JP2001094519A - Method and device for digital broadcast reception - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital broadcast reception device having flexible constitution applicable to various receiving terminals. SOLUTION: A stream control part 15 controls a demultiplexer part 9 to filter broadcast data in 2nd format out of broadcast data in 1st format and outputs the broadcast data in 2nd format from the demultiplexer part 9 to an IP datagram generation part 11. The generation part 11 is controlled to read in the broadcast data in 2nd format and generate broadcast data in 3rd format by performing a specific stream processing for the broadcast data in 2nd format. The broadcast data in 3rd format are outputted from the generation part 11 to a LAN I/F part 13, which is controlled to convert the data into a data format matching the kind of a LAN 5, so that the data are sent to a PC terminal having made a reception request through the LAN 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital broadcast receiving method and apparatus required for a terminal on a network (hereinafter referred to as "receiving terminal") to receive digital broadcast information.

[0002]

2. Description of the Related Art Conventionally, in a digital broadcast receiving apparatus, a PC board type built into a board (PC board) of a personal computer (PC), which is a receiving terminal, and a data output port of the apparatus. There is known a data output port direct connection type in which the above-described device and a PC are connected one-to-one through a PC.

[0003]

In the above-mentioned conventional digital broadcast receiving apparatus of the PC board type, since the apparatus is incorporated in a PC, the apparatus configuration is a PC operating system (OS). ) And a model, etc., so that it is difficult to create an apparatus having a versatile configuration.
On the other hand, in the type directly connected to the data output port,
In order to connect one-to-one with a PC via a data output port, there is a problem that the same number of devices as the number of PCs must be installed. In addition, there is a problem that an interface dedicated to the data output port must be set in each PC as a receiving terminal.

Accordingly, an object of the present invention is to provide a digital broadcast receiving apparatus having a versatile configuration so as to be applicable to various terminals.

Another object of the present invention is to eliminate the need for installing a digital broadcast receiving apparatus in accordance with the number of terminals installed, and to provide a digital broadcast receiving apparatus without setting an interface dedicated to the digital broadcast receiving apparatus in the terminal. Is to be able to receive

[0006]

A digital broadcast receiving apparatus according to a first aspect of the present invention is required for a receiving terminal on a network to receive digital broadcast information. Means for extracting digital broadcast information in response to a reception request from a terminal, and means for converting the extracted digital broadcast information into an information format that can be transferred to the terminal through a network. Transfer the broadcast information to the terminal.

According to the above arrangement, digital broadcast information corresponding to a reception request from a terminal is extracted from the received digital broadcast information, and the extracted digital broadcast information is converted into an information format that can be transferred to the terminal via a network. Therefore, the present invention can be applied to various terminals. Also, it is not necessary to install digital broadcast receiving apparatuses according to the number of installed terminals. Further, the terminal can receive the digital broadcast without setting the interface dedicated to the digital broadcast receiving device in the terminal.

[0008] In a preferred embodiment according to the first aspect of the present invention, the digital broadcast information is time-division multiplexed digital data including character information, image information, and audio information. This digital broadcast information is broadcast from broadcasting equipment using satellite waves or terrestrial waves as a medium. The conversion means converts the extracted digital broadcast information into an IP datagram. An IP datagram contains in its header field:
In addition to the IP header and the UDP header, a unique header may be further included for exchanging necessary information with the terminal. In addition, the IP datagram includes, in its data field, digital broadcast information corresponding to a reception request from the terminal. In the above embodiment, management of transmission / stop of digital broadcast information to a terminal is performed using a multicast address and a destination port number for each digital broadcast information desired to be received. In another embodiment, an IP datagram is transmitted by broadcast, and management for transmission / stop to a terminal is performed using a destination port number for each digital broadcast information.

A digital broadcast receiving method according to a second aspect of the present invention is required for a terminal on a network to receive digital broadcast information. A first step of extracting the corresponding digital broadcast information, a second step of converting the extracted digital broadcast information into an information format that can be transferred to a terminal through a network, and a step of converting the converted digital broadcast information. , A third process for transferring to the terminal.

[0010] A program medium according to a third aspect of the present invention is necessary for a terminal on a network to receive digital broadcast information, and responds to a reception request from the terminal based on the received digital broadcast information. Means for extracting digital broadcast information, and means for converting the extracted digital broadcast information into an information format that can be transferred to a terminal through a network, and transmitting the converted digital broadcast information to a terminal. A computer program for causing a computer to operate as each of the above-described units in the broadcast receiving apparatus is readable by a computer.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing an information communication system including a digital broadcast receiving apparatus (receiving apparatus) according to one embodiment of the present invention.

As shown in FIG. 1, the system includes one receiving device 1, a plurality of receiving terminals 31 to 3n,
(Local area network) 5.

The receiving apparatus 1 receives a digital broadcast and converts the received broadcast format data into an IP (Internet Protocol) datagram which is a general-purpose interface. Next, an IP multicast address and a destination port number are given to the IP datagram according to a certain rule, and then the IP multicast address and the destination port number are transmitted to each of the receiving terminals 31 to 3n via the LAN 5. After that, only the streams (broadcast programs; the same applies hereinafter) requested by the receiving terminals (31 to 3n) are extracted from the data broadcast and transferred to the LAN 5 side.

In this embodiment, the receiving terminals 31 to 3n include:
A personal computer terminal (hereinafter referred to as a PC terminal) is used for each. Since each of the PC terminals 31 to 3n has the same internal configuration and function, the configuration and functions thereof will be described in detail in FIG.
Detailed description of the configuration and functions of the terminals (32 to 3n) is omitted.

FIG. 2 is a functional block diagram showing the internal configuration of the receiving apparatus 1 shown in FIG. 1, and FIG. 3 is a functional block showing the internal configuration of each of the PC terminals 31 to 3n connected to the receiving apparatus 1 via the LAN 5. FIG.

As shown in FIG. 2, the receiving apparatus 1 includes a tuner unit 7, a demultiplexer unit 9, an IP datagram generation unit (generation unit) 11, a LAN interface (LAN I / F) unit 13, A stream control unit (control unit) 15 and a management table 17 are provided.

The tuner 7 tunes the received time-division multiplexed broadcast data, demodulates the first-format broadcast data (multiplexed broadcast data), and demultiplexes the first-format broadcast data. Output to the unit 9. The demultiplexer unit 9 receives the multiplexed broadcast data (that is, the first format broadcast data) from the tuner unit 7 under the control of the control unit 15, and demultiplexes the PC terminals 31 to 3 from the broadcast data. 3n users filter and extract the second format broadcast data desired to be received. Then, the extracted broadcast data of the second format is output to the generation unit 11.

Under the control of the control unit 15, the generation unit 11 inputs the second format broadcast data from the demultiplexer unit 9 and performs predetermined processing on the second format broadcast data to perform the second process. Generate broadcast data in three formats. Then, the broadcast data of the third format is transmitted to the LAN I / F unit 1.
Output to 3. Here, the broadcast data of the third format is an IP multicast datagram that can be transmitted from the receiving device 1 (the LAN I / F unit 13 described below) to each PC terminal (31 to 3n) via the LAN 5. It is.
The above-described broadcast data of the first to third formats will be described in detail with reference to FIG.

The LAN I / F unit 13 includes the control unit 1
PC terminal (31-3n) through LAN5 under the control of 5
When a reception request for a specific stream is transmitted from the side, it is received. The reception request is read from the LAN I / F unit 13 by the control unit 15. LAN
The I / F unit 13 also notifies, via the LAN 5, the PC terminal that has issued the new reception request of the notification information on the multicast address and the destination port number output from the control unit 15. The LAN I / F unit 13 also receives the broadcast data of the third format from the generation unit 11 and converts it into a format according to the type of the LAN 5, for example, LAN
If 5 is an Ethernet, it is converted into an Ethernet packet, and the converted broadcast data is transmitted to each PC terminal (31 to 3n) through the LAN 5. The LAN I / F unit 13 further receives a stream reception release request transmitted from the PC terminals (31 to 3n) to the device 1 via the LAN 5. The reception cancellation request is also read by the control unit 15.

In the management table 17, the control unit 15 checks whether or not a stream requested to be received from one of the PC terminals 31 to 3n has already been received from another PC terminal. Is a table that is referred to. As a result of the check, when it is determined that the stream related to the reception request is the same as the one requested to be received from another PC terminal (the stream currently being transferred to the LAN 5), the multicast address corresponding to the stream is set. The control unit 15 searches the management table 17 for the destination port number. On the other hand, as a result of the check, when it is determined that the stream related to the reception request is a new stream, the multicast address and the destination port number that are not currently used are stored in the management table 1 by the control unit 15.
Written in 7. When any one of the PC terminals 31 to 3n issues a reception release request for a certain stream,
The control unit 15 deletes all or part of the data relating to the stream written in the management table 17 or sets a stop flag at a corresponding position in the management table 17.

First, the control unit 15 is connected to the LAN 5,
When a reception request for a specific stream is transmitted from the PC terminal (31 to 3n) via the LAN I / F 13, the request is read. Next, another P
It is checked with reference to the management table 17 whether the C terminal has already received a reception request (whether or not multicast transmission is being performed to each of the PC terminals (31 to 3n) via the LAN 5). As a result, if it is found that the reception request is for the same stream as the stream for which reception has been requested, the control unit 15 searches the management table 17 for a multicast address and a transmission destination port number corresponding to the stream. Then, as a multicast address and a destination port number to be transmitted, they are notified to the PC terminal that has made the new reception request through the LAN I / F 13 and the LAN 5. On the other hand, if the control unit 15 finds that the reception request is for a new stream, the control unit 15 obtains a multicast address and a destination port number that are not currently used, and allocates them to the new stream. Write to the management table 17. Thereafter, the PC terminal that has sent the new reception request is notified as the multicast address and the transmission destination port number to be transmitted through the LAN I / F 13 and the LAN 5 in the same manner as described above. Here, as a means for acquiring the multicast address, for example, there is a method using SDP (Session Description Protocol). SDP is currently IE
TF (Internet Engineering Task Force) standardization work is underway for multicast (multicast address allocation) WG.

The control unit 15 controls the demultiplexer unit 9 to filter and extract broadcast data of the second format from the broadcast data of the first format, and converts the broadcast data of the second format into a demultiplexer. The output from the unit 9 to the generation unit 11 is performed. Control unit 15
Controls the generation unit 11 to read the second format broadcast data into the generation unit 11, and the second format broadcast data
The data is subjected to predetermined stream processing so that the generation unit 11 generates the third format broadcast data. Then, the third format broadcast data is transmitted from the generation unit 11 to the LA format.
After being output to the NI / F unit 13, by further controlling the LAN I / F unit 13, it is converted into a format corresponding to the type of the LAN 5 as described above, and the converted broadcast data is transmitted to the LAN 5.
5, and is transmitted to the PC terminal that has made the reception request.

The control unit 15 includes a LAN 5 and an L
When a reception cancellation request for the stream is transmitted from the PC terminal that has made the reception request through the ANI / F 13, the request is read. Next, another P
C terminal is receiving or not (each PC through LAN5)
It is checked whether or not multicast transmission is being performed to the terminals (31 to 3n) with reference to the management table 17. As a result, when it is found that another PC terminal is receiving, the control unit 15 continues multicast transmission of the stream as it is, and when it is found that another PC terminal is not receiving, the control unit 15 transmits the stream. Of the multicast transmission is stopped. Here, as a method for determining whether or not another PC terminal receives the stream, other than the method of referring to the management table 17 described above, IGMP (Internet Group Management Protocol) Is used.

The PC terminal 31 is, as shown in FIG.
NI / F unit 19, stream processing unit 21, upper AP
23.

The LAN I / F unit 19 has substantially the same configuration as the LAN I / F unit 13 of the receiving apparatus 1 described above.
Broadcast data in a format (for example, the Ethernet packet) suitable for the type of the LAN 5 transmitted from the LAN I / F unit 13 through the N5 is received. Then, after converting it into the third format broadcast data again, it outputs it to the stream processing unit 21. The stream processing unit 21
/ F section 19, the third format broadcast data is input, and the third format broadcast data is subjected to a predetermined stream process to thereby obtain the fourth format broadcast data (the same data structure as the second format broadcast data). ) (Broadcast data of the fourth format is described in detail in FIG. 7). Then, the generated broadcast data of the fourth format is output to the upper AP 23.

The upper AP 23 selects a stream that the PC terminal 31 desires to receive from a number of streams,
An application program (hereinafter, referred to as an AP) for performing a stream process such as a process of notifying the selected stream to the receiving device 1 and a process for displaying an image (image process). An AP for stream selection is, for example, an EPG (Electronic Program Guide). In the present embodiment, the upper AP2
3 has both a stream selection function and an image processing function.
Also, the function of the higher-order AP 23 can be performed using two types of APs having an image processing function.

FIG. 4 and FIG.
FIG. 7 is an explanatory diagram showing transition of the storage contents of a management table 17 incorporated in the management table.

As shown, in the present embodiment, the management table 17 includes a stream ID storage area 17a, a multicast address storage area (address storage area) 17b,
Port number storage area 17c and receiving terminal (PC terminal)
Four storage areas of the information storage area 17d are set. When a plurality of stream ID storage areas 17a are set,
Address storage area 17b to PC terminal information storage area 17d
Are set in the same number as the set number of the stream ID storage areas 17a in association with the respective stream ID storage areas 17a. Note that the set number of the stream ID storage areas 17a described in FIGS. 4 and 5 is 3 in FIGS. 4A, 5A, and 5B for convenience of illustration and description. , FIG. 4 (B) and FIG. 4 (C), respectively, but it is assumed that a large number of the stream ID storage areas 17a are actually set.

Each time there is a request to receive a stream from any of the PC terminals (31 to 3n), the ID of the stream is written into the stream ID storage area 17a by the control unit 15. When an MPEG (international standard for moving image compression based on media) system is adopted, a stream ID, a PID (packet ID),
An identifier such as a SID (service ID) can also be used.

In each PC terminal information storage area 17d, a PC terminal identified by, for example, an IP address, etc.
Information (see FIGS. 4 and 5) for specifying the C terminal is written by the control unit 15. The control unit 15 writes the multicast address specified by the control unit 15 into the address storage area 17b. The control unit 15 writes the destination port number designated by the control unit 15 into the port number storage area 17c.

In FIG. 4A, the stream ID (0x000
For the stream with 1), (239.0.0.1) as the multicast address and (10001) as the port number
Are specified by the control unit 15, respectively. Then, the PC terminal (163.135.35.188) and the PC terminal that made a reception request for the stream (0x0001)
Two C terminals (163.135.35.190) are written. Also, for the stream having the stream ID (0x0002), (239.0.0.2) is
(10002) as the port number
5 is designated. Then, the stream (0x
0002), only one PC terminal (163.135.35.188) has been written as a PC terminal that has made a reception request. Further, for the stream having the stream ID (0x0005), (239.0.0.3) is
(10003) as the port number
5 is designated. Then, the stream (0x
0005), only one PC terminal (163.135.35.201) is written as the PC terminal that has made a reception request.

In this state, one PC terminal (163.135.3
It is assumed that a reception request for a stream having a stream ID (0x0007) has been transmitted from 5.202). FIG. 4 (A)
Since the stream ID (0x0007) is not stored in the stream ID storage area 17a, the stream is an untransmitted stream. Therefore, the control unit 15 acquires (239.0.0.4) as a new multicast address and (10006) as a new destination port number for the stream. And FIG.
As shown in (B), the new address is written in the address storage area 17b, the new destination port number is written in the port number storage area 17C, and the (163.135.35.202) is written in the PC terminal information storage area 17d. ).

Next, the contents stored in the management table 17 are shown in FIG.
In the state shown in (B), the one PC terminal (163.135.
35.202), a reception request for a stream having a stream ID (0x0001) is transmitted. FIG. 4 (B)
Since the stream ID (0x0001) is stored in one of the stream ID storage areas 17a, the stream is stored in another PC terminal, that is, the PC terminal (163.13).
5.35.188) and the PC terminal (163.135.35.190). Therefore, as shown in FIG. 4C, the control unit 15
Stream I that stores the stream ID (0x0001)
PC terminal information storage area 17 corresponding to D storage area 17a
d, as information for specifying the PC terminal (163.
135.35.202).

Next, the contents stored in the management table 17 are shown in FIG.
In the state shown in (C), the one PC terminal (163.135.
35.201), a reception release request for the stream having the stream ID (0x0005) is transmitted. FIG.
In (C), the one PC terminal (163.135.3) is stored in the PC terminal information storage area 17d corresponding to the stream ID storage area 17a storing the stream ID (0x0005).
5.201) is stored. Therefore, the stream is transmitted to any other PC terminal (the illustrated PC terminal (163.135.35.188) except for the PC terminal (163.135.35.201),
PC terminal (163.135.35.190) and PC terminal (163.135.
35.202)). Therefore, as shown in FIG. 5A, the control unit 15 stores the contents of the stream ID storage area 17a for storing the stream ID (0x0005) and the corresponding address storage area 17b to the PC terminal information storage area 17d. Delete all.

Further, the contents stored in the management table 17 are the same as those shown in FIG.
In the state shown in (A), the one PC terminal (163.135.
35.188), a reception release request for the stream having the stream ID (0x0001) is transmitted. Figure 5
In (A), the PC terminal (163.135.35.188) is stored in the PC terminal information storage area 17d corresponding to the stream ID storage area 17a storing the stream ID (0x0001).
In addition, the PC terminal (163.135.35.190) and the P
Two C terminals (163.135.35.202) are stored. Therefore, the stream is transmitted to the PC terminal (163.135.35.19).
0) and the PC terminal (163.135.35.202). In addition, both these P
When a plurality of PC terminals are stored in the PC terminal information storage area 17d in addition to the C terminal, the stream is a stream transmitted to those PC terminals. Therefore, as shown in FIG. 5B, the control unit 15 issues a request to cancel reception of the stream (0x0001) from the PC terminal information storage area 17d corresponding to the stream ID storage area 17a that stores the stream ID (0x0001). (163.
135.35.188) only.

FIGS. 6 and 7 are explanatory diagrams each showing a broadcast data format applied to an embodiment of the present invention.

The broadcast data format shown in FIG. 6A is the first format broadcast data output from the tuner unit 7 to the demultiplexer unit 9 in the receiving apparatus 1. In the broadcast data of the first format according to the present embodiment, three streams (streams 1, 2, and 3) respectively include time slots TS1 to TS1 which are positions on the time axis of the digital multiplex signal as shown in the drawing. The signal is assigned to the TS 9 and output from the tuner unit 7 to the demultiplexer unit 9.

Next, the broadcast data format shown in FIG. 6 (B) is the second format broadcast data output from the demultiplexer 9 to the generator 11 in the receiver 1. The broadcast data of the second format is based on the broadcast data of the first format shown in FIG. 6 (A), and only the time slots of the streams requested to be received by the PC terminals (31 to 3n) as receiving terminals are decoded. This is obtained by extraction in the multiplexer unit 9. In the example of FIG. 6B, since only stream 1 has been requested to be received, only the time slot of stream 1 is extracted, and the remaining time slots of streams 2 and 3 are all discarded.

Next, the broadcast data format shown in FIG. 6C is the third format broadcast data transmitted to the stream processing unit 21 through the LAN I / F unit 19 of the PC terminal 31. The broadcast data in the third format is converted into a format suitable for the type of the LAN 5 by the LAN I / F unit 13 of the receiving device 1 as described above, and the PC terminal 3
The data is received by the LAN I / F unit 19 on the first side, and is again converted into the third format broadcast data by the LAN I / F unit 19. The broadcast data of the third format is converted into broadcast data of the second format for transmitting the broadcast data of the second format output from the generation unit 11 to the LAN I / F unit 13 from the receiving device 1 to each of the PC terminals (31 to 3n). This is an IP datagram (IP multicast datagram) generated based on the header field and the data field. I
P datagram (that is, broadcast data of the third format)
In the header field, IP header and UDP
(User Datagram Protocol) header is set, and the above-mentioned stream 1 is set in the data field. The number of slots of the stream included in the data field depends on the specifications of the system such as the generation unit 11. It should be noted that each of the streams 1 to 3 shown in FIG. 6A and each of the streams 1 shown in FIG. 6B often have some kind of header. Broadcast data of the format shown in FIG. 6C (broadcast data of the third format) may be one with the data attached, or one with the data removed.

Next, the broadcast data format shown in FIG. 7A is a modified example of the broadcast data of the above-described third format (so-called third ′).
Format broadcast data). This broadcast data is shown in FIG.
This is generated by setting a unique header in addition to the IP header and the UDP header in the header field of the IP datagram shown in (C). The unique header is used between the receiving apparatus 1 and the stream processing unit 21 of the PC terminal 31 when some information needs to be exchanged, for example, start and end of various information exchanges. The unique header is deleted by the stream processing unit 21.

The broadcast data format shown in FIG. 7B is the fourth format broadcast data output from the stream processing unit 21 to the upper AP 23 in the PC terminal 31. The fourth format broadcast data is obtained by removing a header field (which may include an IP header, a UDP header, and a unique header) from the IP datagram (that is, the third format or the 3 ′ format broadcast data). This is the same as the above-described second format broadcast data. This stream data of the fourth format is processed by the stream processing unit 21 in accordance with the data type of each stream. For example, when the stream 1 is a file, the stream 1 is stored as a file. When the stream 1 is a video, the stream 1 performs a video decoding process from the stream processing unit 21.
The data is passed to MPEG1, MPEG2, or the like, which is the P, where image processing is performed.

FIG. 8 is a flowchart showing a processing operation when the receiving apparatus 1 receives a stream reception request.

In FIG. 8, when there is a stream reception request from the PC terminal (31 to 3n) (step S31),
The control unit 15 checks whether or not the stream related to the reception request has already been received from another PC terminal (step S32). as a result,
If the reception request has been made, the control unit 15
Searches the management table 17 for the multicast address and transmission destination port number assigned to the stream (step S33), and sends the received request to the PC
The terminal is notified (step S34). Then, the transmission of the corresponding stream with the above-mentioned multicast address is started (step S35), and the system enters a standby state to accept a new reception request from the PC terminal (step S36).

On the other hand, if the result of the check in step S32 is that no reception request has been made, a search is made for a multicast address and destination port number that are not currently used on the LAN 5 (step S37). Then, they are newly assigned to the stream and written in the management table 17 (step S38), and then the process proceeds to step S34.

FIG. 9 is a flowchart showing a processing operation when the receiving apparatus 1 receives a stream reception cancel request.

In FIG. 9, when there is a stream release request from the PC terminal (31 to 3n) (step S4).
1), the control unit 15 checks whether there is another PC terminal receiving the stream related to the reception release request (step S42). As a result of this check, if there is a receiving PC terminal, the control unit 1
5 continues the transmission of the stream as it is (step S43), and deletes the storage contents related to the PC terminal that has issued the reception release request from the management table 17 (step S44). Then, a standby state is set to accept a new reception request from the PC terminal (step S45).

On the other hand, as a result of the check in step S42, if there is no other PC terminal receiving the stream related to the reception cancellation request, the control unit 15 stops the transmission of the stream (step S4).
6) The above-described transmission stop processing is performed on the management table 17 (step S47), and the process proceeds to step S45.

FIG. 10 is a flow chart showing the processing operation on the PC terminal (31 to 3n) side.

In FIG. 10, first, the upper AP 23 selects a stream desired to be received by using the above-described EPG or the like (step S51), and sends a request to receive the selected stream through the stream processing unit 21 and the LAN I / F 19. The data is transmitted to the receiving device 1 (step S5).
2). Next, when a designation notification of the multicast address and the destination port number corresponding to the stream is transmitted from the receiving device 1, the stream processing unit 21
Receiving them through the ANI / F 19 (step S
53). Next, the stream processing unit 21 joins the specified multicast address and starts receiving the stream at the specified destination port (step S54). Next, when an instruction to cancel reception of the stream is given from the upper AP 23, the stream processing unit 21 stops receiving the stream from the reception device 1 via the LAN I / F 19 based on the instruction (step S55). Then, in accordance with an instruction from the upper AP 23, the stream processing unit 21
Then, a declaration to exit from the multicast address is transmitted to the receiving device 1 through the step 9 (step S56). The participation of the PC terminal (31 to 3n) to the designated multicast address means that the control unit 15
This refers to a procedure in which the PC terminals (31 to 3n) receive the multicast data at the multicast address specified using the address.

As described above, according to one embodiment of the present invention, digital broadcast data can be received by a general-purpose PC terminal by using the IP protocol. Is the model of PC terminal and O
It no longer depends on S or the like. In addition, since the receiving device 1 functions as a gateway between the broadcasting infrastructure and the LAN 5, the receiving device 1 can correspond to a plurality of PC terminals on the LAN 5 with only one receiving device 1. In addition, digital broadcasting is expected to have a dramatic increase in the number of broadcasting channels as compared to conventional analog broadcasting. Is converted to an IP datagram and transferred to the PC terminal, so that the address can be effectively used.

FIGS. 11 and 12 are explanatory diagrams showing the transition of the storage contents of the management table according to a modification of the embodiment of the present invention.

In this modification, in order to transmit broadcast data using a broadcast address, the multicast address storage area 17b set in the management table 17 in FIGS. 4 and 5 is stored in the management table 18 as shown in FIGS. It differs from the above embodiment in that it is not set.
For the stream having the stream ID (0x0007), (10004) is designated as the destination port number instead of (10006) shown in FIGS. 4 and 5 (the reason is that the unused destination The port number happens to be (1000
4)) is also different from the above embodiment.

The other points are the same as in the above-described embodiment.

That is, in FIG. 11A, the PC terminal (163.13
5.35.202), when there is a reception request for the stream with stream ID (0x0007), and in FIG. 11B, when there is a reception request for the stream with stream ID (0x0001) from the PC terminal. Part 15 is
The same processing as in the above embodiment is performed. FIG.
In (C), when the PC terminal (163.135.35.201) issues a reception release request for the stream with the stream ID (0x0005), the PC terminal (163.135.35.188) in FIG.
Also, when there is a reception release request for the stream with the stream ID (0x0001), the same processing as in the above embodiment is performed.

To perform substantially the same processing as in the above embodiment,
The storage contents of the management table 18 in FIG.
The stored contents of the management table 17 in (B) are the same except for the presence or absence of a multicast address.

FIG. 13 is a flowchart showing a processing operation when the receiving apparatus 1 according to the modification of the embodiment of the present invention accepts a stream reception request.

Here, each step shown in FIG. 13 is compared with each step shown in FIG. 8 corresponding to each step. First, step S63 in FIG. 13 is compared with step S33 in FIG. In FIG. 13, step S6
3 retrieves from the management table 18 the port number assigned to the stream for which reception was requested, whereas in FIG. 8, the multicast address and transmission destination port number assigned to the stream are retrieved from the management table 17 in step S33. The two steps differ in the search. Next, step S64 in FIG. 13 and step S34 in FIG.
Compare with In FIG. 13, while notifying the port number to the PC terminal that has made the reception request in step S64,
In FIG. 8, the two steps are different in that the multicast address and the transmission destination port number are notified to the PC terminal that has made the reception request in step S34.

Next, step S65 in FIG. 13 is compared with step S35 in FIG. In FIG. 13, step S6
The difference between the two steps is that transmission of the corresponding stream (broadcast transmission) is started by the port number at step 5, whereas transmission of the corresponding stream is started by the multicast address at step S35 in FIG.
Next, step S67 in FIG. 13 and step S3 in FIG.
Compare with 7. In FIG. 13, a destination port number that is not currently used on the LAN 5 is searched in step S67, whereas in FIG.
Both steps differ in that both the multicast address and destination port number that are not currently used on AN5 are searched.

Further, step S68 in FIG. 13 is compared with step S38 in FIG. In FIG. 13, step S6
8, the port number is newly assigned to the stream and written in the management table 18, whereas in FIG. 8, the multicast address and the destination port number are newly assigned to the stream in FIG. The two steps differ in that they are written in

Here, the processing operation shown in step S61 in FIG. 13 is the same as the processing operation shown in step S31 in FIG. 8, and the processing operation shown in step S62 is the same as the processing operation shown in step S32. The processing operation shown in step S66 is substantially the same as the processing operation shown in step S36. Note that the PC that has made the above reception request
When there is a reception release request from the terminal but another PC terminal is receiving the stream related to the reception release request, the control unit 15 determines whether the transmission of the stream is continued as it is in step S43 in FIG. Then, the broadcast transmission is continued as it is. On the other hand, other PC
If the terminal is not receiving, the broadcast transmission is stopped in the same way as the transmission of the stream is stopped in step S46 of FIG.

FIG. 14 is a flowchart showing a processing operation of the PC terminal according to a modification of the embodiment of the present invention.

Here, each step shown in FIG. 14 is compared with each step shown in FIG. 10 corresponding to each step. First, step S73 in FIG.
Compare with step S53 of 0. In FIG. 14, the receiving device 1 transmits a destination port number designation notification to the stream to which any one of the PC terminals (31 to 3n) has requested to receive in step S73.
The n) side receives the port number. On the other hand, FIG.
In step S53, the receiving device 1 sends a notification of the designation of the multicast address and the destination port number to the stream requested to be received in step S53, and the PC terminals (31 to 3n) receive them. In other words, the two steps are different in that the received information is the notification of the designation of the destination port number or the notification of the designation of the multicast address and the destination port number.

Next, step S74 of FIG. 14 and FIG.
Is compared with step S54. In FIG. 14, the PC terminal starts receiving (broadcast reception) the stream for which the above-mentioned reception request has been made with the transmission destination port number specified in step S74. In contrast, in FIG. 10, the PC terminal joins the specified multicast address group and starts receiving the stream with the specified destination port number. Both steps differ in the above respects. Note that the processing operation shown in step S71 of FIG.
0 and the processing operation shown in step S72 are substantially the same as the processing operation shown in step S52. Further, the processing operation shown in step S75 of FIG.
And the processing operation shown in step S76 are substantially the same as the processing operation shown in step S56.

The contents described above relate only to one embodiment of the present invention and its modifications, and needless to say that the present invention is not limited to only the above contents.

[0066]

As described above, according to the present invention,
A digital broadcast receiving apparatus having a versatile configuration can be provided so as to be applicable to various receiving terminals.

Further, according to the present invention, it is not necessary to install a digital broadcast receiving apparatus according to the number of receiving terminals installed, and the receiving terminal can be set up digitally without setting an interface dedicated to the digital broadcast receiving apparatus. A broadcast can be received.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an information communication system including a digital broadcast receiving device according to an embodiment of the present invention.

FIG. 2 is a functional block diagram showing an internal configuration of the digital broadcast receiving device shown in FIG.

FIG. 3 is a functional block diagram showing an internal configuration of each receiving terminal connected to the digital broadcast receiving device.

FIG. 4 is an explanatory diagram showing transition of storage contents of a management table incorporated in the digital broadcast receiving apparatus.

FIG. 5 is an explanatory diagram showing transition of storage contents of a management table incorporated in the digital broadcast receiving device.

FIG. 6 is an explanatory diagram showing a broadcast data format applied to one embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a broadcast data format applied to one embodiment of the present invention.

FIG. 8 is a flowchart showing a processing operation when the digital broadcast receiving apparatus receives a stream reception request.

FIG. 9 is a flowchart showing a processing operation when the digital broadcast receiving apparatus receives a stream reception release request.

FIG. 10 is a flowchart showing the processing operation of the receiving terminal.

FIG. 11 is an explanatory diagram showing transition of the storage contents of a management table according to a modification of the embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a transition of storage contents of a management table according to a modification of one embodiment of the present invention.

FIG. 13 is a flowchart showing a processing operation when a digital broadcast receiving apparatus according to a modification of the embodiment of the present invention accepts a stream reception request.

FIG. 14 is a flowchart showing a processing operation of a receiving terminal according to a modification of one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Digital broadcast receiving apparatus (receiving apparatus) 31-3n Receiving terminal (PC terminal) 5 LAN (local area network) 7 Tuner section 9 Demultiplexer section 11 IP datagram generating section (generating section) 13, 19 LAN interface section (LAN I / F
Unit) 15 stream control unit (control unit) 17 management table 21 stream processing unit 23 upper AP

Continued on the front page F term (reference) 5K028 BB05 KK03 MM05 SS11 SS24 TT05 5K030 HB02 HC14 JL02 KA02 LB16 LD07 9A001 BB01 BB03 BB04 CC05 CC06 CC07 CC08 DD06 EE02 EE04 FF03 HH27 HH30 KK15 KK31

Claims (8)

[Claims] An apparatus necessary for a terminal on a network to receive digital broadcast information, comprising: means for extracting digital broadcast information in response to a reception request from the terminal from received digital broadcast information; Means for converting the extracted digital broadcast information into an information format transferable to a terminal via a network, wherein the digital broadcast information after the conversion is transferred to the terminal. 2. The digital broadcast receiving apparatus according to claim 1, wherein the digital broadcast information is broadcast from a broadcast facility using a satellite wave or a terrestrial wave as a medium. 3. The apparatus according to claim 1, wherein the converting means converts the extracted digital broadcast information into
Digital broadcast receiving device that converts to IP datagram. 4. The apparatus according to claim 3, wherein the IP datagram includes an I datagram in a header field thereof.
A digital broadcast receiving apparatus that may include a unique header for transmitting and receiving necessary information to and from a terminal in addition to a P header and a UDP header. 5. The digital broadcast receiving apparatus according to claim 3, wherein the IP datagram includes in its data field digital broadcast information corresponding to a reception request from a terminal. 6. The apparatus according to claim 1, wherein the management of the transmission / stop of the digital broadcast information to the terminal is performed by setting a multicast address and a destination port number for each digital broadcast information desired to be received. Digital broadcast receiving device performed using. 7. The apparatus according to claim 1, wherein the IP datagram is transmitted by broadcast, and management for transmission / stop to the terminal is performed only by a transmission destination port number for each digital broadcast information. Digital broadcast receiving device performed using. 8. A device necessary for a terminal on a network to receive digital broadcast information, comprising: means for extracting digital broadcast information in response to a reception request from the terminal from the received digital broadcast information; Means for converting the extracted digital broadcast information into an information format that can be transferred to a terminal via a network, wherein the digital broadcast information after the conversion is transferred to the terminal. A computer-readable program medium carrying a computer program for operating a computer as each of the above means.