Bar Code and QR code From Vf page to Email

Create a formula field in Contact object with any of the code(QR,Bar Code).  Before clicking on the email button in the vf page pass the id as the parameter in the url.

The formula would be

QR Code

IMAGE('https://chart.googleapis.com/chart?chs=150x150&cht=qr&chl=MECARD:N:' + FirstName + ' ' + LastName +';ADR:'+ MailingStreet +',' + MailingCity + ',' + MailingState + ',' + MailingCountry + ',' + MailingPostalCode + ';TEL:'+ MobilePhone +';EMAIL:' + Email + ';', 'Scan the QR code' )

Bar Code

IMAGE("http://www.barcodesinc.com/generator/image.php?code="+Id+"&style=325&type=C128B&width=200&height=50&xres=1&font=3" ,"Barcode")

Vf Page Code

<apex:page standardController="Contact" extensions="BarcodeController">

<apex:form >

<!-- <apex:inputField value="{!contact.QR_Code__c}"/>

<apex:inputField value="{!contact.Bar_Code__c}"/> -->

<apex:commandButton value="sendEmail" action="{!sendEmail}"/>

</apex:form>

</apex:page>

Apex Controller

public class BarcodeController {
    public Contact cont;
    public Id contactId; 

    public BarcodeController(ApexPages.StandardController controller) {
        //cont=(Contact)controller.getRecord();
        contactId=controller.getId();
    }
    
    public void sendEmail(){
        if(contactId !=null || contactId != ''){
            Cont=[select Id,Bar_Code__c,Qr_Code__c from Contact where id = : contactId limit 1];
        }
        String email='xxx@gmail.com';
        Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
            mail.setToAddresses(new String[] { email });
            mail.setSubject('Bar Code and the Q.R Code Demo');
           
            String body = cont.Bar_Code__c+
                        +cont.Qr_Code__c;
            mail.setHtmlBody('Scan the Qr code and the Bar code'+body );
     
        // Send the email
        Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
    }

}