The CityWall is a large mutli-touch display installed in a central location in Helsinki which acts as a collaborative and playful interface for the everchanging media landscape of the city.
It uses a non ftir technique which works in broad daylight or at night. It works when the creen is dirty or clean and has the added advantage that not just points of contact are seen and processed resulting in information about hand postures making possible more advanced gestures.
That looks really cool. Nice to see you’ve made it sms interactive, this was one of the first features i thought of when first seeing the photo apps for the first time, i was really puzzled why this hasnt been included in an commercial installation yet.
I get how it works at night, but during the day do the users hands cause big shadows since they are being lit from behind? Is the same kind of image processing going on for day and night? or does it look for shadows during the day, and highlights during night?
Thanks. We have been working on collaborative media applications for quite some time so TheWall (the name of the technology) was designed from the ground up to supports such things. Right now we are still at a really basic stage with everything application wise; which is changing even as I type this.
In terms of the technology I can say that we do use two differnt techniques for the day and night It is the only way to make anything approaching robust.
Hey John, First I would like to thank you for posting your works here, absolutly stunning. I never thought you could get so much response out of a near-infrared installation, your Tip Detection seems to work very well. I really enjoyed your “pen gesture” & keyboard toggle, very user friendly.
What software platform did UIX develope this on? I would imaging C++, also would you guys ever consider collaborating with some of the group members to add features to the wall?
If this is not considered FTIR then what would this tech be considered? This is very interesting and seems to have advantages over FTIR. From watching the video I noticed you were using an IR emitter. I will admit I know little to nothing about these. Could anyone explain? What does it consist of and how well does it work? This seems to be step 1 in allowing a day/night display. At least thats what my limited knowledge on the subject tells me. Is this similar to what Jeff Han uses on his large wall display? Other then the IR emitter and obviously some unique work on the software side I don’t see anything out of the ordinary. If thats all it would take to make a more functional multi-touch display then I have to question why more people aren’t taking this route. Of course I’m probably missing something.
CityWall (at night) is similar to the reactable setup. The reflection method (thats what i call it, does it have a more officail name?) offers several advantages to FTIR once you have got good software and calibration.
I think that this is actually still FTIR, how else would you account for such well-defined edges? The difference in this method (for me, at least) is the reduced contrast from the flood lit approach. It makes for an easier design maybe, but without the contrast, “blob detection” is replaced by “edge detection” which probably requires a bit more processing power, and definitely more complicated algo’s.
But the advantages then are more control over things, such as hand position, and other gestures. But, you could probably do similar with blob detection, just in different ways with different software. I would venture to say, just from contrast alone, that blob detection would be more *certain* but edge detection to be more *expressive*. Or I’m just full of it. ;p
Yep… even after the MS Surface buzz of today, CityWall is quite impressive. And at least has as much, and even more potential than the 30” table top.
So far as I understand, we have been using a similar principle (as Uix group does for CityWall) for our framework.
For sure it not as well crafted and developed as “TheWall”, but come on … we are only two ….We focus on the performative relations that occur between co-located individuals mediated by an interface. We called this framework “Performative Surface”. Its goal is to emphasise the intensity of interaction by way of a two side responsive surface.
Ps: have been working on a Multi-touch “table” interface since a while now … leClone [ http://www.smallfly.com/interactivesystems/leclone.html ] was the first proto – more than a year ago… I will soon post info about the current version we are working on.
All I can say is WOW!! That is so freaking cool. Excellent job to those who made the CityWall happen! Someone please explain in detail how the daytime illumination works and how the system selects (and decides) between day/night - front/rear illumination. Also, any chance there will be system details or software released?
A quick note of some details that they use edge-detection versus blob-detection. There is some support inside of OpenCV for such a thing, but raw code or new code pertaining to nuigroup is forthcoming… it seems like I got wind that someone has it working with VVVV? Myabe not just yet…
I haven’t time yet to post something on my website but you can find here some of the photo of the multi-touch interface I’m working on.
http://www.flickr.com/photos/smallfly/
It is the only way to make anything approaching robust.
….We focus on the performative relations that occur between co-located individuals mediated by an interface. We called this framework “Performative Surface”. Its goal is to emphasise the intensity of interaction by way of a two side responsive surface.
