Images that are used within UIElements are exposed as separate Variables rather than embedding them in the element. All image Variables will be aggregated by the ImageSet folder. The UIElement shall specify an image by its name that is also the BrowseName of the image Variable. Clients can cache images so they don't have to be transferred more than once. The “ImageSetFolder is formally defined in Table 24.

Table 24 – ImageSet definition

Attribute

Value

BrowseName

ImageSet

References

NodeClass

BrowseName

TypeDefinition

DataType

ModellingRule

HasTypeDefinition

ObjectType

FolderType (defined in OPC 10000-5.)

HasComponent

Variable

<ImageIdentifier>

BaseDataVariableType

Image

MandatoryPlaceholder

The DataType of the Variable specifies the image format. OPC UA defines BMP, GIF, JPG and PNG (see OPC 10000-3).