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

Movie AtomsReference MoviesFlagsA 32-bit integer that is currently always 0.Component descriptionA component description record. For details, see “Component Description Record” (page 126).Minimum versionAn unsigned 32-bit integer containing the minimum required version of the specified component.Component Description RecordDescribes a class of components by their attributes. Fields that are set to 0 are treated as “don’t care.”struct ComponentDescription {OSTypeOSTypeOSTypeunsigned longunsigned longcomponentType;componentSubType;componentManufacturer;componentFlags;componentFlagsMask;};componentTypeA four-character code that identifies the type of component.componentSubTypeA four-character code that identifies the subtype of the component. For example, the subtype of animage compressor component indicates the compression algorithm employed by the compressor. Avalue of 0 matches any subtype.componentManufacturerA four-character code that identifies the manufacturer of the component. Components provided by Applehave a manufacturer value of 'appl'. A value of 0 matches any manufacturer.componentFlagsA 32-bit field that contains flags describing required component capabilities. The high-order 8 bits shouldbe set to 0. The low-order 24 bits are specific to each component type. These flags can be used to indicatethe presence of features or capabilities in a given component.componentFlagsMaskA 32-bit field that indicates which flags in the componentFlags field are relevant to this operation. Foreach flag in the componentFlags field that is to be considered as a search criterion, set the correspondingbit in this field to 1. To ignore a flag, set the bit to 0.2012-08-14 | © 2004, 2012 Apple Inc. All Rights Reserved.126