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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."

56 of 156 comments (clear)

  1. Like Sex Panther... by dlaudel · · Score: 2, Funny

    16% percent of the time it works every time.

  2. 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 Ethan+Allison · · Score: 2, Informative

      There are way more than 6 sources, check the map.

    4. 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.
    5. 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"
    6. Re:Where pictures are taken by danaris · · Score: 2, Funny

      No, I think you're misunderstanding how this works.

      Given that there are 6 locations where all (or nearly all) of the pictures being used were taken,

      Deriving from this that the probability of getting any 1 of these right by random guessing is 1 in 6,

      Given that the accuracy averaged over 200 pictures is slightly less than 1 in 6,

      The computer does slightly worse than chance.

      However, my guess is that the first given is not entirely correct ;-)

      Dan Aris

      --
      Fun. Free. Online. RPG. BattleMaster.
    7. 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.

    8. Re:Where pictures are taken by Melfina · · Score: 4, Funny

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

      --
      :3 rawr.
    9. 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...

    10. 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%.

    11. 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.

    12. Re:Where pictures are taken by Naughty+Bob · · Score: 2, Funny

      then... if there are 6 sources of pictures, by blindfold guessing you'll get it right 16.66..% of the time If they're smart, they'll only ever guess one of two points:

      point a) Halfway between NY and Washington DC
      point b) Halfway between London and Paris

      This should give them a better than one-in-three chance of being correct to within 200km, as long as their program can take a decent stab at guessing which of the two sets is the more likely....
      --
      "Be light, stinging, insolent and melancholy"
    13. 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.

  3. 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
  4. 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?
    1. Re:Within 200km, 16% of the time? by Bearpaw · · Score: 2, Funny

      Wait, don't tell me, let me guess where you're from ...

  5. 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.
  6. 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
  7. 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).

  8. 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?
  9. 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.
    1. Re:Statistics is important by stainlesssteelpat · · Score: 2, 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
      But it couldn't sample the population here, on account of the tinfoil hats.
      --
      War is the statesman's game, the priest's delight, the lawyer's jest, the hired assassin's trade.- Shelley
    2. Re:Statistics is important by raehl · · Score: 2, Funny

      That was much funnier before I started working out of my basement.

  10. 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
  11. 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.

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

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

    1. Re:Source code by Anonymous Coward · · Score: 2, Funny

      And if I had mod points you'd lose 1 for being redundant/pointless. This isn't digg where what you think matters unless you have those mod points.

      The irony...oh god, the FUCKING IRONY!

  13. 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.
    2. Re:This is very hard by Facegarden · · Score: 2, Interesting

      I would know it was Waimea Canyon because I've been there, and to the Grand Canyon, and as others have said the amount of vegitation and steepness of the walls differentiate the two very clearly, and i know that canyons that large are rare (on earth, above water), so it is unlikely to be some other place i just haven't been. :)
      But i know a lot more than computers.

      This all brings up an interesting point though... When you're in an unfamiliar place, but your friend knows the area, they can always tell you where you are, more or less. When machines get good enough to have a complete knowledge of the entire earth down to a sufficient resolution, they WILL be able to look around, anywhere, and tell you where you are, without GPS.

      Also, they will be able to direct you to the nearest human enslavement camp.
      -Taylor

      --
      Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
    3. Re:This is very hard by SpinyNorman · · Score: 2, Insightful

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

      Yes, because the GC doesn't have so much vegetation growing down the sides.

      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.

      The two things arn't related. You don't need to know it's a canyon to be able to locate it - you just find the closest match in your database and give that as the location. You only need to be able to assess degree of similarity. No need to start reading signs or logically analysing the picture for clues.

      Getting the location right to 200 km doesn't really say anything about the accuracy of your matching algotithm - it just says that:

      a) You have a database with at least one picture per 200Km radius

      b) Enough locations (at least in your database) look sufficiently distinct that "distant but similar" matches occur infrequently enough not to drag your success rate below 16%

  14. 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.

  15. Lies, Damned Lies, And... by jesdynf · · Score: 2, Interesting

    200km, 16% of the time? I guess that sounds sorta neat... except that 84% of the time, it's off by more than 200km. Now, we know that the earth's circumference is 40000km, and it follows that nobody can ever be more than 20000km from any location on Earth.

    So 16% of the time, it's accurate to within one percent of the TOTAL RANGE OF ERROR. The other 84% of the time, you're on your own. I wonder if I could manage that kind of accuracy just by sampling colors, classifying them by terrain, and then just picking a likely spot at random.

    --
    Yahoo! Pipes are awesome. How awesome? http://pipes.yahoo.com/jesdynf/slashdot
    1. 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

    2. Re:Lies, Damned Lies, And... by raddan · · Score: 2, Insightful

      Your post made me think of something-- the Earth is really BIG! But I'm a nerd, so I had to prove it to myself.

      The surface area of the Earth, not counting water, is 510,072,000 km^2, according to Wikipedia. So, that's roughly 5.1 x 10^14 m^2. Again, according to Wikipedia, there are currently 6.67 x 10^9 people on Earth. That translates to about 7.65 x 10^4 m^2 for each person! In terms that Americans can understand, that's roughly 14 football fields (or to choose a landmark close to me, a little bit larger than Fenway Park). When you consider the fact that metro areas often have millions of residents, you realize that we're pretty lumped together, distribution-wise.

  16. 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 klenwell · · Score: 2, Interesting

      From the looks of the test selecting London all the time would have a
      1/6 chance = 16.67% chance. Indeed, not very impressive for London.

      Look at this guy's claim for basic audio analysis:

      "Simply phonetics. The science of speech. That's my profession; also my hobby. Happy is the man who can make a living by his hobby! You can spot an Irishman or a Yorkshireman by his brogue. I can place any man within six miles. I can place him within two miles in London. Sometimes within two streets."

      And that was almost a century ago!
      --
      Innovation makes enemies of all those who prospered under the old regime... -- Machiavelli
    3. Re:Missing double blind by darkstar949 · · Score: 2, Interesting

      Wikipedia to the rescue - http://en.wikipedia.org/wiki/London_Bridge - London Bridge is actually pretty interesting as well as the original one was demolished, the second one was moved to Arizona, and the third one currently standing in London was built between 1967 and 1972.

    4. Re:Missing double blind by Woundweavr · · Score: 2, Insightful

      Accents used to be much more pronounced pre-radio/mass media. I know in Boston, individual streets had slight variations so that you could tell the neighborhood of a person by their accent. However, now that a large percentage of the words we hear are from movies/TV/radio our accents get washed out.

    5. 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.
  17. Yes, I'm an idiot. by SlashTon · · Score: 2, Funny

    Yes, I meant through the Earth distance and yes I did manage to use the radius.

    That will teach me to post before drinking my coffee...

  18. 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.

  19. 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%

  20. Problem with flickr geo-tagging by stoofa · · Score: 2, Insightful

    The problem with geo-tagged flickr photos is that in many places the detail on the maps and aerial shots provided isn't defined enough to allow an accurate placement.

    The even bigger issue is that, although some cameras now have GPS, the majority of geo-tagged shots are placed manually by humans who often get it wrong or deliberately place their photos onto a more popular location just to increase their traffic.

  21. 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)

  22. 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%.

  23. 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!

  24. Actually, it's not as hard as you might think by Khopesh · · Score: 2, Interesting

    There's an upcoming paper coming from MIT on this topic, Recognition of Natural Scenes from Global Properties: Seeing the Forest Without Representing the Trees that proves this isn't as hard as you might think.

    To sum up this massive paper in a very small (and likely highly imprecise) nutshell, building models up from basic objects (the traditional method) is only one way to approach this. Using this method, you are correct; it's impossible to understand what a canyon is. Using the new global properties methods in this upcoming paper, you can gather basic elements that could easily help in assigning location properties, understanding that something pictured is a desert or forest, and theoretically using that data to help determine which desert or forest (this latter portion is beyond the scope of the paper, but great fodder for a future paper that builds upon these fundamentals).

    While the method currently requires a high level of labeling in its images, it is hoped that this labeling becomes unnecessary on larger data sets.

    --
    Use my userscript to add story images to Slashdot. There's no going back.
  25. 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.
  26. 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