JP4547097B2 - Digital signal recording / reproducing apparatus and digital signal recording / reproducing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for recording / reproducing digital signals such as digital broadcasts, and more particularly to a digital signal recording / reproducing apparatus in the case where there is a restriction on recording or duplication thereof by a right holder.
[0002]
[Prior art]
Due to the recent digitization of broadcasting and AV recording equipment, unlike conventional analog equipment, recording and copying are possible without degradation. On the other hand, a method has been proposed in which usage permission information for restricting recording or copying is added to a digitized AV signal and the like, and the creation of recording or copying is restricted in accordance with this usage permission information. The rights of rights holders are restricted.
[0003]
As an example of this usage permission information, EMI (Encryption Mode Indicator) in DTCP (Digital Transmission Content Plotting) using IEEE 1394-1995 is known. IEEE 1394 is a standard for a high-speed serial bus, and transmits AV digital data and the like in packets. In this packet, there is 2-bit information defined as EMI in DTCP as usage permission information. EMI indicates that copying is prohibited in the case of 11, and copying is permitted only once in the case of 10, and 00 indicates that copying can be freely performed. EMI 01 represents a copy that is allowed to be copied only once but has already been copied.
[0004]
For example, if prohibition of program duplication is specified in broadcasting, if the receiver that receives the program and the digital recording device are connected by IEEE 1394 with DTCP installed, if the receiver has EMI of 11, the digital recording device is prohibited from duplicating. Judgment is made and recording is not performed. As a result, when the right holder permits only viewing of the broadcast, the recording can be restricted. Also, for example, when the right holder has permitted to record a broadcast once and view it, if the EMI is set to 10 at the receiver, the digital device can record and then reproduce it. In this case, by changing the EMI to 01 and outputting, it is possible to permit viewing but not to record again.
[0005]
As described above, it is possible to copy without degradation by digitizing an AV signal or the like, but at the same time, usage permission information can be added to protect the rights of the right holder.
[0006]
[Problems to be solved by the invention]
Although it is possible to protect the rights of the right holder by the above-described conventional technology, for example, when the copy prohibition is designated as the usage permission information, in the case of television broadcasting, the program is viewed during the broadcast time of the program. However, if a phone call or a visitor is received while watching the program, it will be impossible to see the middle of the program.
[0007]
As a method for solving this problem, as described in Japanese Patent Application Laid-Open No. 2000-149417, there is known a method in which even a non-duplicatable program is recorded once and erased during reproduction. However, if the program is not played back, the recorded program remains forever, and the rights of the right holder are not sufficiently protected.
[0008]
Also, in the field of computers, a trial period is set for a program, and it will operate during the trial period set from the time the program is installed, but it will not work after the trial period, and it can be used by entering a password etc. What is known. An example of this is disclosed in JP-A-7-319689. This is sufficient to determine whether or not the program can be operated, but in recent years, there is a recording that is not limited to a program unit such as continuously recording a broadcast on a large-capacity hard disk and playing it back. In such a case, if the recording start date / time is handled as the trial start time, it may not be possible to reproduce the part recorded immediately before. It is not enough for the device to perform the reproduction.
[0009]
An object of the present invention is to enable viewing of a digital broadcast after interruption when viewing a digital broadcast to which usage permission information has been added, according to the convenience of the viewer while protecting the usage permission information. An object of the present invention is to provide a digital broadcast recording / reproducing apparatus.
[0010]
[Means for Solving the Problems]
  The above object can be achieved by, for example, the configuration described in the claims.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram showing the configuration of an embodiment of a digital broadcast recording / reproducing apparatus of the present invention. In FIG. 1, 110 is a receiving means, 120 is a control means for controlling the receiving means 110, and 130 is a temporary recording / reproducing means for temporarily recording and reproducing a digital signal received by the receiving means 110. Taking the digital broadcast receiver as an example, the receiving unit 110 includes, as main components, a tuner 111 that receives and selects an input signal from an antenna and the like, and a demodulation unit 112 that demodulates a signal selected by the tuner 111. Desired from error correction means 113 for error correction of the demodulated signal, descrambler 114 for canceling scrambling for limited reception after error correction, and a signal multiplexed with video / audio / other data after descrambling It has demultiplexing means 115 for separating signals and a video / audio decoder 116 for decoding the separated video / audio signals.
[0016]
The control unit 120 receives necessary signals from the components 111 to 116 of the receiving unit 110 and controls them. Further, the control unit 120 further stores information on video / audio / data to be temporarily recorded / reproduced. A recording management means 121 for managing, a clock 122 having date and time information, and a counter 123 for accumulating time for measuring elapsed time are provided.
[0017]
Next, the temporary recording / reproducing management process shown in FIG. 1 will be described with reference to an operation flow diagram. 2 and 3 are diagrams showing an example of the operation flow of the temporary recording / reproduction management process. FIG. 2 is a diagram showing the time of temporary recording, and FIG. 3 is a diagram showing the case of reproducing the temporarily recorded digital signal.
[0018]
The temporary recording in FIG. 2 will be described using the configuration in FIG. 1. In the clock confirmation step 202, it is determined whether or not the clock 122 from the temporary recording start step 201 is operating. It is recorded in the recording management means 121 in the date and time recording step 203. When the clock 122 is not operating, it is recorded in the recording management means 121 that the date and time information is not set. Simultaneously with this date / time information recording, the counter 123 is started at the counter start step 204 to measure the elapsed time, the elapsed time is accumulated at the count-up step 205, and is continuously recorded in the recording management means 121 at the counter value recording step 206. .
[0019]
Next, in the case of reproducing the temporarily recorded digital signal, in FIG. 3, it is determined whether or not the clock 122 is operating in the reproduction start instruction step 301 in the clock confirmation step 302. Date / time information is acquired in the current date / time acquisition step 303, and if the clock 122 is not operating, no date / time information is present. In a counter value acquisition step 304, a counter value representing the elapsed time that has been accumulated since the start of recording is acquired. Based on the acquired current date and time and the counter value and the recording start date and time recorded in the recording management means 121 at the start of recording, the playback restriction determination step 305 determines the playback condition of the temporary recording. If the reproduction is not allowed to proceed to the start step 306, the process proceeds to the reproduction impossible step 307 to control reproduction / non-reproduction from the temporary recording / reproducing means 130.
[0020]
Subsequently, some examples of the reproduction condition determination in the reproduction restriction determination step 305 are shown in FIGS. 4 to 6 and will be described below.
[0021]
FIG. 4 is a diagram showing an example of the reproduction restriction determination of FIG. 410 shows the program being broadcast in chronological order, and a movie 411 is broadcast as a 120-minute program from 21:00 to 23:00. While watching this movie 411, for example, a telephone arrives at 21:30, instructs recording start 420, and the viewing is interrupted. After 421/15, the recorded digital signal is reproduced, and from where it was interrupted. Trying to watch 432. At this time, from the current date and time 21:45 acquired in the current date and time acquisition step 303, the counter value 15 minutes acquired in the counter value acquisition step 304, and the recording start date and time 21:30, the reproduction restriction is determined as follows. Do.
Date and time at playback request-Recording start date and time ≤ Temporary recording permission time (Formula 1)
Counter value ≤ Temporary recording permission time (Formula 2)
If both of these expressions are true, reproduction is permitted, and if at least one of the expressions is false, reproduction is not permitted.
[0022]
For example, assuming that the temporary recording permission time is 60 minutes, when the recorded data is played back and the user wants to watch 432 from where it was interrupted, the determinations of equations 1 and 2 are both true, and the playback restriction determination step 305 It is determined that playback is possible, and the process proceeds to playback start step 306, where viewing is possible. Here, the temporary recording permission time may be a predetermined time, or may be transmitted by broadcast as one piece of program information transmitted simultaneously with video / audio data and the like.
[0023]
Next, while watching the movie 411, for example, there is a visitor at 21:30, instructing the recording start 420, and stopping the viewing, 22:45 after 422/75 has elapsed, from 21:30 where it was interrupted When playback and viewing 442 are to be performed, the determination is performed in the same manner as described above, and the determination result of both types becomes false, and playback from 420 is not performed when interrupted at 21:30. In this case, the reproduction restriction determination step 305 performs the following determination process.
Date and time at the time of playback request-Temporary recording permission time <Program broadcast end time (Equation 3)
Based on this determination, it is determined that playback is possible from the time point 424 and the broadcast time 21:45 by going back the temporary recording permission time 60 minutes from the playback request time 22:45. As a result, when the maximum elapsed time 423/60 for which temporary recording is permitted has elapsed, it is determined that viewing 452 can be performed from the location recorded at 21:45, and the process proceeds to reproduction start step 306. Although not shown in the figure, if the interruption time is long and Equation 3 becomes false, the reproduction is impossible and the process proceeds to the reproduction impossible step 307.
[0024]
FIG. 5 is a diagram showing another example of the reproduction restriction determination of FIG. The broadcast program is the same as the example in FIG. 4 and is given the same number. In this example, the movie 411 is temporarily recorded from the beginning, and the movie 511 is temporarily recorded. When viewing is interrupted and 521/45 has elapsed since the start of recording and then viewing 531 is performed from the point of interruption, both equations 1 and 2 are true, and the movie 511 can be viewed from the beginning. Next, when the recorded digital signal is reproduced at 22:30 after 522/90 has elapsed and the viewing 541 is performed from the point where it was interrupted, both expressions 1 and 2 become false, and the determination of expression 3 is entered. . Assuming that 524/60 of the temporary recording permission time goes back from the reproduction request time 22:30, it is determined that the reproduction is possible from the time of the broadcast time 21:30, and the maximum permitted elapsed time 523/60 has passed. : 30, it is determined that viewing 551 can be performed, and the process proceeds to a reproduction start step 306 to perform reproduction.
[0025]
FIG. 6 is a diagram showing still another example of the reproduction restriction determination of FIG. A program 610 that shows a broadcasted program in time order is 610, and a program 611 is broadcast as a 30-minute program from 19:00 to 19:30. This program is temporarily recorded, and the program 612 is temporarily recorded. When viewing is interrupted and the recorded digital signal is reproduced from 20:00 after 621/60 after recording starts and viewing 631 is performed from where it was interrupted, it is the same as the above example. it can.
[0026]
Next, in the case of viewing 641 at 20:35 after 622 of 95 minutes from the start of recording, the power is turned off from 19:30 when the temporary recording is completed to 20:35 after 60 minutes. The counter 123 is not operating and the count value is 30 minutes. Therefore, when a reproduction request is made at 20:35, Expression 2 is true, but Expression 1 is false, and the evaluation of Expression 3 is entered. When 624/60 of the temporary recording permission time is traced back from 20:35 at the time of the reproduction request, it becomes 19:35, and since the broadcast end time 19:30 of the program has passed, the program reproduction 651 is not reproduced.
[0027]
In this example, the case has been described in which time information multiplexed and transmitted together with video / audio data and the like at 20:35 when the power is turned on can be acquired and the clock 122 is set correctly. When the power is turned on, the time information is set in the clock 122, and the date and time are correctly started, the recording start date and time may be compared with the current date and time to correct the count value of the counter 123. Needless to say.
[0028]
When the time information cannot be acquired at the time when the power is turned on at 20:35 and the clock 122 is not set, the expressions 1 and 3 cannot be evaluated. In this case, as a determination method and process, when time information is acquired and reproduction is disabled until the clock 122 operates correctly, and when the count process of the counter 123 is stopped, the time information is acquired and the clock 122 operates correctly. There are three cases where the reproduction is disabled and the counting process of the counter 123 is performed and the elapsed time is continuously measured, and the reproduction restriction determination is performed only by the evaluation of Expression 2 based on the count value of the counter 123.
[0029]
Any of these processes can be selected. As with the temporary recording permission time, a predetermined process may be used, or which process is selected by broadcasting as one of the program information transmitted simultaneously with video / audio data. It may be transmitted as information instructing whether to do.
Here, in the case where reproduction is not possible when the time information cannot be acquired and the clock 122 is not operating correctly, the counter 123 is not necessary, and the evaluation of Expression 2 may not be performed in each processing flow example.
[0030]
However, it is difficult to distinguish whether the state in which the power is interrupted and time information cannot be acquired as in this example is intentional for the purpose of illegal viewing or an accident caused by a thunderstorm or heavy snowfall. For this reason, determining that playback is not possible when the clock 122 is not operating correctly may be that playback is not possible at the time when the weather information is sent and time information can be acquired. It is not preferable.
[0031]
Therefore, if either one or both of the recording start date and time and the playback request date and time are not yet determined, whether or not playback is possible is determined by Equation 2. When the recording starts, the counter 123 continues to count up during the operation of the receiver even after the recording is completed. Therefore, the elapsed time of the temporary recording inside the receiver is integrated. In order to ensure that the recording permission time is consumed, there is a point in time when reproduction is impossible, and the rights of the right holder can be protected.
[0032]
In this example, the case where time information is multiplexed and transmitted together with video / audio has been described. However, as seen on current VTRs and televisions, the time setting can be temporarily recorded by the user. Later, even if the current time is set to a past time for the purpose of unauthorized viewing and Equation 1 is true, the elapsed time of temporary recording can be determined by Equation 2, so that unauthorized viewing can be prevented.
[0033]
As described above, according to the present embodiment, it is possible to allow and reproduce the broadcast program temporarily recorded in the temporary recording / reproducing means only during the period permitted as the temporary recording permission time. While viewing the rights that cannot be copied, the viewing is not restricted to the broadcast time in real time, and can be viewed according to the convenience of the viewer.
[0034]
FIG. 7 is a diagram showing another example of the operation flow of the reproduction management process for temporarily recorded data. The temporary recording is the same as in FIG.
[0035]
The playback management process flow example of FIG. 7 differs from the playback process flow example of FIG. 3 as a playback start instruction, in which a recording start time is not designated as an implicit start position, but a playback start date and time is indicated. Date and time instruction step 701, the instructed reproduction start date and time, the counter value indicating the accumulated elapsed time acquired in the counter value acquisition step 304, the current date and time information acquired in the date and time acquisition step 303, and the record management at the start of recording The reproduction restriction determination step 705 for performing reproduction restriction determination based on the recording start date and time recorded in the means 121 is used, and the others are the same as those in the example of the processing flow in FIG.
[0036]
In the following, the difference will be described with reference to an example of the reproduction restriction determination in FIG.
[0037]
In FIG. 8, the broadcast program is the same as the example of FIGS. 4 and 5, and a movie 411 is temporarily recorded from the beginning (movie 511). The viewer was watching 831 and 841 until past 21:30, and the viewing was interrupted for some reason, at 22:15, when viewing again by playing the recorded digital signal, A continuation 832 for re-viewing the continuation from 21:30 and a re-viewing 842 for re-viewing from the first 21:00 are shown.
[0038]
In a continuation 832, the viewer instructs playback from 21:30 based on the memory that the viewer has watched until 21:30. Based on the date / time information 22:15 acquired in the current date / time acquisition step 303 and the counter value 75 minutes acquired in the counter value acquisition step 304, the reproduction restriction is determined as follows.
Date and time at playback request-playback start instruction date and time ≦ temporary recording permission time (formula 1 ')
Counter value−counter value at playback start instruction time ≦ temporary recording permission time (formula 2 ′)
If both are true, playback is allowed, and if at least one is false, playback is not allowed.
[0039]
For example, if the temporary recording permission time is 60 minutes, in the case of continuation 832, both determinations are true, the reproduction restriction determination step 705 determines that reproduction is possible, and the process proceeds to the reproduction start step 306 so that viewing is possible. Here, the counter value at the playback start instruction time point is derived from the recording start date and time 21:00 and the playback start instruction date and time 21:30 by the following expression.
[0040]
Counter value at playback start instruction time = reproduction start instruction date / time-recording start date / time (formula 4)
In this example, 30 minutes is derived as 21: 30-21: 00: 00. The temporary recording permission time shown here may be a predetermined time as in the example of FIG. 3, or may be transmitted by broadcast as one piece of program information transmitted simultaneously with video / audio data or the like. .
[0041]
Next, re-viewing 842 is a case where the viewer tries to watch again from the beginning, and when a reproduction instruction is issued from 21:00, determination processing is performed in the same manner as in continuation 832, and expressions 1 ′, 2 ′ Both are false and the re-viewing 842 from 21:00, which is the beginning of the movie, is not reproduced. In this case, the reproduction restriction determination step 705 performs the following determination process.
Date and time at the time of playback request-Temporary recording permission time <Program broadcast end time (Equation 3)
By this determination, it is determined that playback is possible from the time of the broadcast time 21:15 by going back 824/60 of the temporary recording permission time from the playback request time 22:15. As a result, when the maximum allowed elapsed time 824/60 has elapsed, it is determined that viewing 852 can be performed from the location recorded at 21:15, and the maximum allowed elapsed time 60 minutes It is the same as the example of the processing flow of FIG. 3 that it is determined that the user can re-view 852 from 22:15 when 823 has elapsed and the process proceeds to the reproduction start step 306.
[0042]
Similarly, although not shown in the figure, if the interruption time is long and Equation 3 is false, the reproduction is disabled and the process proceeds to the reproduction disabled step 307. Furthermore, in this example, when the reproduction request date and time is not yet determined, whether or not reproduction is possible is determined by Expression 2 '. Since the counter 123 continues to count up during the operation of the receiver after the recording is started, the elapsed time of the temporary recording inside the receiver is accumulated, so that the temporary recording permission time is ensured even if illegal viewing is performed. Because there are times when it cannot be regenerated, it is possible to protect the rights of the right holder. Similarly to the example of the processing flow of FIG. 3, even if the time of the clock 122 can be set to a past time by some means at the time of playback request, the elapsed time of temporary recording can be determined by the counter value. Can be prevented.
[0043]
As described above, according to the present embodiment as well, it is possible to realize and permit reproduction of a broadcast program or the like temporarily recorded in the temporary recording / reproducing means only during the period permitted as the temporary recording permission time. While protecting the rights that cannot be duplicated, the viewing is not restricted to the broadcast time in real time, and viewing according to the convenience of the viewer becomes possible. Furthermore, in this embodiment, since it is possible to specify the date and time at which playback is to be started, it is not restricted by the recording start time, and a playback restriction determination is made at a place where re-viewing is desired due to interruption or the like while maintaining a state where recording is continued for a long time. It becomes possible.
[0044]
FIGS. 9 and 10 are diagrams showing another example of the operation flow of the temporary recording / reproducing management process. FIG. 9 is a diagram showing the time of temporary recording, and FIG. 10 is a diagram showing the case of reproducing the temporarily recorded digital signal. is there.
[0045]
In the operation flow of the temporary recording management process of FIG. 9, the operation flow of this process is different from the operation flow of the process of FIG. 2. The counter 123 is not controlled at the start of recording, but the counter value is set at the start of recording. The other points are the same in that they are recorded in the recording management means 121. The counter 123 always counts up and records the counter value as reception control while the receiver is operating.
[0046]
Next, in the operation flow of the process for reproducing the temporarily recorded data in FIG. 10, the operation flow of this process is different from the other process flows in that the current date and time, the current counter value, and the recording start date and time The other points are the same as the other processing flow examples in that a reproduction restriction determination step 1005 for performing reproduction restriction determination using the counter value at the start of recording is used, and the same numbers are assigned. Hereinafter, different points will be described.
[0047]
In the operation flow of this process, the counter 123 always counts up, records the counter value C1 at the recording start time, and uses the counter value C2 at the reproduction request time to counter the expression 2 or 2 ′ in another example. C2-C1 is used as the value.
As a result, in the case of an operation flow of other processing, if there are two programs that are temporarily recorded, for example, two counters must be managed. Even if there are a plurality of programs, it is only necessary to manage one counter.
[0048]
FIG. 11 is a diagram showing still another example of the operation flow of the reproduction management process for the temporarily recorded digital signal. The temporary recording is the same as in FIG.
[0049]
The reproduction management processing flow example of FIG. 11 is similar to the processing flow example of FIG. 7 in that the reproduction start instruction step 301 of FIG. 10 is replaced with the reproduction start date / time instruction step 701 of FIG. The designated reproduction start date and time is also the point that the reproduction restriction is determined in addition to the conditions, and the others are the same as the processing flow example of FIG.
[0050]
As described above, according to this embodiment, it is possible to permit and reproduce the broadcast program temporarily recorded in the temporary recording / reproducing means only during the period permitted as the temporary recording permission time as the use permission information. Since it can be realized, the viewing can be performed according to the convenience of the viewer without being restricted by the real time of the broadcast time, while protecting the right that the right holder cannot copy. Furthermore, according to the present embodiment, it is possible to perform temporary recording management of a plurality of programs using the counter value only by always performing count-up management of one counter.
[0051]
Therefore, even a broadcast program whose use permission is clearly specified by the right holder can be recorded and played back for a predetermined period of time or for a short time designated each time. There is no loss of rights, and even if the viewing is interrupted by telephone or the like, the viewer can watch it again from the location where it was interrupted. It is possible to enjoy broadcast programs without being bound.
[0052]
【The invention's effect】
According to the present invention, when a digital broadcast to which usage permission information is added is being viewed, the suspended digital broadcast can be viewed at the convenience of the viewer while protecting the usage permission information. A digital broadcast recording / reproducing apparatus can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an embodiment of a digital broadcast recording / reproducing apparatus of the present invention.
FIG. 2 is a diagram illustrating an example of an operation flow of a temporary recording management process.
FIG. 3 is a diagram showing an example of an operation flow of a reproduction management process when reproducing the digital signal temporarily recorded in FIG. 2;
4 is a diagram showing an example of reproduction restriction determination in FIG. 3. FIG.
FIG. 5 is a diagram showing another example of the reproduction restriction determination of FIG. 3;
6 is a diagram showing still another example of the reproduction restriction determination in FIG. 3. FIG.
FIG. 7 is a diagram illustrating another example of an operation flow of a reproduction management process for a temporarily recorded digital signal.
FIG. 8 is a diagram illustrating an example of reproduction restriction determination in FIG. 7;
FIG. 9 is a diagram illustrating another example of the operation flow of the temporary recording management process.
FIG. 10 is a diagram showing an example of an operation flow of a reproduction management process when reproducing the digital signal temporarily recorded in FIG. 9;
FIG. 11 is a diagram showing still another example of the operation flow of the reproduction management process for the temporarily recorded digital signal.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 110 ... Reception means, 111 ... Tuner, 112 ... Demodulation means, 113 ... Error correction means, 114 ... Descrambler, 115 ... Demultiplexing means, 116 ... Video / audio decoding means, 120 ... Control means, 121 ... Recording management means, 122 ... Clock, 123 ... Counter, 130 ... Temporary recording / reproducing means, 201 ... Recording start step, 202 ... Clock confirmation step, 203 ... Current date and time recording step, 204 ... Counter start step, 205 ... Count up step, 206 ... Counter value recording Step 301: Playback start instruction step 302 ... Clock confirmation step 303 ... Current date / time acquisition step 304 ... Counter value acquisition step 305 ... Playback restriction determination step 306 ... Playback start step 307 ... Playback disabled step 701 ... Playback start position instruction step, 70 ... playback restriction determination step, 904 ... start counter value recording step, 1005 ... playback restriction determination step, 1105 ... playback restriction determination step.

Claims (2)

In the digital signal recording and reproducing apparatus for recording and reproducing digital signals which are transmitted with the use permission information for restricting duplication,
Receiving means for receiving the digital signal,
Temporary recording / reproducing means for performing temporary recording and reproduction when the use permission information prohibits copying;
And time management means for managing the current time by the time of time information,
An elapsed time management means for managing the elapsed time from the time of recording;
Control means for managing the temporary recording and reproduction based on the current time and the elapsed time;
Wherein, when the digital video and temporarily storing the audio signal reproduced by the temporary recording means, wherein the current time and the elapsed time managed at least minutes, the elapsed from the start of the record when the time has not exceeded the predetermined temporary recording permission time, record the digital video audio signal is a renewable, when the elapsed time from the start of record has exceeded the temporary recording permission time Is a digital signal recording / reproducing apparatus that disables reproduction of digital video / audio signals recorded before the temporary recording permission time before the time when reproduction is requested. Receiving a digital signal that is transmitted with the use permission information for restricting duplication,
A previous SL License information and temporary record when the copy inhibition digital signal recording and reproducing method of performing the reproduction,
To manage the current time by the time of time information,
Manage the time elapsed since recording,
When the digital image temporarily recorded audio signal reproduction, the currently managing the time and the elapsed time of at least minutes, a temporary recording permission time during which the elapsed time from the start of the record is predetermined when not exceeded, recording the digital video audio signal is a renewable, when the elapsed time from the start of record has exceeded the temporary recording permission time, the from the temporary time playback is requested A digital signal recording / reproducing method characterized in that a digital video / audio signal recorded before a time before the recording permission time cannot be reproduced.

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