Structs



AudioHardwareIOProcStreamUsage


This structure describes which streams a given AudioDeviceIOProc will use. It is used in conjunction with kAudioDevicePropertyIOProcStreamUsage.
struct  AudioHardwareIOProcStreamUsage {
    void*   mIOProc;
    UInt32  mNumberStreams;
    UInt32  mStreamIsOn[kVariableLengthArray];
} ;
Field Descriptions
mIOProc
The IOProc whose stream usage is being specified.
mNumberStreams
The number of streams being specified.
mStreamIsOn
An array of UInt32's whose length is specified by mNumberStreams. Each element of the array corresponds to a stream. A value of 0 means the stream is not to be enabled. Any other value means the stream is to be used.

AudioObjectPropertyAddress


An AudioObjectPropertyAddress collects the three parts that identify a specific property together in a struct for easy transmission.
struct  AudioObjectPropertyAddress {
    AudioObjectPropertySelector mSelector;
    AudioObjectPropertyScope    mScope;
    AudioObjectPropertyElement  mElement;
} ;
Field Descriptions
mSelector
The AudioObjectPropertySelector for the property.
mScope
The AudioObjectPropertyScope for the property.
mElement
The AudioObjectPropertyElement for the property.

AudioStreamRangedDescription


This structure allows a specific sample rate range to be associated with an AudioStreamBasicDescription that specifies it's sample rate as kAudioStreamAnyRate.
struct  AudioStreamRangedDescription {
    AudioStreamBasicDescription     mFormat;
    AudioValueRange                 mSampleRateRange;
} ;
Discussion

Note that this structure is only used to desicribe the the available formats for a stream. It is not used for the current format.

Field Descriptions
mFormat
The AudioStreamBasicDescription that describes the format of the stream. Note that the mSampleRate field of the structure will be the same as the the values in mSampleRateRange when only a single sample rate is supported. It will be kAudioStreamAnyRate when there is a range with more elements.
mSampleRateRange
The AudioValueRange that describes the minimum and maximum sample rate for the stream. If the mSampleRate field of mFormat is kAudioStreamAnyRate the format supports the range of sample rates described by this structure. Otherwise, the minimum will be the same as the maximum which will be the same as the mSampleRate field of mFormat.

(Last Updated 12/13/2004)