A 3D Facial Reconstruction Evaluation Methodology: Comparing Smartphone Scans with Deep Learning Based Methods Using Geometry and Morphometry Criteria
Álvaro Heredia-Lidón, Alejandro Moñux-Bernal, Alejandro González, Luis M. Echeverry-Quiceno, Max Rubert, Aroa Casado, María Esther Esteban, Mireia Andreu-Montoriol, Susanna Gallardo, Cristina Ruffo, Neus Martínez-Abadías, Xavier Sevillano
TL;DR
The paper addresses the challenge of validating low-cost 3D facial acquisition and reconstruction methods by introducing a geometry-plus-morphometry framework. It combines traditional geometric metrics with geometric morphometrics ($GPA$ and $EDMA$) to quantify global and local shape preservation, using stereophotogrammetry ($SPG$) ground-truth models. In a case study, smartphone-based scans and deep-learning reconstructions from 2D images are evaluated against SPG, revealing that smartphone scans generally better preserve facial morphology than the DL reconstructions, though static capture limits practicality. The proposed methodology provides a robust, biology-informed validation tool that can guide improvements in low-cost facial imaging technologies for clinical applications.
Abstract
Three-dimensional (3D) facial shape analysis has gained interest due to its potential clinical applications. However, the high cost of advanced 3D facial acquisition systems limits their widespread use, driving the development of low-cost acquisition and reconstruction methods. This study introduces a novel evaluation methodology that goes beyond traditional geometry-based benchmarks by integrating morphometric shape analysis techniques, providing a statistical framework for assessing facial morphology preservation. As a case study, we compare smartphone-based 3D scans with state-of-the-art deep learning reconstruction methods from 2D images, using high-end stereophotogrammetry models as ground truth. This methodology enables a quantitative assessment of global and local shape differences, offering a biologically meaningful validation approach for low-cost 3D facial acquisition and reconstruction techniques.
