面像照片比对鉴定2例

随着科技进步及人们法制观念的增强，人面像比对鉴定的案件将增加。例如机场、银行、居民小区等如发案通过闭路电视监视系统所摄录相资料，与犯罪嫌疑人的面像进行比较；报刊杂志或其他宣传资料展示的人像与有关诉肖像侵权案当事人照片的比较。伪造的证件照片与犯罪嫌疑人面像的比较等。证件或档案照片与犯罪嫌疑人的照片比较鉴定，条件比较好一些，因为拍摄标准照的条件是类似的，两照片可资比较的内容较多。闭路电视监视系统所摄影像的比较，第一步是通过图像处理系统，提取录相带上的个人影像，提取到清晰的影像才能进行面像比较。这样提…     

利用图像处理系统检验添加笔画

当前，文检中涉及到墨水检验的案件越来越多，而在检材量较少时，对签字笔等笔迹的鉴定难度仍然较大。笔者曾受理一起案件，要求检验所提供的收条上日期字迹是否为一次形成，经采用扫描仪高分辨率扫描，通过图像处理的方法，得出了鉴定结论，效果较好介绍如下：１简要案情２０００年１月，朱某向某信用社还款６６００元，并从信用社经办人员刘某处取得收条一张。３天后，朱某又从该信用社贷款６６００元。同年１１份，信用社向朱某催还贷款时，朱某出示了一张日期为当年１１月份的收条，信用社认为此收条为１月份朱某还款时取得，经变动书写…     

浅谈野生动物案件中鸟类形态鉴定照片的拍摄

野生动物案件是指野生动物作为受害者的案件,随着野生动物及其制品走私的日益猖獗,人类环境保护意识的提高,我国对野生动物执法工作的加强,野生动物案件的发案率也呈逐年上升趋势。在森林违法案件中,尤其是野生动物案件中,具体涉及到鸟类的案件也越来越多。本文论述了野生动物案件中鸟类形态鉴定照片拍摄的必要性,并提出鸟类形态鉴定照片主要需拍摄整体侧面照片、鸟喙的照片、鸟脚的照片和其它特殊形态的照片。这些鉴定照片的拍摄将有助于远程指导森林公安的办案工作。     

现代摄像机DSP图像处理系统的设计

传统的数字图像处理通常采用图像采集卡,送PC机进行软处理。这不仅不够灵活,其处理能力还受到PC机和软件的限制。随着CCD与CMOS摄像机芯片工艺的改进和数字信号处理器DSP功能的提升,从而可形成数据量与计算量较大的图像硬处理。本文介绍现代固体摄像机基于DSP图像处理系统的设计,具体介绍系统设计的功能与指标要求、系统的结构组成、系统的硬件与软件设计(软件算法与系统优化)等。     

民事诉讼中利用真实印文伪造证据的系统鉴定

本文以四个案件为例,阐述了民事诉讼中利用真 实印文伪造证据的特点,如何对此类案件进行鉴定以及鉴 定时应注意的问题,最后提出了三点建议。     

利用真实印文签名变造欠条的系统鉴定

民事诉讼中当事人利用真实印文、签名伪造证据的情况日益增多,增加了鉴定的难度,本文以实际案件为例,运用系统鉴定法,从纸张、印文真伪及盖印时间、打印字迹、手写字迹、比对样本、重视案情调查了解等多个角度对如何鉴定此类案件做了经验性的总结和阐述。     

Color Separation in Forensic Image Processing Using Interactive Differential Evolution

Color separation is an image processing technique that has often been used in forensic applications to differentiate among variant colors and to remove unwanted image interference. This process can reveal important information such as covered text or fingerprints in forensic investigation procedures. However, several limitations prevent users from selecting the appropriate parameters pertaining to the desired and undesired colors. This study proposes the hybridization of an interactive differential evolution (IDE) and a color separation technique that no longer requires users to guess required control parameters. The IDE algorithm optimizes these parameters in an interactive manner by utilizing human visual judgment to uncover desired objects. A comprehensive experimental verification has been conducted on various sample test images, including heavily obscured texts, texts with subtle color variations, and fingerprint smudges. The advantage of IDE is apparent as it effectively optimizes the color separation parameters at a level indiscernible to the naked eyes.     

法医文证审查100例分析

通过100例法医文证审查案件的分析,发现在目前检察机关文证审查工作中,存在委托数量不足、委托程序不规范、送检材料不全面等问题;在送审鉴定文书中,也存在标准条文掌握不当、鉴定人基础知识欠缺和粗心大意等问题。同时发现,鉴定文书的规范化程度和采信率已经得到有效的提高;且规范化越高的鉴定机构,则其鉴定文书的准确率越高,被采信率也越高。目前有必要加强检察技术部门文证审查的技术水平,进一步积累办案经验,切实增强检察机关的法律监督能力。     

Evaluation of Lip Prints on Different Supports Using a Batch Image Processing Algorithm and Image Superimposition

This study aimed to develop and to assess an algorithm to facilitate lip print visualization, and to digitally analyze lip prints on different supports, by superimposition. It also aimed to classify lip prints according to sex. A batch image processing algorithm was developed, which facilitated the identification and extraction of information about lip grooves. However, it performed better for lip print images with a uniform background. Paper and glass slab allowed more correct identifications than glass and the both sides of compact disks. There was no significant difference between the type of support and the amount of matching structures located in the middle area of the lower lip. There was no evidence of association between types of lip grooves and sex. Lip groove patterns of type III and type I were the most common for both sexes. The development of systems for lip print analysis is necessary, mainly concerning digital methods.     

Individual Camera Identification Using Correlation of Fixed Pattern Noise in Image Sensors

Abstract:  This paper presents results of experiments related to individual video camera identification using a correlation coefficient of fixed pattern noise (FPN) in image sensors. Five color charge-coupled device (CCD) modules of the same brand were examined. Images were captured using a 12-bit monochrome video capture board and stored in a personal computer. For each module, 100 frames were captured. They were integrated to obtain FPN. The results show that a specific CCD module was distinguished among the five modules by analyzing the normalized correlation coefficient. The temporal change of the correlation coefficient during several days had only a negligible effect on identifying the modules. Furthermore, a positive relation was found between the correlation coefficient of the same modules and the number of frames that were used for image integration. Consequently, precise individual camera identification is enhanced by acquisition of as many frames as possible.     

Fast Source Camera Identification Using Content Adaptive Guided Image Filter

Source camera identification (SCI) is an important topic in image forensics. One of the most effective fingerprints for linking an image to its source camera is the sensor pattern noise, which is estimated as the difference between the content and its denoised version. It is widely believed that the performance of the sensor‐based SCI heavily relies on the denoising filter used. This study proposes a novel sensor‐based SCI method using content adaptive guided image filter (CAGIF). Thanks to the low complexity nature of the CAGIF, the proposed method is much faster than the state‐of‐the‐art methods, which is a big advantage considering the potential real‐time application of SCI. Despite the advantage of speed, experimental results also show that the proposed method can achieve comparable or better performance than the state‐of‐the‐art methods in terms of accuracy.     

模糊图像的最大熵恢复

首先介绍了由Hollis等人提出的最大熵图像恢复算法,该方法经过DavidS．C．Biggs等提出的方法加速后可以大大缩短处理时间。列举运用该加速算法恢复一些实际模糊图像的例子,其中包括运动模糊图像和离焦模糊图像,这些类型的模糊图像都是司法实践中常见的。良好的恢复结果证明了这一方法的有效性及其在司法领域中应用的可行性。     

Application of Infrared and Raman Spectroscopy in Paint Trace Examination

Raman spectroscopy has proved to be a promising technique in forensic examinations, where optical microscopy, micro‐infrared spectroscopy, and microspectrophotometry in the visible and UV range are used for identification and differentiation between paint traces. Often no organic pigments are detected using Fourier transform infrared spectroscopy, because their content in a trace is usually undetectable. Application of a micro‐Raman spectrometer equipped with several excitation lasers helps forensic experts in paint analysis enabling identification of main pigments. Three cases concerning comparative examination of car paint are discussed in detail. The comparison of Raman spectra of paint chips found on clothing of a victim or smears found on body of a damaged car to these of paint chips originated from the suspected car enabled us to identify the car involved in the accident. When no comparative material is available, the method can be useful in establishing the color and make of the car.     

论物证检验的数码影像接合重叠方法

数码影像的特征接合重叠比对是取代传统特征接合重叠法的重要方法之一,其在检验中具有明显的可行性及操作优势。     

A Comparison of Thresholding Methods for Forensic Reconstruction Studies Using Fluorescent Powder Proxies for Trace Materials

Image segmentation is a fundamental precursor to quantitative image analysis. At present, no standardised methodology exists for segmenting images of fluorescent proxies for trace evidence. Experiments evaluated (i) whether manual segmentation is reproducible within and between examiners (with three participants repeatedly tracing three images) (ii) whether manually defining a threshold level offers accurate and reproducible results (with 20 examiners segmenting 10 images), and (iii) whether a global thresholding algorithm might perform with similar accuracy, while offering improved reproducibility and efficiency (16 algorithms tested). Statistically significant differences were seen between examiners’ traced outputs. Manually thresholding produced good accuracy on average (within ±1% of the expected values), but poor reproducibility (with multiple outliers). Three algorithms (Yen, MaxEntropy, and RenyiEntropy) offered similar accuracy, with improved reproducibility and efficiency. Together, these findings suggest that appropriate algorithms could perform thresholding tasks as part of a robust workflow for reconstruction studies employing fluorescent proxies for trace evidence.     

机制版假币票面上印刷疵点的检验

目的分析假币票样上的印刷疵点,为串并假币机制版印制点提供科学依据。方法通过图文扫描和图象处理技术,获取假币票面上的印刷疵点信息,研究梳理不同票面上一致的疵点组合,寻找其与印版的相关性,继而推导与印制者的相关性。结果找到可以表征相同胶片版或PS版的不同冠字号码假币票样上一致的印刷疵点。结论可以通过图文扫描和图象处理手段得到印刷疵点特征。