KR19980014890A - Magnetic recording / reproducing apparatus using user code and control method thereof - Google Patents

Abstract

A magnetic recording and / or reproducing apparatus using a user code and a control method thereof are provided. A cryptographic key is given to a set so that a third party can not illegally copy a program recorded by the user, or a cryptographic code is recorded on a part of the tape In order to solve the problem that unauthorized viewing in other sets can not be prevented, it is necessary to provide formatting means for matching compressed data to a format for recording on a tape When the user wishes to prohibit unauthorized viewing, records in a second recording format in which an arbitrary user's password code is assigned, and when recording in the second recording format, A track recording order in which data is shuffled and divided into a plurality of tracks and recorded The user code given by the user at the time of recording is compared with the currently input user code, and if deemed to match, the de-formatting is performed according to the order of the original track number in one frame, This is advantageous in that it is useful for storing and managing data by a user code when a DVCR is used as a data storage (Srorage).

Description

Magnetic recording / reproducing apparatus using user code and control method thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital VCR, and more particularly, to a magnetic recording and / or reproducing apparatus and its control method of a DVCR using a user code.

Hereinafter, a DVCR data recording / reproducing apparatus according to the related art will be described with reference to the accompanying drawings.

1 is a block diagram showing a recording / reproducing apparatus of a digital VCR according to the related art,

FIG. 2 is a diagram showing a format of a track and a frame of a general digital VCR, and FIG. 3 is a diagram illustrating a recording format of an A / V signal and an additional signal of a digital VCR according to the related art.

1, an input signal processing unit 10, an A / D conversion unit 11, a shuffle unit 12, an external output control unit 13, a data conversion and signal processing unit 14, A reproduction amplifier 15 and a recording / reproducing section 17. [

The input signal processing unit 10 separates color signals and luminance signals of a video signal input from a camera or other video input / output device and applies the separated signals to an A / D converter 11.

The A / D converter 11 converts the applied analog video signal into a digital video signal and inputs the digital video signal to the shuffle unit 12.

The shuffling unit 12 shuffles the input digital image signal and displays the shuffling image on the image display device 16 in response to a control signal of the external output control unit 13, .

The data conversion and signal processing unit 14 compresses the video signal through a discrete cosine transform (DCT) and a variable length encoding (VLC), and then adds an ECC code for error correction.

After performing the recording coding for recording, the data is amplified and recorded in the recording / reproducing section 17 to prevent the recording and reproducing outputs from being lowered in the recording and reproducing amplifier 15.

Here, the above process can be reversed when the video signal recorded in the recording / reproducing section 17 is reproduced.

At this time, the standard of the input video signal is a Y: Cr: Cb signal inputted in 4: 2: 2 according to the CCIR 601 standard.

Here, Y is a luminance signal representing brightness of an image, and Cr and Cb are color difference signals representing a color of an image.

And, 4: 2: 2 means that information of 24 bits per pixel is normally allocated, but means for reducing color information by using the human eye which is not so sensitive to color is often used.

At this time, what is not reduced in color information is called 4: 4: 4, and reduction in half in the lateral direction is called 4: 2: 2.

That is, in the case of 4: 2: 2, the standard frequency of Y is set to 13.5 MHz and Cb and Cr to 6.75 MHz in order to reduce the color information in half in the horizontal direction.

If the sampling frequency of Y is 4, then Cb and Cr become 2, so that the name is 4: 2: 2.

The amount of information of the video signal input to the CCIR 601 standard is about 125 Mbps so that the amount of information is so large that the information can not be recorded as it is.

Therefore, it is compressed to about 1/5 through DCT and VLC, and processed by the data conversion and signal processing unit 14 with an information amount of about 25 Mbps.

At this time, the image is shuffled by the shuffle unit 12 before compression so as to minimize deterioration of image quality during compression and recording / reproduction of the image.

However, even in the case of a DVCR, since the correlation between the original image and the recording track must be temporally and spatially matched in order to implement special reproduction, that is, variable-speed reproduction or the like, the compressed signal after shuffling is suitable before the error correction code is added Format as shown in FIG. 3 again.

3 illustrates a recording method of audio / video and subcode signals of a DVCR. In FIG. 3, one frame of data in the DVC standard, which is a standard of a digital VCR of the world, is 10 tracks for NTSC, 12 In the case of NTSC, the relation between the video signal and the track is shown in a segment.

That is, conventionally, as shown in FIG. 3, one frame of audio, video, and subcode data is recorded on a segment basis in a track without being randomized.

At this time, an encryption code is recorded in the subcode portion of the tape to confirm whether or not to reproduce it, and then decides whether or not to reproduce it.

In addition, a cryptographic key was added to the set to prevent unauthorized copying by the general public.

The magnetic recording / reproducing apparatus according to the related art gives a cryptographic key to a set so that a third party can not illegally reproduce a program recorded by the user, or records a cryptographic code in a part of the tape to confirm it at the time of reproduction, This is because it is possible to prevent unauthorized copying in this set, but unauthorized viewing in another set can not be prevented.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a magnetic recording and / or reproducing apparatus capable of encrypting and recording a program recorded by a user, And a magnetic recording / reproducing apparatus using a user code for preventing unauthorized viewing of a recorded program.

Another object of the present invention is to provide a control method corresponding to the apparatus.

1 is a block diagram showing a recording / reproducing apparatus of a general digital VCR

2 is a diagram showing a format of a track and a frame of a general digital VCR;

3 is a diagram showing a recording format of an A / V signal and an additional signal of a digital VCR according to the prior art

4 is a block diagram showing a recording / reproducing apparatus of a digital VCR using a user code according to the present invention

5 is a diagram showing a recording / reproducing format of data recorded / reproduced using a user code according to the present invention

6 is a flowchart illustrating a data recording method using a user code according to the present invention.

7 is a flowchart illustrating a method of reproducing data using a user code according to the present invention.

Description of the Related Art [0002]

20: input / output unit 21: shuffle /

22: compression and decompression unit 23: audio signal processing unit

24: Formatting unit 25:

26: demodulation block 27:

A magnetic recording / reproducing apparatus and a control method thereof using a user code according to the present invention are characterized in that formatting means adapted to a format for recording compressed data on a tape records the data in a normal first recording format, In a second recording format in which an arbitrary user's password code is assigned.

Another aspect of the present invention is to randomly vary a track recording order in which data of one frame is shuffled and divided into a plurality of tracks for recording in the second recording format.

In another aspect of the present invention, when the recorded data is reproduced, the user code given by the user at the time of recording is compared with the user code inputted at the time of reproduction, and if they match, .

Hereinafter, a user code according to the present invention will be described with reference to the accompanying drawings.

FIG. 4 is a block diagram illustrating a recording / reproducing apparatus of a design VCR using a user code according to the present invention, FIG. 5 is a diagram illustrating a recording / reproducing format of data recorded / reproduced using a user code according to the present invention to be.

Referring to FIG. 4, an analog audio / video signal input / output unit 20 converts an analog audio / video signal to a digital signal and inputs / outputs the analog audio / video signal. A shuffle and deshuffle unit 21 for shuffling the converted digital video signal and deshuffling the reproduced digital video signal; An audio signal processor 23 for processing an audio signal applied through the input / output unit 20 and an audio signal during reproduction; A compression and expansion section (22) for compressing a signal shuffled at the shuffle and doughshuff section (21) and for extending the reproduction signal upon reproduction; A formatting unit (24) for formatting the compressed digital data according to the recording format of the tape and for formatting the user code into a second recording format upon input and de-formatting the user code upon reproduction; A control unit 25 for receiving a user code inputted by a user and controlling the format unit 24 to format the data into a new second recording format and controlling the demodulation according to the original track order during reproduction; A modulation / demodulation unit 26 for modulating data formatted in the format unit 24 and demodulating the data formatted in reproduction, and a recording / reproducing unit 27 for recording and reproducing the modulated data.

The analog video signal inputted through the input / output unit 20 is converted into a digital video signal and input to the shuffle and dessuffler unit 21.

In the shuffle and deshuffle unit 21, the converted video signal is shuffled and then applied to the compression and expansion unit 24.

The compression and decompression unit 22 compresses the video signal through DCT, VLC, and the like, and then adds an error correction code (ECC) for error correction.

Further, after the recording coding for recording is performed, the data is applied to the formatting unit 24.

The formatting unit 24 formats the compressed digital data into a recording format so that the compressed digital data can be recorded on the tape of the recording unit 27. [

At this time, if the user inputs a user code through the control unit 25 to prevent unauthorized viewing by a third party, as shown in FIG. 5, And records the data on the tape of the recording / reproducing section 27 through the modem section 26. [

When the digital data recorded in the recording / reproducing unit is reproduced, the demodulating unit 26 demodulates the digital data, and then supplies the demodulated data to the format unit 24.

Here, when the user does not input the user code at the time of reproduction, the second recording format format, that is, the format of the randomly recorded format is displayed on the image display device.

However, when the image is displayed in the random recording format as described above, the original image is not properly displayed on the screen because the image is displayed in a state of being mixed with the original image.

When the user inputs the user code and compares the recorded user code with the user code inputted at the time of reproduction, the data is reformatted in the order of the original track number.

5, the digital data de-formatted in the format unit 24 when reproducing the randomly recorded digital data are compressed and stretched in the order of the original track number according to one control signal of the control unit 25 22).

The compression and expansion unit 22 decompresses the de-formatted digital data, adds the error correction code, and deshuffles the compressed data to the shuffle and shuffle unit 21 and displays the data on the image display unit through the input / output unit 20 will be.

The magnetic recording and reproducing operation using the user code will be described in detail with reference to FIGS. 6 and 7. FIG.

FIG. 6 is an operation flow chart illustrating a data recording method using a user code according to the present invention, and FIG. 7 is an operation flowchart showing a data reproducing method using a user code according to the present invention.

First, referring to FIG. 6, when the digital data compressed by the compression / decompression unit 22 is recorded on a tape, the user enters a user code (S101) Is transmitted in addition to the error correction code according to one control signal of the control unit 25 (S102).

If the user code is given, the control unit 25 randomly formats the track number and the user code information in one frame in accordance with one control signal of the control unit 25, And converted into a code suitable for recording in a maker code pack (S103).

The user code and the one-frame data converted into the appropriate code are recorded in respective tracks according to one control signal of the control unit 25 (S104).

On the other hand, the user code is not input (S101), and the video and audio data are normally recorded in the same track as the conventional recording method (S105).

Referring to FIG. 7, the operation of reproducing the recorded data is as follows. A tape is inserted into a set and it is determined whether a user code is input (S201).

If the user code is input, the user code is assigned to the error correction code ECC (S202).

Then, the control unit 25 determines whether the user code is identical to the user code recorded in the sub code unit of the tape at the time of data recording (S203).

At this time, if the user code inputted at the time of reproduction is the same as the user code inputted at the time of recording, the formatting section 24 performs de-formatting in accordance with one control signal of the control section 25 in accordance with the order of the original track number in one frame S204).

When de-formatting is completed, the de-formatted digital data is decompressed in the compression and decompression unit 22 and the decompressed data is deshuffled in the shuffle and deshuffle unit 21.

The deshuffled digital signal is again converted into an analog signal and displayed on the image display device through the input / output unit 20 (S205).

However, if the user code is not input, formatting is performed in the format unit 24 in a conventional manner (S206). At this time, since data is randomly recorded at the time of recording, a proper image can not be displayed at the time of reproduction will be.

The magnetic recording / reproducing apparatus and the control method using the user code according to the present invention can perform scrambling without loss of original data only by operation of very simple data. If the user code at the time of recording is unknown, Which is inevitable for high-density recording, unlike the analog method, there is an advantage that it is very easy to use in a DVCR that records one frame of data over several tracks.

In addition, when the DVCR is used as a data storage, there is an advantage that it can be usefully used for storing and managing data by a password, that is, a user code.

Claims (7)

In the magnetic recording / reproducing apparatus, Formatting means for formatting the compressed digital audio / video data to be input according to a recording format of the tape according to a format control signal and formatting the compressed digital audio / video data into a second recording format according to another format control signal when the user code is input; Recording means for recording the formatted data according to a recording control signal; And a control unit for providing the format control signal and the one recording control signal. The method according to claim 1, Wherein the original track recording order is randomly changed and recorded in recording in the recording means in the first and second recording formats. In the magnetic recording / reproducing apparatus, Reproducing means for reproducing randomly recorded user code data and video / audio data when a user code is input; Formatting means for de-formatting the reproduced data according to an original format number sequence in a frame on a frame-by-frame basis according to a format control signal; And control means for providing the de-format control signal and displaying the de-formatted data. In the magnetic recording and reproducing apparatus, An input / output unit for converting input analog audio / video signals into digital signals and inputting / outputting the digital audio / video signals; A shuffle and a deshuffle unit for shuffling the converted digital video signal and deshuffling the reproduced digital video signal; An audio signal processing unit for processing an audio signal applied through the input / output unit and an audio signal during reproduction; A compression and expansion unit for compressing a signal shuffled at the shuffle and the diplexer unit and for expanding the signal at the time of reproduction; A formatting unit configured to format the compressed digital data according to a recording format of the tape, to format the user code into a second recording format upon input and to de-format the user code upon playback; A control unit which receives a user code inputted by a user and controls the format unit to be formatted into a new second recording format and controls de formatting according to the original track order during reproduction; A modulation / demodulation unit for modulating data formatted in the format unit and demodulating the data formatted in reproduction, and a recording / reproducing unit for recording and reproducing the modulated data. 5. The method of claim 4, Wherein the original track recording order is randomly converted and recorded in recording in the recording means in the second recording format. In the magnetic recording / reproducing method, Determining whether a user code is input; If the user code is input as a result of the determination, formatting the recording medium in a single recording format in units of one frame at random according to one control signal; Changing the input user code according to a control signal with another code capable of recording the user code; And recording the video / audio data of one frame and the converted user code. In the magnetic recording / reproducing method, Determining whether a user code is input when randomly recording data is reproduced; Comparing the flagged user code with the user code input during playback according to the determination result; Deformatting according to one control signal in accordance with an order of the original track number in one frame according to the comparison result; And displaying the de-formatted data on an audio / video signal processor according to a control signal.