Computer output on laser disk

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Computer Output on LaserDisk (also Computer Output to LaserDisk , common acronym COLD ) describes a process for the transfer of output data streams such as print data (English Computer Output ), which are generated in IT systems, into an archive system .

The term goes back to the mid-1980s. At that time, outputs from computer systems were often archived in the form of "COM" computer output on microfilm. With the advent of digital-optical storage media, the “COLD” process was specifically positioned against microfilm. The term "COLD" should evoke the association that a comparable, but more modern process than "COM" is used. The term “LaserDisk” goes back to the user-writable version of a Philips product (LD Laserdisc ), which was no longer on the market in the mid-1990s. However, the term that goes back to this product is still used in the document management industry. It now stands for different methods of automatic processing of data streams, lists, outgoing mail, etc. For this purpose, the term Enterprise Report Management or the acronym ERM is increasingly used in Anglo-American parlance .

Incoming mail versus outgoing mail

With the first commercial archiving systems in the 1980s, incoming mail (in paper form) was digitized using a scanner and stored as a raster image . The archiving of the outgoing mail, i.e. the self-generated documents, was initially dispensed with. With the increase in process or customer-oriented archiving, the need also increased to include outgoing mail. Since these documents were usually created on printers , it was a good idea to archive the print data yourself. Since this data is typically created in larger runs ( spool files ), the specialized method of archiving this print data has developed. Different strategies are used: storage as raw data, which is converted into a displayable document by calling up layout resources, storage in list form for structured reports and evaluations as well as structured display of the data in applications, and conversion of the data stream into individual PDF - or TIFF objects that visually correspond to the original documents sent.

Beginnings of COLD archiving

In the 1970s and 1980s, print data were usually simple line data that, similar to a typewriter, reproduced line by line and contained a control character at the end of the page to change the page. For archiving, index values ​​were tapped from this data at fixed positions in order to determine the invoice or customer number, for example. Such a fixed position was, for example, line 8, columns 40 to 48. The archive system saved this print data as a file together with these index values ​​and the position of the page within this file. The individual page was then copied from this file for display and displayed on a computer terminal . These functions were usually part of the scope of delivery of an archive system.

Modern COLD systems

With the beginning of the 1990s, the requirements for mass printing became more and more complex and accordingly optimized print data streams such as PCL , PostScript or AFP were developed that enable complex layouts . Saving such print data as a single file was therefore no longer practical in every case. Accordingly, modern COLD systems offer the following basic functions:

  • Separating documents with different numbers of pages,
  • Index determination via freely definable logic,
  • Conversion of the print data into a format suitable for archiving such as TIFF or PDF / A ,
  • Creation of special import files for different archive systems.

COLD archiving has thus become an important component of enterprise content management systems, which can be seen as the successor to the early electronic archive systems. COLD serves both to prepare the output for different formats and as an input for the provision of the outgoing mail in a holistic view of all electronic documents (virtual files). COLD processes are also used for the migration of data storage and the automated transfer of transaction data in document management solutions.

See also