WebRTC Metrics
A comprehensive overview of WebRTC statistics, derived calculations, extracted features, and observable signals, to better understand call quality, connectivity, and user experience in rtcStats
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codeccodecaudiovideoSDP
sdpFmtpLine
Last updated Applies toany rtcStats setup
The SDP format-specific parameters for this codec.
Description
String
The format-specific parameters from the "a=fmtp" line in SDP corresponding to this codec. Contains codec-specific configuration such as H.264 profile level, VP9 profile, or Opus settings like useinbandfec and usedtx.
See also
- codec->payloadType
- codec->mimeType
- WebRTC Statistics Specification
Notes
- For H.264, this typically includes "level-asymmetry-allowed=1;packetization-mode=1;profile-level-id=42e01f" indicating the profile and level
- For opus, parameters like "minptime=10;useinbandfec=1" control FEC and packet timing
- Empty or absent for codecs with no format parameters
