JP2010135990A - Apparatus and program for processing digital broadcast signal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a processing apparatus and a processing program which allow a digital broadcast signal to be switched in an MPEG-2 TS signal level at an arbitrary timing in a reception station. <P>SOLUTION: A digital broadcast signal processing apparatus includes a stream switching means which, when switching from one digital broadcast signal to another digital broadcast signal, removes an image frame which is included in a stream of the another digital broadcast signal and refers to an image frame before the switching during decoding, from an output signal to perform switching processing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a digital broadcast signal processing apparatus and processing program, and more particularly, to a digital broadcast signal processing apparatus and digital broadcast signal processing program for partially replacing and outputting a plurality of types of received signals.

  Conventionally, a local broadcast station broadcasts broadcast materials (referred to as programs, CMs, and the like) independently produced by the local stations and broadcast materials transmitted from the key stations for each time zone. In the case of terrestrial analog broadcasting or the like, broadcast materials can be switched by appropriately replacing and outputting a plurality of types of input analog signals in a broadcast signal processing device. The output broadcast signal is broadcast toward the viewer.

On the other hand, similarly in digital broadcasting, program organization using a plurality of types of broadcasting materials is performed. In the case of digital broadcasting, since a broadcast signal encoded and compressed by MPEG-2 or the like is used, the received signal cannot be replaced and output as it is in the case of analog broadcasting.
Therefore, conventionally, switching of broadcasting material in digital broadcasting is performed by the following method.
As a first method, an encoded broadcast signal is transmitted between broadcasting stations (between a key station and a local station), and the received signal is decoded (expanded) at a receiving station (local station), and broadcast data is transmitted. There is a method of outputting a broadcast signal which has been encoded again after the replacement.
As a second method, there is a method in which broadcast data before encoding is transmitted between broadcasting stations, and after the broadcast data is replaced at a receiving station, an encoded broadcast signal is output.
Japanese Patent Laid-Open No. 11-341492

  However, the first method has a problem that broadcast data is deteriorated by repeating encoding and decoding, and a delay occurs in broadcasting. In this regard, the second method described above does not cause deterioration or delay, but there is a problem that the communication cost for transmitting uncompressed broadcast data material between broadcast stations increases.

  In addition, with regard to the replacement process of the digital broadcast signal, for example, after replacing a part of the broadcast signal from the transmitting station at the receiving station, the first part of the replaced broadcast signal and the position behind the replacement range, respectively, A technique has been proposed in which broadcast signal replacement is performed quickly and easily by adding information on the encoding format of the local station to describe and encode the encoding format information of the local station (Patent Document 1). .

  However, in the technique described in Patent Document 1, it is necessary to recognize the replacement point of the broadcast signal between the transmitting station and the receiving station, so that the MPEG-2 TS (Transport) at an arbitrary timing on the receiving station side. Stream) The signal level cannot be replaced.

  The present invention has been made in view of such circumstances, and a digital broadcast signal processing apparatus and a digital broadcast signal processing apparatus capable of replacing a digital broadcast signal at an MPEG-2 TS signal level at an arbitrary timing in a receiving station. It is intended to provide a broadcast signal processing program.

  As a result of diligent research in view of the above problems, the present inventors refer to the image frame in the GOP immediately after the replacement point and the image frame in the GOP before the replacement point at the time of decoding when replacing the digital broadcast signal. It is conceived that the digital broadcast signal can be replaced at the MPEG-2 TS signal level without decoding and re-encoding by removing the image frame that must be performed from the output signal, and the following invention is achieved. It came to.

  That is, the present invention is a digital broadcast signal processing apparatus that partially replaces two or more input different encoded digital broadcast signal streams and outputs them as one stream of digital broadcast signals. When replacing a stream with another digital broadcast signal stream, the image frame included in the other digital broadcast signal stream and referring to the image frame at the stream position before replacement at the time of decoding is removed from the output signal. Accordingly, the present invention provides a digital broadcast signal processing apparatus having stream replacement processing means for performing replacement processing.

  The digital broadcast signal processing apparatus of the present invention further includes the time information added to the digital broadcast signal for the one digital broadcast signal in the digital broadcast signal that has been replaced by the stream replacement processing unit. It has time information conversion processing means for converting time information in the same format as time information of other digital broadcast signals.

  The digital broadcast signal processing apparatus of the present invention further includes a time stamp addition processing unit that adds a time stamp to each input digital broadcast signal in units of packets, and a digital broadcast signal that is replaced by the stream replacement processing means. On the other hand, it has a packet rearrangement processing means for adjusting a temporal arrangement of each packet based on a time stamp added to each packet of the digital broadcast signal.

  The present invention also provides a receiving means for receiving two or more different encoded digital broadcast signal streams, and a stream difference for generating one stream of digital broadcast signals by partially replacing the two or more digital broadcast signal streams. A digital broadcast signal processing program used in a digital broadcast signal processing apparatus includes: a replacement processing unit; and an output unit that outputs a digital broadcast signal of one stream generated by the stream replacement processing unit. When replacing a stream with another digital broadcast signal stream, the image frame included in the other digital broadcast signal stream and referring to the image frame at the stream position before replacement at the time of decoding is removed from the output signal. Stream replacement for replacement processing There is provided a digital broadcast signal processing program and executes a management step.

  The digital broadcast signal processing program of the present invention further includes a time added to the digital broadcast signal with respect to the one digital broadcast signal in the replaced digital broadcast signal after executing the stream replacement processing step. A time information conversion processing step for converting the information into time information in the same format as the time information of the other digital broadcast signal is performed.

  The digital broadcast signal processing program according to the present invention further executes a time stamp addition processing step of adding a time stamp in packet units to each input digital broadcast signal before executing the stream replacement processing step. After executing the replacement processing step or after executing the time information conversion processing step, the replacement of the digital broadcast signal is performed on the basis of the time stamp added to each packet of the digital broadcast signal. A packet rearrangement process for adjusting temporal arrangement is executed.

As described above, according to the digital broadcast signal processing apparatus and the digital broadcast signal processing program of the present invention, when a digital broadcast signal is replaced, it is an image frame in a GOP immediately after the replacement point and is replaced at the time of decoding. By removing an image frame that must refer to an image frame in the previous GOP from the output signal, the digital broadcast signal can be replaced at the MPEG-2 TS signal level without decoding and re-encoding. It is possible.
In broadcasting stations, etc., broadcast materials consisting of encoded digital broadcast signals can be replaced and broadcast without decoding and re-encoding, so the number of equipment and man-hours can be reduced, and space can be secured. It can be expected to reduce running costs, reduce equipment to be monitored, and improve failure rate.

  The best mode for carrying out a digital broadcast signal processing apparatus and a digital broadcast signal processing program according to the present invention will be described below in detail with reference to the accompanying drawings. FIGS. 1-12 is a figure which illustrates embodiment of this invention, In these figures, the part which attached | subjected the same code | symbol represents the same thing, and the fundamental structure and operation | movement are the same. To do.

<Configuration>
A configuration of a digital broadcast signal processing apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram schematically showing an internal configuration of a digital broadcast signal processing apparatus according to the present embodiment.
In FIG. 1, the digital broadcast signal processing apparatus of this embodiment includes a TTS unit 110 that adds a time stamp to an MPEG-2 TS packet included in a received signal to form a TTS (Timestamped TS) packet, and an MPEG-2 TS packet. Information replacement unit 111 that replaces the ES (Elementary Stream) portion, which is the data portion of the data, and time information conversion that converts the time information of one ES portion to match the other according to the replacement of the ES portion of the MPEG-2 TS packet The processing unit 112 includes a TS placement unit 113 that places the replaced MPEG-2 TS packet at a predetermined temporal position to form an output packet. The digital broadcast signal processing apparatus according to the present embodiment includes a CPU, a RAM, a ROM, other storage units, and an I / O unit.

<Operation>
In the digital broadcast signal processing apparatus 100 configured as shown in FIG. 1, two types of input digital broadcast signals (MPEG-2 TS signals) are appropriately partially decoded without being decoded and re-encoded. It is replaced and output as one type of digital broadcast signal.
Hereinafter, details of processing of each functional unit in the digital broadcast signal processing apparatus 100 will be described.

FIG. 2 is a sequence diagram showing an outline of the overall operation of the digital broadcast signal processing apparatus 100.
As illustrated in FIG. 2, the digital broadcast signal processing apparatus 100 performs TTS processing by the TTS unit 110, ES replacement processing by the ES replacement unit 111, and time information conversion processing unit 112 for the input digital broadcast signal. The signal obtained by sequentially performing the time information conversion process by the TS and the TS arrangement process by the TS arrangement unit 113 is output as the replaced digital broadcast signal.

  FIG. 3A is a diagram showing an overview of the TTS processing by the TTS unit 110 of the digital broadcast signal processing apparatus 100. As shown in the figure, the MPEG-2 TS as an input signal is configured as a stream in which a PCR (Program Clock Reference) packet including transmission-side reference time information is inserted between TS packets. The transmission rate of MPEG-2 TS can be calculated by counting the transmission interval (Δt1) and the number (N) of TS packets included therein.

FIG. 3B is a flowchart showing in detail the flow of processing performed by the TTS unit 110.
3B, the TTS unit 110 receives the MPEG-2 TS input signal through the I / O unit (step S301). The PCR packet in the received MPEG-2 TS packet is searched (step S302), and the transmission rate of MPEG-2 TS is calculated from the number of TS packets arranged between the PCR packets in the found MPEG-2 TS ( In step S303), a process of adding a counter value to the head of each packet is performed (step S304). The above processing is repeated until the next MPEG-2 TS packet does not exist (step S305).

  FIG. 4 is a diagram showing an outline of ES replacement processing by the ES replacement unit 111 of the digital broadcast signal processing apparatus 100. As shown in the figure, the MPEG-2 TS packet includes a sequence header (SH) and a GOP (Group Of Pictures) composed of image frames. GOP is the minimum unit of data that can be cut out from MPEG-2 TS without decoding / recoding. Therefore, in the ES replacement process, when a replacement signal is generated, the signal is replaced in units of packets including a sequence header and a GOP unit.

Next, image frame cross-reference in the GOP will be described.
There are two types of GOPs: open GOPs and closed GOPs. In an open GOP, a video is reproduced while referring to adjacent image frames, whereas in a closed GOP, each GOP can reproduce a video without referring to another GOP.

FIG. 5 is a diagram schematically illustrating a method of referring to an image frame in the open GOP.
There are three types of image frames that constitute an open GOP: an I frame, a P frame, and a B frame. The I frame is a normal image frame, and it is not necessary to refer to another frame for reproduction. The P frame is an image frame in which a difference from the previous I frame or P frame is recorded, and it is necessary to refer to the previous I frame or P frame for reproduction. The B frame is an image frame in which a difference from the preceding and following I frames or P frames is recorded, and it is necessary to refer to the preceding and following (one or both) I frame, P frame, or B frame for reproduction.

In the frame group illustrated in the upper part of FIG. 5, the P04 frame refers to the previous P03 frame, the P05 frame refers to the previous I02 frame, the B09 frame refers to the previous P03 frame and the subsequent P04 frame, and the B10 frame is Refer to the previous P03 frame and the subsequent P04 frame, the B11 frame refers to the previous P04 frame and the subsequent I02 frame, the B12 frame refers to the previous P04 frame and the subsequent I02 frame, and the B13 frame refers to the previous P04 frame The I02 frame and the subsequent P05 frame are referred to, and the B14 frame refers to the previous I02 frame and the subsequent P05 frame.
As shown in the lower part of FIG. 5, in the signal output in MPEG-2, the GOP has a frame arrangement different from the actual reproduction order. This is due to the bidirectional reference characteristic of the B frame. For example, in the output signal sequence in the lower part of FIG. 5, the P04 frame is arranged before these for reproduction of the B9 and B10 frames. These frames can be rearranged with reference to time information such as PTS / DTS.

FIG. 6 is a diagram schematically showing an adjustment method in units of GOP image frames in the ES replacement process by the ES replacement unit 111 of the digital broadcast signal processing apparatus 100.
In FIG. 6, the case where the ES replacement process is performed between the first GOP and the second GOP will be described. Note that the input signal trains 1 and 2 in this example are the same signal trains as shown in FIG.
As shown in the upper part of FIG. 6, in the conventional ES replacement processing method, the B11 ′ frame and the B12 ′ frame in the second GOP immediately after replacement from the input signal sequence 1 to the input signal sequence 2 belong to the previous first GOP. Since decoding is performed with reference to the P04 frame, block noise, blackout, and the like occur.

  Therefore, in the present invention, in order to solve such a problem, the ES replacement unit 111 of the digital broadcast signal processing apparatus 100 refers to the image frame of the GOP before replacement in the GOP immediately after the replacement processing. That is, in the example of FIG. 6, the process of removing the B11 ′ frame and the B12 ′ frame from the output signal is performed. Thereby, it is possible to perform the replacement process smoothly without causing image distortion before and after the replacement process.

FIG. 7 is a flowchart showing in detail the flow of processing performed by the ES replacement unit 111 of the digital broadcast signal processing apparatus 100.
First, the ES replacement unit 111 of the digital broadcast signal processing apparatus 100 always receives the MPEG-2 TS packet input 1 and the input 2 from the TTS unit (step S701), and is included in these MPEG-2 TS packets. The sequence header to be searched is always searched (step S702). Here, when a replacement signal instructing replacement of ES is issued, replacement is performed from the immediately following sequence header and the subsequent GOP (step S703).

Subsequently, the ES replacement unit 111 searches for a B frame following the I frame in the GOP immediately after the replacement process (step S704), and the PTS value of the searched B frame is greater than the value of the reference image frame PTS. When it is smaller (ie, when referring to the forward direction) (step S705), a process of removing the B frame from the output signal is performed (step S706). On the other hand, if the retrieved B frame does not refer to the forward direction, it is output as it is (step S707).
When the next replacement signal is issued during the output of the MPEG-2 TS packet from the TTS unit, the processing from step S702 is repeated (step S708).
If there is no next replacement signal, the replaced data is output (step S709).

FIG. 8A is a diagram showing an overview of time information conversion processing by the time information conversion processing unit 112 of the digital broadcast signal processing apparatus 100.
As shown in FIG. 8A, time information such as PTS / DTS attached to the input signal 1 and the input signal 2 is not necessarily synchronized. When MPEG-2 TS packets with different time information added by ES replacement are mixed, the video / audio is disturbed by re-acquisition of time information on the receiver side to correct the disturbance. End up.
Therefore, in the digital broadcast signal processing apparatus 100, the time information conversion processing unit 112 performs a process of rewriting the time information of the other input signal so as to meet the standard of any one of the input signals (input signal 1 in the illustrated example). Do.

FIG. 8B is a flowchart showing in detail the flow of processing performed by the time information conversion processing unit 112.
In FIG. 8B, the time information conversion processing unit 112 receives the MPEG-2 TS packet from the ES replacement unit 111 (step S801), and searches for the PTS / DTS added to the PES header in the MPEG-2 TS packet ( In step S802), for the PTS / DTS of the input signal other than the reference input signal, the time information is rewritten so as to match the PTS / DTS of the reference input signal (step S803).
The above processing is repeated for each MPEG-2 TS packet (step S804).

FIG. 9A is a diagram showing an outline of TS arrangement processing by the TS arrangement unit 113 of the digital broadcast signal processing apparatus 100.
Based on the TTS counter value added to each MPEG-2TS packet by the TTS unit 110, the TS placement unit 113 determines the TTS interval of the packet (Pkt01, 03, 06) to be replaced, Packets to be replaced (Pkt01 is arranged in Pkt11, Pkt03 is arranged in Pkt14, and Pkt06 is arranged in Pkt18) are arranged at close points (Δt1≈Δt1 ′, Δt2≈Δt2 ′). This makes it possible to output packets at intervals very close to the input packet.

FIG. 9B is a flowchart showing in detail the flow of processing performed by the TS placement unit 113 of the digital broadcast signal processing apparatus 100.
9B, the TS arrangement unit 113 receives the MPEG-2 TS packet from the time information conversion processing unit 112 (step S901), and searches for the TTS counter value added to the MPEG-2 TS packet to be replaced ( In step S902), based on the input TTS interval, the packets are arranged at an interval close to the input packet (step S903).
The above processing is repeated for each MPEG-2 TS packet (step S904).
The MPEG-2 TS subjected to TS placement processing by the TS placement unit 113 is output as an output signal from the digital broadcast signal processing apparatus 100.

  The digital broadcast signal processing apparatus and the digital broadcast signal processing program of the present invention have been described with reference to specific embodiments, but the present invention is not limited to these. A person skilled in the art can make various changes and improvements to the configuration and function of each processing unit in each of the above embodiments without departing from the scope of the present invention.

  As shown in FIG. 1, the digital broadcast signal processing apparatus and the digital broadcast signal processing program of the present invention are realized by software built on hardware resources such as a computer CPU, memory, auxiliary storage device, and input / output device. Since the information processing that replaces multiple types of digital broadcast signals is realized by operating the above hardware resources as shown in FIGS. 2 to 9B, the natural law is used. This invention falls under the technical idea and can be used industrially.

It is a figure which shows schematically the internal structure of the digital broadcast signal processing apparatus concerning one Embodiment of this invention. It is a sequence diagram which shows the outline of the whole operation | movement of the digital broadcast signal processing apparatus shown in FIG. It is a figure which shows the outline | summary of the TTS conversion process by the TTS conversion part of the digital broadcast signal processing apparatus shown in FIG. It is a flowchart which shows in detail the flow of the process which the TTS part of the digital broadcast signal processing apparatus shown in FIG. 1 performs. It is a figure which shows the outline | summary of ES replacement | exchange process by ES replacement part of the digital broadcast signal processing apparatus shown in FIG. It is a figure which shows schematically the reference method of the image frame in open GOP. It is a figure which shows roughly the adjustment method of the GOP image frame unit in the ES replacement process by ES replacement part of the digital broadcast signal processing apparatus shown in FIG. It is a flowchart which shows in detail the flow of the process which ES replacement part of the digital broadcast signal processing apparatus shown in FIG. 1 performs. It is a figure which shows the outline | summary of the time information conversion process by the time information conversion process part of the digital broadcast signal processing apparatus shown in FIG. It is a flowchart which shows in detail the flow of the process which the time information conversion process part of the digital broadcast signal processing apparatus shown in FIG. 1 performs. It is a figure which shows the outline | summary of the TS arrangement | positioning process by TS arrangement | positioning part of the digital broadcast signal processing apparatus shown in FIG. It is a flowchart which shows in detail the flow of the process which TS arrangement | positioning part of the digital broadcast signal processing apparatus shown in FIG. 1 performs.

Explanation of symbols

100 Digital Broadcasting Signal Processing Device 110 TTS Unit 111 ES Replacement Unit 112 Time Information Conversion Processing Unit 113 TS Arrangement Unit

Claims (6)

A digital broadcast signal processing apparatus that partially replaces two or more input different encoded digital broadcast signal streams and outputs the digital broadcast signal stream as one stream,
When switching from one digital broadcast signal stream to another digital broadcast signal stream, an image frame included in the other digital broadcast signal stream and referring to the image frame at the stream position before replacement at the time of decoding A digital broadcast signal processing apparatus comprising stream replacement processing means for performing replacement processing by removing from an output signal.   For the one digital broadcast signal in the digital broadcast signal replaced by the stream replacement processing means, the time information added to the digital broadcast signal is the same format as the time information of the other digital broadcast signal. 2. The digital broadcast signal processing apparatus according to claim 1, further comprising time information conversion processing means for converting the time information into the time information. A time stamp addition processing unit for adding a time stamp to each input digital broadcast signal in units of packets;
A packet rearrangement processing unit that adjusts a temporal arrangement of each packet based on a time stamp added to each packet of the digital broadcast signal with respect to the digital broadcast signal subjected to the replacement process by the stream replacement processing unit; The digital broadcast signal processing apparatus according to claim 1 or 2, characterized by comprising: Receiving means for receiving two or more different encoded digital broadcast signal streams;
Stream replacement processing means for partially replacing the two or more digital broadcast signal streams to generate one stream of digital broadcast signals;
A digital broadcast signal processing program used in the digital broadcast signal processing apparatus, and an output means for outputting a digital broadcast signal of one stream generated by the stream replacement processing means,
When switching from one digital broadcast signal stream to another digital broadcast signal stream, an image frame included in the other digital broadcast signal stream and referring to the image frame at the stream position before replacement at the time of decoding A digital broadcast signal processing program for executing a stream replacement processing step for performing replacement processing by removing from an output signal. After executing the stream replacement process step,
Time information for converting the time information added to the digital broadcast signal into time information of the same format as the time information of the other digital broadcast signal with respect to the one digital broadcast signal in the replaced digital broadcast signal 5. The digital broadcast signal processing program according to claim 4, wherein the conversion processing step is executed. Before executing the stream replacement process step,
Execute a time stamp addition processing step of adding a time stamp to each input digital broadcast signal in units of packets;
After executing the stream replacement processing step or after executing the time information conversion processing step,
A packet rearrangement process is performed on the digital broadcast signal subjected to the replacement process, and the packet rearrangement process is performed to adjust a temporal arrangement of each packet based on a time stamp added to each packet of the digital broadcast signal. The digital broadcast signal processing program according to 4 or 5.

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