void __fastcall TMainForm::BtnChangeClick(TObject *Sender)
{
  if( frmVideoForm->FilterGraph->Active==FALSE ) frmVideoForm->FilterGraph->Active=TRUE;

  if( BtnChange->Tag==0 )
  {
    frmVideoForm->Visible = false;

    frmVideoForm->VideoWindow->Parent = Panel1;

    frmVideoForm->VideoWindow->Left   = 0;
    frmVideoForm->VideoWindow->Top    = 0;
    frmVideoForm->VideoWindow->Width  = 182;
    frmVideoForm->VideoWindow->Height = 129;

    BtnChange->Tag=1;
  }
  else
  {
    frmVideoForm->Visible = true;

    frmVideoForm->VideoWindow->Parent = frmVideoForm->Panel1;
    frmVideoForm->VideoWindow->Left   = 0;
    frmVideoForm->VideoWindow->Top    = 0;
    frmVideoForm->VideoWindow->Width  = frmVideoForm->Panel1->Width;
    frmVideoForm->VideoWindow->Height = frmVideoForm->Panel1->Height;

    BtnChange->Tag=0;
  }

  frmVideoForm->VideoWindow->RefreshVideoWindow();
}