用多媒体库 Bass.dll 播放 mp3 [15] - 设置与获取播放速度
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用多媒体库 Bass.dll 播放 mp3 [15] - 设置与获取播放速度
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; Button4: TButton; procedure FormCreate(Sender: TObject); procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure TrackBar1Change(Sender: TObject); procedure FormDestroy(Sender: TObject); procedure Button4Click(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} uses Bass; var hs: HSTREAM; {流句柄} procedure TForm1.FormCreate(Sender: TObject); begin TrackBar1.ShowSelRange := False; TrackBar1.Height := 23; TrackBar1.Max := 100000; TrackBar1.Min := 100; TrackBar1.Position := 44100; 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); hs := BASS_StreamCreateFile(False, PAnsiChar(Mp3Path), 0, 0, 0); if hs < BASS_ERROR_ENDED then Text := '打开失败' else begin Text := string(Mp3Path); Button4.Click; 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; {原速} procedure TForm1.Button4Click(Sender: TObject); begin TrackBar1.Position := 44100; end; {设置和获取播放速度} procedure TForm1.TrackBar1Change(Sender: TObject); var freq: Single; begin freq := 44100; BASS_ChannelSlideAttribute(hs, BASS_ATTRIB_FREQ, TrackBar1.Position, 0); BASS_ChannelGetAttribute(hs, BASS_ATTRIB_FREQ, freq); Label1.Caption := Format('当前速度比例: %f%%', [freq/44100]); end; procedure TForm1.FormDestroy(Sender: TObject); begin BASS_Free; end; end.窗体文件:
object Form1: TForm1 Left = 205 Top = 107 Caption = 'Form1' ClientHeight = 119 ClientWidth = 286 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 = 32 Top = 59 Width = 31 Height = 13 Caption = 'Label1' end object Button1: TButton Left = 24 Top = 17 Width = 75 Height = 25 Caption = #25171#24320 TabOrder = 0 OnClick = Button1Click end object Button2: TButton Left = 105 Top = 17 Width = 75 Height = 25 Caption = #25773#25918 TabOrder = 1 OnClick = Button2Click end object Button3: TButton Left = 186 Top = 17 Width = 75 Height = 25 Caption = #26242#20572 TabOrder = 2 OnClick = Button3Click end object TrackBar1: TTrackBar Left = 24 Top = 78 Width = 237 Height = 32 TabOrder = 3 OnChange = TrackBar1Change end object Button4: TButton Left = 186 Top = 48 Width = 75 Height = 25 Caption = #21407#36895 TabOrder = 4 OnClick = Button4Click end object OpenDialog1: TOpenDialog Left = 256 end endposted on 2008-08-22 23:04 万一 阅读(3803) 评论(5) 编辑 收藏
标签:end,Bass,BASS,TForm1,TObject,15,播放,procedure,Sender 来源: https://blog.51cto.com/u_14617575/2746642