Transcript of "Digitisaing oral history by Sally Hone"
Digital practice update: digitisation and digital preservation 15 February 2011 DIGITISING SOUND RECORDINGS Sally Hone Oral History Curator Original Materials Branch
The value of oral history <ul><li>Oral history in this Library documents the lives of people living in New South Wales. It frequently complements the written record and may expand it further. It also gives a voice to those who may previously have been denied the chance to contribute to the written or printed recording of history. </li></ul><ul><li>The recording by an informed interviewer of people's experiences provides insights into society, not only to its history, but changing values and attitudes. </li></ul>
The collection <ul><li>Prior to the establishment of the oral history program in 1991, the Mitchell Library had been receiving oral history and sound recordings for some years – usually as part of a larger collection of papers. </li></ul><ul><li>After 1991 the Library actively sought material to add to the oral history collection – by donation or purchase </li></ul>
The collection <ul><li>The Ethnic Affairs Commission Oral History Project, interviews conducted with migrants who arrived in Australia in the early 1950s </li></ul><ul><li>The Sydney Harbour Bridge Builders interviewed 50 years after the Bridge was opened </li></ul><ul><li>Corporate histories including projects with employees of Colgate-Palmolive, Bonds Industries and Woolworths Limited. </li></ul><ul><li>Interviews with members of the Jewish community by historian Suzanne Rutland. </li></ul><ul><li>Interviews with early women scientists. </li></ul><ul><li>Interviews with members of the Communist Party of Australia </li></ul><ul><li>Institution of Engineers Oral History Project (on-going) </li></ul><ul><li>Interviews with architects, writers, artists, early social services professionals, former Library staff and other professionals </li></ul><ul><li>Special recordings include the Writers' Festival during the period that they were held at the State Library </li></ul><ul><li>The Sydney Maritime Museum Oral History Project (now Sydney Heritage Fleet), where over 100 interviewees speak of their maritime lives around Sydney Harbour. </li></ul>
Oral History Collection at SLNSW <ul><li>COLLECTION – not commissioned </li></ul><ul><li>All formats going back to 1950s </li></ul><ul><li>Mostly analogue – cassette and reel-to-reel </li></ul><ul><li>Some DAT (digital audio tape) and CDs also microcassette and minidisc </li></ul><ul><li>Up to 10,000 hours of recordings </li></ul>
Condition of the collection <ul><li>Like many oral history collections – it is a collection, not commissioned, so there is a great variety in quality, type of recording, carrier etc. </li></ul><ul><li>It has been kept in good storage conditions – cool, consistent humidity, standing upright on shelves </li></ul><ul><li>Some reels are displaying ‘sticky shed’ </li></ul>
The imperative of digitisation <ul><li>Obsolescence of play back equipment </li></ul><ul><li>the threat of carrier degradation </li></ul><ul><li>In general, audio will have a shorter life-expectancy than that of good quality traditional text materials. </li></ul><ul><li>In addition, audio carriers are more vulnerable to damage caused by poor handling, by poorly maintained or malfunctioning equipment and by poor storage than conventional text documents. Due to the high density of information, digital carriers are generally more vulnerable to loss of information through damage than analogue carriers. If a carrier is damaged by poor storage or mishandling, the information may be lost. This applies to both digital and analogue material. </li></ul>
Preparation <ul><li>Digitisation takes planning and preparation </li></ul><ul><li>Survey the collection – prioritise it. What is most valuable content? What in most danger of being lost due to damage or degradation? What most often requested? How many hours are there? What formats – cassette, reel, DAT etc </li></ul><ul><li>For large collections it is recommended that you create a data base that later can be migrated to a digital content management system/catalogue </li></ul>
Planning <ul><li>Budget – what will it cost? Who will pay? Grants available? </li></ul><ul><li>IT – storage available (audio files are large – 1 hour roughly 1 gigabyte)? </li></ul><ul><li>Do you have technical expertise for content management, file ingest and ongoing storage and backup? </li></ul>
Free tools for assessing preservation needs of audio collections <ul><li>see http://agogified.com/289 </li></ul><ul><li>which has links to four preservation assessment tools that can be down loaded. Even if you don’t use them, worth reading for lots of valuable information on cassette and other carriers </li></ul>
Digitisation –what is it ? <ul><li>digitizing means simply capturing an analog signal in digital form </li></ul><ul><li>A digital audio system starts with an Analogue digital convertor (ADC) that converts an analog signal to a digital signal </li></ul><ul><li>The ADC runs at a sampling rate and converts at a known bit resolution. </li></ul><ul><li>Sample Rate refers to how many times per second the audio information is captured. </li></ul><ul><li>Bit Depth refers to how much information is captured with a sample. </li></ul><ul><li>For example, CD audio has a sampling rate of 44.1 kHz (44,100 samples per second) and 16-bit resolution for each channel. </li></ul>
Information about digital sound technology <ul><li>Available in books and on web sites. Look at wikipedia sites such as </li></ul><ul><li>http://en.wikipedia.org/wiki/Audio_file_format </li></ul><ul><li>Or WikiRecording, a free online guide to audio recording, editing, mixing, and mastering </li></ul>
Digitisation - standards <ul><li>International Association of Sound and Audiovisual Archives - IASA </li></ul>http://www.iasa-web.org/
Digitisation standards <ul><li>As the source is analogue, it is desirable to record the best copy possible, which means using the uncompressed WAV format. If possible, record at 24 bit 48 kHz stereo quality. </li></ul><ul><li>Apart from the limitations of the original recording, quality depends on the playback setup, the digital capture software and format, and the hardware that connects the two. </li></ul>
International Association of Sound and Audiovisual Archives Technical Committee Standards, Recommended Practices and Strategies IASA-TC 03 ASA <ul><li>Sound archives have to ensure that, in the replay process, the recorded signals can be retrieved to the same, or better, fidelity standard than was possible when they were recorded. </li></ul>
Audio to digital conversion <ul><li>Desk top – home businesses – may be cheap, but may not be of high standard – playback machine (CD, cassette, reel to reel) plugged into computer sound card, or through an audio capture device – and saved using audio software such as Audacity. NOT RECOMMENDED </li></ul><ul><li>Use a professionally set up digital audio workspace - best quality playback equipment and high quality analogue to digital converter eg DAD, professional software and computers wired to location outside the studio </li></ul>
Conversion <ul><li>Many A to D products out there </li></ul><ul><li>Need sound specialists – advice – and do homework </li></ul><ul><li>Getting harder to get playback equipment eg Studer or Otari reel to reel players and Tascam etc professional cassette players </li></ul><ul><li>There are a few specialists who collect and maintain this equipment </li></ul>
IASA guidelines <ul><li>Adhere to highest possible standards </li></ul><ul><li>A to D converter ‘the most critical piece of technology in the digital preservation pathway’ </li></ul><ul><li>Specifications for A to D converters - check for distortion, signal to noise ratio, frequency response, clock accuracy, jitter – look at IASA publication </li></ul>
File formats <ul><li>Use WAVE ( file extension .wav) developed by Microsoft and IBM – widely used in professional audio industry - likely that there will be long term acceptance of the format </li></ul><ul><li>BWF.wav files are an extension of .wav. Benefit of this format is that metadata can be incorporated into the headers which are part of the file </li></ul><ul><li>MP3 or other ‘lossy’ formats not to be used. They employ data reduction during transfer and parts of the primary information is irretrievably lost </li></ul>
METADATA <ul><li>Once digitised, the original carrier eventually goes. Archives need, therefore, to record in a systematic manner the relevant secondary information contained in the original document so future users can be sure of the authenticity of the primary data. </li></ul><ul><li>Metadata – documentation – details all technical, process, provenance and descriptive aspects of a recording </li></ul>
Essential metadata <ul><li>Unique identifier </li></ul><ul><li>Description (identifies content of audio file) </li></ul><ul><li>Technical data- format, sampling and bit rate, file size </li></ul><ul><li>Coding history – original item and process and technology of creating the digital file being archived </li></ul>
Collection management <ul><li>At SLNSW – audio will be stored in mass digital storage system. It will be managed through a digital asset management system (DAMS). Workflows track ingest of digital files and access copies. </li></ul><ul><li>This still being worked on </li></ul><ul><li>Smaller collections - will require more simple systems </li></ul><ul><li>CD/DVD not reliable for long term storage </li></ul>
Benefits of digitisation <ul><li>Preservation beyond the original carrier </li></ul><ul><li>But this has to be managed </li></ul><ul><li>Once digitised at high resolutions, can make copies that have smaller file size – MP3 copies </li></ul><ul><li>Can easily burn to CD for reference copies or stream on website </li></ul><ul><li>Use digitised content to enhance exhibitions and displays </li></ul><ul><li>Greater access – anyone can access through the internet </li></ul>
Benefits - examples <ul><li>National Library of Australia –advanced digitisation program. See online. Note permissions/restrictions </li></ul><ul><li>For example </li></ul><ul><li>Forgotten Australians and Former Child Migrants oral history project </li></ul><ul><li>http://catalogue.nla.gov.au/Record/4707359?lookfor=forgotten%20australians%20%23[format:Audio]&offset=1&max=50 </li></ul>
Benefits <ul><li>Transcripts and timed summaries can be integrated with online sound </li></ul>
Digitally born recordings <ul><li>Briefly: collect digital content in the future </li></ul><ul><li>Again, record at highest possible quality -24 bit 48kh - and don’t compromise on sound recording equipment – digital recorders and good microphones </li></ul><ul><li>Manage new digital content in DAMs, store on hard drive with backup </li></ul>
New digital content <ul><li>Once system set up, if you have the storage space, can accept more new material. Easier to catalogue, transcribe or make time logs. </li></ul><ul><li>Set standards – train interviewers, give advice on equipment, lend out equipment if possible. </li></ul>
Oral History Association of Australia NSW has good information on equipment and project development etc see http://www.ohaansw.org.au /
Also this is a very useful publication Oral History Handbook 5th edition, 3rd impression, by Beth Robertson $20 for OHAA members available at seminars and workshops Mailed Orders: $28, $20 members and Bulk orders of 10 or more $20 Mail your cheque to: OHAA-SA Inc, PO Box 3113, Unley SA 5061 The Oral History Handbook has been published by the South Australian Branch of the Oral History Association since 1983. It is well established as the national standard. The author draws on 25 years experience of practising and teaching oral history techniques and preserving sound recordings. In this newest printing (5th edition, 3rd impression) Beth has revised five pages which update information on digital technology.
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