The VoipMediaEngine..::.DtmfGenerator type exposes the following members.
The CreateDtmfGenerator API procedure is used to create a DTMF generator. Once application software creates a DTMF generator, the DTMF generator can be turned on to generate audio sample blocks containing encoded DTMF tone data. It can also be turned off to terminate the generation of DTMF tone data.
Each sample block generated will contain 20Ms worth of PCM data using a sampling rate of 8kHz (this is equivalent to 160 - 16 bit PCM samples per block). Applications usually pass the DTMF generated sample blocks to the Media Engine's "transmit IVR Phone Line interface".
Before your application terminates, you must call the DestroyDtmfGenerator()()() API procedure to destroy the DTMF generator and to regain its resources.
The DestroyDtmfGenerator API procedure is used to destroy a previously created DTMF generator and reclaim all resources associated with the generator.
The Object's finalizer.(Overrides Object..::.Finalize()()().)
The SetDtmfGeneratorAmplitude API procedure is used to set the amplitude (volume) of generated DTMF data blocks. For most cases, application software can allow the DTMF generator to use its default amplitude.
The StartDtmfGeneratorTone API procedure is used to start the generation of DTMF sample blocks for a specific DTMF tone. The DTMF generator will call the user supplied call back procedure (that was specified by the CallbackProc parameter of the CreateDtmfGenerator(VoipMediaEngine, VoipMediaEngine..::.DTMF_GENERATOR_CALLBACK_PROC, Object) API procedure) when DTMF generator sample blocks are ready.
Once the application receives DTMF generated sample blocks, it can process them as required by the application.
To stop the generation of DTMF sample blocks at any time, call the StopDtmfGeneratorTone()()() API procedure.
The StopDtmfGeneratorTone API procedure is used to stop DTMF tone generation.
The WaitForDtmfGeneratorToneCompletion API procedure can be used to wait until a DTMF generator fully completes generating all DTMF tone data for a specified duration. For additional information, see the remarks section below.