Metadata
What is metadata?
Metadata is Info that relates to or is superior to other data. There are different standards for metadata. These include, for example: XMP , Exif and IPTC .
Different uses of the term “metadata”
Metadata is actually Info that is stored within a file (image) as its description. This allows, among other things, Info such as information about the photographer, time of recording, location and copyright of the image to be saved.
The users of a Digital Asset Management system refer to the Info that they write to the database about an image, for example, as metadata. This data serves as a description of the asset (e.g. image, PDF, document), e.g. title, name, keywords, categories, geodata, etc.
Application examples
Meta info is often used with digital images. In this way, for example, the photographer of the image can be saved directly in the meta info .
Another use case could be the direct transfer of meta info into an image database . This means that the meta info is read out when the image is uploaded (metadata mapping) and stored in the database. This eliminates the need for manual entry.
Metadata can be embedded into a resource (e.g. HTML tags in a web page or metadata tags in digital images) or it can be collected separately. This is the case, for example, if the objects described are non-digital resources. In principle, the data can be kept separate for use in different applications.
In the context of databases, metadata has become established as machine-readable descriptions of resources. Different formats and standards are used for different resources. The following api provide an overview of the use of metadata, particularly in the area of cultural heritage.
Classes and schemas of metadata
There are basically three classes of metadata: technical, descriptive and administrative metadata. Nevertheless, a distinction is also made between the requirements for the application and a distinction is made between capture format, storage format and exchange format.