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AUDIOVISUAL ARCHIVING: MAGNETIC MEDIA
What is magnetic media?
Handling and care
Risk factors and warning signs
Basic prioritization and identification
Key metadata and cataloging
Metadata standards
Moving toward access
WHAT IS MAGNETIC MEDIA?
FILM
VIDEO
RULES FOR HANDLING AND STORAGE
Avoid touching the magnetic tape
Store tape vertically inside its case
Rewind or fast-forward cassettes to the beginning or end for storage
Keep cool and dry, but not frozen (40°-65° F, 25%-50% RH, no fluctuation)
Inert plastic containers are best
Engage record protection mechanisms
RECORD PROTECTION
WARNING SIGNS
INVISIBLE DAMAGE
Sticky shed syndrome
Dropout
Tape scratches
Binder loss
OTHER INVISIBLE FACTORS
Recording standard
LP mode/SP mode
Playback environment
FORMATS
COMPONENT, S-VIDEO AND COMPOSITE
Component:Luminance
Red (Pr)Blue (Pb)
All sent separately
S-Video:Luminance
Chrominance
Light separated out, all colors sent
together
Composite:
Everything except audio sent in one combined signal
ANALOG TAPE
Linear information storageAnalog electrical impulses recorded onto tapeCannot be copied exactly – duplication and digitization always results in information loss
DIGITAL TAPE
Still linear Digital information recorded onto tapeCan be duplicated exactly – to other tapes or as a file
IDENTIFYING INFORMATION
FORMAT-BASED TRIAGE
Highest priority:older formatsobsolete formatssmall formats (fragile tape)master material
production chain: ¾”, Betacam or DV masters
VHS or DVD access copies
KEYWORDS TO LOOK FOR
Camera Original
Master
Edit Master
Original Footage
Viewing Copy
Rough Cut
Dub
Types of Metadata
• Descriptive metadata• Administrative metadata– Technical metadata– Preservation metadata– Rights metadata
• Structural metadata
Asset / Intellectual Work
Instantiations / Manifestations
So You’ve got this tape. Now what?
• Minimal descriptive fields you need to capture– Identifier(s)
• asset level & instantiation level• On label and assigned by archive
– Source of the identifier– Title(s)
• Formal or devised– Type(s) of title(s)– Date(s)– Date type(s)– Description– Provenance– Location
• Room, shelf, box, file path, hard drive ID, etc.
– Generation• See slide 17
Inventorying your AV assets
Inventory: Technical Metadata
• Format• Brand• Length of tape• Duration of content• Standard (NTSC, PAL, SECAM)• How many audio tracks?• Condition notes
Familiarize yourself:
• Metadata Object Description Schema (MODS)• Public Broadcasting Metadata Dictionary (PBCore)• European Broadcasting Union Core (EBUCore)• VideoMD and AudioMD (Library of Congress)• AES Core Audio• MPEG-7• PREMIS• reVTMD• MediaInfo – tool for generating technical metadata
Outsourcing digitization: RFP elements
• Introduction– Overview of institution & project and project
timeline• Project Description– Description of collection to be migrated, noting
cultural/historical significance– Information about the physical material• Formats• Signal standards• Provenance • General condition and/or storage notes
– Summary of deliverables required
RFP: Technical Requirements
• Deliverable file formats– Preservation Master– Mezzanine File– Access/Proxy file
Access Copies
• How does your institution provide access to the material?
• Does your institution provide access via the internet?
• Answering these questions will help you determine the the access copy deliverable (h264 mp4? DVD?)
Guidelines for vendors
• Shipping and registrar• Care and handling• Environmental control• Tape storage• Equipment and maintenance• Security
Metadata Requirements• You should send descriptive metadata for each tape to the vendor
including:– Title– Creator– Format– Unique ID
• Digitization process history metadata (hardware, software used to digitize)– reVTMD
• Technical metadata about the digital files– Mediainfo XML, which can be mapped to standards like PBCore
instantiations• Preservation metadata
– PREMIS
Other migration requirements
• Identical timecode of file versions• Closed captioning– Text– Timing– Bitstream data
• Naming conventions
Quality Control
• Encoding operations in clean environment• Clean playback machines• Use barcodes instead of manual entry file
naming• Spot check every file at beginning and end,
and other points in each file• Perform checksums to ensure integrity; deliver
checksums at end of project
File Delivery
• Data format (TAR, LTFS)• Data Tape Type (hard drive, LTO)• Intellectual Control – paper manifest with
GUID, tape number and checksum• Reporting (see next slide)• Duration of time to allow for you to report
defects
Vendor Monthly Deliverables
• Tape Vault environment report• Migration floor environment report• Content digitized to date• Content digitized during that month including
number of tapes per format• Failed migration report• Narrative report• Invoice
THE QUESTION OF PLAYBACK
SAFE(R) PLAYBACK
Ensure decks are clean and in working order
Test decks with test tapes before playing archival material
Never play back tapes that show signs of damage
Listen for squealing or other unusual deck noises
If tape plays successfully, always rewind before removing from the deck
AMIA Education Committee Blog & forthcoming webinar serieshttps://amiaeducomm.wordpress.com/
AMIA Video Preservation Fact Sheetshttp://www.amianet.org/sites/all/files/fact_sheets_0.pdf
Audiovisual archives: A practical readerhttp://www.unesco.org/webworld/ramp/html/r9704e/r9704e00.htm#Contents
Archival Moving Image Materials: A Cataloging Manual (2nd edition)https://archive.org/stream/AMIM2/AMIM2_djvu.txt
Audio-Visual Artifact Atlashttp://avaa.bavc.org/artifactatlas/index.php/A/V_Artifact_Atlas
Digitizing Video for Long Term Preservation: An RFP Guidehttp://library.nyu.edu/preservation/VARRFP.pdf
Image Permanence Institute Media Storage Quick Referencehttps://www.imagepermanenceinstitute.org/webfm_send/301
Preservation Self-Assessment Program: Audiovisual Mediahttp://psap.library.illinois.edu/format-id-guide/audiotape#audio2inOR
Texas Commission on the Arts Videotape Identification and Assessment Guidehttp://www.arts.texas.gov/wp-content/uploads/2012/04/video.pdf
Video Preservation Websitehttp://videopreservation.conservation-us.org/index.html
WITNESS. Activists Guide to Archiving Video.http://archiveguide.witness.org/
Questions?
Contact:
Casey DavisProject Manager, American Archive at WGBH
Rebecca FraimowNational Digital Stewardship Resident at
