- Technological process of digitizing library collections
- Digital collections, scholarship and the Lab at KB National Library of the Netherlands
Metamorfoze Preservation Imaging Guidelines, The what, why & how.
Metamorfoze the program
Metamorfoze is the Dutch national program for the preservation of paper heritage. The program is an initiative of the Ministry of Education, Culture and Science. The Metamorfoze program was started in 1997 and is a program operated by KB, National Library of the Netherlands.
Metamorfoze Preservation Imaging Guidelines
The Metamorfoze Preservation Imaging Guidelines should be regarded as the image quality standard of Metamorfoze Preservation Imaging mass digitization projects. That means that all Metamorfoze Preservation Imaging digitization projects are to comply with these Guidelines.
The Metamorfoze Preservation Imaging Guidelines relate solely to the image quality of a so called first-generation camera or scanner file. The file format of this first-generation file must be a TIFF uncompressed group 6 file or a JPEG2000 file. This first-generation file must contain an embedded color space of eciRGBv2 or Adobe RGB (1998). The bit depth of this first-generation RGB file must be 8 or 16 bit per color channel. This first-generation file is referred to as the preservation master.
The basic principle of the Metamorfoze Preservation Imaging Guidelines is that all the visible information of the original must be visible in the preservation master. This basic principle, what you see is what you get, is granted by objectively measurable image criteria and objective measurements in all three Metamorfoze quality levels like in ISO/TS 19264-1 level A. The technical term and formula that is used to grant this basic principle is the gain modulation. The tolerance level for the gain modulation in the hight light area, applied to all three quality levels, is 80% – 108%.
The three Metamorfoze quality levels are: Metamorfoze Full, Metamorfoze Light and Metamorfoze Extra Light.
Quality level Metamorfoze Full is written to digitize originals that can be seen as works of art, like letters and manuscripts but also paintings and pictures.
Metamorfoze Light is written to digitize letters, books, newspapers, manuscripts and technical drawings.
Metamorfoze Extra Light is written to digitize bitonal originals only.
The reason to grant this basic principle that is strictly applied, and with the same tolerance levels, to all three Metamorfoze quality levels, is that the transfer of information must be complete, since the originals are subject to autonomous decay and will not be used anymore after they have been digitized.
Digitization according to the Metamorfoze Preservation Imaging Guidelines means that a strict protocol of quality control and quality assurance (QC & QA) has to be implemented in the daily work flow. It is only allowed to digitize the originals after the scanners or cameras are approved to meet the guidelines. So working according to the Metamorfoze Preservation Imaging Guidelines means that you have detailed insight in the image quality performance of your systems during digitization. And that the authenticity of your originals and all the visible information is robustly secured by daily objective measurements.
The daily objective assessment has to be carried out with the help of technical targets and software. The objective assessment is an essential and indispensable part of the Metamorfoze Preservation Imaging Guidelines. Besides the method of objective assessment, a preservation master must also always be subjected to a visual check for completeness and possible artefacts.
Since its publication in 2012 the guidelines are used worldwide by the cultural heritage community and by manufacturers of scanners and cameras.
ISO/TS 19264-1 was published in 2017. In this technical specification drawn up by ISO working group ISOTC42 JWG 26, specifications are provided for the digitization of cultural heritage. This ISO specification is based on the Metamorfoze Preservation Imaging Guidelines, the FADGI guidelines, and on image technological research and new insights.
Version 2.0 of the Metamorfoze Preservation Imaging Guidelines is under construction and follows on from the new developments described in ISO/TS 19264-1.
A prepublication is available on request only.
Hans van Dormolen
Hans van Dormolen is the founder of Hans van Dormolen Imaging & Preservation Imaging (HIP). He is working internationally as an independent imaging consultant in the cultural heritage community. He is the author of the Metamorfoze Preservation Imaging Guidelines, version 1 and he is currently writing version 2. Hans is also the designer of CET 357 and co-designer of UTT. Hans is a member of ISO TC42 JWG26 and IS&T. He received an IS&T Service Award for his work in objective capture practices for cultural heritage imaging in 2014. See more information on www.preservationimaging.com