KR100220911B1 - Method and apparatus for recovering the scrambling screen of a cable television broadcasting system - Google Patents

Abstract

The present invention relates to a method of releasing a picture of a CATV terminal in a cable TV broadcasting, and in particular, a first process of setting a type of picture for each channel; A second step of storing, in the storage means of the subscriber station, the secret release information for each channel according to the secretion format set in the first step; A third step of transmitting a video signal to be transmitted from a cable TV station to each channel according to the secretion format set in the first step; And a fourth process of releasing a video signal received by selecting a channel at the subscriber station according to the releasing information for each channel stored in a second process. By providing a restoration method and a system therefor, it is possible to restore the screen of the secretion state without the need for data communication for a large amount of release information associated with the secretion at the headend.

Description

Method for canceling / restoring a secret screen in a cable TV broadcasting system and a device thereof

1 is an exemplary network configuration of a conventional CATV system.

2 is an exemplary network configuration of a CATV system according to the present invention.

3 is a block diagram of a smart card according to the present invention.

* Explanation of symbols for main parts of the drawings

HE: Headend 10: Firearm

20: channel modulator 30A: secretion control unit

100 A 100N: subscriber station 110A: tuner

120A: Detector 170A: Memory

160A: spark release control unit 150A: spark clearer

171: interface logic 172: ROM

173: password comparison unit 174: memory control unit

Clearing the secret screen of the CATV terminal by storing the secret information of the headend in a memory means provided in the subscriber terminal in advance, and allowing the viewer to access the information stored during the tuning of the secret broadcast channel and simply cancel the secret without communication between the headend and the terminal. A method and apparatus therefor.

In general, in the conventional wired TV broadcasting, the secretion release information is transmitted through communication from the headend (broadcasting station) to the terminal (converter) through the communication, and with reference to the attached FIG. 1 as follows.

1 is a diagram illustrating an example of a network configuration of a conventional CATV system, and includes a head-end (HE) and a subscriber station (100A). 100N) side.

Looking at the configuration of the head end (HE), and receives the video signal (baseband signal) before being modulated and mixed according to the secretion control signal, and the broadcast channel to the signal secreted by the talker 10 A channel modulator 20 for modulating with a frequency, and inputting a secreting control signal to the sparking machine 10, and subsequently transmitting the channel to the subscriber station 100A. The non-clearing control unit 30 for generating and outputting a non-clearing control signal for recovery on the 100N side, and the non-clearing signal output from the non-clearing control unit 30 in a frequency other than a broadcast channel frequency (for example, an outband frequency). Frequency modulated modem 40 to modulate), and combine 50 which combines two signals outputted from frequency modulated modem 40 and channel modulator 20 and puts them on one line.

Subscriber terminal (100A) corresponding to the head end (HE) configured as described above Each configuration includes a tuner 110A that tunes a broadcast channel frequency to an intermediate frequency, a detector 120A that demodulates a video signal at an intermediate frequency output from the tuner 110A, and an outband frequency. Deactivation control unit (140A) for receiving the frequency demodulation modem (130A) for receiving and deciphering the deactivation information, and generating a release control signal for receiving the deactivation information evicted from the frequency demodulation modem (130A) to control the de-ciphering And a decryption decompressor 150A which decodes the demodulated video signal output from the detector 120A according to the release control signal outputted from the deactivation control unit 140A and outputs the decoded video signal to a TV or a VCR.

Looking at the network operation process of the conventional CATV system configured as described above, demodulating the video signal received from the program supplier using satellite or optical media or from the system operator's own video player (VCR, VDP, etc.) To generate and enter into the firearm (10).

The video signal receiver 10 receives the video signal and inverts the video signal based on the horizontal synchronization signal for each TV screen scan line according to the video signal control signal from the video controller 30. Invert it.

The video signal thus secreted is modulated by the channel modulator 20 to the CATV broadcasting channel frequency, and the secretion control unit 30 transmits information necessary for clearing the speech corresponding to the secret information generated by the channel modulator 20 to the frequency modulation modem 40. Enter it.

The frequency modulation modem 40 modulates the information related to the secretion to the combine 50 after FSK modulation to a frequency (out band) rather than the CATV broadcasting frequency band, and in the combine 50, the frequency modulation modem 40 The signal output from the signal and the signal output from the channel modulator 20 are mixed and transmitted to each subscriber station using a cable broadcasting line.

The signal corresponding to the CATV broadcasting channel among the mixed signals is tuned by the tuner 110A and demodulated as a video signal by the detector 120A. At this time, the video signal is a secreted signal, which is a signal state that the viewer cannot watch even through a TV or a VCR.

Therefore, the frequency demodulation modem 130A receives the demodulation cancellation information modulated to the outband frequency to demodulate the signal, and demodulates it. The clearing information output from the frequency demodulation modem 130A is transmitted to the clearing control unit 140A, and the clearing control unit 140A generates a release control signal for controlling the clearing unlocker 150A.

The deactivator 150A restores the deactivation state of the video signal demodulated by the detector 120A according to the input release control signal, and outputs the reconstructed video signal so that the CATV broadcasting subscriber can watch it on a TV or a VCR.

In the conventional CATV system, the secreting and releasing method is a line by line video inversion method. Non-inverting method.

By operating such a scheme, the data for the secret key (PN-KEY), which enables the viewer to make the screen impossible to view without the converter and to release the secreted secret screen, is sent to the subscriber terminal through the headend's secret control unit and modem. It is possible to release the secretion screen by transmitting it, but the problem that occurs in the actual field has to go through numerous paths such as wire network of several kilometers from head end to converter, various network amplifiers, taps, etc. As a result of the frequent damage or loss, the converter has a problem that it is often impossible to watch because the converter can not be released.

An object of the present invention for solving the above problems is to record the deactivation information of the headend in a smart card in advance so that the deactivation can be performed by simply inserting the smart card into the converter when the viewer watches the CATV broadcast. The present invention provides a method and apparatus for releasing a secret screen of a CATV terminal to easily cancel a secret without communication between terminals.

A feature of the present invention for achieving the above object is, in the method for releasing / restoring a picture screen of a cable TV broadcasting system, a first process of setting a type of a password for each channel, and each according to the type of password set in the first process A second process of storing the secretion release information for each channel in a storage means of the subscriber terminal, a third process of secreting and transmitting the video signal to be transmitted from the cable TV station side by channel according to the secretion format set in the first process; And a fourth process of de-secreting the video signal received by selecting a channel at the subscriber station according to the channel-releasing information for each channel stored in the second process.

According to another aspect of the present invention for achieving the above object, in the method for releasing / restoring a picture screen of a cable TV broadcasting system, a first process of setting specific codes of a predetermined bit and each specific code set in the first process A second step of setting a separate talk format; a third step of storing the talk release information according to the talk format set in the above procedure in a storage means of the subscriber terminal based on a specific code corresponding thereto; A fourth step of slicing a desired video signal according to the scrambled format set in the second procedure and modulating and transmitting a specific code corresponding to the scrambled format together with the video signal; When detecting a video signal, the specific code included in the mixed video is detected and the code stored in the third process It is to include a fifth step of ciphering according to the screen information released off.

Another aspect of the present invention for achieving the above object, in the cable TV broadcasting system;

Inputting a control signal according to a specific form of a pattern for visualizing a picture signal, a channel modulator for modulating the signal signaled by the talker to a broadcast channel frequency, and inputting a control signal according to a pattern for screen vision to the picture signal A cable TV broadcasting station including a secretion control unit to make a sound;

A tuner that tunes a broadcast channel frequency to an intermediate frequency, a detector that demodulates a video signal at an intermediate frequency output from the tuner, and non-deactivation information for restoring a picture that has been ignited according to a specific pattern of patterns. A deactivation control unit for generating a release control signal to release the secretion according to the deactivation information accessed from the memory, and a demodulated video signal output from the detector according to the release control signal output from the deactivation control unit The present invention provides a plurality of subscriber stations including a deactivator for restoring the TV or the VCR.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

2 is an exemplary network configuration of the CATV system according to the present invention. As shown in the related art, the headend HE and the subscriber station 100A are largely similar to the conventional art. 100N) side.

Looking at the configuration of the head end (HE), and receives the video signal (baseband signal) before being modulated and mixed according to the secretion control signal, and the broadcast channel to the signal secreted by the talker 10 A channel modulator 20 for modulating with a frequency, and a sparking control section 30A for inputting a control signal to the talker 10 according to a pattern of a specific form for screen blanking.

Subscriber terminal (100A) corresponding to the head end (HE) configured as described above Each configuration of the 100N side includes a tuner 110A for tuning a broadcast channel frequency to an intermediate frequency, a detector 120A for demodulating a video signal at an intermediate frequency output from the tuner 110A, and a specific form. A memory 170A in which the decryption information for restoring the screen imaged according to the pattern is stored, and a secretion control unit for generating a release control signal so that the secretion is released in accordance with the decryption information accessed from the memory 170A. 160A) and a deactivator 150A that de-encodes the demodulated video signal output from the detector 120A according to the release control signal output from the deactivation control unit 160A and outputs the de-decoded video signal to a TV or a VCR. .

The memory of the configuration may use a smart card, the configuration of the smart card when using the smart card, as shown in the attached Figure 3, the interface logic for interfacing with the deactivation control unit 160A (171) And a ROM 172 which stores deactivation information for restoring a descrambled screen according to a pattern of a specific form, and a password granted to a legitimate user among data flowing through the interface logic 171 is inputted. The interface logic 171 stores data stored in the ROM 172 according to a password comparison unit 173 for determining a value and a control signal determined to be the same as a password stored in the password comparison unit 173. The memory controller 174 transmits the decryption control unit 160A to the control unit 160A.

Looking at the operation of the CATV system according to the present invention configured as described above are as follows.

The talker 10 receives the information necessary for the sparking from the sparking control unit 30A and inverts / non-inverts the incoming baseband video signal for each horizontal synchronization signal. The secreted signal is modulated by the channel modulator 20 into a CATV broadcast channel and sent to each subscriber station using a CATV transmission line (cable or the like).

On the other hand, the clearing information (4 bytes) for restoring the screen to be burned is specialized according to a predetermined pattern predetermined for each CATV broadcasting channel so that the information is stored in the memory (smart card) in the converter or terminal of each subscriber. It is stored as shown in Table 1.

Accordingly, when the viewer turns on the converter and selects a channel, the deactivation information (4 bytes) a for the tuned channel is deactivated in the deactivation control unit 160A so that the viewer can release the deactivation screen for the corresponding channel. 170A) is accessed and read out, and outputted to the decanter 150A to restore the decoded video signal detected (demodulated) by the tuner 110A and the detector 120A.

Another embodiment different from the above-described embodiment is as follows.

In addition, if the above-described method of the present invention was a method of pre-commiting the secret release information so that the channel-specific secretion screen can be released in CATV broadcasting, in another embodiment according to the present invention described below, the secretion of a specific pattern for each channel It is a method of storing secret information according to specific code without setting a form.

That is, it has a data storage method as shown in Table 2 below,

The deactivation code according to the deactivation pattern in the video vertical synchronization section is stored, and the previously deactivated deactivation information corresponding to the deactivation code is stored as shown in Table 2 above.

Then, when the secretion control unit 30A, which generates a secretion control signal to generate a secretion among the headends, generates a signal for secretion control in the secretary 10, a specific code according to the secretion form is generated. It can be loaded on the vertical synchronization signal.

Accordingly, unlike the first embodiment of the present invention described above, the signal output from the headend is a complex secret control signal including not only secret information but also secret ID.

The deactivation ID is modulated together with other video signals by the channel modulator 20 to be sent to the subscriber station, and the deactivator 150A transmits a specific code carried in vertical synchronization to the deactivation control unit 160A.

The deactivation control unit 160A controls the deactivation operation of the deactivator 150A by accessing corresponding deactivation information from the memory 170A based on a specific code input.

In the second embodiment according to the present invention has an advantage that does not have in the first embodiment, looking at the example,

In the first embodiment, it is difficult to cope with the city office because it is impossible to change the predetermined channel secret information. In the second embodiment, the headend selects the secret ID in real time from among a large number of secret IDs pre-contracted by the secret control unit. In addition, there is an advantage that can be changed to remove concerns about the city office.

According to the first and second embodiments according to the present invention as described above, if the user makes a conversation at the headend, the screen of the corresponding secretion state can be restored even without a considerable amount of data communication.

In addition, since there is no communication for deactivation in the CATV system, the configuration of the CATV system is simplified and economical.

In addition, the application of the second embodiment, in addition to the above-described advantages, the effect that can be prevented the city office is additionally generated.

Claims (5)

Claims [1] A method of releasing / restoring a picture screen of a cable TV broadcasting system, the method comprising: a first step of setting a picture type for each channel; A second step of storing, in the storage means of the subscriber station, the secret release information for each channel according to the secretion format set in the first step; A third step of transmitting a video signal to be transmitted from a cable TV station to each channel according to the secretion format set in the first step; And a fourth process of releasing a video signal received by selecting a channel at the subscriber station according to the releasing information for each channel stored in a second process. How to restore. A method of canceling / restoring a non-picture screen of a cable TV broadcasting system, the method comprising: a first step of setting specific codes of a predetermined bit; A second process of setting a separate secret form for each specific code set in the first process; A third step of storing the clearing release information according to the set secret type in the step in the storage means of the subscriber station based on the specific code corresponding thereto; A fourth step of sequencing the video signal to be transmitted by the cable TV broadcasting station according to the secret format set in the second process and modulating and transmitting a specific code corresponding to the secret format together with the video signal; And a fifth step of detecting a specific code included in the mixed image when detecting a video signal received by selecting a channel in the subscriber station and de-arming according to the code release information for each code stored in the third step. Secret screen release / restore method of the cable TV broadcasting system comprising a. In a cable TV broadcasting system, a signal generator for receiving a video signal and mixing the video signal according to a secret control signal, a channel modulator for modulating the signal secreted by the apparatus into a broadcast channel frequency, and a specific form for screen secreting the apparatus A cable TV broadcasting station including a secretion control unit for inputting a control signal according to a pattern; A tuner that tunes a broadcast channel frequency to an intermediate frequency, a detector that demodulates a video signal at an intermediate frequency output from the tuner, and non-deactivation information for restoring a picture that has been ignited according to a specific pattern of patterns. A deactivation control unit for generating a release control signal so as to release the secretion according to the deactivation information accessed from the memory, and a demodulated video signal output from the detector according to the release control signal output from the deactivation control unit; And a plurality of subscriber stations including a deactivator for restoring and outputting them to a TV or a VCR. 4. The cable TV broadcasting system according to claim 3, wherein the memory uses a smart card. The smart card of claim 3, wherein the smart card comprises: interface logic for interfacing with the decryption control unit; A ROM for storing decryption information for restoring a screen image according to a pattern of a specific form; A password comparison unit that determines whether a password granted to a legitimate user is input among the data flowing through the interface logic; And a memory controller configured to transfer the data stored in the ROM to the decryption controller through the interface logic according to a control signal determined that the password inputted from the password comparator is the same as the stored password. TV broadcasting system.