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我正在使用 C++ 在 Rad Studio 中为 Windows 构建视频播放器应用程序。我已经实现了基本功能，即加载视频、播放、暂停、音量控制现在我想实现快速播放选项，例如用户将单击一个按钮，视频将以双倍速度播放，就像 VLC 播放器中的 2x 一样。代码如下我该怎么做

  TForm2 *Form2;

__fastcall TForm2::TForm2(TComponent* Owner) : TForm(Owner)
{
}

void __fastcall TForm2::OpenButtonClick(TObject *Sender){
  OpenDialog1->Filter = TMediaCodecManager::GetFilterString();    

  if (OpenDialog1->Execute())
  {
    PauseButton->Enabled = true;
    ClearButton->Enabled = true;
    MediaPlayer1->FileName = OpenDialog1->FileName;

    if (MediaPlayer1->Media != NULL)
    {``
      Label1->Text = IntToStr((int) MediaPlayer1->Media>VideoSize.Truncate().X) + "x" +
        IntToStr((int) MediaPlayer1->Media->VideoSize.Truncate().Y)+ "px " +
        IntToStr((__int64) MediaPlayer1->Media->Duration / MediaTimeScale) + "s";

      TrackBar1->Max = MediaPlayer1->Media->Duration;
      VolumeTrack->Value = 1 - MediaPlayer1->Media->Volume;

      MediaPlayer1->Play();
    }
  }
}

void __fastcall TForm2::PauseButtonClick(TObject *Sender)
{``
  if (MediaPlayer1->State == TMediaState::Playing)
  {
    PauseButton->Text = "Play";
    MediaPlayer1->Stop();
  }
  else
  {
    PauseButton->Text = "Pause";
    MediaPlayer1->Play();
  }
}

void __fastcall TForm2::TrackBar1Change(TObject *Sender)
{
  if (TrackBar1->Tag == 0)
  {
    MediaPlayer1->CurrentTime = (__int64) TrackBar1->Value;
  }
}

void __fastcall TForm2::Timer1Timer(TObject *Sender)
{
  TrackBar1->Tag = 1;
  TrackBar1->Value = MediaPlayer1->CurrentTime;
  TrackBar1->Tag = 0;
}

void __fastcall TForm2::CheckBox1Change(TObject *Sender)
{
  MediaPlayerControl1->Visible = CheckBox1->IsChecked;
}

void __fastcall TForm2::VolumeTrackChange(TObject *Sender)
{
  MediaPlayer1->Volume = 1 - VolumeTrack->Value;
}

void __fastcall TForm2::ClearButtonClick(TObject *Sender)
{
  MediaPlayer1->Clear();
  PauseButton->Enabled = false;
  ClearButton->Enabled = false;
}

void __fastcall TForm2::FastForwardClick(TObject *Sender)
{
//this is where I want to implement fast video 2x functionality
}`
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