I have been meaning to put together a list of image metadata terms and their definitions. I have found this list already created by the Metadata Working Group. So, I took it and published it here. Sometimes it’s easier to read a list in bullet form. I always try to define the terms before I use them and so, I believe this list is very helpful as a reference point.
Image metadata terms definition
- Dublin Core – The Dublin Core is a metadata element set. It includes all DCMI terms (that is, refinements, encoding schemes, and controlled vocabulary terms) intended to facilitate discovery of resources.
- EXIF “Exchangeable image file format” – standard for image file formats introduced by Japan Electronics and Information Technology industries Association (JEITA).
The EXIF standard has been created by the Japan Electronics and Information Technology industries Association (JEITA1). In particular, the Exif image interchange format defines a set of TIFF tags that describe photographic images, and is widely used by digital cameras. Exif metadata can be found in TIFF, JPEG, and PSD files.
DCF – Design rule for Camera File system. As digital still cameras (DSC) have come to enjoy wide popularity, there is a growing need for direct exchange of images between cameras and other equipment, allowing pictures taken on one camera to be viewed on another, or to be output to a printer. The DCF specification is aimed at the creation of a user environment in which consumers can combine products more freely and exchange media readily.
To this end it specifies rules for recording, reading and handling image files and other related files
used on DSC or other equipment. Amongst others, DCF defines a subset of Exif where some
properties are optional in Exif but required in DCF.
- IPTC “International Press Telecommunications Council” – creator and maintainer of metadata standards.
IPTC, based in London, UK, is a consortium of the world’s major news agencies, news publishers and
news industry vendors. It develops and maintains technical standards for improved news exchange
that are used by virtually every major news organization in the world.
In 1979, the first IPTC standard was text-only and defined to protect the interest of the
- IPTC-IIM “Information Interchange Model” – IPTC multimedia metadata standard.
Later, in 1991, a new standard, the “Information Interchange Model” (IIM), was created. It’s an envelope format for transmitting news text documents and photos and defining the so-called “IPTC headers” in many photo files, inserted by Adobe Photoshop and similar software.
After Adobe had introduced XMP in 2001, the IPTC Core standard has adopted XMP as the successor
to the IIM-based “IPTC header” used to describe millions of professional digital images.
- IPTC Core “IPTC Core” – IPTC photo metadata standard based on XMP
- IPTC Extension “IPTC Extension” – IPTC photo metadata standard based on XMP
- JPEG – The JPEG file format, widely used in image and photography workflows
- MWG “Metadata Working Group” – Industry consortium responsible for this document
- PSD – The native Adobe Photoshop file format
- RDF – The “Resource Description Framework (RDF)”, described by the W3C as a “framework for representing information in the Web”, has become a general model for representing metadata
- TIFF – The “Tagged Image File Format (TIFF)” is a file format to store images as well as photography.
- Unicode – Unicode is an industry standard to consistently represent characters and text within modern software and hardware systems
- UTF-8 – UTF-8 is a byte-oriented encoding form of Unicode
- XMP “Extensible Metadata Platform” – multimedia metadata standard introduced by Adobe.
XMP is a labeling technology that allows you to embed metadata into the file itself. With XMP, desktop applications and back-end publishing systems gain a common method for capturing, sharing, and leveraging this valuable metadata – opening the door for more efficient job processing, workflow automation, and rights management, among many other possibilities. XMP standardizes the definition, creation and processing of extensible metadata.
XMP defines a metadata model that can be used with any defined set of metadata items. XMP also defines particular schemas for basic properties useful for recording the history of a resource as it passes through multiple processing steps, from being photographed, scanned, or authored as text, through photo editing steps (such as cropping or color adjustment), to assembly into a final image.
XMP allows each software program or device along the way to add its own information to a digital
resource, which can then be retained in the final digital file.
XMP is serialized in XML and stored using a subset of the W3C Resource Description Framework
(RDF). Therefore, customers can easily define their own custom properties and namespaces to
embed arbitrary information into the file.