JP4551890B2 - Receiver - Google Patents

Description

  The present invention relates to an input / output device, an input / output method, and a receiving device, and particularly suitable for use in, for example, an IRD (Integrated Receiver and Decoder) or STB (Set Top Box) that receives digital broadcast data. And an input / output method and a receiving apparatus.

  Digital satellite broadcasting has begun in earnest due to an increase in the number of satellites, progress in the development of facilities for digital satellite broadcasting, and other reasons.

  In digital satellite broadcasting, digital data as a program is generally scrambled in order to charge for viewing the program and prevent interception by a person who does not have a reception contract for the program. On the other hand, in the IRD possessed by a legitimate contractor, the scrambled digital data is descrambled, so that the legitimate contractor can view the program. In addition, when descrambling is performed, information required for charging may be accumulated in the IRD.

  For example, when digital video data or digital audio data as a program is MPEG (Moving Picture Experts Group) encoded and transmitted as an MPEG transport stream (hereinafter referred to as TS as appropriate), IRD From the descrambling data obtained by descrambling, a transport packet (hereinafter referred to as TS packet) of a desired channel (program) is extracted and MPEG-decoded. Provided to.

  Conventionally, in the IRD, in addition to the data obtained as a result of MPEG decoding as described above, basically only TS obtained by descrambling digital data is output to the outside. .

  However, it is convenient if data before descrambling can be output to the outside from the IRD, or data before or after descrambling can be input to the IRD from an external device.

  In other words, for example, there are cases where descrambling and billing processing is desired to be performed by an external device instead of the IRD. However, for this purpose, it is necessary to output digital data before descrambling from the IRD to an external device. Further, when the external device does not have a decoder that performs MPEG decoding, in order to perform MPEG decoding, it is necessary to input the data descrambled by the external device to the IRD.

  The present invention has been made in view of such a situation, and makes it possible to input / output data flexibly to a receiving apparatus that receives digital data such as IRD.

A receiving apparatus according to an aspect of the present invention includes a receiving unit that receives a scrambled transport stream, a descrambling process that is performed on the scrambled transport stream supplied from the receiving unit. Descrambling means for generating a transport stream, interface means, input / output control means for controlling input / output between the receiving means or the descrambling means and the interface means, and transport from the interface means and a recording and reproducing means for recording and reproducing the stream packets, the descrambling means, said recording and reproducing means transport stream reproduced by the, whether is scrambled, of the transport stream DOO Has a determination means for determining by referring to the scramble control bits contained in Nsu transport stream packet further transport in the determination unit, the transport stream reproduced by said reproducing means is scrambled If it is determined that the stream is a stream, a descrambling process is performed on the transport stream reproduced by the recording / reproducing unit. In the determining unit, the transport stream reproduced by the recording / reproducing unit is already When it is determined that the transport stream is descrambled, the transport stream reproduced by the recording / reproducing means is output without executing the descrambling process, and the input / output control means Output by the receiving means A first selection means for selecting one of a transport stream or a transport stream supplied from the interface means and supplying the selected transport stream to the descrambling means; a selection output of the first selection means; Second selection means for selecting one of the transport streams output from the scramble means, and detects the PID of the transport stream output from the second selection means, and is designated by the user Compared with the PID of the transport stream packet of the program, the transport stream packet is selectively output and supplied to the interface means when they match .

In one aspect of the present invention, the scramble control bit included in the transport stream packet of the transport stream is referred to as to whether or not the transport stream reproduced by the recording / reproducing means is scrambled. If it is determined that the reproduced transport stream is a scrambled transport stream, a descrambling process is performed on the reproduced transport stream, and the reproduced transport stream is If it is determined that the transport stream has already been descrambled, the transport stream that has been reproduced is output without being descrambled. In the input / output control means for controlling the input / output between the receiving means or the descrambling means and the interface means, the PID of the transport stream output from the second selection means is detected, and the program specified by the user is transcoded. When compared with the PID of the port stream packet, if it matches, the transport stream packet is selectively output and supplied to the interface means.

  According to the present invention, flexible input / output of digital data can be performed.

  FIG. 1 shows an embodiment of a broadcasting system to which the present invention is applied (a system is a logical collection of a plurality of devices, regardless of whether or not each component device is in the same housing). The example of a structure of the form is shown.

  On the broadcasting station side, for example, digital video data and digital audio data as programs are MPEG-encoded in the transmission device 1, and the digital data is scrambled. Further, in the transmission apparatus 1, a TS in which digital data as a program and other necessary data are arranged is configured, and after necessary processing such as error correction is performed, for example, QPSK (Quadrature Phase Shift Keying) modulation is performed. The In the transmission device 1, the resulting modulated signal is up-converted and transmitted as a radio wave from the antenna (parabolic antenna) 2. In the transmission apparatus 1, for example, a TS in which data for six programs is multiplexed is configured for one transponder.

  The radio wave from the antenna 2 is received by the satellite 3 and transmitted after being subjected to amplification and other necessary processing in a transponder (not shown). Radio waves from the satellite 3 are received by the antenna (parabolic antenna) 4 on the user (viewer) side, down-converted, and then supplied to the IRD 5 (receiving device).

  In the IRD 5, first, a signal from the antenna 4 is selected. That is, the satellite 3 generally has a plurality of transponders, and the antenna 4 receives radio waves transmitted from the plurality of transponders and down-converts them. Therefore, since the signals supplied from the antenna 4 include signals from the plurality of transponders, in the IRD 5, the signal corresponding to any one of the transponders is selected from the signals corresponding to the plurality of transponders. Is selected in accordance with the channel selection operation performed by.

  Further, in the IRD 5, a selected signal, that is, a QPSK-modulated signal is QPSK demodulated, and the resulting TS is subjected to error correction and other necessary processing. Then, the TS after error correction is descrambled, and the TS packet of the channel selected by the user is extracted from the descrambled TS. Then, the data arranged in the TS packet is subjected to MPEG decoding, and the resulting image is supplied to the monitor 6 and displayed (sound is output from a speaker not shown).

  The IRD 5 is connected to a DVCR (Digital Video Cassette Recorder) 7 as an external device in accordance with, for example, the standard of IEEE (Institute of Electrical and Electronics Engineers) 1394, which is a serial interface standard. Then, the descrambled TS or the descrambled TS can be exchanged with the DVCR 7. For example, when the descrambled TS is received from the DVCR 7, the IRD 5 performs MPEG decoding on the TS and outputs it to the monitor 6. When the TS before descrambling is received, the IRD 5 Is descrambled and further MPEG-decoded and output to the monitor 6.

  The DVCR 7 records the data from the IRD 5, reproduces the recorded data, and supplies it to the IRD 5.

  In the IRD 5, when descrambling is performed, processing related to charging for viewing the program, that is, processing for creating a viewing history, for example, is performed as necessary. The billing information obtained as a result of the processing is transmitted to the transmission device 1 via, for example, the public network 8, and the transmission device 1 performs billing based on this billing information.

  Next, FIG. 2 shows a configuration example of the IRD 5 of FIG.

  As shown in the figure, the IRD 5 is roughly composed of a reception processing unit 10 and a data interface 20. The reception processing unit 10 includes a front end unit 11 (reception means), a descrambler 12 (descrambler). Means), a decoding unit 13, a controller 14, and a modem 15, and the data interface 20 is constituted by a switching unit 21 (input / output control unit) and an IEEE 1394 interface 22 (interface unit). The blocks constituting the reception processing unit 10 and the data interface 20 are connected to each other via the control bus 16.

  The front end unit 11 receives a reception signal received by the antenna 4 and down-converted, performs predetermined reception processing on the reception signal, and obtains a TS (before descrambling). ) To the input terminal IN1 of the switching unit 21. The descrambler 12 descrambles the TS (before descrambling) supplied from the output terminal OUT of the switching unit 21, and the descrambled TS is input to the input terminal IN2 of the decoding unit 13 and the switching unit 21. It is made to supply to.

  The decoding unit 13 extracts the one corresponding to the channel selected by the user from the TS packets constituting the descrambled TS supplied from the descrambler 12 and MPEG-decodes it. Then, the resulting image and sound are output. Further, the decoding unit 13 extracts from the descrambled TS supplied from the descrambler 12 what control data necessary for control is arranged, and sends the control data to the controller via the control bus 16. 14 is also output.

  The controller 14 is supplied from control data supplied from the decoding unit 13, a signal supplied when a user operates a remote controller (remote commander) (not shown), and a block connected to the control bus 16. The front-end unit 11, the descrambler 12, the decoding unit 13, the controller 14, the modem 15, the switching unit 21, and the IEEE 1394 interface 22 constituting the IRD 5 are performed via the control bus 16. Has been made to control.

  For example, the modem 15 performs communication control for transmitting billing information and the like to the transmission device 1 via the public network 8.

  Under the control of the controller 14, the switching unit 21 supplies the output of the front end unit 11 supplied to the input terminal IN 1 as it is to the descrambler 12 from the output terminal OUT, and the front end unit 11 outputs the output. The descrambled TS output from the descrambler 12 or the descrambled TS output from the descrambler 12 is supplied from the input / output terminal IN / OUT to the DVCR 7, which is an external device, via the IEEE 1394 interface 22. The data supplied to the input / output terminal IN / OUT via the IEEE1394 interface 22 is supplied to the descrambler 12 from the output terminal OUT.

  The IEEE 1394 interface 22 communicates with the DVCR 7 in conformity with the IEEE 1394 standard, thereby transmitting data supplied from the input / output terminal IN / OUT of the switching unit 21 to the DVCR 7 and from the DVCR 7. The received data is received and supplied to the input / output terminal IN / OUT of the switching unit 21. In the embodiment of FIG. 2, the IEEE 1394 interface 22 has three input / output ports to the outside, but the number of input / output ports is not particularly limited.

  Here, in the conventional IRD, the data interface 20 is not provided, and the output of the front end unit 11 is directly supplied to the descrambler 12. Therefore, the IRD 5 is greatly different from the conventional case in that the data interface 20 is provided and the output of the front end unit 11 is supplied to the descrambler 12 via the switching unit 21. Different.

  Next, the operation will be described.

  First, when viewing a program in real time (the operation mode of the IRD 5 in this case is hereinafter referred to as a normal mode as appropriate), the channel of the program is selected by the user. In this case, the controller 14 recognizes the transponder used for broadcasting of the channel and controls the front end unit 11 via the control bus 16 so as to select a reception signal from the transponder. The front end unit 11 receives a reception signal from the antenna 4 and selects a reception signal in a frequency band corresponding to the control from the controller 14. Further, in the front end unit 11, the received signal is subjected to predetermined processing to be converted to TS and supplied to the input terminal IN 1 of the switching unit 21.

  In this case, the controller 14 controls the switching unit 21 via the control bus 16 so that a signal input to the input terminal IN1 is output from the output terminal OUT. In accordance with this control, the switching unit 21 outputs the TS from the front end unit 11 input to IN1 as it is from the output terminal OUT. The TS output from the output terminal OUT is supplied to the descrambler 12.

  In the descrambler 12, the scrambled TS supplied from the switching unit 21 is descrambled, and the descrambled TS is supplied to the decoding unit 13.

  At this time, the controller 14 controls the decoding unit 13 via the control bus 16 so as to decode the packet of the channel selected by the user. The decoding unit 13 follows the control from the descrambler 12. From the supplied TS packets constituting the descrambled TS, those corresponding to the channel selected by the user are extracted and MPEG-decoded. As a result, the image of the program broadcast on the channel selected by the user is displayed and the corresponding sound is output.

  Next, in the case where the TS before descrambling is output to the DVCR 7 (the operation mode of the IRD 5 in this case is hereinafter referred to as a non-descrambling output mode as appropriate), the controller 14 outputs the front end unit 11. The switching unit 21 is controlled via the control bus 16 so as to output TS to the IEEE 1394 interface 22.

  In accordance with this control, the switching unit 21 outputs the TS supplied from the front end unit 11 to the input terminal IN1 to the IEEE 134 interface 22 from the input / output terminal IN / OUT.

  At this time, the controller 14 controls the IEEE 1394 interface 22 via the control bus 16 so as to output the data from the switching unit 21 to the DVCR 7, and the IEEE 1394 interface 22 follows this control. The TS before descrambling supplied from the terminal 21 is transmitted to the DVCR 7 by a communication procedure compliant with the IEEE 1394 standard.

  In this case, the controller 14 sends an AV / C (Audio Visual / Control) command (hereinafter referred to as a recording AV / C command as appropriate) for instructing recording via the control bus 16 and the IEEE 1394 interface 22. Send to DVCR7. The DVCR 7 records the TS before descrambling supplied from the IEEE 1394 interface 22 in accordance with the recording AV / C command. Here, the DVCR 7 has an interface having the same function as the IEEE 1394 interface 22, and communication conforming to the IEEE 1394 standard is performed between the interface and the IEEE 1394 interface 22, whereby the IRD 5 and the DVCR 7 Data and commands are exchanged between them.

  Next, in the case of outputting the descrambled TS to the DVCR 7 (in this case, the operation mode of the IRD 5 is hereinafter referred to as a descrambling output mode as appropriate), the controller 14 receives a signal input to the input terminal IN1. Is output from the output terminal OUT and the switching unit 21 is controlled via the control bus 16 so that a signal input to the input terminal IN2 is output from the input / output terminal IN / OUT.

  In accordance with this control, the switching unit 21 first outputs the TS from the front end unit 11 input to the IN1 as it is from the output terminal OUT. The TS output from the output terminal OUT is supplied to the descrambler 12 and descrambled. The descrambled TS is supplied to the input terminal IN2 of the switching unit 21. The switching unit 21 outputs the TS from the descrambler 12 supplied to the input terminal IN2 to the IEEE 134 interface 22 from the input / output terminal IN / OUT.

  Thereafter, the descrambled TS from the switching unit 21 is transmitted to the DVCR 7 and recorded in the IEEE 1394 interface 22 in the same manner as in the non-descramble output mode.

  Next, when the data recorded in the DVCR 7 is reproduced and input to the IRD 5 (the operation mode of the IRD 5 in this case is hereinafter referred to as input mode as appropriate), the controller 14 instructs to perform the reproduction. An AV / C command to be performed (hereinafter referred to as a playback AV / C command as appropriate) is transmitted to the DVCR 7 via the control bus 16 and the IEEE 1394 interface 22. In the DVCR 7, in accordance with this playback AV / C command, the data recorded there is played back.

  At this time, the controller 14 controls the IEEE 1394 interface 22 via the control bus 16 so that the data output from the DVCR 7 is supplied to the switching unit 21, and the IEEE 1394 interface 22 follows this control. The data (here, TS) reproduced in the DVCR 7 is received by a communication procedure compliant with the IEEE 1394 standard. Then, the IEEE 1394 interface 22 supplies the TS received from the DVCR 7 to the input / output terminal IN / OUT of the switching unit 21.

  The switching unit 21 outputs the TS supplied to the input / output terminal IN / OUT from the output terminal OUT. The TS output from the output terminal OUT is supplied to the descrambler 12.

  When the TS supplied from the switching unit 21 is scrambled, the descrambler 12 performs descrambling and supplies it to the decoding unit 13. Further, when the TS supplied from the switching unit 21 is not scrambled, the descrambler 12 supplies it to the decoding unit 13 as it is. Thereafter, in the same way as in the normal mode, the decoding unit 13 performs MPEG decoding of the TS output from the descrambler 12.

  In the descrambler 12, whether the TS (TS packet) is scrambled can be recognized by referring to 2 bits for scramble control of the TS packet shown in FIG. 5 described later. Has been made.

  Next, FIG. 3 shows a configuration example of the front end portion 11 of FIG.

  A reception signal from the antenna 4 is supplied to the tuner 31. The tuner 31 receives a reception signal from the antenna 4 and selects a reception signal in a frequency band corresponding to a predetermined transponder according to a control signal supplied from the controller 14 via the control bus 16. The selected received signal is supplied to the demodulation circuit 32. In the demodulation circuit 32, the received signal from the tuner 31 is converted to TS, for example, as QPSK demodulated, and supplied to the error correction circuit 33. In the error correction circuit 33, error correction processing is performed on the TS from the demodulation circuit 32 and supplied to the input terminal IN 1 of the switching unit 21.

  Next, FIG. 4 shows a configuration example of the decoding unit 13 of FIG.

  The descrambled TS (unscrambled TS) supplied from the descrambler 12 is supplied to a DMUX (demultiplexer) 41. In DMUX 41, necessary TS packets are extracted by referring to PID (Packet Identification) included in each TS packet constituting the TS, and supplied to corresponding ones of RAM (Random Access Memory) 42 to 45. The

  That is, the DMUX 41 extracts a TS packet in which information (for example, PCR (Presentation Clock Reference)) for generating a clock necessary for processing is arranged, and supplies the extracted TS packet to the RAM 42. In addition, the DMUX 41 extracts TS packets in which video data or audio data (in this case, MPEG encoded data) of the channel selected by the user is arranged, and supplies the TS packets to the RAM 43 or 44, respectively. Further, the DMUX 41 extracts a TS packet in which information for performing various controls is arranged and supplies the extracted TS packet to the RAM 45.

  Of the TS packets constituting the TS, those not selected in the DMUX 41 are discarded.

  In the RAMs 42 to 45, TS packets supplied from the DMUX 41 are stored.

  Then, in the clock generator 46, the TS packet stored in the RAM 42 is read, and a clock is generated based on the information arranged there. This clock is supplied to the MPEG video decoder 47, the MPEG audio decoder 48, and other necessary blocks.

  In the MPEG video decoder 47 or the MPEG audio decoder 48, the TS packet stored in the RAM 43 or 44 is read out, and the MPEG-encoded video data or audio data arranged therein is MPEG-decoded and output. .

  In the microcomputer (microcomputer) 49, the TS packet stored in the RAM 45 is read, and control data for controlling each block is extracted based on the information arranged there. This control data is supplied to the necessary blocks via the control bus 16.

  Here, FIG. 5 shows the data structure of the TS.

  The TS is composed of 188-byte TS packets as shown in FIG.

  The 4 bytes (32 bits) from the head of each TS packet are a so-called packet header, and the remaining 184 bytes are both the adaptation field and the payload, or only the payload.

  The information placed in the packet header is defined in the MPEG2 standard. For example, the latest MPEG textbook, supervised by Hiroshi Fujiwara, edited by Multimedia Communications Research Group, published by ASCII Publishing Bureau, etc. Since details are disclosed, a detailed description is omitted here. However, if necessary are briefly described here, the PID arranged in the 13th bit from the 12th bit to the 24th bit is the TS Used for packet identification. The 2-bit scramble control arranged after the PID represents the presence / absence and type of payload scramble. As described above, the descrambler 12 recognizes whether or not the TS packet (payload) is scrambled by referring to the scramble control.

  Here, only one PCR used as information for generating a clock used in the above-described clock generator 46 may be arranged in the adaptation field, or a plurality of PCRs may be arranged together in the payload. Any method is allowed in the MPEG2 standard.

  Next, as described above, in DMUX 41 (FIG. 4), necessary TS packets are extracted by referring to the PID included in the TS packets. Regarding the extraction method, video data of a desired channel is arranged. An example in which extracted TS packets are extracted will be described.

  A TS packet in which video data of a certain channel is arranged is assigned a unique PID corresponding to that channel. Therefore, in order to extract a TS packet of a desired channel, the value of PID attached to the packet of that channel is required. Therefore, a TS packet describing an additional information table (PSI) (Program Specific Information), which is information for recognizing the correspondence between channels and PIDs, is included in the TS.

  Here, PSI includes, for example, PAT (Program Association Table) and PMT (Program Map Table).

  A predetermined fixed value (0x00 (0x represents that the following number is a hexadecimal number) is assigned in advance to the PAT as a PID. As shown in FIG. A PID of a PMT to be referred to in order to obtain a TS packet of “Program No.” (corresponding to a channel) is described.

  As shown in FIG. 6B, the PMT describes the PID of a TS packet (video packet) as shown in FIG. 6C in which video data of a program corresponding to a certain program number is arranged. Yes.

  Therefore, in order to extract a TS packet in which video data of a desired channel is arranged, first, a packet with a PID of 0x00, that is, a PAT is received (FIG. 6A), and a program number corresponding to the desired channel is obtained. The associated PID is detected. Then, the TS packet to which the PID is added, that is, the PMT is received (FIG. 6B). Further, the PID described in the PMT is detected, and the video packet to which the PID is added is received (FIG. 6C).

  Specifically, for example, in the case of extracting a TS packet in which video data of a channel corresponding to the program number “1” is extracted, the PID of the PMT for the program number is determined by the PAT (FIG. 6A). Is recognized as “11”. Then, by receiving the TS packet of the PMT (FIG. 6B), it is recognized that the PID of the TS packet in which the video data of the channel corresponding to the program number “1” is arranged is “p”. The Then, a TS video packet (FIG. 6C) with a PID of “p” is extracted.

  Note that the header of the TS packet shown in FIG. 5 is deleted in the DMUX 41 and the rest is supplied to the RAMs 42 to 45 (thus, in the description of FIG. 4, the TS packet is supplied to the RAMs 42 to 45. Exactly, the portion excluding the header of the TS packet is supplied to the RAMs 42 to 45).

  Next, FIG. 7 shows a configuration example of the controller 14 of FIG.

  An I / F (Interface) 51 connects the control bus 15 and the internal bus 55, and outputs a signal supplied via the control bus 16 to a CPU (Central Processor Unit) 52 via the internal bus 55. At the same time, the control data supplied from the CPU 52 via the internal bus 55 is output to a necessary block via the control bus 16.

  The CPU 52 performs various processes based on signals supplied from the I / F 51 via the internal bus 55, generates control data, and supplies the control data to the I / F 51. The I / F 51 also supplies a signal corresponding to the operation of the user's remote control to the CPU 52, and the CPU 52 performs various processes in response to the signal.

  A ROM (Read Only Memory) 53 stores an IPL (Initial Program Loading) program and other programs and data required for startup. The CPU 52 becomes operable by reading the program and data stored in the ROM 53 through the internal bus 55 when the IRD 5 is turned on or reset.

  The RAM 54 stores programs (OS (Operating System), application programs, etc.) and data necessary for the operation of the CPU 52. The RAM 54 is composed of, for example, a flash memory.

  Next, FIG. 8 shows a configuration example of the switching unit 21 of FIG.

  As shown in the figure, the switching unit 21 is roughly composed of a switcher 60 and a data parser unit 70 (extraction means).

  The switcher 60 is composed of switches 61 to 63.

  The terminal 61a of the switch 61 (first selection means) is connected to the input terminal IN1, and therefore, the TS before descrambling is supplied from the front end unit 11 thereto. The terminal 61b of the switch 61 is connected to the terminal 63b of the switch 63. The switch 61 is connected to the terminal 62b and the output terminal OUT of the switch 62 (second selection means), and selects either the terminal 61a or 61b according to control from the controller 14. ing.

  The terminal 62a of the switch 62 is connected to the input terminal IN2. Therefore, the descrambled TS is supplied from the descrambler 12 to the terminal 62a. The switch 62 is connected to the PID detection unit 71 of the data parser unit 70, and selects either one of the terminals 62a or 62b in accordance with the control from the controller 14, or selects neither of them. It is made to become.

  The switch 63 is connected to the input / output terminal IN / OUT, and selects either one of the terminals 63a and 63b in accordance with control from the controller 14. The output of the parser 74 of the data parser unit 70 is supplied to the terminal 63a.

  The data parser unit 70 includes a PID detection unit 71, a comparison unit 72, a register unit 73, and a parser 74. The data parser unit 70 extracts only necessary TS packets from the TS supplied from the switch 62 and supplies the extracted TS packets to the terminal 63a. Has been made.

  That is, the PID detector 71 outputs the TS supplied from the switch 62 to the parser 74 as it is, detects the PID from each TS packet constituting the TS, and supplies it to the comparator 72. . The comparison unit 72 compares the PID stored in the register unit 73 with the PID from the PID detection unit 71, and if the two match, the comparison unit 72 sends a signal to that effect (hereinafter referred to as a match signal as appropriate) to the parser. 74 is provided. The register unit 73 stores the PID supplied from the controller 14 via the control bus 16. That is, for example, there is a case where the user wants the DVCR 7 to record only a program of a certain channel. In such a case, when the user designates that channel, the controller 14 causes the TS packet corresponding to that channel to be recorded. Are supplied to the register unit 73 via the control bus 16. The register unit 73 stores the PID supplied from the controller 14 in this way. The register unit 73 can store a plurality of PIDs.

  The parser 74 receives a TS packet corresponding to the coincidence signal supplied from the comparison unit 72 from the TS supplied from the PID detection unit 71, that is, a TS packet having the same PID as the PID stored in the register unit 73. Extracted and supplied to the terminal 63a. Note that TS packets not extracted by the parser 74 are discarded.

  Next, the operation of the switching unit 21 in each of the above-described normal mode, descrambling output mode, non-descrambling output mode, or input mode will be described. It is assumed that a predetermined PID is set in the register unit 73 by the controller 14.

  In each mode, the controller 14 controls the switches 61 to 63 so as to select terminals as shown in FIG.

  That is, in this case, in the normal mode, the switch 61 selects the terminal 61a, and the switch 62 enters a state in which neither of the terminals 62a and 62b is selected (hereinafter referred to as a free state as appropriate). Further, the switch 63 is in a don't care state (a state in which either the terminal 63a or 63b may be selected). Therefore, the TS before descrambling supplied from the front end unit 11 to the terminal 61a via the input terminal IN1 is output as it is from the output terminal OUT via the switch 61 and supplied to the descrambler 12.

  Next, in the descrambling output mode, as shown in FIG. 9, the switch 61 selects the terminal 61a, the switch 62 selects the terminal 62a, and the switch 63 selects the terminal 63a.

  Accordingly, in this case as well, as in the normal mode, the undescrambled TS supplied from the front end unit 11 to the terminal 61a via the input terminal IN1 passes through the switch 61 and is directly output from the output terminal OUT. It is output and supplied to the descrambler 12.

  In the descrambler 12, the descrambled TS from the output terminal OUT is descrambled, and the descrambled TS is supplied to the terminal 62a via the input terminal IN2. Since the switch 62 selects the terminal 62 a, the descrambled TS supplied to the terminal 62 a is supplied to the PID detection unit 71 via the switch 62.

  The PID detection unit 71 outputs the TS supplied from the switch 62 to the parser 74 as it is, detects the PID from each TS packet constituting the TS, and supplies it to the comparison unit 72. In the comparison unit 72, the PID stored in the register unit 73 is compared with the PID from the PID detection unit 71, and a match signal is supplied to the parser 74 only when they match.

  When the parser 74 receives a match signal from the comparison unit 72, the TS packet corresponding to the match signal (a TS packet having the same PID as the PID stored in the register unit 73) (hereinafter, referred to as a match packet as appropriate). And the other TS packets are deleted and output to the terminal 63a.

  Here, the parser 74 holds a relative time interval between matching packets (a state where a time interval from one matching packet to the next matching packet is maintained) when outputting the matching packet to the terminal 63a. The matching packet is output to the terminal 63a. This is because MPEG decoding becomes difficult if the relative time interval between matching packets is lost.

  The switch 63 selects the terminal 63a. Therefore, the coincidence packet output from the parser 74 is output from the input / output terminal IN / OUT via the switch 63 and supplied to the IEEE 1394 interface 22. In the IEEE 1394 interface 22, the matching packet (here, the descrambled TS packet) from the switching unit 21 is formatted in conformity with the IEEE 1394 standard and transmitted to the DVCR 7.

  At this time, as described above, the controller 14 transmits a recording AV / C command to the DVCR 7 via the IEEE 1934 interface 22. Therefore, in the DVCR 7, data supplied from the IEEE 1934 interface unit 22 is recorded. The

  Here, the matching packet sequence that is the output of the parser 74 is an interval in which the TS other than the matching packet is missing from the original TS, so that such a missing tooth TS is replaced with another device. Needs to be processed so that it can be processed normally when received. As this processing, for example, addition of PAT, PMT, SIT (Selection Information Table), DIT (Discontinuity Information Table) related to the matching packet can be cited. Therefore, the controller 14 generates these PAT, PMT, SIT, and DIT and supplies them to the IEEE1394 interface 22 via the control bus 16. The IEEE 1394 interface 22 inserts the PAT, PMT, SIT, and DIT from the controller 14 in the form of TS packets into a portion where the tooth gap TS is open, and thereby a partial transport stream (Partial Transport Stream). Stream) (hereinafter referred to as “partial TS” where appropriate), and transmits this to the DVCR 7.

  Details of PAT, PMT, SIT, DIT, etc. are described in, for example, ETS 300468, Digital Video Broadcasting (DVB); Specification for Service Information (SI) in DVB system.

  Next, in the non-descrambling output mode, as shown in FIG. 9, the switch 61 selects the terminal 61a, the switch 62 selects the terminal 62b, and the switch 63 selects the terminal 63a.

  Accordingly, the undescrambled TS supplied from the front end unit 11 to the terminal 61a via the input terminal IN1 is supplied to the terminal 62b via the switch 61. In this case, since the switch 62 selects the terminal 62 b, the TS before descrambling is supplied to the PID detection unit 71 via the switch 62.

  Thereafter, the same processing as that in the descrambling output mode is performed, whereby the TS before descrambling is transmitted and recorded in the DVCR 7.

  Next, in the case of the input mode, as shown in FIG. 9, the switch 61 selects the terminal 61b and the switch 63 selects the terminal 63b. The switch 62 is in a free state.

  Further, in this case, a playback AV / C command is transmitted from the controller 14 to the DVCR 7 via the IEEE 1394 interface 22, whereby playback is started in the DVCR 7, and data recorded there is transferred to the IEEE 1394 interface 22. Will be sent to.

  In the IEEE 1394 interface 22, the data from the DVCR 7 is converted from the format conforming to the IEEE 1394 standard to the original TS (here, partial TS) and supplied to the switch 63 via the input / output terminal IN / OUT. Is done. As described above, the switch 63 selects the terminal 63b. Therefore, the TS from the IEEE1394 interface 22 is supplied to the terminal 61b via the switch 63 and the terminal 63b.

  As described above, the switch 61 selects the terminal 61b. Therefore, the TS supplied via the terminal 63b is output from the output terminal OUT via the switch 61. Here, since the switch 62 is in a free state, the TS output via the switch 61 is not supplied to the PID detection unit 71.

  The TS output from the output terminal OUT is supplied to the descrambler 12, and then descrambled as necessary and supplied to the decoding unit 13.

  The IEEE 1394 interface 22 sends data to be recorded in the DVCR 7 to the DVCR 7 by synchronous communication (Isochronous communication) in the form of a packet for synchronous communication (Isochronous communication), and a command of the DVCR 7 is, for example, The data is transmitted to the DVCR 7 by asynchronous communication (Asynchronous communication) in the form of an asynchronous communication packet defined in IEEE 1394-1995. Further, the IEEE 1394 interface 22 receives the data transmitted by the synchronous communication, the command transmitted by the asynchronous communication, the status, and the like from the DVCR 7 and transmits them to the controller 14 and other necessary blocks.

  As described above, the IRD 5 supplies the pre-descramble TS output from the front end unit 11 or the descrambled TS (descramble data) output from the descrambler 12 to the DVCR 7 and the DVCR 7 outputs the TS. Since the switching unit 21 that supplies data to the descrambler 12 is provided, both the TS before and after descrambling can be output to the DVCR 7, and the data reproduced by the DVCR 7 can be received, and can be decoded as necessary. It can be scrambled and MPEG encoded. That is, data can be input / output flexibly.

  In addition, since the TS output from the front end unit 11 is output from the output terminal OUT via the switch 61 and supplied to the terminal 62b, the user can watch a certain program independently of it. The program can be output to the DVCR 7 which is an external device for recording.

  Furthermore, since the IEEE 1394 interface 22 that functions as an interface between the switching unit 21 and the DVCR 7 is provided, it is possible to exchange AV packets and the like with an external device in parallel with the exchange of TS packets. It becomes possible. In addition, the IRD 5 can be connected to a high-speed IEEE 1394 network, and further, high-speed transmission / reception of TS can be performed with a device connected to the IEEE 1394 network.

  In addition, using the switching unit 21 and the IEEE 1394 interface 22, it is possible to provide an intelligent service to the user using, for example, a GUI (Graphical User Interface) of the IRD 5. That is, for example, when playing back a TS recorded on the DVCR 7 and decoding and displaying it on the IRD 5, the IEEE 1394 interface 22 is made to acquire the status of whether the DVCR 7 is playing data normally, and the data is normal. When not reproduced, the controller 14 can control the switches 61 to 63 so that none of the terminals is selected. As a result, abnormal data is transferred to the descrambler 12 and thus to the decoding unit 13. It is possible to prevent an abnormal screen from being displayed.

  Furthermore, in this case, the user can be notified of the fact by displaying a message that the data is not normally reproduced by using the GUI of the IRD 5.

  Further, since the data parser unit 70 of the switching unit 21 extracts only the TS packets of the necessary channels and outputs them to the outside, for example, each frequency band corresponding to one transponder in the broadcasting station. When a scene shot from a different angle is broadcast on the same program on the channel, the user can record only a scene shot from a desired angle.

  The case where the present invention is applied to a broadcasting system that performs digital broadcasting using a satellite line has been described above. However, the present invention is not limited to a satellite line, for example, a CATV network, the Internet, a terrestrial line, and other transmission media. The present invention can also be applied to the case where digital broadcasting is performed via the Internet.

  In the present embodiment, the IEEE 1394 interface 22 that is a serial interface is provided as an interface between the switching unit 21 and the DVCR 7. However, other serial interfaces may be used. In addition, a parallel interface can be used instead of the serial interface.

  In this embodiment, the DVCR is connected to the IRD 5 as an external device, but the device connected to the IRD 5 as an external device is not limited to the DVCR.

  Furthermore, in the present embodiment, the switching unit 21 extracts a predetermined TS packet from the TS and records it in the DVCR 7. However, the entire TS can be supplied to the DVCR 7 and recorded.

It is a block diagram which shows the structural example of one Embodiment of the broadcast system to which this invention is applied. It is a block diagram which shows the structural example of IRD5 of FIG. It is a block diagram which shows the structural example of the front end part 11 of FIG. It is a block diagram which shows the structural example of the decoding part 13 of FIG. It is a figure which shows the data structure of a transport stream. It is a figure for demonstrating the extraction method of the TS packet of a predetermined channel. FIG. 3 is a block diagram illustrating a configuration example of a controller 14 in FIG. 2. It is a block diagram which shows the structural example of the switching part 21 of FIG. It is a figure which shows the switching method of the switches 61 thru | or 63 of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Transmitter, 2 Antenna, 3 Satellite, 4 Antenna, 5 IRD, 6 Monitor, 7 DVCR, 8 Public network, 10 Reception processing part, 11 Front end part (Reception means), 12 Descrambler (descramble means), 13 Decoding unit, 14 controller, 15 modem, 16 control bus, 20 data interface, 21 switching unit (input / output control unit), 22 IEEE1394 interface (interface unit), 31 tuner, 32 demodulation circuit, 33 error correction circuit, 41 DMUX, 42 to 45 RAM, 46 clock generator, 47 MPEG video decoder, 48 MPEG audio decoder, 49 microcomputer, 51 I / F, 52 CPU, 53 ROM , 54 RAM, 55 internal bus, 60 switcher, 61 to 63 switches (first and second selection means), 71 PID detection unit, 72 comparison unit, 73 register unit, 74 parser

Claims (1)

Receiving means for receiving the scrambled transport stream;
Descrambling means for performing descrambling processing on the scrambled transport stream supplied from the receiving means, and generating a descrambled transport stream;
Interface means;
Input / output control means for controlling input / output between the receiving means or the descrambling means and the interface means;
And a recording and reproducing means for recording and reproducing a transport stream packet from said interface means,
The descrambling means includes:
Judgment means for judging whether or not the transport stream reproduced by the recording / reproducing means is scrambled by referring to a scramble control bit included in a transport stream packet of the transport stream. ,
further,
When the determining means determines that the transport stream reproduced by the recording / reproducing means is a scrambled transport stream, the descrambling is performed on the transport stream reproduced by the recording / reproducing means. Execute the process,
If the determination means determines that the transport stream reproduced by the recording / reproducing means is a descrambled transport stream, the transport stream reproduced by the recording / reproducing means Output without executing descrambling ,
The input / output control means includes
First selecting means for selecting one of the transport stream output from the receiving means or the transport stream supplied from the interface means and supplying the descramble means;
Second selection means for selecting either the selection output of the first selection means or the transport stream output by the descrambling means;
Have
The transport stream PID output from the second selection means is detected, and compared with the PID of the transport stream packet of the program designated by the user. Outputting and supplying to the interface means .

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