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1.
A new retrieval system for a 3D facial image database was designed and its reliability was experimentally examined. This system has two steps, firstly to automatically adjust the orientation of all 3D facial images in a database to that of the 2D facial image of a target person, and then to identify the facial image of the target person from the adjusted 3D facial images in the database using a graph-matching method. From the experimental study [M. Yoshino, K. Imaizumi, T. Tanijiri, J.G. Clement, Automatic adjustment of facial orientation in 3D face image database, Jpn. J. Sci. Tech. Iden. 8 (2003) 41-47], it is concluded that the software developed for the first step will be applicable to the automatic adjustment of facial orientation in the 3D facial image database. In 28 out of 110 sets (25.5%), the 3D image of the target person was chosen as the best match (from a database of 132 3D facial images) according to the similarity of the facial image characteristics based on the graph matching. The 3D facial image of the target person was ranked in the top of 10 of the database in 75 out of 110 sets (68.2%). These results suggest that this system is inadequate for the identification level, but may be feasible for screening method in a small database. It will be necessary to further pursue the possibility of realization of a facial image retrieval system for a large database such as suspects' facial images in future.  相似文献   

2.
Justice systems around the world are increasingly turning to videoconferencing as a means to reduce delays and reduce costs in legal processes. This preliminary research examined whether interviewing a witness remotely – without physical co-presence of the witness and interviewer – could facilitate the production of quality facial composite sketches of suspects. In Study 1, 42 adults briefly viewed a photograph of a face. The next day they participated in Cognitive Interviews with a forensic artist, conducted either face-to-face or remotely via videoconference. In Study 2, 20 adults participated in videoconferenced interviews, and we manipulated the method by which they viewed the developing sketch. In both studies, independent groups of volunteers rated the likeness of the composites to the original photographs. The data suggest that remote interviews elicited effective composites; however, in Study 1 these composites were considered poorer matches to the photographs than were those produced in face-to-face interviews. The differences were small, but significant. Participants perceived several disadvantages to remote interviewing, but also several advantages including less pressure and better concentration. The results of Study 2 suggested that different sketch presentation methods offered different benefits. We propose that remote interviewing could be a useful tool for investigators in certain circumstances.  相似文献   

3.
Abstract

Facial composite images are often used in the criminal investigation process to facilitate the search for and identification of someone who has committed a crime. Since the use of facial composite images is sometimes relied upon as an integral part of an investigation, it is important to ascertain information about the various decisions made and procedures implemented by law enforcement regarding the use of composites. A 39-item survey was developed to examine the prevalence of a number of procedures related to composite production, including the systems implemented, criteria for selecting systems, law enforcement training, satisfaction with systems, legal challenges, and procedural issues with respect to interviewing multiple witnesses and the distribution of composite images. Surveys were distributed to 1637 city, state and county law enforcement agencies nationwide; 163 completed surveys were returned. This paper summarizes our survey results and discusses the implications for investigative procedures, law enforcement training, and future research needs.  相似文献   

4.
Available facial tissue thickness standards for facial feature reconstruction are based on adult measurements. Mid-facial tissue thicknesses for male and female white adolescents are presented here. Measurements were taken from lateral radiographs produced in an orthodontic practice. Statistical analysis indicates that age, sex, and to some extent, dental occlusion pattern are factors that should be taken into account when attempting facial feature reconstructions.  相似文献   

5.
《Digital Investigation》2014,11(1):67-77
The detection of stego images, used as a carrier for secret messages for nefarious activities, forms the basis for Blind Image Steganalysis. The main issue in Blind Steganalysis is the non-availability of knowledge about the Steganographic technique applied to the image. Feature extraction approaches best suited for Blind Steganalysis, either dealt with only a few features or single domain of an image. Moreover, these approaches lead to low detection percentage. The main objective of this paper is to improve the detection percentage. In this paper, the focus is on Blind Steganalysis of JPEG images through the process of dilation that includes splitting of given image into RGB components followed by transformation of each component into three domains, viz., frequency, spatial, and wavelet. Extracted features from each domain are given to the Support Vector Machine (SVM) classifier that classified the image as steg or clean. The proposed process of dilation was tested by experiments with varying embedded text sizes and varying number of extracted features on the trained SVM classifier. Overall Success Rate (OSR) was chosen as the performance metric of the proposed solution and is found to be effective, compared with existing solutions, in detecting higher percentage of steg images.  相似文献   

6.
7.
Since 1982, the remains of 41 victims of the Green River Serial Murderer have been recovered. The majority were discovered as skeletal remains, and 24 facial approximations have been used in attempts to develop leads for identification of nine of these victims. Nine different artists were used. Interpretations of the same victim varied greatly. For those victims subsequently identified, resemblance of the facial approximation to the deceased showed considerable variation, but in some cases was quite accurate. This experience created a unique opportunity to compare different methods of facial approximation techniques and artists, and to comment on their efficacy in aiding identification.  相似文献   

8.
The purpose of this study was to determine the precision and accuracy of facial soft tissue measurement using personal computer (PC)-based multiplanar reconstructed (MPR) computed tomography (CT) images and to evaluate the effect of the various CT scanning protocols on the facial soft tissue thickness measurement. Thirteen different CT imaging protocols were used to image a cadaver head. MPR reformations and three-dimensional (3D) reconstructions viewed on a laptop PC were used to make measurements at six specific sites on each set of images. These measurements were compared to physical measurements at the same sites. Increasing the slice thickness resulted in decreased image quality. Within the same slice thickness, increasing the pitch ratio in the spiral mode, resulted in decreasing image quality. The image quality of conventional CT scanning was relatively poorer than that of the spiral CT scanning. However, the mean deviation from the physical measurement was within 0.43 mm in every instance. This mean deviation was quite small and clinically acceptable for measuring the soft tissue thickness of the facial area. PC-based MPR CT images of the face using routine scanning CT protocols can be used to accurately measure soft tissue thickness in the facial region. However, for more fine and accurate data collection, scanning protocols with slice thicknesses less than 5mm, and a spiral/helical mode pitch less than 2:1 are recommended.  相似文献   

9.
Facial reconstruction has until now been carried out by the sculpting technique. This method involves building a face with clay or other suitable material on to a skull or its cast, taking into account appropriate facial thickness measurements together with information provided by anthropologists such as approximate age, sex, race and other individual idiosyncrasies. A method for facial reconstruction is presented using 3-D computer graphics and is compared with the manual technique. The computer method involves initially digitising a skull using a laser scanner and video camera interfaced to a computer. A face, from a data bank which has previously digitised facial surfaces, is then placed over the skull in the form of a mask and the skin thickness is altered to conform with the underlying skull. The advantage of the computer method is its speed and flexibility. We have shown that the computer method for reconstructing a face is feasible and furthermore has the advantage over the manual technique of speed and flexibility. Nevertheless, the technique is far from perfect. Further facial thickness data needs collecting and the method requires evaluation using both known control skulls and later unknown remains.  相似文献   

10.
An abundunce of surveillance cameras highlights the necessity of identifying individuals recorded. Images captured are often unintelligible and are unable to provide irrefutable identifications by sight, and therefore a more systematic method for identification is required to address this problem. An existing database of video and photograhic images was examined, which had previously been used in a psychological research project; material consisted of 80 video (Sample 1) and 119 photograhic (Sample 2) images, though taken with different cameras. A set of 38 anthropometric landmarks were placed by hand capturing 59 ratios of inter-landmark distances to conduct within sample and between sample comparisons using normalised correlation calculations; mean absolute value between ratios, Euclidean distance and Cosine θ distance between ratios. The statistics of the two samples were examined to determine which calculation best ascertained if there were any detectable correlation differences between faces that fall under the same conditions. A comparison of each face in Sample 1 was then compared against the database of faces in Sample 2. We present pilot results showing that the Cosine θ distance equation using Z-normalised values achieved the largest separation between True Positive and True Negative faces. Having applied the Cosine θ distance equation we were then able to determine that if a match value returned is greater than 0.7, it is likely that the best match will be a True Positive allowing a decrease of database images to be verified by a human. However, a much larger sample of images requires to be tested to verify these outcomes.  相似文献   

11.
Should adolescents be held as culpable for their behavior as adults? Adolescence is a tumultuous time, full of change and transformation. This paper examines the development of brain functions and cognitive capabilities of teenagers. It explores the effect of alcohol use on brain development and the fundamental cognitive differences between adolescents and adults. This knowledge, coupled with the assessment of developmental perspective, suggests that the adultification of youth (or waiver to adult court) is unduly harsh for youth whose brains have not fully formed.  相似文献   

12.
在2002年底召开的全国司法厅(局)长会议上,司法部党组首次系统提出推进监狱工作法制化、科学化、社会化(以下简称“三化”)建设的要求,这是提高改造质量、提升监狱工作整体水平的重大举措,标志着监狱工作由封闭转向开放、由神秘转向透明、由狭义改造走向广义改造。2003年11月23、24日,司法部在北京召开全国监狱工作“三化”建设座谈会,科学总结了全国监狱一年多“三化”建设工作的实践经验,认真分析了全国监狱“三化”建设工作存在的问题,全面部署下一阶段“三化”建设工作。会议对进一步统一思想,明确目标,全面推进监狱工作“三化”建设进程,实现监狱工作在新时期的新发展和新突破,具有深远的历史意义和重要的现实意义。  相似文献   

13.
The successful identification of a forensic facial reconstruction relies upon many factors other than merely the accuracy of the reconstruction. The way in which the reconstructed head is presented can affect the perception of it, which in turn can affect the recognition rates leading to case resolution. A synthesis of relevant facial perception studies from the psychological literature is provided, followed by a short set of recommendations aimed at practitioners wishing to incorporate the best practice based on current science when presenting their work to the public. These recommendations include pose, background, lighting, and colouring/finishing.  相似文献   

14.
Injuries observed in the facial skull area (FSA) in trauma made by hard blunt objects are registered within the forensic medical examinations of cadavers by far more rare than they are actually encountered in life. At the same time, a statement made to the effect that it was FSA that was affected in injuries of the cerebral skull area (CSA) is of an important forensic medical value. According to our research, the "strength beams" present in FSA and CSA are ovals and semi-ovals positioned above one another in 3 layers (top, medium and low ones). The anterior sections of all layers of FSA "strength beams" and of adjoining CSA regions, i.e. the squama of frontal bone (low one third of it) as well as anterior and middle cranial fossas, are a single deformative strength system. Specific features of each impact-zone region affect greatly a character of injuries in FSA at traumas in the medium facial third. Bones in the anterior and middle cranial fossas are damaged, apart from cranial injuries, in certain variations of impacts to FSA.  相似文献   

15.
作为认知科学的一个新取向,具身认知科学对传统认知科学有很大的突破。其中在元理论上,突破第一代认知科学作为思想基础的身心二元论,取而代之的是身心一体论和身心辨证统一论;突破人是机器的基本论断,提出人是人,与动物和机器不同,具有机器和动物所不具有的意向性和具身性,能够提问,能够沉思他们存在的意义,能够批判地反省其生命的意义,以使其行为方式发生变革;突破语言学哲学尤其是其重要理论形态逻辑实证主义,以心智哲学为指导思想。正是元理论突破,使得具身认知科学建构了与传统认知科学不同的体系,在理论、方法论、研究领域和研究方法等诸多方面都有新的突破。  相似文献   

16.
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18.
利用放射影像资料进行法医临床学鉴定案例越来越多。同一认定常使用的标志包括牙齿、头颅、脊柱等相关特征结构。头颅放射影像资料,包括X片及CT片中的额窦、乳突、蝶鞍、颅缝及其他结构均可作为同一认定的标志。目前,我国法医放射学尚属起步阶段,应加强此方面的研究。  相似文献   

19.
Photoanthropometry is a metric based facial image comparison technique. Measurements of the face are taken from an image using predetermined facial landmarks. Measurements are then converted to proportionality indices (PIs) and compared to PIs from another facial image. Photoanthropometry has been presented as a facial image comparison technique in UK courts for over 15 years. It is generally accepted that extrinsic factors (e.g. orientation of the head, camera angle and distance from the camera) can cause discrepancies in anthropometric measurements of the face from photographs. However there has been limited empirical research into quantifying the influence of such variables. The aim of this study was to determine the reliability of photoanthropometric measurements between different images of the same individual taken with different angulations of the camera. The study examined the facial measurements of 25 individuals from high resolution photographs, taken at different horizontal and vertical camera angles in a controlled environment. Results show that the degree of variability in facial measurements of the same individual due to variations in camera angle can be as great as the variability of facial measurements between different individuals. Results suggest that photoanthropometric facial comparison, as it is currently practiced, is unsuitable for elimination purposes. Preliminary investigations into the effects of distance from camera and image resolution in poor quality images suggest that such images are not an accurate representation of an individuals face, however further work is required.  相似文献   

20.
This study assessed the speed of recognition of facial emotional expressions (happy and angry) as a function of violent media consumption. Color photos of calm facial expressions morphed to either an angry or a happy facial expression. Participants were asked to make a speeded identification of the emotion (happiness or anger) during the morph. Results indicated that, independent of trait aggressiveness, participants high in violent media consumption responded slower to depictions of happiness and faster to depictions of anger than participants low in violent media consumption. Implications of these findings are discussed with respect to current models of aggressive behavior.  相似文献   

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