PiCode

Abstract

As 2D barcodes become more and more popular, their new applications, like mobile marketing, give a strong motivation for embedding visual information in them. Information stored on a 2D barcode, being printed on paper or shown on a display device, can be delivered to people via a camera phone with suitable decoding software. The barcoding system can be viewed as a communication system with key functional modules, including channel coding, modulation, channel estimation, demodulation and channel decoding. By applying advanced communications principles, a way to integrate a picture into a 2D barcode (called PiCode) is developed. By extending the idea, a way to integrate a video into a series of 2D barcodes, called ViCode, is also developed. To realize PiCode and ViCode, new modulation and demodulation schemes are designed. Based on our channel estimation technique, a new decoding scheme for low-density parity-check (LDPC) codes is devised to provide more robust error rate performance than traditional 2D barcodes. A US patent and a Chinese patent have already been filed based on the innovative methods developed for PiCode.