基于Harris算子和K-means聚类的红外图像脸部特征自动定位

目的 研究一种红外医学图像处理与分析方法,实现红外人脸图像中特征区域的自动定位.方法 针对红外正面脸部图像,采用一种无监督的局部和全局的特征提取方法,首先通过阈值法区分出前景和背景,并根据面部特征对称性在前景中确定鼻区;然后在面部确定一个包含所有特征的矩形区域,利用Harris算子在该区域检测出角点,并找出这些点的局部最大值点;最后用K-means方法对这些点进行聚类.结果 100幅临床图像的实验表明,该方法可实现红外人脸图像中眼、鼻、口的自动定位,并能够准确划分脸部的特征区域.结论 本文所建立的图像分析方法可快速、简捷地实现红外图像面部特征自动定位,且重复性较好、可信度较高.     

A new computer-assisted technique to aid personal identification

The paper describes a procedure aimed at identification from two-dimensional (2D) images (video-surveillance tapes, for example) by comparison with a three-dimensional (3D) facial model of a suspect. The application is intended to provide a tool which can help in analyzing compatibility or incompatibility between a criminal and a suspect’s facial traits. The authors apply the concept of “geometrically compatible images”. The idea is to use a scanner to reconstruct a 3D facial model of a suspect and to compare it to a frame extracted from the video-surveillance sequence which shows the face of the perpetrator. Repositioning and reorientation of the 3D model according to subject’s face framed in the crime scene photo are manually accomplished, after automatic resizing. Repositioning and reorientation are performed in correspondence of anthropometric landmarks, distinctive for that person and detected both on the 2D face and on the 3D model. In this way, the superimposition between the original two-dimensional facial image and the three-dimensional one is obtained and a judgment is formulated by an expert on the basis of the fit between the anatomical facial districts of the two subjects. The procedure reduces the influence of face orientation and may be a useful tool in identification.     

Assessment of some problematic factors in facial image identification using a 2D/3D superimposition technique

The number of criminal cases requiring facial image identification of a suspect has been increasing because a surveillance camera is installed everywhere in the city and furthermore, the intercom with the recording function is installed in the home. In this study, we aimed to analyze the usefulness of a 2D/3D facial image superimposition system for image identification when facial aging, facial expression, and twins are under consideration. As a result, the mean values of the average distances calculated from the 16 anatomical landmarks between the 3D facial images of the 50s groups and the 2D facial images of the 20s, 30s, and 40s groups were 2.6, 2.3, and 2.2 mm, respectively (facial aging). The mean values of the average distances calculated from 12 anatomical landmarks between the 3D normal facial images and four emotional expressions were 4.9 (laughter), 2.9 (anger), 2.9 (sadness), and 3.6 mm (surprised), respectively (facial expressions). The average distance obtained from 11 anatomical landmarks between the same person in twins was 1.1 mm, while the average distance between different person in twins was 2.0 mm (twins). Facial image identification using the 2D/3D facial image superimposition system demonstrated adequate statistical power and identified an individual with high accuracy, suggesting its usefulness. However, computer technology concerning video image processing and superimpose progress, there is a need to keep familiar with the morphology and anatomy as its base.     

The creation of inter-ethnic images for studies in applied psychology

The facial transformation programme, is an integral part of the computerised three-dimensional facial reconstruction system, employed at the University of Glasgow for forensic and historical cases. It was applied to the creation of inter-ethnic images for use in studies to assess the response of various groups to facial appearance in the assessment of racial stereotyping. We initially acquired a three-dimensional facial image from a young black (Negroid) male volunteer, using our optical laser scanning system. This image was then used as a template over a Caucasian skull to produce a reconstruction using facial criteria applicable to white (Caucasian) males. The other image used was that of the facial template of the black male. A commercially available electronic identikit system, E-FIT was then used to add appropriate hair styles and open eyes to both images. In addition, on the 'Caucasian reconstruction' we were able to reduce the contrast and lighting on the face. This was relatively straightforward as we were using greyscale images rather than colour. The shape of the nose and lips on the white male were also altered to be more in keeping with Caucasoid average measurements. The resulting images were shown to a group of second-year clinical psychology students and their responses are discussed. Similar images may also be used in studies of racial stereotyping in different categories of professionals such as police, prison personnel, probation officers, social workers, potential employers, doctors, and others, in order to assess the response to individuals by facial appearance.     

Countermeasures to the problem of accidents to intoxicated pedestrians

A substantial part of the pedestrian accident problem arises from intoxicated pedestrians. Possible countermeasures are reviewed, organised into: (a) prevention of high levels of intoxication in pedestrians, (b) minimising pedestrian activity in the intoxicated, and (c) minimising risk of injury among intoxicated pedestrians. It is concluded that improved safety of intoxicated pedestrians is most likely to come about by making the environment safer for all pedestrians, drunk or sober. The measure that would be expected to have the greatest effect quickest is a reduced speed limit, especially in locations where traffic is busy and there are many pedestrians.     

Gesichtsweichteilrekonstruktion mithilfe einer Open-Source-Software

Background

The identification of an unknown deceased person is an important task in forensic anthropology. There are various methods for identification, such as fingerprinting, odontostomatology and genetic fingerprinting, which presuppose the existence of reference material of the missing person; however, if there is no evidence of a person’s identity the only possibility is often the use of forensic facial soft tissue reconstruction. This method is based on the high recognition level of a human face on the basis of bony structures of the skull and its anatomical features.

Aim

The aim of this study was the design and application of a novel process for a computer-aided 3D facial soft tissue reconstruction on the basis of digital photographs of a skull.

Material and methods

The facial soft tissue reconstruction was carried out on a selected forensic case and based on open source software.

Results

A complete facial soft tissue reconstruction of the deceased person was created based on 76 photographs of the skull taken with a Nikon D7100 SLR digital camera. The results show that for actual comparison images similar reconstruction results can be achieved. In addition, a model library for facial features was created.

Conclusion

The presented workflow of a computer-aided 3D facial soft tissue reconstruction based on open source software is a cost-effective and flexible alternative to conventional reconstruction methods. It could be demonstrated that comparable reconstruction results can be achieved. Whether the reconstruction result actually leads to the recognition of the person depends on many other factors.

     

应用非致冷镜头的红外热成像仪对76例正常人阳虚质的评价研究

目的:探讨非致冷镜头的红外热成像仪扫描下阳虚体质的评价部位。方法:募集22~71岁健康人共80例,根据中医体质调查表筛选出平和体质及阳虚体质的健康人76例纳入本研究,分为健康平和质组(30例)和健康阳虚质组(46例)。运用HIR-2000型红外热像诊断系统,对每位受试者行全身扫描并采集图像,完成每例受试者全身共计47个区位热值的测量,所有数据在SPSS 19.0软件下进行分析。结果:2组受试者年龄分布差异无统计学意义;健康平和质组与健康阳虚质组红外热成像热值表现特点如下:47个区位中,前额和面部为热值最高的2个区位,头后位上部和头后位中部为热值最低的2个区位。健康平和质组较健康阳虚质组在示指、中指、无名指、股前区、膝部、小腿前区、股后区、小腿后区等8个区位热值更高(P0.05);其中,股后区、小腿后区热值偏高更明显(P0.01)。结论:①示指、中指、无名指和下肢是应用非致冷镜头的红外热像诊断系统判定阳虚的敏感区位。②无论何种致冷方式的红外热成像仪对膝部、股后区与小腿后区热值差异的研究具有可重复性。③冬季仅行下肢部扫描即可进行阳虚评价。     

Facial image comparisons of morphed facial imagery

ABSTRACT

Facial image morphing is a technique whereby two or more faces are blended together to create a new face (the morph). Apps and open source software are now freely available to create morphs. While morph creation is predominantly for entertainment value, it is also a method being used to create facial imagery for use on fraudulent identity documents. This study sought to answer two questions. First, would participants accept a morph persona (an identity created using only morphed facial imagery) as a credible identity? Second, could participants match faces that had been used to create a morph (so-called constituent faces)? Results showed that morph personas were credible, being correctly matched more often than alternative images of real people. Further, results showed that propensity to declare a constituent face a match to its morph was dependent on the type of morph, with morphs made using two faces more likely to yield matches than those made using eight or 16 faces. A follow up similarity study on faces selected showed that even if a constituent face was selected it would more than likely have been ruled out as a match following a more thorough one-to-one comparison.     

A blind accuracy assessment of computer-modeled forensic facial reconstruction using computed tomography data from live subjects

A computer modeling system for facial reconstruction has been developed that employs a touch-based application to create anatomically accurate facial models focusing on skeletal detail. This article discusses the advantages and disadvantages of the system and illustrates its accuracy and reliability with a blind study using computed tomography (CT) data of living individuals. Three-dimensional models of the skulls of two white North American adults (one male, one female) were imported into the computer system. Facial reconstructions were produced by two practitioners following the Manchester method. Two posters were produced, each including a face pool of five surface model images and the facial reconstruction. The face pool related to the sex, age, and ethnic group of the target individual and included the surface model image of the target individual. Fifty-two volunteers were asked to choose the face from the face pool that most resembled each reconstruction. Both reconstructions received majority percentage hit rates that were at least 50% greater than any other face in the pool. The combined percentage hit rate was 50% above chance (70%). A quantitative comparison of the facial morphology between the facial reconstructions and the CT scan models of the subjects was carried out using Rapidform^™ 2004 PP2-RF4. The majority of the surfaces of the facial reconstructions showed less than 2.5 mm error and 90% of the male face and 75% of the female face showed less than 5 mm error. Many of the differences between the facial reconstructions and the facial scans were probably the result of positional effects caused during the CT scanning procedure, especially on the female subject who had a fatter face than the male subject. The areas of most facial reconstruction error were at the ears and nasal tip.     

采用远红外热成像技术评估运动效果初步实验研究

目的:采用远红外热成像技术监测运动效果,无损实时考察人体局部温度与运动量之间的关系.方法:设计定量负荷和最大负荷上肢负重力量训练实验,双手持重物同时向前上方举起直至与视线平行,每10次动作为1组,每组实验后采集被试正背面上半身及左右侧面的红外热图数据,结合人体二维解剖学结构图谱进行定性分析,解读运动发力肌群表面温度动态...     

Multidetector and three-dimensional CT evaluation of the patient with maxillofacial injury

Interpretation of images associated with the traumatically injured face is challenging. The complexity of facial anatomy, coupled with the superimposition of numerous bony structures on plain radiographs, poses specific obstacles to accurate interpretation of facial injury. Although plain radiographs can be helpful in cases of isolated injuries, CT is the most useful modality for evaluating facial injury. This article reviews facial anatomy as it pertains to traumatic injury, emphasizes the clinical findings associated with various types of facial injury, and simplifies the diagnosis of facial injury on CT.     

Three-dimensional computed tomographic angiography of pulmonary vessels.

OBJECTIVE: To assess the image quality of multiple threshold display (MTD) as a new technique for generating three-dimensional (3D) pulmonary computed tomographic (CT) angiographic images. METHODS: We used MTD, a type of shaded surface display (SSD) offering the selection of multiple thresholds and transparencies, to reconstruct 3D-CT angiograms from enhanced helical CT data sets in 33 patients with lung disease. In MTD, eight thresholds of CT values are selected, and transparency is assigned to each. The selected voxels, ranging from -600 to 1,000 Hounsfield Units, were divided into eight classes, and transparency ranging from 0 to 100% was assigned to each. The CT scanner employed was a Toshiba Xvigor. MTD and SSD images were generated by using an Xtension with a Sun SPARC station 20, and they were compared by two radiologists. RESULTS: The image quality of MTD images was superior to that of SSD images (p < 0.01), because the MTD images demonstrated clearly both the major and small vessels. CONCLUSION: MTD is a useful technique for 3D pulmonary CT angiography.     

Imaging of the facial nerve

The facial nerve is responsible for the motor innervation of the face. It has a visceral motor function (lacrimal, submandibular, sublingual glands and secretion of the nose); it conveys a great part of the taste fibers, participates to the general sensory of the auricle (skin of the concha) and the wall of the external auditory meatus. The facial mimic, production of tears, nasal flow and salivation all depend on the facial nerve.In order to image the facial nerve it is mandatory to be knowledgeable about its normal anatomy including the course of its efferent and afferent fibers and about relevant technical considerations regarding CT and MR to be able to achieve high-resolution images of the nerve.     

Preliminary study on automated detection of cerebral vessels from head CTA images

We propose an approach for automated detection of cerebral vessels from head CT angiographic images. This approach contains two major features. First, instead of using the well-known image-processing techniques such as thresholding and labeling, a novel Laplacian-like filter is developed and employed in the region of interest in an image to be processed. Second, not only is the axial-view image reconstructed from head CT angiographic images used, but, in addition, the sagittal- and coronal-view images are reconstructed and used. By applying these major features in the process of detection of brain vessels, more accurate results can be achieved. To validate the effectiveness of the proposed method, we applied the method to three clinical cases, all of which were head CT angiograms. Our preliminary results showed that the proposed method has the potential to automatically detect cerebral vessels in head CT angiograms with acceptable accuracy.     

Automated tracking and computer reproduction of vessels in DSA images

We are developing an automated vessel-tracking method based on the double-square-box region-of-search technique, for efficient tracking of the connected vascular tree in a digital subtraction angiography (DSA) image. Tracking points and branch vessels are located by searching of the perimeter of boxes, which are centered on previously determined tracking points. The most accurate results (90% true-positive rate with six false-positives per image) are obtained by tracking using the double-square-box method. In relatively straight regions of vessels, a large box is employed for efficient tracking; in curved regions of vessels, a small box is employed to ensure accurate tracking. When tracking is completed, accurate vessel information, ie, the vessel position, size, and contrast determined at each tracking point, is available for further quantitative analysis. Computer reproductions of tracked vessel trees appear to correspond well to those in DSA images.     

Facial reconstruction using 3-D computerized method: A scoping review of Methods,current Status,and future developments

Facial reconstruction (otherwise known as facial approximation) is an alternative method that has been widely accepted in forensic anthropological and archaeological circumstances. This method is considered useful for creating the virtual face of a person based on skull remain. Three-dimensional (3-D) traditional facial reconstruction (known as sculpture or manual method) has been recognized for more than a century; however, it was declared to be subjective and required anthropological training. Until recently, with the progression of computational technologies, many studies attempted to develop a more appropriate method, so-called the 3-D computerized facial reconstruction. This method also relied on anatomical knowledge of the face-skull relationship, divided into semi- and automated based computational method. The 3-D computerized facial reconstruction makes it more rapid, more flexible, and more realistic to generate multiple representations of faces. Moreover, new tools and technology are continuously generating fascinating and sound research as well as encouraging multidisciplinary collaboration. This has led to a paradigm shift in the 3-D computerized facial reconstruction to a new finding and new technique based on artificial intelligence in academia. Based on the last 10-years scientific-published documents, this article aims to explain the overview of the 3-D computerized facial reconstruction and progression as well as an issue relating to future directions to encourage further improvement.     

Holographic topometry for a dense visualization of soft tissue for facial reconstruction

Facial reconstruction can be used as a forensic technique to identify a person, when no other identification method is applicable. The facial soft tissue thickness applied to the skull is crucial when performing an accurate facial reconstruction. Historically, scientists developed several techniques to measure the soft tissue of the face. It was their aim, to build a database of a unique point-set, differentiated by gender, age, ethnic origin, BMI. All used a limited number of landmarks and an inaccurate measuring technique. We developed a contact-free and precise measuring technique, using low-dose CT and holographic data. Due to the extremely short exposure time, the holographic measurement is very precise. We lay out our first experiences to create a facial soft tissue layer map of the face.     

Individual shedder status and the origin of touch DNA

Due to improved laboratory techniques, touched surfaces and items are increasingly employed as sources of forensic DNA evidence. This has urged a need to better understand the mechanisms of DNA transfer between individuals. Shedder status (i.e. the propensity to leave DNA behind) has been identified as one major factor regulating DNA transfer. It is known that some individuals tend to shed more DNA than others, but the mechanisms behind shedder status are largely unknown. By comparing the amounts of DNA deposited from active hands (i.e. used “as usual”) and inactive hands (i.e. not allowed to touch anything), we show that some of the self-DNA deposited from hands is likely to have accumulated on hands from other parts of the body or previously handled items (active hands: 2.1 ± 2.7 ng, inactive hands: 0.83 ± 1.1 ng, paired t-test: p = 0.014, n = 27 pairs of hands). Further investigation showed that individual levels of deposited DNA are highly associated with the level of DNA accumulation on the skin of the face (Pearson’s correlation: r = 0.90, p < 0.00001 and Spearman’s ranked correlation: r_s = 0.56, p = 0.0016, n = 29). We hypothesized that individual differences in sebum secretion levels could influence the amount of DNA accumulation in facial areas, but no such correlation was seen (Pearson’s correlation: r = − 0.13, p = 0.66, n = 14). Neither was there any correlation between DNA levels on hands or forehead and the time since hand or face wash. We propose that the amount of self-DNA deposited from hands is highly influenced by the individual levels of accumulated facial DNA, and that cells/DNA is often transferred to hands by touching or rubbing one’s face.     

Sectional neuroanatomy of the face

Needle electromyography and the injection procedures of the face are difficult because of the small size and close anatomic relations of the facial structures. Local injections of the face have increased in frequency since the introduction of botulinum toxin. This article intends to provide anatomically accurate schematics of innervation of the muscles of facial expression that can be used to interpret magnetic resonance images of the muscles and nerves. Cross-sectional schematics of the face were drawn as they appear in imaging projections. The relevant cranial and spinal nerves were color coded. The muscles and skin surfaces were labeled and assigned the color of the appropriate nerves. An organized comprehensive map of the motor innervation of the face allows the physician to increase the accuracy and efficacy of interventional procedures. This could also assist the electromyographer in correlating the clinical and electrophysiologic findings with magnetic resonance images.