SPDUI_AudioProperties (SAPI 5.3)

Speech API 5.3
Microsoft Speech API 5.3

SPDUI_AudioProperties (C/C++)

SpeechAudioProperties (Automation)

SPDUI_AudioProperties defines the string for displaying an audio object's properties user interface (UI).

#define SPDUI_AudioProperties        L"AudioProperties"

When to Implement

An application can modify the object's implementation-specific properties for a custom audio object. For example, the SAPI implementation of the multimedia audio object has a UI so that the user can select the multimedia device line (e.g., microphone input, line input, etc.).

A custom audio object that performed noise reduction on the input stream could have a UI for selecting the audio input object to read data from initially. It could also display a UI that allows the user to adjust how much noise reduction is performed.

Speech properties in Control Panel allows the user to select the default audio input and output objects. Click Properties to directly access each audio object's properties UI using SPDUI_AudioProperties. If the audio object does not support the Properties UI (see ISpTokenUI::IsUISupported), Properties will be unavailable.


The following code snippet illustrates the use of ISpTokenUI::IsUISupported using SPDUI_AudioProperties.

// Declare local identifiers:
HRESULT                    hr = S_OK;
CComPtr<ISpObjectToken>    cpObjectToken;
CComPtr<ISpTokenUI>        cpTokenUI;
BOOL                       fSupported;

// Get the default input audio object token.
hr = SpGetDefaultTokenFromCategoryId(SPCAT_AUDIOIN, &cpObjectToken;);

if (SUCCEEDED(hr))
   // Get the object token's UI.
   hr = cpObjectToken->QueryInterface(&cpTokenUI;);

// Check if the default audio input object has UI for Properties.
hr = cpTokenUI->IsUISupported(SPDUI_AudioProperties, NULL, NULL, NULL, &fSupported;);

if (SUCCEEDED(hr))
   // If fSupported = TRUE, then default audio
   // input object has UI for Properties.