Changing the Volume of Waveform Audio Playback (Windows Embedded CE 6.0)
1/6/2010
The following table shows the Windows Embedded CE functions that query and set the volume level of waveform audio output devices.
Function | Description |
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Returns the current volume level of the specified waveform audio output device. |
|
Sets the volume level of the specified waveform audio output device. |
Volume is specified in a DWORD value. In a stereo audio format, the upper 16 bits specify the relative volume of the right channel, and the lower 16 bits specify the relative volume of the left channel. For devices that do not support separate volume control for the different channels, Windows Embedded CE uses the lower 16 bits to specify the volume level and ignores the upper 16 bits.
Windows Embedded CE uses volume ranges from 0x0 (silence) through 0xFFFF (maximum volume) and interprets these ranges logarithmically. The perceived volume increase is the same when increasing the volume level from 0x5000 through 0x6000 as when increasing the volume level from 0x4000 through 0x5000.