Body Height Measurements in Images

Abstract:  For any measurement of a person's height in an image, a difference exists between the actual height of the person and the image measurement. In order to gain knowledge about statistical behavior of differences between actual and measured heights it is necessary to make reference recordings, e.g., of test persons under the same recording conditions. To test whether the differences are dependent on camera and further circumstances, an experiment was set up which involved the measurement of 22 test persons using three cameras of varying quality. Reproducibility of measurements per image appears to be strongly dependent on the camera (quality), whereas systematic bias differs with the view point of the camera. Operator dependency of the measurement process is found, so its repetition by different operators is recommended.     

Suspect Height Estimation Using the Faro Focus3D Laser Scanner

At present, very little research has been devoted to investigating the ability of laser scanning technology to accurately measure height from surveillance video. The goal of this study was to test the accuracy of one particular laser scanner to estimate suspect height from video footage. The known heights of 10 individuals were measured using an anthropometer. The individuals were then recorded on video walking along a predetermined path in a simulated crime scene environment both with and without headwear. The difference between the known heights and the estimated heights obtained from the laser scanner software were compared using a one-way t-test. The height estimates obtained from the software were not significantly different from the known heights whether individuals were wearing headwear (p = 0.186) or not (p = 0.707). Thus, laser scanning is one technique that could potentially be used by investigators to determine suspect height from video footage.     

法庭语音学

本文对法庭语音学进行了研究综述,主要介绍了该学科的核心内容：说话人鉴定。在实际办案中,当未找到嫌疑人,只有犯罪分子的检材语音时,可以使用说话人画像/说话人分类技术。若没有犯罪分子的录音证据时,可以让受害人和证人进行说话人的听觉辨认。具体的辨认形式有两种：对熟人辨认和对陌生人辨认,在对陌生人辨认时可以采用语音辨认的方法进行。当检材语音和样本语音都齐备的时候,法庭语音分析专家就可以对二者进行比对检验了。目前语音比对分析涉及到的问题和领域有：基于贝叶斯方法的法庭推理和似然比计算、共振峰频率的测量应用、非解析感知与样例理论、法庭说话人自动识别以及不同方法的综合应用等。     

Sexual Dimorphism of Maxillary Sinus Dimensions Using Cone‐Beam Computed Tomography

Sex determination of unknown persons plays an important role in forensic medicine. Cone‐beam computed tomography (CBCT) is an excellent imaging modality for accurate measurement of maxillary sinus dimensions. This study aimed to evaluate whether maxillary sinus measurements on CBCT scans can be applied for sex determination. The width, length, and height of maxillary sinuses in CBCT images of 100 patients (50 males and 50 females) were measured. Student's t‐test and discriminant function analysis were used to compare differences in the measured parameters between males and females. The correct predictive accuracy rate of sex determination was 78% in females and 74% in males with overall accuracy of 76%. Based on discriminant analysis, the most pronounced variable in differentiation of sex groups was maxillary sinus height. This study suggests that maxillary sinus measurements can be valuable for sex determination in forensic investigation, especially for cases in which other traditional methods are not applicable.     

计算机X线摄片测量四川地区活体男性颈椎推算身高

目的 以计算机放射学(computer radiography,CR)X线摄影方法,摄颈椎侧位CR片,测量颈椎高度,建立推算身高的回归方程.并评估放射学方法测量颈椎高度推算身高的可行性.方法 在150例四川汉族成年活体男性颈椎CR片上测量C3～C7前、后缘高度,同时测量其身高.通过各项颈椎测量指标与身高的线性回归分析,建立颈椎推算身高的回归方程;并对方程进行身高预测值与实际值的配对t检验、残差分析、等方差性检验以及共线性检验等方程的预测与诊断.结果 共建立有统计学意义的一元回归方程31个,多元回归方程20个.所建立回归方程的复相关系数在0.656～0.259范围内,身高估计值标准误在4.30-5.79cm范围.结论 所建立的回归方程适用于四川汉族成年男性颈椎身高推算.应用CR放射学方法测量颈椎高度推算身高,可以为法医学个人识别身高推算提供帮助.     

Determining body height by the femur and femoral fragments

Using a forensic series of human specimens, the reliability of frequently-cited formulas applied to estimate body height on the basis of the femur was examined with regard to their accuracy. Very few proved reliable enough to render accurate results. In most cases, less than half of the actual body heights were found to have predicted within the single estimation interval. The method to be used for such estimations must therefore be selected with great care. Even with partial femur measures, it is possible to estimate reliably body height. In particular, the circumference of the diaphysis centre correlates well with body height. The regression equations calculated in the present study, however, reveal greater errors in estimates than the formulas worked out using the total femur length.     

The application of anthropometric indices in forensic photography: three case studies.

With increasing commercial use of video surveillance to deter crime, physical anthropologists are becoming more involved in the forensic identification of persons based on photographic evidence. Three contrasting case studies from southern Florida are presented that illustrate the utilization of conventional anthropometry in determining the identity of suspects. In each case an arrested suspect and a subject videotaped during the commission of a crime are compared with respect to a series of discrete craniofacial and post-cranial proportions. Each case analysis is supplemented by additional data on earlobe structure, head and facial hair patterns, degree of chin eminence, presence or absence of tattoos, and various aspects of bodily dimensions and physique including height and weight estimations.     

Human height estimation from highly distorted surveillance image

Video surveillance camera (VSC) is an important source of information during investigations especially if used as a tool for the extraction of verified and reliable forensic measurements. In this study, some aspects of human height extraction from VSC video frames are analyzed with the aim of identifying and mitigating error sources that can strongly affect the measurement. More specifically, those introduced by lens distortion are present in wide-field-of-view lens such as VSCs. A weak model, which is not able to properly describe and correct the lens distortion, could introduce systematic errors. This study focuses on the aspect of camera calibration to verify human height extraction by Amped FIVE software, which is adopted by the Forensic science laboratories of Carabinieri Force (RaCIS), Italy. A stable and reliable approach of camera calibration is needed since investigators have to deal with different cameras while inspecting the crime scene. The performance of the software in correcting distorted images is compared with a technique of single view self-calibration. Both approaches were applied to several frames acquired by a fish-eye camera and then measuring the height of five different people. Moreover, two actual cases, both characterized by common low-resolution and distorted images, were also analyzed. The height of four known persons was measured and used as reference value for validation. Results show no significant difference between the two calibration approaches working with fish-eye camera in test field, while evidence of differences was found in the measurement on the actual cases.     

Increasing Allele Detection by Altering the Quantity of Internal Lane Standard

Electrokinetic injection (EI) is the primary method used in forensic laboratories to load amplified PCR product in capillary electrophoresis for short tandem repeat (STR) fragment separation. Because all samples subjected to capillary electrophoresis use internal lane standard (ILS), this study investigated the consequence of varying the volume of ILS and its effects on allele peak heights and number of alleles detected. Results demonstrated that when the volume of ILS is reduced, the average peak height and number of alleles increased, thereby increasing the sensitivity of the detection method. Sizing anomalies were observed; however, they did not adversely affect accuracy and precision. The method developed in this study offers a simple and universal procedure to increase the alleles detected in forensic STR analysis. Reducing the volume of ILS to achieve greater sensitivity is applicable to all STR amplification kits and capillary electrophoresis instruments currently used in forensic DNA analysis.     

Rapid quantification and sex determination of forensic evidence materials

DNA quantification of forensic evidence is very valuable for an optimal use of the available biological material. Moreover, sex determination is of great importance as additional information in criminal investigations as well as in identification of missing persons, no suspect cases, and ancient DNA studies. While routine forensic DNA analysis based on short tandem repeat markers includes a marker for sex determination, analysis of samples containing scarce amounts of DNA is often based on mitochondrial DNA, and sex determination is not performed. In order to allow quantification and simultaneous sex determination on minute amounts of DNA, an assay based on real-time PCR analysis of a marker within the human amelogenin gene has been developed. The sex determination is based on melting curve analysis, while an externally standardized kinetic analysis allows quantification of the nuclear DNA copy number in the sample. This real-time DNA quantification assay has proven to be highly sensitive, enabling quantification of single DNA copies. Although certain limitations were apparent, the system is a rapid, cost-effective, and flexible assay for analysis of forensic casework samples.     

物证鉴定证据应用层级论

用物证鉴定结论证明犯罪需要经过推理过程,将物证来源鉴定结论转化为嫌疑人行为推论,后者再作为法律事实证明嫌疑人是否有罪。物证鉴定证据应用的递进证明关系,可以用由依次推理关系连接的物证来源结论层、行为推论层和定罪层构成的物证鉴定层级模型描述。该模型可直观表达和评估物证鉴定结论证据应用效力。     

Photographic Image Comparison of Vegetation

Images and videos are common types of evidence in crime scene investigations and laboratory analysis. Images may be taken by the suspect and/or by crime scene investigators and may serve as crucial elements in forensic laboratory analysis. Forensic photographic image comparison is the process of comparing one or more objects or persons in photographs/images when at least one image is known to be related to a crime. The forensic examiner usually compares the images in order to determine whether or not an association between the exhibits in the images can be made. This paper proposes an extension to the currently prevalent photographic image examination method. The extension introduces comparison of landscape and vegetation over time. It is revealed that similarities between images may still be found between the period of time the suspect photograph was taken and the period the crime scene investigator took the photograph from the same area. In this case report, two suspects to be involved in growing a marijuana field were arrested by the police. The forensic experts were asked to examine images taken by the crime scene investigators and to compare them to the images found in the suspects’ phones. They then tried to determine whether the suspects could be linked to the specific locations. While applying techniques derived from morphological comparison methodologies, the plants at the scene provided significant additional information. A tree trunk, branches, and twigs on a hedge in the photographs revealed specific individual characteristics that led the examiner to reach a conclusive decision.     

放射影像学方法测量活体女性颈椎推算身高

目的测量颈椎高度建立四川汉族女性人群的身高推算方程，为法医学个人识别提供帮助。方法应用计算机X线摄影放射学方法，在209例四川汉族女性颈椎CR片上测量C3～C7椎体高度，并准确测量身高。按年龄是否大于45岁进行分组，对各颈椎的测量数据与身高进行线性回归分析，建立颈椎推算身高的回归方程。结果共建立一元回归方程36个，多元回归方程12个，所有回归方程经线性回归模型假设检验，均有统计学意义（P〈0．05）。所建立的回归方程的复相关系数（r）在0．628～0．280范围内，回归方程的标准误在4．03～5．03cm范围内。结论本研究所建立的回归方程，可用于四川汉族女性颈椎的身高推算。     

Failure of anthropometry as a facial identification technique using high-quality photographs

Anthropometry can be used in certain circumstances to facilitate comparison of a photograph of a suspect with that of the potential offender from surveillance footage. Experimental research was conducted to determine whether anthropometry has a place in forensic practice in confirming the identity of a suspect from a surveillance video. We examined an existing database of photographic lineups, where one video image was compared against 10 photographs, which has previously been used in psychological research. Target (1) and test (10) photos were of high quality, although taken with a different camera. The anthropometric landmarks of right and left ectocanthions, nasion, and stomion were chosen, and proportions and angle values between these landmarks were measured to compare target with test photos. Results indicate that these measurements failed to accurately identify targets. There was also no indication that any of the landmarks made a better comparison than another. It was concluded that, for these landmarks, this method does not generate the consistent results necessary for use as evidence in a court of law.     

Stature estimation based on dimensions of the bony pelvis and proximal femur

Pelin et al. recently showed that sacral height measured on lateral magnetic resonance images can be used with moderate accuracy to reconstruct stature in males. In most forensic anthropological cases, however, sacral dimensions must be obtained from dry bones. In this study, the relationship between stature and sacral height, hip height, and femur head diameter measured on dry bone was evaluated for American Blacks and Whites of both sexes (n = 247). There are significant correlation between stature and these three dimensions, but the results suggest that none of the dimensions predict stature with the accuracy needed to be useful in forensic anthropological investigations.     

Bayesian framework for the evaluation of fiber evidence in a double murder--a case report

Fiber evidence found on a suspect vehicle was the only useful trace to reconstruct the dynamics of the transportation of two corpses. Optical microscopy, UV-Vis microspectrophotometry and infrared analysis were employed to compare fibers recovered in the trunk of a car to those of the blankets composing the wrapping in which the victims had been hidden. A "pseudo-1:1" taping permitted to reconstruct the spatial distribution of the traces and to further strengthen the support to one of the hypotheses. The Likelihood Ratio (LR) was calculated, in order to quantify the support given by forensic evidence to the explanations proposed. A generalization of the Likelihood Ratio equation to cases analogous to this has been derived. Fibers were the only traces that helped in the corroboration of the crime scenario, being absent any DNA, fingerprints and ballistic evidence.     

Testing Application of Geographical Information Systems,Forensic Geomorphology and Electrical Resistivity Tomography to Investigate Clandestine Grave Sites in Colombia,South America

Colombian forensic investigators required assistance locating clandestine burials of missing persons related to human right atrocities from 14 years ago. Geoscientific search methods were trialled, including a predictive spatial statistical model, using various input and database information, to select the most likely grave locations in difficult mountainous terrain. Groundwork using forensic geomorphology, near-surface geophysics (ERT) and subsequent probing identified suspect burial positions. One site was in mountainous terrain and the other in former school grounds, both difficult to access and in poor weather conditions. In the mountainous area, a negative resistivity anomaly area was identified and intrusively investigated, found to be a buried rock. In school grounds, after MESP and intelligence were used to identify a burial site, surface depressions were identified, and ERT datasets collected over the highest priority depression; intrusive investigations discovered a hand-dug pit containing animal bones. This approach is suggested for Latin American searches.     

Exploratory study on classification and individualisation of earprints

The FearID research project is aimed at the individualisation of earprints for the purpose of forensic research. The study presented here was carried out within the framework of this project. It intends to combine a review of what is known from literature on the classification and individualisation of earprints with results from a preliminary study of earprints. Possibilities for, and limitations to, the use of earprints in forensic investigation are addressed. Differences between eliminating a suspect, placing a suspect at a crime scene, and linking crimes by prints left at different scenes are considered.     

Application of forensic toxicology to the problem of domestic violence.

The role of the forensic toxicologist in helping to determine causes of death or in aiding in the resolution of "driving under the influence" or similar cases is well known and clearly understood. Less clearly defined is the position of the forensic toxicologist vis-à-vis other socially significant problems. However, as the 21st century approaches, it is worth considering how forensic toxicology can help in unraveling some of these problems. The problem of violence between intimates--that is, domestic violence--is a social problem in which it has been long felt that alcohol has played a part. Until now, though, no carefully controlled toxicological studies have been conducted to substantiate this or to determine whether other drug use is associated with domestic violence. At the San Francisco Medical Examiner's Office, toxicological data from both the victim and the suspect in 20 cases of domestic violence that ended in homicide have been gathered. It was found that alcohol or other drugs or a combination of these factors was invariably present in the suspect, the victim, or both. The implications of these results and how they can be used to develop a toxicological strategy to help reduce the most serious consequences of domestic violence are presented.     

探讨急性酒精中毒者的刑事责任能力

我国刑法第18条第四款规定"醉酒的人犯罪,应当负刑事责任。"自从上世纪80年代末期复杂性醉酒的类型从日本引进中国后,司法精神医学界逐渐放宽了相当一部分醉酒者的刑事责任能力评定标准。这似乎有悖于现行法的规定,为了使该范围的鉴定与现行法规保持一致,笔者从医和法的两维角度探讨了如何评定急性酒精中毒者的刑事责任能力。