Classes/Utility/JpegExifOrient.php
protected static function read_2_bytes($handle)
    {
        $c1 = fgetc($handle);
        if ($c1 === false) {
            throw new \RuntimeException('Premature EOF in JPEG file', 1363533326);
        }
        $c2 = fgetc($handle);
        if ($c2 === false) {
            throw new \RuntimeException('Premature EOF in JPEG file', 1363533326);
        }
        return (ord($c1) << 8) + (ord($c2));
    }
protected static function read_2_bytes($handle)
    {
        $c1 = fgetc($handle);
        if ($c1 === false) {
            throw new \RuntimeException('Premature EOF in JPEG file', 1363533326);
        }
        $c2 = fgetc($handle);
        if ($c2 === false) {
            throw new \RuntimeException('Premature EOF in JPEG file', 1363533326);
        }
        return (ord($c1) << 8) + (ord($c2));
    }
Reads 2 bytes, converts them to unsigned int
Remark: All 2-byte quantities in JPEG markers are MSB first.

@param resource $handle
@return integer
@throws \RuntimeException