Edinburgh Napier University

  Facial composites are pictures of human faces.
These are normally constructed by victims and witnesses of
crime who describe a suspect’s face and then select
individual facial features. Unfortunately, research has
shown that composites constructed in this way are not often
recognised. In contrast, we are quite good at recognizing
complete faces, even if the face is unfamiliar and only seen
briefly. This more natural way of processing faces is at the
heart of a new composite system called EvoFIT. With this
computer program, witnesses are presented with sets of
complete faces for selection and a composite is ‘evolved’
over time. The current work augments EvoFIT by
developing a set of psychologically useful scales – such as
facial weight, masculinity, and age – that allow EvoFIT
faces to be manipulated. These holistic dimensions were
implemented by increasing the size and variability of the
underlying face model and by obtaining perceptual ratings
so that the space could be suitably vectorised. The result of
three evaluations suggested that the new dimensions were
operating appropriately.