Author: Udo Nesshoever

How do I get the soundcard's volume? How to set it ?

Answer:

1   procedure GetVolume(var volL, volR: Word);
2   var
3     hWO: HWAVEOUT;
4     waveF: TWAVEFORMATEX;
5     vol: DWORD;
6   begin
7     volL := 0;
8     volR := 0;
9     // init TWAVEFORMATEX
10    FillChar(waveF, SizeOf(waveF), 0);
11    // open WaveMapper = std output of playsound
12    waveOutOpen(@hWO, WAVE_MAPPER, @waveF, 0, 0, 0);
13    // get volume
14    waveOutGetVolume(hWO, @vol);
15    volL := vol and $FFFF;
16    volR := vol shr 16;
17    waveOutClose(hWO);
18  end;
19  
20  procedure SetVolume(const volL, volR: Word);
21  var
22    hWO: HWAVEOUT;
23    waveF: TWAVEFORMATEX;
24    vol: DWORD;
25  begin
26    // init TWAVEFORMATEX
27    FillChar(waveF, SizeOf(waveF), 0);
28    // open WaveMapper = std output of playsound
29    waveOutOpen(@hWO, WAVE_MAPPER, @waveF, 0, 0, 0);
30    vol := volL + volR shl 16;
31    // set volume
32    waveOutSetVolume(hWO, vol);
33    waveOutClose(hWO);
34  end;