, but they aren't art.

      Although, having played a little with the Katamari Damacy [kathack.com] plugin, the field may be changing.

      • Let's not muddy up humor with fact, mmkay? ;)
        • Quick. Arrest the guy and seize the equipment.

          We need to check whether he's capturing signal strength or just appearing to do so while capturing and storing packets from all these networks to datamine for user names and passwords later, just like Google was!

      • by Lundse ( 1036754 )

        No, he just said video games aren't art, and he's right...


        • also heavy rain. Also the argument is stupid anyway. Art really is the creation of anything with any intent behind it. The artistic value of different creations is subjective, the fact that it is art is not. The idea of video games not being art is essentially anti functional art. A painting has no function aside from being a vessel for the intentions behind the art. A cathedral, aside from being architecturally beautiful also functions as a space to be in to be used by people. A game is a creation that is
      • Silly rabbit. There is no such thing as art.

      • by Anonymous Coward

        No, he just said video games aren't art, and he's right, and the video game industry agrees with him.

        Ridiculous. No reasonable definition of art can include books, paintings, movies, and poems, but exclude video games. I think people get confused because (a) they're Luddites, or (b) the vast majority of video games are terrible art.

      • you might as well say thought does not exist.

        art is one of those things that can not be defined, unless you wish to be proven wrong.

        art is different to everybody. saying one person's art is not art is like saying their god is not god. it means nothing.

    • This is art. It's useless, but cool looking. If it was useful it would be engineering.

  • by GodfatherofSoul ( 174979 ) on Wednesday March 16, 2011 @03:11PM (#35507288)

    Knowing the difference in signal strength along 100 feet of sidewalk is pretty useless. Just throwing out an idea, I think it would be neat to use a NASA-ish artificially colored satellite view of a city. At different points; record say three different metrics; secured network strength, open network strength, and say number of networks. Assign each an RGB component and color your maps that way. You'd be able to quickly look at a map and determine based on color and intensity the approximate characteristics of WIFI all over a map.

    • They're artsy types. Having it be useful would defile their hipster image :p

      I like the technology, but to me it amounts to nothing but "Heh, cool concept." and I dont care beyond that.

      OpenSignal has a map like what you describe for cell coverage. Installing the free app lets you contribute data too :)
      Not sure if it has wifi?

      • OpenSignal shows no coverage anywhere near my house for any carrier, and the nearest AT&T signal is several counties away.

        I'd download their app to contribute data, but I don't have an Android and they don't support anything else. It looks like the one guy in my state who downloaded it for his droid used it 3-4 times, tops.

        Neat idea, though.

      • but to me it amounts to nothing but "Heh, cool concept." and I dont care beyond that.

        I don't mean to be snarky but I'm sure they would say the same thing about half the stuff you do and consider "useful." Not everything has to be a tool. (I'll refrain from using that sentence to set up a snide remark) Some things can just be for enjoyment... e.g. art. I thought it was one of the coolest photographs I've seen in awhile. It's particularly interesting to people who have both an interest in photography and technology.

        • If you dont see that the "useful" comment was humor, you need to have your fun-o-meter checked ;)

          Not everything has to be useful, that was the point of the comment. It has long been argued that if something has a purpose other than being art, then it cannot be art.

          • Sorry - I probably should have my fun-o-meter checked. It seems to have been stuck on zero ever since this semester started. (personally, I blame Dynamics)

            • Ah, the joy of college...

              Glad I'm done... There is that pesky thing called "work" that sneaks in when that happens though...

    • Just throwing out an idea, I think it would be neat to use a NASA-ish artificially colored satellite view of a city. At different points; record say three different metrics; secured network strength, open network strength, and say number of networks. Assign each an RGB component and color your maps that way. You'd be able to quickly look at a map and determine based on color and intensity the approximate characteristics of WIFI all over a map.

      Very cool idea. You could do this with the data that WiFiFoFum [aspecto-software.com] gathers. It logs all the APs you drive or walk past and then exports to a KML file that Google Earth overlays onto the satellite images. I'm sure someone out there could convert the information into colors pretty easily since all the information that you suggested is included in the file. I managed to get the app just before Apple pulled it off the shelf and its bad ass.

    • by ebs16 ( 1069862 )
      Check out WiGLE: http://wigle.net/ [wigle.net]
      • Wigle.net is the original, largest and best open database of wireless networks. People should check it out and ignore all the proprietary halfassed crap that gets dumped on topics like this all the time. WiFiFoFum? WiFiFoFuckOff. Wigle's Java client is open source, and they have an Android client too.
    • I did something a bit like that before by walking around with a laptop, pair of headphones, and a clipboard (I didn't have a GPS unit at the time, so I marked each intersection's corner-points as I passed them and used interpolation; the laptop played a musical sequence through the earphones to give me the data to mark on the clipboard). If I find the map images I made, I'll link to them... of course, I was tracking the number of networks, since that was a better number to use in a highly-network universit

      • Oh, I do remember that the network name was plotted in roughly the centerpoint of the area where the network was available... that just came back to me.

    • by adamdoyle ( 1665063 ) on Wednesday March 16, 2011 @03:42PM (#35507648)

      I would actually argue that while it may not be useful per se, it is definitely interesting to see how geography affects WIFI signal. I would really like to see a 3d version of this where instead of being, say, 30 rows by 1 column, being 30 rows by 30 columns so that you could have a 3d grid of voxels(?) where height is proportional to signal strength. It would still be artistic yet would paint a better picture of the affects of geography/terrain/building materials on WIFI strength.

      (I do kindof wonder how long the signal strength meter takes to update and if it's enough for this to actually correlate accurately to the current position)

      • *effects of geography (not "affects" - my bad)

      • It still wouldn't be a good representation, as the measurement isn't taken from multiple points on the row, it's a single point, and the height of the graph equals the signal strength of that single point, so you're not getting a 3d map, but a 2d map as it's a sensor strapped to his back that's taking the measurement.

        If you want a real 3d map of wireless connectivity, you'd need to take 3 - 5 measurements per spot at different heights, and have very accurate gps location data per measurement, and via comput

        • It would be 3d because its time lapsed. By moving about in a 3d space, samples within a 3d space would be projected into a single frame of reference (the picture).

        • Dimension One: position on x-axis
          Dimension Two: position on y-axis
          Dimension Three: signal strength

          The dimensions don't have to be of the same form to be considered three-dimensional. People make the third dimension something non-positional all the time on 3D graphs.

          • I understand that it's only a 2d scalar field, if that's what you're saying, but it's still a 3d plot. It just only paints us a picture of the signal strength of a points on a 2d plane. It would still be better than the current implementation of a 2d scalar field of a one-dimensional line.

            Alternatively, though, I guess they could have full-color lights and strength meters next to every light and change colors based on signal strength at every single point. That would be a 3d plot of a 3d scalar field.

    • I thought the images were pretty cool looking. But for me, they never really seemed to capture an image which really showed its potential. They needed to position the camera such that it was an 3D isometric view and take pictures around interesting geography and buildings such that you can get a sense of how the geography and distance are playing a significant role in the observed signal strength.

      To some degree you could see this. For example, when they walked past windows you could see the strength rise. W

      • The more I think about it, the more it seems that 3D would get pretty expensive and time consuming. (despite how awesome it would be)

        Also, I just noticed where they did two "trials" along the same path and the output was completely different. That suggests that either the signal measuring device is too slow to be accurate or that the field is constantly changing. I suppose since data is sent in packets and that networks probably only broadcast their presence in bursts that it's the latter, making this wh

        • I just saw your reply to my comment right after I posted this. Someone mentioned it in the comments of the linked article as well. I'm sure at some point someone somewhere will build one.

        • Link to the two trials with different output:
          http://www.flickr.com/photos/timo/5481044733/in/photostream/lightbox/ [flickr.com]
          http://www.flickr.com/photos/timo/5481047867/in/photostream/lightbox/ [flickr.com]

          They follow the exact same path and yet the graph of bars are completely different. Almost opposite, really... I obviously expected there to be some variance, but these are not even close.

          • Maybe they could have the person pause his or her movement at every "measurement" long enough to sample the data so that they could just flash up the maximum signal strength over a period of time. They'd just have to make some simple adjustments to their shutter speed and aperture on the camera to allow for the longer time but I think it would be a little more accurate. Obviously that would involve a significant code rewrite, though.

  • Slow news day? (Score:1, Insightful)

    by pahles ( 701275 )

    I saw this already in February on another site...

    The effect is cool however!

    • by blair1q ( 305137 )

      Super-slow. Must not be any nuclear reactors threatening to explode anywhere on the planet.

  • by Anonymous Coward

    Look at the unnecessary source code commenting at 01:56! LOL!

    • Common practice in academia.
      I dont see the problem with making sure the constants are well documented.

      I'd link you a trollface but I cant be arsed :p

  • Or at least my Wi-Fi network is. They used my building about two minutes in :)

    • by mmj638 ( 905944 )

      It would be cool if they displayed not only signal strength, but the WPA passphrase too.

  • I'd like a device roughly the size of a key fob or an old simple (not text) pager (anybody remember those?) that would have GSM, CDMA, and 802.11n circuitry in it, that would simply tell me based on standing where I presently am, how strong the various mobile wireless signals are.

    I could stand in the place where I am...now face north, think about direction, wonder why I have no signal now.
  • More bars, in more places. That's wifi.
  • I didn't understand when they showed overlaps in the signal. The picture would show a certain "level" then a second pic of the same area would then show a completely different level. Did they switch networks? I initially assumed they were measuring the signal of all the wifi in the area. I must have missed that part and it left me wondering how accurate the whole production was.
    • by audunr ( 906697 )
      I saw this on tv the other day, they were talking about how the signal went down and then up as they moved between areas with different wireless networks. So it must be the strength of all networks.
  • I was wondering how best to take long exposure images and not have the dark areas be over-exposed a while ago and I just came across this light-painting plugin for the video editor KDEnlive: http://www.kdenlive.org/users/granjow/light-graffiti-2nd [kdenlive.org] Their plugin demo video is pretty neat and I would assume could be applied to video that has already been filmed and properly modified to enhance the brighter areas.

  • i imagine a set of 'wifi-vision goggles' or, more generally, non-visible electro-magnetic spectrum goggles. when you look through the goggles, you see the normal world with overlays of different colors representing different parts of the non-visible (to humans) electromagnetic spectrum, with the brightness proportional to the signal strength.

    if 3d edge detection is possible, then render a surface as well.

    you could filter individual wifi channels, or filter for other bands such as vhf/uhf television, am/fm

Never worry about theory as long as the machinery does what it's supposed to do. -- R. A. Heinlein