Недостающий IMAP ошибка расширения PHP

Я перехожу по этой ссылке для установки Kaltura. Но я вкладываю проблему sudo php install.php шаг.

sneha@SCS-I82:~/Downloads/kalturaCE_v3.0.0-instructure$ sudo php install.php

Thank you for installing Kaltura Video Platform - Community Edition

A previous installation attempt has been detected, do you want to use the input you provided during you last installation? (Y/n)
> n

In order to improve Kaltura Community Edition, we would like your permission to send system data to Kaltura.
This information will be used exclusively for improving our software and our service quality. I agree (Y/n)
> Y

If you wish, please provide your email address so that we can offer you future assistance (leave empty to pass)
> sneha.kachroo@harbingergroup.com

PHP Notice:  Array to string conversion in /home/sneha/Downloads/kalturaCE_v3.0.0-instructure/installer/OsUtils.class.php on line 13
Please provide the following information:

The following apachectl script has been detected: /usr/sbin/apachectl. Do you want to use this script to run your Kaltura application? Leave empty to use or provide a pathname to an alternative apachectl script on your server.
> 

The following PHP binary has been detected: /usr/bin/php. Do you want to use this script to run your Kaltura application? Leave empty to use or provide a pathname to an alternative PHP binary on your server.
> 

Full target directory path for Kaltura application (leave empty for /opt/kaltura)
> 

Please enter the domain name/virtual hostname that will be used for the Kaltura server (without http://)
> kalturadev.example.com

Your primary system administrator email address
> sneha.kachroo@gmail.com

The password you want to set for your primary administrator
> India_4321

Database host (leave empty for 'localhost')
> 

Database port (leave empty for '3306')
> 

Database username (with create & write privileges)
> sneha

Database password (leave empty for no password)
> 

The URL to your xymon/hobbit monitoring location. Xymon is an optional installation. Leave empty to set manually later
Examples:
http://www.xymondomain.com/xymon/
http://www.xymondomain.com/hobbit/
> 


Verifing prerequisites

One or more prerequisites required to install Kaltura failed:
   Missing imap PHP extension
   Failed to connect to database 127.0.0.1:3306 user:sneha. Please check the database settings you provided and verify that MySQL is up and running.

Please resolve the issues and run the installation again.

Не получение, что Missing imap PHP extension ошибка о.