Working with Meta Information:  XMP, IPTC

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What is Metadata?


Metadata is data that describes the characteristics or properties of a document. It can be distinguished from the main contents of a document. For example, for a word processing document, the contents include the actual text data and formatting information, while the metadata might include such properties as author, modification date, or copyright status. There can be gray areas where the same information could be treated as content or metadata, depending on the work flow. In general, however, metadata should have value on its own without regard for the content. For example, a list of all fonts used in a document could be useful metadata, while information about the specific font used for a specific paragraph on a page would be logically treated as content.


Metadata allows users and applications to work more effectively with documents and files, and metadata can greatly increase the utility of managed assets in collaborative production work flows. For example, an image file might contain metadata such as its working title, description, thumbnail image, and intellectual property rights data. Accessing the metadata makes it easier to perform such tasks as associating images with file names, locating image captions, or determining copyright clearance to use an image. Importantly, applications can do many useful things with metadata in files, even if they are not able to understand the native file format of the document itself.


File systems have typically provided metadata such as file modification dates and sizes. Other metadata can be provided by other applications, or by users. Metadata might or might not be stored as part of the file it is associated with.


What is XMP?


In order for multiple applications to be able to work effectively with metadata, there must be a common standard that they understand. XMP—the Extensible Metadata Platform—is designed to provide such a standard.  Designed by Adobe, the developer of Photoshop™, XMP standardizes the definition, creation, and processing of metadata by providing the following:


● A data model: A useful and flexible way of describing metadata in documents

● A storage model: The implementation of the data model

Packets: a means of packaging the data in files

Schemas: Predefined sets of metadata property definitions that are relevant for a wide range of applications, including all of Adobe’s editing and publishing products, as well as for applications from a wide variety of vendors. XMP also provides guidelines for the extension and addition of schemas.


What XMP Does Not Cover


Applications can support XMP by providing the ability to preserve and generate XMP metadata, giving users access to the metadata, and by supporting extension capabilities. A number of related areas, however, are outside the scope of XMP itself, and are under the control of the applications and tools that support XMP metadata. These areas include the following:


● The specific metadata set by each application

● The operation of media management systems

● The user interface to metadata.

● The definition of schemas beyond those defined by XMP

● Validity and consistency checking on metadata properties

● The requirement that users set or edit metadata


While the XMP specification sometimes makes recommendations in these areas, the XMP schemas and guidelines presented in the specification cannot guarantee the integrity of metadata or metadata flow. This integrity must be accomplished and maintained by a specific set of applications and tools.


In other words, XMP offers a universal storage structure, but it does not offer a means to access this information. This is left to the XMP-supported application, and it is exactly where IDimager steps in.


_img11 IDimager continues where XMP stops...


With IDimager you get:


A predefined set of the most common used XMP schemas
A way to use XMP embedded
A user interface to access the XMP data
A way to extend XMP and define your own schemas
Validity checking on meta properties
The requirement that users set or edit metadata


This makes IDimager the first non-Adobe™ product that fully supports XMP.  With IDimager you can read, write, and extend XMP schemas.