Quicktime File Format (2012-08-14).pdf

MetadataValue AtomValue AtomThe value of the metadata item is expressed as immediate data in a value atom. The value atom starts withtwo fields: a type indicator, and a locale indicator. Both the type and locale indicators are four bytes long. Theremay be multiple ‘value’ entries, using different type, country or language codes (see the Data Ordering sectionbelow for the required ordering).The Value atom structure contains the following fields:TypeA type indicator, defined in “Type Indicator” (page 139).LocaleA locale indicator, defined in “Locale Indicator” (page 139).Type IndicatorThe type indicator is formed of four bytes split between two fields. The first byte indicates the set of types fromwhich the type is drawn. The second through fourth byte forms the second field and its interpretation dependsupon the value in the first field.The indicator byte must have a value of 0, meaning the type is drawn from the well-known set of types. Allother values are reserved.If the type indicator byte is 0, the following 24 bits hold the well-known type. Please refer to the list ofWell-Known Types, in the Well-Known Types section below.Locale IndicatorThe locale indicator is formatted as a four-byte value. It is formed from two two-byte values: a country indicator,and a language indicator. In each case, the two-byte field has the possible values shown in Table 3-3 (page139).Table 3-3Value01 to 255Country and language indicatorsMeaningThis atom provides the default value of this datum for any locale not explicitly listed.The value is an index into the country or language list (the upper byte is 0).2012-08-14 | © 2004, 2012 Apple Inc. All Rights Reserved.139