Biggs Paul R, Evans Samuel T, Jones Michael D, Theobald Peter S
Cardiff School of Engineering, Cardiff University, Wales, UK.
Sci Justice. 2013 Sep;53(3):358-62. doi: 10.1016/j.scijus.2013.05.001. Epub 2013 Jun 20.
Human bite-mark analyses can play a prominent role in forensic case investigations, including those involving sexual assault. High-quality photographs routinely secure a link between a bite-mark and an individual's dentition. Access to around the clock forensic photography, however, is often limited, resulting in delay and/or missed opportunities to record valuable evidence. The emergence of Smartphone high-quality photographic technology now provides a previously unimagined opportunity to gather timely forensic photographic evidence. Problems can arise, however, due to the relatively poor quality of the photographs, as a result of many of those taking photographs having received little or no forensic photography training. This study compares unassisted photography with assisted photography, by a specifically developed camera application (App), to provide a standardised method for taking forensic photographs. An App, written in Java, was hosted on the Google Android Operating System, on a Samsung Galaxy SII Smartphone. Twenty-four volunteers participated in a study to photograph a pseudo bite-mark using three methods, (1) unassisted (as a control), (2) assisted by an ABFO No.2 right-angled photographic reference scale and (3) assisted by the App. The App, method (3), was shown to consistently outperform methods (1) and (2), demonstrating greater standardisation and precision (p<0.001). Analysis of the data showed the extent to which acquiring an accurate photograph depends on the image being orthogonal to the camera. It appears likely that the relatively inaccurate photographs acquired by methods (1) and (2), were as a result of deviation from the plane, orthogonal to the bite-mark. Therefore, the App was successful in ensuring that the camera was both orthogonal and at an appropriate distance, relative to the bite-mark. Thus, the App enhanced the abilities of non-experts to acquire more accurate photographs and created the potential to significantly improve the quality of forensic photographs.
人体咬痕分析在法医案件调查中，包括涉及性侵犯的案件调查中，可发挥重要作用。高质量的照片通常能确定咬痕与个人牙列之间的联系。然而，全天候获取法医摄影服务往往受到限制，导致记录宝贵证据出现延迟和/或错失机会。智能手机高质量摄影技术的出现，现在提供了一个以前无法想象的及时收集法医摄影证据的机会。然而，由于许多拍摄照片的人很少或没有接受过法医摄影培训，照片质量相对较差，可能会出现问题。本研究比较了无辅助摄影和通过专门开发的相机应用程序（应用程序）进行的辅助摄影，以提供一种拍摄法医照片的标准化方法。一个用Java编写的应用程序，搭载在三星Galaxy SII智能手机的谷歌安卓操作系统上。24名志愿者参与了一项研究，使用三种方法拍摄一个模拟咬痕，（1）无辅助（作为对照），（2）由ABFO No.2直角摄影参考标尺辅助，（3）由应用程序辅助。结果表明，应用程序方法（3）始终优于方法（1）和（2），显示出更高的标准化和精度（p<0.001）。数据分析表明，获取准确照片的程度取决于图像与相机的正交性。方法（1）和（2）获取的相对不准确的照片，可能是由于偏离了与咬痕正交的平面。因此，该应用程序成功地确保了相机相对于咬痕既正交又处于适当的距离。因此，该应用程序提高了非专业人员获取更准确照片的能力，并创造了显著提高法医照片质量的潜力。
