3 posts tagged “location”

When I posted about lib-flickr-minimal, I noted that the newly-launched flickr.places.placesForUser method made a more interesting demo of data you could fetch when authenticated than, say, showing a user's most recent private photos. Evidently the developers at Flickr agreed it was an interesting concept, because over the last couple of months that area of the API has been extended considerably, As a result, I've expanded the demo into an AppJet application of its own.

Where? What? When? is the result. It shows you, on a map, the locations with the most photos according to a given criterion: by default, that's a tag, but it can also show your photos, or those from your friends and family, or your contacts. You can then inspect a place and see the most recent relevant photos, or the most popular tags, for that location.

How did that evolve from the initial demo app? Instead of simply printing a table based on Flickr's response into the document, I directly plotted the results on the map. I added a small form to enable the choice of criteria, and when Flickr added the placesForTags method, I added that as a choice. Belatedly, I realised that would also work for users without authentication, so I removed the requirement to authenticate, and made tags the logged-out default. (The image above shows a slight change to the initial results: it's the same tag, London, but at the neighbourhood, not locality, level. All of the locations are within the greater city's area, which probably won't be a surprise, but that's not true for Paris. Evidently, what happens in Vegas doesn't always stay there.)

The design of the application isn't quite settled, but I knew I wanted to replace the standard Google Maps pushpins with partially-transparent circles. Initially, I went with red, but when I showed it to colleagues, they said it reminded them of maps of bomb blast radii, so I spent a while looking around for the right colour, before settling on a yellow. The circles themselves are scaled according to the natural log of the number of photos for that location; I played with square roots as well, but I feel that logarithms give the right sense of scale.

The last piece of work I did was adding tag display for locations, using the tagsForPlace method. These tags can be surfed: clicking on one will load a new search for the given tag. It's noticable that the first few tags for most places are almost always place names, while common tags seem to share a familiar pattern of scattered, similarly-sized circles across the US, Europe, south-east Asia and coastal Australia.

There's still a few things I could add; tag persistence in URLs (to make it easier to share pages), better loading indicators (especially initially), options on which photos are shown, and links to view the search on Flickr itself, for example. There's also a missing question: while the API methods support maximum and minimum times, I haven't yet added options to allow you to show When? However, for now I think I've done enough (and I'll note that the site has a link to view the source of the application, if you fancy hacking on it yourself.) Enjoy.

Having finally got snaptrip out there, I'm hoping you'll allow me a little (pretentious?) waffle about why I wrote it, where it fits, how I made some of my decisions, and what's next.

I'm a big fan of Flickr's machine tags. Most of my images have at least ten - mostly generated automatically, like my EXIF machine tags - and I tend to add geographic metadata as well. As such, it's probably not a surprise that I'd write an application that made Dopplr trip IDs available. The big surprise is that I bothered to make it accessible to most people, by building it as a website not a script.

Why a website? Well, I thought I'd like a nice interface as much as anyone, and I also know that to make a machine tag truly useful you need as many people as possible using it. Asking folk to download a script, get a key, and use a command-line interface - or no interface at all - isn't going to work.

Speaking of Dopplr, I don't think I've seen a talk by anyone there since it started, but I do think I've picked up their philosphy from slides and abstracts online. The phrase that tends to crop up is a "coral reef", the idea being there's a web of data that's available on the internet and that by doing one thing, and doing it well - the old Unix philosophy, really - that you can live in a happy niche. Well, snaptrip lives on part of the coral built by the two companies whose API it consumes.

I'm not under any illusions: it's likely that most users won't care about their past trips, or matching their Flickr photos. Those who do will probably only visit the site once, tag a few trips, and then leave. That's fine.

In my previous post I alluded to some decisions I made about the geotagging features in snaptrip. To be honest, it wasn't something I'd considered at first, but seeing Richard Crowley's Dopplroadr hack - which does some of the same things as snaptrip, but when they're uploaded rather than by looking for existing Flickr photos - made me consider the possibility. However, because I am looking at things that have probably accumulated metadata already, snaptrip is careful not to overwrite any information that's already there.

snaptrip adds fewer tags than Dopploadr. It won't add human-readable tags at all, and it adds the geographical data at a relatively low level of accuracy. I didn't want snaptrip to assert with precision that all these photos were taken dead in the centre of Copenhagen, since they probably weren't. My US trips show exactly the sort of thing I'm talking about: most of my pictures are actually taken anything from ten to two hundred miles from where Dopplr thinks I was staying. Similarly, it doesn't set a woe:id machine tag, instead preferring to use the dopplr:woeid namespace/predicate pair.

It's quite possible I'm overdoing the paranoia here, and so I'll probably add the option to set more tags later, but for now, I'm happy to tread lightly. (In that vein, snaptrip doesn't set a visible "snaptrip" tag, like many apps (Shozu and AirMe spring to mind; Picnic also suggests adding its tag). However, it does set a dopplr:tagged=snaptrip machine tag, and I should probably make that optional also. For now, you can use Flickr's tag tools to delete it.)

So, what's next? Well, the basic functionality I wanted seems to be there and stable, so I'm now considering two further avenues. I'm trying to develop tools to give you some views on the aggregated data from your past trips, but perhaps I should instead be looking at tools to increase the amount of stuff in that Dopplr history. I've got a couple of ideas...

Just a quick note to say thanks to all of you who've been using snaptrip today, since it was mentioned on DopplrHQ's Twitter stream. As it says in the questions and answers on the front page, I'm still poking at lots of bits of functionality, and you may see the odd error when I haven't properly caught one of the web services I use failing to send back some text. Despite all that, I can see that the app's been fairly popular, and hopefully it's been useful.

However, I've just spent an evening tightening up some of the text, and also working on how to show that an image already has either Dopplr trip tags or location data. (You've probably noticed there's a link that doesn't work- I didn't expect to be releasing quite so soon- but it might give you a clue as to what's coming next.) I'll try and keep posting fairly regularly, but for now, thanks again.