Arm Horns (The Hair Web)

This is Eric. We loves him!

Internally, the nomenclature for tags goes something like this: There are “raw” tags (the actual tag you enter on a photo), “clean” tags (the tag that you see in a URL), “machine tags” (things like upcoming:event=2413636) and machine tag “extras”.

Machine tag “extras” are what we call the entire process of using a machine tag as a kind of foreign key to access data stored on another website. Small pieces (of data) loosely joined (by the Internets).

For example if you tagged a photo with upcoming:event=2413636 that would cause a robot squirrel on the Flickr servers to call the robot squirrels running the Upcoming API and ask for the name of the Upcoming event with ID 2413636.

Upcoming then answers back and says: That event was called “Flickr Turns 5.25” and we store the title in our database. The next time you load that photo we’ll show a little Upcoming icon and the name of the event in the sidebar.

To date, we’ve only had machine tags “extras” available for upcoming:event= and lastfm:event= tags but starting today we’re adding support for three new projects: Dopplr, Open Plaques and the Open Library.


Dopplr is a social travel site which recently launched a Social Atlas to allow their users to create and share lists of interesting places, in the cities they know about, of where to eat and stay and poke around during their visit.

“Over time, we can anonymise and aggregate all the recommendations that have been added to Dopplr. This is the Social Atlas itself, something that’s greater than the sum of its parts: a kind of world map representing the combined wisdom of smart travellers. It’s early days still, but we are very excited by its potential.”

Which is pretty exciting, especially when you think about how many pictures of delicious food people upload to Flickr!

Dopplr/Flickr machine-tagging

photo by moleitau

You can add Social Atlas machine tags to your photos by tagging them with either "dopplr:eat=", "dopplr:stay=" or "dopplr:explore=" followed by the short-code for that place.

For example, dopplr:eat=tp71.

Dopplr's closed the loop: Machine-tagged flickr pix on their 'Social Atlas'

photo by moleitau

As an added bonus every single page in the Dopplr Social Atlas displays the complete machine tag you need to tag your photos with so you can just copy and paste the tag from one page into the other and your photos will be updated like magic!


The Open Plaques website is a community-run website set up to catalogue and document the many blue plaques that are hung across the UK to commemorate persons and famous events.

Frankie Roberto, one of the people behind the project has written often about the project, and the motivations behind it so rather than try to paraphrase I will just quote him (at length):

“With these in mind, I was thinking how this kind of ‘mobile learning’ might apply to the heritage sector, and as you might have guessed from the title, thought of blue plaques. You see them everywhere — especially when sat on the top deck of a double decker bus in London — and yet the plaques themselves never seem that revealing. You’ve often never heard of the person named, or perhaps only vaguely, and the only clue you’re given is something like “scientist and electrical engineer” (Sir Ambrose Fleming) or “landscape gardener” (Charles Bridgeman). I always want to know more. Who are these people, what’s the story about them, and why are they considered important enough for their home to be commemorated?”

Getting information about blue plaques on your mobile phone…

Picture 7

“The final step towards making this more compelling was to add some photographs. Here, Flickr came to our rescue. There was already a ‘blue plaques’ group, which contained hundreds of photos. To link them together, I used special tags called ‘machine tags’, which are like normal tags except that they contain some slightly more structured data. It’s very simple though — each plaque on the Open Plaques website has an ID number (which can be found at the end of the URL), and the corresponding machine tag for that plaque is openplaques:id=999 (where 999 is the ID number). Another script then uses the Flickr API to find all the photos tagged with a relevant machine tag, checks to see if they are Creative Commons licenced, and then to displays them on the Open Plaques website, with a credit and a link back to the Flickr photo page.”

Open Plaques project update

So, we did the same! If you have an openplaques:id= machine tag on your photo then we’ll try to look up and display the inscription for that plaque.

You can add Open Plaques machine tags to your photos by tagging them with "openplaques:id=" followed by the numeric ID for a specific plaque.

For example, openplaques:id=1633.


The Open Library is a part of the Internet Archive whose mission is to create a “web page for every book ever published.” To do that they’re hoping that anyone and everyone will participate and help by adding information they have a published work or a particular edition.

“After almost fifty years of computerizing everything, we’re realising now that the stories have gone, and we need them back — the handicraft, the boutique, the beauty, the dragons, the colour of stories. I’m reminded of the gorgeous mysterious early maps of the Australian coast. The explorer only got so far, and the cartographer could only draw so much. Much more exciting than boring old satellite, top-of-a-pin’s-head accuracy! I love the idea of trying to catch some of these dog-eared tales within Open Library.”

George Oates

As it happens Flickr users have created over 900 groups about book covers and a casual search for the phrase (“book covers”) returns 98, 000 photos!

Back in July of 2007 Johnson Cameraface uploaded a photo of the cover of ROBOTS Spaceships & Other Tin Toys”. Two years later, George asked if it would be alright to use the photo to update the Open Library record for the book, and added an openlibrary machine tag along the way.

Now, starting today, the photo page now displays the title of the book and links back to the Open Library!


This makes me happy.

You can add Open Library machine tags to your photos by tagging them with "openlibrary:id=" followed by the unique identifier for that book.

For example, openlibrary:id=OL5853184M.

It’s worth noting that the unique identifiers for Open Library books are sometimes a bit of a treasure hunt; they are the letters and numbers that come after openlibrary.org/b/ and before the book title in the URL for that book. Like this:


But wait! There’s more!!

Approaching zero

Did I mention that we have over one million photos tagged with Last.fm event machine tags? That makes it kind of hard to know when new machine tags have been added because lopping over all those tags just to find recent ones is expensive and time-consuming.

To help address this problem we’ve add a shiney new API method called:


This does pretty much what it sounds like. Given a namespace or a predicate (or both) and a Unix timestamp, the method returns the values for those machine tags that have been added since the date specified.


This entry was posted in Uncategorized and tagged , , by Kay Kremerskothen. Bookmark the permalink.

About Kay Kremerskothen

Kay is a Community Manager for Flickr and passionate about extraordinary photography. As an editor on Flickr Blog he loves to showcase the beauty and diversity of Flickr in his posts. When he's not blogging or making Flickr more awesome (in front of and behind the scenes), you can find him taking pictures with his beloved Nikon and iPhone, listening to Hans Zimmer's music or playing board games. | On Flickr you can find him at https://flic.kr/quicksilver