filterMeta

April 30, 2015 9:26 AM

[EXIF] Metadata: MetaUseful & MetaCreepy

IrfanView, as mentioned in comments.
The Top 12 Myths about Embedded Photo Metadata
Tutorial: Metadata Analysis
If I use the challenge photo from Name That Vista with Online photo EXIF metadata reader I find it was taken at 37"17'59.42 N 122"6'56.24 W with an iPhone 5s

posted by the man of twists and turns (20 comments total)

EXIF has been around for years, and there's still no simple consumer-friendly way to view and edit ALL metadata attached to an image.
posted by blue_beetle at 9:35 AM on April 30, 2015 [2 favorites]

The weird thing about this article is that it defines "metadata" as "Metadata is data that is often included with an image, such as the time it was taken, the type of camera that was used, and yes, if you are lucky — GPS coordinates." That's misleading as metadata is actually "data that describes other data" and images aren't the only thing that have metadata. There's metadata in audio files, in documents, spreadsheets, etc.
posted by I-baLL at 9:43 AM on April 30, 2015 [2 favorites]

This reminds me that I should really make sure none of my gadgets are splattering my GPS coordinates all over the web via photos.

Not that they aren't already splattering my GPS coordinates and god only knows what else all over a few hundred databases owned by sundry corporations and a government or six, just because constantly tracking the shit out of everyone is what mobile devices are actually for.
posted by brennen at 9:56 AM on April 30, 2015

Also, I use EXIF viewer, which is an add-on for Firefox to view the exif data of images online. If you're on a windows pc you can also view some exif data by right clicking on an image file and selecting "properties" and selecting the "details" tab.
posted by I-baLL at 9:58 AM on April 30, 2015 [1 favorite]

For the record, Adobe Bridge has a pretty complete EXIF viewer, and I think it's now free if you install Creative Cloud.
posted by neckro23 at 10:11 AM on April 30, 2015

Mac users can view EXIF data with the Preview app. cmd-I
posted by ardgedee at 10:21 AM on April 30, 2015 [2 favorites]

I guess it's not at the level of Apple-style user friendliness, but Phil Harvey's exiftool is very nice in that it's grabs lots of information from the "maker notes", which is data encoded in a format designed by the camera maker. The maker notes are a part of the EXIF spec, but are treated as a block of un-parsed data.
posted by about_time at 10:29 AM on April 30, 2015 [1 favorite]

I-baLL: "The weird thing about this article is that it defines "metadata" as (...) ""

I think this is fine in the context of the article and its intended audience. If my topic is image analysis and the audience is policy experts, I'd probably want to keep things pretty focused. Maybe a followup article after the fact expanding on metadata.
posted by boo_radley at 10:29 AM on April 30, 2015 [1 favorite]

> … there's still no simple consumer-friendly way to view and edit ALL metadata attached to an image.

That's because the market for such a thing would likely be vanishingly small. All metadata encompasses a huge range of encoding schemes, and even just to read and understand it takes a huge amount of code - witness Phil Harvey's ExifTool, which goes to baroque lengths to be able to edit metadata from many image formats. My Canon compact spits out over 160 metadata fields; few people would be interested in them all.

Then there's the matter of what metadata should be editable. Data such as colour profiles you probably want to have sticking around and not have people mess with - but all that good intention can easily be done by using an old photo editor that doesn't know anything about colour profiles. Location data you might want to be easily removed, but for me, it's often the most valuable thing.

(Why yes, I do take a photo of my GPS's clock screen before a photo outing, and carry it along as it quietly logs locations. Once I get home, I use that photo to correct the camera clock, then geotag every photo using exiftool from the track data. You mean you don't?)

For me, there is a special hell for those who fuck up metadata for no good reason. Apple, I hope you like the heat.
posted by scruss at 10:32 AM on April 30, 2015 [2 favorites]

scruss: "Apple, I hope you like the heat."

oh my god what is that url
posted by boo_radley at 10:36 AM on April 30, 2015 [3 favorites]

Ahem. Let's try that URL again, now the edit window is closed, without the pasto:

Apple, I hope you like the heat.

(note to self: mic drops less effective if you trip over the cable on the way offstage.)
posted by scruss at 10:46 AM on April 30, 2015 [7 favorites]

Is this where I complain — quite vehemently— about the sheer idiocy of the EXIF specification not having anywhere to specify the time zone along with the date/time?
posted by DevilsAdvocate at 10:52 AM on April 30, 2015

Even without using Exif data Google can do some pretty cool/creepy things with your pictures.

I uploaded a bunch of pictures onto my Google Drive and it was able to make a story of a day trip my family had taken from Kyoto to Nagoya. Like it had a map with Kyoto as the starting point and then a map with Nagoya before showing the photos taken there. I guess it was able to do some matching with landmarks or similar photos or something (although the only photos from Kyoto were the bullet entering the station and couldn't that have been anywhere?)

My camera didn't have any GPS data and I was using a Blackberry at the time (and not using any data) so my phone wasn't ratting me out as it does now, but somehow Google was able to piece it all together. I was more impressed than creeped out but other people may feel different.
posted by any portmanteau in a storm at 10:54 AM on April 30, 2015 [2 favorites]

boo_radley: All I'm saying is that it should not give an incorrect definition of "metadata". That's all. Other than that it's a great article.

Also, a while ago I remember looking into a gif file and seeing plain text comments in there. So I just googled for gif metadata and found this link:

http://www.forensicswiki.org/wiki/GIF
posted by I-baLL at 11:20 AM on April 30, 2015 [1 favorite]

If you're intimidated by using command line tools but want to see what ExifTool can do there's a cross-platform GUI wrapper for it called pyExifToolGUI that will let you browse to your photos and display the info without you ever needing to type anything. ExifTool is pretty great, I actually just had a post on ask.metafilter where it was recommended and I'm now using it for a project to rename the photos I take with the date and time they were taken but that's just the tip of the iceberg of what it can do.
posted by metaphorever at 11:44 AM on April 30, 2015

Yup, lots of cool things can be done with (and big mistakes can occur because of) image metadata.

One important thing to remember is that some image-hosting site (Imgur, among others) automatically strip off EXIF metadata when images are uploaded. This can be good or bad, depending on what your goals are in posting (or investigating)...
posted by QuantumMeruit at 11:56 AM on April 30, 2015 [2 favorites]

I was at a talk a couple of years ago by a guy who was an expert on device security. That talk was interesting for a couple of reasons (first time I'd heard of the automated plate readers and cellphone towers used by law enforcement). One of the most memorable elements of the talk was a side project for tracking stolen phones and cameras by renting out machine time and using those computers to trawl through public-facing EXIF data to find stolen equipment.
posted by fifteen schnitzengruben is my limit at 12:27 PM on April 30, 2015 [1 favorite]

"One of the most memorable elements of the talk was a side project for tracking stolen phones and cameras by renting out machine time and using those computers to trawl through public-facing EXIF data to find stolen equipment."

If I remember correctly, Flickr used to be able to let you do that though I'm not sure if they still do.
posted by I-baLL at 12:48 PM on April 30, 2015

And then there's the likely hidden metadata, like colour printers' Printer Dots.
posted by scruss at 2:10 PM on April 30, 2015

find . | while read f; do mat -b "$f"; done
posted by anarch at 2:21 PM on May 1, 2015