IASA TC 03 and TC 04: Standards Related to the Long Term Preservation and Digitisation of Sound Recordings

Transcription

1 IASA TC 03 and TC 04: Standards Related to the Long Term Preservation and Digitisation of Sound Recordings Muzeum a změna III. / The Museum and Change III. Prague,17 th 19 th February 2009

2 Introduction Contents IASA TC03 Basic principles IASA TC04 Basic principles How can these guidelines be practically implemented? Some approaches in practice

3 Introduction The tasks of sound archives : h Acquisition h Documentation h Access h Preservation IASA-TC 03: The primary task is to preserve the information placed in the care of the collection Web version 03 Version 3 (2).pdf

4 Introduction Traditional text documents and museum objects: h Digitisation is a tool for making cultural contents accessible h Original documents/ objects are preserved h Digitisation is an indirect measure for preservation Audio (and video) recordings: Digitisation indispensable for long term preservation

5 IASA TC03 Basic Principles h All audio-visual carriers are instable and vulnerable and therefore prone to decay h Except metal matrices and glass masters, audiovisual carriers have an even shorter life expectancy than paper-based documents

6 IASA TC03 Basic Principles h Cylinders become brittle and mouldy h Instantaneous discs reach end of life h Historical tapes become brittle and unplayable h Modern tape suffer from pigment binder degradation h Latest tape generation endangered by pigment oxidation h Recordable optical discs (CDs, DVDs) most endangered carriers of all

7 Cylinder degradation

8 Instantaneous disc

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10 Ultimate state of pigment binder degradation

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12 IASA TC03 Basic Principles h Audio and video recordings are machine readable documents h Even documents in perfect condition would be useless without replay machines h Life cycles of formats became ever shorter Audiovisual carriers are endangered by format obsolescence! Obsolescence of formats and replay equipment considered to even higher threat than carrier degradation

13 Format obsolescence and availability of equipment - audio format obsolete equipment now soon cylinders x specialist only coarse groove discs x specialist only micro groove discs (vinyls) x fading out quarter inch tape x fading out micro cassettes x fading out compact cassette?? R-Dat x fading out MiniDisc??

14 IASA TC03 Basic Principles Safeguarding the information By preservation of the carrier (& equipment ) Life of carriers cannot be extended indefinitely, but physical and chemical integrity must be preserved as long as possible By copying the information Long-term preservation of information can only be achieved by subsequent, lossless copying from one information carrier to the next Lossless copying can only be achieved digitally Analogue contents have to be digitised first

15 IASA TC03 Basic Principles Unmodified extraction of the entire document, the intended signal plus the unintended and undesired artefacts Aesthetic improvements must only be made in a second process on the basis of an objective archival master Signal extraction from analogue carriers determines the quality of the document for the rest of it s life Transfer technologies could improve, storage capacity is increasing, quality expectations are growing Keep the originals whenever possible!

16 IASA TC03 Basic Principles Transfer is time consuming and expensive, and unlikely to be done again consequently: original signals must be extracted and transferred in the best possible quality!

17 IASA TC03 Basic Principles h Digital long term archiving permanent migration h Running costs Hardware, Software (updates, licences), personnel,... h Complete change of archival life...no way back...

18 IASA TC03 Basic Principles Digitisation project must seek a compromise between urgency factors: h need for access h carrier decay h format and equipment obsolescence h Retarding factors h present high cost, lack of budget h technical improvement: transfer and digital preservation

19 IASA TC04 Basic Principles Audiovisual documents contain primary and secondary information Primary: content, signal, essence Secondary: associated materials and information, meta data, technical representation All kinds of information are part of the document and must be preserved Some technical information is lost in conventional transfer processes

20 IASA TC04 Basic Principles Metadata Background Key Digital Principles and Standards Unique and Persistent Identifiers Signal Extraction from Originals Preservation Target Formats and Systems

21 IASA TC04 Basic Principles Key Digital Principles and Standards Use of high quality components: h Stand alone A/D converter - minimum specifications Linear PCM Minimum 48 khz 24 bit.wav BWF No data reduction ( compression ) for analogue or linear digital originals

22 IASA TC04 Basic Principles Signal Extraction from originals: Use of the original for transfer - selection of best copy Cleaning, physical/ chemical restoration Choice of playback equipment Choice of playback parameters (speed, equalisation) Correction for misaligned recording equipment Removal of storage related artefacts Digitisation

23 IASA TC04: Basic Principles h Capturing of Metadata...and Metadaten and Metadata Automatically??? Manually???? Or a combination????

24 Practical Implementation for small scale approach Outsourcing vs. In-house? Serviceprovider vs. internal staff? Automatic transfer system vs. manual transfer?

25 Practical Implementation for small scale approach Minimum size of the collection (critical mass), increase of the collection to expect, not too many different formats to cover individual in-house tranfer is cost-effective, especially for research/ heritage institutions Point of intersection: ~ hrs of audio...provided that Educated (scientific and/or technical) staff with knowledge of the collection is available Cooperation with local IT specialists is possible

26 Assessment of the Collection

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29 Assessment of Existing (?) Metadata Structure

30 Developing a Preservation Plan Proposing a prioritised sequence of actions, based on different urgencies for different parts of the collection Definition of equipment needed Designing a business plan of investment Calculation for a step-by step solution small(est) scale approach

31 Developing a Preservation Plan Setup of infrastructure - Analogue replay equipment - Maintainance equipment - Digitisation workstations - Access stations - Server - Database Training of personnel IASA Training & Education Committee

32 To start with: Archive file: WAVE-Format (24Bit/96kHz) Browsing-copy MP3 (128kbps) Access copies via external A/D- Converter A single LTO drive or a small autoloader for making backups on data tape Single DAW with firewire/usb attached desktop RAID

33 Access Station Ingest-Station via external A/D- Converter Network switch Audio-File Server Ingest-Station via external A/D- Converter LTO autoloader

34 Special Problem: Preserving Video Art

35 Preservation of Material Pictures with AV Functionality

36 Thank You!