用多媒体库 Bass.dll 播放 mp3 [13] - 混响(Reverb)效果
本例效果图:代码文件:
unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls, ComCtrls; type TForm1 = class(TForm) OpenDialog1: TOpenDialog; Button1: TButton; Button2: TButton; Button3: TButton; TrackBar1: TTrackBar; Label1: TLabel; procedure FormCreate(Sender: TObject); procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure FormDestroy(Sender: TObject); procedure TrackBar1Change(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} uses Bass; var hs: HSTREAM; {流句柄} reverb: BASS_DX8_REVERB; {混响的参数结构, 不能是局部变量; 本例只测试了结构中的 fReverbTime 参数} fx: HFX; {DX 的效果句柄} procedure TForm1.FormCreate(Sender: TObject); begin {reverb.fReverbTime: 0.001 - 3000.0; 默认 1000} TrackBar1.Min := 1; TrackBar1.Max := 3000; TrackBar1.Position := 1000; if HiWord(BASS_GetVersion) <> BASSVERSION then MessageBox(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); var Mp3Path: AnsiString; begin BASS_StreamFree(hs); OpenDialog1.Filter := 'Mp3 文件(*.mp3)|*.mp3|Wav 文件(*.wav)|*wav'; if OpenDialog1.Execute then Mp3Path := AnsiString(OpenDialog1.FileName); {实现混响等效果, 需要指定 BASS_SAMPLE_FX 参数} hs := BASS_StreamCreateFile(False, PAnsiChar(Mp3Path), 0, 0, BASS_SAMPLE_FX); if hs < BASS_ERROR_ENDED then Text := '打开失败' else begin Text := string(Mp3Path); {设置并返回效果句柄} fx := BASS_ChannelSetFX(hs, BASS_FX_DX8_REVERB, 0); end; end; {播放} procedure TForm1.Button2Click(Sender: TObject); begin BASS_ChannelPlay(hs, False); end; {暂停} procedure TForm1.Button3Click(Sender: TObject); begin BASS_ChannelPause(hs); end; procedure TForm1.FormDestroy(Sender: TObject); begin BASS_Free; end; procedure TForm1.TrackBar1Change(Sender: TObject); begin reverb.fReverbTime := TrackBar1.Position; BASS_FXSetParameters(fx, @reverb); Label1.Caption := Format('混响时间: %f', [reverb.fReverbTime]); end; end.窗体文件:
object Form1: TForm1 Left = 222 Top = 114 Caption = 'Form1' ClientHeight = 119 ClientWidth = 299 Color = clBtnFace Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -11 Font.Name = 'Tahoma' Font.Style = [] OldCreateOrder = False Position = poDesigned OnCreate = FormCreate OnDestroy = FormDestroy PixelsPerInch = 96 TextHeight = 13 object Label1: TLabel Left = 40 Top = 67 Width = 52 Height = 13 Caption = #28151#21709#26102#38388':' end object Button1: TButton Left = 32 Top = 25 Width = 75 Height = 25 Caption = #25171#24320 TabOrder = 0 OnClick = Button1Click end object Button2: TButton Left = 113 Top = 25 Width = 75 Height = 25 Caption = #25773#25918 TabOrder = 1 OnClick = Button2Click end object Button3: TButton Left = 194 Top = 25 Width = 75 Height = 25 Caption = #26242#20572 TabOrder = 2 OnClick = Button3Click end object TrackBar1: TTrackBar Left = 26 Top = 86 Width = 243 Height = 23 ShowSelRange = False TabOrder = 3 OnChange = TrackBar1Change end object OpenDialog1: TOpenDialog end endposted on 2008-08-22 16:04 万一 阅读(3452) 评论(0) 编辑 收藏