Photographic Evidence Protocol: The Use of Digital Imaging Methods to Rectify Angular Distortion and Create Life Size Reproductions of Bite Mark Evidence

    Volume 47, Issue 1 (January 2002)

    ISSN: 0022-1198

    CODEN: JFSOAD

    Published Online: 1 January 2002

    Page Count: 8


    Bowers, CM
    Clinical Assistant Professor, University of Southern California School of Dentistry, Deputy Medical Examiner, Ventura County, CA

    Johansen, RJ
    Consultant in Forensic Odontology, Santa Barbara County Sheriff/Coroner, Santa Barbara, CA

    (Received 23 December 2000; accepted 3 April 2001)

    Abstract

    Bite mark evidence seen in skin injuries or objects is commonly photographed for evidentiary documentation, preservation, and analysis. Distortion in forensic evidence photographs diminishes the outcome of analytical procedures available to the forensic odontologist. Inaccurate positioning of the evidence, camera, or measurement reference scale creates perspective and parallax distortion of the captured image. These variables must be eliminated, if possible, to ensure reliable results derived from comparison of the suspect teeth and the bite mark. Detection and measurement of camera/evidence/scale misalignment is the threshold step in evidence evaluation, and is possible through digital imaging methods coupled with established methods. Correction (rectification) of perspective distortion is possible through the application of additional digital editing techniques. This study establishes type categories of perspective and parallax distortion seen in bite mark evidence, validates the use of the digital imaging tools of Adobe® Photoshop® to correct certain types of distortion, and establishes a forensic protocol to verify the accuracy of evidence photographs requiring dimensional accuracy.


    Paper ID: JFS15221J

    DOI: 10.1520/JFS15221J

    ASTM International
    is a member of CrossRef.

    Author
    Title Photographic Evidence Protocol: The Use of Digital Imaging Methods to Rectify Angular Distortion and Create Life Size Reproductions of Bite Mark Evidence
    Symposium , 0000-00-00
    Committee E30