JPH01229464A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent taking a digital copy in the 3rd generation from the 2nd generation by providing a copy control signal discriminating part for adding a copy inhibiting bit and 2nd category code to a digital output signal at the time of regenerating a copy control subcode signal of a prescribed value. CONSTITUTION:The subject device is constituted in such a manner that when a recording substance in the 2nd generation is reproduced, the copy inhibiting bit '0' and also a 1st category code DAT dot deciding the suitableness of the digital copy based on the presence of the copy inhibiting bit are added to the digital output signal. Consequently, the subsequent digital copies cannot be executed. By this method, a digital copy for the 2nd generation is feasible from a record as an analog copy from the 1st generation, but a digital copy for the 3rd generation is not feasible from the 2nd generation, thus limiting the number of generations to this accordingly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a recording/playback device, such as a digital audio tape recorder (hereinafter referred to as DAT), which is capable of converting an analog signal into a digital signal, recording and playing back the signal. It is.

Conventional technology In recent years, standardization of interface specifications for connecting audio devices using digital signals has progressed, and CD players, satellite broadcast reception tuners (hereinafter referred to as BS tuners), etc.
Products equipped with a digital output terminal in addition to an analog output terminal are commercially available. Furthermore, recording and reproducing apparatuses such as DAT, which can convert analog signals from conventional audio equipment into digital signals and record them, as well as directly record digital signals, have been put into practical use.

Hereinafter, a DAT will be described as an example of the above-mentioned recording/reproducing apparatus with reference to the drawings.

FIG. 3 is a connection diagram of audio equipment centered on a conventional DAT, FIG. 4 is a part of a signal format of a digital audio interface, and FIG. 6 is a part of a DAT recording format.

In FIG. 3, 61 is a BS tuner, 61 is a BS tuner,
61D is an analog output terminal and a digital output terminal of the BS tuner 61. 62 is a CD player, 62A
, 82D are analog output terminals and output terminals of the CD player. 63 is DAT, 63A, 63D is D
These are the analog output terminal and digital output terminal of AT63. 64 is an analog audio device such as an FM tuner or an analog record player, and 64 is an analog output terminal of the analog audio device e4.

6s and se are DAT respectively, 65B and 66B are analog input terminals of DAT65 and DAT66, esc
, eθC are digital input terminals of DAT65 and DAT66, and 66m and 66m are DAT66.

Analog output terminal of DAT66, 65D, 66D
This is the digital output terminal of AT65 and DAT66. Digital output terminals e1D and 62D for each device.

Signals are exchanged from the 63D and esD to the digital input terminal esc of the DAT 65 and the digital input terminal of the CAT 66 in a format defined as shown in FIG. As shown in FIG. 4a, two subframes for the left channel and the right channel are constructed during the sampling time of the analog signal. Each subframe consists of 32 bits as shown in Figure 4, and includes a 4-pin synchronization signal,
It is configured to transfer 20 pints of audio data after 4 bits of preliminary data. The remaining four pits are configured to have meaning as one block of 192 bits, as shown in FIG. 4C for channel status as an example. Six bits from bit 0 to bit 5 of the channel status are control bits and indicate the purpose, whether or not digital copying is possible, etc. That is, when bit 2 of the channel status of the signal input to the digital input terminal esc is "O", the DAT 65 cannot perform digital recording. (For example, see "Electronics Life Volume 655, pages 18-19," below, when bit 2 of the channel status is 1T o +1,
(This bit 2 will be referred to as the copy prohibition pit) Compact discs that are copyrighted generally have a signal recorded on them that indicates the prohibition of digital copying, and this compact disc cannot be played back. Then, the copy prohibition bit is output from the digital output terminal. Therefore, when a music source is reproduced, the signal from the digital output terminal 62D of the CD player 62 cannot be recorded by the DAT 65 because of the copy prohibition bit.

In addition, DAT63, DAT65, and DAT66 tapes have a recording format as shown in Figure 6, and the PCM data that encodes the audio signal and the MayyID for playing the PCM data are located in the PGM area at the center of the tape. recorded. There are 12 PGM areas shown in the 6th National Electric Railway.
It consists of 8 blocks, and one block consists of 288 bits as shown in FIG. As shown in FIG. 5C, the main ID is repeatedly recorded nine times from the format ID, ID+, to ID6, ID, one block at a time.

As shown in Figure 5d, when the 2nd pin of the format ID is ``Oo'', that is, if the DAT is an audio recorder, digital copying is possible when the 2nd pin of the format ID is 00''. When it is "10", digital copying is prohibited. In other words, a tape recorded by a DAT user can be digitally copied with ``6'' as ``o o 11,'' but in the case of a soft tape such as a music source, ``10'' must be recorded in ID6. Otherwise, digital copying will not be possible.

However, recording from the analog output terminal 62A of the CD player θ2 to the analog input terminal 65B of the DAT65,
It is not possible to record from the analog output terminal 63 of the AT63 to the analog input terminal 65B of the DAT65, and analog copying of compact discs and DAT soft tapes is possible even though digital copying is prohibited. However, in this case, since the data passes through the D-person conversion circuit of the CD player 62 or the DA conversion circuit of the DAT 63 and the AD conversion circuit of the DAT 65, some deterioration in sound quality can be avoided compared to digital copying. Furthermore, since 6 is ``oo'' on a tape that has been analog-recorded at -degrees as shown in FIG. 5d, it is possible to make unlimited digital copies thereafter.

Problems to be Solved by the Invention As explained above, although conventional DAT allows the freedom of recording for personal enjoyment, compact discs contain a code in the digital signal that prohibits digital copying. Therefore, it is not possible to directly record digital signals, and DAT users are forced to record with analog signals, which degrade the sound quality to some extent.

However, DAT tapes recorded with -degree analog signals are recorded as 'oo' in May 7ID, so unlimited digital copying is possible after that, and compact discs and DAT music soft tapes are analog Although the sound quality deteriorates to some extent during recording, it is possible to create a digital copy without any deterioration in sound quality.Therefore, this poses a problem that poses a huge disadvantage to the music and other software industries. .

In view of the above-mentioned problems, the present invention has been developed to
Even with tapes, the present invention provides a recording and reproducing device that includes a DAT that limits the number of possible digital copies.

Means for Solving the Problems In order to solve the above problems, the recording and reproducing apparatus of the present invention includes an input setting section for selecting analog copy or digital copy, and a reproduction signal copy setting section that takes a predetermined value at the time of analog copying. A copy control signal generation unit that generates a 2-bit copy control subcode signal indicating permission or disapproval, and a first category code that determines whether digital copy is possible depending on the presence or absence of a copy prohibition bit, or digital copy regardless of the presence or absence of a copy prohibition bit. a category code setting unit that can output a second category code that enables It is equipped with a copy control signal discriminating section that should not be added.

According to the above-described configuration, the present invention adds a copy prohibition bit to the digital output signal when reproducing a first generation recorded material that has been analog copied, and the digital copy is performed regardless of the presence or absence of the copy prohibition bit. Since a second category code is added that enables recording, recording becomes possible when this digital output signal is input to the digital input terminal of another DAT, creating a second generation recording. When playing the next 2nd generation recorded material, the digital output signal will be
If a copy prohibition bit is added and a first category code is added that determines whether or not digital copy is possible depending on the presence or absence of a copy prohibition focus, subsequent digital copies will not be possible.

Therefore, it is possible to kill the second generation by digital copying from the analog copy of the first generation, but it is not possible to copy the third generation digitally copied from the second generation, which limits the number of generations to be copied. can do.

EXAMPLE Hereinafter, an example of the present invention will be described using a DAT as an example with reference to the drawings.

1 is an analog input terminal, 2 is a Muro converter, 3 is a digital input terminal, 4 is a digital demodulation circuit that demodulates the digital signal input to the digital input terminal 3, and 5 is an output signal of the Muro converter 2 or the digital demodulation circuit 4. 6 is a recording signal processing circuit that performs interleaving processing to change the temporal arrangement of the digital signal, addition of an error correction code, and addition of an output signal from a subcode encoder 13 (described later); 7 is a recording signal processing circuit for selecting an output signal; A recording amplifier, 8 a recording head, and 9 a magnetic tape. Reference numeral 1o denotes a copy prohibition focus determination unit that determines whether bit 2 of the channel status is 0'' (presence or absence of a copy prohibition bit).

11 indicates whether the category code shown in C in FIG. 4 is a first category code (hereinafter referred to as DATO category code) that determines whether digital copying is possible depending on the presence or absence of a copy prohibition bit, or a signal from DAT. This is a second category code (hereinafter referred to as DAT-C) that allows digital copying regardless of the presence or absence of a copy-prohibited focus, or another code that indicates that the signal is from a category other than DAT. This is a category code determination unit that determines whether

The function 12 of the copy control signal generating section 12 in Table 1 is based on the output signal of the copy prohibition bit discriminating section 10 and the output signal of the category code discriminating section 11. 1 is obtained as shown in Table 1, and in the case of analog recording, 6 is a copy gain signal generating section to1u. 13 is a subcode encoder that creates a subcode including ID6. 14 is
Operation switches including a recording switch, a playback switch, and an input selection switch for switching between recording the signal input to the analog input terminal 1 and the signal input to the digital input terminal 3; 15 is the input selection switch; Control the selection switch according to the
This is an input setting section that controls the value to be '0''.1e
is a recording prohibition setting section that controls the recording signal processing circuit 6 to prohibit recording in the symbol processing circuit function when the copy prohibition bit discriminating section 1o detects the copy prohibition bit and the category code discriminating section 11 detects the DATO category code. It is. 28 is a playback head, 17 is a playback amplifier, and 18
19 is a reproduction signal processing circuit that performs error correction of digital signals and deinterleaving processing to restore the original temporal arrangement;
is a DM converter, and 2o is an analog output terminal. 2
1 is a subcode decoder that obtains signals such as main ID, 2
2 is the output of the subcode decoder 21, so from 6,
This is a copy control signal generating section that outputs commands as shown in Table 2, for example, to a copy prohibition bit setting section 29, which will be described later, and a category code setting section 30, which will be described later.

Table 2 29 shows that when the copy control signal determination unit 22 outputs that the copy prohibition bit exists, bit 2 of the channel status is set to 0.
This is a copy prohibition bit setting unit that sets the value to be +t1n in other cases. 3o is “1100” when the copy control signal determination unit 22 outputs DAT.
0000” and outputs DAT-1, the corresponding 8
This is a category code setting means for setting a category code of a bit. A channel status encoder 23 includes output signals from the copy prohibition bit setting section 29 and the category code setting section 3o. 25 is a digital modulation circuit which obtains digital output signals shown in FIGS. 4a and 4b from the output signal of the reproduced signal processing circuit 18, the output signal of the channel status encoder 23, etc., and 26 is a digital output terminal. 2
7 is a copy control signal generating section 12. Input setting section 15. Recording prohibition setting section 16. Copy control signal determination unit 22. Copy prohibition bit setting section 29. This is a system controller including a category code setting section 3°, and is composed of, for example, a microcomputer 2.

The operation of the DAT configured as described above will be explained below using drawings and tables. FIG. 2 is a flowchart showing part of the processing of the system controller 2a.

First, a case will be described in which a signal input from the analog input terminal 1 is recorded and this tape is digitally copied.

When the input changeover switch of the operation switch 140 is set to analog recording and the recording switch is pressed, it is determined in judgment step 36 in FIG. 2 that the recording switch is pressed, and the process proceeds to judgment step 37. When analog recording is determined in the judgment step 37, the signal is input to the analog input terminal 1 and the AD converter 2 is inputted in the processing step 44.
The signal converted into a digital signal is input to the selection switch. The input setting section 15 controls the selection switch 5 to select the output of the AD converter, and in processing step 45, the copy control signal generation section 12 is informed that ID6 is +0. A control signal is output so that the signal becomes ++. Next, in a processing step 53, the subcode signal including 6 and the output signal of the selection switch 5 are recorded on the magnetic tape 9. The tape recorded in this way is referred to as a first generation tape. When creating a second generation tape by digitally copying a first generation tape, when the playback switch in the operation switch 14 is pressed, the system controller 27 performs determination step 4.
At e, it recognizes that the playback switch has been pressed, and
The reproduction head 28 reproduces the signal recorded on the magnetic tape 9, and the reproduction amplifier 17. The digital signal of the audio signal is inputted to the DA converter 19 and the digital modulation circuit 26 via the reproduced signal processing circuit 18, and the subcode signal is inputted to the copy control signal conversion section 22 via the subcode decoder 21.

In the determination step 47, the copy control determination unit 22:
Therefore, it is determined that 6 is e o 1+1, and in a processing step 48, a command is outputted to add a copy prohibition bit to the copy prohibition bit setting section 29 from Table 2, and in a judgment step 49, a copy control signal is output. The determining unit outputs a command to the category code setting unit 3o to output a category code compatible with DAT-C. In processing step 50, the category code setting unit 3o outputs a command to the channel status encoder 23 to output an 8-bit category code indicating that digital copying is possible regardless of whether or not copying is prohibited. Channel status encoder 23 obtains the signal shown in FIG. 4C. Subsequently, in processing step 64, the digital output decoder 26 converts the output signals of the channel status encoder 23 and the reproduced signal processing circuit 18 into the output signals of FIG. 4a.

A digital signal shown in b is obtained and output from the digital output terminal 26. When connecting this signal to the digital input terminal 3 of another DAT and recording it, set the input selector switch of the operation switch 14 to digital recording and press the recording switch.In judgment step 37, digital recording is set. The input setting unit 15 determines that the output signal of the digital input decoder 4 is input to the recording signal processing circuit 6, and proceeds to a processing step 38, where the input setting section 15 sets the selection switch 5 to input the output signal of the digital input decoder 4 to the recording signal processing circuit 6, and proceeds to a judgment step 39. In judgment step 39, the copy inhibition bit discriminator 1' inputs the output signal of the digital input decoder 4 and checks bit 2 of the channel status.

Bit 2 when playing back the first generation tape is a digital copy prohibition signal, ie, "0", so it is determined that there is a copy prohibition pit, and the process goes to judgment step 40. In judgment step 40, the category Code discrimination section 1
1 inputs the output signal of the digital input decoder 4, checks bits 8 to 15 of the channel status, determines that it is DAT-G, and reaches processing step 42, where the copy control signal generator 12 From Table 1 I
Set D6 to be "10". The tape recorded in this way is referred to as a second generation tape. Similarly, when creating a third generation tape by digitally copying a second generation tape, when the second generation tape is played back, the copy control signal determination unit 22 determines that ID6 is (*1 o 79). Then, the process goes to processing step 48, and the copy prohibition bit setting unit 29 outputs a command to the channel status encoder 23 to set bit 2 of the channel status to "0".Next, the process goes to judgment step 49, so that 6 becomes +10.
I? Therefore, processing step 62 is reached, and the category code setting section 30 sets the channel status encoder DA.
A command is output to set a code of "110oOo00" indicating that it is T. Channel status encoder 23 obtains the signal shown in FIG. 4C. Subsequently, in processing step 54, the digital output decoder 26 obtains the digital signals shown in FIGS. When attempting to record this signal by connecting it to the digital input terminal 3 of another DAT, the copy prohibition pit discriminator 1o determines in judgment step 39 that there is a copy prohibition bit, and in judgment step 4o, the category code discriminator 11 is determined to be DAT. Here, if the channel status signal of the digital input signal includes a copy prohibition bit and the category code is DAT, the recording prohibition setting unit 16 prohibits recording so that digital copying is not possible. If recording is prohibited by, for example, cutting off the signal output from the recording signal processing circuit 6 to the recording amplifier 7, the first
Second generation tapes can be created by digitally copying tapes that have been analog-copied, but third generation tapes cannot be created from second generation tapes.

As described above, when a first generation recorded material that has been analog copied is played back, a copy prohibition bit is added to the digital output signal, and a digital copy is possible regardless of the presence or absence of the copy prohibition bit. Since a category code of 2 is added, this digital output signal is
When inputted to the AT's digital input terminal, recording becomes possible and second-generation recorded materials are created. When playing the next second generation recorded material, the configuration is such that a copy prohibition bit is added to the digital output signal, and a first category code is added that determines whether or not digital copying is possible depending on the presence or absence of the copy prohibition bit. If so, subsequent digital copies cannot be made. Therefore, it is possible to reproduce the second generation by digital copying from records made by analog copying of the first generation, but
The digitally copied third generation cannot be duplicated from the third generation generation, and the number of generations to be copied can be limited.

In addition, in the above-mentioned embodiment, when an analog copy is made, that is, a signal whose sending device cannot be determined is transferred to the DA.
We have explained how to limit the number of copy generations to protect copyright when recording with T, but even when digitally copied using a Muro converter, there is generally a copy prohibition bit in the output signal of the AD converter. Since it is not added, it is possible to record onto DAT from copyrighted materials such as CDs, and subsequent digital copies are possible without limit, causing the same problems as analog copies. Therefore, the number of digital copy generations can be limited in the digital copy using the Muro converter by setting the copy control subcode signal in the same manner as in the analog copy.

Effects of the Invention As described above, the present invention includes an input setting section for selecting analog copy or digital copy, and a 2-pit copy control subcode signal that indicates whether or not a playback signal can be copied, and which takes a predetermined value during analog copying. a first category code that determines whether or not digital copying is possible depending on the presence or absence of a copy prohibition bit, or a second category code that allows digital copying regardless of the presence or absence of a copy prohibition bit. a category code setting section capable of outputting a category code, and a copy control signal determining section for adding a copy prohibition bit and the second category code to the digital output signal when the copy control subcode signal of the predetermined value is reproduced. By providing an analog copy of the first generation, the second generation can be reproduced digitally, but from the second generation, the third generation digitally copied
Generations cannot be duplicated, and the number of copies can be limited. Therefore, there will be no disadvantage to the music and other software industries.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a DAT according to an embodiment of the present invention.
Fig. 2 is a flowchart showing part of the processing of the system controller in Fig. 1, Fig. 3 is a block diagram showing the connection of audio equipment centered on a conventional DAT, and Fig. 4 is a signal diagram of the digital audio interface. Format diagram showing the main parts of the format. FIG. 5 is a format diagram showing the main parts of the DAT recording format. 3...Digital input terminal, 1o...Copy prohibition bit discrimination unit, 11...Category code discrimination unit, -12...Copy control signal generation unit, 1
3...Subcode encoder, 21...
・Subcode decoder, 22...Copy control signal determination section, 23...Channel status encoder, 26...Digital output terminal, 27...System controller, 29... - Copy prohibition pit setting section, 3o...Category code setting section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 4
Figure Huntroll 11000000: OAT

Claims (1)

[Claims] An input setting section for selecting either analog copy, which copies analog signals sent and received between devices, or digital copy, which copies digital signals sent and received between devices; A copy control signal generation unit that generates a 2-bit copy control subcode signal indicating whether or not copying is possible, and a first category code that determines whether or not digital copying is possible depending on the presence or absence of a copy prohibition bit, or regardless of the presence or absence of a copy prohibition bit. a category code setting unit capable of outputting a second category code that enables digital copy; and when the copy control subcode signal having the predetermined value is reproduced, a copy prohibition bit and the second category code are added to the digital output signal; A recording/reproducing device comprising a copy control signal determination unit for adding a code, and limiting the number of generations of subsequent digital copies even if the first generation is an analog copy of a recorded material. .