It may be desirable for the frontend to receive ancillary information
over the control channel.
Such information includes but is not limited to time code metas, support
for other metas (eg custom meta) might be implemented in the future, as
well as downstream events.
This patch implements a new info message, probes buffers that arrive at
nicesink to look up timecode metas and potentially forwards them to the
consumer when the `forward-metas` property is set appropriately.
Internally, a "dye" meta is used to trace the media identifier the
packet we are about to send over relates to, as rtpfunnel bundles all
packets together.
The example frontend code also gets a minor update and now logs info
messages to the console.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1749>
1c48d7065d was mistakenly merged too
early, and there were concerns about the implementation and API design:
The fact that the frontend had to expose a text area specifically for
sending over a mix matrix, and had to manually edit in floats into the
stringified JSON was suboptimal.
Said text area was always present even when remote control was not
enabled.
The sendControlRequest API was made more complex than needed by
accepting an optional stringifier callback.
This patch addresses all those concerns:
The deserialization code in webrtcsink is now made more clever and
robust by first having it pick a numerical type to coerce to when
deserializing arrays with numbers, then making sure it doesn't allow
mixed types in arrays (or arrays of arrays as those too must share
the same inner value type).
The frontend side simply sends over strings wrapped with a request
message envelope to the backend.
The request text area is only shown when remote control is enabled.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1725>
This is one example of how a consumer might send over custom upstream
event requests to the producer.
As webrtcsink will deserialize numbers in priority as integers, we need
a custom stringifying function to ensure members of the matrix array are
indeed serialized with the floating point.
An optional stringifier parameter is thus added to the
sendControlRequest API.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1711>
.. and deprecate data channel navigation in favor of it.
A new property, "enable-data-channel-control" is exposed, when set to
TRUE a control data channel is offered, over which can be sent typed
upstream events.
This means further upstream events will be usable, for now only
navigation and custom upstream events are handled.
In addition, send response messages to notify the consumer of whether
its requests have been handled.
In the future this can also be extended to allow the consumer to send
queries, or seek events ..
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1711>
This subproject adds a high-level web API compatible with GStreamer
webrtcsrc and webrtcsink elements and the corresponding signaling
server. It allows a perfect bidirectional communication between HTML5
WebRTC API and native GStreamer.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/946>
