DEEN
Dipl.-Biol. Bastian J. Hirthammer
Forensic Anthropology

Technical preparation of measurement image data

Measurement image data and conversions

In traffic proceedings, measurement image files are often available only in the manufacturer’s original format. The initial task is therefore decryption, export, conversion into common image formats, and the traceable documentation of the original data.

The service is directed in particular at courts, public prosecutors, police authorities, regulatory authorities, legal counsel, and other bodies that receive measurement image files in their original format. The aim is conversion into a common image format that remains readable on ordinary computers and can be provided in a traceable form for further work.

It does not replace an expert report, but it may be a prerequisite for later expert work. Technical conversion remains separate from the later substantive assessment of the image material.

Measurement images · Function of the preparation

Result of conversion

The technical preparation of measurement image data is an upstream working step. Its aim is a traceable, as far as possible low-loss basis for viewing, comparison or further expert work.

The service mainly concerns proprietary, signed or encrypted source files. It includes conversion into common image formats, separation between source file, exported working copy and later processing stages, and checking whether image, key, token or accompanying files are required.

Where a system generates several image sources, the work also includes assigning measurement images, supplementary photos, radio photos or other image components. Restrained technical preparation may be added, for example brightening, tonal-value adjustment or enlargement for better legibility.

Measurement images · Workflow

Typical course

The starting point is the question which original format is present and with which viewer or manufacturer environment the data can be made readable. This is followed by decryption or export, examination of technical quality, and provision in a format suitable for further work. It must be documented in a traceable way which file formed the basis and which steps were taken.

Especially in traffic proceedings, this clear separation between source file, export, and later expert examination can be decisive.

Measurement images · Technical starting point

Source data

Systems, source data and accompanying files

In practice, systems and data stocks from ESO, Gatso, Jenoptik, Leivtec, Vitronic, VDS and other common formats play a role. The starting point is the available data stock: original data, quality-preserving export, printout or screenshot.

Typical system environments guide the technical preparation. In the ESO area, ES 3.0 and ES 8.0 are treated separately; with ES 8.0 the associated JPEG is usually also required for practical viewing, whereas with ES 3.0 the original case data set is more central. In the XV3 / Leivtec environment, processing depends on supplied case files, viewer components or export components. In the case of SBF and BIF files from the Jenoptik / Robot area, signed event files, BIF image data and the associated evaluation software are needed. TUFF files from the Vitronic / PoliScan area may additionally depend on viewer, token or password; in the VDS environment, export routes, accompanying files and later readability are central.

For practice, this means that file extension alone is not enough. Whether a data set can be opened and assigned depends on viewer, token, key and additional files as well as on the separation between source file, export and working copy.

Typical cases are signed original data, several image sources such as measurement image, supplementary photo and radio photo, and software-bound exports into common image formats. Required are device type, software status and the supplied data carrier.

Measurement images · Practical relevance

Practical relevance in measurement image files

In regulatory offence proceedings, measurement images may be stored as signed, encrypted or proprietary source files rather than ordinary image files. In some systems image and measurement data are stored together; in others separate measurement images and supplementary photos must first be allocated correctly.

For procedural practice, the separation between original measurement file, software-side export and later working copy is central. Technical preparation makes the material traceable and transferable. Substantive examination of the image material is instructed separately.

Handling of data

Transmitted exhibits and source data are processed exclusively in relation to the proceedings. Transfer or publication takes place only on a legal basis or express instruction.

Limits

Conversion improves readability and traceability. It facilitates further work with the material. The evidential value follows the source material.

Measurement images · Clarifying the assignment

Initial enquiry

For an initial technical review, the measurement system or file format, the proceedings and the aim of the preparation are usually sufficient.

Helpful for the initial technical review
  • original files and accompanying files
  • information on the measurement system
  • any existing export files
  • additional images or overview photographs
  • details of the available viewer or software version