Sets the speech pitch on a designated speech channel.
SDK
- macOS 10.0+
Framework
- Application
Services
Declaration
func SetSpeechPitch(_ chan: SpeechParameters
chanThe speech channel whose pitch you wish to set.
pitchThe new pitch for the speech channel, expressed as a fixed-point frequency value.
Return Value
A result code. See Result Codes.
Discussion
The Set function
changes the current speech pitch on the speech channel specified
by the chan parameter
to the pitch specified by the pitch parameter.
Typical voice frequencies range from around 90 hertz for a low-pitched
male voice to perhaps 300 hertz for a high-pitched child’s voice.
These frequencies correspond to approximate pitch values in the
ranges of 30.000 to 40.000 and 55.000 to 65.000, respectively. Although
fixed-point values allow you to specify a wide range of pitches,
not all synthesizers will support the full range of pitches. If
your application specifies a pitch that a synthesizer cannot handle, it
may adjust the pitch to fit within an acceptable range.