使用带有Delphi的BASS dll创建flac文件或flac流

时间:2018-09-08 14:40:16

标签: delphi audio encode flac bass

我正在玩http://www.un4seen.com/中的BASS。

我需要根据用户在麦克风上创建的flac文件(16位)或flac流。

我已经在BASS源代码中看到了这个演示。 还有一个bassenc_flac.dll以及以下功能:

function BASS_Encode_FLAC_Start(handle:DWORD; options:PChar; flags:DWORD; proc:ENCODEPROCEX; user:Pointer): HENCODE; {$IFDEF MSWINDOWS}stdcall{$ELSE}cdecl{$ENDIF}; external bassencflacdll;
function BASS_Encode_FLAC_StartFile(handle:DWORD; options:PChar; flags:DWORD; filename:PChar): HENCODE; {$IFDEF MSWINDOWS}stdcall{$ELSE}cdecl{$ENDIF}; external bassencflacdll;

如何更改下一个代码以将音频编码为flac文件或流?

从RecordTest BASS演示

(* This is called while recording audio *)
function RecordingCallback(Handle: HRECORD; buffer: Pointer; length: DWORD; user: Pointer): boolean; stdcall;
var level:dword;
begin
    level:=BASS_ChannelGetLevel(Handle);
    // Copy new buffer contents to the memory buffer
    Form1.WaveStream.Write(buffer^, length);
    // Allow recording to continue
    Result := True;
end;

(* Start recording to memory *)
procedure TForm1.StartRecording;
begin
    if ComboBox1.ItemIndex < 0 then Exit;
    if WaveStream.Size > 0 then
    begin   // free old recording
        BASS_StreamFree(chan);
        WaveStream.Clear;
    end;
    // generate header for WAV file
    with WaveHdr do
    begin
        riff := 'RIFF';
        len := 36;
        cWavFmt := 'WAVEfmt ';
        dwHdrLen := 16;
        wFormat := 1;
        wNumChannels := 2;
        dwSampleRate := 44100;
        wBlockAlign := 4;
        dwBytesPerSec := 176400;
        wBitsPerSample := 16;
        cData := 'data';
        dwDataLen := 0;
    end;
    WaveStream.Write(WaveHdr, SizeOf(WAVHDR));
    // start recording @ 44100hz 16-bit stereo
    rchan := BASS_RecordStart(44100, 2, 0, @RecordingCallback, nil);
    if rchan = 0 then
    begin
        MessageDlg('Couldn''t start recording!', mtError, [mbOk], 0);
        WaveStream.Clear;
    end
    else
    begin
        bRecord.Caption := 'Stop';
        bPlay.Enabled := False;
        bSave.Enabled := False;
    end;
end;


(* Stop recording *)
procedure TForm1.StopRecording;
var
    i: integer;
  he:BassEnc.HENCODE;
begin
    BASS_ChannelStop(rchan);
    bRecord.Caption := 'Record';
    // complete the WAV header
    WaveStream.Position := 4;
    i := WaveStream.Size - 8;
    WaveStream.Write(i, 4);
    i := i - $24;
    WaveStream.Position := 40;
    WaveStream.Write(i, 4);
    WaveStream.Position := 0;
    // create a stream from the recorded data
    chan := BASS_StreamCreateFile(True, WaveStream.Memory, 0, WaveStream.Size, 0);
    if chan <> 0 then
    begin
        // enable "Play" & "Save" buttons
        bPlay.Enabled := True;
        bSave.Enabled := True;
    end
    else
        MessageDlg('Error creating stream from recorded data!', mtError, [mbOk], 0);
    if SaveDialog.Execute then
       WaveStream.SaveToFile(SaveDialog.FileName);

end;

1 个答案:

答案 0 :(得分:1)

我已更新代码,原因是注释显示以前的编码器版本工作不正确。我完全同意这些评论。

为了创建FLAC编码器,我们应该访问un4seen网站并下载以下文件:

  1. BASS音频库2.4
  2. BASSFLAC 2.4.4
  3. BASSenc 2.4.14
  4. BASSenc_FLAC 2.4.1.1

浏览这些文件夹并查找下一个文件:

  1. bass.pas
  2. bassenc.pas
  3. bassenc_flac.pas

现在将这些pas文件放入一个文件夹,然后通过Library选项将其添加到Delphi's
完成此步骤后,创建新项目,将其保存在单独的文件夹中。
然后浏览BASS_XXX文件夹并查找*.dll文件。
将它们合并到保存项目的文件夹中!

现在让我们编写一些代码。

添加到uses子句bass.pasbassenc.pasbassenc_flac.pas中。然后复制下面显示的代码。

  uses ..., BASS, BASSEnc, BASSEnc_FLAC;

  ...

  TForm1 = class(TForm)
    ProgressBar1: TProgressBar;      
  public
    { Public declarations }
    procedure StartEncode(SourceFileName, OutputFileName: String);
    procedure StopEncode;
  end;

...

procedure TForm1.StartEncode(SourceFileName, OutputFileName: String);
var
  PercentDone: Cardinal;
  Buffer: array [0..1024] of Byte;
begin
  Channel := BASS_StreamCreateFile(false, PChar(SourceFileName), 0, 0, BASS_MUSIC_DECODE or BASS_UNICODE);
  BASSEnc_FLAC.BASS_Encode_FLAC_StartFile(Channel, 0, BASS_ENCODE_FP_AUTO or BASS_UNICODE, PChar(OutputFileName));
  while BASS_ChannelIsActive(Channel) > 0 do
  begin
    BASS_ChannelGetData(Channel, @Buffer, 1024);
    PercentDone := Trunc(100 * (BASS_ChannelGetPosition(Channel, BASS_POS_BYTE) / BASS_ChannelGetLength(Channel, BASS_POS_BYTE)));
    ProgressBar1.Position := PercentDone;
  end;
  StopEncode;
end;

procedure TForm1.StopEncode;
begin
  BASS_Encode_Stop(Channel);
  BASS_StreamFree(Channel);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  BASS_Init(-1, 44100, 0, Application.Handle, nil);
  try   
    // Set name of file to convert it to FLAC and save it with output name
    StartEncode('SourceFileName', 'OutputFileName');
  finally
    BASS.BASS_Free;
  end;
end;

一个通知:
确实,使用以前版本的代码编码的文件具有错误的标头(在Notepad.exe中打开文件时,我可以看到它)。更新代码后,我可以看到有效的标头(当然,在记事本中,因为我没有使用音频文件的专业工具)。
现在,您甚至不需要像我之前所做的那样向BASS添加插件。 从那时起,我认为编码器可以按预期工作。