INCREASING THE CAPACITY OF COLOR PRINT CODES FOR ROBUST COMMUNICATION OVER INKJET PRINT-SCAN CHANNELS

摘要

This investigation on robust and high capacity print codes aims to increase information payload in a given printed page area while providing robustness to channel errors including distortions originated by the inkjet printing and scanning processes. The approach includes statistical print-and-scan channel characterization, designing of robust segmentation using visual cues, unsupervised Bayesian color classification with expectation-maximization algorithm for parameters estimation of a mixture of Gaussians model and design of error correction codes. Results illustrate the performance evaluated under real channel and distortions conditions. High payload of 4592 bytes per squared inch is achieved with a robustness of 92% to distortions due to the print-and-scan channel. Adding high-density information to printed materials enables interesting hardcopy document applications involving security, authentication, physical-electronic round tripping, item-level tagging, and consumer/product interaction.