title: Crime Scene Reconstruction Using a Fully Geomatic Approach.
abstract: This paper is focused on two main topics: crime scene reconstruction, based on a geomatic approach, and crime scene analysis, through GIS based procedures. According to the experience of the authors in performing forensic analysis for real cases, the aforesaid topics will be examined with the specific goal of verifying the relationship of human walk paths at a crime scene with blood patterns on the floor. In order to perform such analyses, the availability of pictures taken by first aiders is mandatory, since they provide information about the crime scene before items are moved or interfered with. Generally, those pictures are affected by large geometric distortions, thus - after a brief description of the geomatic techniques suitable for the acquisition of reference data (total station surveying, photogrammetry and laser scanning) - it will be shown the developed methodology, based on photogrammetric algorithms, aimed at calibrating, georeferencing and mosaicking the available images acquired on the scene. The crime scene analysis is based on a collection of GIS functionalities for simulating human walk movements and creating a statistically significant sample. The developed GIS software component will be described in detail, showing how the analysis of this statistical sample of simulated human walks allows to rigorously define the probability of performing a certain walk path without touching the bloodstains on the floor.
authors.affiliation: Politecnico di Torino, DITAG, C.so Duca degli Abruzzi, 24 - 10129 Torino, Italy.
authors.forename: Eros
authors.initials: E
authors.lastname: Agosto
authors.affiliation: ITHACA (Information Technology for Humanitarian Assistance, Cooperation and Action), Via P.C. Boggio, 61 - 10138 Torino, Italy. andrea.ajmar@ithaca.polito.it.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ajmar
authors.affiliation: Politecnico di Torino, DITAG, C.so Duca degli Abruzzi, 24 - 10129 Torino, Italy.
authors.forename: Piero
authors.initials: P
authors.lastname: Boccardo
authors.affiliation: ITHACA (Information Technology for Humanitarian Assistance, Cooperation and Action), Via P.C. Boggio, 61 - 10138 Torino, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Giulio Tonolo
authors.affiliation: Politecnico di Torino, DITAG, C.so Duca degli Abruzzi, 24 - 10129 Torino, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lingua
keywords: Crime scene; GIS; bloodstain; footprint; human walk