JP3770595B2 - Recording method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a record how to record a digital broadcast received.
[0002]
[Prior art]
A satellite broadcasting form (digital broadcasting) by digital transmission has already been put into practical use. In this digital broadcasting, a large amount of information is transmitted at a higher speed by a broadcast signal transmitted from a broadcasting station by adopting a high-efficiency compression encoding technology. Is being transmitted. This transmitted information includes video / audio signal information (program information), data broadcast information, program name, and program start / end time such as program selection such as program selection. Service Information) is included.
[0003]
These pieces of information are transmitted by transport streams multiplexed and separated by 188-byte fixed-length transport packets. A code (error code) for detecting an error is added to the transport packet.
[0004]
SI information is stored in the television receiver for displaying a program guide for program selection and program reservation. In the case of SI information, when the received information contains an error, the error rate can be easily determined because the transmission rate is not high by repeatedly receiving this information and including error detection information other than the error code. Correction is possible. Therefore, the SI information is stored after correcting the error.
[0005]
On the other hand, in the case of program information, if an error is included in the received program information, it is corrected by an MPEG (Moving Picture Experts Group) decoder and output to a television receiver as video / audio. In addition, a digital broadcast receiver that records received program information in a recording device such as an HDD (Hard Disk Drive) has been proposed (Japanese Patent Laid-Open No. 2001-268516). In the receiving device incorporating the HDD, although video / audio can be recorded, there has been a problem that the soundness of all data cannot be investigated during recording.
[0006]
[Problems to be solved by the invention]
As described above, since all the data to be recorded is not checked when recording video / audio signals, data that cannot be reproduced is recorded when the recorded data is reproduced. There was a problem of getting worse. In addition, there is a problem that the state of this error is not known during reproduction.
[0007]
The present invention aims to provide a record method selectively storing renewable data by removing unnecessary data, Ru can improve recording efficiency of the recording apparatus.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the recording method of the invention according to claim 1 is characterized in that after receiving a digital broadcast signal and demodulating a transport stream including multiplexed packets carrying at least video information and audio information, In a recording method for recording a desired transport stream so as to be readable to a recording device, the error information of the transport stream obtained based on the number of packets per unit time of transport packets constituting the transport stream Based on this, a transport stream is selectively recorded in a recording device .
[0009]
The recording method of the invention according to claim 2 receives a digital broadcast signal, demodulates a transport stream including multiplexed packets carrying at least video information and audio information, and then records a desired transport stream. In a recording method for readable recording on a device, the transport stream is selectively recorded on a recording device based on transport stream error information obtained based on PSI information in the transport stream. And
[0010]
The recording method of the invention according to claim 3 receives a digital broadcast signal, demodulates a transport stream including multiplexed packets carrying at least video information and audio information, and then records a desired transport stream. In a recording method for readable recording on an apparatus, the transport stream is selectively recorded on a recording apparatus based on error information of the transport stream obtained based on PAT in the transport stream. To do .
[0011]
The recording method of the invention according to claim 4 receives a digital broadcast signal, demodulates a transport stream including multiplexed packets carrying at least video information and audio information, and then records a desired transport stream. In a recording method for readable recording on a device, the transport stream is selectively recorded on a recording device based on error information of the transport stream obtained based on the PMT in the transport stream. To do .
[0017]
With this configuration, selectively storing renewable data by removing unnecessary data, it is possible to provide a record method that can improve the recording efficiency of the recording apparatus.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an outline of a digital broadcasting system in which a digital broadcasting television receiver according to a reference technique as a background of the present invention is used. Transmission information as a data group is modulated from the digital broadcasting station 1 by the modulation stage 2 and transmitted to each television receiver 3 as a digital broadcasting signal. The transmission information includes video information, audio information, PSI (Program Specific Information) information, SI (Service Information) information, and data broadcast information.
[0019]
Video information and audio information constitute program content information. The PSI information is data for identifying a broadcast channel and includes a PAT (Program Association Table) and a PMT (Program Map Table). The SI information is program information used for program reservation such as a program name and a program start / end time.
[0020]
These pieces of information are transmitted as a transport stream. MPEG2 transport streams, as shown in FIG. 2 (a), are multiplexed and separated by the transport packet 4 fixed length of 188 bytes. As shown in FIG. 2B , the data of the transport packet 4 includes a header portion 4a indicating packet control information, an adaptation field 4b indicating dynamic state change information of an individual stream, and video and audio data. It is composed of a payload (48 bytes) 4c indicating data.
[0021]
This header portion 4a includes a synchronization byte (8 bits) 4d as a synchronization signal, an error indicator (1 bit) 4e indicating the presence or absence of a bit error in the packet, and a new PES (Packetized Elementary Stream) packet. Unit start indication (1 bit) 4f indicating starting from the payload of the packet, transport packet priority (1 bit) 4g indicating the importance of the packet, stream identification information, and attributes of the individual stream of the packet Includes a PID (Packet Identification) (13 bits) 4h.
[0022]
The header section 4a also includes a scramble control (2 bits) 4i indicating the presence / absence and type of the payload of this packet, an adaptation field control (2 bits) indicating the presence / absence of an adaptation field and the presence / absence of the payload in this packet. 4j includes a cyclic counter (4 bits) 4k which is information for detecting whether or not a packet having the same PID is partially discarded in the middle.
[0023]
The configuration of the television receiver 3 will be described with reference to FIG. FIG. 3 is a block diagram illustrating the configuration of the television receiver 3. The television receiver 3 includes a demodulation stage 11 that demodulates a received broadcast signal, a transport stream processor (hereinafter referred to as TSP) 12 that decodes a transport stream (transport signal) output from the demodulation stage 11, An MPU (Micro Processor Unit) 14 that processes a transport signal output from the TSP 12 to the first signal line 13, a data output from the MPU 14, and a recording device 15 that includes an HDD (Hard Disk Drive).
[0024]
The MPU 14 has a RAM (Randam Access Memory) 14a for temporarily storing data to be recorded in the recording device 15. Based on an error indicator in the TS packet, error information indicating the presence or absence of an error in the TS packet signal is transmitted to the MPU 14 from the TSP 12 to the MPU 14 via the second signal line 16.
[0025]
Recording is performed on the recording device 15 in the state of the transport stream shown in FIG. At the time of reproduction, the signal recorded in the recording device 15 is output to the third signal line 17 under the control of the MPU 14 and applied to an MPEG decoder (not shown). Thereafter, it is organized into video / audio signals and finally output to a cathode ray tube and a speaker (not shown).
[0026]
Next, a procedure for recording data in the recording device 15 in the television receiving device 3 will be described with reference to FIG. When the MPU 14 receives a recording instruction and starts recording processing, the TSP 12 first detects the presence or absence of an error based on the TS packet error indicator (step 1). The detected error information is transmitted from the TSP 12 to the MPU 14. If there is no error in the TSP packet according to this error information, the MPU 14 performs a writing process to the recording device 15 (step 2). This writing process is performed by writing a certain amount of data (TS packet) output from the TSP 12 in the RAM 14 a and then writing it to the recording device 15.
[0027]
When an error is detected from the error information, the MPU 14 observes the occurrence of an error per unit time (step 3). Data sent from the TSP 12 during this observation period is temporarily stored in the RAM 14a. When the occurrence of an error per unit time exceeds a certain limit, the data in which the error has occurred is not finally written into the recording device 15, but a data management information area provided in the recording device 15 The duration of error occurrence, for example, 5 minutes 10 seconds to 6 minutes 50 seconds is recorded as a part of the recorded data management information (step 4). This error information is used when the data stored in the recording device 15 is reproduced, such as displaying this information on a monitor. Here, the data management information includes information necessary for data management such as the entire recording time in addition to the error information described above.
[0028]
When the error occurrence per unit time is within a certain limit, the data is written into the recording device 15 and the error occurrence duration is recorded in the data management information area (step 5).
[0029]
The presence or absence of the end of recording is detected (step 6). To continue recording, return to the beginning. If the recording is finished, the process is terminated.
[0030]
In the above-described reference technique , the recording method for selectively recording data by detecting the error state of the received data using the error indicator in the TS packet has been described .
Hereinafter, the selective writing of data to the recording apparatus by detecting the error state of the received data by the fluctuation of the number of TS packets per unit time according to the embodiment of the present invention will be described with reference to FIG. Light up.
[0031]
FIG. 5 is a flowchart showing a procedure for detecting the presence or absence of an error state in the received data based on the number of TS packets. First, the number of packets per fixed time is detected to obtain the number of packets per unit time (step 11). The presence or absence of data of the number of packets per unit time of previously recorded data is confirmed (step 12). The difference between the number of packets per unit time recorded last time and the number of packets per unit time detected this time is calculated (step 13). When there is no previously recorded data, that is, when data is recorded for the first time, the number of packets per unit time obtained in step 11 is recorded in the data management information area of the recording device (step 14) and data is recorded. Is treated as normal. Thereafter, a writing process to a recording apparatus (not shown) is performed.
[0032]
Next, a sudden change in the difference in the number of packets obtained in step 13 is monitored. That is, the packet number difference value obtained in step 13 is compared with the maximum rate obtained from the PMT in the PSI information (step 15). If it is determined in step 15 that the maximum rate has been exceeded, it is monitored whether or not this state continues for a predetermined time (step 16). If it continues for a certain time or more, it is judged as an error state and a write prohibition process is performed. That is, the data determined to be in an error state is not written to the recording device, and the time information of the data that has not been written is written in the data management information area of the recording device. If the continuation is within a certain time in step 16, the process returns to step 11 to perform a predetermined process.
[0033]
If it is determined in step 15 that the maximum rate is not exceeded, it is verified whether the value of the number of error packets with respect to the number of received packets is equal to or smaller than a predetermined value (step 17). As a result of the verification, if the value is equal to or less than a predetermined value, a writing process to a predetermined recording device is performed as a normal state. On the other hand, if it is not less than the predetermined value, the process proceeds to step 16 to determine the continuation state of the state, and then a predetermined process is performed.
[0034]
Furthermore, another embodiment will be described. In another embodiment, the presence or absence of an error in the reception state is detected by monitoring the PSI information included in the packet of the transport stream for the state of the received data. That is, as described above, since the PSI information includes a large number of video and audio individual streams in the transport stream, which program is selected from a plurality of programs (programs) and which TS packet is extracted. This is information on how to decode. From the content, the television receiver repeatedly (periodically) acquires this PSI information at regular intervals. Therefore, by monitoring this PSI information, it can be used as an index for determining the data reception state. This PSI information includes a PAT representing information in units of TS packets and a PMT representing information in units of services (programs), and the data reception state can be known from the reception state of any one of these pieces of information.
[0035]
A procedure for recording data in the recording device 15 in the television receiver 3 using the PSI information will be described with reference to FIG. When the MPU 14 receives a recording instruction and starts recording processing, the TSP 12 first acquires PSI information (step 21). When the PSI information is acquired, it is determined that the received data is in a normal state, and the MPU 14 performs a writing process to the recording device 15 (step 22). Since the writing process is the same as that described in the above embodiment, the description thereof is omitted here.
[0036]
When the PSI information cannot be acquired in step 21, the time that cannot be obtained is observed and it is determined whether or not it is within a certain time (step 23). Data sent from the TSP 12 during this observation period is temporarily stored in the RAM 14a. When the time during which PSI information cannot be obtained exceeds a certain limit, the received data is determined to be in an error state, and the data during this period is not finally written into the storage device 15. However, the duration of the error occurrence is recorded as a part of the data management information in the data management information area provided in the recording device 15 (step 24).
[0037]
When the time during which the PSI information cannot be obtained in step 23 is within a predetermined time, the data is written into the recording device 15 and the error occurrence duration is recorded in the data management information area (step 25). .
[0038]
The presence / absence of recording is detected (step 26), and when recording is continued, the process returns to the beginning. If the recording is finished, the process is terminated.
[0039]
【The invention's effect】
According to the invention described in detail above, it is possible to provide by removing unnecessary data selectively storing renewable data, record how recording efficiency Ru can improve the recording apparatus.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a broadcasting system in which a television receiver according to a reference technique as a background of the present invention is used.
FIG. 2 is a schematic diagram showing a transport stream transmitted in a broadcasting system.
FIG. 3 is a block diagram showing an outline of a television receiver according to a reference technique as the background of the present invention.
FIG. 4 is a flowchart showing a broadcast signal recording method according to a reference technique as the background of the present invention.
5 is a flowchart showing a recording method of a broadcasting signal according to the implementation of the embodiment of the present invention.
FIG. 6 is a flowchart showing a broadcast signal recording method according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Digital broadcasting station , 2 ... Modulation stage , 3 ... Television receiver , 4 ... Transport packet , 11 ... Demodulation stage , 12 ... Transport stream processor , 13 ... 1st signal line , 14 ... MPU , 15 ... recording device, 16 ... second signal line, 17 ... third signal line.

Claims (4)

  In a recording method for receiving a digital broadcast signal and demodulating a transport stream including multiplexed packets carrying at least video information and audio information, and then recording the desired transport stream in a readable manner on a recording device, The transport stream is selectively recorded on a recording device on the basis of error information of the transport stream obtained based on the number of packets per unit time of transport packets constituting the transport stream. Recording method.   In a recording method for receiving a digital broadcast signal and demodulating a transport stream including multiplexed packets carrying at least video information and audio information, and then recording the desired transport stream in a readable manner on a recording device, A recording method comprising: selectively recording a transport stream on a recording device based on error information of the transport stream obtained based on PSI information in the transport stream.   In a recording method for receiving a digital broadcast signal and demodulating a transport stream including multiplexed packets carrying at least video information and audio information, and then recording the desired transport stream in a readable manner on a recording device, A recording method comprising: selectively recording a transport stream on a recording device based on error information of the transport stream obtained based on the PAT in the transport stream.   In a recording method for receiving a digital broadcast signal and demodulating a transport stream including multiplexed packets carrying at least video information and audio information, and then recording the desired transport stream in a readable manner on a recording device, A recording method comprising: selectively recording a transport stream on a recording device based on error information of the transport stream obtained based on the PMT in the transport stream.

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