code: public function clickImage($label, $x = 1, $y = 1, $additional = false)
      {
          if (! ($form = $this->page->getFormByImage(new SelectByLabel($label)))) {
              return false;
          }
          $success = $this->load(
                  $form->getAction(),
                  $form->submitImage(new SelectByLabel($label), $x, $y, $additional));
  
          return ($success ? $this->getContent() : $success);
      }
docs: Clicks the submit image by some kind of label.
  Usually the alt tag or the nearest equivalent.
  The owning form will be submitted by this.
  Clicking outside of the boundary of the coordinates will result in a failure.
  
  @param string $label    ID attribute of button.
  @param int $x       X-coordinate of imaginary click.
  @param int $y       Y-coordinate of imaginary click.
  @param hash $additional Additional form data.
  
  @return string/boolean  Page on success.