app/code/community/Nexcessnet/Turpentine/Helper/Data.php
public function freeze($data) {
        Varien_Profiler::start('turpentine::helper::data::freeze');
        $frozenData = $this->urlBase64Encode(
            $this->_getCrypt()->encrypt(
                gzdeflate(
                    serialize($data),
                    self::COMPRESSION_LEVEL ) ) );
        Varien_Profiler::stop('turpentine::helper::data::freeze');
        return $frozenData;
    }
public function freeze($data) {
        Varien_Profiler::start('turpentine::helper::data::freeze');
        $frozenData = $this->urlBase64Encode(
            $this->_getCrypt()->encrypt(
                gzdeflate(
                    serialize($data),
                    self::COMPRESSION_LEVEL ) ) );
        Varien_Profiler::stop('turpentine::helper::data::freeze');
        return $frozenData;
    }
public function freeze ( $ data ) { Varien_Profiler :: start ( 'turpentine::helper::data::freeze' ) ; $ frozenData = $ this -> urlBase64Encode ( $ this -> _getCrypt ( ) -> encrypt ( gzdeflate ( serialize ( $ data ) , self :: COMPRESSION_LEVEL ) ) ) ; Varien_Profiler :: stop ( 'turpentine::helper::data::freeze' ) ; return $ frozenData ; }
Serialize a variable into a string that can be used in a URL

Using gzdeflate to avoid the checksum/metadata overhead in gzencode and
gzcompress

@param  mixed $data
@return string
Serialize a variable into a string that can be used in a URL