Inside Macintosh: Sound

Legacy Document

Important: Sound Input Manager is deprecated as of Mac OS X v10.5. For new audio development in Mac OS X, use Core Audio. See the Audio page in the ADC Reference Library.

Compression Information Records

When the Sound Manager calls your SoundComponentGetInfo routine with the siCompressionFactor selector, you need to return a pointer to a compression information record, which is defined by the CompressionInfo data type.



 
typedef struct {

    long                recordSize;

    OSType              format;

    short               compressionID;

    short               samplesPerPacket;

    short               bytesPerPacket;

    short               bytesPerFrame;

    short               bytesPerSample;

    short               futureUse1;

} CompressionInfo, *CompressionInfoPtr, **CompressionInfoHandle;

recordSize

The size of this compression information record.

format

The compression format.

compressionID

The compression ID.

samplesPerPacket

The number of samples in each packet.

bytesPerPacket

The number of bytes in each packet.

bytesPerFrame

The number of bytes in each frame.

bytesPerSample

The number of bytes in each sample.

futureUse1

Reserved for use by Apple Computer, Inc. You should set this field to 0.

Inside Macintosh: Sound

Legacy Document

Important: Sound Input Manager is deprecated as of Mac OS X v10.5. For new audio development in Mac OS X, use Core Audio. See the Audio page in the ADC Reference Library.