7.4 Basic Metadata
7.4.1.1 Chapter 3 Metadata, outlines the requirements of documentation and management of a collection. As has been stated, metadata is pivotal to all aspects of the life cycle of a digital audio object, and paying strict attention to describing all aspects of the collection is one of the more important steps in its preservation. A detailed metadata record of all technical, process, provenance and descriptive aspects is a vital part of the preservation process. However, it is recognised that there is often a technical imperative to preserve audio collection material, and that this may well be before a metadata management system or policy has been developed. The following very basic recommendations are intended as a first step, a collection of data which is necessary to manage the file, or which must be captured or it would otherwise be lost:
7.4.1.1.1 Unique Identifier: Should be structured, meaningful and human readable as well as unique. A meaningful identifier can also be used to relate objects like: master or preservation files and distribution copies, metadata records, series, etc where a sophisticated system will manage that in the metadata.
7.4.1.1.2 Description: Description of the sound sequence. A small amount of text to simply identify the content of the audio file.
7.4.1.1.3 Technical Data: Format, sampling rate, bit rate, file size. Though this information can be acquired later, making it an explicit part of the record allows management and preservation planning of the collection.
7.4.1.1.4 Coding History: In BWF a number of discrete lines of information describing the original item and the process and technology of creating the digital file that is being archived. (See also 3.1.4 Metadata).
7.4.1.1.5 Process errors: Any error data which the transfer system can collect which describes failings in the transfer process (e.g. uncorrectable errors in CD or DAT transfers).
7.4.1.2 The information described in Unique Identifier, Description, and Technical Data can be recorded in Dublin Core records or the BWF headers. Coding History and Process errors can be recorded in the BeXT chunk of the BWF headers or in related XML encoded documents. The date, and if necessary, time of transfer should be recorded into the BWF header, and the date, and if necessary, time of ingest into the repository should be recorded in the metadata management in the repository. In some circumstances the timestamp information that relates components of a multi¡part recording will be mandatory. It is generally advisable to include time and date information with every event or digital object.
