public static function bitrateLookup($frmsizecod) {
    // LSB is whether padding is used or not
    $padding     = (bool) ($frmsizecod & 0x01);
    $framesizeid =        ($frmsizecod & 0x3E) >> 1;

    static $bitrateLookup = array(
       0 =>  32000,
       1 =>  40000,
       2 =>  48000,
       3 =>  56000,
       4 =>  64000,
       5 =>  80000,
       6 =>  96000,
       7 => 112000,
       8 => 128000,
       9 => 160000,
      10 => 192000,
      11 => 224000,
      12 => 256000,
      13 => 320000,
      14 => 384000,
      15 => 448000,
      16 => 512000,
      17 => 576000,
      18 => 640000,
    );
    return (isset($bitrateLookup[$framesizeid]) ? $bitrateLookup[$framesizeid] : false);
  }