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Transform Cellphones Into a CCTV Swarm

Posted by Zonk on from the now-how-to-interface-your-brain dept.

holy_calamity writes "Swiss researchers have developed java software that has bluetooth-capable camera phones form a distributed camera network. Each phone shares information on visual events with its neighbours and can work out the spatial position of phones around it (pdf). The software will become open source sometime next year, and the creators say it could be used to make a quick and dirty surveillance system. 'The phones currently use the average speed people walk to guess the distances between themselves, based on how long people take to move from one phone's view to another's. In testing, the system determined the distances between each phone with about 95% accuracy. They were placed 4 metres apart, making it accurate to about 20 centimetres. In future, recording the speed at which objects pass by would make more accurate judgments possible.'"

5 of 106 comments (clear)

  1. Open source surveillance by PhysicsPhil · · Score: 1, Interesting

    Does the fact that this will be an open-source application compensate for the fact that this introduces yet another method of surveillance into society?

    1. Re:Open source surveillance by jibster · · Score: 4, Interesting

      Maybe the glass is half full.

      Think of a peaceful protest group using, an admittedly far superior, form of this to camera swarm the police. The perpetrator of any action, a policeman clubbing an innocent citizen for instance, might question their actions if they knew they were surrounded by this swarm.

  2. F&TF3: Tokyo Drift by OctoberSky · · Score: 3, Interesting

    Is this basically the last drive sequence of F&TF3: Tokyo Drift?

    Where all the kids are viewing/filming the race down the mountain as it goes by?

    I thought that technology (well, that CGI) was rediculous but maybe it's not that far away?

    (NOTE: Give me Karma, I admitted to watching that movie, that's gotta count for something).

  3. concert-recording on the cheap by smellsofbikes · · Score: 5, Interesting

    I've spent some time designing and programming (but will never finish) something similar to this, just using cellphones' audio capabilities. Imagine getting twenty random people at a concert to call into a server and leave their cellphones running, recording the concert from twenty different points. From the overall stream, you should be able to derive an excellent, local-noise-removed bootleg, and from a bit of playing with signal intensities you should be able to figure out where the individual recorders were and do some nice sound balancing.

    We're all carrying these great little computers: we should start doing networked or collaborative stuff with them.

    --
    Nostalgia's not what it used to be.
    1. Re:concert-recording on the cheap by Jherek+Carnelian · · Score: 3, Interesting

      This might be true with a 44- or 48kHz sampling rate, but "phone quality" 8kHz sampling will give you something that sounds worse than a cassette recorder stuck inside a coffee can. Not so fast there. If it is possible to algorithmically combine a handful of low-resolution (i.e. low sample rate) images of the same scene to get a high resolution version, it ought to be possible to algorithmically combine a handful of low-resolution recordings of the same audio to get a high resolution version.