An Error-Correcting Code-Based Robust Watermarking Scheme for Stereolithographic Files

Abstract

Stereolithographic (STL) files have been extensively used in rapid prototyping industries as well as many other fields as watermarking algorithms to secure intellectual property and protect three-dimensional models from theft. However, to the best of our knowledge, few studies have looked at how watermarking can resist attacks that involve vertex-reordering. Here, we present a lossless and robust watermarking scheme for STL files to protect against vertex-reordering attacks. Specifically, we designed a novel error-correcting code (ECC) that can correct the error of any one-bit in a bitstream by inserting several check digits. In addition, ECC is designed to make use of redundant information according to the characteristics of STL files, which introduces further robustness for defense against attacks. No modifications are made to the geometric information of the three-dimensional model, which respects the requirements of a high-precision model. The experimental results show that the proposed watermarking scheme can survive numerous kinds of attack, including rotation, scaling and translation (RST), facet reordering, and vertex-reordering attacks.