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The Hidden Security Risk of Geotags
pickens writes "The NY Times reports that security experts and privacy advocates have begun warning consumers about the potential dangers of geotags, which are embedded in photos and videos taken with GPS-equipped smartphones and digital cameras. By looking at geotags of uploaded photos, 'you can easily find out where people live, what kind of things they have in their house and also when they are going to be away,' says one security expert. 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."
Might want to take a look at jhead. jhead -purejpg will, as the name suggests, strip everything that isn't actually the image.
http://www.sentex.net/~mwandel/jhead is a nice Exif Jpeg camera setting parser and thumbnail remover. Try it and get scared. Geotags are new, but the problem has been there for years. The "hidden" parts of images give away camera model, camera time, camera serial number and that is just the tip of the iceberg. Always open and save images in some editor such as GIMP before uploading them to the Internet(s). This is a good idea anwyay as viewers will generally be more happy if you crop the picture, perhaps adjust the color balance etc.
9/11: Never forget it was a false-flag operation
Yes, I was going to recommend jhead as well. I haven't used it for deleting EXIF headers, but I have used it to get a list of what focal lengths I've used for all of my photos. It's a handy free utility, and I wish it worked on RAW photos as well.
Slashdot's first reaction to VMware
You can use the "-strip" command-line option with ImageMagick's "convert" utility to strip out all the metadata from an image prior to uploading it.
The Lumber Cartel, local 42 (Canadian branch)
British Columbia, Canada
This is why upload services should simply just strip out the un-needed info of the pictures. The original pictures still have the sometimes useful geolocation data, but your Facebook pictures won't.
But is it wise to be trusting your services (i.e. Facebook) to take these extra steps to protect your privacy? Wouldn't it make more sense to have an educated consumer base who can be careful what they upload in the first place? At the very least, the value of this information to marketers would make it unlikely that free, online services like Facebook would simply throw this valuable data away. It would make more sense for consumer electronic devices to do a better job of informing the user of what information is "hidden" in the media files they create, with a default off option for anything "hidden".
If I can be modded down for being a troll, can I be modded up for being an orc, or a balrog?
I always use IrfanView to pre-process my pictures before uploading them anywhere. You need to do that anyway (original pictures are usually huge 4000+ pixels wide and forums usually limit you to less than 1280px). When you're saving the image, it shows check boxes to remove all extra information from the pictures (usually camera model and shooting options and so on). Easy. And yeah, it's an awesome and light image viewer and you can edit images too.
or using imagemagick: mogrify -strip [filename]
Or, you can just use ImageMagick:
$ mogrify -strip image.jpg
Palm trees and 8
Agreed, the OP may have over-stretched what can be concluded from photographs alone. I think what they were getting at was using geo-tagged photographs and other evidence such as tweet posts and facebook status updates, and indeed advertising your GPS position could all be used to conclude you're on holiday, plus you've photographed where your house is and all of the nice stuff that's in it. However, unless you make a habbit of uploading all of this information to an entirely public domain I'm not entirely sure there's a danger of all this information getting into the wrong hands...
For those who have forgotten, Google is trying to do location based analysis without the geotags - you send them a picture of a place, they tell you where it is (well, what it is for right now). No geotagging necessary.
Of course, Picasa is kind enough to mark each geotagged picture with a google map pin in the preview window - so you at least know which pics have the metadata in the tags.
Is it just my observation, or are there way too many stupid people in the world?
I see you've heard of PleaseRobMe.com
If you are looking for a tool to read and edit the exif (geolocation etc) information in files, exiftool http://www.sno.phy.queensu.ca/~phil/exiftool/ works on Windows, Mac and Linux and support many formats.
I don't read your sig. Why are you reading mine?
JHead is another nifty utility that blazingly quickly can remove all exif-tags and thumbnails from a bunch of images.