The Live Content Adaptation solution contains a WebRTC web player with adaptation of multiple real-time 2D video streams.
The Live Content Adaptation Algorithm for the TRACTION EU-project is used to select the appropriate video resolution and bitrates during live content streaming to guarantee viewers’ good QoE. The algorithm considers different network condition parameters such as bandwidth, packet loss, and jitter. Further, the algorithm tries to ensure the highest bitrate for audio, this is a key feature for performing and viewing opera arts pieces, while adapting the video quality given the bandwidth constraints. This is because many studies have shown that ensuring high audio quality can have a positive impact on viewers’ QoE.
The TRACTION Live Content Adaptation Algorithm is deployed with the WebRTC. The deployment was done using Janus WebRTC server. The algorithm is implemented in
/LiveContentAdaptation/src. The algorithm make use of the videoroom plugin of Janus. The file containing the algorithm’s logic is
To use the Live Content Adaptation Algorithm, first you need to setup a Janus WebRTC server. The Admin/Monitor APIs should be enabled at the Janus WebRTC server. To include the algorithm, make sure to add the janus.js, streamadapt.js, bandwidthhandler.js, and methods.js to the end of the body. A sample html file with single publisher stream is present in
Now, initialise the janus server name in the streamadapt.js. The janusServer and server attribute should contain the link to the janus server name and the port.
var janusServer = "dummy.janusserver.details"; var server = null; server = "wss://" + (janusServer || window.location.hostname) + ":8989/janus";
The janus sever API enables the collection of some network metrics such as:
var lostlocal = json["event"]["lost"]; var lostremote = json["event"]["lost-by-remote"]; var jitterlocal = json["event"]["jitter-local"]; var jitterremote = json["event"]["jitter-remote"]; var packetssent = json["event"]["packets-sent"]; var packetsrecv = json["event"]["packets-received"]; var bytessent = json["event"]["bytes-sent"]; var bytesrecv = json["event"]["bytes-received"]; var nackssent = json["event"]["nacks-sent"]; var nacksrecv = json["event"]["nacks-received"];
event denotes the different even types (i.e., session, media, SDP, WebRTC). These metrics along with others can help the adaptation algorithm.
To be able to add or modify the algorithm, you need to do the following steps:
git clone https://github.com/traction-project/LiveContentAdaptation.git).
janus.js, and related files.
npm run start).
Full Documentation is available describing all methods, interfaces, properties, and events.