Fixity

A comprehensive plan to manage the image library is paramount, especially as a collection grows. Regular operation of external drives keeps them functional, and regular quality checks of files are also necessary. Fixity is the ability of the image to remain intact and stable, and the process of verifying the integrity of a digital file is called fixity checking. In computer language, this is done using an assigned mathematical file called a checksum. Some video editing software provides fixity checking - consult the instructions or help community for more information.

Digital defects occur when data is migrated, transformed or compressed, resulting in loss of original data. Trusted repositories provide scheduled fixity checking to detect any digital loss before visual or audio loss is discernable. For local storage, the simplest fixity check is to open and view or listen to the files.

Files that have digital decay will be corrupted or inaccessible; occasionally pixilation or other defects can be seen in damaged files. This is why the extra copies stored in different geographic locations (local or cloud) provides backup and stability.

AVPreserve provides a suite of open source tools, including Fixity for stored files fixity check.