Nice Banners

Quakr front page had a bit of a face lift at the weekend. It now links directly to a current release version of the Viewr and notes some news which may be of interest. Hope you like it.

Meanwhile, we've been furiously writing up the talk we gave to SWIG in order to present it to XTech as a paper. The deadline is next week so ... we've got ages!

Those nice business cards arrived safe and sound so we'll be palming them off on all and sundry over the coming weeks and months. And we've also been beavering away at a bunch of things we thought were wrong with the most recent incarnation of the Viewr. Expect a release soonish...

and suddenly a card appeared

Soon you'll get the opportunity to own one of these lovely things in reality. Aren't you lucky. And if you click through to the people who are making them for us, Vista, you'll get 25% off.

A 2nd gig to follow SWIG

Quakr is most proud to announce that it managed to stand up in front of the uber geeks that are SWIG and make their *thing* make sense. The 20 allocated minutes were split into three basic parts - an intro, a demo and a SWIG specific ending. This seemed to work. We're thinking that the article for XTech may well follow these lines.

If you were there and want a recap, or weren't and want to know what we said, http://www.quakr.net/~katie/SWIG has all the links we used. It doesn't have a copy of the words we said, but hopefully it covers the gist of the talk.

On the back of what seemed to us to be a well received talk and post-talk-public-house discussion, we've got a second "gig". This time it's locally run Oxford Geek Night to be held on the 11th April. See you there!

related or relevant, 03/07

- Nokia phone with tilt/accelerometers
here

- Quakr to talk at SWIG
here

- new Quakr Viewr "home"
here

-- more --

- Geograph - claim your map square by taking a picture! Rival project?
here
- They have a lat/long to other convertor...
here
- And on upload ask what direction the photograph was taken, where the photgrapher was and where the main subject of the photograph was (surely one of these three could be implied?)
- and I noticed that Flickr "Place this photo on a map" link takes you to a page with a map and the text... "We've put the photo into the Findr for you (below). All you have to do now is drag it onto the map!"

-- more --

- GoogleMaps - "Photos on Google Maps"... well kind of...
here

-- more --

- Nokia Imaging Zone...
here

- Nokia - smart phones save lives?
here

- possible Quakr card?
here

- "Geowanking" discussing the geo:alt measurement problem...
here

-- more - post SWIG --

- Goniometer... an angle measurement device.
here

- Oxford Metrics Group - The Group trades through three operating subsidiaries – Vicon, the world’s biggest motion capture and movement analysis company, 2d3, a manufacturer of specialised image understanding software for entertainment and defence applications and Geospatial Vision, our 3D mapping business.
here

- A second gig at the Oxford Geek Night
here

- image analogies
here

- photsynth now in firefox...
here

-- more --

- Google's sketchup used to make oxford
here

Flickr API - features and foibles

This week, I've been working on the flickr communications side of the Quakr Viewr app.

Semantically sensible
I've found the Flickr REST API fast, simple, and very well documented - incomparable to the befuddling eBay services docs I worked with last year.

The search API does wot it says on the tin. A GET Request for:

http://api.flickr.com/services/rest/
  ?method=flickr.photos.search
  &api_key=[your key]
  &tags=tin

, gives back a semantically sensible piece of XML metadata, with a list of elements named <photo>. By concatenating the bits in the right order, you can make the URLS of the photos themselves.

Cool things
Cool thing 1: &bbox=
The most exciting aspect of the Flickr API from our Quakr perspective is support for bounding box searches, meaning that we can give four geo:lat/long coordinates, and get back sets of photo metadata.

As a pedant, I must point out that, before the fanfare, Flickr already "supported" geotagging in that it supported whatevertagging - people were merrily adding geo:long=1234, and Flickr were letting people query it. What is new is that Flickr have started splitting the machine tag at the equals sign, treating 1234 as a number, stuffing it into some special database AS a number. Suddenly, they can do MATHS, and support COMPARISON operators, and presto, offer bounding box searching.

Cool thing 2: &extras=
The &extras optional parameter on a search causes extra metadata to be returned in the results. For Quakr, we're going to be using tags like ge:tilt for 5 of the 7 in our 7D metadata, so we need to get at these tags, and, for good user experience, to get at them quickly (ie, without making lots of extra requests.) extras=machine_tags is just the job.

Foibles
One or two features which confused me at first:

Foible 1: backdata
Geotags that were entered before the geotagging 'release' aren't imported into the special database. From the groups:

"# What about all the machine tags that are already in the Flickr database?
At the moment, they are still treated as plain old tags. We have plans to go back and re-import them as machine tags but for now, only new tags will be processed as machine tags."

The solution is given in the same post:
"In the meantime, if you re-save a machine from the 'edit this tag' page it will be re-imported as a machine tag."

Foible 2: 'limiting agent'
From the search docs:
"Geo queries require some sort of limiting agent in order to prevent the database from crying.
...If no limiting factor is passed we return only photos added in the last 12 hours (though we may extend the limit in the future)."

I solved this, following guyfisher's advice, with a

&min_taken_date=1970-01-01%252000%3A00%3A00

. (I'm OK with the start of time in viewr being the unix epoc...)

Quakr presentation at XTech 2007

We, the Quakr gang will present our musings on Thursday 17th May at XTech 2007 in Paris, France.

Now... whether to have one of those presentations that consist of random colourful photos (creative commons, naturally), with just one word in white in the corner? Or is that just sooo 2005? Or, like flares, has it come around in a circle... ?

OK, I think what we'll do is put the viewr on autopilot on the screen behind us. I find walking through the floor and into the white void particularly vomitous.. perhaps we can set a record for mass induced motion-sickness...?

------
viewr:

a place to stand

“GIVE ME A PLACE TO STAND AND I WILL MOVE THE EARTH” said Archimedes.

In thinking about moving the Quakr Viewr camera in a nice smoothish and less jumpy way, I suddenly hit upon what has been a philosophical problem for many years. In the Quakr Viewr world, there is no difference between moving the world and moving the camera. Imagine standing up from your seat - there is no way to satisfactorily differentiate between your head moving upwards and the world moving downwards. They both result in what your eyes see and the both result in what your mind perceives. It's only when we start thinking about everyone else who is standing up at the same time that the conclusion that the world is NOT moving but we ARE becomes the sensible one.

In Quakr Viewr I initially coded the camera to move when the user hits buttons or presses keys. When a user clicks on an image in view, selects an image from the drop-down list, or hits the previous or next buttons, the camera moves to the *best view* position for that image. Initially, it jumped to that position, but in the most recent release, it first jumps to look at the image and then moves smoothly through 20 iterations from it's current position to the aforementioned *best view* position. This is done by *simply* moving the camera, but I did investigate the possibility of moving the world. The two overly detailed reasons for this investigation were a) the sandy flash engine may work quicker with object moves instead of camera moves and b) there is more iterative move options available for object moves in the engine.

After much typing, testing and re-releasing, I found that there is no significant speed difference, but the complications of remembering where the world has been transformed to, and thus where it has to go next proved to be too much headache for me. The current release uses something Sandy Flash calls a *positionInterpolation* to control the camera position, and you'll notice that there is a bit of a jump before the movement starts as I flip what the camera is *looking at* (I'll be working on that if I find some spare time!). It's all good and here.