public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $image_styles = image_style_options(FALSE);
    $form['landscape'] = [
      '#type' => 'select',
      '#title' => t('Landscape image style'),
      '#options' => $image_styles,
      '#default_value' => $this->configuration['landscape'],
      '#description' => t('Select the image style for landscape images'),
      '#required' => TRUE,
    ];
    $form['portrait'] = [
      '#type' => 'select',
      '#title' => t('Portrait'),
      '#options' => $image_styles,
      '#default_value' => $this->configuration['portrait'],
      '#description' => t('Select the image style for portrait images'),
      '#required' => TRUE,
    ];
    return $form;
  }
public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
    $image_styles = image_style_options(FALSE);
    $form['landscape'] = [
      '#type' => 'select',
      '#title' => t('Landscape image style'),
      '#options' => $image_styles,
      '#default_value' => $this->configuration['landscape'],
      '#description' => t('Select the image style for landscape images'),
      '#required' => TRUE,
    ];
    $form['portrait'] = [
      '#type' => 'select',
      '#title' => t('Portrait'),
      '#options' => $image_styles,
      '#default_value' => $this->configuration['portrait'],
      '#description' => t('Select the image style for portrait images'),
      '#required' => TRUE,
    ];
    return $form;
  }
{@inheritdoc}