In the snippet below it is shown how to show conversation video for specified TelephonyConversation through ConversationWindow.showForConversation method:
var conversationWindow;
var conversation
// ...
// Create conversation video window in designated html element.
// Obtain telephony conversation for which we want to show video.
// ...
conversationWindow.showForConversation();
var conversationWindow;
var conversation
// ...
// Create conversation video window in designated html element.
// Obtain telephony conversation for which we want to show video.
// ...
conversationWindow.hideForConversation();