This is neat:Geofences are special locations that deserve their own geo privacy settings. Simply draw a circle on a map, choose a geo privacy setting for that area, and you're done. Existing photos in that location are updated with your new setting, and any time you geotag a photo in that area, it gets that setting too.
Problem: if you uploaded the picture to Flickr with the GPS info in it (like from a phone, or if you geotagged), that location information is still available from the image you can download, "geofence" or not. It was already the case if you didn't elect to show the location. Flickr does not strip it.
It is as easy as using FxIF (Firefox add-on) on the image when view the original that Flickr offers.
I assumed that they would strip it, but that's a pretty blatantly obvious oversight.
You've misinterpreted what this does. The logic is: If I upload a photo, and it has geocoding that says it's in the radius of my house, mark it as visible to [Friends/Family/Friends&Family/Private].
There's no logic that strips geotags involved, as far as I'm aware.
Oh no, nevermind. It appears I misread it. Ignore me.
Like, so obvious that I didn't mention it because it was literally the first thing I thought of. Geez.
And I missed the little note on Flickr page where they actually say that. *doh*.
(can't delete your own comments on WP it seems)
Doesn't the geofence prevent you from seeing the photo anyway? So you can't download it, regardless of whether it contains location data or not.
Or did I miss the point?
I thought the point was, I want to show this photo to everybody, but I only want to show its location to some people. At least, that's a totally reasonable use case.
Also if someone links you directly to the _o.jpg of a Flickr photo, I think you can download it anyway, can't you?
The link would only work for the members allowed to see the photo at all who are also allowed access to original versions of your photos - those groups can be defined separately.
If you try to navigate to the Flickr page itself containing the image then only those people who are allowed to view the pic can do so. The necessary privacy settings are obeyed. *However* Jamie is right, if you know the direct link to the jpg (the farm7.static.flickr.com.blah.blah.jpg one), you can download to your heart's content regardless of what group you're in.
Of course, the question is, if you were not allowed to visit the Flickr page to begin with, how could you obtain the direct link URL? To which Jamie already answered: because someone who was allowed to view the page sent you the URL.
...which happens all the time when someone hotlinks a Flickr image onto their blog elsewhere.
Update: according to the Flickr forum thread about this very topic, Geofences apparently have nothing whatsoever to do with who can see or download an image. This *only* pertains to who can see the location of your photo on their little map viewing thingy.
So Geofences are somewhat less cool than I initially thought they were.
Now, I didn't read the article, but from the summary it sounds like that if you define the fences shown in the picture, only contacts can even see your school photos at all, not just their location.
I think this is a way of forcing Flickr to impose a sensible default without remembering to fiddle with the settings every time you upload something, a way of saying "look: whenever I upload anything taken from inside these confines, it's meant only for these people". That seems to make more sense than just hiding the location since you could figure out the location by other means.
I see one vulnerability: If you take enough photos, people might infer your private locations by the absence of photos in a certain radius.
That assumes that your photo locations are spread more or less randomly throughout.
If I don't have any photos taken in the Bronx (famous gay bar area/a catholic church/opposing political party headquarters), does that mean I never go to the Bronx (etc), or that I go but hide it well?
"If you take enough photos"
The circular radius might be noticeable on someone's photo map if they've got enough photos in the area near their hidden location (maybe they take random photos on their iPhone of funny dogs they see on the street while going for a jog).
If you can see the outline of the circle you can find the center, revealing the person's hidden location.
It doesn't have to be random, it just has to cover a section of one of the circles.
[...] technology at the heart of this trend is called geolocation; and with a GPS-enabled smartphone such as the Apple iPhone, Google Nexus One, or RIM BlackBerry, [...]
[ I was part of a team working on this ]
If the original photo uploaded to Flickr includes geolocation info in the EXIF, it will be available if the user allows access to their original image file (ie., the JPEG binary exactly as it was uploaded.) Regardless of this setting, EXIF is not included in the smaller "screen size" and thumbnail-size images we generate and use on the site.
But you critters have "View EXIF Info" under the "Actions" for ... everything?
I find that vaguely creepy because the camera S/N is in there if the manufacturer decided it should be. Which makes me easily identifiable by being the only person on earth to have rigged up a rube-goldberg contraption to strip the MakerNotes before uploading.
[Of course that's useful for people trying to find stolen cameras, so tradeoffs.]
Access to the EXIF "page" for a photo is also controlled by an account preference. We also don't show certain fields on this page to non-owners - for example, geo lat/long coordinates. I think it's good to encourage sharing by giving users control and options, so they can share to the degree they're comfortable with.
Point taken. I guess my personal *tinyfistshake* is that I'm beyond happy to share exposure details if it helps anyone (and used same to select hardware in the first place) but can't avoid feeling creepy about the "risk" of having unique_hardware_identifier on file even though I'm never going to take a picture of anything Interesting anyway.
It seems like it'd be useful for flickr uploader tools to have preferences to strip certain classes of EXIF info by default.
Of course, even with that, your camera is identifiable from its sensor noise pattern (more!).
[...] technology during a heart of this trend is called geolocation; and with a GPS-enabled smartphone such as a Apple iPhone, Google Nexus One, or RIM BlackBerry, we [...]