Controlling metadata field availability in Assets Server

Metadata fields can be made available to all assets within Assets Server or can be restricted to specific assets only. This is done by making the metadata field part of a particular level within a hierarchical structure.

This structure is referred to as the 'Asset Type Base' structure and is shown below.

How to read the structure

The structure works from top to bottom, meaning that at any level in the structure all metadata fields of that level are available as well as all metadata fields of all levels above it but not the metadata fields of the levels that follow.

Example: ZIP files are part of the 'GeneralFields' section, meaning that a ZIP file will have access to all metadata fields that are defined for 'GeneralFields' as well as all metadata fields defined in the levels above it (from 'RootSystemFields' to 'DimensionFields'). Metadata fields that are defined for the levels below 'GeneralFields' such as in 'ImageFields' or 'DocumentFields' are not available for ZIP files.

When looking at the structure closely you will see that the top half (up to and including 'GeneralFields') contains generic sections that together hold metadata fields that all assets should have access to.

Below 'GeneralFields' the sections are very specific to file types: the lower you get in the structure, the more specific the definitions become.

This makes it possible to make a particular metadata field available to a specific file type.

Example: To only make a metadata field available to audio files, assign it to 'AudioFields'. Because of its place in the hierarchy, an audio file will also have access to all metadata fields that are defined in all levels above it in the structure (from 'RootSystemFields' to 'ImageAndVideoFields') but any fields that are defined in 'VideoFields' and 'FlashFields' are not accessible for audio files.

The structure and its fields

Below follows some examples of the fields that each level of the structure holds.

Note: To find all configured fields, search for the section in the full_assetinfo.xml file. The location of this file is: <Assets Server location>/Elvis Hot Data/elvis-data/assetInfo

RootSystemFields

This holds metadata fields that are applicable to the system itself. Examples:

• File Name
• Directory
• Extension

VersionFields

This holds metadata fields that are to do with working with different file versions. Examples:

• Version comment
• Version backup created by
• Version ID

CommonFields

This holds metadata fields that are commonly used by all assets. Examples:

• Tags
• Rating
• Status

WoodWingFields

This holds metadata fields that match those from WoodWing Studio Server. Examples:

• Publication
• Category
• Issue

SwitchFields

This holds metadata fields that match those from Enfocus Switch. Examples:

• Picked up by Switch
• Preview state
• Metadata complete

FileAssetFields

This holds metadata fields that are specific to assets. Examples:

• File created date
• File modified date
• MIME type

ReferenceFields

This holds metadata fields that are related to their origin or source. Examples:

• Original Document ID
• Document ID
• Derived from original document

DimensionFields

This holds metadata fields that are specific to the dimension of an asset. Examples:

• Size (pixels)
• Size (millimeters)
• Size (points)

GeneralFields

This holds metadata fields that are used in a general sense for an asset. Examples:

• Caption writer
• Title
• Category

CollectionFields

This holds metadata fields that are specific to Collections. It is empty by default.

ImageAndVideoFields

This holds metadata fields that are specific to images and videos. It is empty by default.

ImageFields

This holds metadata fields that are specific to images. Examples:

• Bit depth
• Color mode

ExifFields

This holds metadata fields that are specific to the exchangeable image format 'exif'. Examples:

• Camera model
• Orientation
• Compression

AudioFields

This holds metadata fields that are specific to audio files. Examples:

• Duration
• Title
• Artist

VideoFields

This holds metadata fields that are specific to videos. Examples:

• Scene
• Shot name
• Shot location

FlashFields

This holds metadata fields that are specific to Adobe Flash files. Example:

• Flash version

TextFileAssetFields

This holds metadata fields that are specific to text files and documents. Example:

• Text content

TextFields

This holds metadata fields that are specific to text files. It is empty by default.

DocumentFields

This holds metadata fields that are specific to documents. Examples:

• Document template
• Number of pages
• Character count

PdfFields

This holds metadata fields that are specific to PDF files. Examples:

• PDF producer
• PDF version
• Tagged PDF

Assigning a metadata field to the structure

When creating a custom metadata field, it also needs to be assigned to a level in the 'Asset Type Base' structure.

This is done by 'extending' the default Asset Type Base with a new configuration which will overrule the default configuration.

In the following example, 'CollectionFields' is extended (by using the element assetTypeBaseExt) and a custom metadata field is defined for it. As a result, the custom metadata field named 'cf_CustomCollection' will only be available to Collections.

<assetTypeBaseExt name="CollectionFields">
   <fields>	
      <field name="cf_CustomCollection" group="Test" >
	<storage storeInMetadata="true" />
	<compass index="un_tokenized" store="yes" excludeFromAll="false" />
	<data editable="true" datatype="text" />
	</field>
	</fields>
</assetTypeBaseExt>