[SOLVED] BASS - No Volume Control

[QEnnay]

Hi I am using BASS to play MP3 and it does it very nicely. But the Volume Up/Down does not work.

I am using Lazarus 2.0.8 on Linux Mnt 19.3+Cinnamon. There is only a single standard option in the Mint-Sound Output dialog.

Code: Pascal  [Select][+][-]

1. function BASS_SetVolume: Single; {$IFDEF MSWINDOWS}stdcall{$ELSE}cdecl{$ENDIF}; external bassdll;
2.  
3. procedure TfrmMain.btnVolUpClick(Sender: TObject);
4. begin
5.   if trackVol < 100 then  // Got the 100 from Bass unit {0..100}
6.     Inc(trackVol,5);
7.   BASS_SetVolume(trackVol);
8.   lblVol.Caption:=IntToStr(trackVol);
9. end;
10.  

The numbers roll around OK, but the sound does not change. Do I need to initialize the Sound somewhere for BASS?

Thanks

[varianus]

BASS volume goes from  0.0 (silent) to 1.0 (max). , see documentation at http://www.un4seen.com/doc/#bass/BASS_SetVolume.html

so your code should become (untested)

Code: Pascal  [Select][+][-]

1. procedure TfrmMain.btnVolUpClick(Sender: TObject);
2. begin
3.   if trackVol < 100 then  // Got the 100 from Bass unit {0..100}
4.     Inc(trackVol,5);
5.   BASS_SetVolume(trackVol * (1.0 /100));
6.   lblVol.Caption:=IntToStr(trackVol);
7. end;

[Cyrax]

Correct definition for this function should be this according to the documentation.

Code: Pascal  [Select][+][-]

1. function BASS_SetVolume(AValue: Single):boolean; {$IFDEF MSWINDOWS}stdcall{$ELSE}cdecl{$ENDIF}; external bassdll;

[winni]

Hi!

Nearly all values for set and get in BASS have a range from 0.0 .. 1.0
The stereo balance (B_PAN) has a range from -1.0 .. +1.0

Winni

[QEnnay]

Ahhh, OK, thanks everyone. I got the 0..100 from BASS, line #577

Code: Pascal  [Select][+][-]

1.   BASS_SAMPLE = record
2.     freq: DWORD;        // default playback rate
3.     volume: Single;     // default volume (0-100)
4.  

[QEnnay]

Code: Pascal  [Select][+][-]

1.   BASS_SetVolume(trackVol * (1.0 /100));
2.  

Tested!
Thanks, that works perfectly.