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Computer Scientists Scour Your Holiday Photos

Posted by CmdrTaco on from the fanny-pack-detected dept.

Barence writes "Hundreds of thousands of images on Flickr are being used to teach a program to determine the geographic location of an image, simply by looking at it. The program attempts to mimic the way that humans can deduce the location of an image by searching for visual clues, such as similarities to pictures or locations they have seen previously. In its current state it can guess the location of a photo to within 200km, 16% of the time — extremely accurate given the complexity of the problem."

5 of 156 comments (clear)

  1. Where pictures are taken by tomalpha · · Score: 5, Informative

    The paper referenced in the article has an interesting density map of where their 20 million source photos were taken (ok, so they only ended up using 200 or so of these). It says it uses a logarithmic scale, and seems to imply that the vast majority of photos available to them on Flickr were taken in one of only a handful of locations:

    • London
    • Paris
    • New York
    • Washington
    • Los Angeles
    • Tokyo

    Ok so there are a couple more than this, and my geography is appalling, but these seem to be the only areas that are are coloured red.

    1. Re:Where pictures are taken by Falkkin · · Score: 3, Informative

      If you RTFP, Figure 6 shows the difference between the performance of the algorithm and random guessing. It's pretty significant.

  2. Photosynth looks cooler by Bombula · · Score: 4, Informative
    The Photosynth multi-resolution and image-recognition tech demonstrated at TED looked cooler if you ask me:

    metacafe link here and TED link here.

    --
    A-Bomb
  3. Re:Random pick is correct ~8% of the time by Anonymous Coward · · Score: 4, Informative

    Re-check your math that is wrong.
    Should be .08%

  4. Re:Lies, Damned Lies, And... by SQLGuru · · Score: 3, Informative

    Surface area of a sphere = 4*pi*r^2
    Radius of the Earth = 6 378.1 kilometers (from Google: http://www.google.com/search?hl=en&rlz=1T4ADBS_en__230US231&q=radius+of+earth )

    Surface area of Earth: 510,065,600 km2 (http://www.google.com/search?hl=en&rlz=1T4ADBS_en__230US231&q=surface+area+of+earth)

    Percentage of surface area that is land: 29.2% (http://www.physicalgeography.net/fundamentals/8o.html)
    Surface area of Earth that is land: 148,940,000 km2 (same source)

    Area of a circle = pi*r^2
    Radius of "target" = 200km
    Area of target = 125663.7km2

    Number of "target" areas that could fit on the surface of the Earth covered by land (assuming too few landmarks to identify pictures take over water, so they will be excluded): 1185.2

    Chance of being right by pure dumb luck - 1 in 1185.2

    Layne