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

Media Data Atom TypesSound MediaSoundDescriptiondesc;// fixed compression ratio informationunsigned longunsigned longunsigned longunsigned longsamplesPerPacket;bytesPerPacket;bytesPerFrame;bytesPerSample;// optional, additional atom-based fields --// ([long size, long type, some data], repeat)};Version 2 of the sound sample description maintains the same mechanism for the addition of extensions. Inthe sound sample description v2 structure, the sizeOfStructOnly field value provides the offset to theextensions.siSlopeAndIntercept AtomNote The siSlopeAndIntercept atom is deprecated in the QuickTime file format. The informationthat follows is intended to document existing content containing this atom and should not be usedfor new development.The siSlopeAndIntercept atom contains slope, intercept, minClip, and maxClip parameters relevant toa decompressor component.At runtime, the contents of the type siSlopeAndIntercept and siDecompressorSettings atoms areprovided to the decompressor component through the standard SetInfo mechanism of the Sound Manager.struct SoundSlopeAndInterceptRecord {Float64Float64Float64Float64slope;intercept;minClip;maxClip;};typedef struct SoundSlopeAndInterceptRecord SoundSlopeAndInterceptRecord;2012-08-14 | © 2004, 2012 Apple Inc. All Rights Reserved.184