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MARC PROPOSAL NO. 2020-05

DATE: May 29, 2020
REVISED:

NAME: Renaming Field 345 and Defining New Subfields for Aspect Ratio in the MARC 21 Bibliographic Format

SOURCE: Network Development and MARC Standards Office (NDMSO), Library of Congress

SUMMARY:This paper proposes renaming field 345 from "Projection Characteristics of Moving Image" to "Moving Image Characteristics" and adding new repeatable subfields to record the aspect ratio.

KEYWORDS: Field 345 (BD); Projection Characteristics of Moving Image (BD); Moving Image Characteristics (BD); Aspect Ratio (BD)

RELATED: 2020-DP04, 2017-05

STATUS/COMMENTS:
05/29/20 – Made available to the MARC community for discussion.


Proposal No. 2020-05: Renaming Field 345 and Defining New Subfields for Aspect Ratio

1. BACKGROUND

A broader version of this proposal was originally presented at the January 2020 MAC meeting as MARC Discussion Paper No. 2020-DP04. At that time, there was agreement that the proposed solution met the need, along with broad support for the proposed renaming and redefinition of field 345, which parallels other field names in the MARC 3XX block. This proposal narrows the focus of changes to field 345 to the addition of subfields to store aspect ratio information, along with renaming the field to match naming conventions in the 34X block.

Field 345 is currently defined in the Bibliographic format as follows:

Field Definition and Scope:
Technical specifications relating to the projection of a moving image resource.
Multiple values from the same source vocabulary may be recorded in the same field in separate occurrences of subfield $a (Presentation format). Terms from different source vocabularies are recorded in separate occurrences of the field.

In MARC Proposal No. 2017-05, a subfield to record color content was added to field 340 on the basis that RDA defined color content as a separate element and provided a controlled vocabulary to use.

Similarly, RDA 7.19 defines Aspect Ratio. The instructions for recording both the numerical aspect ratio (e.g. 16:9, 4:3) and the aspect ratio designation (e.g. full screen, wide screen) are included, along with a vocabulary list to use for aspect ratio designation. These terms can be used to assign URIs and facilitate data exchange in a linked data environment.

Information recorded in aspect ratio is applicable to both moving images and videos. After an initial consideration to place this information in tag 346, it was decided to modify the name and definition of field 345 to align the field’s name and function with other MARC fields in the 34X block.

2. DISCUSSION

The OLAC Best Practices for Cataloging DVD/Blu-ray – Version 1.1 states that aspect ratio information can be recorded in multiple fields including 250 (Edition Statement) and 500 (General note). In addition, the current MARC-to-BIBFRAME conversion uses data in field 007/04 (Motion picture presentation format) to generate aspect ratio designators.

To facilitate consolidation of the multiple places that this information can be recorded, we propose creating discrete subfields for each element -- $c for "Aspect ratio value" and $d for "Aspect ratio designator".

3. PROPOSED CHANGES

Make the following changes to field 345 (Projection Charcteristics of Moving Image) of the MARC 21 Bibliographic Format:

3.1. Rename the Field

Rename the MARC field 345 to match the naming conventions of the other “… Characteristics” fields in the 34X block.

Rename as:
345 – Moving Image Characteristics (R)

3.2. Revise the Field Definition and Scope

Revise the Field Definition and Scope to read:

Field Definition and Scope:
Technical Specifications relating to the projection of a moving image resource.
Multiple values from the same source vocabulary may be recorded in the same field in separate occurrences of subfield $a (Presentation format) within separate subfield occurrences. Terms from different source vocabularies are recorded in separate occurrences of the field.

3.3. Add New Subfields

Add the following new subfields to field 345:

$c – Aspect ratio value (R)
A numerical ratio of the width to the height of a moving image.

$d – Aspect ratio designator (R)
A general description of the ratio of the width to the height of a moving image.

4. EXAMPLES


345 ## $c 16:9 $d wide screen

345 ## $d full screen $0 http://id.loc.gov/vocabulary/maspect/full

345 ## $c 16:9 $d letterboxed $d mixed aspect ratio
       [If URIs are included, the above example could be represented as follows:]
345 ## $c 16:9 $0 [URI for numerical aspect ratio] $2 [source]
345 ## $d letterboxed $0 http://id.loc.gov/vocabulary/maspect/letbox.html
345 ## $d mixed aspect ratio $0 http://rdaregistry.info/termList/AspectRatio/1003 $2 rdaar

5. BIBFRAME DISCUSSION

BIBFRAME Work or Instance: bf:aspectRatio (property), bf:AspectRatio (class), accommodating either a designation of the aspect ratio designation as a URI from a list or as a literal. The current MARC-to-BIBFRAME data conversion generates aspect ratio triples from field 007/04 (motion picture).

Storing this information in tag 345 will also facilitate data conversion between MARC and BIBFRAME as the standard identifier or URI of the Aspect ratio designator can be retained along with the term’s label. Placing the numeric Aspect ratio value in a separate subfield allows it to be converted to an rdf:value while the Aspect ratio designator will create an rdfs:label.

6. SUMMARY OF PROPOSED CHANGES

In field 345 (Projection Characteristics of Moving Image) of the MARC 21 Bibliographic Format, make the following changes:

6.1. Rename the field Moving Image Characteristics (R)

6.2. Revise the Field Definition and Scope to read:

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.

6.3. Add the following new subfields:

$c - Aspect ratio value (R)
$d - Aspect ratio designator (R)


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