本例效果图:

unit Unit1;interfaceusesWindows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,Dialogs, StdCtrls, ExtCtrls, ComCtrls;typeTForm1 = class(TForm)OpenDialog1: TOpenDialog;Timer1: TTimer;Button1: TButton;Button2: TButton;Button3: TButton;ProgressBar1: TProgressBar;ProgressBar2: TProgressBar;procedure FormCreate(Sender: TObject);procedure Button1Click(Sender: TObject);procedure Button2Click(Sender: TObject);procedure Button3Click(Sender: TObject);procedure FormDestroy(Sender: TObject);procedure Timer1Timer(Sender: TObject);end;varForm1: TForm1;implementation{$R *.dfm}uses Bass;varhs: HSTREAM;  {流句柄}procedure TForm1.FormCreate(Sender: TObject);
beginTimer1.Interval := 100;Timer1.Enabled := False;ProgressBar1.Align := alLeft;ProgressBar2.Align := alRight;ProgressBar1.Orientation := pbVertical;ProgressBar2.Orientation := pbVertical;ProgressBar1.Width := 20;ProgressBar2.Width := 20;ProgressBar1.Max := MAXWORD div 2;ProgressBar2.Max := MAXWORD div 2;if HiWord(BASS_GetVersion) <> BASSVERSION thenMessageBox(0, '"Bass.dll" 文件版本不合适! ', nil, MB_ICONERROR);if not BASS_Init(-1, 44100, 0, 0, nil) then ShowMessage('初始化错误');
end;{打开}
procedure TForm1.Button1Click(Sender: TObject);
varMp3Path: AnsiString;
beginBASS_StreamFree(hs);Timer1.Enabled := False;OpenDialog1.Filter := 'Mp3 文件(*.mp3)|*.mp3|Wav 文件(*.wav)|*wav';if OpenDialog1.Execute thenMp3Path := AnsiString(OpenDialog1.FileName);hs := BASS_StreamCreateFile(False, PAnsiChar(Mp3Path), 0, 0, 0);if hs < BASS_ERROR_ENDED thenText := '打开失败'elseText := Mp3Path;
end;{播放}
procedure TForm1.Button2Click(Sender: TObject);
beginBASS_ChannelPlay(hs, False);Timer1.Enabled := True;
end;{暂停}
procedure TForm1.Button3Click(Sender: TObject);
beginBASS_ChannelPause(hs);Timer1.Enabled := False;
end;{显示左右声道的峰值}
procedure TForm1.Timer1Timer(Sender: TObject);
varLevel: Cardinal;
beginLevel := BASS_ChannelGetLevel(hs); {其低16位为左声道峰值; 高16位为右声道峰值}ProgressBar1.Position := LoWord(Level);ProgressBar2.Position := HiWord(Level);
end;procedure TForm1.FormDestroy(Sender: TObject);
beginBASS_Free;
end;end.

窗体文件:

object Form1: TForm1Left = 222Top = 114Caption = 'Form1'ClientHeight = 113ClientWidth = 243Color = clBtnFaceFont.Charset = DEFAULT_CHARSETFont.Color = clWindowTextFont.Height = -11Font.Name = 'Tahoma'Font.Style = []OldCreateOrder = FalsePosition = poDesignedOnCreate = FormCreateOnDestroy = FormDestroyPixelsPerInch = 96TextHeight = 13object Button1: TButtonLeft = 83Top = 17Width = 75Height = 25Caption = #25171#24320TabOrder = 0OnClick = Button1Clickendobject Button2: TButtonLeft = 83Top = 48Width = 75Height = 25Caption = #25773#25918TabOrder = 1OnClick = Button2Clickendobject Button3: TButtonLeft = 83Top = 79Width = 75Height = 25Caption = #26242#20572TabOrder = 2OnClick = Button3Clickendobject ProgressBar1: TProgressBarLeft = 8Top = 74Width = 69Height = 17TabOrder = 3endobject ProgressBar2: TProgressBarLeft = 164Top = 74Width = 77Height = 17TabOrder = 4endobject OpenDialog1: TOpenDialogLeft = 192Top = 8endobject Timer1: TTimerOnTimer = Timer1TimerLeft = 40Top = 8end
end