JP3676165B2 - Digital television broadcasting system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital television broadcasting system that provides services from a plurality of networks.
[0002]
[Prior art and problems to be solved by the invention]
Assume a case where a plurality of broadcast transmission companies, that is, services from a plurality of networks are received by one television broadcast receiver. Each network transmits a service number for each transponder that constitutes its own network, but does not transmit a service number for each transponder that constitutes another network.
[0003]
For this reason, when the service is switched from the service (program) of the predetermined network currently received to the service of another network on the receiver side, the user first switches the network and switches the network. After obtaining the service number for each transponder that constitutes, the program switching operation must be performed. Such an operation is troublesome for the user.
[0004]
Therefore, for each network, the service number for each transponder that constitutes the other network is transmitted together with the service number for each transponder that constitutes its own network. A system is conceivable in which these pieces of information are acquired and stored from an existing network, and when switching of services across networks is requested, switching of services is performed based on that information.
[0005]
However, in such a system, for each network, it is necessary to transmit the service number for each transponder that constitutes another network together with the service number for each transponder that constitutes its own network. There is a problem that the amount of information to be transmitted increases.
[0006]
In addition, when each network transmits only the service number of each transponder that constitutes its own network, each network is received by sequentially receiving each network when the power is turned on. The service number for each transponder that is configured is acquired and stored in sequence, and when switching of services across networks is requested, switching of services is performed based on such information. A system is conceivable. However, in this method, if a service in a network that is not currently received is changed, added, or deleted, the changed contents, added contents, or deleted contents can be known unless the service is normally transferred to the network. Because it is not possible, the service switching may not be performed smoothly.
[0007]
[Problems to be solved by the invention]
It is an object of the present invention to provide a digital television broadcast system that enables a user to switch services across networks without performing a network switching operation.
[0008]
[Means for Solving the Problems]
The digital television broadcast system according to the present invention is a digital television broadcast system that provides services from a plurality of networks. For each network, the transmission specifications of the own network and the transponders constituting the own network are provided. The service number is sent as actual-NIT, the transmission specifications of the other network, and information on the services of other networks that are added, deleted or changed after the present, and the addition, deletion or change are valid. Service change information consisting of information related to the valid time is transmitted as other-NIT, and the receiver receives the actual-NIT and other-NIT transmitted for each network when the power is turned on. , Memorize the transmission specifications for all networks and Means for creating a service change information table storing service change information and a service table storing service numbers for all networks and networks corresponding to the service numbers, and when a user inputs a service number, Based on the service table, by recognizing the network corresponding to the input service number, means for selecting a program corresponding to the service number, when receiving a service provided by a certain network, A network that provides a means to update the service table based on the acquired actual-NIT, when the actual-NIT sent from the network is periodically acquired and the acquired actual-NIT is updated. Othe sent from the network when receiving the service If it is necessary to periodically obtain r-NIT and update the service change information table, the means for updating the service change information table and the current time is one of the service change information in the service change information table. And a means for updating the service table based on the service change information whose valid time coincides with the current time.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0010]
FIG. 1 shows the electrical configuration of a digital broadcast receiver.
[0011]
A tuner 1 receives a broadcast wave from an antenna, demodulates it, and outputs a transport stream (hereinafter abbreviated as TS). Reference numeral 2 denotes a TS separation unit that separates the TS output from the tuner 1 into video, audio, and other additional information. Additional information is stored in the memory 3.
[0012]
A video processing unit 5 decodes the video TS output from the TS separation unit 2 and outputs the video. An on-screen generation unit 4 generates an on-screen image such as a program guide screen. Reference numeral 10 denotes an image composition unit for displaying the screen output by superimposing the on-screen image generated by the on-screen generation unit 4 on the video output obtained by the video processing unit 5. The video signal obtained by the image composition unit 10 is sent to the video output terminal 7.
[0013]
Reference numeral 6 denotes an audio processing unit for decoding the audio TS output from the TS separation unit 2 and outputting the audio. The audio signal obtained by the audio processing unit 6 is sent to the audio output terminal 8. Reference numeral 9 denotes a CPU for controlling each part of the digital broadcast receiver.
[0014]
In this example, it is assumed that the digital broadcast receiver can receive a plurality of networks. Each network periodically transmits actual-NIT and other-NIT as NIT (Network Information Table).
[0015]
The actual-NIT includes the transmission specifications of the own network and the service number for each transponder that constitutes the own network. The transmission specifications of the own network include transmission information such as the frequency, the orbit position of the satellite, and the modulation method for each transponder constituting the own network.
[0016]
The other-NIT includes transmission specifications of other networks and service change information. Transmission specifications of other networks include transmission information such as frequency, satellite orbital position, and modulation method for each transponder constituting the other network. The service change information includes information regarding services of other networks that are added, deleted, or changed after the present time, and information regarding valid times when the addition, deletion, or change is valid.
[0017]
FIG. 2 shows an initial service table creation processing procedure performed by the digital broadcast receiver when the power is turned on.
[0018]
First, actual-NIT and other-NIT transmitted from a predetermined network are acquired and stored (step 1). That is, the CPU 9 controls the tuner 1 to switch the transponder desired to be received by the transponder corresponding to the predetermined network. As a result, a transport stream corresponding to a predetermined network is sent to the TS separation unit 2 via the tuner 1. The TS separation unit 2 acquires actual-NIT and other-NIT from the transport stream and stores them in the memory 3.
[0019]
Next, it is determined whether there is another network that has not acquired actual-NIT and other-NIT (step 2).
[0020]
If there are other networks that have not obtained actual-NIT and other-NIT, switch the transponder sequentially (Step 3) to obtain actual-NIT and other-NIT sent from other networks. (Step 1).
[0021]
When actual-NIT and other-NIT are obtained from all networks, service change information table storing service change information for all networks and service switching without user network switching operation A service table is created (step 4). Thereafter, the normal operation is performed.
[0022]
As shown in FIG. 3, the service table is a table that stores service numbers for all networks and networks corresponding to the service numbers. In this example, service numbers 101 to 105 are service numbers for network A, and service numbers 111 to 115 are service numbers for network B.
[0023]
When the user inputs the service number, the CPU 9 can recognize the network corresponding to the service number input from the service table, so that the user can enter the service number without switching the network. The corresponding program can be received.
[0024]
FIG. 4 shows actual-NIT acquisition processing performed by the CPU 9 during normal operation.
[0025]
When the actual-NIT acquisition timing comes (step 11), the actual-NIT is acquired (step 12). That is, the CPU 9 outputs an actual-NIT acquisition command to the TS separation unit 2 at the actual-NIT acquisition timing. When receiving the actual-NIT acquisition command, the TS separation unit 2 acquires the actual-NIT from the currently received transport stream and stores it in the memory 3.
[0026]
Next, the actual-NIT for the currently received network acquired this time is compared with the actual-NIT for the same network acquired last time (step 13). If the service of the currently received network has been changed, The CPU 9 updates the service table according to the changed information (step 14).
[0027]
FIG. 5 shows other-NIT acquisition processing performed by the CPU 9 during normal operation.
[0028]
When the other-NIT acquisition timing comes (step 21), the other-NIT is acquired (step 22). That is, the CPU 9 outputs an other-NIT acquisition command to the TS separation unit 2 at the other-NIT acquisition timing. When receiving the other-NIT acquisition command, the TS separation unit 2 acquires other-NIT from the currently received transport stream and stores it in the memory 3.
[0029]
Next, the service change information included in the other-NIT acquired this time is compared with the service change information table, and if there is newly added service change information, that information is added to the service change information table. (Step 23).
[0030]
FIG. 6 shows a service table update processing procedure based on service change information performed by the CPU 9 during normal operation.
[0031]
When the current time information is acquired (step 31), it is determined whether the valid time of any service change information in the service change information table matches the current time (step 32).
[0032]
If the current time does not match the valid time of any service change information, the process returns to step 31. If the current time matches the valid time of any service change information, the service table is updated according to the corresponding service change information (step 33). Then, the service change information is deleted from the service change information table (step 34).
[0033]
【The invention's effect】
According to the present invention, it is possible to switch a service across networks without the user performing a network switching operation.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an electrical configuration of a digital broadcast receiver.
FIG. 2 is a flowchart showing an initial service table creation processing procedure performed by the digital receiver when power is turned on.
FIG. 3 is a schematic diagram illustrating an example of a service table.
FIG. 4 is a flowchart showing an actual-NIT acquisition processing procedure performed by a CPU 9 during normal operation;
FIG. 5 is a flowchart showing the other-NIT acquisition processing procedure performed by the CPU 9 during normal operation;
FIG. 6 is a flowchart showing a service table update processing procedure based on service change information performed by a CPU 9 during normal operation.
[Explanation of symbols]
1 Tuner 2 TS Separation Unit 3 Memory 4 On-Screen Generation Unit 5 Video Processing Unit 6 Audio Processing Unit 9 CPU
10 Image composition part

Claims (1)

In a digital TV broadcasting system that provides services from multiple networks,
For each network, the transmission specifications of its own network and the service number of each transponder that constitutes its own network are transmitted as actual-NIT, as well as the transmission specifications of other networks and the current Service change information consisting of information about services on other networks that are added, deleted or changed later and information about the effective time at which additions, deletions or changes are valid are sent as other-NIT,
When the power is turned on, the receiver receives the actual-NIT and other-NIT transmitted for each network, stores transmission specifications for all networks, and stores service change information for all networks. Means for creating a service change information table and a service table storing service numbers for all networks and networks corresponding to the service numbers;
Means for selecting a program corresponding to the service number by recognizing the network corresponding to the input service number based on the service table when the user inputs the service number;
When receiving a service provided by a network, the actual-NIT sent from the network is periodically acquired. If the acquired actual-NIT is updated, the acquired actual-NIT is updated. Means to update the service table based on NIT,
When it is necessary to periodically acquire the other-NIT sent from the network and update the service change information table when receiving a service provided by a network, the service change information table And when the current time matches the valid time of any service change information in the service change information table, the service table is updated based on the service change information whose valid time matches the current time. means,
A digital television broadcasting system characterized by comprising:

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