Full-face View Research Articles

Smile esthetics from the layperson’s perspective

Computer-based smile esthetic surveys based on slider technology allow more precise control of variables and the possibility of obtaining continuous data. Variations in the perception of smiles from different facial perspectives have not been resolved. The objective of this study was to quantify the ideal and the range of acceptable values for smile variables judged by laypersons from a full-face perspective for comparison with lower-face data. Mirrored and symmetric male and female full faces previously determined by peers to be of average attractiveness were used. Ninety-six laypersons judged these smile variables: smile arc, buccal corridor fill, maxillary gingival display, maxillary midline to face, maxillary to mandibular midline discrepancy, overbite, central incisor gingival margin discrepancy, maxillary anterior gingival height discrepancy, incisal edge discrepancy, and cant. The judges manipulated the variables using adjustable image technology that allowed the variable to morph and appear continuous on a computer monitor. Medians for each smile variable were compiled, and the Fleiss-Cohen weighted kappa statistic was calculated to measure reliability. Multiple randomization tests with adjusted P values were used to compare these data with those for lower-face views. Reliability ranged from 0.25 for ideal overbite to 0.60 for upper midline to face, except for upper and lower buccal corridor limits, which each had a kappa value near 0. There were no statistically significant differences between the ratings of male and female raters. The following variables showed statistically and clinically significant differences (>1 mm) when compared with the lower-face view: ideal smile arc, ideal buccal corridor, maximum gingival display, upper to lower midline, and occlusal cant. Although the smile arc values differed because of model lip curvature variations, the principle of tracking the curve of the lower lip was confirmed. For the full-face view, the raters preferred less maximum gingival display, less buccal corridor, more upper to lower midline discrepancy, and less cant of the occlusal plane. Reliability was fair to moderate with the exception of the buccal corridor limits. Most variables showed no clinically meaningful differences from the lower-face view. The acceptable range was quite large for most variables. Detailed knowledge of the ideal values of the various variables is important and can be incorporated into orthodontic treatment to produce an optimal esthetic smile.

Are faces easier to recognize in 3/4 view than in full-face or profile view?

Are faces easier to recognize in 3/4 view than in full-face or profile view?

The Glasgow Face Matching Test

We describe a new test for unfamiliar face matching, the Glasgow Face Matching Test (GFMT). Viewers are shown pairs of faces, photographed in full-face view but with different cameras, and are asked to make same/different judgments. The full version of the test comprises 168 face pairs, and we also describe a shortened version with 40 pairs. We provide normative data for these tests derived from large subject samples. We also describe associations between the GFMT and other tests of matching and memory. The new test correlates moderately with face memory but more strongly with object matching, a result that is consistent with previous research highlighting a link between object and face matching, specific to unfamiliar faces. The test is available free for scientific use.

In-vehicle camera traffic sign detection and recognition

In this paper, we discuss theoretical foundations and a practical realization of a real-time traffic sign detection, tracking and recognition system operating on board of a vehicle. In the proposed framework, a generic detector refinement procedure based on mean shift clustering is introduced. This technique is shown to improve the detection accuracy and reduce the number of false positives for a broad class of object detectors for which a soft response’s confidence can be sensibly estimated. The track of an already established candidate is maintained over time using an instance-specific tracking function that encodes the relationship between a unique feature representation of the target object and the affine distortions it is subject to. We show that this function can be learned on-the-fly via regression from random transformations applied to the image of the object in known pose. Secondly, we demonstrate its capability of reconstructing the full-face view of a sign from substantial view angles. In the recognition stage, a concept of class similarity measure learned from image pairs is discussed and its realization using SimBoost, a novel version of AdaBoost algorithm, is analyzed. Suitability of the proposed method for solving multi-class traffic sign classification problems is shown experimentally for different feature representations of an image. Overall performance of our system is evaluated based on a prototype C++ implementation. Illustrative output generated by this demo application is provided as a supplementary material attached to this paper.

Videotaped interrogations and confessions: does a dual‐camera approach yield unbiased and accurate evaluations?

Although an equal-focus camera perspective-suspect and interrogator each displayed in profile-produces relatively unbiased assessments of videotaped interrogations-confessions, many in law enforcement may consider it less than satisfactory because a full-face view of the suspect is precluded and thus potentially important information revealed in his or her expressions may be unavailable for fact finders' consideration. The present research investigated whether a dual-camera approach, wherein the full faces of both the suspect and interrogator are presented in a split-screen format simultaneously, is a viable alternative to an equal-focus format. Experiment 1 in fact demonstrated that the dual-camera approach does produce relatively unbiased assessments of voluntariness and guilt. However, Experiment 2 revealed that the dual-camera approach was one of the poorest presentation formats in terms of its impact on the ability to accurately distinguish between true and false confessions. Policy recommendations based on the present and previous research are presented.

Sulawesi Onthophagus with paraocular protrusions: ten new species, with a key (Coleoptera: Scarabaeidae: Scarabaeinae)

The Scarabaeinae of the Indonesian island of Sulawesi have always been marginally treated, the only two directly relevant synopses being Boucomont (1914) and Balthasar (1963a, b), the latter author leaning heavily on his French predecessor as far as Sulawesi taxa are concerned. This applies also to the major ingredient of the subfamily, the subcosmopolitan genus Onthophagus Latreille, 1802. Splitting up this megagenus (ca 2000 named species, depending on one’s opinion on subgenera, see below) into smaller, regionally limited operational units – only few wellfounded subgeneric names being available – has been common practice to make its complex taxonomic diversity more manageable. Recently we published the first of a series of reviews on Sulawesi Onthophagus groups (Krikken & Huijbregts 2008). In the present review we treat the Sulawesi species having – in both sexes – a pair of unconnected, upright paraocular protrusions, and unite them in what is here called the Onthophagus lindu group. In this group ten species are recognized, all new, which are keyed, described, and illustrated below. Seven species with paraocular protrusions from Sulawesi are not included in the O. lindu group since one or more of the following attributes, absent from the O. lindu group, justify a position in other known groups: (1) paraocular protrusions connected by a distinct ridge or lamina; (2) ridge delimiting pygidium from propygidium absent; (3) base of the first elytral interstria with swelling; (4) eye foramina (in full-face view) very broad, Sulawesi Onthophagus with paraocular protrusions: ten new species, with a key (Coleoptera: Scarabaeidae: Scarabaeinae)

Motion as a cue for viewpoint invariance

Natural face and head movements were mapped onto a computer rendered three-dimensional average of 100 laser-scanned heads in order to isolate movement information from spatial cues and nonrigid movements from rigid head movements (Hill & Johnston, 2001). Experiment 1 investigated whether subjects could recognize, from a rotated view, facial motion that had previously been presented at a full-face view using a delayed match to sample experimental paradigm. Experiment 2 compared recognition for views that were either between or outside initially presented views. Experiment 3 compared discrimination at full face, three-quarters, and profile after learning at each of these views. A significant face inversion effect in Experiments 1 and 2 indicated subjects were using face-based information rather than more general motion or temporal cues for optimal performance. In each experiment recognition performance only ever declined with a change in viewpoint between sample and test views when rigid motion was present. Nonrigid, face-based motion appears to be encoded in a viewpoint invariant, object-centred manner, whereas rigid head movement is encoded in a more view specific manner.

Why are average faces attractive? The effect of view and averageness on the attractiveness of female faces.

Images of faces manipulated to make their shapes closer to the average are perceived as more attractive. The influences of symmetry and averageness are often confounded in studies based on full-face views of faces. Two experiments are reported that compared the effect of manipulating the averageness of female faces in profile and full-face views. Use of a profile view allows a face to be "morphed" toward an average shape without creating an image that becomes more symmetrical. Faces morphed toward the average were perceived as more attractive in both views, but the effect was significantly stronger for full-face views. Both full-face and profile views morphed away from the average shape were perceived as less attractive. It is concluded that the effect of averageness is independent of any effect of symmetry on the perceived attractiveness of female faces.

Familiarity breeds attraction: effects of exposure on the attractiveness of typical and distinctive faces.

Several studies have shown that facial attractiveness is positively correlated with both familiarity and typicality. Here we manipulated the familiarity of typical and distinctive faces to measure the effect on attractiveness. In our first experiment, we collected ratings of attractiveness, distinctiveness, and familiarity using three different groups of participants. Our stimuli included 84 images of female faces, presented in a full-face view. We replicated the finding that attractiveness ratings negatively correlate with distinctiveness ratings. In addition, we showed that attractiveness ratings were positively correlated with familiarity ratings. In our second experiment, we demonstrated that increasing exposure to faces increases their attractiveness, although there was no differential effect of exposure on typical and distinctive faces. Our results suggest that episodic familiarity affects attractiveness ratings independently of general or structural familiarity. The implications of our findings for the 'face-space' model are discussed.

Face recognition under varying poses: The role of texture and shape

Although remarkably robust, face recognition is not perfectly invariant to pose and viewpoint changes. It has long been known that both profile and full-face views result in poorer recognition performance than a 3/4 view. However, little data exist which investigate this phenomenon in detail. The present work provides such data using a high angular resolution and a large range of poses. Since there are inconsistencies in the literature concerning these issues, we emphasize the different roles of the learning view and the testing view in the recognition experiment. We also emphasize the roles of information contained in the texture and in the shape of a face. Our stimuli were generated from laser-scanned head models and contained either the natural texture or only Lambertian shading and no texture. The results of our same/different face recognition experiments are: (1) only the learning view but not the testing view affects recognition performance. (2) For textured faces the optimal learning view is closer to the full-face view than for the shaded faces. (3) For shaded faces, we find a significantly better recognition performance for the symmetric view. The results can be interpreted in terms of different strategies to recover invariants from texture and from shading.

Incidence of the half-left profile pose in single-subject portraits.

The present work recorded frequencies of five poses (left profile, half-left profile, full-face view, half-right profile, and right profile) by examining 4,180 single-subject portraits of various media. Statistically significant differences were found between the incidence of half-left and half-right profiles. These differences found across media, authorship, and five centuries of portrait work are consistent with right-hemisphere activation models in attentional bias and perception of emotion.

Face recognition in preschool children: effects of familiarity, facial expression and angle of view

The purpose of this study was to investigate the face recognition processes in preschool children. Two experiments were carried out to examine the effects, on face recognition, of familiarity, facial expression and angle of view of faces as well as changes or no changes in facial expression and/or angle of view occurring between the first presentation and the subsequent recognition test. The subjects were 188 five- and six-year old children. In Experiments 1 and 2, half of the faces were highly familiar to the subjects, and the remaining half unfamiliar to them. In Experiment 1, the facial expressions (e.g., smiling or serious) were either changed or unchanged. In Experiment 2, the facial expressions or angles of view (e.g., full-face views or three-quarter views of faces) were either changed or unchanged. The major findings were that the familiar faces and the smiling faces were recognized more correctly than the unfamiliar faces and the serious faces respectively. The results were discussed in terms of 'identity-specific semantic codes' and 'visually-derived semantic codes'.

Preferential Inspection of Views of 3-D Model Heads

The importance of different perspective views for the recognition of model heads was studied. In experiment 1 subjects were instructed to learn the appearance of six heads placed individually on a turntable free to rotate through 360 degrees. Subjects did not distribute their time evenly but focussed their inspection on particular views (the full face view and a view close to the profile). Despite differential inspection of these two views during the learning phase, the face, half profile, and profile views were recognized with equal efficiency in a subsequent recognition task with static views. Experiment 2 used the inspection paradigm to investigate view preference during the recognition of heads from memory. In this experiment subjects were asked to learn the appearance of three heads each seen rotating at an even speed. In a subsequent retrieval task the subjects actively inspected six model heads on the turntable and were asked to differentiate the three heads previously seen rotating from three novel heads. The pattern of inspection in this retrieval task was equivalent to that in experiment 1. Results suggest that during the encoding into memory subjects construct descriptions of specific prototypical views of the head and that descriptions of these same views are preferentially utilised during recognition.

Letters to the Editor

AbstractThe full-face and profile photographic transparencies of 60 subjects (30 male, 30 female) divided equally among Angles Class I. Class II Division I, and Class III malocclusions, taken before and after orthodontic treatment, were randomly distributed in projector carousels and shown to four panels consisting of orthodontists, dental students, art students, and the parents of children undergoing orthodontic treatment. The faces were rated according to the method of Lundstrom et al. (1987). Full-face views generally were rated more attractive than profile views and Class II and Class III malocclusion subjects were rated lower than Class I malocclusion subjects. While the art student and parent panels were less critical in their appraisal of facial attractiveness, they were less sensitive to the changes brought about by orthodontic treatment than the orthodontist and dental student panels, although all could appreciate an improvement in the Class II Division I group.

Panel Perception of Facial Attractiveness

The full-face and profile photographic transparencies of 60 subjects (30 male, 30 female) divided equally among Angles Class I, Class II Division 1, and Class III malocclusions, taken before and after orthodontic treatment, were randomly distributed in projector carousels and shown to four panels consisting of orthodontists, dental students, art students, and the parents of children undergoing orthodontic treatment. The faces were rated according to the method of Lundstrom et al. (1987). Full-face views generally were rated more attractive than profile views and Class II and Class III malocclusion subjects were rated lower than Class I malocclusion subjects. While the art student and parent panels were less critical in their appraisal of facial attractiveness, they were less sensitive to the changes brought about by orthodontic treatment than the orthodontist and dental student panels, although all could appreciate an improvement in the Class II Division 1 group.

Description of a new ecuadorean gnamptogenys species (hymenoptera: formicidae), with a discussion on the status of the alfaria group

Description of a new ecuadorean gnamptogenys species (hymenoptera: formicidae), with a discussion on the status of the alfaria group

Decoding of profile versus full-face expressions of affect

Spontaneous facial expressions were elicited from 64 young adults who watched video segments intended to evoke either positive or negative affect. Subjects viewed the stimuli under conditions where they were alone and thought they were not under visual surveillance. Expressive responses to the emotionally evocative materials were video-taped simultaneously from three perspectives (full-face, a 90° right profile, and a 90° left profile). A subset of facial expressions from 14 males and 14 females was selected and shown to 24 male and 24 female decoders. Judges viewed the expressions in one of the three facial perspectives (full-face, right hemiface, or left hemiface) in either normal or mirror-reversed orientation. Judgments were made for intensity and affective quality of the expressions. Positive expressions were more accurately identified in full-face and in right hemiface views as compared to left hemiface views, while the left hemiface was associated with better accuracy than the right hemiface for negative expressions. Right-looking profiles were associated with higher intensity ratings for both positive and negative affect. Among right-looking profiles, right hemiface expressions were seen as more intense than left hemiface expressions for positive affect. This was also true for full-face views. Full-face views were perceived as more intense for positive affect when the right hemiface was presented to the perceiver's right. This was true for negative expressions when the left hemiface was in the same position.

A biometric comparison of face shape with denture tooth form.

Dentist and patient preferences are often used to select replacement teeth in prosthodontics. Face shape compared with inverted tooth form classifications based on Leon William's work are currently used. Shapes of teeth and faces have been referred to as square, ovoid or tapered, or some combination of these. Six patients, three male and three female, were selected as being classically square, tapered or ovoid in facial form. Three sets of dentures had been made for each patient with tapering, ovoid and square denture teeth. Using a standardized photographic technique, full face views with profiles and close-ups of the teeth were taken. Then from standardized enlarged tracings, key anatomic and derived points were marked, digitized and computer analysed. The face shapes and inverted tooth forms were digitized in the same manner. A comparison of tooth moulds versus the actual denture teeth shows a highly significant difference (P less than 0.001) between set and unset denture teeth. There is also a significant difference (P less than 0.001) between facial form and denture teeth using temporal zygomatic and gonial widths for faces, compared with incisal, contact, and cervical widths for the teeth.

The bridge of the nose: a tutorial dissertation

The aspect allocated to me under this title concerns itself with the height of the nose in profile and also the width of the nasal skeleton which is so noticeable an element in the full-face view. It is worth emphasising in any tutorial that these two are interconnected and that, save in the rarest and well-thought-out instances, one should never reduce the height of a bridge line without also mobilising and narrowing the nasal bones in order to achieve a balanced result.

A critical appraisal of the Abbe flap in secondary cleft lip deformity

Summary A second look has been taken at the Abbe flap as used in 50 patients with postcleft-lip deformities. In reviewing operative revisions following Abbe flap placement in these instances, it is obvious that full-face view improvement is more difficult than that of profile view. The most common problems with the use of the flap were : notching at the flap-lip junctures, redundant vermilion, upper and lower lip scars and an overlong flap. A majority of the problems have been associated with asymmetrical lateral placement which draws attention to the most minor irregularity. Many difficulties would be eliminated if all flaps could be placed centrally. This however is not always feasible, and certainly, many laterally placed flaps have been satisfactory. The techniques of revision have been presented and suggestions made for improving the primary procedures.