De-identification and restoration methods for protecting privacy in off-line documents

Abstract

The necessity of protecting personal information contained in off-line documents (e.g., identification cards, driver's licenses, passports, and delivery invoices) is increasing as the subject of privacy is expanding to various objects in the physical world from the existing security perspective, which was limited only to on-line services. In this paper, we propose off-line document protection technology that can safely protect ID cards and important confidential documents released with personal information exposed on the website, and prevent cases where personal information (name, address, phone number, etc.) on delivery and mail is leaked and abused in the crime. The proposed method consists of masking and unmasking process using two-dimensional bar codes and a user’s secret keys. Through the experimental results using the proposed method, we confirmed that personal information in off-line documents can be changed as an unreadable form and that only authorized user can restore the unrecognizable area to prevent the leakage of personal information.