How to auto login with an avatar ?

How to autologin into HTML5-chat with an user avatar ?

ex: we want to login as John, whose sex is male an whose avatar is external url: https://html5-chat.com/img/malecostume.svg

(let assume our script id is 1544 and token is 5a0440c6c992c)

<script src=’https://html5-chat.com/script/1544/5a0440c6c992c/John/couple/aHR0cHM6Ly9odG1sNS1jaGF0LmNvbS9pbWcvbWFsZWNvc3R1bWUuc3Zn‘></script>
This aHR0cHM6Ly9odG1sNS1jaGF0LmNvbS9pbWcvbWFsZWNvc3R1bWUuc3Zn represents the base64 url to our avatar:
in php we can use: base64_encode
<php $avatar = base64_encode(‘https://html5-chat.com/img/malecostume.svg’); ?>