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Computer Scientists Scour Your Holiday Photos

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."

38 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 elguillelmo · · Score: 5, Interesting

      then... if there are 6 sources of pictures, by blindfold guessing you'll get it right 16.66..% of the time

      --
      Dawkins Revisited: A person is shit's way of making more shit -- Steve Barnett, anthropologist.
    2. Re:Where pictures are taken by SteveAyre · · Score: 4, Funny

      So it's actually less accurate than if it just guessed? :)

    3. Re:Where pictures are taken by elguillelmo · · Score: 3, Interesting

      I'm not with you in the argument. Assuming there are just 6 cities, and that the proportion from each is the same: 1/6, if you guess randomly you are right 1/6 of the time. It's just like a die... Then, if there are zillions of sources but only six cities amount for most of the pictures, then randomly guessing among them will get you close to this 1/6...

      --
      Dawkins Revisited: A person is shit's way of making more shit -- Steve Barnett, anthropologist.
    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. Re:Where pictures are taken by Melfina · · Score: 4, Funny

      It's like answering 'True' in a multiple choice test!

      --
      :3 rawr.
    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%.

    9. 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.

    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.

  2. Dude where's my photo by stainlesssteelpat · · Score: 5, Funny

    Dude, that's as accurate as my girlfriends map navigation. *sigh*

    --
    War is the statesman's game, the priest's delight, the lawyer's jest, the hired assassin's trade.- Shelley
  3. 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?
  4. What I need by Intron · · Score: 3, Interesting

    ... is a program that will remember the names of the people in the photos.

    --
    Intron: the portion of DNA which expresses nothing useful.
  5. heh by Kingrames · · Score: 4, Funny

    Show it a picture of the andromeda galaxy and throw its statistics way off.

    --
    If you can read this, I forgot to post anonymously.
    1. Re:heh by somersault · · Score: 4, Funny

      Nopes - it will guess "Starbucks", and there's always one within 200km, even in Andromeda.

      --
      which is totally what she said
  6. Obligatory - I can get it within 6378km 100% by SlashTon · · Score: 5, Funny

    of the time...

    (Not counting those rich bastards who can afford taking a holiday on the ISS).

  7. Automatic Carmen San diego by goombah99 · · Score: 4, Funny

    Where's Goatse?

    --
    Some drink at the fountain of knowledge. Others just gargle.
    1. Re:Automatic Carmen San diego by Anonymous Coward · · Score: 5, Funny

      Where's Goatse? Uranus?
  8. Statistics is important by UnknowingFool · · Score: 4, Funny
    Just like all statistics getting a good sample population is very important. If this program were to sample the /. population, it would come to one of two conclusions.
    1. We have no holidays as we don't socialize.
    2. We all live within 1.0 km of a basement. :P
    --
    Well, there's spam egg sausage and spam, that's not got much spam in it.
  9. 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
  10. Scientist make new discovery by Anonymous Coward · · Score: 4, Funny
    Machine is shown hundreds of thousands of holiday pictures from Flickr.



    Scientists surprised to discover it is possible for a machine to loose will to live.

  11. Source code by RandoX · · Score: 4, Funny

    It's a for loop that spits out "Your mom's basement".

  12. 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.

    1. Re:This is very hard by cheebie · · Score: 3, Funny

      Would you know simply by looking at the photos without the sign that this was not say the grand canyon?


      Yes, because there aren't 746 helicopters flying over it.
  13. Just checked on flickr... by stoofa · · Score: 4, Funny

    OsamaBinLaden2001 has deleted his account

    1. Re:Just checked on flickr... by aadvancedGIR · · Score: 3, Funny

      I don't think he has to worry, that program does not seem to be any better that GWB when it comes to determine the right country to attack.

  14. 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.

    2. Re:Missing double blind by Bat+Country · · Score: 3, Interesting

      I'd imagine great work could be done by examining light intensity and coloration (atmospheric red shift) vs date stamp on the image (working from RAW with some camera data), they could guess the latitude fairly accurately. By similar methods you could figure out pollution levels, thus narrowing the sample range further.

      Additionally comparing geometry could help factor out region with plant recognition fairly well also. You're not going to see a saguaro in Kentucky unless you're in a botanical garden. They've got a rather distinctive shape, and somewhat unique coloration.

      Then you've got horizon lines - they're going to be ragged everywhere.

      City skylines can be fairly easily identified the same way barcodes can be recognized, and mountain ridgelines are equally useful. The real trick would be telling a place in western Montana in mid-spring vs a place in western Kansas in early fall.

      --
      The land shall stone them with the bread of his son.
  15. Blue screen your pictures by BMonger · · Score: 3, Interesting

    I propose we all take pictures with blue screen in them (not the whole background, just "enough") and then write a script to randomly replace the blue screen with alternative locations every time the picture loads.

  16. 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%

  17. Moon Landing pictures! by erroneus · · Score: 4, Funny

    I'd like to present this with Moon landing pictures to see where the moon landing was staged! (hahaha... love it)

  18. 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%.

  19. Automatic image recognition is no walk in the park by hedu · · Score: 4, Interesting

    Reminds me of the experiment done in a Dutch military lab a couple of years ago. They trained a neural network to recognize whether a photograph taken out on a country road had a military vehicle in it or not.

    The system recognized the photos from the training set perfectly, but did no better than random on images fed to it that were taken at different times.

    Turns out all the training shots with a military vehicle in it had been taken on a sunny day, and the control shots without one had been taken when it was overcast. The system had been trained to recognize a different thing from what they intended!

  20. 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

  21. 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.
  22. Google by sckeener · · Score: 3, Interesting

    Google should get behind this. I think their Picasa would benefit from it.

    Generate some autotags.

    What would be nice also is if they had a feature where if you labeled someone in a picture, if you uploaded another picture with that person in the picture, the program would prompt to auto tag.

    I've been going through old family photos and it would save so much time if the programs I am using autolabeled based off details in the picture.

    --
    "Only one thing, is impossible for god: to find any sense in any copyright law on the planet." Mark Twain