WO2007121629A1

WO2007121629A1 - Methods and systems for managing and controlling network-based content transformations (nbct) functionality in multimedia communication services

Info

Publication number: WO2007121629A1
Application number: PCT/CN2006/003340
Authority: WO
Inventors: Weijun Lee; Feng Zhang
Original assignee: Zte Corporation
Priority date: 2006-04-21
Filing date: 2006-12-08
Publication date: 2007-11-01
Also published as: CN101427547B; CN101427547A

Abstract

Disclosed is a system and method for implementing Network-Based Content Transformation (NBCT) in multimedia communication services. The system includes NBCT Media Server Functions, NBCT Database Function, NBCT Operator Portal Function, NBCT User Portal Function, NBCT Application Server Function, NBCT Charging Function, NBCT Operator Client Function, and NBCT User Client Function. The method comprises steps of creating a NBCT program to implement a content transformation; uploading the NBCT program into a NBCT Database Function (NDF); subscribing a user to a NBCT service; activating the NBCT for the user; and triggering the NBCT and applying to a selected media flow, when the user originates or terminates a multimedia call.

Description

Methods and Systems for Managing and Controlling Network-Based Content Transformations (NBCT) Functionality in Multimedia

Communication Services

FIELD OF THE INVENTION

The present invention relates to methods and systems for transforming the contents of the media flows in multimedia communication services. More specifically, the present invention relates to methods and systems for managing and controlling the Network-Based Content Transformations (NBCT) functionality to the contents of the multimedia flows in multimedia communication services.

BACKGROUND OF THE INVENTION A multimedia communication service involves both user terminals and various network devices. The media streams (e.g. video/audio/text), captured by a user terminal are transported to the remote user terminal(s) either directly without any changes or through some media-processing network devices, e.g. media gateways or media servers, to modify and match the encoding/decoding formats (codes).

However, no network devices today change the contents (i.e. visual and audio effects) of the media streams captured by a local user terminal, namely, the remote user always sees the same visual images, hear the same sounds, and read the same text as the local user. To overcome this limitation we propose an approach that is named as

Network-Based Content Transformations (NBCT). Some examples of content transformations are illustrated in Figure 1. The NBCT technology has many important applications: For example, NBCT may be used to protect user identity and privacy by masking out certain facial characteristics or by masking out the inconvenient surroundings of a conversation. NBCT is also an enabler for designing a wide variety of value-added services, e.g. adding funny facial masks or special sounds/tunes in a multimedia conversation for amusement. Yet another example usage of NBCT is to provide text-translation during a multimedia conversation.

In this patent application we disclose the systems and methods to perform and control Network-Based Content Transformations (NBCT) in multimedia communication services. Note that, in contrast to network-based content transformations, some user terminals (e.g. webcams) may internally perform certain content transformations (e.g. visual effects) to their locally captured video frames before sending them out to the network. This approach may be named as Terminal-Based Content Transformations (TBCT). The differences between NBCT and TBCT are illustrated in Figure 2. However, TBCT is not suitable for wide deployment because it cannot be applied to generic low-end multimedia user terminals, is hard for operators to manage the offered set of transformations, and cannot support lawful interception to the original media streams. On the other hand, the NBCT approach completely solves the above mentioned issues of TBCT and is well suited for wide deployment of multimedia communications services by telecom operators. •

SUMMARY OF THE INVENTION

The object of the present invention is to address two issues that exist today:

Lack of multimedia content transformation services provided by telecommunication networks today. - Scalability and manageability problems in current user terminal-based content transformation methods.

This invention discloses the systems and methods that provide Network-Based Content Transformation (NBCT) services to the contents of the media flows in a multimedia communication session.

This invention consists two parts: the architecture and functions of Network-Based Content Transformation (NBCT) systems, and the methods for managing and controlling NBCTs in a multimedia communication session. This invention discloses the architecture and logical functions of a

NBCT system, which consists of the following functions, as shown in Figure 3:

- NBCT Media Server Functions (NMSF) - NBCT Database Function (NDF)

- NBCT Operator Portal Function (NOPF)

- NBCT User Portal Function (NUPF)

- NBCT Application Server Function (NASF)

- NBCT Charging Function (NCF) - NBCT Operator Client Function (NOCF)

- NBCT User Client Function (NUCF)

The details of each function are described in the "Detailed Description of Preferred Embodiments" section.

Note these functions are logical functions and may optionally be combined into one or more physical devices in actual implementations.

This invention also discloses the methods of managing and controlling Network-Based Content Transformation services in a multimedia communication sessions, which include the following procedures:

- The overall procedure for NBCT deployment (and the state transition diagram of a NBCT) as shown in Figure 4. ^. - The procedures for the operator to manage NBCT database functions and user subscriptions.

- The procedures for a user to manage user subscriptions.

- The procedure to establish a NBCT service in a multimedia.

The details of each procedure are described in the "Detailed Description of Preferred Embodiments" section.

According to an aspect of the present invention, there is provided a system for implementing Network-Based Content Transformation (NBCT) in multimedia communication services. The system includes: a database function module for storing NBCT programs, and recording their status associated with different users; an operator portal function module for managing the NBCT programs and their status associated with different users; an or more operator client function modules for providing interfaces to communicate with the operator portal function module; a user portal function module for managing NBCT subscriptions and activations to users; . a or more user client function modules for providing user interfaces to communicate with the user portal function module; an application server function module for interacting with Call Server to set up a multimedia call based on a call set up message sent by a user terminal, and looking up the database function module to select the active NBCT programs applicable to the user; and _. a media server function module for loading the selected NBCT programs, under the controlling of the application server function module, allocating media processing resources and network resources, and returning network addresses of allocated media processing resources to receive one or more media flows from an original user terminal and send to a destination user terminal after performing the selected content transformations with the loaded NBCT programs.

Preferably, the application server function module is further for generating session detail records on usage of NBCT services and storing to the database function module; and the database function module is further for storing the NBCT usage data. .. ^' ,

Preferably, the system further comprises a charging function module for retrieving NBCT usage data from the database function module, and generating charging records according to operator-defined billing policies. Preferably, the database function module is further for managing uploads, downloads and updates of NBCT programs, managing user subscriptions to NBCTs, and managing user activations to subscribed NBCTs.

Preferably, the operator portal function module uploads NBCT programs created from the operator client function module to the database function module, and operates the NBCT programs according to requests of the operator client function module.

Preferably, the user portal function module updates the status of NBCT programs according to a user request of the user client function module. .

Preferably, the user portal function module is further for notifying the user client function module of new NBCT programs available for subscription.

Preferably, the user client function module is further for providing user interfaces to notify users of new NBCT programs available for subscription. ^' Preferably, the application server function module selects an active NBCT program according to a list of active NBCTs returned by the database function module and a type of the current media flow.

According to an aspect of the present invention, there is provided a method for implementing Network-Based Content Transformation (NBCT) in multimedia communication services. The method includes the steps of: creating one or more NBCT programs and storing to a database; subscribing one or more NBCT programs to one or more users; . activating one or more NBCT programs to one or more users; interacting with Call Server to set up a multimedia call based on a call set up message sent by a user, and looking up the database to select an active NBCT program applicable to the user; and loading the selected NBCT programs, allocating media processing resources and network resources, and returning addresses of allocated network resources to receive a media flow from an original user terminal and send to a destination user terminal after performing a content transformation based on the loaded NBCT program. Preferably, the method further comprises the step of generating session detail records on usage of NBCT services and storing to the database. . .

. Preferably, the method further comprises the step of retrieving NBCT usage data from the database, and generating charging records according to operator-defined billing policies. Preferably, the NBCT programs are subscribed according to a request of users, or an assignment of an operator.

Preferably, the NBCT programs are activated according to a request from a user, or an assignment from an operator.

Preferably, the database further manages uploads, downloads and updates of NBCT programs, user subscriptions to NBCTs, and user activations to subscribed NBCTs. Preferably, the NBCT programs are uploaded to the database, and controlled by an operator with client/server mode.

Preferably, the NBCT programs are subscribed or activated by a user with client/server mode.

Preferably, by the client/server mode, a user is notified that new NBCT programs available for subscription.

Preferably, the active NBCT programs are selected according to a query result to the subscriber database with a type of the current media flow, the originating user, and the destination user.

This invention fills a gap of the currently available telecommunication services. By providing systems and methods to support network-based content transformations in multimedia communication sessions, this invention enables a wide variety of new revenue-generating telecommunication services, including but not limited to: - Privacy protection to key user identities (e.g. eyes, faces)

- Privacy protection to inconvenient surrounding scenes in a conversation (e.g. background scenes, surrounding people)

- Funny facial masks for amusement

- Network-based Karaoke services ._. ^• . . ^•

Compared with user Terminal-Based Content Transformation (TBCT) ^• methods, the network-based content transformation (NBCT) methods disclosed in this invention have the following advantages:

- It enables content-transformation services to all types of multimedia user terminals, instead of only user terminals with TNCT functions

- The media processing resources for content transformations are shared among all users and dynamically allocated in each call, and thus is more economical than TBCT methods

- It ensures service ubiquity and consistency by allowing operators to offer the same set of content-transformations to all users, instead of terminal irregularities in TBCT methods - It is easier to add new content transformations than TBCT methods

^~ It is able to offer more transformations to end users since the network-side servers have much more powerful media processing resources than what is available inside each TBCT user terminal.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 gives some examples of content transformations to the video stream of a multimedia communication session.

Figure 2 illustrates the differences between Network-Based Content Transformation (NBCT) methods and Terminal-Based Content Transformation (TBCT) methods.

Figure 3 depicts the architecture and functions of a NBCT system, which consists of the NBCT Application Server Function (NASF), NBCT Media Server Functions (NMSF), NBCT Database Function (NDF), NBCT Operator Portal Function (NOPF), NBCT User Portal Function (NUPF), NBCT Charging Function (NCF), NBCT Operator Client Function (NOCF), and NBCT User Client Function (NUCF).

Figure 4 shows the state transition diagram of a NBCT, including five states and the necessary operations to trigger state transitions.

Figure 5 lists the procedures for the operator to . manage the NBCT database and NBCT subscriptions, including Query, Subscribe, Unsubscribe,

Activate, Deactivate, Upload and Remove functions. Figure 6 lists the procedures for a user to manage NBCT subscription, including Query, Subscribe, Unsubscribe, Activate, Deactivate, and Notify functions.

Figure 7 shows the procedure to establish a NBCT service in a multimedia call.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENTS

To illuminate the present invention clearly, some examples of content transformation are provided first as follows.

Referring to fig.l, picture 100 is original image before transformed. Picture 101 is a sample video image after content transformation, which can be used for privacy protection. Picture 103 adds some funny factors, such as cap and beard. In picture 102, a mask is added to mask the face within the original image, which can be used both for privacy protection and for leisure amusement. Referring to fig.2A, in a terminal-based content transformation (TBCT) system of prior art, a user terminal 201 has a multimedia capture function and a content transformation function (other functions not shown). The terminal

201 captures media source and implements content transformation, before transporting to remote user terminal via network. Referring to fig.2B₅ in a network-based content transformation (NBCT) of the present invention, a user terminal 202 only needs a multimedia capture function to capture media source. The media stream is transformed in. content by a content transformation function of NBCT system 203 (other functions not shown), and then sent to remote user terminal via network.

It should be noted that in prior art, the mathematical algorithms to implement transformations of media contents are already developed, and are utilized in some user terminals in terminal-based content transformation (TBCT) systems. Nevertheless, the present invention takes a unique approach by utilizing and controlling the shared servers in network side to offer the desired content transformation functions to massive number of regular user terminals. In the present invention, an NBCT (or an NBCT service) refers to a network-based content transformation service, whereas an NBCT program refers to an implementation of a content transformation algorithm. One or more NBCT services can be applied to a media stream in a multimedia call.

Operators can create or customize different NBCT service according to different media types and requirement. NBCT may be configured as a mandatory service for all users, or may be offered as a value-added service. NBCT may be triggered by the user or by the operator for a user. NBCT may be selectively applied to the contents of one or more or all media flows in a multimedia communication session. The two directions in any multimedia communication session are independent in their NBCT operations, i.e. whether one direction has NBCT has no impact to the other direction, and whatever NBCT is used in one direction has no impact the other direction. A user may apply different NBCTs to different receivers to allow personalization. Combined with figures, the embodiments of the invention will be illustrated in details as follows. . _{. .}

The illustration of the present invention consists two parts: the

io ^{, • •} architecture and functions of Network-Based Content Transformation (NBCT) systems, and the methods for managing and controlling NBCTs in a multimedia communication session.

Part A: Design of Network-Based Content Transformation (NBCT)

System

Scope of NBCT System:

The scope of a NBCT system includes all and only the functions that are specifically added into the existing network infrastructure to support the NBCT applications.

Put in another way, beyond the scope of the NBCT system are the functions that exist in the network regardless of the NBCT applications, although they may interact with the NBCT system. For example, such functions may include, but not limited to, the user terminals, the call server functions (e.g. PSTN switches, softswitches, mobile switches, or IP Multimedia Subsystem Call Session Control Function), the subscriber database system functions (e.g. Home Subscription Server (HSS))_* the billing system, and the network management system.

NBCT System Architecture: According to an embodiment of the invention, a NBCT system consists of the following logical functions, as shown in Figure 3: . . _...

Module 301a ~ 301n: NUCF (NBCT User Client Function); Module 302: NUPF (NBCT User Portal Function); Module 303: NCF(NBCT Charging Function); . . Module 304: NDF(NBCT Database Function);

Module 305: NASF(NBCT Application Server Function); Module 306: NMSF(NBCT Media Server Functions); Module 307 : NOPF(NBCT Operator Portal Function; Module 308a ~ 308n: NOCF(NBCT Operator Client Function).

Note these functions are logical functions and may optionally be combined into one or more physical devices in actual implementations. For example, NUCF 301 can reside inside or outside of a user terminal.

The logical functions are illuminated in detail as follows:

NBCT Media Server Function (NMSF):

The NBCT Media Server Function supports the following functions:

- Load NBCT programs from NBCT Database Function (NDF)

- Accept control commands from NASF

- Allocate media processing resources and network resources - Return allocated addresses of allocated network resources to NASF

- Perform the content transformations demanded by NASF

NBCT Application Server Function (NASF):

The NBCT Media Server Function supports the following functions: - Interact with Call Server to set up a multimedia call

- Look up the NBCT Database Function to find out the active NBCTs applicable to the caller

- Control the NBCT Media Server Function to allocate required media resources and network resources - Generate session detail records on usage of NBCTs and store to NBCT

Database Function NBCT Database Function (NDF):

The NBCT Database Function supports the following functions:

- Store NBCT programs uploaded

- Manage uploads, downloads, and updates of NBCT programs - Manage user subscriptions to NBCTs

- Manage user activations/deactivations to subscribed NBCTs

- Store NBCT usage data

NBCT Operator Portal Function (NOPF): The NBCT Operator Portal Function (NOPF) supports the following functions:

- Managing NBCT Programs: o Upload one or more NBCT programs into the NBCT database o Add one or more NBCT programs into the NBCT database o Remove one or more NBCT programs from the NBCT database o Modify one or more NBCT programs in the NBCT database o Test one or more NBCT programs in the NBCT database

- Managing NBCT subscriptions to users: o Subscribe a user to one or more NBCT programs o Unsubscribe a user out of one or more NBCT programs o Subscribe one or more users to a NBCT program o Unsubscribe one or more users out of a NBCT program o Query the NBCT programs subscribed by one or more users o Query the users subscribed to one or more NBCT programs - Managing active NBCTs to users: o Activate one or more NBCT programs subscribed by a user

. o Deactivate one or more NBCT programs subscribed by a user o Activate one or more users to a NBCT program o Deactivate one or more users out of a NBCT program o Query the NBCT programs activated by one or more users o Query the users activated to one or more NBCT programs

NBCT User Portal Function:

The NBCT User Portal Function (NUPF) supports the following functions:

- Managing NBCT subscriptions: o Subscribe the user to one or more NBCT programs o Unsubscribe the user out of one or more NBCT programs o Query the NBCT programs subscribed by the user

- Managing active NBCTs: o Activate one or more NBCT programs subscribed by the user o Deactivate one or more NBCT programs subscribed by the user o Query the NBCT programs activated by the user

- Notification of available NBCTs: o Notify users of new NBCT programs available for subscription

NBCT Charging Function (NCF):

The NBCT Charging Function supports the following functions:

- Retrieve NBCT usage data from NBCT Database Function

- Generate charging records according to operator-defined billing policies

NBCT Operator Client Function (NOCF):

The NBCT Operator Client Function (NOCF) supports the following functions: - Provide interfaces for managing NBCT Programs: o Upload one or more NBCT programs into the NBCT database o Remove one or more NBCT programs from the NBCT database o Modify one or more NBCT programs in the NBCT database o Test one or more NBCT programs in the NBCT database

- Provides interfaces for managing NBCT subscriptions to users: o Subscribe a user to one or more NBCT programs o Unsubscribe a user out of one or more NBCT programs o Subscribe one or more users to a NBCT program o Unsubscribe one or more users out of a NBCT program o Query the NBCT programs subscribed by one or more users o Query the users subscribed to one or more NBCT programs

- Provides interfaces for managing active NBCTs to users: o Activate one or more NBCT programs subscribed by a user o Deactivate one or more NBCT programs subscribed by a user o Activate one or more users to a NBCT program o Deactivate one or more users out of a NBCT program o Query the NBCT programs activated by one or more users o Query the users activated to one or more NBCT programs

NBCT User Client Function: . .

The NBCT User Client Function (NUCF) supports the following functions:

- Provide user interfaces for managing NBCT subscriptions: o Subscribe the user to one or more NBCT programs o Unsubscribe the user out of one or more NBCT programs o Query the NBCT programs subscribed by the user

- Providing user interfaces for managing active NBCTs: o Activate one or more NBCT programs subscribed by the user o Deactivate one or more NBCT programs subscribed by the user o Query the NBCT programs activated by the user

- Providing user interface for notification of available NBCTs: o Notify users of new NBCT programs available for subscription

Note:

- The NBCT client function may reside in the user terminal itself or outside of the user terminal, for example, inside a Web browser. - NBCT will require no hardware or software changes to the user terminal if the NBCT user client function resides outside of the user terminal. This will maximize the applicability of NBCT services by supporting existing user terminals.

- Additional convenience, interactivity and flexibility are provided if the NBCT user client function resides inside the user terminal. This implies the user terminal may require some software upgrades that implements the NBCT User Client Function.

Part B: Methods for Managing and Controlling NBCT in Multimedia Communications

This invention also discloses the methods of managing and controlling Network-Based Content Transformation services in a multimedia communication sessions, which include several aspects as follows:

- The state transition diagram of a NBCT as shown in Figure 4; - The procedures for the operator to manage NBCT database functions and user subscriptions;

- The procedures for a user to manage user subscriptions; - The procedure to establish a NBCT service in a multimedia call.

The Overall Procedure for Deploying a NBCT: The general steps for deploying a NBCT are shown in Figure 4, which includes five states of a NBCT and multiple events and operations to trigger the state transitions.

-The set of NBCT states include:

- "Created" state: when a NBCT program is created but not uploaded into the NBCT Database Function. - "Available for subscription" state: after a NBCT program is uploaded into the NBCT Database Function.

- "Subscribed" state: when a NBCT is subscribed by a user or assigned to a user by the operator. . .

- "Active" state: when a NBCT is activated by a user or activated to a user by the operator.

- "Operating" state: when a NBCT is being invoked in an active call to perform the content transformations to the selected media flows.

The deployment of a NBCT service follows these steps: 1. Initially, a program to implement a NBCT is created.

2. The NBCT program is uploaded into the NBCT Database Function.

3. A user subscribes to the NBCT.

4. A user activates one or more NBCTs put of her subscribed NBCTs. . Note: a user may subscribe to multiple NBCTs but only activate a subset of them at a given time.

5. When the user originates or terminates (receives) a multimedia call, the NBCT is triggered into operating state and applied to the selected media flow.

Procedures for Operator to Manage NBCT

The procedures for the operator to manage NBCT subscription and NBCT database are shown in Figure 5, which include the following procedures:

Procedure 501: Query command and response, which queries which NBCT services are subscribed/unsubscribed/activated/deactivated to an or more users, and which users subscribe/unsubscribe/activate/deactivate to one ore more NBCT, etc.

Procedure 502: Subscribe command and response, which subscribes one or more users to one or more NBCT services.

Procedure 503: Unsubscribe command and response, which unsubscribes one or more users out of one or more NBCT services. Procedure 504: Activate command and response, which activates one or more users to one or more NBCT services.

Note: The activate command may include the contact addresses of the remote user (e.g. phone numbers, Universal Resource Identifier) to support personalization and customization, namely, different NBCTs may be applied to different remote users to differentiate the levels of privacy protection and amusement.

Note: The activate command may include parameters to indicate when to apply the activated NBCT:

- Immediately; - For subsequent calls;

- Delayed; - Etc. Procedure 505: Deactivate command and response, which deactivates one or more users out of one or more NBCT services.

Note: The deactivate command may include parameters to indicate when to apply the deactivated NBCT: - Immediately;

- For subsequent calls;

- Delayed; - Etc.

Procedure 506: Upload command and response, which uploads one or more NBCTs to the NBCT database.

Procedure 507: Remove command and response, which removes one or more NBCTs out of the NBCT database.

Procedures for User to Manage NBCT The procedures for a user to manage NBCT subscription are shown in

Figure 6, which include the following procedures:

Procedure 601: Query command and response, which queries which NBCT services the user has subscribed and/or activated to.

Procedure 602: Subscribe command and response, which subscribes to one or more NBCT services.

Procedure 603: Unsubscribe command and response, which unsubscribes out of one or more NBCT services.

Procedure 604: Activate command and response, which activates one or more NBCT services. Note: The activate command may include the contact addresses of the remote user (e.g. phone numbers, Universal Resource Identifier) to support personalization and customization, namely, different NBCTs may be applied to different remote users to differentiate the levels of privacy protection and amusement. , .

Note: The activate command may include parameters to indicate when to apply the activated NBCT: - Immediately;

- For subsequent calls;

- Delayed;

- Etc.

Procedure 605: Deactivate command and response, which deactivates one or more NBCT services.

Note: The deactivate command may include parameters to indicate when to apply the deactivated NBCT:

- Immediately

- For subsequent calls - Delayed

- Etc.

Procedure for Controlling NBCT in a Multimedia Communication Session: The NBCT service may or may not be triggered in a multimedia communication session, depending on operator policy and user subscriptions. Whether to trigger NBCT is provisioned in the subscriber database outside the scope of this invention.

The general procedure for controlling NBCT in a multimedia communication session includes the following steps, as shown in Figure 7 (with corresponding step numbers):

Step 1: User Terminal A sends call set up message to Call Server, which includes its local network addresses to send and receive media flows, respectively.

Step 2: Call Server queries subscriber database the subscribed services including whether NBCT is enabled to this user. Step 3: Subscriber Database returns, among other things, whether the user has subscribed to any NBCT services.

Step 4: Call Server decides whether to trigger NBCT for this call: a) If the user has no subscription to NBCT service, go directly to step 11; b) If the call is for emergency service, go directly to step 11; .. c) If the user is subject to lawful interception (and the destination of the current call leg is a law enforcement point), go directly to step

d) If there are other operator policies to disallow NBCT, go directly to step 11; e) Otherwise, continue.

Step 5: Call Server forwards call setup message to the NBCT Application Server Function (NASF).

Step 6: The NASF queries the NBCT Database Function (NDF) for subscription information for the current source user and destination user.

Step 7: The NDF returns, among other things, the list of active NBCTs that should be applied and what media flows should be applied to.

Step 8: The NASF requests the NBCT Media Server Function (NMSF) to allocate resources for the selected active NBCTs. Step 9: The NMSF allocates and returns the local network address to receive media flows from User Terminal A, and the local network address to send media flows to destination user. Step 10: The NASF modifies the call setup message and send back to

Call Server. Note this call setup message includes both the network addresses of User Terminal A for receiving media flows from destination

User terminal B₅ as allocated in step I₅ and the network addresses of NMSF to send media flows to destination user B₅ as allocated in step 9.

Step 11 : The Call Server forwards call setup message to the Call Server managing the destination user Terminal B.

Note: If both users are managed by the same call server, this becomes a special case. Step 12: Destination Call Server checks whether the terminating user has NBCT services. .

Step 13: The Subscriber Database returns, among other things, whether the user has subscribed to any NBCT services.

In this example of Figure 7, we assume the terminating user has no NBCT services. This also shows that the two directions may be independent.

Step 14: Destination Call Server forwards call setup message to terminating user Terminal B.

Step 15: Terminating user Terminal B sends back acknowledgement, which includes the network addresses to receive media flows.

Step 16: Destination Call Server forwards acknowledgement back to Originating Call Server.

Step 17: Originating Call Server checks whether NBCT service is disallowed in step 4. If so, go directly to step 22; otherwise, continue,. Step 18: Call Server forwards acknowledgement to NBCT Application

Server Function (NASF).

Step 19: The NASF forwards acknowledgement to NBCT Media Server Function (NMSF).

Step 20: The NMSF returns to NASF an acknowledgement, which includes the network addresses of NMSF to receive media flows from User Terminal A, which is allocated in step 9. Step 21 : NASF returns acknowledgement to Call Server.

Step 22: Call Server sends back acknowledgement to User Terminal A.

Step 23: At this moment the call is established. User Terminal A starts to send media flows to the NBCT Media Server Function (NMSF).

Step 24: The NMSF performs selected NBCTs to the received media flows.

Step 25: The NMSF sends out transformed media flows to network address of B, which has obtained the sending network address of NMSF in step 14.

Step 26: User Terminal B sends out media streams directly to the network address of user A obtained in step 14. ^■ _; . .

Procedure for Emergency Call:

The procedure for emergency calls is a special case of the general control procedure, where in step 4 the Call Server find out the destination number is for an emergency service and decides NBCT should be disallowed in emergency calls and thus skips steps 5 to 10 and 17 to 20.

Procedures for Lawful Interception:

The procedure for lawful interception is a special case of the general control procedure, where in step 4 the Call Server find out the caller is subject to lawful interception and decides NBCT should be disallowed in this case and thus skips steps 5 to 10 and 17 to 20. :

Claims

1. A system for managing and controlling Network-Based Content Transformation (NBCT) functionality in multimedia communication services, comprising: a NBCT Database Function (NDF) for storing NBCT programs uploaded, managing uploads, downloads and updates of NBCT programs, managing user subscriptions to NBCTs, and managing user activations to subscribed NBCTs; a NBCT Application Server Function (NASF) for interacting with a Call Server to set up a multimedia call, looking up the NDF to find out an active NBCT applicable to the caller; a NBCT Media Server Functions (NMSF) for loading NBCT programs from the NDF, accepting control commands from the NASF, allocating media processing resources and network resources based on a control of the NASF, returning allocated addresses of allocated network resources to the NASF₅ and performing the content transformations demanded by the NASF; a NBCT Operator Portal Function (NOPF) for managing NBCT programs, managing NBCT subscriptions to users, and managing active NBCTs to users;. a NBCT User Portal Function (NUPF) for managing NBCT subscriptions, managing active NBCTs, and controlling a notification of available NBCTs; a NBCT Operator Client Function (NOCF) for providing. interfaces for managing NBCT Programs, providing interfaces for managing NBGT subscriptions to users, and providing interfaces for managing active NBCTs to users; and a NBCT User Client Function (NUCF) for providing user interfaces for managing NBCT subscriptions, providing user interfaces for managing active NBCTs, and providing user interface for notification of available NBGTs.

2. The system as claim I₅ wherein the NASF is further for generating session detail records on usage of NBCT services and storing to the NDF; and the database function module is further for storing the NBCT usage data.

3. The system as claim 2, further comprising a NBCT Charging Function (NCF) for retrieving NBCT usage data from the NDF, and generating charging records according to operator-defined billing policies.

4. A method for deploying Network-Based Content Transformation (NBCT), comprising: creating a NBCT program to implement a content transformation; uploading the NBCT program into a NBCT Database Function (NDF); subscribing a user to a NBCT service; activating the NBCT for the user; and triggering the NBCT and applying to a selected media flow, when the user originates or terminates a multimedia call.

5. The method as claim 4, further comprising: removing a NBCT out of the NDF. . _{. .} . .

6. The method as claim 4, further comprising: unsubscribing a user out of a NBCT service.

7. The method as claim 4, further comprising: deactivating a user out of a NBCT service.

8. The method as claim 4, further comprising: querying a NBCT for a user.

9. The method as claim 4, wherein the NBCT is triggered by a user or by an operator for a user.

10. The method as claim 4, wherein the NBCT is selectively applied to the contents of one or more or all media flows in a multimedia communication session.

11. The method as claim 4, wherein the NBCT is independently operated at two directions in any multimedia communication session.

12. A method for controlling a Network-Based Content Transformation (NBCT) in a multimedia communication session, comprising the following steps:

(1) User A sends a call set up message to a Call Server, which includes a network addresses to send and receive media flows, respectively;

(2) The Call Server queries subscriber database the subscribed services including whether NBCT is enabled to this user; (3) Subscribe returns, among other things, whether the user has subscribed to any NBCT services;

(4) Call Server decides whether to trigger NBCT for this call;

(5) Call Server forwards the call setup message to the NBCT Application Server Function (NASF); (6) The NASF queries the NBCT Database Function (NDF). for subscription information for the current source user and destination user;

(7) The NDF returns, among other things, the list of active NBCTs that should be applied and what media flows should be applied to;

(8) The NASF requests the NBCT Media Server Function (NMSF) to allocate resources for the selected active NBCTs;

(9) The NMSF allocates and returns the network address to receive media flows from User A, and the. network address to send media flows to destination user;

(10) The NASF modifies the call setup message and send back to Call Server, where the call setup message includes both User A's network addresses for receiving media flows and the network addresses of NMSF to send media flows to destination user B; (11) The Call Server forwards the call setup message to the Call Server managing the destination user B;

(12) Destination Call Server checks whether the terminating user has NBCT services; (13) The Subscriber Database returns, among other things, whether the user has subscribed to any NBCT services;

(14) Destination Call Server forwards call setup message to terminating user B;

(15) Terminating user B sends back acknowledgement, which includes the network addresses to receive media flows;

(16) Destination Call Server forwards acknowledgement back to Originating Call Server;

(17) Originating Call Server checks whether NBCT service is disallowed, if so, go directly to step (22); otherwise, continue; (18) Call Server forwards acknowledgement to NBCT Application Server

Function (NASF);

(19) The NASF forwards acknowledgement to NBCT Media Server Function (NMSF);

(20) The NMSF returns to NASF an acknowledgement, which includes the network addresses of NMSF to receive media flows from User A;

(21) NASF returns acknowledgement to Call Server;

(22) Call Server sends back acknowledgement to User A;

(23) User A starts to send media flows to the NBCT Media Server Function (NMSF); and . . . (24) The NMSF performs selected NBCTs to the received media flows.

13. The method as claim 11 , further comprising the steps : (25) The NMSF sends out transformed media flows to network address of B; and

(26) User B sends out media streams directly to the network address of user A.

14. The method as claim 11₅ wherein the step (4) comprises: a. If the user has no subscription to NBCT service, go directly to step

(H); b. If the call is for emergency service, go directly to step (11); c. If the user is subject to lawful interception, go directly to step (11); d. If there are other operator policies to disallow NBCT, go directly to step (11); and e. Otherwise, continue.

15. A system for implementing Network-Based Content Transformation (NBCT) in multimedia communication services, comprising: a database function module for storing NBCT programs, and recording their status associated with different users; an operator portal function module for managing the NBCT programs and their status associated with different users; an or more operator client function modules for providing interfaces to communicate with the operator portal function module; a user portal function module for managing NBCT subscriptions and activations to users; . .. . ., a or more user client function modules for providing user interfaces to communicate with the user portal function module; an application server function module for interacting with Call Server to set up a multimedia call based on a call set up message sent by. a user terminal, and looking up the database function module to select the active NBCT programs applicable to the user; and a media server function module for loading the selected NBCT programs, under the controlling of the application server function module, allocating media processing resources and network resources, and returning network addresses of allocated media processing resources to receive one or more media flows from an original user terminal and send to a destination user terminal after performing the selected content transformations with the loaded NBCT programs.

16. The system as claim 15, wherein the application server function module is further for generating session detail records on usage of NBCT services and storing to the database function module; and the database function module is further for storing the NBCT usage data.

17. The system as claim 16, further comprising a charging function module for retrieving NBCT usage data from the database function module, and generating charging records according to operator-defined billing policies.

18. A method for implementing Network-Based Content Transformation (NBCT) in multimedia communication services, comprising: creating one or more NBCT programs and storing to a database; subscribing/unsubscribing one or more users to one or more. NBCT programs; activating/deactivating one or more users to one or more NBCT programs; . . interacting with Call Server to set up a multimedia call based on a call set up message sent by a user, and looking up the database to select an active NBCT program applicable to the user; and loading the selected NBCT programs, allocating media processing resources and network resources, and returning addresses of allocated network resources to receive a media flow from an original user terminal and send to a destination user terminal after performing a content transformation based on the loaded NBCT program.

19. The method as claim 18, further comprising: generating session detail records on usage of NBCT services and storing to the database.

20. The method as claim 19, further comprising: retrieving NBCT usage data from the database, and generating charging records according to operator-defined billing policies.

21. The method as claim 18, wherein the NBCT programs are subscribed or activated according to a request from a user, or an assignment from an operator.