/** Creates sound level related components. */
  private void createSoundLevelIndicators() {
    TransparentPanel localLevelPanel = new TransparentPanel(new BorderLayout(5, 0));
    TransparentPanel remoteLevelPanel = new TransparentPanel(new BorderLayout(5, 0));

    localLevel =
        new InputVolumeControlButton(
            call, ImageLoader.MICROPHONE, ImageLoader.MUTE_BUTTON, false, false);
    remoteLevel =
        new OutputVolumeControlButton(call.getConference(), ImageLoader.HEADPHONE, false, false)
            .getComponent();

    final SoundLevelIndicator localLevelIndicator =
        new SoundLevelIndicator(SoundLevelChangeEvent.MIN_LEVEL, SoundLevelChangeEvent.MAX_LEVEL);
    final SoundLevelIndicator remoteLevelIndicator =
        new SoundLevelIndicator(SoundLevelChangeEvent.MIN_LEVEL, SoundLevelChangeEvent.MAX_LEVEL);

    localLevelPanel.add(localLevel, BorderLayout.WEST);
    localLevelPanel.add(localLevelIndicator, BorderLayout.CENTER);
    remoteLevelPanel.add(remoteLevel, BorderLayout.WEST);
    remoteLevelPanel.add(remoteLevelIndicator, BorderLayout.CENTER);

    GridBagConstraints constraints = new GridBagConstraints();
    constraints.fill = GridBagConstraints.NONE;
    constraints.gridx = 0;
    constraints.gridy = 5;
    constraints.weightx = 0;
    constraints.weighty = 0;
    constraints.insets = new Insets(10, 0, 0, 0);

    add(localLevelPanel, constraints);

    constraints.fill = GridBagConstraints.NONE;
    constraints.gridx = 0;
    constraints.gridy = 6;
    constraints.weightx = 0;
    constraints.weighty = 0;
    constraints.insets = new Insets(5, 0, 10, 0);

    add(remoteLevelPanel, constraints);

    if (!GuiActivator.getConfigurationService()
        .getBoolean(
            "net.java.sip.communicator.impl.gui.main.call." + "DISABLE_SOUND_LEVEL_INDICATORS",
            false)) {
      callPeer.addStreamSoundLevelListener(
          new SoundLevelListener() {
            public void soundLevelChanged(Object source, int level) {
              remoteLevelIndicator.updateSoundLevel(level);
            }
          });
      /*
       * By the time the UI gets to be initialized, the callPeer may have
       * been removed from its Call. As far as the UI is concerned, the
       * callPeer will never have a Call again and there will be no audio
       * levels to display anyway so there is no point in throwing a
       * NullPointerException here.
       */
      if (call != null) {
        call.addLocalUserSoundLevelListener(
            new SoundLevelListener() {
              public void soundLevelChanged(Object source, int level) {
                localLevelIndicator.updateSoundLevel(level);
              }
            });
      }
    }
  }