MultiTouch

Intro

to see the full image at flickr click it

I am working on a multitouch screen with a friend. Sure M$ and Apple and some other big names are doing it too but it's actually pretty easy so go build one too.

Photo Viewer

updated with touchlib

This application has been updated to use touchlib and runs much faster since touchlib is better suited to this than opencv's blobtracker. It also supports pretty much any image (converted to a bitmap for texture mapping in opengl at runtime).

The newest version of this app is using rigid body dynamics to allow an arbitrary number of fingers move, scale, or rotate an image. This interface is much more intuitive nad robust since fingers can drop out of or join the touchmap without effecting the overall transformation to the image object.

initial test

At this point the photo viewer is a simple demo that loads 10 128x128 bitmaps in at runtime. To load an image onto the canvas I use a three point gesture. The image loads at the 3rd point. From there it can be scaled and moved about. You can only control the last image that was loaded because I haven't implemented a method to select an arbitrary photo yet. Stay tuned...

Single Photo Viewer

Here I've skinned the surface with an image and added touch position markers. You'll see the positional accuracy is still off but not too bad. Blob tracking response is still the weakest part of the system and I'm going to have to use something else soon.

Raw Camera Feed

This is the raw camera feed from my multitouch rig. You will notice the screen and camera feed do not map 1:1. This is corrected in software when manipulating objects in the front end.

Initial Front End Test

This shows translation and scaling of a simple object. The front end and back end aren't synced here so the cube drifts a bit. This is the first demo recorded on this new screen. I just built the rig (June 2nd) and have started to tie the front and back ends together and make something functional.

A Bit Better

This demo again shows translation and scaling as well as a gesture I made today. I'm not sure its useful yet but kinda fun. This video also shows the camera space and screen space a bit more tightly coupled. At the end of this video you see the app crash since there is a nasty memory leak in the blob tracking software I'm using.

-- ChristopherPepe - 03 Jun 2007