Self-embedding watermarking method for G-code used in 3D printing

Abstract

3D printing is faced with a lot of security issues, such as malicious tampering, intellectual property theft and so on. This work aims to protect the G-code file which controls the 3D printing process by proposing a self-embedding watermarking method for G-code file. This method groups the G-code lines into code blocks and achieves a random mapping relationship for each code block. Each code block is divided into two parts, carrying the authentication and recovery bits, respectively. The tampered regions are detected by leveraging the authentication bits in each code block. Meanwhile, the G-code files are restored based on the recovery bits and the geometric information of the neighboring code blocks. Experimental results indicate that the proposed method can effectively detect the tampered region and restore the G-code file to a large extent, while limiting the distortion caused to the 3D printed object by the watermarking.