JP2003229906A - Transport stream processing apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To insert or replace a packet in an optimal timing when replacing the packet during recording of digital broadcast. <P>SOLUTION: When a transport stream is inputted, processing to that packet is determined by a packet identifier applied to the packet by a packet identification circuit 101. When a CPU 1 produces a packet to be newly outputted, stores it in a packet processing instruction circuit 103 and instructs the insertion of the packet, a stream output circuit 104 searches for a packet judged to be discarded by the packet identification circuit 101 and inserts the new packet to that position. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION When a digital broadcast is received and recorded on a digital VTR or a hard disk device, unnecessary packets in the input transport stream are discarded, or a specific packet is newly created. The present invention relates to a circuit for replacing or inserting a new packet and outputting a transport stream.

[0002]

2. Description of the Related Art In recent years, digital broadcasting has become common, and there is an increasing demand for recording received data in a digital VTR, a hard disk device or the like.

In digital broadcasting, a transport stream defined in the MPEG2 system standard, which is an international standard, is used as the data structure and data multiplexing method. Generally, a plurality of programs are multiplexed in one transport stream. Is broadcasting. The transport stream is composed of fixed-length packets called transport stream packets, and a packet identifier called PID is assigned to each transport stream packet to indicate the type of data stored in the packet. For example, when two programs, program A and program B, are multiplexed, individual PIDs are assigned to packets storing the video of program A, the audio of program A, the video of program B, and the audio of program B, respectively. Has been. In addition to data such as video and audio, the transport stream also contains information such as PID allocation table, program table and program content necessary for program selection such as which program video and audio is allocated to which PID. It is necessary to multiplex and transmit various information such as user-specific information. Although a defined data format called a section is used for transmitting these pieces of information, section format data is also stored in the transport stream packet, and a PID is assigned to each piece of information.
The transport stream multiplexes a plurality of programs by multiplexing these packets.

Next, a case will be described in which one or more specific programs are selected from a transport stream in which a plurality of received programs are multiplexed and recorded in an external device such as a digital VTR.

When digitally recording a digital broadcast,
Generally, the transport stream format is used,
It is not necessary to record all of a plurality of multiplexed programs or information in order to record and reproduce a specific program. On the contrary, since recording all programs and information leads to an increase in recording band, only the program containing the program to be recorded and the packet containing the information necessary to reproduce the program are recorded by the PID described above. A method of selecting and discarding unnecessary packets and recording them is adopted. However, if unnecessary packets are discarded, in the output transport stream, information inconsistency will occur between the packets that make up the transport stream and the packets that contain program information, etc. Must be recorded. Specifically, PMT (Pr that specifies the PID of the packet that transmits each coded signal that constitutes the broadcast program)
program map table (PAT), which specifies the PID of the packet that transmits the PMT (Program)
An Association Table) is newly created, and the PMT and PAT of the input stream are replaced and output. In addition, a packet SIT (Selection Inf) including a summary of information necessary for providing information of a transport stream to be transmitted.
NIT (Network Information), which is an unnecessary packet that can discard the operation table.
(Tion Table) is replaced and output.

As described above, when a transport stream received from a broadcast is recorded on a digital VTR or the like, there are some packets that do not need to be recorded.
It is necessary not to output this, and for a certain packet, the packet is replaced and output.

A conventional packet processing device for replacing these packets is, for example, Japanese Patent Laid-Open No. 11-2391.
No. 75 publication. FIG. 6 is a block diagram of a conventional packet processing device. In FIG. 6, 6
Reference numeral 01 is a replacement data storage unit, 602 is a packet determination unit, 603 is a packet assembly unit, and 604 is a packet replacement unit.

The operation of the conventional packet processing device configured as described above will be described. The replacement data storage unit 601 stores the PI of the packet to be replaced.
The replacement data constituting the replacement packet after replacement with D is associated and stored. These data are
It is set by the CPU, and the figure shows that two sets of replacement data and a replacement target PID are set. The packet determination unit 602 determines whether or not the packets forming the input transport stream match any of the replacement target PIDs set in the replacement data storage unit 601, and if they match, Is a packet assembling unit 603 and a packet replacing unit 60.
No. 4 is notified of the agreement. Packet assembly unit 603
Upon receipt of the notification of coincidence from the packet determination unit 602, the corresponding replacement data is read from the replacement data storage unit 601 and a packet for replacement is assembled. The packet replacement unit 604 uses the packet determination unit 60.
When the notification of matching is received from 2, the packet assembling unit 603 outputs the assembled packet, and when the matching is not notified, the packet determining unit 602 outputs the input packet as it is to the outside.

In this way, when the PID of the packet forming the input transport stream matches the PID set in the replacement data storage unit 601, the packet is replaced with the newly assembled packet and output. Packet replacement is achieved by.

FIG. 7 is a conceptual diagram showing an example of packet processing output in a conventional packet processing device. Packet processing and transport stream output during digital recording in the conventional packet processing apparatus will be described with reference to FIG. For simplification, the input transport stream is two programs, program A and program B, and 1
It is assumed that one piece of information, information C, is multiplexed. At this time, the video and audio of the program A, that is, the video A, the audio A, and the program B
An individual PID is assigned to each of the packets including the video B and the audio B, which are the video and the audio, and the information C. A case where only the program A is recorded on the digital VTR from the transport stream will be described. When recording the program A, in addition to the packet containing the video A and the audio A, the packet containing the information D newly created to be suitable for the stream to be recorded based on the data of the information C must be recorded. I shall. Further, the information C included in the input stream has a data size that spans two packets, and the packets of the information C-1 and the information C-2 are repeatedly transmitted, while the data size of the newly created information D is It shall fit in one packet. At this time, in the conventional packet processing device, since the packet to be replaced is specified by the PID, the packet D including the information C in the input stream is newly created.
Will be replaced with the packet containing the information C-1 and the packet of the information C-1 and the information C-2 will always be replaced.

[0011]

However, since the conventional packet processing device specifies the packet to be replaced by the PID in the input stream when the packet is replaced, the replacement timing is the packet in the input stream. It will depend on the placement. For example,
NIT as information C and newly created SI as information D
When T, that is, SIT is the NI of the input stream
When substituting for T, the output timing of the SIT depends on the position of the NIT in the input stream and cannot be output at the optimal timing for the newly created SIT. In addition, as the information C, the PMT of the input stream, and as the information D, the newly created PMT
When a packet including a new PMT is created and replaced with the original packet, if the number of packets required to accommodate the newly created PMT is smaller than that of the input stream, When the PMT of the stream is replaced every time, packets including the same data are repeatedly output more than necessary.

The present invention solves the conventional problems as described above, and instead of designating the PID of the input stream as the packet to be replaced, a new packet is created at an arbitrary timing. A transport stream that inserts packets or specifies the PID of the input stream as the packet to be replaced, and controls the packet replacement frequency in response to this to replace or insert packets at appropriate timings. An object is to provide a processing device.

[0013]

In order to achieve this object, a transport stream processing apparatus according to claim 1 of the present invention inputs a transport stream in which data of a plurality of programs are multiplexed in packet units. A packet identification circuit that divides the packet and sets a process for the packet according to the packet identifier assigned to the packet and outputs an identification result and the packet; and inputs the identification result and the packet, and includes the packet in the packet. A packet analysis circuit that analyzes data to extract necessary data, a packet processing instruction circuit that outputs a designated packet based on the identification result and an instruction from the CPU to instruct processing of the designated packet, the identification result and the According to the instruction of the packet processing instruction circuit, the packet and the designated packet are output. To control the operation and has a configuration with a stream output circuit for outputting as a new transport stream. In the transport stream processing device according to claim 2 of the present invention, in the configuration according to claim 1, the packet processing instruction circuit includes a packet storage circuit that stores the designated packet, the identification result, and the CPU. In accordance with the instruction of 1., an insertion control circuit for instructing the insertion of the designated packet is provided. Also, in the transport stream processing device according to claim 3 of the present invention, in the configuration according to claim 1, the packet processing instruction circuit includes a packet storage circuit that stores the designated packet, the identification result, and the CPU. In accordance with the instruction, the replacement control circuit that gives an instruction to replace the designated packet is provided.
Further, the transport stream processing method according to claim 4 of the present invention inputs a transport stream in which data of a plurality of programs is multiplexed in packet units, divides the packet into packets, and uses a packet identifier assigned to the packet. A packet identification process that sets a process for the packet and outputs the identification result and the packet, a packet analysis process that analyzes the data included in the packet using the identification result to extract necessary data, and a packet An instruction process for storing the designated packet in the previous period by writing it in the storage means, outputting the designated packet stored in the packet storage means based on the identification result and the instruction from the CPU, and giving an instruction for processing the designated packet. And output of each packet according to the identification result and the instruction of the instruction processing. Controls work comprises a process of creating a new transport stream.

[0014]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing a part of the configuration of a transport stream processing apparatus and a digital broadcast receiver including the transport stream processing apparatus according to the first embodiment of the present invention. Is shown. In FIG. 1, 10 is a transport stream processing device of the present invention, 101 is a packet identification circuit, 10
2 is a packet analysis circuit, 103 is a packet processing instruction circuit, 104 is a stream output circuit, 1 is a CPU,
Reference numeral 2 is a memory, 3 is an AV decoder, and 4 is a CPU bus, which together with the transport stream processing device 10 constitute a digital broadcast receiver. As the output of the digital broadcast receiver, a transport stream for recording is sent from the stream output circuit 104 to the recording device,
An AV signal is output from the AV decoder 3 to a monitor or the like. In the figure, in the arrows relating to the inside and the input / output of the transport stream processing device 10, the thick line indicates the flow of packet data, the thin line with the CPU bus 4 indicates the flow of data or control signals, and the other thin lines. Indicates the flow of control signals. The operations of the transport stream processing device and the digital broadcast receiver configured as described above will be described.

The transport stream input to the transport stream processing device 10 is input to the packet identification circuit 101. The packet identification circuit 101 divides the packet in packet units by detecting the boundaries of the packets in the transport stream, and has a table for setting information regarding the packet and processing for the packet for each PID. The type of information included is identified and the process for the packet of each PID is set. When recording digitally,
The types of processing of each packet in the output include outputting the input packet as it is, replacing it with a new packet and outputting it, or discarding it and not outputting it. The packet analysis circuit 10 in the latter stage after setting the processing
2. The packet processing instruction circuit 103 and the stream output circuit 104 are output as identification results and the respective packet data are output.

The packet analysis circuit 102 extracts only the actually required data from each packet in accordance with the instruction from the packet identification circuit 101 and transfers it to the memory 2.
This data corresponds to video and audio data of a program to be viewed and various information data. The video and audio data of the program to be viewed is transferred from the memory 2 to the AV decoder 3 in accordance with a request from the AV decoder 3 and subjected to decompression processing and then output to a display device or the like. On the other hand, various information data are taken out by the CPU 1 and used for controlling the digital broadcast receiver.

The packet processing instruction circuit 103 includes a CPU 1
The packet created by or is stored as a designated packet, and the packet output operation is performed to the stream output circuit 104 according to the instruction from the CPU 1 and the identification result of the processing of each packet input from the packet identification circuit 101. Control and output packet data. The packet data may be output when the stream output circuit 104 makes a request.

The stream output circuit 104 inputs each packet output from the packet identification circuit 101 and the packet processing instruction circuit, and also the packet identification circuit 10
1 and the packet processing instruction circuit 103, the identification result and the processing instruction for each packet are input, and the output operation of the packet is controlled according to these control signals to create and output a new transport stream. The transport stream output from the stream output circuit 104 is recorded in the recording device.

FIG. 2 is an example showing a block diagram of the configuration of the packet processing instruction circuit 103 in FIG. 1, and the transport stream processing device in this case will be described below. In FIG. 2, 201 is a packet storage circuit, and 202
Is an insertion control circuit. The packet storage circuit 201 stores a designated packet, and the CPU 1 in FIG.
Is created from the information data stored in the memory 2 and stored in the packet storage circuit 201. Alternatively, predetermined fixed data may be stored in the packet storage circuit 201 as a designated packet. The insertion control circuit 202 is the CPU 1 of FIG.
From the packet insertion instruction and the identification result input from the packet identification circuit 101, the stream output circuit 104 is caused to insert the packet stored in the packet storage circuit 201 into the packet determined to be discarded by the packet identification circuit 101. Send instructions. At this time, the stream output circuit 104 receives the identification result of discarding the packet from the packet identification circuit 101, but the insertion control circuit 2
In response to the packet insertion instruction from 02, the designated packet stored in the packet storage circuit 201 is inserted and output.

FIG. 3 is a conceptual diagram showing an example of packet processing output in the transport stream processing apparatus of this embodiment. The operation of creating a new transport stream will be described with reference to FIG. 1 and this conceptual diagram. In this example, a case will be described in which a transport stream in which program A and program B and information C as information data are multiplexed is input and only program A is recorded. In this case, the packet identification circuit 101 determines that it is necessary to output the packet including the video A and the audio A that form the program A, and outputs the identification result that is output as it is. Also, the video B that constitutes program B
The packet including the voice B is judged to be unnecessary and the discrimination result to be discarded is output. Further, it is determined that the packet including the information C is unnecessary and is output as an identification result to be discarded, but it is necessary to output the packet including the information D newly created by the CPU 1 as the information data. The data size of the information D does not fit in one packet and is composed of two pieces of packet information D-1 and information D-2, which are repeatedly output. Here, the packet processing instruction circuit 103 receives an instruction from the CPU 1 to insert a new packet, and further discards a packet in the input stream based on a control signal (identification result) input from the packet identification circuit 101, That is, when any packet including video B, audio B, or information C is detected, a packet insertion instruction is output to the stream output circuit 104 and packet information D to be inserted.
It outputs -1. The stream output circuit 104, which has received the insertion instruction, detects the packet to be discarded from the input stream based on the control signal input from the packet identification circuit 101, and inserts the packet information D-1 at this position. The insertion of the packet information D-1 is completed, and the CPU is restarted.
When 1 instructs the packet processing instruction circuit 103 to insert a packet, the stream output circuit 104 detects the packet to be discarded again and inserts the packet information D-2 at that position. Generally, in the packets included in the stream, the number of packets including the video and audio of the program is much larger than the packets including each information data, and some programs are selected and recorded. That is, when discarding a packet including video and audio of a program that is not selected, there are enough discarded packets necessary to insert a new packet.

As described above, according to this embodiment, a transport stream in which data of a plurality of programs are multiplexed in packet units is input, divided into packets, and the packets are assigned to the packets by the packet identifier given to the packets. A packet identification circuit that determines the processing, a packet analysis circuit that inputs the identification result of the packet identification circuit and the packet, analyzes the data contained in the packet and extracts the necessary data, and processes the newly created specified packet data. A packet processing instruction circuit for instructing and a stream output circuit for controlling the output operation of each packet according to the identification result of the packet identification circuit and the instruction of the packet processing instruction circuit and outputting as a new transport stream are further provided. The circuit records the packet to be newly output. The packet storage circuit for storing the packet and the insertion control circuit for instructing to insert the packet stored in the packet storage circuit are discarded so that the newly created packet is discarded in the input stream. To detect the packet and insert it at that position,
The output timing does not depend on the packet arrangement in the input stream, and the output frequency can be arbitrarily controlled by the insertion instruction from the CPU. As a result, regardless of the size of the data contained in the newly created packet, the output frequency of this data must be satisfied by the frequency specified in the standards, and vice versa. It becomes possible to control so as to prevent this. The control of the output frequency can be realized by issuing an insertion instruction from the CPU 1 every predetermined time, for example.

Although one packet processing instruction circuit is provided in this embodiment, when there are a plurality of types of packets to be inserted, for example, when PAT, PMT, SIT, etc. are created and inserted as new data. If a plurality of packet processing instruction circuits are provided, a plurality of types of packets can be similarly inserted.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
The transport stream processing device in this case will be described below with reference to an example showing a block diagram of the configuration of the packet processing instruction circuit 103 in the embodiment. In FIG. 4, reference numeral 401 denotes a packet storage circuit, which stores a designated packet like the packet storage circuit 201 in FIG. Reference numeral 402 is a replacement control circuit. The replacement control circuit 402 further executes a packet for the packet determined by the packet identification circuit 101 to execute the replacement according to the packet replacement instruction from the CPU 1 of FIG. 1 and the identification result of each packet input from the packet identification circuit 101. Is discarded or the packet is discarded without being replaced, and an instruction is sent to the stream output circuit 104. That is, the P to be replaced from the CPU 1
By instructing the packet having the ID to be replaced at a predetermined frequency (for example, N for M (M and N are integers)), the replacement control circuit 402 causes the replacement target packet to be replaced by M parts from the packet to be replaced. The stream output circuit 104 is instructed to replace it with a new designated packet at a frequency of N. At this time, the stream output circuit 104 replaces the packet having the PID to be replaced according to the instruction of the replacement control circuit 402, and replaces only the packet instructed to be replaced.

FIG. 4 is a conceptual diagram showing an example of packet processing output in the transport stream processing apparatus of this embodiment. The operation of creating a new transport stream will be described with reference to FIG. 1 and this conceptual diagram. In this example, a case will be described in which a transport stream in which program A and program B and information C as information data are multiplexed is input and only program A is recorded. The information C has a data size that extends over two packets, and the information C-1 and the information C-
It is assumed that two packets are repeatedly transmitted. In this case, the packet identification circuit 101 determines that the packet including the video A and the audio A that form the program A needs to be output, and outputs the identification result so that the packet is output as it is. Further, the packet including the video B and the audio B forming the program B is determined to be unnecessary and the identification result is output so as to be discarded. Further, it is determined that the packet including the information C needs to be replaced with the packet including the information D,
The CPU 1 instructs to replace the designated packet with the newly created information D and output the designated packet. Here, the data size of the newly created information D fits in one packet. At this time, the CPU 1 instructs the packet processing instruction circuit 103 to replace the packet including the information D in the input stream with the frequency of ½ of the packet. Packet processing instruction circuit 10
When the CPU 3 receives an instruction from the CPU 1 to replace the packet at a frequency of ½, the CPU 3 instructs the stream output circuit 104 of the reason and outputs the packet information D for the replacement. Upon receiving the replacement instruction, the stream output circuit 104 detects a packet instructed to be replaced with a new packet from the stream, that is, a packet including the information C, and executes the replacement of the packet only once for every two detections. To do. The remaining packet is discarded once in the input stream. In this way, one of the two packets containing the information C is replaced with a new packet, and one packet is discarded, thereby controlling the output frequency of the new packet.

As described above, according to this embodiment, the packet processing instruction circuit controls the packet storage circuit for storing a packet to be newly output and the frequency at which the packet storage circuit outputs the packet. With the configuration including the replacement control circuit, the frequency of replacing a packet having a specific PID to be replaced in the input stream with a newly created packet is set to CP.
It is possible for U to set and optimize the output frequency of the newly created packet. For example, when the packet to be replaced includes data having a size that spans two packets in the input stream and the data to be newly replaced and output contains data that fits in one packet,
By setting the replacement and output frequency to 1/2,
It is possible to control so as to prevent output more than necessary.

Although one packet processing instruction circuit is provided in this embodiment, when there are a plurality of types of designated packets, for example, when PAT, PMT, SIT, etc. are created and replaced as new data, packet processing is performed. If a plurality of instruction circuits are provided, the replacement frequency of a plurality of types of packets can be controlled in the same manner.

[0028]

As described above, the transport stream processing apparatus and method of the present invention are provided with a packet processing instruction circuit for processing a packet so that when a newly created designated packet is inserted By performing the packet processing specified by the PID from the packet in the stream and the packet processing instructed by the packet processing instruction circuit, the timing of the processing can be controlled without depending on the packet arrangement in the input stream. As a result, by outputting the data to be recorded without excess or deficiency, it is possible to optimize the recording band when recording the digital broadcast.

Further, the transport stream processing apparatus and method of the present invention are provided with a packet storage circuit and an insertion control circuit in the packet processing instruction circuit so that a newly created designated packet is generated from the input stream by PID.
Since the packet that is judged to be discarded by the identification of is inserted at that position, the insertion frequency does not depend on the input stream and the output frequency can be controlled arbitrarily,
Its practical effect is great.

Furthermore, the transport stream processing apparatus and method of the present invention newly provide a packet storage instruction circuit and a replacement control circuit in the packet processing instruction circuit so that a packet having a specific PID in the input stream is newly added. Since the frequency of replacement with the created designated packet is set, the output frequency of the newly created packet can be optimized, which is extremely effective in practice.

[Brief description of drawings]

FIG. 1 is a block diagram of a transport stream processing device and a digital broadcast receiver according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a packet processing instruction circuit according to the first embodiment of the present invention.

FIG. 3 is a conceptual diagram showing an example of transport stream processing according to the first embodiment of the present invention.

FIG. 4 is a block diagram of a packet processing instruction circuit according to a second embodiment of the present invention.

FIG. 5 is a conceptual diagram showing an example of a transport stream process according to the second embodiment of the present invention.

FIG. 6 is a block diagram of a conventional packet processing device.

FIG. 7 is a conceptual diagram showing an example of transport stream processing in a conventional packet processing device.

[Explanation of symbols]

1 CPU 2 memory 3 AV decoder 4 CPU bus 10 Transport stream processing device 101 packet identification circuit 102 Packet analysis circuit 103 Packet processing instruction circuit 104 Stream output circuit 201 packet storage circuit 202 Insertion control circuit 401 packet storage circuit 402 Replacement control circuit 601 Replacement data storage unit 602 packet determination unit 603 Packet Assembly Department 604 packet replacement unit

Claims (6)

[Claims] 1. A transport stream in which data of a plurality of programs is multiplexed in packet units is input, divided into packets, and a process for the packet is set by a packet identifier given to the packet, and the identification result and the A packet identification circuit that outputs a packet, a packet analysis circuit that inputs the identification result and the packet, analyzes the data included in the packet and extracts necessary data, and based on the identification result and an instruction from the CPU A packet processing instruction circuit for outputting a designated packet and instructing the processing of the designated packet, and a new transport by controlling the output operation of the packet and the designated packet according to the identification result and the instruction of the packet processing instruction circuit. A stream output circuit for outputting as a stream is provided. Transport stream processing device. 2. The packet processing instruction circuit includes a packet storage circuit that stores the designated packet, and an insertion control circuit that issues an instruction to insert the designated packet according to the identification result and the instruction from the CPU. The transport stream processing device according to claim 1, wherein 3. The packet processing instruction circuit includes a packet storage circuit for storing the designated packet, and a replacement control circuit for instructing replacement of the designated packet according to the identification result and the instruction from the CPU. The transport stream processing device according to claim 1, wherein 4. A transport stream, in which data of a plurality of programs is multiplexed in packet units, is input, divided into packets, and a process for the packet is set by a packet identifier assigned to the packet. A packet identification process for outputting the packet, a packet analysis process for analyzing the data contained in the packet using the identification result to extract necessary data, and a designated packet stored in the packet storage means to store the designated packet. An instruction process for outputting the designated packet stored in the packet storage means based on the identification result and an instruction from the CPU and instructing the processing of the designated packet; and an instruction for the identification result and the instruction process. Control the output operation of each packet according to the following, and create a new transport stream Transport stream processing method including processing for performing. 5. The processing of the designated packet in the instruction processing is to insert the designated packet into a packet determined to be discarded in the packet identification processing based on an instruction from the CPU. Transport stream processing method. 6. The processing of the designated packet in the instruction processing is to replace a packet determined to be replaced in the packet identification processing with the designated packet based on an instruction from the CPU. Transport stream processing method.