code: protected function goToIFDEntries()
      {
          fseek($this->FileResource, 4);
  
          $ifdOffsetFormat = $this->isLittleEndian() ? 'VIFDoffset' : 'NIFDoffset';
          $data = unpack($ifdOffsetFormat, fread($this->FileResource, 4));
  
          fseek($this->FileResource, $data['IFDoffset']);
      }
docs: The remaining 4 bytes in the header are the offset to the IFD.