1. Introduction
Face Recognition Systems (FRS) have consistently ex-hibited vulnerability to morphing attacks, which under-mines the reliability of face biometric systems widely utilized in secure access control applications. NIST Face Analysis Technology Evaluation (FATE) Morph [16] indi-cates that the higher the accuracy of FRS, the lesser the resistance to morphing attacks. Morphing is the process of blending multiple facial images to generate a compos-ite image that displays the texture and geometric features of source images. Given its complexity, it is difficult to distin-guish morphed images from skilled human observers, such as border guards [11], as well as automatic detection sys-tems [16].