Through the use of special technology, all details of the scene of the crime or incident can be recorded and processed according to requirements. Exact measurements can then be mapped for the investigation process and essential details can be reconstructed in the overall context of the event or criminal act. The various options include:
Creation of sketches
Special sketches and location representations are created by surveying with a 3D laser scanner or a photogrammetric survey of the location, possibly using images taken from a helicopter.
Volume determination
Determining the volume of goods transported or stored (e.g. illegal waste dump with pollutants) can be used in investigative proceedings, for example, to answer questions about the quantity of goods transported or stored and thus substantiate allegations.
Determining the direction of fire
When a firearm is used, it is usually of interest where the shooter fired from. Was the person in a vehicle or an adjacent object? Were other people at risk? The direction of the shot can be calculated using a 3D laser scanner process and thus the location of the shooter can be determined.
Determining the field of vision
A procedure similar to determining the direction of fire is used to determine the field of vision. Here, the location of witnesses, injured parties and/or suspects is determined and evaluated, taking into account the course of the crime described. The result enables statements and conclusions to be drawn about the persons' field of vision and possible impairments or influences.
Crime and crime scene visualization
Special photographic processes are used to create photorealistic documentation of crime and incident scenes. This makes it possible to depict rooms in their entirety and thus visualize the location from different directions and angles. This form of representation can be supplemented by other forms of processing in order to open up new assessment possibilities by changing the brightness, the lighting situation and the depth of field.
Display size calculation
The image size calculation can be used to calculate the size of the person or detail shown in the photo or video, if this is required for the determination.
A procedure for the operational and investigative support of the North Rhine-Westphalia police.
In addition to a photogrammetric measuring method and 3D laser scanner technology with a focus on surveying, the 45.2 (crime scene surveying) department of the NRW State Criminal Police Office also uses so-called HDR 360-degree photography for photorealistic documentation of crime and incident scenes.
The special digital HDR camera records rooms fully spherically and therefore in all directions at an angle of 360 degrees horizontally and 180 degrees vertically for fully spherical images.
The "High Dynamic Range" (HDR) process makes it possible to view the recorded image data in a very wide range of different brightness values and to very conveniently compensate for differences in brightness, such as those between light and shadow or between room walls and window surfaces. In contrast to previous recording options in conventional analogue and digital photography, in which bright image areas (e.g. windows) were irreversibly overexposed and dark image areas (e.g. walls or room corners) were underexposed and therefore details could no longer be recognized, HDR makes it possible to brighten or darken individual image areas at any time in the existing image recording.
In addition to the 16 mm standard fisheye lens, the technology can also be used with 28, 50 and 105 mm interchangeable lenses.
In addition to the option of zooming in and out, the system also has a fully calibrated photogrammetric measurement technique, which, however, requires two images to be taken 60 cm apart. The image data of the two images is stored in such a way that measurement sections can be displayed with dimensions in the fully spherical overall image by selecting the measurement points accordingly.
However, the camera lens is calibrated at the factory for a measuring range of 1 to a maximum of 10 meters.
In addition to the original test procedure for combining color photographs with 3D laser scans, this procedure is of course also made available from here to the state's police departments in relevant investigative cases, especially at crime and incident scenes.
The system is a valuable addition to the classic recording of crime and incident scenes. In addition to two-dimensional photography and videography, it is now possible to create an even more objective photorealistic representation of a location. From a specific location, an all-round view is guaranteed that allows any of the above-mentioned individual perspectives and no longer depends on subjectively selected photo angles and locations or on subjective direction for a video. This means that partial views that influence the overall impression can be avoided, as is the case, for example, in photo and film direction for dramaturgical reasons.
In this way, police processing, the public prosecutor's office, the courts and the defense can be offered a factually realistic overall depiction of a location, which reduces text descriptions to a minimum, reproduces the scene of the incident photographically in a timely manner and thus makes time-consuming and costly site visits unnecessary.