Upload
To send data from a local computer system to a remote one. The inverse of upload is “download.”
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.
Offload
To copy media from a camera or memory card to a storage device connected to a computer.
Integrity
The quality of being whole, unaltered, and uncorrupted. A file that is not intact may not be usable or may have decreased informational and evidential value. Videos files can lose their integrity if they are accidentally mishandled, deliberately tampered with, or if data corruption occurs in transfer or storage due to hardware or software malfunction.
The best way to ensure integrity is to establish a system to check file fixity regularly (e.g. by computing hashes and checking them against a registry of previously computed hashes) and to restore any corrupted files from an intact copy.
Chain of Custody
Chronological documentation that shows who has held or controlled a video file from the moment it was created. The ability to show an unbroken chain of custody is one important indicator of the authenticity of a video, and therefore a factor in using video as evidence.
Hash Value
The string of alphanumeric characters that results from running a hash function algorithm on data or a file. The hash value of a file will always remain the same as long as the file is unchanged, so it can be used to identify altered, corrupted, and duplicated files.
