Enable WebRTC simulcast to improve video performance for applications built with the Amazon Chime SDK

Posted on: Jun 18, 2020

Starting today, you can use the Amazon Chime SDK for JavaScript to develop applications that automatically adapt to changing conditions to optimize the video experience for each meeting attendee. From the JavaScript SDK, you can now enable the simulcast feature, supported by the underlying WebRTC library. Once enabled, each client joining an Amazon Chime SDK meeting will automatically display the highest quality video available for its unique situation by considering network conditions and the total number and types of video streams being shared in the meeting. 

When preparing an application to connect to an Amazon Chime SDK meeting, you can enable simulcast in the MeetingSessionConfiguration object. With simulcast enabled, clients will upload multiple video streams from the same video source using different resolutions and bitrates up to 1280x720 and 1200 kbps. For clients displaying remote video tiles, the VideoAdaptiveProbePolicy chooses which stream to subscribe to factoring in downlink bandwidth, number of video streams shared in the meeting, and by prioritizing content share over webcam video streams. 

The Amazon Chime SDK is a set of real-time communications components that developers can use to quickly add audio calling, video calling, and screen sharing capabilities to their own web or mobile applications. Developers can leverage the same communication infrastructure and services that power Amazon Chime, an online meetings service from AWS, and deliver engaging experiences in their applications. To learn more about Amazon Chime see the following resources: