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Stolen Camera Finder

stolencamerafinder.com

234 pointsobtino70 comments

I had my Canon DSLR body cleaned at the service centre here in Brampton, ON. When I got it back I noticed it felt different--the shutter sound is more thumpy, and etc. I checked the serial number to check if it was really mine and it was. It's all fine but then months later just by some coincidence I saw a photo on Flickr with my e-mail address in the metatags. Some of my photo buddies warned me that Canon is notorious for swapping parts when your cameras are in for service.

Would it be possible to process the images somehow and find the noise profile for every image and match it with existing images?

When I found a directory full of images and couldn't remember which camera took them, I noticed that there were a few fuzzy pixels of green and red if I zoomed all the way in that were present in all photos taken by that camera. I took a photo of a white wall in a dark room (to force high ISO) with a couple of my cameras and found the one. Of course I found out about the EXIF serial number and other unique data later on, but it could still be useful on sites that store the original image but strip EXIF.

Nice idea. This seems possible, unless the image has been cropped/rotated. (It's still possible, of course, but the analysis gets more complicated.)

If this were possible wouldn't cameras already be taking advantage of this to eliminate the noise in the first place?

They do. My Canon PowerShot G3 did this and I've had that since 2004. The way it works is this: the camera takes two photos of equal shutter speed length, except the second is done with the aperture completely closed. This gives you a noise profile on what should be a completely black screen equal to the noise generated during the real photo. The camera then automatically removes the noise from the first photo using the second. Of course, this means you have to wait for the camera to take and process the second shot, which could be up to several seconds long. This is naturally only done on low-light shots though, meaning things like dead pixels are still present on most photos.

The "green pixel" in your camera is a hot pixel, probably due to a partially defective sensor. This isn't guaranteed to occur in all (or even a significant number of) cameras.

Not to mention noise is, by definition, high entropy and hard to predict. There are patterns to noise due to sensor design and manufacturing, but that would make it unique to the sensor design, not to a specific copy of it.

Yes, it is possible and it has been done. Here is a paper that talks about it: http://isis.poly.edu/~forensics/pubs/investigation08.pdf

I did a summary presentation of the topic and paper. PPT: http://dl.dropbox.com/u/716143/digicam-fingerprint.ppt PPTX: http://dl.dropbox.com/u/716143/digicam-fingerprint.pptx

EDIT: The paper I linked above details source identification by recognizing patterns in demosaicing artifacts. In that paper the authors combined the demosaicing fingerprinting with their earlier noise fingerprinting work: http://isis.poly.edu/~forensics/pubs/icme2007.pdf

So if I find a photo I like, I can find all other photos taken by the same camera? Is there potential for stalking here?

I guess Amateur porn just got a lot less anonymous.

Holy christ you're right. There are whole communities online of amateurs that publish their own 'adult' photos. What's the likelihood that they also post their family/other photos elsewhere online?

Pivot.

I assume most places like that would strip exif data already.

Imgur does, for instance.

In my opinion, personal blogs are a bigger problem. Even wordpress.com does not sanitize pictures. I believe many bloggers are unaware of that.

They should watch out anyway. This isn't anything that 4chan could theoretically do (although it now has become a lot easier)

4chan retains exif data afaik

Thats what they want you to think

People should strip it themselves (no pun intended)

It could be an easy way to find work by a photographer you like. ie, if you see a cool landscape, just drop it in and find the photog and their works.

Also an easy way to frame someone with a quick exif edit.

I think it could help to add a feature "I've found camera/sd card/other device with photos". Just an anecdotal evidence, but my friend's friend found an iPod with some photos few years ago and couldn't locate the owner. Surely it doesn't happen very often, but if this site gained enough popularity, it could be really helpful.

It's a good idea, I found a Sony Memory Stick (back when they were quite expensive), I would have liked to track the owner as well.

Good idea, but works most effectively when:

(1) Various encode/decode steps along to publishing the photo online don't corrupt EXIF data

(2) Thief isn't sophisticated to wipe/disable EXIF data. Many cameras shoot in a proprietary, higher-bit format and give you a fairly obvious wizard option on a desktop tool to include/exclude the EXIF data.

(3) Thief will use the camera, not sell it immediately into a second-hand market.

(4) Even if your camera is supported, it has to be configured to record EXIF data by both you and the thief. Some proprietary formats are fairly raw and don't always include EXIF-derivable data by default.

This will get some adoption because what other option do users have, but it will be interesting to see how many uploads convert to a lost camera being recovered/thief being apprehended. If users had the ability to leave a testimonial when there is some kind of closure, you could derive a metric of success.

Yup--my camera (Canon 60D) was listed, but when I used a photo that had been exported with Lightroom, it couldn't read the serial number. Only when I gave an original JPEG did it have any success, and it didn't end up finding any photos, since anything I've uploaded has been exported through Lightroom.

I noticed the same a few days ago when I tested it. All my JPGs are exports from Lightzone and there's no serial, my originals are all RAW, so - no luck for those who don't shoot jpeg/raw+jpeg.

I tried it with an old Canon Rebel XTi photo that had gone through Lightroom and flickr. "exiftool" shows a serial number in the image, but the web site does not.

I downloaded the "original" size from flickr - resized flickr images seem to drop most of the exif info, and the "exif info" displayed on the web site no longer shows serial numbers.

Lightroom has an export option called "Minimize metadata" that strips a lot of EXIF out.

You might have "minimize embedded metadata" checked in the export options; uncheck it and I bet the serial will survive the export. Also, if you want more control over exported metadata, Jeffrey Friedl made a plugin[1] for that. I haven't used this particular plugin; I do however use his flickr and geocode plugins, and they're both great.

1) http://regex.info/blog/lightroom-goodies/metadata-wrangler

1) Libraries used to manipulate images tend not to break EXIF data, and many site do not use any encoding at all.

2) Seriously, do you think that a common thief cares about EXIF, let alone know?

3) I have not seen a camera which does not write EXIF -- more probable problem is that it does not write camera serial number.

4) What is the difference? You have similarly small chance of retrieving it, no matter whose possession it is in at the moment.

Most camera's maybe. I'd be interested to see what phones write EXIF, as I would guess phone theft/loss is a more common occurrence. I tried it with my Nexus One but unfortunately it seems that it doesn't log serial numbers in the EXIF data.

Most modern phones do, although as I already pointed out, the real problem phones/cameras not writing serial numbers, not EXIF data as a whole.

Almost every modern smartphone writes EXIF - including Android and iOS.

In fact, EXIF is so common, and so poorly understood by thieves, that your only main fear is image hosts stripping EXIF, or the firmware failing to include serial in EXIF (which is less likely the more expensive the camera).

3) was partly true for me. No serial number is written.

You have no idea what you're talking about.

- 99.9% people shoot JPEG (which has EXIF enabled by default in pretty much every camera).

- Most DSLR owners don't shoot RAW and don't know what EXIF is.

- Most RAW formats contain EXIF information (at least for major brands).

- Most graphic editors do not destroy EXIF data.

- Even if a thief sells the camera, buying stolen stuff is illegal, so you can get your camera back (it's buyer's problem)

I interpreted this

(1) Various encode/decode steps along to publishing the photo online don't corrupt EXIF data

As referring to online photo-sharing sites which will strip out EXIF data for privacy reasons, like Flickr/Facebook/Imgur.

Tried it with a photo taken from a camera I had stolen in Peru:

The 'SAMSUNG TECHWIN CO., LTD. Samsung SL201' does not write serial information in the exif. See the supported cameras page for a list of models that do.

  > a camera I had stolen in Peru

Not the slightest bit of guilt? or maybe you meant

  a camera stolen from me in Peru

The construction you are making fun of means "someone stole my camera" just as much as it means "i stole a camera". From context, though, it's clear that the first is what the author means. No rephrasing is necessary to convey the message; the sentence is 100% correct as-is.

It's obviously pretty unclear in the worst possible way, though, and pretty awkward, too. I disagree that the context makes it completely clear. There are any number of ways to write that sentence without the ambiguity.

You're extending the OP's context to his reply, which is not a given (IMHO, specially at first-level replies, which could be approaching the posted link from any angle).

From the little context provided by his reply, and his reply only, he could could just as well be a literate camera thief hanging out here on HN and using stolencamerafinder.com to upgrade himself from just a thief to a thief + stalker! And the sentence would still be correct as-is! :)

I take it as "you wanted to nitpick to my nitpicking". Fine, heh, I'm just as guilty of nitpicking, but I see it like this: from the ridiculously easy to come by counter-example above, your nitpicking is not standing on solid ground.

Happy nitpicking! ;)

Another neat idea: Allow the user to select their city, the make and model of the camera, and the date it was stolen. Then you can scrape Craigslist from the surrounding area and show possible matches.

What's the database of photos it can search against like? I just tried looking up a photo, the site found the serial number in it but couldn't find any matching photos online. I know the exist, even the exact same photo I was testing with is available on various websites.

That same photo may have had its EXIF data stripped out.

Would have been a direct upload via FTP, no modifications.

Either way, presumably they haven't indexed every photo on the net?

Obviously I'm an edge case, but I'm not using a graphical file manager, so I can't use the drag and drop method of providing a file.

Have you considered allowing users to specify a file by URL, or the browser's browse mechanism for file input?

It's a shame some smartphone cameras (eg, my old Nexus One) don't tag with full EXIF data, else you'd then have a much larger potential userbase.

Interesting reaction. When Intel was going to include a unique serial number in every CPU, I recall a lot of people getting into an uproar over the privacy implications.

For one camera I got: "fail The 'NIKON CORPORATION NIKON D200' does not write serial information in the exif. See the supported cameras page for a list of models that do."

For my other camera, a Pentax K20D which is on the supported list I got:

"Problem extracting serial number. If possible, use an original image from the camera that has not been edited in any software."

The only thing I had done was uploaded the image from the camera via iPhoto. But all the EXIF data was in tact, including the Pentax K20D, the serial #, even the lens I used. So I don't think iPhoto stripped any data.

I'm wondering why if Flickr for example can extract all of the EXIF data, even for images not directly from the flash card, why did this happen?

I doubt this will every successfully result in a stolen camera being recovered. But, it is a cool new idea that certainly has other obvious applications such as finding other photos by the same camera.

Would it be better rebranded to a different purpose?

So this uses exif data, which as people here have noted can be stripped, but can't you still ID digital cameras from things like sensor noise? I haven't looked at the statistical properties of it, it probably changes over time, only works on at high ISOs, and search would be way more intensive, but I know that my camera has a very predictable noise pattern.

The photo itself is not uploaded to the site for checking. Only a few bytes with the serial and camera model/manufacturer are sent in a HTTP GET to stolencamerafinder.com. This makes it very light in traffic.

The site can expand the camera->owner database by searching photos with valid EXIFs on famous sites and correlating it to the user.

No love for RW2 I guess =( Also, add an upload button, I don't want to drag&drop if my browser is full screen!

Not as drag-and-drop easy, but GadgetTrak is working on something similar: http://gadgettrak.com/labs/camera/

Great idea. But instead of a serial input, it should ask for a photo or Flickr account or so. I don't know my cam's serial, and I can't look it up easily if it's stolen.

They do ask for a photo.

They didn't this morning, from my iPad. It can be they do device/browser detection, but they don't tell you that. Now, from my browser they indeed ask for a picture.

This really needs the addition of an "enter a URL" or "upload a photo" interface - drag and drop often does not work! Or does not easily work, anyway.

I haven't gotten this to work once. Cool idea though.

A lot of cameras don't include the Serial Number in the EXIF header. What happens then?

On Chrome, drag-n-dropping from other windows doesn't seem to work (on Windows 7).

This doesn't help very much, but it worked for me (drag from file explorer in W2K8R2 into Chrome 11.0.696.60). Do you have UAC turned on?

Apparently this doesn't work in Firefox. Too bad.

Why the downvotes? it didn't work for me with FF4/Linux nor FF4/Mac. It worked on Chrome, though.

Seems like a neat idea for a search engine, but I tried with photos from 6 different cameras and none of them stored the serial number in exif. I wonder how many models this is actually useful for.

There seems to be a fair number of models that are supported:

http://www.stolencamerafinder.com/listmodels

Thanks, I completely missed that list. I'm going to try and find a friend with one of those so I can play around with this a bit.

That list should probably be linked to from the front page, instead of hidden 4 pages deep.

Interesting that the Canon DSLR do support it, but none of the standard P&S.

I tried a photo taken with a Fujifilm Z37 which is on the supported list. However, the photo didn't display a serial number on the EXIF data. I'm pretty sure I've never seen an option in a camera to not write just the serial number. Perhaps the list isn't 100% correct?

The project is a great proof of concept, the chances this will get someone's stolen camera back is pretty slim. We have a similar project, but it searches for the data using existing search engine data. Only about 25% of cameras will embed the serial number, then when uploaded only a few sites will retain the EXIF data, or provide it through meta data. A few that keep the EXIF data or provide it in meta data include:

Flickr.com DeviantArt.com SmugMug.com Picasa.com

Some of these sites strip out some tags. Some manufacturers have custom EXIF tags like Nikon which may store the serial in a "Serial Number" tag or a tag called "0x00D".

Terrible idea. EXIF data is not reliable. You can make it say anything you want.

Do most thieves tinker with or strip the EXIF data then? Otherwise it seems like a good utility for the common case.

I don't think this fact makes it a terrible idea, perhaps just a less-than-perfect method for finding the stolen camera.

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