PLI stands for Picture Loss Indication. It is one of the error resiliency mechanisms in WebRTC.

A PLI can be sent when the receiver of the media lost a full frame or more. It is sent over RTCP.

A receiver of this message can decide to resent a full frame if he has one available in cache and finds it usable.

This message is similar to a FIR message but a bit more lenient in its heuristic.

About WebRTC Glossary

The WebRTC Glossary is an ongoing project where users can learn more about WebRTC related terms. It is maintained by Tsahi Levent-Levi of BlogGeek.me.

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