src/Zend/Filter/Encrypt/Mcrypt.php
public function decrypt($value)
    {
        $cipher = $this->_openCipher();
        $this->_initCipher($cipher);
        $decrypted = mdecrypt_generic($cipher, $value);
        mcrypt_generic_deinit($cipher);
        $this->_closeCipher($cipher);

        // decompress after decryption
        if (!empty($this->_compression)) {

            $decompress = new Zend_Filter_Decompress($this->_compression);
            $decrypted  = $decompress->filter($decrypted);
        }

        return $decrypted;
    }
public function decrypt($value)
    {
        $cipher = $this->_openCipher();
        $this->_initCipher($cipher);
        $decrypted = mdecrypt_generic($cipher, $value);
        mcrypt_generic_deinit($cipher);
        $this->_closeCipher($cipher);

        // decompress after decryption
        if (!empty($this->_compression)) {

            $decompress = new Zend_Filter_Decompress($this->_compression);
            $decrypted  = $decompress->filter($decrypted);
        }

        return $decrypted;
    }
Defined by Zend_Filter_Interface

Decrypts $value with the defined settings

@param  string $value Content to decrypt
@return string The decrypted content