WebRTC and Video Calling Applications

Lecture Overview

Presenter: Dennis Ivey

• Focus: Building two WebRTC applications: a peer-to-peer video calling app and a group video calling app using Agora.
• Important note: WebRTC enables peer-to-peer connections between browsers for real-time communication.

Project 1: Peer-to-Peer Video Call Application

Features

1. Lobby and Room Creation
   • Join a room using a room ID.
   • Invite another user into a room.
2. Video Call Functionalities
   • Muting microphone.
   • Toggling the camera.

Steps to Build

1. Project Setup
   • Create folder and files: index.html, main.css, main.js.
2. HTML Structure
   • Container for video elements and controls.
   • Two video tags for local and remote users.
3. CSS Styling
   • Grid layout for video containers.
   • Background colors and dimensions for video players.
4. JavaScript Functionality
   • Get user media for accessing the camera and microphone.
   • Create peer connection using WebRTC APIs.
   • Handle ICE candidates for establishing connections.
   • Implement functions to add local tracks, respond to remote track additions, and handle video call controls (mute, toggle, etc.).

Agora Integration

• Use Agora's SDK for signaling and real-time messaging.
• Process involves:
  • Creating an Agora account.
  • Setting up a new project in Agora console.
  • Downloading the SDK and integrating it into the project.
• Replace manual WebRTC signaling with Agora’s services.

Project 2: Group Video Call Application with Agora

Features

1. Group Video Chat Functionalities

   • Join/leave rooms with invite links.
   • Mute/unmute microphone and camera.
   • Share screen capability.
   • Real-time chat within the room.
   • View and switch between participants’ video frames.
   • Highlight a specific user’s video frame.

2. User Interface Customizations

   • Responsive design for different device sizes.
   • Dynamic element adjustments for participant video frames and controls.

Application Setup

1. Initial Template Setup
   • HTML structure for the user lobby and room pages.
   • CSS for styling components like video frames, participants list, and chatbox.
2. JavaScript Functionality
   • Manage Agora RTC and RTM clients.
   • Handle room initiation, joining, leaving, and real-time communication.
   • Implement screen sharing and toggling functionalities.
3. Enhancing User Experience
   • Add/remove DOM elements dynamically based on user interactions.
   • Update participants count and list in real-time.
   • Enable real-time messaging with smooth user notifications.
4. Implementing Real-Time Features
   • Use Agora RTM SDK for chat and participant updates.
   • Synchronize video streams, chat messages, and participant events to enhance collaboration.

Important Points

• Agora SDKs simplify complex WebRTC operations.
• Group video calls require efficient handling of numerous concurrent streams.
• User notifications help manage real-time interaction smoothly.

Summary

Both projects leverage WebRTC and Agora's services for reliable real-time communication. The peer-to-peer video call application focuses on direct browser-to-browser connections, while the group video call application uses Agora’s infrastructure to scale effectively, adding complexity yet offering a robust solution for multi-user video chatting and collaboration.