JPH04183189A - Charged caption broadcasting sending/receiving unit - Google Patents

Abstract

PURPOSE:To enable only a contractor to obtaing relevant caption information by including a character multiprogram number about caption information in associated information. CONSTITUTION:First, in a sending side unit 1, a program number of caption information 35 is included in associated information 9, and a character multisignal coding section 36 converts this caption information to character multisignal format. This character multisignal 38 is superimposed on a vertical retrace line period of a video signal scrambled by a superimposer 39. Accordingly, a non-contractor cannot normally select caption information. At the receiving side, separation section 40 separates a character multiple signal. Further, associated information 21 that was separated by a separation section 19 is decoded by a decoding section 22, and treated by a contract condition compare section 26 for contract condition, and if the contract condition, matches with a predetermined condition, a program number of caption information 35 can be obtained from associated information, and by controlling a program number selecting section 44 using a program number signal 52, in a character multisignal decoding section 43, caption information is decoded, thereby being able to obtain a caption information signal 49.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a pay subtitle broadcast transmitting/receiving apparatus for pay television broadcast.

2. Description of the Related Art In recent years, satellite broadcasting has gained momentum, and paid broadcasting using satellites is about to become practical.

An example of the conventional pay subtitle broadcasting transmitting and receiving apparatus described above will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of a conventional paid subtitle broadcast transmitting and receiving device. In FIG. 2, 1 is a television signal transmitting device. 2 is a video signal. 3 is a video scrambler that scrambles the video signal 2; 4 is an audio signal. 5 is an audio signal scrambler that scrambles the audio signal 4; 6 is a pseudo random number generator. 7 is a pseudo-random number sequence generated by the pseudo-random number generator 6,
This is a pseudo-random number sequence for audio that scrambles the audio signal 4. 8 is a pseudo-random number sequence generated by the pseudo-random number generator 6,
This is a video pseudo-random number sequence for scrambling the video signal 2. 9 is related information for obtaining the original video signal and the original audio signal on the receiving side. 10 is an encryption unit that encrypts the related information 9. 11 is encrypted related information. 12 is key information for encrypting the related information 9. 13 is an audio signal scrambled by the audio scrambler 5. 14 is a video signal scrambled by the video scrambler 3. 15 is a multiplexing unit that multiplexes the scrambled audio signal 13 and the encrypted related information 11 onto a transmission path. 16 is a multiplexed audio signal and related information. 17 is a transmission line. , 35 is subtitle information. 36 is a character multiplex signal encoding unit that encodes the subtitle information 35 into a character multiplex signal format. 37 is a program number control for setting and controlling a program number in character multiplexing of the subtitle information 35. 38 is a character multiplex signal. 39 is the scrambled video signal 14
This is a superimposition device that superimposes a character multiplex signal 38 on the character multiplex signal 38.

18 is a television signal receiving device. 40 is a signal separation unit that separates the video signal and the character multiplex signal. 4
1 is a scrambled video signal separated by the signal separation unit 40. 42 is a character multiplex signal separated by the signal separation unit 40. Reference numeral 19 denotes a separation unit that separates the multiplexed audio signal and related information. 20 is a separated audio signal. 21 is separated related information.

22 is a decoding unit that decodes the separated related information 21; 23 is key information for decryption by the decryption unit 22. 24 is information corresponding to contract conditions among the decoded related information. 25 is initial value information of the pseudo random number generator among the decoded related information. 26 is a contract condition comparison unit that compares whether the contract conditions of the receiving device 18 match the received contract conditions. 27 is a pseudo-random number generator side door signal that controls the pseudo-random number generator PIII as a result of the comparison of contract conditions. 28 is a pseudo random number generator. 2
9 is a pseudo-random number sequence for audio among the pseudo-f random number sequences generated by the pseudo-random number generator 28. 30 is pseudo random number generator 2
This is a pseudo-random number sequence for video among the pseudo-random number sequences generated in step 8. 31 is an audio descrambler that descrambles the received audio signal.

32 is a video descrambler that descrambles the received video signal. 33 is a descrambled video signal, which is equal to the original video signal 2; 34 is a descrambled audio signal, which is equal to the original audio signal 4; 43 is
This is a decoding unit for character multiplexed signals.

44 is a program selection unit that selects a text multiplex program. 45 is a program selection signal. 47 is a signal indicating the program attributes of the selected multiplex text program.

Reference numeral 46 denotes a screen control unit that controls switching of the screen and superimposition of text information in accordance with the program attribute signal 47. The 4th is a screen control signal. 49 is subtitle information. Reference numeral 50 denotes a switching unit that controls switching between the descrambled video signal 33 and the subtitle information 49 using the screen control signal 48. 51 is a video signal on which subtitle information is superimposed on the screen.

The operation of the pay subtitle broadcast transmitting/receiving device configured as described above will be described below.

In paid broadcasting, only those who have a legitimate reception contract can properly receive the program, and non-subscribers cannot receive the program correctly. In order to simulate this, it is necessary to scramble the video signal 2 and the audio signal 4 in the transmitting device 1 and to descramble them in the receiving device 18. To descramble, information for that purpose is required, and this information is related information 9. The related information 9 includes the initial value of the 1f (U random number generator 6) and the contract conditions. The random number sequence is divided into an audio 7 and a video 6. The audio scrambler 5 uses a scrambling method that converts the audio signal 4 into PCM data and then adds the audio pseudorandom number 7 to the PCM data. For video, the video scrambler 3 converts the original video signal 2 into digital data, and then uses the video pseudorandom number sequence 8 to perform, for example, an intra-scan line signal switching method or a scan line that changes the order of the scan lines. The related information 9 is transmitted to the receiving side so that the scrambled video signal 14 and the scrambled audio signal 13 can be descrambled in the receiving side device 18. It is encrypted in the encryption unit 10 of the sending device 1 so that non-subscribers cannot know it.Key information 12 is used as a key for this encryption.The encrypted related information 9 is scrambled. The multiplexed signal 16 is multiplexed with the audio signal 13 and sent to the transmission line 17 as a multiplexed signal 16.

On the receiving side 18, a separator 19 separates the scrambled audio signal 20 and the encrypted related information 21 from the multiplexed signal 16. Separated related information 2
1 is decrypted in the decryption unit 22 using the same key information 23 as the key information 12 of the sending device 1. Among the decoded related information, an initial value 25 for the pseudo random number generator 284 is set. Also,
Among the decrypted related information, the contract conditions are sent to the contract condition comparison section 26, where they are compared to see if they match the contract conditions of the receiving device 18. The pseudo-random number generator control signal 27 controls the pseudo-random number generator 2 to operate normally if it is determined that the user is a subscriber based on the result of this comparison, and if it is determined that the user is a non-contractor, The pseudo random number generator 28 is controlled so as not to operate normally. In the case of a subscriber, a correct pseudo-random number sequence is generated from the pseudo-random number generator 28, and this is divided into an audio pseudo-random number sequence 29 and a video pseudo-random number sequence 30. The audio descrambler 31 obtains the original PCM audio data by adding the audio pseudo-random number sequence 29 to the scrambled audio signal 20, and converts it into an analog signal, which is the same as the original audio signal 2. Audio signal 3
4 is obtained. The video descrambler 32 performs descrambling processing using the video pseudorandom number sequence 30 to obtain a video signal 33 that is the same as the original video signal 2.

Furthermore, in free-to-air broadcasting, subtitle broadcasting services for the hearing-impaired may be considered, similar to conventional broadcasting. In that case, in the transmitting device 1, the subtitle information 35 is encoded as a text multiplex program in the text multiplex signal encoding unit 36, and after the program number control unit 37 assigns an appropriate program number, the subtitle information 35 is encoded as a text multiplex program. Another method is to use a superimposer 39 to superimpose the signal on the vertical retrace period of the video signal. Receiving side device 18
Now, from the character multiplex signal 42 separated by the separation unit 40,
The program selected by the program selection section 44 is decoded by the character multiplex signal decoding section 43 to obtain subtitle information 49. If the selected text information program is subtitle information, a signal 4 indicating its attribute
7, the screen control unit 46 generates a screen control signal 48 in order to superimpose the subtitle information on the original screen, and the switch 50 superimposes the subtitle information 49 on the descrambled video signal 33.

Problem to be Solved by the Invention However, with the above configuration, there is no relationship between the scrambled video and audio signals and the subtitle information program, so even non-subscribers can only watch the subtitle information program. I have a problem.

In view of the above problems, the present invention provides a pay subtitle broadcast transmitting/receiving device that allows only pay broadcast subscribers to obtain subtitle information of their contracted programs.

Means for Solving the Problems In order to solve the above problems, the pay subtitle broadcast transmitting/receiving device of the present invention includes a scrambling means for scrambling the video signal and a related information encoder for encrypting the related information on the television video signal transmission side. a multiplexing means for multiplexing the encrypted related information onto a transmission path; a text multiplexing signal encoding means for encoding the subtitle information into a text multiplex signal; A program number control means for assigning to a program number, a means for superimposing a character multiplexed signal on a video signal, and on the receiving side, a means for descrambling the video signal, a separating means for separating related information from the received signal, and an encryption method. a related information decoding means for decoding the related information, a contract condition comparing means for comparing whether the content of the related information matches the contract conditions, a text multiplex signal separating section, and a text multiplex signal decoder. a program selection unit that selects a program for a text multiplex program based on a program number of subtitle information obtained when contract conditions match; a screen control unit that performs screen control for the text multiplex program;
The apparatus is equipped with a switching means for switching between a video signal and subtitle information.

Effect of the present invention With the above-described configuration, the text multiplex program number of subtitle information is included in the related information, and on the receiving side, only the subscriber can obtain the subtitle information.

Embodiment Hereinafter, a paid subtitle broadcast transmitting and receiving apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a pay subtitle broadcast transmitting and receiving apparatus in an embodiment of the present invention. In the figure, sending device 1
In the related information 9, the program number of the subtitle information 35 is included. Further, in the receiving side device 18, 52 is a program number signal indicating the program number of the subtitle information 35 extracted from the contract condition comparing section 26.

The operation of the pay subtitle broadcast transmitting/receiving apparatus configured as described above will be explained below using FIG. 1.

First, in the sending device 1, subtitle information 3 is added to the related information 9.
Include program number 5. Normally, the related information is updated to change the scramble state every about 1 second and to increase the degree of confidentiality. At this time, the program number of the subtitle information 35 is also changed each time. Then, the character multiplex signal encoder 3
In step 6, this subtitle information is encoded into a text multiplex signal format. This character multiplex signal 38 is superimposed on the vertical blanking period of the scrambled video signal in a superimposer 39.

By doing so, non-subscribers will not be able to correctly select subtitle information.

On the receiving side, a separating section 40 separates the character multiplexed signal. Further, the related information 21 separated by the separating unit 19 is decoded by the decoding unit 22, and then the program number of the subtitle information 35 is determined by the contract condition comparison unit 26 if the contract conditions match. is obtained from the related information, and the program number signal 52 controls the program selection section 44, so that the subtitle information is decoded in the character multiplex signal decoding section 434, and the subtitle information signal 49 is obtained. The screen control unit 46 generates a screen control signal 48 for superimposing subtitle information 49 on the descrambled video signal 33 on the screen, and controls the switch 50.

As described above, according to this embodiment, on the television video signal transmitting side, there is a scrambling means for scrambling the video signal, a relevant information encrypting means for encrypting the relevant information, and a transmission path for transmitting the encrypted relevant information. a character multiplex signal encoding means for encoding subtitle information into a character multiplex signal; a program number control means for allocating the subtitle information to a program number included in the related information; On the receiving side, a means for descrambling the video signal, a separating means for separating the related information from the received signal, and a related information decoding means for decoding the encrypted related information. a contract condition comparing means for comparing whether the contents of the related information match the contract conditions, a character multiplex signal separation unit, a character multiplex signal decoding unit, and a character multiplex signal decoding unit, which is obtained when the contract conditions match. a program selection unit that selects a text multiplex program based on a program number of subtitle information; a screen control unit that performs screen control of the text multiplex program;
By providing a switching means for switching between the video signal and the subtitle information, only the subscriber can view the subtitle information of the program to which he or she has subscribed.

Effects of the Invention As described above, the present invention provides, on the transmission side, a scrambling means for scrambling a video signal, a related information encryption means, a multiplexing means for multiplexing the encrypted related information on a transmission path, and a subtitle. A character multiplex signal encoding means for encoding information into a character multiplex signal, a program number control means for allocating subtitle information to a program number included in the related information, and a means for superimposing the character multiplex signal onto a video signal are provided. , on the receiving side,
a video signal descrambling means, a separation means for separating related information from a received signal, a related information decoding means for decoding the encrypted related information, a contract condition comparison means,
By providing a text multiplex signal separation section, a text multiplex signal decoding section, a program selection section, a screen control section for controlling the screen of the text multiplex program, and a switching means for switching between the video signal and subtitle information. , only subscribers can view subtitle information for programs they have subscribed to.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a pay subtitle broadcast transmitting/receiving apparatus according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional pay subtitle broadcast transmitting/receiving apparatus. 3... Video scrambler, 9... Related information, 10... Encryption unit, 15... Multiplexing unit, 19... Separation unit, 22...Decoding unit, 26...Contract condition comparison unit, 32...
...Video descrambling unit, 36...Character multiplex signal encoding unit, 37...Program number control unit, 3
9...Superimposition part, 40...Separation part, 43
...Character multiplex signal decoding section, 44...
Program number selection section, 46...Screen control section, 50.
...switcher. Name of agent: Patent attorney Akira Okaji and 2 others-t
East; r

Claims (1)

[Claims] On the television video signal transmission side, a scrambling means for scrambling the video signal, a related information encrypting means for encrypting the related information, and a multiplexing device for multiplexing the encrypted related information onto a transmission path. a text multiplex signal encoding means for encoding subtitle information into a text multiplex signal; a superimposing means for superimposing the text multiplex signal on the scrambled video signal; and a program number control means for controlling the number, and on the receiving side, a video signal descrambling means, a separation means for separating related information from the received signal, and a related information decoding means for decoding the encrypted related information. a contract condition comparison means for comparing whether the content of the related information matches the contract conditions; a means for decoding a text multiplex signal; a text multiplex program selection means; and a text multiplex program selection means. A pay subtitle broadcast transmitting/receiving device comprising: a screen control means for controlling a screen according to the content; and a signal switching means for switching between a descrambled video signal and a text multiplex screen.