JP3149627B2 - Digital information recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital information signal recording / reproducing apparatus, and more particularly, to a digital information recording / reproducing apparatus which records control information by adding it to a recording signal and reproduces the information using the additional information. .

[0002]

2. Description of the Related Art The Journal of the Institute of Television Engineers of Japan Vol. 47, No. 4 (1.
993) as described on pages 494 to 497,
A system for transmitting software such as audio and video via radio waves or cables and recording the data at homes has been considered.

[0003]

In the case of selling or renting audio and video software according to the above-mentioned prior art, there is a problem that the sales destination and the number of rental days must be managed.

An object of the present invention is to solve such a problem,
It is an object of the present invention to provide a digital information recording / reproducing apparatus capable of easily managing a sales destination, rental days, and the like.

[0005]

In order to achieve the above object, according to the present invention, control information such as a user number and a recording date and time is added to a recording signal and recorded. Manage the number of days.

[0006]

During playback, control information such as a user number and a recording date and time is read. If the user numbers are different, no playback is performed. Also, in the case of rental, if a certain period or more has elapsed from the recording date and time, reproduction is not performed. By doing so, it is possible to manage the sales destination, rental days, and the like.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a digital information recording / reproducing apparatus according to the present invention. The digital information recording / reproducing apparatus is roughly divided into a transmitting system 100, a receiving system 200, and a recording / reproducing system 300. 10 is a transmission encoder, 20 is a time axis compressor, 25 is a modulator, 30 is a transmission line, 35 is a demodulator, 40 is a recording encoder, 45 is a switching switch, and 50 is a switch.
Is a rotating drum, 51a and 51b are magnetic heads, 60 is a magnetic tape, 70 is a reproducing decoder, 80 is a receiving decoder,
9 is an output terminal. In the magnetic heads 51a and 51b, (+) indicates a positive azimuth and (-) indicates a negative azimuth.

In FIG. 1, the operation of a transmission system 100 is such that a digital information signal input from an input terminal 1 is encoded by a transmission system encoder 10 in a predetermined format, and the time axis compressor 20 encodes a 1 / n ( In the present invention, n is set to an integer of 2 or more), the time axis is compressed, the transmission rate is increased by n times, modulated by the modulator 25, and transmitted to the transmission path 30.

In the receiving system 200, a signal received via the transmission path 30 is demodulated by a demodulator 35, and the demodulated signal is directly recorded by the recording / reproducing system 300 in a state of being encoded by the transmitting system. It is supplied to the system encoder 40. The recording encoder 40 records and encodes the supplied signal in a format suitable for recording and reproduction.

FIG. 2 is a block diagram showing an example of the configuration of the recording system encoder 40. 41 is a storage circuit, 42 is an interface circuit, 43 is a parity generation circuit, 44 is a recording signal generation circuit, and 301 is a recording signal generation circuit. It is a control information generation circuit.
In the figure, data demodulated by the demodulator 35 of the receiving system 200 is first stored in the storage circuit 41 via the interface circuit 42. FIG. 3A shows this demodulated data. The parity generation circuit 4 3 generates parity from the stored demodulated data to the storage circuit 41, memory circuit 4
1 is stored. In the recording signal generating circuit 4 4 reads the demodulated data and parity stored in the memory circuit 41, adds the ID signal consisting generated control information in the control signal generating circuit 301 and the synchronizing signal, and FIG. 3 (B) Is output as a block format signal as shown in FIG. FIG. 4 shows an example of the configuration of an ID signal. For example, a track number for identifying a recording track, a block number for identifying a position in the track, control information, and error detection and correction of the ID signal. For parity.

The signal coded in the recording system in this way is supplied to the rotary drum 50 via the switch 45.
Magnetic heads 51a, 5
1b, and azimuth-recorded on the magnetic tape 60. FIG. 5 shows the track pattern at this time. The rotation speed of the rotary drum 50 and the running speed of the magnetic tape 60 are set to R1 and V1 as in the prior art, P is the track pitch, and W is the head width of the magnetic heads 51a and 51b. In this embodiment, the head width W is set to be larger than the track pitch P, for example, 1.5 times.

At the time of reproduction, the rotary drum 50 is rotated at the same speed R1 as at the time of recording, and the magnetic tape 60 is rotated at 1 / n of the speed at the time of recording.
And the recorded signals are reproduced by the magnetic heads 51a and 51b. FIG. 6 is a diagram showing a track pattern at the time of this reproduction. A solid line indicates a recorded track pattern, and broken lines indicate magnetic heads 51a, 51a, 5b.
1B shows a scanning locus of FIG. As described above, since the rotating drum 50 is rotated at the same speed R1 as during recording, and the magnetic tape 60 is run at 1 / n speed V1 / n during recording, the scanning pitch of the magnetic heads 51a and 51b is It is 1 / n of the track pitch P, and the scanning angle is slightly shifted.
Scanning is performed n times per track. In this embodiment, n is set to 3 in order to simplify the explanation. W
Indicates the head width of the magnetic heads 51a and 51b.
The head width (W) is set to be larger than the track pitch (P), for example, 1.5 times.

FIG. 7 shows the structure of the control signal. The program number is information indicating the number of the program in the tape, and the time information is information indicating the elapsed time in the tape and in the program. The type is information indicating the type, such as whether the digital information signal to be recorded is sold or rented. This information may be further subdivided according to whether the sold information is sold only to a specific user, the number of days to rent, and the like. The recording date and time is the date and time at the time of recording, and the user number is the registration number of the recording user and is stored in the receiving system 200 or the recording and reproducing system 300.

The control information is distributed and recorded in a plurality of blocks, so that the redundancy can be reduced. Further, as shown in FIG. 8, the information may be recorded in an area different from the digital information signal. In this case, the block configuration is the same as that of the digital information signal recording area, and FIG.
Control information may be recorded in a portion where demodulated data is recorded in (B). The reliability can be improved by writing the control information in a multiplex manner.

In order to receive the service of selling or renting a digital information signal, when the user makes an application to the sender, the sender transmits the digital information signal together with the user number and additional information indicating the type of sale or rental. I do. On the receiving side, the user number in the additional information is identified in the receiving system 200 or the recording / reproducing system 300, and when they match, the information is recorded. At this time,
The type of sale or rental is identified from the additional information, and recorded as information indicating the type in the control information.

FIG. 9 is a block diagram showing an example of the configuration of a reproduction system decoder 70 for performing the processing of the entire reproduction system. 71 is a storage circuit, 72 is a block reproduction circuit, 73 is an error correction circuit, 74 is a reproduction signal output circuit, and 302 is a control signal detection circuit. In the figure, signals reproduced by the magnetic heads 51a and 51b are first input to a block reproducing circuit 72. The block reproducing circuit 72 detects the synchronization signal and the ID signal, and stores them in a predetermined position on the storage circuit 71 based on the track number and the block number in the ID signal. The error correction circuit 73 corrects an error in the reproduced data using the parity stored in the storage circuit 71, and at the same time, generates a pointer indicating an error state and stores the pointer in the storage circuit 71. At this time, data of the same track number and block number is input to the storage circuit 71 n times, but data with the best error state is finally stored by the pointer. Reproduction signal output circuit 74
Then, the data after the error correction processing stored in the storage circuit 71 is read out in accordance with the order of the track number and the block number, and the low-speed data expanded on the time axis is output.

The low-speed data signal subjected to the reproduction-system decoding processing as described above is sent to the reception system 200, and the reception-system decoder 80 de-encodes the data in the transmission system. The signal decoded into the original digital information signal is supplied to an output terminal 9.
Output.

By arranging the receiving-system decoder 80 after the recording-reproducing unit 300, instead of arranging it in this way, the receiving-system decoder 80 can perform low-speed processing.

The control signal detection circuit 302 determines whether or not reproduction is to be performed by identifying the control information. For example, in the case of information that has been sold, if the user numbers match according to the sales form, that is, the information can be reproduced only on the recording device and cannot be reproduced on other devices. In the case of rented information, the recording date and time and the rental period are compared, and if the information has passed the rental period, it cannot be reproduced. This control may be performed by the receiving system 200. In this case, the control signal reproduced by the recording and reproducing system 30 0 outputs the reception system 200.

FIG. 10 is a block diagram showing another embodiment of the digital information recording and reproducing apparatus according to the present invention. It is an example. In the figure, 15 is a scrambler, 52a and 52b are magnetic heads, 75 is a descrambler, 101, 102 and 103 are input terminals, 111 and 112 are A / D converters, 121 and 1
22 is an information amount compressor, 201 and 202 are information amount decompressors,
211 and 212 are D / A converters, 221, 222 and 22
Reference numeral 3 denotes an output terminal. Portions corresponding to those in FIG. The magnetic head 52
In (a) and (52b), (+) indicates a positive azimuth and (-) indicates a negative azimuth.

In the transmission system 100, an image signal input from an input terminal 101 is converted into an A / D signal by an A / D converter 111.
/ D conversion, and the information amount is compressed by the information amount compressor 121 to an appropriate rate. The audio signal input from the input terminal 102 is subjected to A / D conversion by the A / D converter 112, and the information amount is compressed to an appropriate rate by the information amount compressor 122. The A / D-converted and information-compressed image signal and audio signal are time-division multiplexed by the transmission encoder 10 together with the independent data input from the input terminal 103.
And encoded, and are polarized by the scrambler 15. Hereinafter, this polarized signal is time-axis-compressed to 1 / n by the time-axis compressor 20 as in the embodiment of FIG.
The signal is modulated by the modulator 25 and sent out to the transmission path 30.

In the receiving system 200, as in the embodiment of FIG.
A signal received via the transmission path 30 is demodulated by a demodulator 35 and demodulated data is supplied to a recording encoder 40 of the recording / reproducing system 300.

In the recording / reproducing system 300, the supplied demodulated data is recorded and encoded by the recording system encoder 40, and two magnetic heads 51 a, 51 are switched via a switching switch 45.
b, 52a, and 52b, and two-channel azimuth recording is performed on the magnetic tape 60. These two sets of magnetic heads 51
The recording frequency can be reduced to に よ り by two-channel recording using a, 51b, 52a, and 52b.
The rotation speed of the rotary drum 50 and the traveling speed of the magnetic tape 60 are set to, for example, R2 and V2.

At the time of reproduction, the rotary drum 50 is rotated at the same speed R2 as at the time of recording, and the magnetic tape 60 is rotated by 1 / n of that at the time of recording.
And the recorded signal is reproduced by a pair of magnetic heads 51a and 51b. In the present embodiment, the time axis compression coefficient n is set to be sufficiently large (originally, it is desirable that n is large). Even in one-channel reproduction by one set of magnetic heads 51a and 51b, n / 2 times per track. Since the trace can be made, the reproduction decoder 7
By performing the same processing as in the embodiment of FIG. 1 at 0, sufficient data reproduction is possible. Thus, there is an effect that only one system of the reproduction system is required and the circuit scale can be reduced.

The receiving system 200 receives the signal decoded by the reproducing decoder 70, deciphers the signal confidential in the transmitting system by the descrambler 75, and converts the signal encoded in the transmitting system by the receiving decoder 80. Decode and separate image signal, audio signal and independent data. The separated image signal and audio signal are respectively supplied to the information amount expander 201,
The data is expanded to the original information amount by the D / A converter 2.
D / A conversion is performed by the output terminals 221 and 212,
Output from 222. The separated independent data is output from the output terminal 223.

FIG. 11 shows the structure of the control signal of the embodiment shown in FIG. The scramble information is information necessary for descrambling. Normally, this information is
0 is stored. By storing the scramble information as control information and outputting the scramble information reproduced at the time of reproduction to the receiving system 200 and performing descrambling, the recorded information can be reproduced even if the scramble is changed. .

In the case of rented information, if the scramble is changed periodically and the scramble information is not recorded in the control information, the information after a certain period of time cannot be descrambled. This also allows the rental period to be managed.

[0029]

As described above, according to the present invention, in a system for selling or renting audio or video software or the like via radio waves or cables, the sales destination and rental period can be easily managed. can do.

[0030]

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a digital information recording / reproducing apparatus according to the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a recording encoder according to the present invention.

FIG. 3 is a diagram showing input / output signals of the recording encoder shown in FIG. 2;

FIG. 4 is a diagram illustrating a configuration example of an ID signal.

FIG. 5 is a diagram showing a track pattern at the time of recording in the embodiment of FIG. 1;

FIG. 6 is a diagram showing a track pattern at the time of reproduction in the embodiment of FIG. 1;

FIG. 7 is a diagram illustrating a configuration example of a control signal.

FIG. 8 is a diagram showing another embodiment of a control signal recording method.

FIG. 9 is a block diagram showing a configuration example of a reproduction encoder according to the present invention.

FIG. 10 is a block diagram showing another embodiment of the digital information recording / reproducing apparatus according to the present invention.

FIG. 11 is a diagram illustrating an example of a configuration of a control signal according to the embodiment of FIG. 10;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Transmission system encoder, 15 ... Scrambler, 20 ... Time axis compressor, 25 ... Modulator, 35 ... Demodulator, 40 ... Recording system encoder, 41 ... Storage circuit, 42 ... Interface circuit, 43 ... Parity generation Circuit, 44: Recording signal generation circuit, 50: Rotating drum, 51a, 51b, 52a, 52
b: magnetic head, 60: magnetic tape, 70: reproduction decoder, 71: storage circuit, 72: block reproduction circuit, 73:
Error correction circuit, 74: reproduction signal output circuit, 75: descrambler, 80: reception system decoder, 111, 112 ... A /
D converter, 121, 122 ... information amount compressor, 201, 2
02: information amount expander, 211, 212 ... D / A converter,
301: control signal generation circuit, 302: control signal detection circuit.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Nobutaka Amada, Incorporated No. 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Video Media Research Laboratory, Hitachi, Ltd. (72) Inventor Shigeru Yamazaki 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa (56) References JP-A-5-258463 (JP, A) JP-A-5-304680 (JP, A) JP-A-60-159564 (JP, U) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) G11B 20/10

Claims (4)

(57) [Claims] 1. A digital information recording / reproducing apparatus for recording / reproducing a digital information signal, comprising: generating control information including information indicating a date and time when the digital information signal is recorded; and adding the control information to the digital information signal. Recording means for recording the digital information signal, and reproducing means for detecting the control information when reproducing the digital information signal and reproducing only when a predetermined period has not elapsed from the recorded date and time. Recording and playback device. 2. The digital information signal is polarized information, the control information includes information for depolarizing, and at the time of reproduction, the digital information signal is depolarized by using the control information. 2. The method according to claim 1, wherein
2. A digital information recording / reproducing apparatus according to item 1. 3. A digital information reproducing apparatus for reproducing a digital information signal recorded with control information including information indicating a date and time when the digital information signal is recorded, wherein the control information is reproduced when the digital information signal is reproduced. Wherein the digital information signal is reproduced only when a predetermined period has not elapsed from the date and time when the digital information signal was recorded. 4. The digital information signal is polarized information, the control information includes information for depolarizing, and the control information is used to depolarize the digital information signal. The digital information reproducing apparatus according to claim 3, wherein