A path to Central Asia > Digital Sound Archives > Digitization tecniques - Italian National Sound Archive

Digitization tecniques - Italian National Sound Archive

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  1. Digital resources
  2. Problems
  3. Strategies of preservation

Digital resources

Digital resources can be classified into two main categories:

  • digital versions of physical documents, obtained through the digitalization process (conversion of nondigital material into digital format).
  • born digital documents (newly created documents without physical counterpart)

In the field of digital sound, the process of transcribing analogical recordings is of main importance. The digitalization of physical media, such as 78 rpm records, wax cylinders, 33 rpm records, and magnetic tape, is a valid solution for storing and guaranteeing the preservation of content.

Moreover, many analogical players have practically ceased to exist and it is increasingly difficult to find stores selling equipment such as tape players, 78 rpm record players, and wax cylinder players.

Over time some analogical media reach critical levels of deterioration and the only way to preserve recordings is to copy the content onto different media in the shortest possible time. In such cases, digital technology seems to offer the best solution.

Digital technologies had a fast evolution over the last few years and there has been a sudden increasing in digitalization initiatives and projects in the sound archives world. Increasingly, the tendency has been to switch from traditional collections of physical documents to digital collections.

Advantages of digitalization are:

  • Networked information

Content is transferred from traditional documents in storerooms and archives to local or geographical network management systems, so that it can be simultaneously accessed in different places; online consultation.

  • Duplication without loss of quality

Data can be duplicated easily, without loss of content;

Data is copied without information loss or deterioration in quality.

  • Data preservation

The use of digital technology is a valid solution for the preservation of content stored on material considered at risk, (analogical tapes, 78 rpm records, wax cylinders, or old manuscripts and texts).

  • Content processing

               Restoration, editing, copies of different quality for consultation and dissemination

               automatic processing of information.

  • Content query and search systems; availability of information.
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Problems

In contrast to these huge advantages, there are, however, some weak points.

The rapid obsolescence of digital technologies, and media instability and fragility make digital objects vulnerable. The lifespan of digital materials can be surprisingly short and rapid technological progress creates problems to future access.

The risk is occured of "all or nothing" when even a small amount of digital data is lost; damaged digital data cannot be retrieved, content is completely lost. Nowadays, we can still listen to 78 rpm records that are over a hundred years old; if a 78 rpm record breaks we can try to save it by using restoration techniques. This does not happen with digital media; materials in general last just a few years; if we have a cassette with damaged digital data there is little we can do unless we have backup copies.

Specific risks in the preservation of digital data over time:

  • limited physical lifespan of data recording media (CDs, DVDs, floppy disks, etc.);
  • obsolescent decoding hardware (players of various types);
  • obsolescent data interpreting software (word processors, imaging programs, browsers, etc);
  • obsolescent hardware for running programs (microprocessors, computers, etc);
  • decontextualization.

Obsolescence

Technological obsolescence is the result of technological progress. As new technology comes along it replaces the one before; new data writing materials rapidly replace old ones and media players used until then are no longer produced. Software becomes obsolete as new versions come onto the market and the hardware needed for new software changes continuously. Consequently information depending on obsolete technology becomes inaccessible. Digital archive media last longer than technologies required to support them. The technology supporting specific devices changes before these become old.

In general is not a good idea to continue using old technology, except in special cases.

The problem of technological obsolescence means that content transfer must keep pace with technological advances.

Digital transcriptions from one generation of media to another do not produce data loss or deterioration in signal quality. Content quality can be guaranteed indefinitely.
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Strategies of preservation 

Long-term digital data preservation is the main priority for most audiovisual archives. Traditionally the lifespan of the physical material on which information is recorded has been the most important factor in preservation. With digital technology many other factors must be taken into account, such as metadata and the software and hardware environment. Furthermore the exponential speed of technological change is such that even the most fragile and least durable materials outlive the availability of players designed for them. In this sense, media fragility is less important for preservation than the problem of technological obsolescence. For example a floppy disk that contains data is practically unusable if the hardware required to read it is not available.

Let us look at the most widely used strategies to guarantee long term preservation and data access, to counteract rapid technological obsolescence and media fragility:

  • REFRESHING

Regular copying onto new media using automated systems (these systems are generally integrated into archives designed for the storage of large amounts of data). Information is copied onto new media before the old deteriorate. This is a short-term solution for the preservation of digital data. It depends on the lifespan of the chosen media.

  • DATA TRANSFER

Regular transfer of digital data from a configuration or generation of hardware and software to the next configuration or generation (data needs to be recorded in a format that is software independent).

Transfer is used to preserve digital data integrity and provide access in line with technological evolution. Every organisation should transfer their files to new updated hardware and software, guarantee complete system functionality and information integrity, guarantee and preserve metadata links, including information on software and hardware transfers, and adopt standards to guarantee long-term preservation.

Data transfer is an efficient solution and offers good guarantees of data preservation.

  • EMULATION

Replication of the software used in the original technological environment.

The advantage of emulation over transfer is that the original data is not altered in any way. What changes over time is the emulation of the hardware and software environment.

It is also an efficient method, because once the data is filed using metadata and software, no further action is needed except for refreshing operations.

  • TECHNOLOGY PRESERVATION - ENCAPSULATION

Data are preserved together with the hardware and software on which they depend.

Together with digital objects, everything that guarantees access to them is preserved. Documentation becomes fundamental: metadata describing the resource, software and hardware, and metadata containing information on data management and preservation.

  • BACKUP COPIES

Automatic backup procedures.

Backup copies are kept physically separated from the originals in a protected environment, with controlled temperature and humidity, away from the main archive.

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