Innovative way of Flash Virtual Interaction System using laser pointer

Preamble:
This project proposes a cost-effective solution of interacting with a projector screen using a laser pointer, via an ordinary webcam.

The system was deployed and scripted in Flash Actionscript 3.0, back in Dec 2007 to Jan 2008.

It subsequently won the Most Innovative Award and Best Exhibit at the Singapore Shell Science Fair 2008, was shortlisted by MOE to represent Singapore in the Taiwan International Science Fair (TISF) 2008, in addition to being an exhibited finalist at the A*STAR Singapore Science and Engineering Fair (SSEF) 2009.

For more information, please checkout http://blog.joeltong.org/ .


Method:
The system comprises of a screen image from a projector. A webcam is positioned to track the projector screen area.

The steps for successful detection are as follows:
1.Calibration - 4 Red dots are shown on-screen. Thresholding red, the system is able to pick out the distance between the four red dots, demarking the tracked active area by the webcam. A ratio is then computed which is used to position the mouse.
2.A red laser dot is then shone onscreen. Minor adjustment knobs compensate for the offset in terms of the computed position of the laser dot and its actual position, similar to zeroing in using a crosshair.
3.The system is ready to track the laser pointer. In this case, a much high threshold is used, from the fact that red laser beams have a much higher intensity from the surrounding background.

System has been shown to detect laser dot despite showing red noise. However, alternative algorithms are being devised fo9r the system for better background noise tolerance.

Do checkout the version shown at Shell Science Fair @ http://www.youtube.com/watch?v=Bzpfgc-j8TM. System is targeted at rhe Flash platform, and for home users.

For more enquiries,

Email: me {at} joeltong {dot} org.

Thanks!


Best regards,
Joel Tong
http://blog.joeltong.org/

Category:

Science & Technology

Tags:

• Joel Tong
• Tong Haowen Joel
• AS3
• Actionscript 3
• Flash
• joeltong.org
• thresholding
• SSEF
• TISF
• Shell Science Fair
• Singapore
• laser pointer
• Temasek Junior College