66      * @param string $src
72         string $src,  argument
75         return static::doDecode($src, true, $strictPadding);
96      * @param string $src
103         string $src  argument
105         return static::doEncode($src, false, false);
111      * @param string $src
118         string $src  argument
120         return static::doEncode($src, true, true);
126      * @param string $src
133         string $src  argument
135         return static::doEncode($src, true, false);
142      * @param int $src
146     protected static function decode5Bits(int $src): int  argument
151         $ret += (((0x60 - $src) & ($src - 0x7b)) >> 8) & ($src - 96);
154         $ret += (((0x31 - $src) & ($src - 0x38)) >> 8) & ($src - 23);
165      * @param int $src
169     protected static function decode5BitsUpper(int $src): int  argument
174         $ret += (((0x40 - $src) & ($src - 0x5b)) >> 8) & ($src - 64);
177         $ret += (((0x31 - $src) & ($src - 0x38)) >> 8) & ($src - 23);
186      * @param int $src
190     protected static function encode5Bits(int $src): string  argument
195         $diff -= ((25 - $src) >> 8) & 73;
197         return pack('C', $src + $diff);
206      * @param int $src
210     protected static function encode5BitsUpper(int $src): string  argument
215         $diff -= ((25 - $src) >> 8) & 41;
217         return pack('C', $src + $diff);
254      * @param string $src
263         string $src,  argument
273         $srcLen = strlen($src);
280                     if ($src[$srcLen - 1] === '=') {
293             $src = rtrim($src, '=');
294             $srcLen = strlen($src);
302             $chunk = unpack('C*', substr($src, $i, 8));
333             $chunk = unpack('C*', substr($src, $i, $srcLen - $i));
466      * @param string $src
474         string $src,  argument
484         $srcLen = strlen($src);
489             $chunk = unpack('C*', substr($src, $i, 5));
508             $chunk = unpack('C*', substr($src, $i, $srcLen - $i));