IMagick error: Safe mode restricts user to read image

<?php
class Image
{
  public $size;  // výsledná velikost (čtverec)
  public $imgFile;  // cesta k souboru
  public $bc;  // barva pozadí, zadáno jako pole array(0-255, 0-255, 0-255)
  
  private $img;
  
  public function create()
  {
    $this->img = imagecreatetruecolor($this->size, $this->size);
    $bc = imagecolorallocate($this->img, $this->bc[0], $this->bc[1], $this->bc[2]);
    imagefill($this->img, 0, 0, $bc);
  }
  
  public function calculateSize()
  {
    list($w, $h) = getimagesize($this->imgFile);
    if ($w >= $h)
    {
      $height = round($h * $this->size / $w);
      $width = $this->size;
    }
    if ($h > $w)
    {
      $width = round($w * $this->size / $h);
      $height = $this->size;
    }
    return array($width, $height, $w, $h);
  }

  public function addImage()
  {
    $i = imagecreatefromjpeg($this->imgFile);

    list($width, $height, $w, $h) = $this->calculateSize();
    
    $kx = round(($this->size - $width) / 2);
    $ky = round(($this->size - $height) / 2);
    
    imagecopyresampled($this->img, $i, $kx, $ky, 0, 0, $width, $height, $w, $h);
  }
  
  public function getScreen()
  {
    $this->create();
    $this->addImage();
    header('Content-type: image/jpeg');
    imagejpeg($this->img);
  }
  
  public function save($dst)
  {
    $this->create();
    $this->addImage();
    imagejpeg($this->img, $dst);
  }
}

$img = new Image();
$img->size = 300;
$img->imgFile = "./img/e03.jpg";
$img->bc = array(0, 150, 150);
$img->save("maly_obrazek.jpeg");
$img->getScreen();