JPanel layouts. See comment below for a preview.

HelloApp.java

package example;

import javax.swing.*;
import java.awt.*;
import java.lang.reflect.InvocationTargetException;
import java.net.URL;

@SuppressWarnings("ALL")
public class HelloApp {
   private final JFrame frame;
   private final JLabel videoLabel;

   public static void main(final String[] args) {
      EventQueue.invokeLater(() -> {
         final HelloApp window = new HelloApp();
      });
   }

   public HelloApp() {
      frame = new JFrame("MULTIPLE-TARGET TRACKING");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

      final int width = 800;
      final int height = 500;
      frame.setBounds(0, 0, width, height);
      frame.setLayout(new BorderLayout());

      // Show the frame at the center of the screen
      frame.setLocation(
         (int) (0.5 * Toolkit.getDefaultToolkit().getScreenSize().width - width / 2),
         (int) (0.5 * Toolkit.getDefaultToolkit().getScreenSize().height - height / 2)
      );
      frame.setVisible(true);

      // Main panel, direct child of the JFrame
      final JPanel panel = new JPanel(new BorderLayout());
      frame.getContentPane().add(panel, BorderLayout.CENTER);

      // Upper section of the UI
      final JButton startButton = new JButton("Start / Replay");
      startButton.addActionListener(event -> {
            // Frame processing should run in a separate (non-EDT) thread to avoid freezing the UI.
            // To spawn a thread you can use a bare Thread, or look at ExecutorService.
            //
            // Also remember not to press the button more than once, or multiple threads
            // will be updating the shown image
            final Thread thread = new Thread(() -> {
               try {
                  playVideo();
               } catch (final InterruptedException | InvocationTargetException ex) {
                  ex.printStackTrace();
               }
            });

            thread.start();
         }
      );

      final Box upperLeftBox = Box.createHorizontalBox();
      upperLeftBox.add(startButton);
      upperLeftBox.add(Box.createHorizontalStrut(10));
      upperLeftBox.add(new JButton("Close"));

      final Box upperRightBox = Box.createHorizontalBox();
      upperRightBox.add(new JButton("Capture camera"));

      final JPanel upperPanel = new JPanel(new BorderLayout());
      upperPanel.add(upperLeftBox, BorderLayout.LINE_START);
      upperPanel.add(upperRightBox, BorderLayout.LINE_END);
      upperPanel.setBorder(
         BorderFactory.createCompoundBorder(
            BorderFactory.createEmptyBorder(10, 10, 10, 10),
            BorderFactory.createLineBorder(Color.BLACK, 2)
         )
      );

      // Middle section of the UI
      videoLabel = new JLabel();
      videoLabel.setBorder(BorderFactory.createLineBorder(Color.RED));

      final JPanel middlePanel = new JPanel(new BorderLayout());
      middlePanel.add(videoLabel, BorderLayout.CENTER);

      final JPanel settingsPanel = new JPanel(new GridBagLayout());
      settingsPanel.setBorder(BorderFactory.createLineBorder(Color.GREEN));

      final GridBagConstraints gc = new GridBagConstraints();
      gc.fill = GridBagConstraints.HORIZONTAL;
      gc.anchor = GridBagConstraints.NORTH;
      gc.insets = new Insets(3, 5, 3, 5);
      settingsPanel.add(new JLabel("Learning rate"), gc);

      gc.gridx = 1;
      gc.weightx = 1.0;
      settingsPanel.add(new JTextField(10), gc);

      gc.weightx = 0.0;
      gc.gridx = 0;
      gc.gridy = 1;
      settingsPanel.add(new JLabel("Min blob"), gc);

      gc.weightx = 1.0;
      gc.gridx = 1;
      settingsPanel.add(new JTextField(10), gc);

      gc.weighty = 1.0;
      gc.gridx = 0;
      gc.gridy = 2;
      gc.gridwidth = 2;
      settingsPanel.add(new JButton("Submit"), gc);

      final Box middleRightBox = Box.createVerticalBox();
      middleRightBox.add(settingsPanel);

      middlePanel.add(middleRightBox, BorderLayout.LINE_END);
      middlePanel.setBorder(
         BorderFactory.createCompoundBorder(
            BorderFactory.createEmptyBorder(0, 10, 0, 10),
            BorderFactory.createLineBorder(Color.BLACK, 2)
         )
      );

      // Bottom section of the UI
      final JPanel bottomPanel = new JPanel(new BorderLayout());
      bottomPanel.add(new JButton("Open file..."), BorderLayout.LINE_START);
      bottomPanel.setBorder(
         BorderFactory.createCompoundBorder(
            BorderFactory.createEmptyBorder(10, 10, 10, 10),
            BorderFactory.createLineBorder(Color.BLACK, 2)
         )
      );

      panel.add(upperPanel, BorderLayout.PAGE_START);
      panel.add(middlePanel, BorderLayout.CENTER);
      panel.add(bottomPanel, BorderLayout.PAGE_END);
   }

   private void playVideo() throws InterruptedException, InvocationTargetException {
      // Loop to showcase how the images change inside the JLabel
      frame.setResizable(false);

      while (true) {
         for (int i = 1; i < 6; i++) {
            // Here we process the frame.
            // Replace this with whatever you need to do
            final URL resource = getClass().getResource("/img" + i + ".jpg");

            // Update the shown image using the EDT thread, otherwise an exception will be thrown
            EventQueue.invokeAndWait(() -> {
               final Icon image = new ImageIcon(resource);
               videoLabel.setIcon(image);
               frame.pack();
            });

            // Simulate 20 FPS
            Thread.sleep(50);
         }
      }
   }
}

Result: