Introduction to WebRTC

WebRTC (Web-based Real Time Communications) is an open source video communication framework for web browsers. It was open sourced by Google Inc., on Jun 1, 2011, following the acquisition by Google of Global IP Solutions, whose code is largely in WebRTC. The objective of WebRTC open source project is to enable rich, high quality, real time communications in Web browsers via Java Script and HTML5. WebRTC consists of 3 major components, a voice engine, a video engine and transport (network I/O). For more detailed information please see www.webrtc.org.

Both the voice engine and transport of WebRTC are mature and well optimized technologies, as they have been in use by Global IP Solutions for many years. The video engine consists of only VP8 which is a relatively new video codec. Prior to acquisition by Google, Global IP Solutions used H.264 AVC and SVC codec developed by VSS. While WebRTC with VP8 video codec may satisfy web browser based real time communication systems, many video communication technology suppliers are interested in H.264 and HEVC based WebRTC. Majority of consumer and professional video communication devices rely on hardware encoder and decoder for its low latency and low power consumption as compared to PC software implementations. Vast majority of such hardware devices are based on H.264/AVC and SVC codecs and are likely to remain that way for the near future.

VSS has undertaken the task of enabling WebRTC framework with both software and hardware H.264/AVC and SVC video engines. With the emergence of HEVC standard, VSS will offer an HEVC based video engine for WebRTC as well. Enabling H.264 in WebRTC bring many benefits and challenges which VSS will address.

H.264/AVC and SVC based video engine in WebRTC will enable:

• Video communication in appliances like Consumer HDTV, network cameras, conference bridges, etc.
• Skype like pier to pier communication between PC, mobile and appliance devices
• WebRTC framework will provide interoperability between various implementations eliminating the need for proprietary communication servers
• H.264/SVC codec together with applicable transport will allow for fully scalable video communications between any variety of client end-points (PC, mobile or appliance devices).

WebRTC enabled H.264 video engine will have some challenges:

• RTC video engine requires a specialized and highly optimized CODEC which balances video quality with low latency of encode/decode. In addition, CODEC must be optimized for un-expected network packet loss and bandwidth fluctuations. VSS H.264/AVC and SVC codec fully satisfies these demanding requirements
• There are a multitude of PC, mobile and appliance devices in the market today which require video communications. Each has its own CPU/GPU capabilities and system restrictions.

VSS will overcome this challenge with a breadth of CODEC optimizations which will include:

• PC software only CODEC for Windows, Linux and Mac
• PC software with GPU accelerated CODEC for systems like Laptops and Netbooks
• ARM software and hybrid accelerated CODEC for smartphones and tables with Apple iOS and Android.
• FPGA IP Cores for enabling high performance, multichannel video communication device