JPH0748278B2 - Recording / playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention records and reproduces an audio signal or an image signal, and in particular, a recording and reproducing apparatus capable of applying a predetermined limitation in recording and reproducing. Regarding

(Prior Art) Currently, various types of recording and reproducing audio signals or image signals, such as tape-shaped recording media, disk-shaped recording media, and card-shaped recording media, are taken as examples of only dynamic recording media. Various recording / reproducing systems such as a magnetic system and an optical system have been considered for a recording medium, and each of them has been put into practical use according to its use. These recording / reproducing devices
In addition to having high fidelity recording / reproducing capability, it is also desired that the operability and usability are excellent, and the functions required by the user are within a certain range, for example, there is a hindrance to the society. It is desirable to prepare as much as possible within the range not included.

In the various recording / reproducing apparatuses as described above, generally, a recording medium and a recording / reproducing apparatus exist separately, and if the recording / reproducing apparatuses of the same type, the recording medium used for them can record or reproduce. It is designed to be compatible. However, in some cases, the compatibility may prevent the user from easily recording information.

For example, when an information source is recorded in a predetermined recording medium for sale for commercial use, if the purchaser duplicates it, the recording medium on which the information is recorded and the recording medium on which the information source is recorded have the same value. become. Therefore, if such duplication is performed in large quantities for commercial purposes by utilizing the compatibility of the recording / reproducing apparatus, as a result, the value of the recording medium in which the information source is recorded is greatly reduced. Moreover, the more faithful the copy, the smaller the need for a recording medium containing an information source.

In order to avoid such a situation, it can be said that some measure is taken to prohibit copying. However, in the conventionally considered means as described below,
It was unsatisfactory for the user side. That is,
The conventional copy prohibition method is to insert a signal representing a predetermined prohibition code together with the information source into a recording medium for recording the information source and record the information source. On the recording / reproducing apparatus side, the prohibition code is included in the transmission signal for recording. If detected, it is designed to stop the recording function. For example, when the transmission format when an information source (which is a digital signal) is reproduced is an aggregate of blocks (consisting of 1 to m bits) as shown in FIG. 7, each block or a predetermined block is specified. The position (n-th bit) is assigned as a flag indicating the prohibition of recording operation: "0" and the permission: "1", and in the recording / reproducing apparatus to which the reproduction signal is input, the above flag (or a combination of the flags is used). Code that can be)
Is detected, and if it indicates the prohibition of the recording operation, the recording function is stopped. The recording function can be stopped by various methods such as disconnecting the signal path. If such measures are taken uniformly for all recording / reproducing apparatuses of the same type, duplication can be prohibited for an information source with a prohibition code.

However, in the conventional method as described above, the duplication of the information source with the prohibition code is completely prohibited, and therefore, the recording that does not reduce the value of the recording medium containing the information source, for example, the user's private use is prohibited. It is also impossible to record for the purpose.

In addition, there is a recording / reproducing apparatus that scrambles a recording signal based on a specific keyword at the time of recording and records the signal, and at the time of reproducing, by inputting a keyword that coincides with that at the time of recording, the scramble is released to enable normal reproduction. It was

However, in such a conventional method, in order to descramble the reproduction signal, the user has to input the same data as the character data input at the time of recording at the time of reproduction, which not only deteriorates the usability but also makes the scramble descrambling. There is a problem that if the character data that is used as the password is forgotten, the reproduction becomes impossible. Further, there is a recording / reproducing apparatus in which a device on the reproducing side is provided with means for detecting whether or not the keyword at the time of recording matches the keyword at the time of reproducing. However, in such a conventional method, since the reproducing device side is provided with the keyword detecting means and the keyword matching means,
There was a risk that the keywords could be deciphered and there was a problem.

Also, apart from the problem of dealing with commercial information sources, as a user's request for a recording / reproducing apparatus, it is not possible for other people to easily copy or reproduce, except for the user's own recording. You may want a recording function like this. However, such a conventional recording / reproducing apparatus that does not restrict duplication at all or adopts the above-described duplication prohibition method cannot satisfy such a user's request.

(Problems to be Solved by the Invention) As described above, in the conventional recording / reproducing apparatus, since the copy limitation is too complete or in the unlimited state, the recording / reproducing operation in the personal use desired by the user is performed. In some cases, it was not satisfactory, and as a result, the use of the recording / reproducing apparatus was limited.

The present invention has been made in consideration of such problems,
It is an object of the present invention to provide a recording / reproducing apparatus capable of selectively prohibiting duplication under a certain restriction so as to satisfy the personal use of the user.

[Structure of the Invention] (Means for Solving Problems) A recording / reproducing apparatus according to the present invention includes means for generating a specific identification signal on the recording side, and detection of a predetermined input signal to achieve the above-mentioned specific It has a means for encoding at least a part of the recording signal using the identification signal, and a means for decoding the signal encoded by the specific identification signal on the reproducing side.

(Operation) According to the above means, when recording an information source whose copying is restricted, an input signal indicating that is detected and a specific identification signal (for example, a code signal unique to each recording / reproducing device, etc.) ) Is used to encode the information source or its ancillary signal, and when reproducing the signal recorded in this way, it is possible to decode the recording signal provided that the specific identification signal can be known. Has become.
By doing so, unless the specific identification signal used at the time of recording is known (or if it cannot be generated), it cannot be reproduced by a recording / reproducing apparatus completely different from the recording / reproducing apparatus used for recording, and it becomes impossible to reproduce. A certain limit can be given.

(Example) Hereinafter, the Example of this invention is described.

1 to 4 relate to an embodiment of the present invention. First, FIG. 1 shows the structure of the recording side of the recording / reproducing apparatus in the present embodiment, in which an information source for recording is inputted to an input terminal (11). Here, the information source is a formatted digital signal as shown in FIG. 7,
There is a restriction flag indicating that there is a restriction of duplication at the n-th bit of the block: "0", no restriction: "1".
As such an information source, for example, a signal reproduced from a tape-shaped recording medium in which information is recorded in advance, that is, a soft tape may be assumed. Therefore, the input signal including the restriction flag is supplied from the input terminal (11) to the detection and determination circuit (12) and the encoder (13). The detection and determination circuit (12) detects the restriction flag from the input signal and determines whether the detected restriction flag is "0" or "1". The encoder (1
3) control. That is, the detection and determination circuit (12) causes the encoder (13) to perform the encoding operation on the input signal when the restriction flag is “0” (restricted) (rank R). Here, an identification signal peculiar to this generator is supplied to the encoder (13) from the identification signal generator (14), and if the determination result is rank R, the identification signal is used by the encoder (13). The input signal that has been processed is scrambled. Then, the signal processed by the encoder (13) becomes a signal different from the input signal before processing, is guided to the output terminal (15), and is recorded on the recording medium by a recording circuit (not shown). On the other hand, when the detection and determination circuit (12) determines that the restriction flag is “1” (no restriction) (rank F), the encoder (13) does not execute the encoding operation using the identification signal. The input signal is led to the output terminal (15).

Next, the structure of the reproducing side of this embodiment will be described with reference to FIG. A signal read from a recording medium by a reading device (not shown) is given to an input terminal (16) and supplied to a recording rank determination circuit (17) and a decoder (18). Here, whether or not the recording rank determination circuit (17) has recorded in the case of the above rank R at the time of recording from the state of the read signal,
Alternatively, it is determined whether the data was recorded in the case of rank F.
That is, if the recorded signal is through the above encoding operation, it is necessary to decode it at the time of reproduction. Therefore, the recording rank determining circuit (17) determines whether or not the encoding operation is performed, and the encoding operation is performed ( In the case of rank R), the decoder (18) is made to perform a decoding operation (descramble, etc.). Decoder at that time (18)
The decoding operation in Fig. 1 is the same as the identification generator (14) in Fig. 1.
Converted to the same normal signal as before encoding only when the identification signal is the same as the identification signal used for the encoding operation when recording the read signal. You can As described above, since the identification signal generated by the identification signal generator (14) is a signal peculiar to the generator, the signal applied to the input terminal (16) is the identification signal generator (14 ) Is not encoded by the identification signal generated by), that is, the reproducing device and the recording device are not the same, the decoding (18) performs a wrong decoding operation,
As a result, a meaningless signal is output. on the other hand,
When the recording rank determination circuit (17) determines that the rank is F, the decoder (18) guides the input signal to the output terminal (19) without executing the above decoding operation, and a normal reproduction is performed by a reproduction circuit (not shown). Processing is performed.

The present embodiment basically has the above-mentioned configuration, and various realizing means can be considered for each component in FIGS. 1 and 2 from well-known techniques. Therefore, I will briefly introduce these specific examples. Figure 3 shows
1 shows an example of an identification signal generator (14), and when a specific code signal, for example, a signal of several bits such as "010011 ... 01" is used as an identification signal, a terminal for transmitting each bit of the code signal ( The above specific code signal is obtained by selectively inserting a jumper wire or a switch (23) between the ground terminal (22) and the ground terminal (22). The jumper wire or the switch (23) is inserted randomly at the time of manufacturing, and a code signal specific to each recording / reproducing apparatus can be generated by this. Another means is to store a specific code signal in a read only memory (ROM). As the ROM, any of an electrically programmable EPROM, a write once ROM that can be electrically written only once, and a mask ROM that determines a code at the time of circuit design can be used.

FIG. 4 shows a specific example of the encoder (13). If the above-mentioned code signal is output from the identification signal generator (14), the code signal is input to the pseudo random sequence (PN) generator (24), and the PN signal with the code signal as an initial value is used. Is generated. The PN signal is given to one input end of the exclusive OR circuit (25), and the input signal for recording is given to the other input end from the input terminal (26) of the encoder (13). As a result, the signal output from the exclusive OR circuit (25) is guided to the output terminal (27) as a scrambled signal which is completely different from the original input signal. Further, the circuit of FIG.
8) Can also be used as That is, if the same code signal is given to the PN generator (24) at the same timing as at the time of encoding, the read signal is descrambled by the PN signal whose initial value is the code signal, and the exclusive OR circuit (25 The output signal of) becomes a signal equal to the input signal before encoding. Here, as a method of matching the timings at the time of encoding and at the time of decoding, for each predetermined block of the recording signal, for example, for each track in the recording / reproducing method using a rotary head for a tape-shaped recording medium, at the beginning of each track It is an easy way to initialize. It should be noted that such scrambling and descrambling are executed in the rank R, and in the rank F, for example, an input signal is directly derived from another input terminal (not shown) to the output terminal, or PN is generated. It suffices to take measures such as stopping the operation of the container (24). Further, even in the case of rank R, the above scrambling and descrambling do not necessarily have to be performed on all input signals. For example, the input signal is a main signal and an auxiliary signal for controlling recording and reproduction of the main signal. If so, it may be performed only for one or a part of them. Other than the above, there are many conceivable configurations that can be used as the encoder (13) or the decoder (18).

In addition, as a determination method in the recording rank determination circuit (17) in FIG. 2, when it is difficult to determine from the signal itself of the portion to be encoded, a certain data is separated from the signal to be encoded at the time of encoding. Is added and recorded, and for example, a signal such as "11" with encoding operation, "00" without encoding operation, etc. is inserted into a part of the recording format, and this is detected during playback to determine the rank. There is.

According to this embodiment, when an information source whose duplication is restricted is recorded by the above-mentioned configuration, the information source is encoded based on a specific identification signal, that is, an identification signal unique to each recording / reproducing apparatus. The signal thus recorded cannot be reproduced as a normal signal unless it is decoded based on the specific identification signal, that is, it is reproduced by the same device as the recording device. Therefore, it is not possible to make a commercial copy that can be reproduced by any recording / reproduction device, and it is possible to place strict restrictions on the reproduction, while at the same time the user makes a copy for personal use. Is not prohibited, and the user's request can be satisfied. Further, in the above embodiment, the presence or absence of a plurality of restrictions is automatically discriminated from the information source, and the recording / reproducing apparatus itself responds selectively, so that the usability is excellent without the user having to bother. There is.

In the above embodiments, the case where the information source is a digital signal has been described as an example. However, even if it is an analog signal, the basic configuration is the same, and it is possible to deal with it by changing each component. it can. For example, when a special signal is added to the signal band of the information source with respect to the information source whose copying is limited, the detection and determination circuit (12) in FIG. 1 detects the presence or absence of the special signal and makes the determination. Depending on the result, the same processing as in the above embodiment may be performed in an analog manner.

5 and 6 show another embodiment of the present invention. The same parts as those in the previous embodiment are designated by the same reference numerals and the description thereof will be omitted. In the above embodiment, if the identification signal used for encoding and the identification signal used for decoding do not match at the time of reproduction, the decoder (18) will consequently perform an incorrect decoding operation. At this time, if the signal output from the decoder (18) is, for example, an audio signal, a signal that causes an unpleasant sound,
There is a possibility that the signal may interfere with the output circuit. In order to prevent such a situation, it has been conventionally known to perform muting on an unnecessary output signal.
In view of this, the present embodiment is provided with a configuration for determining whether or not the identification signal at the time of encoding and the identification signal at the time of decoding are matched so that muting can be performed appropriately.

That is, as shown in FIG. 5, the recording side has the same encoder (13) as in the previous embodiment and a combiner (31) at the subsequent stage as an encoding means, and an identification signal generator (1
The identification signal output from 4) is also given to the combiner (31), and the identification signal is added to the recording signal for recording. Such processing is easily possible if both the recording signal and the identification signal are digital. Then, on the reproducing side, as shown in FIG. 6, the identification signal detection circuit (32) connected to the input terminal (16) detects the added identification signal from the read signal, and the comparison circuit (33). The detected identification signal is compared with the identification signal output from the identification signal generator (14). Then, when the comparison result does not match, the muting circuit (34) provided in the subsequent stage of the decoder (18) causes the decoder (1
8) Cut off the output. Further, by displaying the comparison result of the comparison circuit (33) on a display device (not shown), it is possible to give the user a warning of refusal of reproduction. By doing so, not only the same effects as those of the previous embodiment can be obtained, but also a more practical recording / reproducing apparatus can be provided.

As another embodiment, the following may be considered although not shown. The detection / judgment circuit (12) in the above embodiment judges the presence / absence of the copy restriction from the signal included in the information source. In addition to this, the copy / restriction is judged by judging the signal from the keyboard of the recording / reproducing apparatus. It is also possible to execute the processing of. By doing this, even when recording an information source whose replication is not restricted, it is possible to restrict it by the user's will.
It is also possible for a user to make it impossible for others to easily reproduce personally recorded content other than for himself to use.

Further, the identification signal generator (14) of the above embodiment is built in the recording / reproducing apparatus.
It may be formed as a separate unit from the recording / reproducing apparatus and detachable from the recording / reproducing apparatus main body. If you do this,
For recording media recorded with copying restricted,
It is possible to slightly relax the restriction range in which reproduction can be performed only by a recorded device, and it is possible to restrict reproduction only when the identification signal generator unit used at the time of recording is owned. Such a procedure is effective when the user manages a plurality of recording / reproducing devices individually.

In the present invention, the identification signal generator used at the time of recording does not have to be always used at the time of reproduction. In short, what is encoded by a special method is only a special method corresponding thereto. It suffices if it can be decoded, and the signal used in the special system is the identification signal. Therefore, it is not always necessary to use the same identification signal for encoding and decoding. For example, if the decoder itself is designed in a special way,
The signals used therein may be related but not exactly the same as the signals used during encoding.

In addition to the above, various embodiments of the present invention are conceivable, and similar effects can be obtained without departing from the scope of the present invention.

[Effects of the Invention] As described above, the recording / reproducing apparatus of the present invention can selectively prohibit duplication under certain restrictions, and thus the recording / reproducing operation in a personal use desired by the user. Can be satisfied.

[Brief description of drawings]

FIG. 1 is a block diagram showing the structure of the recording side of a recording / reproducing apparatus in an embodiment of the present invention, FIG. 2 is a block diagram showing the structure of the reproducing side of the same embodiment, and FIG. 3 is the same embodiment. FIG. 4 is a circuit diagram showing an example of the identification signal generator (14) of FIG. 4, FIG. 4 is a circuit diagram showing an example of the encoder (13) and the decoder (18) of the embodiment, and FIGS. FIG. 7 is a block diagram showing the configuration on the recording side and the configuration on the reproducing side of a recording / reproducing apparatus in another embodiment of the invention, and FIG. 7 is a conceptual diagram showing its format as an example of an information signal input to the recording / reproducing apparatus. . 12 …… Detection and judgment circuit, 13 …… Encoder 14 …… Identification signal generator, 17 …… Record rank judgment circuit, 18 …… Decoder.

Claims (4)

[Claims] 1. An identification signal generating means for generating a specific identification signal for each recording / reproducing apparatus, an information source having first control information indicating presence / absence of copy restriction, and detecting the first control information. First control information detecting means, and the first control information detecting means detecting the first control information
First determining whether or not there is the copy restriction based on the control information of
Control information determining means, scrambling means for encoding and scrambling at least a part of the information source using the identification signal according to the determination result of the first control information determining means, and the scrambling means. Second control information indicating whether or not scramble processing has been performed, recording means for recording a recording signal output from the scramble means on a recording medium, and reproduction for reproducing the second control information and the recording signal from the recording medium. Means, a second control information detecting means for detecting the second control information reproduced by the reproducing means, and a second control information detecting means for detecting the second control information detected by the second control information detecting means.
And a descrambling unit for decoding and descrambling the recording signal by using the identification signal according to the control information. 2. The recording / reproducing apparatus according to claim 1, wherein the identification signal generating means is provided detachably from the main body of the recording / reproducing apparatus. 3. An identification signal generating means for generating a specific identification signal for each recording / reproducing apparatus, an information source, and first control information indicating the presence or absence of copy restriction according to a predetermined key operation. Control information adding means for adding to the source; scrambling means for encoding and scrambling at least a part of the information source using the identification signal according to the first control information; and scrambling processing by the scrambling means. Recording means for recording on the recording medium the second control information indicating whether or not and the recording signal output from the scramble means, and a reproducing means for reproducing the second control information and the recording signal from the recording medium, Control information detecting means for detecting the second control information reproduced by the reproducing means, and a control information detecting means for detecting the second control information detected by the control information detecting means. A recording / reproducing apparatus comprising: a descrambling unit which decodes the recording signal by using the identification signal and performs a descrambling process according to the second control information. 4. The recording / reproducing apparatus according to claim 3, wherein the identification signal generating means is provided detachably from the recording / reproducing apparatus main body.