It's a contraction of the terms "Metadata" and "Cataloging." And in case you didn't know, Metadata can be defined as information regarding the characteristics of any object, such as its name, location, importance, quality and relationship to other objects in the collection. In other words, it's structured information about resources. Cataloging is the act of adding an image to an image database.
"Metalogging" is the process of adding descriptive information about an image and storing it in such a way that it can be used as an aid in retrieving that image from a database or collection after it is "cataloged. Metalogging includes activities such as adding captions that explain what is occurring in the image, as well as determining which imagery-rich keywords and other known information (location, date & time, etc.) should be included.
Describing images didn't begin with the advent of digital imaging or digital cameras. Photographers, as well as journalists, editors, stock agencies, librarians, and other collections specialists have been writing captions for images for years. In the paper age, this information was written on the back of the print or contact sheet, or often on the mount of the 35mm slide. With digital image files there is no back of the print, as there often is no print! However, with digital images, comes the ability to store textual information alongside the image data in the form of "metadata" The Image Database portion of this site discusses ways in which you can store this information within the digital image itself through the use of the IPTC standard, and newer metadata schemas. This section of the Controlled Vocabulary site will focus on resources, suggestions and guidelines to make creating metadata easier. Use the links at the top or bottom of this page to navigate between the other pages. If you run into metadata fields which you aren't sure how to use, you might want to check out the Metadata Field Guide on the PhotoMetadata.org website. An earlier version of this information can be found on the International Press Telecommunications Council (IPTC) website, as the User's Guide to the IPTC Core.
The primary reason is to exploit the underlying technology that is used in most of the upper-end image databases. Canto Cumulus, Extensis Portfolio, FotoStation, iView Multimedia/MediaPro, iMatch, Hindsight Stockview and a number of others will create thumbnails and "export" the metadata found in the various IPTC / File Info / XMP storage "containers." Each application may differ in how this info is stored, so I highly recommend downloading the demos and "dating" each demo version before making a serious commitment to one or the other. You can find links to many of the better image database programs as well as reviews on the programs page in that section. Note that some applications which are designed for all kinds of digital objects (not just digital photos) may require initializing the application, or some extended set up routines in order to be able to extract the embedded metadata.
Once you have your metadata "embedded" (stored
inside the image header) in the file, then it travels anywhere the file goes.
upload an image with embedded IPTC information to a metadata savvy online portal
like Alamy, PhotoShelter,
even a photo sharing site like Flickr,
this information is automatically transferred
into that system. Other individuals can then search using the information in
many of those fields to locate images with the subject they are trying to find.
Be aware, however, that there are a growing number of social media and photo
sharing sites which seem to be unaware of the power of embedded metadata, and
may intentionally or inadvertantly be removing the metadata you have added
to your images. Find out more about the Controlled Vocabulary Survey
Preservation of Photo Metadata by Social Media Websites on this site, and see if the service you are using is mentioned.
There are various forms of metadata that already may exist in a digital image, as well as that which you can add or embed. EXIF data typically contains read-only information on the digital camera used to make the image, and/or the application used to save the image file last. For more details about the standard made popular by the International Press Telecommunications Council (IPTC) and Adobe, see the IPTC-NAA page. For more details about how the various Photo Metadata Schemas work together visit the Meta101 section of the Photometadata.org website.
Proceed to Captioning page >>