Towards a comprehensive 3D dynamic facial expression database

Human faces play an important role in everyday life, including the expression of person identity, emotion and intentionality, along with a range of biological functions. The human face has also become the subject of considerable research effort, and there has been a shift towards understanding it using stimuli of increasingly more realistic formats. In the current work, we outline progress made in the production of a database of facial expressions in arguably the most realistic format, 3D dynamic. A suitable architecture for capturing such 3D dynamic image sequences is described and then used to record seven expressions (fear, disgust, anger, happiness, surprise, sadness and pain) by 10 actors at 3 levels of intensity (mild, normal and extreme). We also present details of a psychological experiment that was used to formally evaluate the accuracy of the expressions in a 2D dynamic format. The result is an initial, validated database for researchers and practitioners. The goal is to scale up the work with more actors and expression types

Tell me again about the face: Using repeated interviewing techniques to improve feature-based facial composite technologies

Facial composite technologies are used to produce visual resemblances of an offender. However, resemblances may be poor, particularly when composites are constructed using traditional `feature' composite systems deployed several days after the crime. In this case a witness may have forgotten important details about an offender's appearance. Engaging in early and repeated retrieval attempts could potentially overcome this issue. Experiment 1 showed that more recognisable feature composites were produced after participants had provided detailed face recall during two supported retrieval attempts, which included instructions to reinstate the context in which the target had been seen, free recall and cued recall. The first recall attempt was completed on the same day as viewing the target individual, and the second two days later, and immediately before composite construction (traditional forensic procedure). Experiment 2 showed that repeated interviewing only incurred a benefit when the same day interview provided ample retrieval support. The results suggest how traditional forensic procedures can be easily modified to improve the quality of feature composites, and thereby facilitate the detection of offenders

Accuracy of relational and featural information in facial-composite images

Facial-composite images are crucial in helping to bring perpetrators to justice and thereby maintain national and international security. Psychology can assist in identifying the accuracy of such facial information as well as ways to improve their identification rates. The current experiment demonstrates that composites tend to differ in terms of their accuracy of featural information (individual facial features) and relational information (spacing between those facial features) depending on the type of composite software used. Composites constructed with feature systems tend to have more-accurate feature information, whilst those constructed with holistic systems tend to have more-accurate relational information. Further, it was found that not only the addition of sunglasses on poor-quality composites, but also viewing composites from the side, can increase their identifiability. This could be applied by the police to potentially increase identification and arrest rates of perpetrators

Applied screening tests for the detection of superior face recognition

open access articleIn recent years there has been growing interest in the identification of people with superior face recognition skills, for both theoretical and applied investigations. These individuals have mostly been identified via their performance on a single attempt at a tightly controlled test of face memory—the long form of the Cambridge Face Memory Test (CFMT+). The consistency of their skills over a range of tests, particularly those replicating more applied policing scenarios, has yet to be examined systematically. The current investigation screened 200 people who believed they have superior face recognition skills, using the CFMT+ and three new, more applied tests (measuring face memory, face matching and composite-face identification in a crowd). Of the sample, 59.5% showed at least some consistency in superior face recognition performance, although only five individuals outperformed controls on overall indices of target-present and target-absent trials. Only one participant outperformed controls on the Crowds test, suggesting that some applied face recognition tasks require very specific skills. In conclusion, future screening protocols need to be suitably thorough to test for consistency in performance, and to allow different types of superior performer to be detected from the outset. Screening for optimal performers may sometimes need to directly replicate the task in question, taking into account target-present and target-absent performance. Self-selection alone is not a reliable means of identifying those at the top end of the face recognition spectrum

Cross-age effects on forensic face construction

The own-age bias (OAB) refers to recognition memory being more accurate for people of our own age than other age groups (e.g., Wright and Stroud, 2002). This paper investigated whether the OAB effect is present during construction of human faces (also known as facial composites, often for forensic/police use). In doing so, it adds to our understanding of factors influencing both facial memory across the life span as well as performance of facial composites. Participant-witnesses were grouped into younger (19–35 years) and older (51–80 years) adults, and constructed a single composite from memory of an own- or cross-age target face using the feature-based composite system PRO-fit. They also completed the shortened version of the glasgow face matching test (GFMT; Burton et al., 2010). A separate group of participants who were familiar with the relevant identities attempted to name the resulting composites. Correct naming of the composites revealed the presence of an OAB for older adults, who constructed more identifiable composites of own-age than cross-age faces. For younger adults, age of target face did not influence correct naming and their composites were named at the same level as those constructed by older adults for younger targets. Also, there was no reliable correlation between face perception ability and composite quality. Overall, correct naming was fairly good across the experiment, and indicated benefit for older witnesses for older targets. Results are discussed in terms of contemporary theories of OAB, and implications of the work for forensic practice

Interviewing and visualisation techniques: Attempting to further improve EvoFIT facial composites

Victims of and witnesses to crime are asked to describe an offender using cognitive interviewing techniques (CI), before constructing a visual likeness of the face. The aim of the current experiment was to investigate whether composite construction using the EvoFIT holistic system would benefit from the parallel use of three enhancement techniques. The study manipulated the type of interview used to elicit a face description (CI vs. holistic cognitive interview, or H-CI) and trialled a visualisation technique for selecting faces (no visualisation vs. visualisation of external features). Also included was a new construction procedure for EvoFIT that requested constructors to focus on the region around the eyes when making face selections. Based on past research, it was anticipated that both the H-CI and external-feature visualisation would promote construction of a more identifiable composite (compared to when each technique was not used). Rather unexpectedly, the results revealed that neither technique improved correct naming of composites, yet an interaction was observed: visualisation of external features led to a benefit that approached significance when used in conjunction with the H-CI (cf. CI). However, when no external-feature visualisation was used, composites were better named following the more usual CI (cf. H-CI) protocol. Results are promising for the new method of face selection, which was used by all participants (focusing on the eye region). Indeed, in the baseline condition, where this was the only `enhancement' method used, naming of composites was 55% correct. Arguably, focusing on the character of the face during the H-CI may instate a processing style that is not well aligned with the new procedure of selecting faces according to the eye region. To overcome this misalignment of processing stages, we propose to ask constructors to focus on this region of the face during the H-CI itself. Implications for theory and police practice are discussed

The benefit of context for facial-composite construction

Purpose - The aim of this study was to investigate whether the presence of a whole-face context during facial composite production facilitates construction of facial composite images. Design/Methodology - In Experiment 1, constructors viewed a celebrity face and then developed a facial composite using PRO-fit software in one of two conditions: either the full-face was visible while facial features were selected, or only the feature currently being selected. The composites were named by different participants. We then replicated the study using a more forensically-valid procedure: In Experiment 2 non-football fans viewed an image of a premiership footballer and 24 hours later constructed a composite of the face with a trained software operator. The resulting composites were named by football fans. Findings - In both studies, the presence of the facial context promoted more identifiable facial composites. Research limitations/implications - Current composite software was deployed in a conventional and unconventional way to demonstrate the importance of facial context. Practical implications - Results confirm that composite software should have the whole-face context visible to witnesses throughout construction. Although some software systems do this, there remain others that present features in isolation and these findings show that these systems are unlikely to be optimal. Originality/value - This is the first study to demonstrate the importance of a full-face context for the construction of facial composite images. Results are valuable to police forces and developers of composite software

Taking research to members of the public

In 2006, with funding from the Engineering and Physical Sciences Research Council (£30k), we built a themed exhibit with the Sensation Science Centre in Dundee. In the main part of the exhibit, which was kitted out as a ‘police station’, a visitor would see a video of a man pretending to commit a crime and construct a composite of his face using a simplified version of our EvoFIT facial-composite system. Visitors were asked, using written and spoken prompts, to select faces from an array of alternatives, with selected items being ‘bred’ together, to allow a composite to be ‘evolved’. The exhibit then presented a picture of the man’s face alongside the evolved composite, example composites created by previous visitors and an average (‘morphed’) composite from the last four visitors. The exhibit took about five minutes for a user to complete and was accompanied by a ‘Research Lab’, a station which explained more of the underlying science: themes around evolution, computer-based generation of faces, forensic use of composites, etc. We expected the exhibit to last five years but, partly due to the robustness of the hardware, it remains today and is still popular

When age-progressed images are unreliable: The roles of external features and age range

When children go missing for many years, investigators commission age-progressed images from forensic artists to depict an updated appearance. These images have anecdotal success, and systematic research has found they lead to accurate recognition rates comparable to outdated photos. The present study examines the reliability of age progressions of the same individuals created by different artists. Eight artists first generated age progressions of eight targets across three age ranges. Eighty-five participants then evaluated the similarity of these images against other images depicting the same targets progressed at the same age ranges, viewing either whole faces or faces with external features concealed. Similarities were highest over shorter age ranges and when external features were concealed. Implications drawn from theory and application are discussed

Forensic procedures for facial-composite construction

Purpose – The paper provides a detailed description of standard procedures for constructing facial composites. These procedures are relevant to forensic practice and are contained in the technical papers of this special issue; the purpose of this paper is also to provide an expanding reference of procedures for future research on facial composites and facial-composite systems. Design/methodology/approach – A detailed account is given of the interaction between practitioner and witness for producing a facial composite. This account involves an overview of the Cognitive Interview (CI) and the Holistic CI (H-CI) techniques used to obtain a description of the face of an offender (target); the authors then describe how this information is used to produce a composite from five popular face-production systems: Sketch, PRO-fit, Electronic Facial Identification Technique (E-FIT), EvoFIT and EFIT-V. An online annex is also made available to provide procedural information for additional composite systems. Practical implications – The work is valuable to forensic practitioners and researchers as a reference for interviewing techniques (involving a CI or an H-CI) and using facial-composite systems. Originality/value – The authors provide an accessible, current guide for how to administer interviewing techniques and how to construct composites from a range of face-production systems