ShowGammaAdjustmentDlg example for Delphi

procedure TForm1.ShowGammaAdjustmentDlg1Click(Sender: TObject); 
var
   nRet: L_INT; 
begin
   LEADDlgColor1.GammaRedValue:= 50; 
   LEADDlgColor1.GammaGreenValue:= 50; 
   LEADDlgColor1.GammaBlueValue:= 50; 
   LEADDlgColor1.GammaAllChannels:= True; 
   LEADDlgColor1.DlgFlags:= DLG_GAMMAADJUSTMENT_SHOW_PREVIEW Or
                             DLG_GAMMAADJUSTMENT_SHOW_TOOL_ZOOMLEVEL; 
   LEADDlgColor1.LEADImage:= LEADImage1; 
   LEADDlgColor1.LEADDlgService:= LEADDlgService1; 
   nRet:= LEADDlgColor1.ShowGammaAdjustmentDlg ( Self ); 
   if ( nRet = SUCCESS_DLG_OK ) then
   begin
      LEADImage1.GammaCorrect ( LEADDlgColor1.GammaRedValue ); 
   end; 
end;