RTCCodecStats: sdpFmtpLine property

{{APIRef("WebRTC")}}

The sdpFmtpLine property of the {{domxref("RTCCodecStats")}} dictionary is a string containing the format-specific parameters of the codec.

These are the values in the "a=fmtp" line in the codec's {{Glossary("SDP")}} (if present) after the payload type number (see section 5.8 of the IETF specification for JSEP).

Values

A string containing the format-specific parameters of the codec.

Description

The "a=fmtp" line in the codec's {{Glossary("SDP")}} line has the following format, where the payload type (see {{domxref("RTCCodecStats.payloadType")}}) and parameters depend on the codec:

a=fmtp:<payload_type_number> param1=value1; ...; paramN=valueN

For example, the following line would indicate that the "opus" codec, which has a payloadType 99, has the format-specific parameters maxplaybackrate and stereo:

a=fmtp:99 maxplaybackrate=16000; stereo=1;

For this codec, the value in sdpFmtpLine would be maxplaybackrate=16000; stereo=1;.

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• codecs.sdpFmtpLine option in parameter passed to RTCRtpTransceiver.setCodecPreferences() and RTCRtpSender.setParameters().
• codecs.sdpFmtpLine in object returned by RTCRtpSender.getParameters() and RTCRtpReceiver.getParameters().