JPS60199288A - Broadcasting system - Google Patents

Abstract

PURPOSE:To render a person who does not pay a charge to know some part of broadcast contents by performing selectively an action of a cipher machine, by ciphering either a video or a sound and by the person, who does not pay a charge, outputting information of non-ciphered part. CONSTITUTION:In case of ciphering only a video signal, a transmission side 31 ciphers a video signal 20 with aid of the prescribed cipher key 23 by means of a cipher device 22, while non-ciphered sound signal 21 is multiplexed and transmitted by a multiplex circuit 24. A receiving side 32 separates a video and a sound by a separator circuit 30. The sound signal is properly outputted by an output part 27, while the video signal can be decoded by only the audience who will pay a receiving fee and has a decoding key 29. This decoding is carried out by a decoder 28 with aid of the key 29, and its output is properly performed to a monitor 26. However, the person having no such a key can catch more detailed contents than a program guide on newspapers, etc., by means of the free sound signal.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides 1! The present invention relates to a transmitting/receiving 16 system that encrypts a part of the code so that only paying viewers can receive it correctly, and particularly relates to a broadcasting method C that encrypts either the video signal or the audio 16.

[Technical background of the invention and its 115 issues] In the paid broadcasting of American television video and audio, encryption was used to allow correct reception only to viewers who paid the fee. However, this system has the problem that viewers who do not pay the fee cannot fully understand the contents of the new program, and therefore visual acuity 11114 remains low and does not increase. This means that even if viewers have a latent desire to watch the program, they end up not watching it because they have little opportunity to learn about the content of the program.

The potential demand for viewing was buried.

FIG. 1 is a block diagram showing an encryption and decryption system in a conventional pay broadcast f2. The sending side 13 sends video 1 and audio 2
Each digital signal is time-division multiplexed by a multiplexing circuit 3 and encrypted by an encoder 4 using a certain encryption key 5.

The encrypted audio and video signals are transmitted via a satellite line or a wired line and sent to a receiver 11114. The recipient pays a fee, obtains the decryption key 11, and uses the decryptor 10 to perform decryption.

The decoded video and audio signals are separated into video and audio signals by a separation circuit 9 and outputted from a TV monitor 7 and a speaker 8, respectively. In such a configuration, if the recipient does not have the decryption key 11, the recipient cannot receive the decryption key 11 at all.
It is impossible to intuitively know what the program content is actually like. Even if you can intellectually know the program content from newspapers and magazines.

This is not enough to attract potential viewers.

[Purpose of the invention]

The purpose of the present invention is to
The purpose of the present invention is to provide a broadcasting method that can increase the viewer's desire to receive the program by releasing either one of the issues for free, and can make it possible to become a visual audience.

[Summary of the invention]

The present invention encrypts either video or audio by selectively operating the encoder in sending 4dfA, and on the receiving side, even those who do not pay the fee can correctly output the unencrypted information. This is a transmission/reception system designed to allow users to know part of the broadcast content.

〔Effect of the invention〕

According to the present invention, even viewers who do not pay fees can fully understand the broadcast content, so it is possible to make the number of viewers more visible, which ultimately leads to an increase in reception fees. On the other hand, the viewer side is also a newspaper.

Since it is possible to directly know the outline of the program content without relying on program guides such as magazines, it is possible to select programs in more detail and organically, which improves the service for 4N listeners. , both sending and receiving sides can bring ≦ two benefits.

[Embodiments of the invention]

Figure 9142 is a block diagram showing an embodiment of the present invention. This embodiment is an example in which only the video signal is encrypted without converting it into an audio signal, and is suitable for broadcasting sports programs. First, on the transmitting side 311, a digital video signal is added to a predetermined code using an encoder. Z3 (often a digital signal sequence) is encrypted, and the unencrypted audio signal 2] is multiplexed and transmitted using a multiplex circuit. Broadcasting signals transmitted via satellite lines or wired lines are converted into video and
The audio is separated and the audio signal is always output correctly at the output section n. On the other hand, the video signal is decoded by the decoding circuit using this actual image only by a person who has the decoding key 29 given to the viewer who pays the reception fee, and the correct output is monitored by the monitor 26.
+2 lines, anyone who does not have the key will not be able to output the correct output. However, from the audio No. 16 C2 obtained for free, the recipient can grasp the program contents in a much more detailed manner than the program information provided by newspapers, magazines, etc. C2 (=
Become. Here, the encoder 22 changes the input Kaihyakugo according to a predetermined algorithm, and the changing algorithm may be specified by the encryption key.

FIG. 113 is a block diagram showing another embodiment of the present invention. This time, the case is that the audio is encrypted but the video is not encrypted, and the rest is the same as in Fig. 2. Figure 2 shows 1: Suitable for sports programs, for example. In other words, in sports programs,
Because there is little audio commentary, the atmosphere can be recognized well with the audio, but it is difficult to understand the movement of the sport, so it is true (Those who want to watch Nispora will have to pay a fee to watch the video because the audio alone is not enough.)

On the other hand, FIG. 3 is effective for music programs and the like. Since music programs may be satisfied with just the audio, it is not a good idea for the sender to provide only the audio for free.

Therefore, the configuration shown in FIG. 3, in which only the video is provided free of charge, can be considered. In a music program, it is easy to judge whether or not it is necessary to watch a video of a singer or performer. However, without audio, there is little value as a music program, so viewers who want to enjoy a music program even more will pay a fee to listen to audio as well.

FIG. 4 is a block diagram showing another embodiment of the present invention.

On the transmitting side 74, the digital video signal ω and the digital audio signal 61 are time-division multiplexed by a multiplexing circuit 62.

The multiplexed digital signal is sent to an encoder 63 with an encryption key 65.
is encrypted using Here, the switching instruction circuit 64 encrypts either the audio or the video, for example, only the video signal, depending on the content of the program. Then, a code signal indicating that the Eirin signal has been encrypted is added to the control signal section and transmitted. The receiving side 75 indicates that only the video signal from among the received signals is encrypted. The control signal is extracted, and the switching instruction circuit 71 decrypts the encrypted one of the video and audio, that is, the video signal in this case, using the decryption key 72 in the decoder 70, and separates the audio signal as it is. to circuit 69.

The separation circuit 69 separates audio and video and connects the video monitor 67.
and sends it to the audio output cast beaker 68. In this configuration, the transmitter sends video depending on the program content.

Either one of the voices is encrypted, and the receiving side has information on whether or not it is encrypted.Even if a person does not have the decryption key 72, at least the unencrypted signal can be output.

FIG. 5 shows another embodiment of the invention. This invention is applied to high-definition television broadcasting. Various systems are being considered for high-definition television broadcasting.

Because both the video and audio have high quality.

Even the slightest deterioration has a large impact. Therefore, when applying the present invention to a high-definition television system, an encryption circuit is required.

A sufficient effect can be produced just by acting on a portion of the signal. For example, when a digital video signal is sampled at 8 bits/sample, it is not necessary to encrypt all 8 bits, and even if only 1 bit, for example, is encrypted, it will greatly affect the viewer. this is.

This means that an extremely simple encryption circuit can be used.

On the transmitting side 92, one bit of the high-definition digital A/8-bit video signal button is sent to a one-bit encoder 82 and encrypted using an encryption key 83.

The encoder output 1 bit, the remaining 7 bits, and the voice 81 are multiplexed by the multiplexing circuit 8 and sent to the transmission terminal 85.

On the receiving side 93, the input signal at the receiving terminal 91 is separated into an 8-bit video signal and a 14-bit audio signal using a separating circuit. Of the 8 bits of the video signal, the encrypted 1 bit is decrypted using a decryption key 89 obtained from a 1-bit decoder 88 (2) by paying a separate fee, and sent to the video monitor 86 along with the remaining 7 bits. In this configuration, the 1-bit encoder/decoder may act on the audio side instead of the video side.Also,
Of course, the number of bits to be encrypted may be the same.

The present invention can be implemented with various other modifications.

For example, in the embodiment shown in Figure 4, if either the video or the audio is encrypted, the viewer who does not have the decryption key on the receiving side will output both the video and the audio regardless of whether or not the decryption is performed correctly. You may also do so. This is close to a random signal because the encrypted signal is not decoded correctly.

It has no meaning when using digital encryption, but
When using an analog encryption method in which all signals are not necessarily random, there is a possibility that some information indicating the program content can be obtained even without correct decoding, so it is better to stop outputting even if the signal is erroneous. This is because it is better to output it. If the viewer does not have the decryption key for the output video or audio and the output is not correct, they can manually lower the level or turn it off, depending on their preference.

In addition, there are two ways to switch according to the program content C2 on the transmitting side: one is to do it manually for each program, and the other is to classify the broadcast contents into sports programs, music programs, etc. There are two methods of switching, and either can be used.

Further, in one or more embodiments, either the video signal or the audio signal is subjected to f2 encryption, but both may be encrypted. However, at that time, the encryption key at the receiving end is
In the case of a valid subscriber, both encrypted signals are trusted, and in the case of an invalid subscriber, only one of C2 and 1: acts.

That is, when broadcasting from the transmitting side, a signal indicating the type of signal is added and transmitted, and the receiving side can distinguish between these and perform processing corresponding to the signals.

Similarly, two different encryption keys are set for video signals and audio (No. 1 and No. 2), and valid subscribers are given both keys.

Either key may be distributed to inactive subscribers. At this time, both keys may be distributed to non-valid subscribers, however, it is necessary to prevent one of the keys from functioning effectively.

To achieve this, the IL1 number corresponding to the subscriber who is valid for broadcasting is also transmitted, and the receiving end is separately II)
Let me remember the number. Receive broadcast signals at the receiving end (I
After receiving 11, it is determined whether or not the received ID number is the same as the ID number stored in memory.If there is an identical ID number, it is valid, otherwise it is invalid. This can be determined and the action of the encryption key can be regulated accordingly.

In other words, scrambling does not simply mean encrypting (No. This refers to processing that yields a signal of

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional system. 2 to 5 are diagrams showing a system according to an embodiment of the present invention. 2), 40.60.80... video signal. 2], 41, 61.81... audio signal. 22.43, 65, 83... Encryption key. Representative patent attorney Kensuke Norichika (1 person) Figure 1 L--++ J Figure 2 1 L-==--+ +--++-~-11. Figure 8 S2 Figure 4

Claims (4)

[Claims] (1) In a system that broadcasts video and audio signals in pairs. The video signal or the audio signal is processed by a predetermined algorithm C.
2. A broadcasting system characterized in that the signal is converted and then broadcast, and a receiving terminal can reproduce the signal that has not been converted according to at least the predetermined algorithm. (2) Signal C converted according to a predetermined algorithm
The broadcasting system according to claim zi, characterized in that two separate signals are added and broadcasted. (3) The broadcasting system according to claim vJ1, characterized in that a predetermined algorithm is specified by an encryption key. (4) Video 1#11f depending on the broadcast content! i number or back door 1
100 f2 The broadcasting system according to claim 1, characterized in that conversion is performed according to a predetermined algorithm.