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DATE: December 21, 2021
REVISED:
NAME: Revising Field 340 to Reduce Redundancies Related to Newer Fields 34X in the MARC 21 Bibliographic Format
SOURCE: OCLC, in consultation with Music Library Association (MLA) and Online Audiovisual Catalogers (OLAC)
SUMMARY: This paper proposes revising the definition of Bibliographic field 340 (Physical Medium) subfield $f, currently defined for "Production Rate/Ratio," to be specifically for microform "Reduction Ratio Value." It further proposes a new corresponding subfield $q for "Reduction Ratio Designator." The object is to reduce redundancies and confusion about more recently defined 34X fields and their subfields that are now specifically suitable for several historical uses of field 340 subfield $f.
KEYWORDS: Aspect Ratio (BD); Digital File Characteristics (BD); Digital Graphic Representation (BD); Encoded Bitrate (BD); Encoding Format (BD); Field 340 (BD); Field 344 (BD); Field 345 (BD); Field 347 (BD); Field 352 (BD); Format of the Digital Image (BD); Moving Image Characteristics (BD); Physical Medium (BD); Playing Speed (BD); Production Rate/Ratio (BD); Projection Characteristics of Moving Image (BD); Projection Speed (BD); Reduction Ratio (BD); Sound Characteristics (BD); Subfield $b, in field 345 (BD); Subfield $b, in field 347 (BD); Subfield $c, in field 344 (BD); Subfield $c, in field 345 (BD); Subfield $f, in field 340 (BD); Subfield $f, in field 347 (BD); Subfield $q, in field 352 (BD); Transmission Speed (BD); Vocabulary Encoding Schemes (BD)
RELATED: 2016-DP10, 2016-DP22, 2020-DP03, 2020-DP04, 2020-DP14, 2021-DP04; 2021-DP08; 94-17, 2003-05, 2011-08, 2014-03, 2017-05, 2020-04, 2020-05, 2021-07, 2021-10; 2021-14; 2021-16.
STATUS/COMMENTS:
12/21/21 – Made available to the MARC community for discussion.
01/25/22 – Results of MARC Advisory Committee discussion: Approved, with the following editorial amendments:
05/17/22 – Results of MARC Steering Group review - Agreed with the MAC decision.
In MARC Discussion Paper No. 2021-DP08, "Cleaning Up Redundancies Related to Fields 34X in the MARC 21 Bibliographic Format," the case was made for reducing redundancies that had resulted from the implementation in 2011 of several new fields that allowed for the recording of specific technical characteristics: field 344 for sound, field 345 for moving images, and field 347 for digital files. In these fields, plus the existing field 352 for Digital Graphic Representation, there are subfields whose definitions needlessly overlap with the definition of legacy field 340 subfield $f. The current definition of field 340 subfield $f (Production rate/ratio) explicitly and implicitly duplicates the more specialized intentions of the newer fields and subfields. The revisions to field 340 revolve around microform resources, which are now mostly legacy records. The true beneficiaries of the changes, however, will be bibliographic records for both tangible and digital sound, moving image, and other types of resources that will now be more correctly and consistently coded in newer fields specifically intended for them.
Discussion Paper No. 2021-DP08 outlined the then-current states of each of the relevant fields 340, 344, 345, 347, and 352. Repetition of some of that information is unavoidable. The focus of this proposal, however, will be on how fields 344, 345, and 347 in particular now better accommodate certain information that need no longer be included in field 340 subfield $f.
As documented in the "Results of MARC Advisory Committee discussion" section of 2021-DP08, "There was widespread agreement, even among those with some concerns, that cleaning up the documented redundancies would reduce confusion and make for clearer MARC records."
Building upon and incorporating the feedback from that discussion, this proposal suggests clarifications to the definitions of Bibliographic field 340 and its existing subfield $f. Prompted by an idea mentioned in the discussion paper and expanded upon in the MAC comments, a new subfield $q is also being proposed for field 340 so that there will be complementary subfields for both "reduction ratio value" and "reduction ratio designator." The result will be more precise MARC coding practices, less confusion among catalogers, cleaner alignment of MARC with RDA, and improved conversion from MARC to BIBFRAME in the future.
Because elements in fields 344, 345, 347, and 352 have more recently been defined expressly for technical characteristics previously defined in much more general terms in field 340, fields 344, 345, 347, and 352 will be documented here first. The suggested changes to field 340 (described in Section 3) will follow consideration of those four fields.
Introduced in 2011, Bibliographic field 344 and its subfield $c are currently defined as follows:
344 - Sound Characteristics (R)
Field Definition and Scope
Specifications relating to the encoding of sound or the absence of sound in a resource.
Multiple values from the same source vocabulary may be recorded in the same field in separate occurrences of subfields. Terms from different source vocabularies are recorded in separate occurrences of the field.
…$c - Playing speed (R)
The speed at which an audio carrier must be operated to produce the sound intended.344 ##$a analog $2 rdatr
344 ##$c 78 rpm
The definition of field 340 subfield $f (Production rate/ratio) currently reads (with bold italic emphasis added): "Normal rate or ratio at which the information in the material must be used to be meaningful (e.g., how many revolutions per minute for recordings, the magnification for photographic reductions)." Field 344 subfield $c, the definition of which is specific to the playing speed of recorded sound, is now the preferred home for this information. In the New RDA Toolkit, the redundancy of field 340 subfield $f and field 344 subfield $c is documented in the "playing speed" MARC 21 Bibliographic Element Reference (https://access.rdatoolkit.org/en-US_ala-c0e17190-6a94-3d83-a2a3-9e55ecac1c55/d151fc1e-36b1-401e-8ed1-20817e33b3f1), which includes the following (bold italic emphasis added):
MARC 21 Bibliographic 500 ** $a [unstructured description]
MARC 21 Bibliographic 300 ** $b [structured description]
MARC 21 Bibliographic 340 ** $f [structured description]
MARC 21 Bibliographic 344 ** $c [structured description]
MARC 21 Bibliographic 007 /03 [identifier] (sound recording)
MARC 21 Bibliographic 340 ** $0 [identifier]
MARC 21 Bibliographic 344 ** $0 [identifier]
MARC 21 Bibliographic 340 ** $1 [IRI]
MARC 21 Bibliographic 344 ** $1 [IRI]
The definition of field 340 subfield $f needs to be revised to remove its past use for the playing speed of recorded sound.
Bibliographic field 345 was originally introduced in 2011 as "Projection Characteristics of Moving Image," with its application limited to literal projected motion picture film. In 2020, field 345 was renamed as "Moving Image Characteristics" and its application broadened to encompass all moving images including video, whether tangible or online. Field 345 and the subfields relevant to this discussion are currently defined as follows:
345 - Moving Image Characteristics (R)
Field Definition and Scope
Specifications relating to a moving image resource.
Multiple values from the same source vocabulary may be recorded in the same field within separate subfield occurrences. Terms from different source vocabularies are recorded in separate occurrences of the field.
…$b - Projection speed (R)
The speed at which a device must be operated to produce the moving image intended.345 ##$a Cinerama $2 rdapf
345 ##$b 24 fps$c - Aspect ratio value (R)
A numerical ratio of the width to the height of a moving image.345 ##$c 16:9 $d wide screen
$d - Aspect ratio designator (R)
A general description of the ratio of the width to the height of a moving image.345 ##$d letterboxed $d mixed aspect ratio
The most obvious duplication with field 340 subfield $f (Production rate/ratio) here is field 345 subfield $b, "Projection Speed." In the New RDA Toolkit, the redundancy of field 340 subfield $f and field 345 subfield $b is documented in the "projection speed" MARC 21 Bibliographic element reference (https://access.rdatoolkit.org/en-US_ala-bd206bf1-d3a9-3997-9f63-f4ac9604ad49/2ceb5646-f1d0-47bf-98d2-1e426cfb9fe4), which includes the following (bold italic emphasis added):
MARC 21 Bibliographic 500 ** $a [unstructured description]
MARC 21 Bibliographic 300 ** $b [structured description]
MARC 21 Bibliographic 340 ** $f [structured description]
MARC 21 Bibliographic 345 ** $b [structured description]
The revision to the definition of field 340 subfield $f that removes its past use for the playing speed of recorded sound applies equally to the projection speed of moving images.
Because the definition of field 340 subfield $f is "Production Rate/Ratio," it furthermore seems prudent to consider field 345 subfields $c and $d, both of which regard the aspect ratio of moving images, as well.
Bibliographic field 347, "Digital File Characteristics," was originally introduced in 2011. At that time, subfield $f was named "Transmission speed" and defined as "The speed at which streaming audio or video is designed to play." But subfield $f was renamed "Encoded bitrate" in 2014, corresponding to the parallel change to RDA 3.19.7, as part of the July 2013 RDA Update. Bibliographic field 347 and its subfield $f are currently defined as follows:
347 - Digital File Characteristics (R)
Field Definition and Scope
Technical specification relating to the digital encoding of text, image, audio, video, and other types of data in a resource. This information could also be recorded in field 300 (Physical Description) $b (Other physical details).
Multiple values from the same source vocabulary may be recorded in the same field in separate occurrences of subfields. Terms from different source vocabularies are recorded in separate occurrences of the field.
…$f - Encoded bitrate (R)
The speed at which streaming audio, video, etc., is designed to play.347 ##$a audio file $2 rdaft
347 ##$b MP3
347 ##$f 32 kbps
The revision to the definition of field 340 subfield $f (Production rate/ratio) that removes its past use for the playing speed of recorded sound applies equally to the encoded bitrate of streaming audio, video, or other media.
Field 347 is also defined in the MARC Holdings format, but Holdings does not define field 340, so there is no chance of similar confusion.
2.1.3.1. Relationship Between Bibliographic Field 347 Subfield $b and Field 352 Subfield $q
Raised in Discussion Paper No. 2021-DP08 was the question of redundancy between Bibliographic field 347 subfield $b (Encoding format) and Bibliographic field 352 subfield $q (Format of the digital image). In the New RDA Toolkit, the redundancy is recognized in the "encoding format" MARC 21 Bibliographic element reference (https://access.rdatoolkit.org/en-US_ala-c0a3392a-14e8-30f7-8cca-41e8c4334d44/c161de92-fe3c-433e-832d-da53fb2666b8), which includes the following (bold italic emphasis added):
MARC 21 Bibliographic 500 ** $a [unstructured description]
MARC 21 Bibliographic 538 ** $a [unstructured description]
MARC 21 Bibliographic 300 ** $b [structured description]
MARC 21 Bibliographic 347 ** $b [structured description]
MARC 21 Bibliographic 352 ** $q [structured description]
MARC 21 Bibliographic 347 ** $0 [identifier]
MARC 21 Bibliographic 347 ** $1 [IRI]
The current text of the repeatable field 347 subfield $b reads:
347 - Digital File Characteristics (R)
$b - Encoding format (R)
A schema, standard, etc., used to encode the digital content of a resource.347 ##$atext file$2rdaft
347 ##$bPDF347 ##$avideo file$2rdaft
347 ##$bBlu-Ray
Bibliographic field 352 and its subfield $q are currently defined as follows:
352 - Digital Graphic Representation (R)
Field Definition and Scope
Description of the method of referencing and the mechanism used to represent graphic information in a data set. This information consists of the type of storage technique used, the number of items in the data set, and the format in which the data is stored.
…$q - Format of the digital image (NR)
Name of the format in which the digital image is stored.352 ##$aVector : $b Point $c (13671), $b string $c (20171), $b GT-polygon composed of chains $c (13672) ; $q ARC/INFO export.
352 ##$a Raster : $b pixel $d (5,000 x $e 5,000) ; $q TIFF.
The definitions of field 352 and its subfield $q have long been understood to be limited to the digital format of cartographic data sets, whereas field 347 is much more broadly defined to include "the digital encoding of text, image, audio, video, and other types of data in a resource." In the context of the other 34X changes brought up in 2021-DP08, the overlap between these two subfields was discussed, but the general consensus was to allow both subfields to coexist as they stand.
Bibliographic field 340 and its subfield $f are currently defined as follows:
340 - Physical Medium (R)
Field Definition and Scope
Physical description information for an item that requires technical equipment for its use, and/or more granular description information of an item's material properties to facilitate access and discovery or to support collection management.
Coded physical information is contained in field 007 (Physical Description Fixed Field) and field 008 (Fixed-Length Data Elements). The field is repeated for each subfield $3 (Materials specified).
Multiple values from the same source vocabulary may be recorded in the same field in separate occurrences of subfields. Terms from different source vocabularies are recorded in separate occurrences of the field.
…$f - Production rate/ratio (R)
Normal rate or ratio at which the information in the material must be used to be meaningful (e.g., how many revolutions per minute for recordings, the magnification for photographic reductions).340 ##$3 case files $a aperture cards $b 9 x 19 cm $d microfilm $f 48x.
In 2011, MARC Proposal No. 2011-08 had suggested the possible augmentation of field 340 to identify each general carrier characteristic then found in RDA with a particular subfield of field 340. In Section 2.3 of that proposal, subfield $f was explicitly identified with RDA 3.15, "Reduction ratio." That proposal led to the addition of Bibliographic fields 344, 345, 346, and 347, as well as subfields $j, $k, $m, $n, and $o to field 340. At that time, the definition of field 340 subfield $f already accounted for reduction ratio but was not tightened up sufficiently to remove references to playing speeds that would henceforth be covered by the newly defined fields and subfields. Now we propose to finally align field 340 subfield $f with the 2011 intention and furthermore to incorporate suggestions from the 2021 discussion of 2021-DP08.
In the 2021 April 1 analysis of the 509,146,170 bibliographic records in WorldCat, field 340 was found in 7,824.583 of them (1.54% of all WorldCat records), and in turn subfield $f appeared in 27,549 of those (0.35% of all fields 340). Roughly 2,600 of those subfields $f currently contain identifiable reduction ratios, about 45 contain identifiable moving image projection speeds, and smaller numbers contain identifiable aspect ratios. Small numbers contain data that are not obviously related to any current or past definition of subfield $f and/or would require individual investigation. The remaining 24,000 to 25,000 contain sound recording playing speeds. OCLC would be able to clean up and/or convert most or all of the subfields $f in WorldCat. To provide some context, here are the corresponding WorldCat statistics on the three fields and six subfields discussed:
Revision of the definition of the existing field 340 subfield $f and the proposal for a new subfield $q take cues from such paired value and designator subfield pairs as field 345 subfields $c (Aspect ratio value) and $d (Aspect ratio designator), the RDA definition of "reduction ratio," and the definitions of field 340 subfields $n (Font size) and $p (Illustrative content). A major point of the 2021-DP08 discussion was to reduce any potential confusion over former uses of field 340 subfield $f with the more recently defined specific 34X fields and subfields. The proposed changes are described in Section 3.2.
2.1.4.1. Bibliographic Field 340 Proposed New Subfield $q
The RDA Reduction Ratio Designation (RDA 16.10.70.85) Vocabulary Encoding Scheme (https://access.rdatoolkit.org/VES/VES?externalId=en-US_rdaves_RDA_Reduction_Ratio_Designation) maintains a controlled vocabulary of the five "concepts for a numerical ratio of the size of a micro-image in relation to the original from which it was produced." When this vocabulary is used, subfield $2 is coded "rdarr".The five terms currently defined in the vocabulary are:
We propose adding a new subfield $q for "Reduction ratio designator" to field 340 (described in Section 3.3.).
In field 340 (Physical Medium) of the MARC 21 Bibliographic format:
Revise the 340 Field Definition and Scope as follows (changes are in bold italics):
340 - Physical Medium (R)
Field Definition and Scope
Physical description information for an item that requires technical equipment for its use, and/or more granular description information of an item's material properties to facilitate access and discovery or to support collection management.
Coded physical information is contained in field 007 (Physical Description Fixed Field) and field 008 (Fixed-Length Data Elements). For specifications relating to the encoding of sound or the absence of sound, prefer field 344 (Sound Characteristics). For specifications relating to moving image resources, prefer field 345 (Moving Image Characteristics). For specifications relating to the encoding of video images, prefer field 346 (Video Characteristics). For specifications relating to the digital encoding of text, image, audio, video, and other types of data, prefer field 347 (Digital File Characteristics). The field is repeated for each subfield $3 (Materials specified).
Multiple values from the same source vocabulary may be recorded in the same field in separate occurrences of subfields. Terms from different source vocabularies are recorded in separate occurrences of the field.
Rename subfield $f from "Production rate/ratio" to "Reduction ratio value" and fully revise the definition as follows:
$f – Reduction ratio value (R)
A specific indication of the size of a micro-image in relation to the original from which it was produced. Most commonly, it is expressed numerically as a reduction ratio (e.g., 16:1, 90:1) or as a magnification value (e.g., 16x, 90x). For such designations expressed in general terms, use field 340 subfield $q (Reduction ratio designation).
For the playing speed of sound resources, prefer field 344 (Sound Characteristics) subfield $c (Playing Speed). For the projection speed of moving image resources, prefer field 345 (Moving Image Characteristics) subfield $b (Projection Speed). For the aspect ratio of moving images, prefer field 345 subfield $c (Aspect ratio value) and/or $d (Aspect ratio designator). For specifications relating to the speed at which audio, video, and other types of digital data are designed to play, prefer field 347 (Digital File Characteristics) subfield $f (Encoded bitrate)340 ##$3 case files $f 48x
Define new subfield $q as follows:
$q - Reduction ratio designator (R)
A general description of the size of a micro-image in relation to the original from which it was produced, expressed in general terms (e.g., low reduction, ultra high reduction). For such designations expressed in specific numerical terms, use subfield $f (Reduction ratio value).336 ##$a text $b txt $2 rdacontent $3 case files
337 ##$a microform $b h $2 rdamedia $3 case files
338 ##$a aperture card $b ha $2 rdacarrier $3 case files
340 ##$3 case files $a aperture cards
340 ##$3 case files $b 9 x 19 cm
340 ##$3 case files $d microfilm
340 ##$3 case files $f 48x
340 ##$3 case files $q high reduction $2 rdarr
4.1. Bibliographic Field 340 Subfield $f with Numerical Reduction Ratio and Subfield $q with Reduction Ratio Designator
336 ##$a text $b txt $2 rdacontent
337 ##$a microform $b h $2 rdamedia
338 ##$a microfiche $b ha $2 rdacarrier
340 ##$a safety base $2 rdamat
340 ##$b 11 x 15 cm
340 ##$f 24:1
340 ##$j service copy $2 rdagen
340 ##$o negative $2 rdapo
340 ##$q normal reduction $2 rdarr
4.2. Bibliographic Field 340 Subfield $f with Numerical Magnification Value and Subfield $q with Reduction Ratio Designator
336 ##$a text $b txt $2 rdacontent
337 ##$a microform $b h $2 rdamedia
338 ##$a microfiche $b ha $2 rdacarrier
340 ##$a safety base $2 rdamat
340 ##$b 11 x 15 cm
340 ##$f 24x
340 ##$j service copy $2 rdagen
340 ##$o negative $2 rdapo
340 ##$q normal reduction $2 rdarr
Better definition and alignment with RDA will improve conversion from MARC to BIBFRAME since BIBFRAME is aligned with RDA.
In field 340 (Physical Medium) of the MARC 21 Bibliographic Format, make the following changes:
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