Morphing is a well-researched topic in computer graphics and image processing. Unlike cross-fading, morphing transforms a source image into a target image using distortions and the adjustment of predefined features (control points). This transition is intended to create results that are as realistic as possible, and it happens notably when the face on the source and target images does not differ too much. Therefore, the typical morphing process consists of warping essential image elements (e.g., facial features such as eyes, mouth, and facial contours) in the source and target image with the help of selected control points in such a way that these areas can be brought into conformity with each other or align themselves. For effects as close to reality as possible, the source and target images must not differ too much. The training course developed for this work is intended to introduce the dangers posed by the malicious manipulation of facial photographs, the so-called morphing attack. An algorithm matches the images of two different people so that the resulting facial image combines the identification features of both people. Research has shown that these images are difficult for the human eye to distinguish from real, unaltered photographs. The face morphing attack exploits the weakness in the application for identification. If a morphed passport photo remains undiscovered, a genuine identity document with a manipulated photo is issued that may allow two different persons to cross a border without authorization. This targeted training course consists of 10 modules for a one-week training course and is designed to help identify morphed facial images and reduce their acceptance at ID and passport control.
Franziska Schwarz, Klaus Schwarz, Reiner Creutzburg, "Improving detection of manipulated passport photos - Training course for border control inspectors to detect morphed facial passport photos - Part II: Training course materials" in Electronic Imaging, 2022, pp 361-1 - 361-8, https://doi.org/10.2352/EI.2022.34.3.MOBMU-361