imaging as an alternative data channel for camera phones
In this paper, we demonstrate a solution to use cameras to down-load data to cell phones as an alternative to existing wireless (CDMA/GPRS, BlueTooth), infrared or cable connections. In our method the data is encoded as a sequence of images, which can be displayed on any flat display, captured by users with their camera phones, and decoded by pre-embedded software. To solve this problem we need to be able to (1) encode arbitrary data as a sequence of images, (2) process captured images under various lighting variations and perspective distortions while maintaining realtime performance, and (3) decode the processed images robustly even when partial data is lost. In the paper we address these challenges in detail and present our solution. We have implemented a prototype which allows users to successfully download various types of files, including pictures, ring tones and Java programs to the camera phones. We discuss the limitations of our solution, and future works to overcome these limitations.
camera phone image decoding error correction