zLIB komprimiert nuuuur ein paar kb

[hedie]

hallo

ich verwende folgende zLIB http://www.dellapasqua.com/delphizlib/

Mein Code sieht so aus:

Delphi-Quellcode:

 

procedure Compress(InputFileName, OutputFileName: string);
var InputStream, OutputStream: TFileStream;
  CompressionStream: TZCompressionStream;
begin
  InputStream:=TFileStream.Create(InputFileName, fmOpenRead);
  try
    OutputStream:=TFileStream.Create(OutputFileName, fmCreate);
    try
      CompressionStream:=TZCompressionStream.Create(OutputStream, zcMax);
      try
        CompressionStream.CopyFrom(InputStream, InputStream.Size);
      finally
        CompressionStream.Free;
      end;
    finally
      OutputStream.Free;
    end;
  finally
    InputStream.Free;
  end;
end;

procedure Decompress(InputFileName, OutputFileName: string);
var InputStream, OutputStream: TFileStream;
  DeCompressionStream: TZDeCompressionStream;
  Buf: array[0..4095] of Byte;
  Count: Integer;
begin
  InputStream:=TFileStream.Create(InputFileName, fmOpenRead);
  try
    OutputStream:=TFileStream.Create(OutputFileName, fmCreate);
    try
      DecompressionStream := TZDecompressionStream.Create(InputStream);
      try
        while true do
        begin
          Count := DecompressionStream.Read(Buf[0], SizeOf(Buf));
          if Count = 0 then
            break
          else
            OutputStream.Write(Buf[0], Count);
        end;
      finally
        DecompressionStream.Free;
      end;
    finally
      OutputStream.Free;
    end;
  finally
    InputStream.Free;
  end;
end;

procedure TForm1.SpeedButton3Click(Sender: TObject);
begin
  if Opendialog1.Execute and SaveDialog1.Execute then Compress(OpenDialog1.FileName,SaveDialog1.FileName);
end;

procedure TForm1.SpeedButton4Click(Sender: TObject);
begin

  if Opendialog1.Execute and Savedialog2.Execute then DeCompress(OpenDialog1.FileName,SaveDialog2.FileName);

end;

Doch selbst bei angabe von zcMax ist der unterschied bei einer 1.57MB MP3 Datei gerademal ca 20kb ( nachher 1.55MB)
bei einem 70MB grossen Video sind es ca 3 MB.....

Ist die Komprimierungsrate von zLIB tatsächlich so schlecht oder mache ich etwas falsch?

Hoffe ihr könnt mir helfen....

Danke schonmal