Geotracking

[Tuesday Afternoon]

Is it true that you can find the location of a photograph that has been posted on the internet?

[woo me with science]

1. Try this:

http://www.tineye.com/

[woo me with science]

2. Oops, sorry.

I think I misunderstood what you were trying to do.

[Tuesday Afternoon]

3. I heard something on the radio yesterday to the effect that one

can trace the location of where a photograph was taken by using the geotracker app.

something like this perhaps...

http://www.amazon.com/gp/blog/post/PLNK9GXCR7CGQD83

[Gormy Cuss]

4. I think that refers to photos taken on GPS-enabled devices like cell phones

and I swear that someone on DU posted about this earlier in the week.

[petronius]

5. As I understand it, some new cameras have built-in GPS, which can record

the location of the photo. This info can be stored in the image file itself, along with all the other data the camera records (time, shutter, aperture, etc). If you don't know your camera is doing this, it's possible to unwittingly reveal the location of the photo by distributing the image.

For cameras without onboard GPS this can't happen, unless you've attached an aftermarket GPS to the camera - in which case you'd certainly know about it...

[Tuesday Afternoon]

7. the way I understood it, if you have this capability you can

geotrack any photo on the net. Say I posted a picture of my backyard, you would be able to tell where is my backyard.

[blaze]

8. It might...

If the camera you took the picture with was enabled to include this info in the embedded info (exif), then yes, it's possible.

The photo hosting site I use, allows you to prevent people from looking at the exif.

[petronius]

9. I really don't see any way that could happen without a GPS-enabled camera or phone

Of course, if some really really wanted to track down a picture, they could probably find a lot of clues to the area by studying things in the picture (like sun angles, weather, plants and animals, rock types, etc) but that would be a huge amount of work for an iffy result.

I'm pretty sure I remember the article you're thinking of - a guy posting a picture of his car in the driveway, or something - and it was a case of someone using a camera with the built-in GPS turned on...

[kentauros]

10. The process for tracking where an image would go that isn't georeferenced

would require the use of high-resolution aerial images. What's available online for free is usually of a resolution no better than a few meters per pixel. The high-res stuff we use in mapping usually doesn't get any worse than one-meter per pixel and often goes down to the 6" per pixel resolution. At that level you can differentiate between the human and the dog going for walkies ;)

They're also very expensive to acquire and usually in large format tiff files. Unless you use some kind of GIS or CAD software for mapping, you also won't be able to get the image into the proper georeference. GPS or surveying points makes that possible :)

[petronius]

11. But you're talking about referencing aerial or satellite images, or scanned maps,

or something like that, right?

I get the sense that the OP is asking about locating any random image that lacks embedded coordinates. For example, if I go outside and snap a picture of my rose bush using an old camera and post it online. I can't think of any automated process that would do that...

[Tuesday Afternoon]

12. I think you are right ... I found this article

http://www.nytimes.com/2010/08/12/technology/personaltech/12basics.html?_r=2&emc=eta1

When Adam Savage, host of the popular science program “MythBusters,” posted a picture on Twitter of his automobile parked in front of his house, he let his fans know much more than that he drove a Toyota Land Cruiser.

Embedded in the image was a geotag, a bit of data providing the longitude and latitude of where the photo was taken. Hence, he revealed exactly where he lived. And since the accompanying text was “Now it’s off to work,” potential thieves knew he would not be at home.

Security experts and privacy advocates have recently begun warning about the potential dangers of geotags, which are embedded in photos and videos taken with GPS-equipped smartphones and digital cameras. Because the location data is not visible to the casual viewer, the concern is that many people may not realize it is there; and they could be compromising their privacy, if not their safety, when they post geotagged media online.

Mr. Savage said he knew about geotags. (He should, as host of a show popular with technology followers.) But he said he had neglected to disable the function on his iPhone before taking the picture and uploading it to Twitter.

[kentauros]

13. Yes, I am.

Consider, too, how much some of us reveal about where we live (through things like user profiles) then a determined individual could conceivably figure out where that rose bush is, with enough access to high-res images ;)

It would be like doing a very large jigsaw puzzle, but it could still be done. The geotag makes it simple enough that a child can do it. It still has its positive uses, as I indicated at the bottom of the thread :)

[kentauros]

6. In some cases, this would be a good thing,

like if you're uploading your holiday shots to Google Earth. That way, you can get them positioned in the right place on the globe.

In the world of modern mapping, it's absolutely necessary that photos (aerials) be "geo-referenced" or it wouldn't be as easy to make the maps everyone takes for granted ;)

[Bossy Monkey]

14. Here you go: