Forensic animation helps jurors see clear picture

12 jurors + 12 minds = 12 different ideas.

This is one equation trial lawyers face when presenting evidence in a courtroom. They are faced with the task of communicating information to a jury that creates the same visual image in all 12 minds. The answer in many cases is for-ensic animation.

Forensic animation is a tool which, when used effectively, can convey complex situations and scenarios in a comfortable and easily understood medium: television.

Forensic animation is a technically accurate computer-generated visualization of an event.

The presentation of the event can occur through three different types of forensic animation:

Demonstrative, which is a visualization of an expert's opinion;

Simulation, which examines a scenario representing what could have happened or what should have happened;

Tutorial, which educates or instructs the jury on a procedure or scientific principle.

One or all of these types of forensic animation can be used in a mediation or courtroom setting. Forensic animation is generally used in cases where somebody has sustained a life-altering injury. The cost range varies by case.

Three-dimensional models

When a forensic animation is created, the first thing the animator must do is create the three-dimensional models that are involved in the event. A three-dimensional model is a virtual model built in the computer according to dimensions and data provided by an expert, blueprints, physical measurements, or any other factual information such as MRIs or CAT scans.

In addition to the models such as hu-man figures, vehicles or aircraft, the surroundings (which the models interact with) must also be built in the computer. Surroundings include items such as road, signs, trees or buildings. When models have been created, colors are added to represent the real world objects. Once the models have been completed, they must be put into the virtual environment and animated.

Animating

Now that the models are built, the accident/crime scene must be created. This process is comparable to a stage production.

The actors, their props and the set would be considered the computer models while the stage would be the computer scene. The virtual scene must have virtual lights and cameras added.

The relationships between the objects must now be defined in the computer. For example, when reconstructing a car accident, the cars are animated with the correct speeds, accelerations and impact points. All of this information must be programmed into the computer for the animation to take place. This process is known as keyframing. Key-framing defines and stores the position of an object at a particular point in time, or more precisely, at one particular frame.

After the animator defines the key-frames, the computer then interpolates the path between these points similar to connecting the dots. The objects are then constrained to move along this path.

Rendering

When the animation is complete, the computer must create all of the individual images that will compose the movie. This referred to as an image sequence. Even a short computer animation will contain hundreds, if not thousands, of individual images combined into a movie file, often referred to as an AVI file. AVI stands for audio video interleave.

One second of animation requires 30 frames, or individually rendered images. Once all of the frames have been created, they are composited into an AVI file that can be played on computer or recorded to VHS tape for television.

The message

Trial exhibits are an investment, with powerful messages to be presented. For-ensic animation offers a new approach for the presentation of vital information.

In addition to presenting moving images, any frame of an animation can be captured and produced into a still graphic.

Animation is not the answer in every case. Without a strong case and key ex-perts to explain and utilize the animation as a tool, forensic animation becomes a flashy display of images with no supportive backbone.

When speaking to 12 different people with different education levels and backgrounds, forensic animation allows an increased level of communication. Not only does it portray the same visual to everyone, but it also allows complex situations and scenarios to be broken down and analyzed in smaller parts.

Technical testimony from experts can be put into laymen's terms, and basic visuals for everyone to understand.

(Michelle Beach is a forensic animation project manager with H Design Group in Springfield.)