Archive Guide Glossary

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There are currently 5 names in this directory beginning with the letter D.
Data Dictionary

A document that explicitly describes metadata structure and rules so that all catalogers input metadata in a catalog consistently. A data dictionary may also specify your controlled vocabularies. Data dictionaries do not contain actual metadata, only the instructions needed to create your metadata.

Metadata

Any information about a video: from technical information embedded in the file that allows the video to function, such as format and duration, to descriptive information about the content to help you understand or find it--such as keywords, security restrictions, geographic locations, and so on. Metadata is critical to any future use, and is important throughout the archiving process. Despite what is sometimes said, images almost never speak for themselves. They require context and description to make sense, to corroborate their factuality, and to be accessible beyond one person’s memory or desktop. Metadata can be automatically generated and embedded in the file, such as with technical metadata, or it can be manually recorded on an external medium, such as with descriptions, security flags, and keywords in a database. Metadata capture sometimes needs to be manually enabled on your device, such as with GPS or location services.

Controlled Vocabulary

A predefined list of terms used to ensure consistency in cataloging. Since there is usually more than one way to describe or refer to a concept, choosing one term eliminates guesswork and circumvents the normal ambiguities of language (and spelling). Imagine searching for “Doctors” only to later learn that some records use the term “Physicians”. Consistent vocabularies increase the findability of records.

Data Model

A description of the way that data is structured in a database. It can define what types of things the data describe, what types of data are included in the descriptions, and how different types of things relate to each other.


Derivative

A copy of a video generated from a master that is usually in a different format and of lower quality than the master. Derivatives can be made for various uses, such as web upload or DVD.

Master

The earliest generation or highest-quality output of a video from which duplicates are made.

Digital Video

An audiovisual signal that is represented in discrete bits, as opposed to a continuous analog signal. Analog video, such as Hi8 or VHS, is obsolete; all video cameras available today record digital video. Digital video can be tape-based (e.g. miniDV, HDV) or file-based (e.g. .mov, .avi). In this guide, we focus on file-based digital video, as tape-based digital video is mostly obsolete.

Obsolescence

The process of becoming out-of-date and unsupported by available technology. Video cameras, video formats, storage media and storage devices, can all become obsolete over time. The obsolete technology is functional but is unusable because the other technologies they depend on no longer support them. An old video camera, for example, may not be able to plug into new computers, or an old video format might not be playable on new desktop video players.

Download

To receive data from a remote computer system and save it in a local computer system. The inverse of download is "upload."

Upload

To send data from a local computer system to a remote one. The inverse of upload is "download."

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