Structural Metadata: Previews & Ordering

Owned by Alexis Rombaut
Last updated: Oct 11, 2024
2 min read

  • The field ChildOrder has been introduced in version 23.3

  • Automatic assignment of PreviewRecordId to the first child by default is from version 23.3

  • Delete handling added from version 24.4

Introduction

By automatically filling out certain fields the system facilitates ingesting a tree for example a newspaper.

Ordering

By default when ingesting a tree each child is assigned the field Structural.ChildOrder depending on its position in the METS describing the record tree. The value starts at 1 and increases by 1 for each child.

Preview Record ID

Default

A parent record will default to the field PreviewRecordId to its first child. This first child will have its PreviewRecordId refer to its first child. This continues until it reaches the bottom of the Record Tree which is typically

  • An access representation containing a renderable preview such as a JPG image or MP4 video

  • A flat data file with its own browse JPG image or MP4 video

The PreviewRecordId can be changed later on, but by default, an ingested tree will always show the previews of its first child for each level.

Effects

Filling out the PreviewRecordId on a record has the following two effects

  1. All preview paths PathToKeyframe PathToKeyframeThumb PathToKeyframeThumb will refer to the access representation or browse by recursively resolving the PreviewRecordId

  2. The BrowseStatus will have the browse status of the actual representation or browse by recursively resolving the PreviewRecordId

When creating the SIP record tree, the PreviewRecordId is filled out before the physical preview is available. When the physical preview is available all parent records linked with the access representation via PreviewRecordId are automatically reindexed.

Delete handling 24.4+

When a record is logically deleted and it is used as a preview record, such as is the case in the record trees, then all referrers to this object will be updated with a new preview record ID. The new preview record ID is determined as follows:

  • Select the first sibling with Administrative.BrowseStatus=completed

  • If absent, select the first sibling with Administrative.BrowseStatus=in_progress

  • The siblings are sorted by the metadata field Internal.OffsetInDatabase ascending

If the new preview record ID cannot be determined, the old preview record ID will be cleared on all referring records.

Â