JP2008199516A - Data processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To record transport stream (TS) data in a size corresponding to a recording unit of a recording medium. <P>SOLUTION: A TS analysis circuit 14 counts an interval time T of a receiving TS packet and outputs the interval time T to an additional information adding circuit 16. The additional information adding circuit 16 adds 4-byte additional information to the receiving TS packet (188-byte length) according to the information T from the TS analysis circuit 14, and output to a TS packet complementing circuit 18. The TS packet complementing circuit 18 writes the TS packet with the additional information from the additional information adding circuit 16 into a memory 20. Further, after the TS data end, the TS packet complementing circuit 18 writes complementing TS packets according to the number of insufficient TS packets from the TS analysis circuit 14 into the memory 20. The TS packet with additional information and complementing TS packets in the memory 20 are recorded in a recording medium 30 by an instruction of a system control circuit 22. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a data processing apparatus for processing transport stream (TS) data.

  Conventionally, MPEG2 is known as a moving image data encoding method. In addition, MPEG2 program stream (MPEG2-PS) and MPEG2 transport stream (MPEG2-TS) are proposed as systems for multiplexing audio data and other additional data and transmitting them to moving picture data encoded in MPEG2. Has been.

  For example, in DVD video, image and audio data are recorded in the MPEG2-PS format. In digital terrestrial broadcasting, broadcast programs are transmitted in the MPEG2-TS format.

  MPEG2-TS is composed of 188-byte fixed-length packets called TS packets. As shown in FIG. 6, the TS packet includes a fixed-length header and an adaptation field or payload.

  In recent years, an apparatus for recording MPEG2-TS paved by terrestrial digital broadcasting directly on a recording medium such as a hard disk has appeared. In the case of recording MPEG2-TS, a method is also known in which each TS packet is recorded with a time stamp ATS (Arrival Time Stamp) as arrival time information added to the head (see, for example, Patent Document 1). .

  ATS is used for controlling transfer timing when reproducing recorded MPEG2-TS. The ATS added to each TS packet (188-byte length) mainly consists of 4 bytes because the added TS packet length is easier to handle when it is 192 bytes.

On the other hand, in a recording medium such as an optical disk, a hard disk device, or a semiconductor memory, recording / reproduction is often performed in units of a determined data amount. Therefore, even when MPEG2-TS is recorded on these recording media, it is necessary to record MPEG2-TS data according to the processing unit for each recording medium.
JP 09-135424 A

  When a 4-byte ATS is added to a TS packet, the recording processing unit for the recording medium and the end of the MPEG-TS may shift. If there is this deviation, the TS packet cannot be recorded on the recording medium as it is.

  In general, an apparatus that receives MPEG2-TS cannot determine the end of a TS packet.

  Therefore, conventionally, in order to match the end of the MPEG-TS with the processing unit delimiter of the recording medium, the transmitting device performs processing in advance so that the end of the TS packet matches the delimiter of the recording unit, I was sending.

  An object of the present invention is to solve such problems and to provide a data processing apparatus that appropriately adjusts the size of an MPEG-TS packet in a system that receives MPEG-TS packets.

  In order to achieve the above object, a data processing apparatus according to the present invention adds a TS receiving means for receiving transport stream (TS) data, and additional information to the TS data received by the TS receiving means. Additional information adding means for outputting attached TS data, and complementary means for complementing complementary TS data when the TS data with additional information is less than a processing unit.

  Preferably, the data processing apparatus according to the present invention further includes TS analysis means for analyzing the TS data received by the TS receiving means and extracting the additional information.

  Preferably, the additional information is time information.

  Preferably, the additional information is control information for recording / reproducing the TS data on a recording medium.

  According to the present invention, it is possible to add ATS or the like on the TS data receiving side without adding ATS or the like on the TS data transmitting side. Moreover, there is no need to be aware of the processing unit on the TS receiving side on the TS transmitting side. Furthermore, since there is a complementing means for complementing the data that is less than the processing unit, it is possible to finish recording TS data in a predetermined processing unit simply by registering the size information of the processing unit.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a schematic block diagram of a data processing apparatus according to an embodiment of the present invention. The data processing device 10 includes a TS receiving circuit 12, a TS analysis circuit 14, an additional information adding circuit 16, a TS packet complementing circuit 18, and a memory 20.

  The TS receiving circuit 12 receives a TS packet (188-byte length) input from the outside of the data processing apparatus 10 and outputs it to the TS analysis circuit 14 and the additional information adding circuit 16. The TS analysis circuit 14 counts the TS packet interval time T and outputs the interval time T to the additional information adding circuit 16.

  The additional information adding circuit 16 adds 4 bytes of additional information to the TS packet (188 bytes long) from the TS receiving circuit 12 in accordance with the TS packet interval time information T from the TS analyzing circuit 14, and a 192 byte long TS packet. Is output to the TS packet complement circuit 18. Hereinafter, the TS packet with additional information added is referred to as a TS packet with additional information.

  Further, the TS analysis circuit 14 detects the end of the TS data, and calculates the number of TS packets that are insufficient in units of TS packets with additional information (192-byte length) with respect to the recording processing unit (for example, 6144 bytes) of the recording medium 30. Calculate. The TS analysis circuit 14 outputs the number of insufficient TS packets to the TS packet complement circuit 18 in accordance with the end of the TS data. For the end of TS data, the reception interval of TS packets (188 bytes long) is monitored by a watchdog timer or the like, or PAT (Program Association Table), PMT (Program Map Table) in TS packets (188 bytes long) Can be detected by monitoring the interval with a watchdog timer or the like.

  The TS packet complementing circuit 18 writes the TS packet with additional information (192-byte length) from the additional information adding circuit 16 into the memory 20. Further, after completion of the TS data, the TS packet complementing circuit 18 writes a complementary TS packet having a length of 192 bytes corresponding to the number of insufficient TS packets from the TS analyzing circuit 14 to the memory 20. The complementary TS packet (192 byte length) is composed of 4-byte additional information generated by the additional information adding circuit 16 and a TS packet (188 byte length) that does not make sense such as a TS null packet having a PID of 0x1FFF. This is also a TS packet with additional information. The TS packet with additional information (192-byte length) written in the memory 20 is recorded on the recording medium 30 in accordance with an instruction from the system control circuit 22 composed of an MPU or the like.

  The format of a TS packet with additional information (192-byte length) will be described with reference to FIGS. FIG. 2 is a schematic diagram of the structure of a TS packet with additional information (192-byte length) when the 4-byte additional information is composed of ATS. As shown in FIG. 2, 4-byte ATS is added to the MSB (Most Significant Bit) side of the TS packet (188 bytes long). ATS indicates the arrival time of the first bit of the first byte of the TS packet (188-byte length).

  FIG. 3 is a schematic diagram of the structure of a TS packet with additional information when 30 bits of 4-byte additional information are assigned to ATS and the remaining 2 bits are assigned to control information (for example, a frame identification flag or a copy control flag). Show. When the frame identification flag is used as the control information, for example, the TS analysis circuit 14 identifies I, B, and P picture types from the PCT (Picture Coding Type) of the input TS data, and indicates the identification result. The information is output to the additional information adding circuit 16. In the case of the copy control flag, the additional information adding circuit 16 adds the copy control flag in accordance with an instruction from the system control circuit 22 or the like.

  A method for generating an ATS will be described with reference to FIG. In FIG. 4, N1 to N4 indicate TS packets (188-byte length) input from the outside. M1 to M4 indicate TS packets with additional information (192-byte length). T1 to T3 indicate values obtained by counting the arrival interval of the first bit of the first byte of the TS packet (188-byte length) input from the outside with a clock signal (27 MHz). S1 to S4 indicate 4-byte additional information.

  Hereinafter, a case where 4-byte additional information (S1 to S4) is used only in ATS will be described. The initial value of S1 is set by the system control circuit 22 or the like. In S2, a value obtained by adding S1 to a value T1 obtained by counting the arrival interval of the first bit of the first byte of N1 and N2 with a clock signal (27 MHz) is set. That is, S2 = S1 + T1. Hereinafter, S3 = S2 + T2, S4 = S3 + T3, and so on. With respect to the additional information 4 bytes of the complementary TS packet complemented by the TS packet complementing circuit 18, T cannot be generated because the input TS data has already been completed. In this case, the previous value of T is used, or the average value of T up to the previous time is used.

  When the 2-bit frame identification flag is included in the additional information, information from the TS analysis circuit 14 is set in the upper 2 bits of S, and the ATS described above is assigned to the remaining 30 bits. The same applies when the copy control flag 2 bits are used for the additional information.

  As described above, according to the present embodiment, TS data can be recorded with a size suitable for the recording medium by simple processing regardless of the data amount of the input TS data.

  When the clock signal is not synchronized between the TS output device and the TS input device, a means for clock synchronization, for example, a PLL circuit may be added as appropriate. FIG. 5 shows a schematic block diagram of the modified embodiment. In the data processing device 10a shown in FIG. 5, a PLL circuit 24 is connected to the TS analysis circuit 14a. The operations of the other elements are the same as those in the first embodiment, and are denoted by the same reference numerals.

  The TS analysis circuit 14 a extracts a PCR (Program Clock Reference) included in the TS data and outputs the extracted PCR to the PLL circuit 24. The PLL circuit 24 takes a difference value between the output value of the counter operating with the clock signal (27 MHz) generated from the voltage controlled oscillator (VCO) and the PCR value input from the TS analysis circuit 14a. The PLL circuit 24 controls the oscillation frequency of the voltage controlled oscillator so that the difference value becomes zero. The TS analysis circuit 14 a counts the interval time of the TS packet (188 bytes long) using the clock signal output from the PLL circuit 24, and outputs the interval time information T to the additional information adding circuit 16.

  In this embodiment, even when the data processing device 10a operates in a clock domain different from that of the TS output device (not shown), that is, when the data processing device 10a operates asynchronously with the TS output device, the additional information adding circuit 16 adds 4 bytes. Information can be stably added to a TS packet. As a result, the TS data can be recorded with a size suitable for the recording medium by simple processing regardless of the amount of input TS data.

It is a schematic block diagram of Example 1 of the present invention. It is a schematic diagram of the structural example of TS packet with additional information. It is a schematic diagram of another structural example of TS packet with additional information. It is explanatory drawing of ATS. It is a schematic block diagram of the second embodiment of the present invention. It is a schematic diagram which shows the structure outline of TS packet.

Explanation of symbols

10, 10a Data processing device 12 TS receiving circuit 14, 14a TS analyzing circuit 16 Additional information adding circuit 18 TS packet complementing circuit 20 Memory 22 System control circuit 24 PLL circuit 30 Recording medium

Claims (4)

TS receiving means (12) for receiving transport stream (TS) data;
Additional information adding means (16) for adding additional information to the TS data received by the TS receiving means and outputting TS data with additional information;
Complementing means for complementing supplementary TS data when the TS data with additional information is less than the processing unit (18)
A data processing apparatus comprising:   The data processing apparatus according to claim 1, further comprising TS analysis means (14) for analyzing TS data received by the TS reception means and extracting the additional information.   The data processing apparatus according to claim 1, wherein the additional information is time information.   4. The data processing apparatus according to claim 1, wherein the additional information is control information for recording / reproducing the TS data on a recording medium.

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