Interface MediaElement

  • All Superinterfaces:
    KurentoObject, MediaObject
    All Known Subinterfaces:
    BaseRtpEndpoint, Endpoint, FaceOverlayFilter, Filter, GenericMediaElement, GStreamerFilter, HttpEndpoint, HttpPostEndpoint, HubPort, ImageOverlayFilter, OpenCVFilter, PassThrough, PlayerEndpoint, RecorderEndpoint, RtpEndpoint, SdpEndpoint, SessionEndpoint, UriEndpoint, WebRtcEndpoint, ZBarFilter

    public interface MediaElement
    extends MediaObject
    The basic building block of the media server, that can be interconnected inside a pipeline.

    A MediaElement is a module that encapsulates a specific media capability, and that is able to exchange media with other MediaElements through an internal element called pad.

    A pad can be defined as an input or output interface. Input pads are called sinks, and it's where the media elements receive media from other media elements. Output interfaces are called sources, and it's the pad used by the media element to feed media to other media elements. There can be only one sink pad per media element. On the other hand, the number of source pads is unconstrained. This means that a certain media element can receive media only from one element at a time, while it can send media to many others. Pads are created on demand, when the connect method is invoked. When two media elements are connected, one media pad is created for each type of media connected. For example, if you connect AUDIO and VIDEO between two media elements, each one will need to create two new pads: one for AUDIO and one for VIDEO.

    When media elements are connected, it can be the case that the encoding required in both input and output pads is not the same, and thus it needs to be transcoded. This is something that is handled transparently by the MediaElement internals, but such transcoding has a toll in the form of a higher CPU load, so connecting MediaElements that need media encoded in different formats is something to consider as a high load operation. The event `MediaTranscodingStateChanged` allows to inform the client application of whether media transcoding is being enabled or not inside any MediaElement object.

    • Method Detail

      • getEncoderBitrate

        int getEncoderBitrate()
        Get Target video bitrate for media transcoding.

        The bitrate of a video has a direct impact on its perceived image quality. Higher bitrate means higher quality, but also a larger amount of bytes to transmit or store. Use this parameter to set the desired average bitrate in videos that are transcoded by the media server.

        This parameter is most useful for :rom:cls:`RecorderEndpoint` and :rom:cls:`RtpEndpoint`: when media is being transcoded (either for streaming or storing on disk), the resulting quality is directly controlled with this value.

        For :rom:cls:`WebRtcEndpoint`, this value should be left as default, as remote WebRTC receivers will already send feedback to inform the media server about what is the optimal bitrate to send.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 300000 (300 kbps).
      • getEncoderBitrate

        void getEncoderBitrate​(Continuation<Integer> cont)
        Get Target video bitrate for media transcoding.

        The bitrate of a video has a direct impact on its perceived image quality. Higher bitrate means higher quality, but also a larger amount of bytes to transmit or store. Use this parameter to set the desired average bitrate in videos that are transcoded by the media server.

        This parameter is most useful for :rom:cls:`RecorderEndpoint` and :rom:cls:`RtpEndpoint`: when media is being transcoded (either for streaming or storing on disk), the resulting quality is directly controlled with this value.

        For :rom:cls:`WebRtcEndpoint`, this value should be left as default, as remote WebRTC receivers will already send feedback to inform the media server about what is the optimal bitrate to send.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 300000 (300 kbps).
      • getEncoderBitrate

        TFuture<Integer> getEncoderBitrate​(Transaction tx)
        Get Target video bitrate for media transcoding.

        The bitrate of a video has a direct impact on its perceived image quality. Higher bitrate means higher quality, but also a larger amount of bytes to transmit or store. Use this parameter to set the desired average bitrate in videos that are transcoded by the media server.

        This parameter is most useful for :rom:cls:`RecorderEndpoint` and :rom:cls:`RtpEndpoint`: when media is being transcoded (either for streaming or storing on disk), the resulting quality is directly controlled with this value.

        For :rom:cls:`WebRtcEndpoint`, this value should be left as default, as remote WebRTC receivers will already send feedback to inform the media server about what is the optimal bitrate to send.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 300000 (300 kbps).
      • setEncoderBitrate

        void setEncoderBitrate​(int encoderBitrate)
        Set Target video bitrate for media transcoding.

        The bitrate of a video has a direct impact on its perceived image quality. Higher bitrate means higher quality, but also a larger amount of bytes to transmit or store. Use this parameter to set the desired average bitrate in videos that are transcoded by the media server.

        This parameter is most useful for :rom:cls:`RecorderEndpoint` and :rom:cls:`RtpEndpoint`: when media is being transcoded (either for streaming or storing on disk), the resulting quality is directly controlled with this value.

        For :rom:cls:`WebRtcEndpoint`, this value should be left as default, as remote WebRTC receivers will already send feedback to inform the media server about what is the optimal bitrate to send.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 300000 (300 kbps).
      • setEncoderBitrate

        void setEncoderBitrate​(int encoderBitrate,
                               Continuation<Void> cont)
        Set Target video bitrate for media transcoding.

        The bitrate of a video has a direct impact on its perceived image quality. Higher bitrate means higher quality, but also a larger amount of bytes to transmit or store. Use this parameter to set the desired average bitrate in videos that are transcoded by the media server.

        This parameter is most useful for :rom:cls:`RecorderEndpoint` and :rom:cls:`RtpEndpoint`: when media is being transcoded (either for streaming or storing on disk), the resulting quality is directly controlled with this value.

        For :rom:cls:`WebRtcEndpoint`, this value should be left as default, as remote WebRTC receivers will already send feedback to inform the media server about what is the optimal bitrate to send.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 300000 (300 kbps).
      • setEncoderBitrate

        void setEncoderBitrate​(int encoderBitrate,
                               Transaction tx)
        Set Target video bitrate for media transcoding.

        The bitrate of a video has a direct impact on its perceived image quality. Higher bitrate means higher quality, but also a larger amount of bytes to transmit or store. Use this parameter to set the desired average bitrate in videos that are transcoded by the media server.

        This parameter is most useful for :rom:cls:`RecorderEndpoint` and :rom:cls:`RtpEndpoint`: when media is being transcoded (either for streaming or storing on disk), the resulting quality is directly controlled with this value.

        For :rom:cls:`WebRtcEndpoint`, this value should be left as default, as remote WebRTC receivers will already send feedback to inform the media server about what is the optimal bitrate to send.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 300000 (300 kbps).
      • getMinEncoderBitrate

        int getMinEncoderBitrate()
        Get Minimum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to force a higher bitrate than what is being requested by receivers.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
      • getMinEncoderBitrate

        void getMinEncoderBitrate​(Continuation<Integer> cont)
        Get Minimum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to force a higher bitrate than what is being requested by receivers.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
      • getMinEncoderBitrate

        TFuture<Integer> getMinEncoderBitrate​(Transaction tx)
        Get Minimum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to force a higher bitrate than what is being requested by receivers.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
      • setMinEncoderBitrate

        void setMinEncoderBitrate​(int minEncoderBitrate)
        Set Minimum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to force a higher bitrate than what is being requested by receivers.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
      • setMinEncoderBitrate

        void setMinEncoderBitrate​(int minEncoderBitrate,
                                  Continuation<Void> cont)
        Set Minimum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to force a higher bitrate than what is being requested by receivers.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
      • setMinEncoderBitrate

        void setMinEncoderBitrate​(int minEncoderBitrate,
                                  Transaction tx)
        Set Minimum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to force a higher bitrate than what is being requested by receivers.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
      • getMaxEncoderBitrate

        int getMaxEncoderBitrate()
        Get Maximum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
        • 0 = unlimited. Encoding performed with bitrate as requested by receivers.
      • getMaxEncoderBitrate

        void getMaxEncoderBitrate​(Continuation<Integer> cont)
        Get Maximum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
        • 0 = unlimited. Encoding performed with bitrate as requested by receivers.
      • getMaxEncoderBitrate

        TFuture<Integer> getMaxEncoderBitrate​(Transaction tx)
        Get Maximum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
        • 0 = unlimited. Encoding performed with bitrate as requested by receivers.
      • setMaxEncoderBitrate

        void setMaxEncoderBitrate​(int maxEncoderBitrate)
        Set Maximum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
        • 0 = unlimited. Encoding performed with bitrate as requested by receivers.
      • setMaxEncoderBitrate

        void setMaxEncoderBitrate​(int maxEncoderBitrate,
                                  Continuation<Void> cont)
        Set Maximum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
        • 0 = unlimited. Encoding performed with bitrate as requested by receivers.
      • setMaxEncoderBitrate

        void setMaxEncoderBitrate​(int maxEncoderBitrate,
                                  Transaction tx)
        Set Maximum video bitrate for media transcoding.

        This parameter can be used to fine tune the automatic bitrate selection that normally takes place within elements that are able to dynamically change the encoding bitrate according to the conditions of the streaming, such as :rom:cls:`WebRtcEndpoint`.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        This should be left as default in most cases, given that remote WebRTC receivers already send feedback to inform the media server about what is the optimal bitrate to send. Otherwise, this parameter could be used for example to limit the total bitrate that is handled by the server, by setting a low maximum output for all endpoints.

        Setting a value will only work if done before the media starts to flow.

        • Unit: bps (bits per second).
        • Default: 0.
        • 0 = unlimited. Encoding performed with bitrate as requested by receivers.
      • getSourceConnections

        List<ElementConnectionData> getSourceConnections​(MediaType mediaType,
                                                         String description)
        Gets information about the sink pads of this media element.

        Since sink pads are the interface through which a media element gets it's media, whatever is connected to an element's sink pad is formally a source of media. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        description - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        Returns:
        A list of the connections information that are sending media to this element. The list will be empty if no sources are found. *
      • getSourceConnections

        TFuture<List<ElementConnectionData>> getSourceConnections​(Transaction tx,
                                                                  MediaType mediaType,
                                                                  String description)
        Gets information about the sink pads of this media element.

        Since sink pads are the interface through which a media element gets it's media, whatever is connected to an element's sink pad is formally a source of media. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        description - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        Returns:
        A list of the connections information that are sending media to this element. The list will be empty if no sources are found. *
      • getSinkConnections

        List<ElementConnectionData> getSinkConnections​(MediaType mediaType,
                                                       String description)
        Gets information about the source pads of this media element.

        Since source pads connect to other media element's sinks, this is formally the sink of media from the element's perspective. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        description - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        Returns:
        A list of the connections information that are receiving media from this element. The list will be empty if no sources are found. *
      • getSinkConnections

        TFuture<List<ElementConnectionData>> getSinkConnections​(Transaction tx,
                                                                MediaType mediaType,
                                                                String description)
        Gets information about the source pads of this media element.

        Since source pads connect to other media element's sinks, this is formally the sink of media from the element's perspective. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        description - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        Returns:
        A list of the connections information that are receiving media from this element. The list will be empty if no sources are found. *
      • connect

        void connect​(MediaElement sink,
                     MediaType mediaType,
                     String sourceMediaDescription,
                     String sinkMediaDescription)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        sinkMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • connect

        void connect​(Transaction tx,
                     MediaElement sink,
                     MediaType mediaType,
                     String sourceMediaDescription,
                     String sinkMediaDescription)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        sinkMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • disconnect

        void disconnect​(MediaElement sink,
                        MediaType mediaType,
                        String sourceMediaDescription,
                        String sinkMediaDescription)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        sinkMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • disconnect

        void disconnect​(Transaction tx,
                        MediaElement sink,
                        MediaType mediaType,
                        String sourceMediaDescription,
                        String sinkMediaDescription)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
        sinkMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • setAudioFormat

        void setAudioFormat​(AudioCaps caps)
        Set the type of data for the audio stream.

        MediaElements that do not support configuration of audio capabilities will throw a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR exception.

        NOTE: This method is not implemented yet by the Media Server to do anything useful.

        Parameters:
        caps - The format for the stream of audio
      • setAudioFormat

        void setAudioFormat​(Transaction tx,
                            AudioCaps caps)
        Set the type of data for the audio stream.

        MediaElements that do not support configuration of audio capabilities will throw a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR exception.

        NOTE: This method is not implemented yet by the Media Server to do anything useful.

        Parameters:
        caps - The format for the stream of audio
      • setVideoFormat

        void setVideoFormat​(VideoCaps caps)
        Set the type of data for the video stream.

        MediaElements that do not support configuration of video capabilities will throw a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR exception

        NOTE: This method is not implemented yet by the Media Server to do anything useful.

        Parameters:
        caps - The format for the stream of video
      • setVideoFormat

        void setVideoFormat​(Transaction tx,
                            VideoCaps caps)
        Set the type of data for the video stream.

        MediaElements that do not support configuration of video capabilities will throw a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR exception

        NOTE: This method is not implemented yet by the Media Server to do anything useful.

        Parameters:
        caps - The format for the stream of video
      • getGstreamerDot

        String getGstreamerDot​(GstreamerDotDetails details)
        Return a .dot file describing the topology of the media element.

        The element can be queried for certain type of data:

        • SHOW_ALL: default value
        • SHOW_CAPS_DETAILS
        • SHOW_FULL_PARAMS
        • SHOW_MEDIA_TYPE
        • SHOW_NON_DEFAULT_PARAMS
        • SHOW_STATES
        • SHOW_VERBOSE
        Parameters:
        details - Details of graph
        Returns:
        The dot graph. *
      • getGstreamerDot

        TFuture<String> getGstreamerDot​(Transaction tx,
                                        GstreamerDotDetails details)
        Return a .dot file describing the topology of the media element.

        The element can be queried for certain type of data:

        • SHOW_ALL: default value
        • SHOW_CAPS_DETAILS
        • SHOW_FULL_PARAMS
        • SHOW_MEDIA_TYPE
        • SHOW_NON_DEFAULT_PARAMS
        • SHOW_STATES
        • SHOW_VERBOSE
        Parameters:
        details - Details of graph
        Returns:
        The dot graph. *
      • getStats

        Map<String,​Stats> getStats​(MediaType mediaType)
        Gets the statistics related to an endpoint. If no media type is specified, it returns statistics for all available types.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        Delivers a successful result in the form of a RTC stats report. A RTC stats report represents a map between strings, identifying the inspected objects (RTCStats.id), and their corresponding RTCStats objects. *
      • getStats

        TFuture<Map<String,​Stats>> getStats​(Transaction tx,
                                                  MediaType mediaType)
        Gets the statistics related to an endpoint. If no media type is specified, it returns statistics for all available types.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        Delivers a successful result in the form of a RTC stats report. A RTC stats report represents a map between strings, identifying the inspected objects (RTCStats.id), and their corresponding RTCStats objects. *
      • isMediaFlowingIn

        boolean isMediaFlowingIn​(MediaType mediaType,
                                 String sinkMediaDescription)
        This method indicates whether the media element is receiving media of a certain type. The media sink pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        sinkMediaDescription - Description of the sink
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaFlowingIn

        TFuture<Boolean> isMediaFlowingIn​(Transaction tx,
                                          MediaType mediaType,
                                          String sinkMediaDescription)
        This method indicates whether the media element is receiving media of a certain type. The media sink pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        sinkMediaDescription - Description of the sink
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaFlowingOut

        boolean isMediaFlowingOut​(MediaType mediaType,
                                  String sourceMediaDescription)
        This method indicates whether the media element is emitting media of a certain type. The media source pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        sourceMediaDescription - Description of the source
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaFlowingOut

        TFuture<Boolean> isMediaFlowingOut​(Transaction tx,
                                           MediaType mediaType,
                                           String sourceMediaDescription)
        This method indicates whether the media element is emitting media of a certain type. The media source pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        sourceMediaDescription - Description of the source
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaTranscoding

        boolean isMediaTranscoding​(MediaType mediaType,
                                   String binName)
        Indicates whether this media element is actively transcoding between input and output pads. This operation is only supported for AUDIO and VIDEO media types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. The internal GStreamer processing bin can be indicated, if needed; if the bin doesn't exist, the return value will be FALSE.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        binName - Internal name of the processing bin, as previously given by MediaTranscodingStateChanged.
        Returns:
        TRUE if media is being transcoded, FALSE otherwise. *
      • isMediaTranscoding

        TFuture<Boolean> isMediaTranscoding​(Transaction tx,
                                            MediaType mediaType,
                                            String binName)
        Indicates whether this media element is actively transcoding between input and output pads. This operation is only supported for AUDIO and VIDEO media types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. The internal GStreamer processing bin can be indicated, if needed; if the bin doesn't exist, the return value will be FALSE.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        binName - Internal name of the processing bin, as previously given by MediaTranscodingStateChanged.
        Returns:
        TRUE if media is being transcoded, FALSE otherwise. *
      • getSourceConnections

        List<ElementConnectionData> getSourceConnections()
        Gets information about the sink pads of this media element.

        Since sink pads are the interface through which a media element gets it's media, whatever is connected to an element's sink pad is formally a source of media. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Returns:
        A list of the connections information that are sending media to this element. The list will be empty if no sources are found. *
      • getSourceConnections

        TFuture<List<ElementConnectionData>> getSourceConnections​(Transaction tx)
        Gets information about the sink pads of this media element.

        Since sink pads are the interface through which a media element gets it's media, whatever is connected to an element's sink pad is formally a source of media. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Returns:
        A list of the connections information that are sending media to this element. The list will be empty if no sources are found. *
      • getSourceConnections

        List<ElementConnectionData> getSourceConnections​(MediaType mediaType)
        Gets information about the sink pads of this media element.

        Since sink pads are the interface through which a media element gets it's media, whatever is connected to an element's sink pad is formally a source of media. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        Returns:
        A list of the connections information that are sending media to this element. The list will be empty if no sources are found. *
      • getSourceConnections

        TFuture<List<ElementConnectionData>> getSourceConnections​(Transaction tx,
                                                                  MediaType mediaType)
        Gets information about the sink pads of this media element.

        Since sink pads are the interface through which a media element gets it's media, whatever is connected to an element's sink pad is formally a source of media. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        Returns:
        A list of the connections information that are sending media to this element. The list will be empty if no sources are found. *
      • getSinkConnections

        List<ElementConnectionData> getSinkConnections()
        Gets information about the source pads of this media element.

        Since source pads connect to other media element's sinks, this is formally the sink of media from the element's perspective. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Returns:
        A list of the connections information that are receiving media from this element. The list will be empty if no sources are found. *
      • getSinkConnections

        TFuture<List<ElementConnectionData>> getSinkConnections​(Transaction tx)
        Gets information about the source pads of this media element.

        Since source pads connect to other media element's sinks, this is formally the sink of media from the element's perspective. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Returns:
        A list of the connections information that are receiving media from this element. The list will be empty if no sources are found. *
      • getSinkConnections

        List<ElementConnectionData> getSinkConnections​(MediaType mediaType)
        Gets information about the source pads of this media element.

        Since source pads connect to other media element's sinks, this is formally the sink of media from the element's perspective. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        Returns:
        A list of the connections information that are receiving media from this element. The list will be empty if no sources are found. *
      • getSinkConnections

        TFuture<List<ElementConnectionData>> getSinkConnections​(Transaction tx,
                                                                MediaType mediaType)
        Gets information about the source pads of this media element.

        Since source pads connect to other media element's sinks, this is formally the sink of media from the element's perspective. Media can be filtered by type, or by the description given to the pad though which both elements are connected.

        Parameters:
        mediaType - One of MediaType.AUDIO, MediaType.VIDEO or MediaType.DATA
        Returns:
        A list of the connections information that are receiving media from this element. The list will be empty if no sources are found. *
      • connect

        void connect​(MediaElement sink)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
      • connect

        void connect​(Transaction tx,
                     MediaElement sink)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
      • connect

        void connect​(MediaElement sink,
                     MediaType mediaType)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
        mediaType - the MediaType of the pads that will be connected
      • connect

        void connect​(Transaction tx,
                     MediaElement sink,
                     MediaType mediaType)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
        mediaType - the MediaType of the pads that will be connected
      • connect

        void connect​(MediaElement sink,
                     MediaType mediaType,
                     String sourceMediaDescription)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • connect

        void connect​(Transaction tx,
                     MediaElement sink,
                     MediaType mediaType,
                     String sourceMediaDescription)
        Connects two elements, with the media flowing from left to right.

        The element that invokes the connect will be the source of media, creating one sink pad for each type of media connected. The element given as parameter to the method will be the sink, and it will create one sink pad per media type connected.

        If otherwise not specified, all types of media are connected by default (AUDIO, VIDEO and DATA). It is recommended to connect the specific types of media if not all of them will be used. For this purpose, the connect method can be invoked more than once on the same two elements, but with different media types.

        The connection is unidirectional. If a bidirectional connection is desired, the position of the media elements must be inverted. For instance, webrtc1.connect(webrtc2) is connecting webrtc1 as source of webrtc2. In order to create a WebRTC one-2one conversation, the user would need to specify the connection on the other direction with webrtc2.connect(webrtc1).

        Even though one media element can have one sink pad per type of media, only one media element can be connected to another at a given time. If a media element is connected to another, the former will become the source of the sink media element, regardless whether there was another element connected or not.

        Parameters:
        sink - the target MediaElement that will receive media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • disconnect

        void disconnect​(MediaElement sink)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
      • disconnect

        void disconnect​(Transaction tx,
                        MediaElement sink)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
      • disconnect

        void disconnect​(MediaElement sink,
                        MediaType mediaType)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
        mediaType - the MediaType of the pads that will be connected
      • disconnect

        void disconnect​(Transaction tx,
                        MediaElement sink,
                        MediaType mediaType)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
        mediaType - the MediaType of the pads that will be connected
      • disconnect

        void disconnect​(MediaElement sink,
                        MediaType mediaType,
                        String sourceMediaDescription)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • disconnect

        void disconnect​(Transaction tx,
                        MediaElement sink,
                        MediaType mediaType,
                        String sourceMediaDescription)
        Disconnects two media elements. This will release the source pads of the source media element, and the sink pads of the sink media element.
        Parameters:
        sink - the target MediaElement that will stop receiving media
        mediaType - the MediaType of the pads that will be connected
        sourceMediaDescription - A textual description of the media source. Currently not used, aimed mainly for MediaType.DATA sources
      • getGstreamerDot

        String getGstreamerDot()
        Return a .dot file describing the topology of the media element.

        The element can be queried for certain type of data:

        • SHOW_ALL: default value
        • SHOW_CAPS_DETAILS
        • SHOW_FULL_PARAMS
        • SHOW_MEDIA_TYPE
        • SHOW_NON_DEFAULT_PARAMS
        • SHOW_STATES
        • SHOW_VERBOSE
        Returns:
        The dot graph. *
      • getGstreamerDot

        TFuture<String> getGstreamerDot​(Transaction tx)
        Return a .dot file describing the topology of the media element.

        The element can be queried for certain type of data:

        • SHOW_ALL: default value
        • SHOW_CAPS_DETAILS
        • SHOW_FULL_PARAMS
        • SHOW_MEDIA_TYPE
        • SHOW_NON_DEFAULT_PARAMS
        • SHOW_STATES
        • SHOW_VERBOSE
        Returns:
        The dot graph. *
      • getStats

        Map<String,​Stats> getStats()
        Gets the statistics related to an endpoint. If no media type is specified, it returns statistics for all available types.
        Returns:
        Delivers a successful result in the form of a RTC stats report. A RTC stats report represents a map between strings, identifying the inspected objects (RTCStats.id), and their corresponding RTCStats objects. *
      • getStats

        TFuture<Map<String,​Stats>> getStats​(Transaction tx)
        Gets the statistics related to an endpoint. If no media type is specified, it returns statistics for all available types.
        Returns:
        Delivers a successful result in the form of a RTC stats report. A RTC stats report represents a map between strings, identifying the inspected objects (RTCStats.id), and their corresponding RTCStats objects. *
      • isMediaFlowingIn

        boolean isMediaFlowingIn​(MediaType mediaType)
        This method indicates whether the media element is receiving media of a certain type. The media sink pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaFlowingIn

        TFuture<Boolean> isMediaFlowingIn​(Transaction tx,
                                          MediaType mediaType)
        This method indicates whether the media element is receiving media of a certain type. The media sink pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaFlowingOut

        boolean isMediaFlowingOut​(MediaType mediaType)
        This method indicates whether the media element is emitting media of a certain type. The media source pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaFlowingOut

        TFuture<Boolean> isMediaFlowingOut​(Transaction tx,
                                           MediaType mediaType)
        This method indicates whether the media element is emitting media of a certain type. The media source pad can be identified individually, if needed. It is only supported for AUDIO and VIDEO types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. If the pad indicated does not exist, if will return false.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        TRUE if there is media, FALSE in other case. *
      • isMediaTranscoding

        boolean isMediaTranscoding​(MediaType mediaType)
        Indicates whether this media element is actively transcoding between input and output pads. This operation is only supported for AUDIO and VIDEO media types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. The internal GStreamer processing bin can be indicated, if needed; if the bin doesn't exist, the return value will be FALSE.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        TRUE if media is being transcoded, FALSE otherwise. *
      • isMediaTranscoding

        TFuture<Boolean> isMediaTranscoding​(Transaction tx,
                                            MediaType mediaType)
        Indicates whether this media element is actively transcoding between input and output pads. This operation is only supported for AUDIO and VIDEO media types, raising a MEDIA_OBJECT_ILLEGAL_PARAM_ERROR otherwise. The internal GStreamer processing bin can be indicated, if needed; if the bin doesn't exist, the return value will be FALSE.
        Parameters:
        mediaType - One of MediaType.AUDIO or MediaType.VIDEO
        Returns:
        TRUE if media is being transcoded, FALSE otherwise. *
      • removeElementConnectedListener

        void removeElementConnectedListener​(ListenerSubscription listenerSubscription,
                                            Continuation<Void> cont)
        Remove a ListenerSubscription for event ElementConnectedEvent. Asynchronous call. Calls Continuation<Void> when it has been removed.
        Parameters:
        listenerSubscription - Listener subscription to be removed
        cont - Continuation to be called when the listener is removed
      • removeElementDisconnectedListener

        void removeElementDisconnectedListener​(ListenerSubscription listenerSubscription,
                                               Continuation<Void> cont)
        Remove a ListenerSubscription for event ElementDisconnectedEvent. Asynchronous call. Calls Continuation<Void> when it has been removed.
        Parameters:
        listenerSubscription - Listener subscription to be removed
        cont - Continuation to be called when the listener is removed
      • removeMediaFlowOutStateChangedListener

        void removeMediaFlowOutStateChangedListener​(ListenerSubscription listenerSubscription,
                                                    Continuation<Void> cont)
        Remove a ListenerSubscription for event MediaFlowOutStateChangedEvent. Asynchronous call. Calls Continuation<Void> when it has been removed.
        Parameters:
        listenerSubscription - Listener subscription to be removed
        cont - Continuation to be called when the listener is removed
      • removeMediaFlowInStateChangedListener

        void removeMediaFlowInStateChangedListener​(ListenerSubscription listenerSubscription,
                                                   Continuation<Void> cont)
        Remove a ListenerSubscription for event MediaFlowInStateChangedEvent. Asynchronous call. Calls Continuation<Void> when it has been removed.
        Parameters:
        listenerSubscription - Listener subscription to be removed
        cont - Continuation to be called when the listener is removed