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

Movie AtomsTrack AtomsRegion sizeThe region size, region boundary box, and clipping region data fields constitute a QuickDraw region.Region boundary boxThe region size, region boundary box, and clipping region data fields constitute a QuickDraw region.Clipping region dataThe region size, region boundary box, and clipping region data fields constitute a QuickDraw region.Track Matte AtomsTrack matte atoms are used to visually blend the track’s image when it is displayed.Track matte atoms have an atom type value of 'matt'.Figure 2-14 (page 68) shows the layout of track matte atoms.Figure 2-14The layout of a track matte atomBytesTrack matte atomAtom sizeType = 'matt'44Compressed matte atomAtom sizeType = 'kmat'VersionFlagsMatte imagedescription structureMatte data4413VariableVariableTrack matte atoms contain the following data elements.SizeA 32-bit integer that specifies the number of bytes in this track matte atom.TypeA 32-bit integer that identifies the atom type; this field must be set to 'matt'.2012-08-14 | © 2004, 2012 Apple Inc. All Rights Reserved.68