dictionary is a data type used to describe the capabilities of an
in response to a call to the
static functions, both of which return an array of
object contains an array of objects conforming to
(each describing the capabilities of one codec) and an array of the supported
for that codec.
RTCRtpCodecCapabilityobjects, each describing one of the codecs supported by the
RTCRtpReceiver. There are some special entries in this array, described below in the section The codecs array .
RTCRtpHeaderExtensionCapabilitydictionary. Each object contains a single
uri, specifying the URI of the header extension, as described in RFC 5285 .
array is an array of objects conforming to the dictionary
. Each of these objects describes a single codec and its basic capabilities. Its properties are:
The browser will only report distinct capability combinations separately. If two sets of capabilities can be described as one, they will be. That means that, for instance, if there are two entries for the H.264 codec (as identified by the
being "video/H264"), there are other values in the capabilities objects indicating how they're different in some way.
The MIME type strings used by RTP differ from those used elsewhere. See RFC 3555, section 4 for the complete IANA registry of these types.
There are three special entries that should always be present, representing underlying components of the transport. Those components are:
video/fwdred. The base RED standard can be found in RFC 2198 . There may be multiple entries for RED if different forms are supported; each will have a unique media type in that case.
fec. One possible value is
video/ulpfec(a generic error connection model). There may also be multiple FEC entries if more than one form is supported.
video/rtx. There will only be one entry for RTX, and it will not have an
Don't be surprised to see these show up ijn the list; be prepared to ignore them if you're only interested in the actual codecs used for the media itself.
WebRTC 1.0: Real-time Communication Between Browsers
The definition of 'RTCRtpCapabilities' in that specification.
No compatibility data found. Please contribute data for "api.RTCRtpCapabilities" (depth: 1) to the MDN 兼容性数据存储库 .