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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."

11 of 156 comments (clear)

  1. Within 200km, 16% of the time? by 14erCleaner · · Score: 3, Insightful

    I'll guess...New York City, without even looking at the pictures that should get me in that ballpark.

    --
    Have you read my blog lately?
  2. This is very hard by mzs · · Score: 4, Insightful

    Look at this set of pictures:

    http://htmlhelp.com/~liam/Hawaii/Kauai/WaimeaCanyon/

    Would you know simply by looking at the photos without the sign that this was not say the grand canyon? The whole correct to 200 km aspect is troublesome when the state of the art in computer vision cannot yet even answer that this is a picture of a canyon.

  3. Missing double blind by RichMan · · Score: 4, Insightful

    From the looks of the test selecting London all the time would have a
    1/6 chance = 16.67% chance.

    They need better double blind testing and a more diverse set of geographical locations.

    1. Re:Missing double blind by zappepcs · · Score: 3, Insightful

      It's a bit worse than that I think. Trying to identify location of a picture by looking at it in the way that humans do requires that you know the location. As an example of why this implies intimate knowledge to be useful, everyone knows of the big statue of liberty. Not just anyone can guess that your holiday picture with the non-descript base in the background was taken at the base of the statue of liberty. The same goes for > 90% of other places in the world.

      Another example: The forests on planets on the show Stargate One, are they in Missouri, Montanna, Canada? Just looking at them will not necessarily tell you anything unless you are intimately familiar with the actual location.

      A photo in Syntagma Square in Athens may look like it was taken in Central Park in NYC if not enough of the background was included. It will take huge amounts of data and photos to get anywhere close to what a human can do at this job, and even then it is limited to only what it has seen before.

      Other knowledge plays a part too. London bridge is now in Arizona (I think) as it was moved brick by brick and re-assembled. Seeing the bridge does not now mean you know where it is .... it's a trick question. The point is that you need additional information as well. A picture that is a beautiful park setting that has a kangaroo in it? is it in Australia, or a zoo? Additional information is required.

      Hats off to them for working on it. It's a tough problem.

      --
      Support NYCountryLawyer RIAA vs People
  4. Re:Where pictures are taken by hagnat · · Score: 3, Insightful

    exactly, its like a d6 die... if i have to identify one (and only one) picture i'll have a 1d6 chance of getting it right

    but when you have to roll this for 200 cities, also chosen by a 1d6 roll, you have two dies being rolled 200 times, and you want to know how many times both dies have the same value

    --
    "life is a joke, and someone is laughing at me"
  5. Re:Where pictures are taken by Rich0 · · Score: 3, Insightful

    If you picked a random point on the globe, and I picked a random point on the globe, then they would be within 200 miles of each other a few percent of the time. If the only logic used by the software was to determine whether or not any land was visible it could probably increase that probability significantly - the earth doesn't have that much dirt poking out of the oceans. 200 miles is a VERY large area of land.

  6. Actually, he kinda understands.... by raehl · · Score: 4, Insightful

    The dice analogy is right-on.

    The problem is he just doesn't seem to realize that the chances of throwing doubles are 16.66%.

    --
    paintball
  7. Re:Where pictures are taken by Belial6 · · Score: 3, Insightful

    Now add to that, the fact that populations tend to bunch together, and you can massively increase your odds of those two point being within 200 km of each other. This is without any image recognition at all.

    With the most basic of image recognition, you could narrow things even farther with things like, "Is there ocean in the picture?", "what is the height of buildings in the background?", or "how many people are in the background". One almost needs to ask how they got their accuracy so low...

  8. Re:Where pictures are taken by raehl · · Score: 4, Insightful

    Actually, the earth is pretty big - you'd have only a 0.0246% of being within 200km of someone, counting water. Get rid of water and you get to around 0.075%.

    --
    paintball
  9. Re:It helps.. by gstoddart · · Score: 3, Insightful

    Do you think it helps or hurts that my photos on Flickr have titles like "Tokyo - Ueno park"?

    For the researchers, it probably helps. They chose pics that had either GPS or location information -- so they could manually verify where the photos originated.

    If they started out with a bunch of pics they didn't have any location information about ... they'd never be able to measure their results. ;-)

    Cheers
    --
    Lost at C:>. Found at C.
  10. Re:Where pictures are taken by 1729 · · Score: 4, Insightful

    That's if you choose points at random. If you only choose points corresponding to cities with large populations that frequently use internet photo-sharing sites, then your chances of being within 200km of the location become much better.