The Police Composite Sketch

Facial sketches are widely used by law enforcement agencies to assist in the identification and apprehension of suspects involved in criminal activities. Sketches used in forensic investigations are either drawn by forensic artists (forensic sketches) or created with computer software (composite sketches) following the verbal description provided by an eyewitness or the victim. These sketches are posted in public places and in media in hopes that some viewers will provide tips about the identity of the suspect. This method of identifying suspects is slow and tedious and may not lead to apprehension of the suspect. Hence, there is a need for a method that can automatically and quickly match facial sketches to large police mugshot databases. We address the problem of automatic facial sketch to mugshot matching and, for the first time, compare the effectiveness of forensic sketches and composite sketches. The contributions of this paper include: (i) a database containing mugshots and corresponding forensic and composite sketches that will be made available to interested researchers; (ii) a comparison of holistic facial representations versus component based representations for sketch to mugshot matching; and (iii) an analysis of the effect of filtering a mugshot gallery using three sources of demographic information (age, gender and race/ethnicity). Our experimental results show that composite sketches are matched with higher accuracy than forensic sketches to the corresponding mugshots. Both of the face representations studied here yield higher sketch to photo matching accuracy compared to a commercial face matcher.

Facial Sketches are most widely used in law enforcement agencies for identification and apprehension of suspect which may involve in several criminal activities. If the photographs of the suspect is store in the mug shot data base then the identity of the suspect is possible but in most of the cases that it is a possibility that the photographs of the suspect is not available in the mug shot then two methods are used first is forensic sketch and second is composite sketch software. The sketch used in investigations are either drawn by expert artist (forensic sketch) or created with the help of computer software (composite software sketches), the forensic sketch is drawn by expert artist by following the verbal description provided by an eyewitness. Previous research on sketch recognition in which the (LAP) i.e lightning aware preprocessing method, for face recognition was used as a preprocessing method. Another method was based on extended (ASM) i.e Active shape model for locating a facial feature and previous work for matching sketches to mug shot database was based on (LFDA) i.e local feature based discriminant analysis method was used. And also using PCA algorithm for matching hand drawn face sketch in forensic application. After that the (EUCLBP) i.e enhanced uniform circular local binary pattern for matching sketch in forensic application. But the above process are very slow for identifying the suspect so, for this purpose we propose a (CBR) i.e component based representation approach that is used for matching composite sketches to face photo and with the help of this method we can successfully recognize the face based on sketch.

In law enforcement, face sketch recognition has been used to identify the criminal suspect. Usually, when there is no other evidence, a forensic artist will draw the face of the suspect based on the eyewitness description. Then, the forensic sketch will be matched with the mugshot images from the database in order to recognize and identify the potential suspect. However, the matching performance of the forensic sketches could be affected by various factors, and one of the major factors is the occlusion that exists in the sketch itself. This is because most of the suspects usually wear something that could help in hiding their identities, like a face mask, glasses, hoodie, or cap, when they are committing a crime. Since the mugshot images do not include the occlusion, it will make it harder to recognize the suspect in the matching process, even if the sketch and photo are from the same person. This is due to the larger Euclidean distance between the extracted features from these two images, particularly in the occlusion regions. Therefore, this study proposed a method that matches only the pre-selected regions that exclude occlusion in both images. This region of interest is pre-selected on the forensic face sketch before the same region is applied to all mugshot images. In this study, the forensic sketch with their corresponding photo was obtained from the PRIP-HDC dataset, and the Histogram of Gradient (HOG) was used for feature extraction. Based on the result obtained, this study's performance shows some improvement in recognizing the forensic sketches compared to the existing technique.

Facial composite research has generally focused on the investigative utility of composites-using composites to find suspects. However, almost no work has examined the diagnostic utility of facial composites-the extent to which composites can be used as evidence against a suspect. For example, detectives and jurors may use the perceived similarity of a suspect to a composite as evidence to determine the likelihood of a suspect's guilt. However, research in social cognition and models of cognitive coherence suggest that these similarity judgments may be biased by evaluators' preexisting beliefs of guilt. Two studies examined how preexisting beliefs of guilt influence similarity ratings between a suspect and a facial composite. Study 1 (n = 93) demonstrated that mock-investigators' beliefs in a suspect's guilt inflated their subsequent similarity ratings. Study 2 (n = 49) demonstrated that mock-jurors' beliefs in a defendant's guilt predicted their similarity ratings. These findings highlight a problem of using facial composites as evidence against a suspect, and demonstrate the malleability of similarity judgments.

RationaleThe effect of alcohol intoxication on witness memory and performance has been the subject of research for some time, however, whether intoxication affects facial composite construction has not been investigated.ObjectivesIntoxication was predicted to adversely affect facial composite construction.MethodsThirty-two participants were allocated to one of four beverage conditions consisting of factorial combinations of alcohol or placebo at face encoding, and later construction. Participants viewed a video of a target person and constructed a composite of this target the following day. The resulting images were presented as a full face composite, or a part face consisting of either internal or external facial features to a second sample of participants who provided likeness ratings as a measure of facial composite quality.ResultsIntoxication at face encoding had a detrimental impact on the quality of facial composites produced the following day, suggesting that alcohol impaired the encoding of the target faces. The common finding that external compared to internal features are more accurately represented was demonstrated, even following alcohol at encoding. This finding was moderated by alcohol and target face gender such that alcohol at face encoding resulted in reduced likeness of external features for male composite faces only.ConclusionsModerate alcohol intoxication impairs the quality of facial composites, adding to existing literature demonstrating little effect of alcohol on line-up studies. The impact of intoxication on face perception mechanisms, and the apparent narrowing of processing to external face areas such as hair, is discussed in the context of alcohol myopia theory.

Identification and apprehension of criminals by matching facial sketches with photographic faces is one of the major law enforcement applications of the modern world. Majority of the crime occur where there will not be any information available regarding the suspect. In such situation, forensic sketch artist who usually deal with the eyewitness of the crime or victim in order to draw the sketch that resembles criminal face according to the verbal description given by the eyewitness. These sketches are termed as ‘forensic sketches’ and can be matched manually against gallery of criminal mug shot photos. By developing an automatic system for matching these sketches to the criminal database would reduce many person-hours. The paper presents a novel feature based approach which measures the similarity between sketches and mugshot photos. An efficient preprocessing technique is implemented on sketches and photos. Speed Up Robust Features (SURF) and Scale Invariant Feature Transform (SIFT) features are extracted and the resultant features are matched using nearest neighbor algorithm. Experiment are carried out using 40 composite sketches with 220 photos and it is observed that our two approach with image preprocessing given assuring results with good accuracy.

Sixty-two witnesses observed a target person and two days later either verbally described or constructed a facial composite of the target using the Mac-A-Mug Pro facial composite system. The composite production was preceded by either a guided memory or a standard police interview. The resulting composites were of low quality (not at all similar to a photograph of the target) and were of no value in selecting the target from a group of similar-looking people. It was suggested that the Mac-A-Mug Pro system is not useful for realistic witness settings, in which witnesses must construct the composites from memory. Suggestions are provided for modifying facial composite systems to make them more compatible with the psychological processes mediating face recall.

Background Blast-induced traumatic brain injury is the most prevalent injury sustained by combat soldiers at the frontline. The current study aims to investigate the effectiveness of composite polycarbonate-aerogel face shields with different configurations in mitigating blast-induced brain injuries. Method A series of dynamic fluid–structure interaction simulations of a helmeted head subjected to a frontal free field blast was performed, to evaluate the effectiveness of the current conventional polycarbonate face shield and three other composite face shields with different configurations when exposed to a frontal free-field blast. Results The simulation results demonstrated that the sandwiched structured face shields of polycarbonate and aerogel provided superior blast attenuation than a single-layered polycarbonate face shield. The alternate multi-layered transparent materials of high and low densities provided the best attenuation of blast pressure transmission to the head, with the polycarbonate exterior shell casing contributing to the structural integrity of the face shield, while the lower dense aerogel filler providing high acoustic impedance to blast wave transmission. Conclusion This study provides further insights on future development and design of personal protective equipment in mitigating blast-induced injuries to the head.

Evaluation of appearance transfer and persistence in central face transplantation: A computer simulation analysis

Face perception in autism spectrum disorder: Modulation of holistic processing by facial emotion

It is well documented that facial identity is processed in a holistic manner. Chen & Cheung (2021) recently found that happy faces evoked a larger holistic face processing than angry faces in Caucasian context. Here we adopted the complete composite face paradigm to investigate how facial emotion influenced holistic processing of facial identity in Chinese context. In Experiment 1, we used Chinese faces with happy, neutral and surprise emotion. Participants judged whether the top halves of the two successively presented composite faces were same or different, while their facial emotion was always consistent in a trial. We found equal composite face effects (CFE) for the three emotional faces. In Experiment 2, either top halves or bottom halves were judged, and angry, happy, fearful and neutral faces were compared. Results showed that although judging the top half induced a larger CFE than judging the bottom half, the CFE was equal among four emotional faces. In Experiment 3, angry and happy faces with high/low emotional intensity were further compared. We also found equal CFE for angry and happy faces, which was not modulated by the emotional intensity. These results indicated that the holistic processing of facial identity is robust and constant regardless of emotion categories and emotion intensity in Chinese context. The relation between cultural difference and holistic processing of emotional faces should be considered in the future.

Collapse mechanisms of sandwich beams with composite faces and a foam core, loaded in three-point bending. Part II: experimental investigation and numerical modelling

We used the composite-face illusion and Navon stimuli to determine the consequences of priming local or global processing on subsequent face recognition. The composite-face illusion reflects the difficulty of ignoring the task-irrelevant half-face while attending the task-relevant half if the half-faces in the composite are aligned. On each trial, participants first matched two Navon stimuli, attending to either the global or the local level, and then matched the upper halves of two composite faces presented sequentially. Global processing of Navon stimuli increased the sensitivity to incongruence between the upper and the lower halves of the composite face, relative to a baseline in which the composite faces were not primed. Local processing of Navon stimuli did not influence the sensitivity to incongruence. Although incongruence induced a bias toward different responses, this bias was not modulated by priming. We conclude that global processing of Navon stimuli augments holistic processing of the face.Electronic supplementary materialThe online version of this article (doi:10.3758/s13414-011-0109-7) contains supplementary material, which is available to authorized users.

We used the composite-face illusion and Navon stimuli to determine the consequences of priming local or global processing on subsequent face recognition. The composite-face illusion reflects the difficulty of ignoring the task-irrelevant half-face while attending the task-relevant half if the half-faces in the composite are aligned. On each trial, participants first matched two Navon stimuli, attending to either the global or the local level, and then matched the upper halves of two composite faces presented sequentially. Global processing of Navon stimuli increased the sensitivity to incongruence between the upper and the lower halves of the composite face, relative to a baseline in which the composite faces were not primed. Local processing of Navon stimuli did not influence the sensitivity to incongruence. Although incongruence induced a bias toward different responses, this bias was not modulated by priming. We conclude that global processing of Navon stimuli augments holistic processing of the face.

Contemporary scientific literature is controversial about the two basic mechanisms that play a significant role in the identification and discrimination of facial expressions, that is, the analytic process (perceiving individual facial features) and the holistic process (perceiving the face as a Gestalt). Despite the large number of studies, the question of their relative contributions into the perception of facial expressions remains open. In the present study, we investigated the interaction of the analytic and holistic processing simultaneously using the methods of composite and inverted faces in the task of assessing the expression similarity. To achieve this goal, the method of multidimensional scaling was used to enable the construction of a subjective space of expression similarities and then to analyze the clustering of expressions under up-right and inverted exposure conditions. The results showed that: 1. In up-right conditions of face presentations holistic processing plays a more important role; 2. Under the inverted conditions, the role of analytic processing is increased that is manifested in a change of expression clustering in the subjective space of expression similarities; 3. The method of multidimensional scaling is productive for investigating the interaction of analytic and holistic encoding mechanisms of facial expressions; 4. Sharing methods of the composite and inverted faces is an effective tool for changing the impact of analytic and holistic processes in assessing expression similarities.