Lighting was crucial, since the reconstruction was required specifically to ascertain whether the defendant could have actually seen what he stated. To verify the accuracy of the Max rendering engine, I checked the shadows cast by the sun in situ in three different months, including December--the month in which the murder was committed.
This was done using a luxmeter supplied by the forensics department, and I found that the simulation perfectly matched reality. The two cars were reproduced using construction drawings provided by their manufacturers.
Max Surface Tools was used to model the Lancia Y10, while the Fiat Tipo was modeled using NURBS surfaces and Surface Tools. In order to ensure that the virtual corpse had the same position as the real one, the police doctor worked with us to get a perfect match according to marks on the body. The next stage involved Prof. Fabio Dossi, a renowned optician, who worked with me to reproduce the effect of the defendant's visual impairment on the screen, based on medical examinations. Images as seen by healthy subjects were modified to represent the visual effect produced in subjects affected by the same condition as the defendant's.
Each image representing the defendant's visual field was put out of focus, strictly applying the blurring parameters that the doctor had identified. We thus reproduced what the defendant, given the twilight conditions and his serious sight impairment, could have seen in that specific place and time, the parking lot in front of the Borgomanero Cemetery in Novara, Italy at 5:03pm on 29 December 1997.
To get to this point, much image testing and modification had been done related to specific sight deficiencies. It was a long process, but we were now ready for the hearing. Since all this work had been carried out using my own equipment, five monitors identical to mine were set up in the courtroom to provide satisfactory viewing, and DPS Italia supplied two identical workstations equipped with the PVR (and later dpsReality) video editing card that I had used during development.
At crucial points during the demonstration, Prof. Dossi asked me to display on the monitor what the defendant could see, not in the twilight at the moment of the crime, but in hypothetical full brightness conditions. This showed that not even in such optimum conditions could the defendant have actually seen all he mentioned during his deposition. However, we had not yet proven the validity of the virtual model. The defendant's impairment needed to be related to his location, which was also determined from his deposition. During model development, we matched the scene shot with a video camera, positioned in the place indicated by the defendant at his eye height, with its twin virtual scene.
Overlapping the two, the images were identical. The court and jury were shown both the actual pictures of the area and their virtual reproductions, so that they could see the perfect correspondence. I also overlapped orthogonal views of the cars' technical drawings and their 3D reproductions to confirm the modeling accuracy. I then showed a series of overlaps of the actual video made by the forensic department and the reproductions, using a dissolve between them, to show that the 3D scene views matched the real views from several viewpoints.
Finally, I played my best card: a four-minute sequence which provided an overall view of the area to the court, the defense, and the prosecution. By the end of the hearing we had been able to prove and strengthen the prosecution's case, thanks to a meticulous reconstruction. The sentence was passed down on 23 February 1999. The defendant was found guilty of voluntary manslaughter and was sentenced to 20 years in jail, plus three years probation, and was required to pay 280 million lire (about us$140,000) to the victim's family. The verdict was subsequently confirmed by the Court of Appeal and the Court of Cassation.
Giuseppe Galliano has a degree in law from the State University of Milan, and has wide experience in working with 3D Studio for DOS and 3DS Max among a wide range of multimedia software and hardware tools, which he uses to provide all manner of production services. You can reach him at or visit www.giuseppegalliano.it (Flash required).
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