Carbon


Channel Initialization Constants

Header: Sound.h

enum {
    initChanLeft = 2,
    initChanRight = 3,
    initNoInterp = 4,
    initNoDrop = 8,
    initMono = 128,
    initStereo = 192,
    initMACE3 = 768,
    initMACE6 = 1024,
    initPanMask = 3,
    initSRateMask = 48,
    initStereoMask = 192,
    initCompMask = 65280
};

Constant descriptions

initChanLeft

Play sounds through the left channel of the Macintosh audio jack.

initChanRight

Play sounds through the right channel of the Macintosh audio jack.

initNoInterp

Do not use linear interpolation to smooth a sound played back at a different sample rate from the sound’s recorded sample rate. Using the initNoInterp initialization parameter decreases the CPU load for this channel. Sounds most affected by the absence of linear interpolation are sinusoidal sounds. Sounds least affected are noisy sound effects like explosions and screams.

initNoDrop

Do not use drop-sample conversion to fake sample rate conversion. Using the initNoDrop initialization parameter increases the CPU load for the channel but results in a smoother sound.

initMono

Play the same sound through both channels of the Macintosh audio jack and the internal speaker. This is the default channel mode.

initStereo

Play stereo sounds through both channels of the Macintosh audio jack and the internal speaker. Some machines cannot play stereo sounds.

initMACE3

Assume that the sounds to be played through the channel are MACE 3:1 compressed. The SndNewChannel function uses this information to help determine whether it can allocate a new sound channel. A noncompressed sound plays normally, even through a channel that has been initialized for MACE.

initMACE6

Assume that the sounds to be played through the channel are MACE 6:1 compressed. The SndNewChannel function uses this information to help determine whether it can allocate a new sound channel. A noncompressed sound plays normally, even through a channel that has been initialized for MACE.

initPanMask

Mask for right/left pan values.

initSRateMask

Mask for sample rate values.

initStereoMask

Mask for mono/stereo values.

initCompMask

Mask for compression IDs.

Use these constants to specify initialization parameters for a sound channel. You need to specify initialization parameters when you call SndNewChannel.


© 2000 Apple Computer, Inc. (Last Updated 6/30/2000)