WO2007080358A1

WO2007080358A1 - Service replacement management in dvb systems

Info

Publication number: WO2007080358A1
Application number: PCT/GB2006/000100
Authority: WO
Inventors: Jie Wang
Original assignee: Nds Limited
Priority date: 2006-01-11
Filing date: 2006-01-11
Publication date: 2007-07-19

Abstract

A method for managing service replacement in a digital video broadcasting (DVB) system, the method including detecting a replacement of a first service (A) with a replacement service (B) in a DVB transmission received at a set-top box (STB) (102), and providing a message indicating the occurrence of the replacement.

Description

SERVICE REPLACEMENT MANAGEMENT IN DVB SYSTEMS

FIELD OF THE INVENTION

The present invention relates to television systems in general, and more particularly to service replacement management in Digital Video Broadcasting (DVB) systems.

BACKGROUND OF THE INVENTION

In some Digital Video Broadcasting (DVB) systems, a service, which is defined as a sequence of programs under the control of a broadcaster which can be broadcast as part of a schedule, may be replaced during a time window by another ₍ service in various ways. In one scenario, two or more services, such as one relating to sports and one relating to news, share the same broadcast channel, where at any given time programs from only one service are broadcast over the channel, with each service occupying the channel for a limited time. When switching between services, some of the service characteristics, such as the service name and the service type, might not be the same. In another scenario, service replacement may occur to support a multiple-level broadcast network, such as one with a national, regional, and local content hierarchy. In this scenario, higher-level services are broadcast during some periods, replaced by lower-level services during other periods. Here, too, the various services might have different service characteristics, such as being under different service names.

Currently, DVB service replacements are carried out without the knowledge of the viewer. Usually, such replacements are carried out just prior to or during the replaced broadcast, such that there is usually no time to update Electronic Program Guide information in a way that would provide timely notification of the change to the viewer.

It would therefore be advantageous for DVB STBs to be able to detect the switch to replacement services to support timely notifications to viewers of changes in service.

PCT International Application No. PCT/GB97/01025 is believed to be representative of the art.

SUMMARY OF THE INVENTION The present invention provides systems and methods relating to service replacement management in a DVB system.

In one aspect of the present invention a method is provided for managing service replacement in a digital video broadcasting (DVB) system, the method including detecting a replacement of a first service with a replacement service in a DVB transmission received at a set-top box (STB), and providing a message indicating the occurrence of the replacement.

In another aspect of the present invention a method is provided for managing service replacement in a digital video broadcasting (DVB) system, the method including configuring a DVB Service Information (DVB-SI) compliant Service Description Table (SDT) to provide information regarding a first service and a replacement service for the first service, updating a Program Association Table (PAT) associated with a Transport Stream (TS) on which the services are carried by replacing the program_number of the first service with the service_ID of the replacement service to indicate that the first service has been replaced with the replacement service, detecting when the prograrnjiumber is updated to contain the service_ID of the replacement service, using the service_ID of the replacement service to retrieve information from the SDT relating to the replacement service, and providing a message indicating the occurrence of the replacement.

In another aspect of the present invention the method further includes determining the program_number of the replacement service by comparing a list of program_numbers in the PAT with a replacement service list in the SDT and identifying a common entry to both lists.

In another aspect of the present invention the method further includes transmitting the SDT and the PAT to a set-top box (STB), where any of the detecting, using, and providing steps are performed by the STB.

In another aspect of the present invention the configuring step includes configuring the SDT to indicate whether the first service and the replacement service use the same Event Information Table (EIT).

In another aspect of the present invention the configuring step includes designating the replacement service using a private linkage type.

In another aspect of the present invention the updating step includes updating a Program Map Table (PMT) indicated by the PAT by replacing the packet identifiers (PIDs) of the first service with the PIDs of the replacement service if the PIDs of the replacement service differ from the PIDs of the first service.

In another aspect of the present invention the providing step includes providing any of the information relating to the replacement service.

In another aspect of the present invention a method is provided for managing service replacement in a digital video broadcasting (DVB) system, the method including receiving a selection request for a replaceable service, determining if the requested service is currently running, playing a replacement service associated with the replaceable service if the replaceable service is not currently running, and providing a viewer indication regarding the replacement service.

In another aspect of the present invention the method further includes determining by comparing a program_number of a current PAT with a service_ID of a received SDT, where the replaceable service is not currently running if the program_number does not match the service_ID.

In another aspect of the present invention the method further includes providing a viewer indication that the replaceable service is not currently running, and prompting to receive an indication whether or not to select the replacement service.

In another aspect of the present invention a service replacement management system is provided for use with a digital video broadcasting (DVB) system, the system including a set-top box (STB) configured to detect a replacement of a first service with a replacement service in a DVB transmission, and messaging apparatus configured to provide a message indicating the occurrence of the replacement.

In another aspect of the present invention a service replacement management system is provided for use with a digital video broadcasting (DVB) system, the system including a DVB Service Information (DVB-SI) compliant Service Description Table (SDT) configured to provide information regarding a first service and a replacement service for the first service, a Program Association Table (PAT) associated with a Transport Stream (TS) on which the services are carried, where the program_number of the first service is replaced with the service_ID of the replacement service to indicate that the first service has been replaced with the replacement service, and a set-top box (STB) configured to detect when the program_number is updated to contain the serviceJD of the replacement service, use the service_ID of the replacement service to retrieve information from the SDT relating to the replacement service, and provide a message indicating the occurrence of the replacement.

In another aspect of the present invention the STB is further configured to determine the program_number of the replacement service by comparing a list of programjmmbers in the PAT with a replacement service list in the SDT and identifying a common entry to both lists.

In another aspect of the present invention the system further includes a head end configured to transmit the SDT and the PAT to the STB.

In another aspect of the present invention the SDT indicates whether the first service and the replacement service use the same Event Information Table (EIT).

In another aspect of the present invention the replacement service is designated using a private linkage type.

In another aspect of the present invention the system further includes a Program Map Table (PMT) indicated by the PAT in which the packet identifiers (PIDs) of the first service are replaced with the PIDs of the replacement service if the PIDs of the replacement service differ from the PIDs of the first service.

In another aspect of the present invention the STB is operative to provide any of the information relating to the replacement service.

In another aspect of the present invention a service replacement management system is provided for use with a digital video broadcasting (DVB) system, the system including a set-top box (STB) configured to receive a selection request for a replaceable service, determine if the requested service is currently running, and play a replacement service associated with the replaceable service if the replaceable service is not currently running, and messaging apparatus operative to provide a viewer indication regarding the replacement service.

In another aspect of the present invention the STB is further configured to determine by comparing a program_number of a current PAT with a service_ID of a received SDT, where the replaceable service is not currently running if the program_number does not match the service_ID.

In another aspect of the present invention the viewer indication indicates that the replaceable service is not currently running, and where the STB is further configured to prompt to receive an indication whether or not to select the replacement service. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:

Fig. IA is a simplified conceptual illustration of a system for service replacement management, constructed and operative in accordance with a preferred embodiment of the present invention;

Fig. IB is a simplified flowchart illustration of an exemplary method of operation of the system of Fig. IA, operative in accordance with a preferred embodiment of the present invention;

Figs. 1C and ID are simplified conceptual illustrations respectively of a Transport Stream without service replacement and a Transport Stream with service replacement during a time window;

Fig. 2 is a simplified flowchart illustration of an alternative exemplary method of operation of the system of Fig. IA, operative in accordance with a preferred embodiment of the present invention;

Fig. 3A is a simplified conceptual illustration of an alternative system for service replacement management by a local head-end, constructed and operative in accordance with a preferred embodiment of the present invention; and

Fig. 3B is a simplified flowchart illustration of an exemplary method of operation of the system of Fig. 3A, operative in accordance with a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Reference is now made to Fig. IA, which is a simplified conceptual illustration of a system for service replacement management, constructed and operative in accordance with a preferred embodiment of the present invention, and additionally to Fig. IB, which is a simplified flowchart illustration of an exemplary method of operation of the system of Fig. IA, operative in accordance with a preferred embodiment of the present invention. In Figs. IA and IB, a DVB Service Information (DVB-SI) compliant Service Description Table (SDT) 100 is configured to provide information regarding a service A, including information regarding a list of one or more replacement services B for service A. SDT 100 is also preferably configured to indicate whether service A and replacement service B use the same Event Information Table (EIT) or any other DVB-SI information. If an EIT is shared between service A and replacement service B, SDT 100 also preferably indicates which service identifier (i.e., DVB triplet) is used to identify the EIT sub-tables.

Where the service replacement supports a multiple-level broadcast network, such as one with a national, regional, and local content, the services of the various levels (e.g., regional, local) may also be associated with corresponding identifications, such as of the regions/locations where they are accessible. This information, if present, may be inserted in SDT 100 or equivalent service plan information data set. For example, a national DVB service known as Channel NTVl may have several regional channels, including one channel named "NTVl - Rl" for region Rl and another channel named "NTVl - R2" for region R2, where "NTVl - Rl" is not accessible for decoders in R2, and vice-versa. In SDT 100, the "NTVl - Rl" would be associated with an identifier indicating Rl, while "NTVl - R2" would be associated with an identifier indicating R2. The national service is usually available to all participating STBs throughout a country, and thus no national-level identifier would be necessary, although where the national service has limited coverage, an identifier may be associated with it. Using this signaling, an STB in region R2 would be programmed not to access "NTVl - Rl" when a channel replacement occurs on "NTVl".

A DVB-SI-compliant linkage descriptor with a linkage type=0x05 indicating "service replacement service" as specified by the DVB-SI standard, or a private linkage type may be used to designate replacement service B as such in accordance with conventional techniques. The linkage descriptor may also be extended to indicate the type of replacement service (e.g., local service, parent service, same service but in high definition (HD), same service but in standard definition (SD), partner service, etc.), as well as whether the replacing service shares the same EIT sub-tables as the replaced one. When the replacement service is of a multiple-level broadcast type, the linkage_descriptor may also be extended to indicate the level of that service. This allows, for example, STBs in one region to ignore a regional replacement service that belongs to a different region. The multiple replacement services need not be ordered within SDT 100. SDT 100 is then transmitted to an STB 102, such as by a broadcaster from a head end 104 in accordance with conventional techniques. STB 102 preferably stores service information previously extracted from SDT 100 aside from any information it does not require, such as information relating to a different region than that of STB 102. When, using any known service switching technique, the broadcaster of service A replaces service A with replacement service B, the main components of replacement service B may be carried by the same Transport Stream and using the same PID previously used by service A. Head-end 104 then updates a Program Association Table (PAT) 106 associated with a Transport Stream (TS) 108 on which services A and B are carried by replacing the program_number of service A with the service_ID of service B. Head-end 104 also preferably generates a new Program Map Table (PMT) within PAT 106 having a programjtiumber set to the value of the service_id of service B. The new PMT also preferably indicates the components included in service B. PAT 106 and its PMT are then transmitted to STB 102 from head end 104 in accordance with conventional techniques.

Prior to service A being replaced with service B, STB 102 receives TS 108 from head end 104 and provides service A content for viewing. As SDT 100 indicates that service A is a replaceable service, STB 102 monitors PAT 106 of the TS carrying service A to detect a service switch as indicated by the disappearance from the PAT of the program_number associated with the service A. When such a service switch is detected, STB 102 compares program_numbers found in PAT 106 to service_IDs previously extracted from SDT 100 that are identified as replacement services for service A to determine which replacement service is the one replacing service A. The programjαumber in PAT 106 that matches a replacement serviceJUD from SDT 100 indicates the service that replaces service A. Thus, the matching service_ID/program_number indicating that service B has replaced service A may then be used to retrieve information previously received in SDT 100 relating to service B, whereupon STB 102 may display any of the information relating to service B, thereby apprising current viewers of service A that it has been replaced by service B. STB 102 may also display the replacement type, such as "regional service," "national service," "daughter service," "parent service," "partner service," "same service but in HD," "same service but in SD," etc. STB 102 need not monitor PAT 106 when providing content of a non-replaceable service for viewing.

Reference is now made to Fig. 2, which is a simplified flowchart illustration of an exemplary alternative method of operation of the system of Fig. IA, operative in accordance with a preferred embodiment of the present invention. The method of Fig. 2 is substantially similar to the method of Fig. IB, with the notable exception that service A is replaced with service B at a time when STB 102 is not providing service A content for viewing. In the method of Fig. 2, when a viewer selects service A for viewing, STB 102 checks PAT 106 of TS 108 which carried service A. As PAT 106 now contains the program_number/service_ID of service B instead of that of service A, STB 102 compares program_numbers found in PAT 106 to service_IDs previously extracted from SDT 100 that are identified as replacement services for service A to determine which replacement service is the one replacing service A - namely, service B. STB 102 then uses the service_ID of service B to retrieve information previously received in SDT 100 that relates to service B. STB 102 may include messaging apparatus for displaying a message, such as on a connected television screen, informing the viewer of the non-availability of service A, and may also provide information about replacement service B and, optionally, information about the program being currently broadcast on service B by using the appropriate EIT. STB 102 may then ask the viewer whether or not to switch to the channel with replacement service B. Alternatively, STB 102 may display a message informing the viewer of the non-availability of service A, and may then ask the viewer whether or not to switch to the channel with replacement service B. If the viewer answers in the affirmative, STB 102 switches to the channel and may provide information about replacement service B and the program being currently broadcast on service B.

Where service A and replacement service B share the same EIT sub- tables, STB 102 may use service identifiers previously received in SDT 100 to acquire the program description from the EIT for replacement service B and display related program information on a connected display device.

The systems and methods described herein may be better understood with reference to Figs. 1C and ID, which are simplified conceptual illustrations respectively of a Transport Stream 180 without service replacement and a Transport Stream 190 with service replacement during a time window.

Figs. IA, IB, and 2 describe systems and methods for service replacement where a single head-end inserts both a replaceable service A and a replacement service B into a transport stream, each in a different time window. The head-end is also responsible for generating the necessary PSI/SI tables such as the SDT, PAT, EIT and PMT. When switching from a service A to a replacement service B, the head-end generates an updated PAT by replacing the program_number of service A with that of service B. Reference is now made to Fig. 3A, which is a simplified conceptual illustration of an alternative, system for service replacement management by multiple head-ends, constructed and operative in accordance with a preferred embodiment of the present invention, and Fig. 3B, which is a simplified flowchart illustration of an exemplary method of operation of the system of Fig. 3 A, operative in accordance with a preferred embodiment of the present invention. The system and method of Figs. 3A and 3B are substantially similar to the system of Fig. IA and the methods of Figs. IB and 2, with the notable exception that multiple head-ends are employed. A main head-end 300 generates a main TS 302 for transporting service A with corresponding PSI/SI tables, such as SDT 100, PAT 106, EITs and PMTs. A regional/local head-end 304 receives TS 302 and performs service replacement of service A during a specific time window. When regional/local head-end 304 replaces service A with service B, regional/local head-end 304 modifies the received PAT 106 by replacing the program_number of service A with that of service B to create a replacement PAT 306 that replaces original PAT 106. Regional/local head-end 304 need not modify other PSI/SI tables such as SDT 100, but is preferably responsible for generating a PMT for replacement service B. If service B shares the same EIT as service A, regional/local head-end 304 need not modify any EIT sub-tables received from main head-end 300. Where replacement service B does not share the same EIT sub-tables as service A, EIT sub-tables may be generated for replacement service B where main head-end 300 inserts EIT sub-tables into main TS 302 for both service A and service B, and regional/local head-end 304 need not be concerned with EIT sub-tables for service B. Alternatively, regional/local head-end 304 may generate EIT sub-tables for service B and insert them into a local TS 308. Prior to service replacement, regional/local headend 304 retransmits main TS 302 on local TS 308 to STB 102 along with PAT 106. During regional/local service replacement, regional/local head-end 304 transmits service B in place of service A on local TS 308 to STB 102 along with PAT 306. When the regional/local service is stopped, regional/local head-end 304 may once again retransmit the received main TS 302 to its local STB 102 without modification. It is appreciated that one main head-end may have multiple regional/local service insertion points at multiple regional/local head-ends, such as a different one for each region.

It is appreciated that various features of the invention which are, for clarity, described in the contexts of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable subcombination.

It is appreciated that one or more of the steps of any of the methods described herein may be omitted or carried out in a different order than that shown, without departing from the true spirit and scope of the invention.

While the methods and apparatus disclosed herein may or may not have been described with reference to specific computer hardware or software, it is appreciated that the methods and apparatus described herein may be readily implemented in computer hardware or software using conventional techniques.

Thus the present invention encompasses a carrier medium carrying machine readable instructions or computer code for controlling a programmable controller, computer or number of computers as the apparatus of the invention. The carrier medium can comprise any storage medium such as a floppy disk, CD ROM, DVD ROM, hard disk, magnetic tape, or programmable memory device, or a transient medium such as an electrical, optical, microwave, RF, electromagnetic, magnetic or acoustical signal. An example of such a signal is an encoded signal carrying a computer code over a communications network, e.g. a TCP/IP signal carrying computer code over an IP network such as the Internet, an intranet, or a local area network.

While the present invention has been described with reference to one or more specific embodiments, the description is intended to be illustrative of the invention as a whole and is not to be construed as limiting the invention to the embodiments shown. It is appreciated that various modifications may occur to those skilled in the art that, while not specifically shown herein, are nevertheless within the true spirit and scope of the invention. For example, the SDT may be used to indicate the current status of a service by setting the standard running_status in the SDT to indicate the status of the service as "not running," "start in a few seconds," "pausing," or "running." This indicator change may be monitored by STB 102 to detect a service start and termination. Furthermore, different DVB-SI standard tables may be used to manage the service running/not running status. For example, the running status in the SDT may be used to detect the service end. A standard linkage descriptor in the SDT may be used to declare the replacement services.

Claims

CLAIMS What is claimed is:

1. A method for managing service replacement in a digital video broadcasting (DVB) system, the method comprising: detecting a replacement of a first service with a replacement service in a DVB transmission received at a set-top box (STB); and providing a message indicating said occurrence of said replacement.

2. A method for managing service replacement in a digital video broadcasting (DVB) system, the method comprising: configuring a DVB Service Information (DVB-SI) compliant Service Description Table (SDT) to provide information regarding a first service and a replacement service for said first service; updating a Program Association Table (PAT) associated with a Transport Stream (TS) on which said services are carried by replacing the program_number of said first service with the service_ID of said replacement service to indicate that said first service has been replaced with said replacement service; detecting when said program_number is updated to contain said service_ TD of said replacement service; using said service_ID of said replacement service to retrieve information from said SDT relating to said replacement service; and providing a message indicating said occurrence of said replacement.

3. A method according to claim 2 and further comprising determining said program_number of said replacement service by comparing a list of programjnumbers in said PAT with a replacement service list in said SDT and identifying a common entry to both lists.

4. A method according to either of claim 2 and claim 3 and further comprising transmitting said SDT and said PAT to a set-top box (STB), wherein any of said detecting, using, and providing steps are performed by said STB.

5. A method according to any of claims 2 - 4 wherein said configuring step comprises configuring said SDT to indicate whether said first service and said replacement service use the same Event Information Table (EIT).

6. A method according to any of claims 2 - 5 wherein said configuring step comprises designating said replacement service using a private linkage type.

7. A method according to any of claims 2 — 6 wherein said updating step comprises updating a Program Map Table (PMT) indicated by said PAT by replacing the packet identifiers (PIDs) of said first service with the PIDs of said replacement service if the PIDs of said replacement service differ from the PIDs of said first service.

8. A method according to any of claims 2 — 7 wherein said providing step comprises providing any of said information relating to said replacement service.

9. A method for managing service replacement in a digital video broadcasting (DVB) system, the method comprising: receiving a selection request for a replaceable service; determining if said requested service is currently running; playing a replacement service associated with said replaceable service if said replaceable service is not currently running; and providing a viewer indication regarding said replacement service.

10. A method according to claim 9 and further comprising determining by comparing a program_number of a current PAT with a serviceJGD of a received SDT, wherein said replaceable service is not currently running if said program_number does not match said service_ID.

11. A method according to either of claim 9 and claim 10 and further comprising: providing a viewer indication that said replaceable service is not currently running; and prompting to receive an indication whether or not to select said replacement service.

12. A service replacement management system for use with a digital video broadcasting (DVB) system, the system comprising: a set-top box (STB) configured to detect a replacement of a first service with a replacement service in a DVB transmission; and messaging apparatus configured to provide a message indicating said occurrence of said replacement.

13. A service replacement management system for use with a digital video broadcasting (DVB) system, the system comprising: a DVB Service Information (DVB-SI) compliant Service Description Table (SDT) configured to provide information regarding a first service and a replacement service for said first service; a Program Association Table (PAT) associated with a Transport Stream (TS) on which said services are carried, wherein the program_number of said first service is replaced with the service_ID of said replacement service to indicate that said first service has been replaced with said replacement service; and a set-top box (STB) configured to: detect when said programjnumber is updated to contain said service_ID of said replacement service, use said service_ID of said replacement service to retrieve information from said SDT relating to said replacement service, and provide a message indicating said occurrence of said replacement.

14. A system according to claim 13 wherein said STB is further configured to determine said programjnumber of said replacement service by comparing a list of program_numbers in said PAT with a replacement service list in said SDT and identifying a common entry to both lists.

15. A system according to either of claim 13 and claim 14 and further comprising a head end configured to transmit said SDT and said PAT to said STB.

16. A system according to any of claims 13 - 15 wherein said SDT indicates whether said first service and said replacement service use the same Event Information Table (EIT).

17. A system according to any of claims 13 - 16 wherein said replacement service is designated using a private linkage type.

18. A system according to any of claims 13 - 17 and further comprising a Program Map Table (PMT) indicated by said PAT in which the packet identifiers (PIDs) of said first service are replaced with the PIDs of said replacement service if the PIDs of said replacement service differ from the PIDs of said first service.

19. A system according to any of claims 13 - 18 wherein said STB is operative to provide any of said information relating to said replacement service.

20. A service replacement management system for use with a digital video broadcasting (DVB) system, the system comprising: a set-top box (STB) configured to: receive a selection request for a replaceable service, determine if said requested service is currently running, and play a replacement service associated with said replaceable service if said replaceable service is not currently running; and messaging apparatus operative to provide a viewer indication regarding said replacement service.

21. A system according to claim 20 wherein said STB is further configured to determine by comparing a prograrn_number of a current PAT with a service_ID of a received SDT, wherein said replaceable service is not currently running if said program_number does not match said service_ID.

22. A system according to either of claim 20 and claim 21 wherein said viewer indication indicates that said replaceable service is not currently running, and wherein said STB is further configured to prompt to receive an indication whether or not to select said replacement service.

23. A carrier medium carrying computer readable code for controlling a computer to carry out the method of any one of claims 1 to 11.

ifi