3D craniofacial reconstruction framework using elastic surface deformation based on automatic landmark positioning

Computer-aided craniofacial reconstruction (CFR) is a process that aims to estimate facial impressions based on skull remains. It mimics the conventional method with a conceptual model-based framework. The existing problems in CFR are that landmark annotation is expert-dependent, landmark processing in the 3D domain has volumetric challenges, and a method based on a population's morphological characteristics (templates). A framework with three stages is proposed: Building a craniofacial model, automatic landmark detection, and surface deformation. Machine learning is deployed to draw local surface correlations as landmarks and automatically detects their position. The local surface context is extracted using the Surface Curvature Feature (SCF) as a 3D descriptor. Using a cluster-based filter, the average distance (to the ground truth) of the top 20 points is 0.0326 units. Cluster-based filters are better than mass-radius-based filters and consistently give better pinpoint accuracy, especially in multi-cluster cases. Training data consists of 140,000 SCF for ten landmark classes. The third stage, surface deformation, fits the facial template to the cranial based on the corresponding facial-cranial landmarks. Five experts from the Anthropology department stated that of the reconstruction results, 91.5% could retain the template details and are accepted as the natural shape of the human face.