LED Light Stick

By Stefano Barbier


A one meter long strip of 60 neo-pixels is connected to an Arduino Uno and a
portable battery to recreate images with a long exposure camera. Images can either
be downloaded online or created in Adobe Photoshop. Images are compressed to 60
pixels high, while maintaining proportional horizontal dimensions, and exported as
a JPEG. This JPEG is read in a Java program (written in Eclipse Neon), which exports
a text file with each pixel’s color as one element in a long list. Each pixel in the JPEG
image is converted to its’ binary RGB representation and then color mapped to the
rainbow colors (ROYGBIV). The outputted list is copy and pasted into an Arduino
IDE script and saved in flash memory. The script reads the list in 60 element chunks
and flashes them to the LED stick. A camera on a tripod is set up with an exposure
time of around ten seconds. A user walks across the frame while holding up the LED
stick during the duration of the exposure.

Report (pdf)

JPEG reader

Color function

Arduino controller