Media mix wiring protocol for media control

Protocol architecture for wiring media streams and specifying mixing behavior in a multipoint control unit. The protocol provides the capability to expose the core mixing algorithms to modification for mixing media without dealing with the functionality of the mixer itself (e.g., ports and IP specifics). The protocol facilitates the wiring of input media streams to output media streams by changing the mixing behavior via changes to the mixing algorithms using the protocol. The protocol operates based on a schema that includes controls related to route, wire, and filter for the mixer input and mixer output.

BACKGROUND

As more conferencing systems begin to offer one or more streams of the same media type (e.g., video), conferencing clients need to be capable of rendering more than one stream as offered by the conferencing systems in an inter-operable manner. Mechanisms such as grouping of SDP (session description protocol, as described in RFC 4566) media lines and SDP media content further help in achieving this goal. However, unless a conferencing client understands the context of how these streams ought to be rendered, the conferencing clients may not be able to render streams of which the client not aware.

Conventional multipoint control unit (MCU) architecture lack of an efficient, flexible protocol to modify the media mix in the mixer of the MCU such that entities can transmit media as specified or receive media as specified over time. One working group is working on solving the above deficiency by controlling the functions of a mixer (e.g., “play a prompt”, “expect DTMF”, “play this media”, etc.). However, the attempts to control or imitate functions of the mixer are then limited to the available functionality.

SUMMARY

The disclosed architecture provides an efficient and flexible protocol for wiring media streams and specifying mixing behavior in the multipoint control unit (MCU). Accordingly, entities can transmit media as specified or receive media as specified over time. The protocol provides the capability to expose the core algorithm to modification for mixing media without dealing with the functionality of the mixer itself.

The protocol facilitates media wiring by specifying: a means for uniquely identifying a media stream sent to an entity or received from an entity; a means for an entity to wire a media stream coming from the mixer to contain a mix of other specified streams that have been sent to the mixer (by other identities) without having to deal with ports and other IP-specifics; a means for an entity to wire a media stream sent to the mixer to appear in specific streams sent from the mixer (sent to other identities); a means to communicate the wiring of the various media streams to participants allowed to view the wiring based on local policy of the mixer; and, a means where the conference leader can change the main participant mix to include a stream from another entity (participant), and all participants in the conference can perceive the identity of the other entity.

To the accomplishment of the foregoing and related ends, certain illustrative aspects are described herein in connection with the following description and the annexed drawings. These aspects are indicative, however, of but a few of the various ways in which the principles disclosed herein can be employed and is intended to include all such aspects and equivalents. Other advantages and novel features will become apparent from the following detailed description when considered in conjunction with the drawings.

DETAILED DESCRIPTION

The disclosed architecture provides a protocol for accessing and manipulating the core mixing algorithms of media mixers, for example, a multipoint control unit (MCU). This also applies to a client-based implementation, rather than network-based implementations, where the user can manipulate the core mixing of audio and video at the client level.

FIG. 1illustrates a computer-implemented media control system100for modifying mixing algorithm behavior. The system100includes one or more mixing algorithms102of a media mixer104for mixing input media streams106according to one or more mixing behaviors108. The mixer104is a logical entity receives the set of media streams of the same type (e.g., audio), combines the media in a type-specific manner, and redistributes the result to a single output or multiple outputs (e.g., session participant(s)). The system100also includes a protocol interface110that includes one or more instructions112for modifying the mixing behavior108of the mixing algorithm(s)102to wire the input media streams106to produce one or more specific output media streams114.

The one or more instructions112of the protocol interface110facilitate modification of the mixing algorithms102to effect the mixing behavior(s)108to uniquely identify a media stream sent to an entity or to uniquely identify a media stream received from the entity, to wire the input media streams to the media mixer into the specific output stream exclusive of mixer port or IP management functions, and to expose wiring information to an entity based on a policy. The policy can be an enterprise policy created and imposed by an administrator, for example.

The one or more instructions112of the protocol interface110also facilitate changing in participation of a session by participants by deleting at least one of many main participants from the session or adding a new participant to the session. The protocol interface110includes one or more instructions112for notifying the main participants of the change in participation to the session. For example, if main participants A, B and C are in a conference, and participant A has requested to view participant B's video stream, participant C is not allowed to know that participant A is watching participant B. However, participant B can be allowed to know that participant A is watching participant B's media stream. The protocol interface110includes one or more instructions112for adding an input media stream of a new participant to the session and for presenting entity information of the new participant to the main participants.

In one implementation, the protocol interface110includes a new set of instructions for interacting with the mixing algorithms102to generate the mixing behavior(s)108. In an alternative implementation, the one or more instructions112include extensions to the existing set of controls for generate the mixing behavior(s)108. The new set of instructions and/or the control extensions are based on a schema that includes one or more schema elements of route, wire, and filter.

FIG. 2illustrates a media system200where a media control unit202includes a media mixer component204for mixing input streams based on changes to core mixing algorithms. Here, the media mixer component204includes two mixers: a first mixer206for receiving a first type of input media stream(s)208(e.g., audio) for wiring (or routing) to an output media stream210of the same type, and a second mixer212for receiving a second type of input media stream(s)214(e.g., video) for wiring (or routing) to an output media stream216of the same type. The first media mixer206includes a first mixing algorithm218for generating a first mixing behavior220.

A user can manipulate the first mixing algorithm218to change the first mixing behavior220via the protocol interface110when communicating one or more of the instructions112to the first mixing algorithm218of the first media mixer206. Similarly, the second media mixer212includes a second mixing algorithm222for generating a second mixing behavior224. The user can manipulate the second mixing algorithm222to change the second mixing behavior224via the protocol interface110when communicating one or more of the instructions112to the second mixing algorithm222of the second media mixer212.

The one or more instructions112facilitate modification of the mixing algorithms102to wire the input streams (208and214) as desired. The one or more instructions112manage the mixing behavior(s) (220and224) to uniquely identify a media stream sent to an entity or to uniquely identify a media stream received from the entity, to wire the input media streams to the media mixer into the specific output stream exclusive of mixer port or IP management functions, and to expose wiring information to an entity based on a policy.

The system200facilitates wiring of a single input stream (e.g., of stream(s)208and214) from point to point, from point to multiple points, multiple points to multiple points, and from multiple points to a single point. The system200can be employed as a network node (e.g., a server) and/or as a client on a client computing system, for example.

FIG. 3illustrates an alternative system300for modifying mixing algorithm behavior. The system300includes a media control unit302having a media mixer304from receiving an input media stream306, and routing the input stream306to an output media stream308in accordance with modified mixing behaviors. More specifically, the media mixer304includes an audio mixing algorithm310for mixing audio into the input stream306, and a video mixing algorithm312for mixing video into the input media stream306. The media mixer304includes the protocol interface110for processing the protocol instructions112from a management interface314. In other words, a user can interact via the management interface314to send one or more instructions112via the protocol interface110to modify the core audio mixing algorithm310and/or the core video mixing algorithm312.

The mixing algorithms (310and312) generate mixing behaviors that are processed by a routing component316for routing the input media stream306to the output media stream308. The routing component316receives and processes an audio mixing behavior318generated from the audio mixing algorithm310and a video mixing behavior320from the video mixing algorithm312. In other words, the input media stream306can be mixed with audio and/or video signals for routing as a mixed output media stream308to an output entity.

A policy component322receives and processes one or more policies that can regulate how the mixing is to be done and if the mixing will be performed based on the receiving entity, source users, etc. The policy component322can include a session policy server that governs the operation of the session.

FIG. 4illustrates the exemplary mixer104for wiring input streams to output streams at the mixing algorithm level. The mixer104receives input (or to-mixer) media streams400, and mixes the input streams400according to the video mixing algorithm310and the audio mixing algorithm320to produce output (or from-mixer) media streams402. Modification of the mixing algorithms (310and320) can occur via the protocol interface110.

The input streams400can be identified with identity information for the user and the type of media stream, for example, a user identity (userID=xx) and a media stream identity (ID=xx). In this example, input media stream types ID=30, ID=31, and ID=32 and userID=2 can be for a second session participant's (or endpoint) main audio stream, main video stream, and secondary video stream, respectively. Similarly, input media stream types ID=24 and ID=31 are associated with userID=3 for a third session participant's (or endpoint) main audio stream and main video stream, respectively. Other input streams400can be part of the conference session.

A “label” parameter identifies the media stream to and from the mixer104. As indicated previously, the input streams400to the mixer104(from a specific user and endpoint) are identified by an ID in the conferencing data model. The label is unique throughout the conferencing data model. The ID is unique within the endpoint media element in the data model and is generated by the conferencing server.

Consider that the label=10 is the stream containing the audio stream mix from all audio input streams offered to every session participant, label=11 includes a video mix, and that label=12 is an alternate mix of the video streams that is voice activated. The mixer104mixes the incoming video streams400from the participants into both the label=11 and label=12 output streams. This is one example of a mixer model; other mixer models can interpret the input streams differently. However, the introduction of the protocol interface110facilitates modification of the mixing algorithms in accordance with the disclosed architecture. The protocol interface110can receive change or modifications to the mixing algorithms (310and320) via XML, for example, and/or CCCP (centralized conference control protocol) commands.

FIG. 5illustrates an exemplary schema definition500for a protocol that can access and modify mixing behavior at the core mixing algorithms. The schema definition500can be as follows. In one implementation, the schema defines new controls extensions (e.g., route, wire and filter) from controls that are defined in a centralized conferencing (XCON) data model. The newly-added elements to the schema definition500are referenced in the following tree view with a “##” and circumscribed as502for the input to the mixer and504as the output of the mixer.

Following are a series of examples that illustrate ways in which the protocol architecture facilitates media wiring. The data contained within such a schema is shown in the following example. Consider a conference session with the media state as follows for a conference sip:conf233@example.com hosted on the MCU https://Mcu55.company.com:444/MCU.

Following is an example of CCCP command(s) for modifying the media route for a participant. Consider that the entity sip:foo@example.com wants to modify the media route based on the stream. The entity may do so by issuing the following CCCP command “modifyEndpointMedia”. The following example shows a request that foo@example.com is making to receive streams from bar1@contoso.com and bar2@fabrikam.com. (The XMLNS specification is omitted for readability.)

The response can be as follows:

The new state of the conference session (a media route for a participant) can be communicated to other participants in the conference using the state notification as shown below or can be polled using a new CCCP command. Following is an example of a notification option.

With respect to the polling-option, if there are size considerations with the previous notification-option and/or there is no capability for the system to filter out elements that require privacy functions, a polling mechanism can be used to retrieve the wire route. The mechanism returns a list of users and endpoints (session participants) that are watching a specific endpoint stream. The example below illustrates a command that can be used to retrieve media watcher state for bar1@contoso.com and endpoint sip:bar1@contoso.com;gr=4940254792 with media id=56. Since foo@example.com is the only entity watching the stream, that user entity and endpoint information is returned.

The response can be as follows:

Following is exemplary CCCP command for modifying the main media route effecting the session mix of participants.

The response can be as follows:

Following is an example of notification of the main media route. The new state of the conference can be communicated to other participants in the conference session using the state notification as shown below.

With respect to privacy concerns, the protocol instructions can communicate how the media is wired to other participants in the conference based on local policy. Local conference server policy can be taken into consideration whether the participant receiving this information is authorized to receive the wired media or not.

To accommodate the notification option, the Notifier (defined in RFC 3265 and RFC 4353 as a user agent that generates Notify requests for the purpose of notifying subscribers of the state of a resource) filters certain elements based on where the notification is being sent. If there are no privacy considerations, the Notifier can send this information to all participants or may choose to not send the information at all.

FIG. 6illustrates a method of managing media streams. At600, an input media stream of a conferencing session is wired to an endpoint according to a mixing behavior defined by a mixing algorithm. At602, the mixing algorithm is accessed using a protocol of instructions. At604, the mixing algorithm is changed using the protocol to rewire the input media stream according to a new mixing behavior.

FIG. 7illustrates a method of manipulating core mixing algorithms of a media mixer to rewire session media streams. At700, the core mixing algorithm(s) can be accessed using a protocol. At702, the input stream sent to an endpoint or received from an endpoint can be uniquely identified using the protocol. At704, optionally, specify rewiring of the input media stream of an endpoint at an output to include a mix of other input streams by other endpoints exclusive of functions related to ports and IP data using the protocol. At706, optionally, specify wiring of the input media stream of an endpoint to specific output media streams of corresponding endpoints using the protocol.

FIG. 8illustrates a method of manipulating core mixing algorithms of a media mixer to rewire session media streams. At800, the core mixing algorithm(s) can be accessed using a protocol. At802, communication of the wiring to session participants is specified using the protocol. At804, communication of the wiring is specified to session participants using the protocol and based on a session policy. At806, a change in participant mix of the conferencing session by a session leader is specified using the protocol.

Referring now toFIG. 9, there is illustrated a block diagram of a computing system900operable to execute media stream wiring at the core mixing algorithm level in accordance with the disclosed protocol architecture. In order to provide additional context for various aspects thereof,FIG. 9and the following discussion are intended to provide a brief, general description of a suitable computing system900in which the various aspects can be implemented. While the description above is in the general context of computer-executable instructions that may run on one or more computers, those skilled in the art will recognize that a novel embodiment also can be implemented in combination with other program modules and/or as a combination of hardware and software.

With reference again toFIG. 9, the exemplary computing system900for implementing various aspects includes a computer902having a processing unit904, a system memory906and a system bus908. The system bus908provides an interface for system components including, but not limited to, the system memory906to the processing unit904. The processing unit904can be any of various commercially available processors. Dual microprocessors and other multi-processor architectures may also be employed as the processing unit904.

The system bus908can be any of several types of bus structure that may further interconnect to a memory bus (with or without a memory controller), a peripheral bus, and a local bus using any of a variety of commercially available bus architectures. The system memory906can include non-volatile memory (NON-VOL)910and/or volatile memory912(e.g., random access memory (RAM)). A basic input/output system (BIOS) can be stored in the non-volatile memory910(e.g., ROM, EPROM, EEPROM, etc.), which BIOS are the basic routines that help to transfer information between elements within the computer902, such as during start-up. The volatile memory912can also include a high-speed RAM such as static RAM for caching data.

The computer902further includes an internal hard disk drive (HDD)914(e.g., EIDE, SATA), which internal HDD914may also be configured for external use in a suitable chassis, a magnetic floppy disk drive (FDD)916, (e.g., to read from or write to a removable diskette918) and an optical disk drive920, (e.g., reading a CD-ROM disk922or, to read from or write to other high capacity optical media such as a DVD). The HDD914, FDD916and optical disk drive920can be connected to the system bus908by a HDD interface924, an FDD interface926and an optical drive interface928, respectively. The HDD interface924for external drive implementations can include at least one or both of Universal Serial Bus (USB) and IEEE 1394 interface technologies.

A number of program modules can be stored in the drives and volatile memory912, including an operating system930, one or more application programs932, other program modules934, and program data936. The one or more application programs932, other program modules934, and program data936can include the mixing algorithms102, media mixer104, input media streams106, mixing behaviors108, protocol interface110, protocol instructions112, output media streams114, audio mixing algorithm310, video mixing algorithm320, input media streams400output media streams402, and the schema500, for example.

All or portions of the operating system, applications, modules, and/or data can also be cached in the volatile memory912. It is to be appreciated that the disclosed architecture can be implemented with various commercially available operating systems or combinations of operating systems.

A user can enter commands and information into the computer902through one or more wire/wireless input devices, for example, a keyboard938and a pointing device, such as a mouse940. Other input devices (not shown) may include a microphone, an IR remote control, a joystick, a game pad, a stylus pen, touch screen, or the like. These and other input devices are often connected to the processing unit904through an input device interface942that is coupled to the system bus908, but can be connected by other interfaces such as a parallel port, IEEE 1394 serial port, a game port, a USB port, an IR interface, etc.

A monitor944or other type of display device is also connected to the system bus908via an interface, such as a video adaptor946. In addition to the monitor944, a computer typically includes other peripheral output devices (not shown), such as speakers, printers, etc.

When used in a LAN networking environment, the computer902is connected to the LAN952through a wire and/or wireless communication network interface or adaptor956. The adaptor956can facilitate wire and/or wireless communications to the LAN952, which may also include a wireless access point disposed thereon for communicating with the wireless functionality of the adaptor956.

When used in a WAN networking environment, the computer902can include a modem958, or is connected to a communications server on the WAN954, or has other means for establishing communications over the WAN954, such as by way of the Internet. The modem958, which can be internal or external and a wire and/or wireless device, is connected to the system bus908via the input device interface942. In a networked environment, program modules depicted relative to the computer902, or portions thereof, can be stored in the remote memory/storage device950. It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers can be used.

Referring now toFIG. 10, there is illustrated a schematic block diagram of an exemplary client-server computing environment1000for accessing core mixing algorithms using an access protocol. The environment1000includes one or more client(s)1002. The client(s)1002can be hardware and/or software (e.g., threads, processes, computing devices). The client(s)1002can house cookie(s) and/or associated contextual information, for example.

The environment1000also includes one or more server(s)1004. The server(s)1004can also be hardware and/or software (e.g., threads, processes, computing devices). The servers1004can house threads to perform transformations by employing the architecture, for example. One possible communication between a client1002and a server1004can be in the form of a data packet adapted to be transmitted between two or more computer processes. The data packet may include a cookie and/or associated contextual information, for example. The environment1000includes a communication framework1006(e.g., a global communication network such as the Internet) that can be employed to facilitate communications between the client(s)1002and the server(s)1004.

Communications can be facilitated via a wire (including optical fiber) and/or wireless technology. The client(s)1002are operatively connected to one or more client data store(s)1008that can be employed to store information local to the client(s)1002(e.g., cookie(s) and/or associated contextual information). Similarly, the server(s)1004are operatively connected to one or more server data store(s)1010that can be employed to store information local to the servers1004.

The server(s)1004can include the mixing algorithms102, media mixer104, input media streams106, mixing behaviors108, protocol interface110, protocol instructions112, output media streams114, media control unit202, media mixer component204, media mixers (206and212), mixing algorithms (218and222) and corresponding mixing behaviors (220and224), audio mixing algorithm310, video mixing algorithm320, input media streams400output media streams402, and the schema500, for example. The clients(s)1002can also include some or all of the entities described for the server(s)1004, except the MCU, which is typically a network-based entity.