Unbreakable QR Code Watermarks: A High-Robustness Technique for Digital Image Security Using DWT, SVD, and Schur Factorization. - Bashar Suhail Khassawneh; Issa Al-Aiash; Mahmoud AlJamal; Omar Aljamal; Latifa Abdullah Almusfar; Bashair Althani; Waad Aldossary (Cryptogr., 2025)