JPH06296175A - Scrambler and descrambler - Google Patents

Abstract

PURPOSE:To provide the scrambler and the descrambler able to descramble correctly data after interpolation processing when the scrambler and the descrambler are adopted for a communication system implementing interpolation processing with respect to the scrambler used when a digital vidbo signal and a voice signal are communicated. CONSTITUTION:A divider 11 divides input data in the unit of data of the interpolation processing executed at a location of reception or reproduction. Then a PN adder 12 receives division data outputted from the divider 11 to provide a ciphering output of the division data. In this case, the PN adder 12 generates a pseudo random number (PN) based on a kind of a random number series and all division data related to each other are subject to exclusive OR processing in the interpolatioon processing. Finally a synthesizer 13 synthesizes the division data after being processed by the PN adder 12 with reverse processing of the divider 11 to provide an output of the data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scrambler and a descrambler used when secretly communicating or recording / reproducing a digital video signal or a digital audio signal by using a wired or wireless or storage medium.

[0002]

2. Description of the Related Art Conventionally, scrambling for encrypting and communicating digital video signals and digital audio signals has been performed by adding pseudo random numbers (hereinafter referred to as PN). For scrambling digital audio PN addition, see, for example, "Cryptography and Information Security" (Shokodo Deide; Shigeo Tsujii et al.), P.
~ Introduced on page 179. FIG. 7 shows a conventional scrambler. Here, 71 is a random number generator, and 72 is an exclusive OR device.

In the conventional scrambler configured as described above, input data composed of video data or audio data is input, and the random number generator 71 generates a PN based on the seed of the random number, which is exclusive. The logical sum device 72 outputs the result of the bitwise exclusive OR of the input data and the PN as scrambled data.

The conventional descrambling device has the same structure as the scrambling device described above, and is composed of a random number generating device 71 and an exclusive OR device 72 as shown in FIG. In the conventional descrambling device configured as described above, scrambled video data or audio data is input as input data, and the random number generation device 71 generates a PN based on a seed of random numbers and performs an exclusive OR operation. Device 7
2 outputs the result of the bitwise exclusive OR of the input data and the PN as descrambled data. Here, the seed of the random number input to the random number generator 71 is the same as the seed of the random number used when the input data is scrambled.

At this time, due to the property of exclusive OR,

[0006]

[Equation 1]

Therefore, when the descrambling device performs the exclusive OR of the input data and the descramble, the same P as that used when the descrambled input data is scrambled by the scramble device is used.
Only when N is bitwise exclusive ORed with the input data descrambled with the same bitwise correspondence,
Correctly scrambled.

For example, if the data is (10110110)
Then, when PN is (10101010), data and PN
The result of the exclusive OR for each bit, that is, the scrambled data is (00011100). In order to descramble this, the same PN must be bitwise exclusive ORed with the same bit correspondence.
It can be seen that the result of the bitwise exclusive OR of the scrambled data and the PN, that is, the descrambled data, is (10110110), which is correctly descrambled.

When the scrambler and the descrambler of the conventional example are actually used, the communication system shown in FIG. 8 is constructed. Here, 81 is a scrambler, 82 is a transmitter, 83 is a communication channel, 84 is a receiver, and 85 is a descrambler.

In the communication system configured as described above, the scramble device 81 first scrambles the data based on the seeds of random numbers, and then the transmitter 82 uses the data output from the scramble device 81 as the transmission method. It is converted into suitable transmission data, and is transmitted through a communication path 83 such as a wired or wireless or storage medium. In addition, the receiving device 84
Receives the transmission data transmitted through the communication path 83, and processes the received data by a process suitable for the process in the transmitting device 82. Finally, the descrambler 85 descrambles the data processed by the receiver 84 based on the seeds of random numbers.

As an example, a case where a conventional scrambler and a descrambler are used when video data composed of a plurality of frame data is communicated by a conventional communication system will be described. Here, it is assumed that each frame data before being scrambled is divided into divided data Dab, b indicates a frame, and a indicates a position of the divided data in the frame. Moreover, each position of Dab is represented by (a, b). That is, the position of D12 is (1, 2)
Express. Similarly, PN is represented by PNab, and scrambled data is represented by Cab.

First, the scrambler is shown in FIG.
The data shown in FIG. 10 is associated with the PN shown in FIG. 10B and scrambled by the bitwise exclusive OR, and as a result, the scrambled data Cab shown in FIG. 10C is obtained. .

[0013]

[Equation 2]

That is, D11 is PN11 and D12
, PN12 is bitwise exclusive ORed and scrambled to obtain C11 and C12. When descrambling, if the divided data are arranged in the same order as when scrambling as shown in FIG.
Since it is descrambled using the PN shown in 0 (b),
Since the same PN that was used when the divided data was scrambled is used for descrambling each divided data, it is descrambled correctly.

[0015]

[Equation 3]

As a special example of the communication system shown in FIG. 8, there is a recording / reproducing system shown in FIG. here,
Reference numeral 91 is a scramble device, 92 is a recording device, 93 is a storage medium, 94 is a reproducing device, and 95 is a descrambling device.

In the recording / reproducing system configured as described above, the scrambler 91 first scrambles the data based on the seeds of random numbers, and then the recorder 92 records the data output from the scrambler 91. It is converted into recording data suitable for the method and recorded in the storage medium 93. The reproducing device 94 reproduces the recorded data recorded in the storage medium 93, and reproduces the reproduced data.
Process with a process suitable for the process in 2. Finally, the descrambling device 95 descrambles the data processed by the reproducing device 94 based on the seeds of random numbers.

By the way, in a receiver of a communication system for transmitting and receiving video data and audio data, interpolation processing may be performed by utilizing the property that the video data and audio data have a high correlation with neighboring data. This interpolation process is
When an error is multiplexed on the communication path, in order to reduce this error as much as possible, the error data is replaced with neighboring data. Considering the case of interpolation processing of video data composed of a plurality of frames as an example, a group of several pixels is used as a data unit for interpolation. Hereinafter, the data of this interpolation data unit will be referred to as interpolation unit data. In this case, as the former interpolation process, there is, for example, a process of interpolating an erroneous data unit with a data unit located at the same position in the immediately preceding frame.

When the video signal recorded on the storage medium is reproduced, special reproduction may be performed. There are three types of special playback: rewind playback, slow playback, and fast-forward playback. Rewind reproduction in the digital storage medium is reproduction in the reverse direction, and while the tape is rotated in the reverse direction, the frames are reproduced in the reverse order of the normal reproduction. Slow reproduction is reproduction at a slower speed than usual, and one frame of data is reproduced and displayed over the time required to normally reproduce several frames. Fast-forward playback is to play back at a speed faster than normal, and to play back and display data for several frames in the time for playing one frame normally.

[0020]

However, in the conventional scrambling device and descrambling device having the above-mentioned configuration, the data generated by the interpolation process in the receiving device of the communication system in which these devices are actually used. Had the first problem that it could not be descrambled correctly. The reason is shown below.

In the receiver of the conventional communication system using the scrambler and descrambler of the conventional example, when the above-mentioned interpolation processing is performed, the receiver detects erroneous data, and the neighboring interpolation units are detected. Replaced with data. After that, the data output from the receiving device is descrambled by the descramble device. This descramble is, as described above, the PN exclusive-ORed with the data by the scrambler on the transmission side,
It is realized by exclusive ORing the same PN with the same bit correspondence. At this time, since the PN cycle spans a plurality of interpolation unit data, the PN corresponding to each interpolation unit data is different.

Therefore, the interpolation unit data which has no error and is not interpolated is descrambled correctly because the same PN as when scrambled is subjected to exclusive OR for each bit corresponding to the same bit. However, since the interpolation unit data generated by the interpolation is replaced with the neighboring interpolation unit data, even if the PN used in the scrambler is made from the seed of random numbers and the exclusive OR is performed for each bit. , PN used when the neighboring interpolation unit data used for interpolation is scrambled.

As an example, when video data composed of a plurality of frame data is communicated in a communication system for performing interpolation processing, the conventional scrambler and descrambling apparatus are used to descramble the data after interpolation processing. Shows the case of processing with. Here, it is assumed that each frame data is divided into interpolation unit data as divided data. In addition, the interpolation process is a process for replacing erroneous divided data with divided data at the same position in the immediately preceding frame. Also in the conventional example, it is assumed that the scrambled divided data are arranged as shown in FIG.

Here, the data arranged as shown in FIG. 10C is scrambled using the PN shown in FIG. 10B. C12, C22, C33 and Cn
3A has an error, and the data after being interpolated by the data C11, C21, C32, and Cn2 at the same position in the frame immediately before that is shown in FIG. After that, even if descrambling is performed using the PN shown in FIG. 10B, for example, the data C11 at the interpolated position (1, 2) is P
It will be descrambled using N12. However, since C11 is scrambled using PN11, even if PN12 is exclusive-ORed bit by bit, it is not descrambled correctly. Similarly (2, 2),
The data at the positions (3, 3) and (n, 3) are not descrambled correctly.

As described above, there is a problem that the interpolation unit data at the interpolated position is not descrambled correctly. Therefore, in the conventional scrambler and descrambler, when used in a communication system that performs interpolation processing, there is a problem that a correct descramble operation cannot be performed for the interpolation processing part.

In view of the above point, the present invention enables the interpolation of an error to be realized when a scrambler and a descrambler are used in a communication system for performing interpolation processing.
A first object of the present invention is to provide a scramble device and a descramble device that can correctly descramble the interpolation processing part of the data after the interpolation processing is performed in the receiving device of the communication system.

Further, in the conventional scramble apparatus and descrambling apparatus having the above-mentioned structure, when these apparatuses are used in the recording / reproducing system for special reproduction, the video data in special reproduction cannot be descrambled correctly. There was a second problem called. The reason for this is shown below.

A video signal composed of a plurality of frame video signals recorded / reproduced on / from the storage medium reproduces the frame video signals recorded during normal reproduction in the same order as when they were recorded. However, in the case of special reproduction, the recorded frame video signals are reproduced in a different order from when they were recorded, or a frame video signal different from that at the time of recording is produced and reproduced. As a specific example, in rewind reproduction, reproduction is performed in the reverse order of recording, in slow reproduction, the same frame video signal is continuously reproduced, and in fast-forward reproduction, several frame video signals are reproduced. A frame video signal is created and used as a playback frame video signal.

When performing special reproduction as described above,
The video signal input to the recording device does not match the video signal output from the playback device. Therefore, in order to correctly descramble the video signal output from the reproducing apparatus at this time, the PN generated from the random number seed cannot be properly descrambled unless it is also used for the special reproduction process. That is, PN is used in the reverse order when rewinding, and the same PN is used in slow playback.
Must be repeatedly used for several frames, and in fast-forward reproduction, one frame of PN must be created from several frames of PN. These processes require complicated control, and an additional memory for PN and video data is required to realize the processes.

As an example, when recording / reproducing video data composed of a plurality of frame data in a recording / reproducing system for special reproduction, the data after special reproduction processing is performed by using a conventional scrambler and descrambler. The case where processing is performed by the descrambling device is shown. Here, it is assumed that each frame data is divided as the divided data Dab into the minimum data unit when performing fast-forward reproduction. Also in this conventional example, it is assumed that the divided data after being scrambled are arranged as shown in FIG. At this time, scrambling is performed using the PN shown in FIG.
It is assumed that it is performed using.

First, the case of descrambling after performing fast-forward reproduction will be described. Here, it is assumed that the fast-forward reproduction is realized by a process of alternately using divided data from two frames to form one frame. As a result, the data after special reproduction is formed as shown in FIG. In order to descramble this data, even if the PN shown in FIG. 10 (b) is used as it is, it cannot be descrambled correctly, PN for two frames is generated, and fast-forward reproduction is performed using the PN for two frames. In this case, the PN for one frame must be created by the same process as that for creating one frame from two frames. This complicates the process and increases the amount of memory required. Faster fast-forward playback does more complicated processing, so descramble becomes more complicated.

Further, FIG. 11 (c) shows an example of slow reproduction, and FIG. 11 (d) shows an example of data to be descrambled for rewind reproduction. Complex processing is required.

As described above, P generated in the same way as in the scrambler from the seeds of random numbers used in the scrambler
If N is simply sequentially generated and bitwise exclusive OR is performed as in the case of no special reproduction, descrambling cannot be performed correctly, and complicated processing is required to perform descrambling correctly. there were.

In view of the above point, a second object of the present invention is to provide a scramble device and a descramble device that can easily and properly descramble even in special reproduction in a recording / reproduction system for special reproduction. .

[0035]

According to a first aspect of the present invention, there is provided a dividing device for dividing input data into data units in which interpolation processing is performed and outputting the divided data as divided data, and for all divided data associated with each other in the interpolation processing. And an synthesizing device for synthesizing the divided data processed by the encrypting device by a process reverse to that of the dividing device and outputting as output data.

The second invention uses a video signal composed of a plurality of frame data as input data, divides the input data into minimum data units that can be restored in special reproduction processing, and outputs the divided data as divided data. In the trick play process, an encryption device that repeats the same randomization process for all the divided data that are related to each other, and the divided data that has been processed by the encryption device are combined by the reverse process of the dividing device. It is composed of a synthesizer that outputs as output data.

[0037]

In the scrambler and the descrambler according to the first aspect of the present invention, the dividing device divides the input data into the minimum data units for which interpolation processing is performed and outputs the divided data as the divided data, and the randomizing device interpolates. The same randomization process is performed on all divided data that are related in the process. As a result, all the divided data items to be interpolated are scrambled / descrambled by the same process, so that the interpolated divided data items are correctly descrambled.

The scrambler and the descrambler according to the second aspect of the present invention are configured as described above, and the dividing device divides the input data into the minimum data units that can be restored in the special reproduction process and outputs the divided data as the divided data. The same randomization process is performed on all the divided data that are related to each other in the special reproduction process. As a result, even if the order of divided data differs between scrambling and descrambling due to special playback, the range of movement is a position where they are related in special playback, and the descramble processing for divided data is the same. So it is descrambled correctly.

[0039]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a scrambler according to the first embodiment of the present invention.

In FIG. 1, 11 is a dividing device for dividing input data into data units for interpolation processing and outputting as divided data, and 12 is a PN adder for adding the same PN to all related divided data in interpolation processing. , 13
Is a synthesizing device for synthesizing the divided data by a process reverse to that of the dividing device 11 and outputting as output data.

The operation of the scrambler according to this embodiment having the above-mentioned structure will be described below. First, the dividing device 11 divides the input data and outputs it as divided data. The dividing device 11 at this time divides the input data into data units of the interpolation processing performed at the place of receiving or reproducing. Next, the PN adder 12 receives the divided data output from the dividing device 11, encrypts the divided data, and outputs the encrypted divided data. At this time, the PN adder 12 generates a PN based on the seed of the random number, and uses the same PN for all the related divided data in the interpolation processing.
Exclusive-or. Finally, the synthesizer 13 divides the divided data processed by the PN adder 12 into the divider 11
The output data is synthesized by the reverse processing of the above and output as output data.

The descrambling device according to the first embodiment of the present invention has the same configuration as the scrambling device shown in FIG. 1, and the dividing device 11, the PN adder device 12, and the synthesizing device 1 are used.
It consists of 3.

The operation of the descrambling apparatus of the first embodiment constructed as above will be described below. The descrambler according to the present embodiment receives as input data the data that has been scrambled by the scrambler according to the present embodiment and has been subjected to interpolation processing at the receiving or reproducing location. First, the dividing device 11 divides the input data and outputs it as divided data. The dividing device 11 at this time operates similarly to the dividing device 11 in the scrambler of the first embodiment. Next, in the PN adder 12, the divider 1
The divided data output from 1 is input, and the divided data is decoded and output. At this time, the PN adder 12 generates the PN based on the same seed of the random number used for scrambling the divided data in the PN adder 12 in the scrambler of the present embodiment, and it is related in the interpolation processing. The same PN is exclusive-ORed with respect to all matching divided data. Finally, the synthesizer 13 synthesizes the divided data processed by the PN adder 12 by the same processing as the scrambler of the first embodiment and outputs it as output data.

As described above, according to the first embodiment, even when the interpolation process for replacing the erroneous divided data with the neighboring divided data is performed before descramble,
Since the same PN is added to all the divided data items to be interpolated, the divided data items obtained by interpolation can be descrambled correctly.

The PN in the first embodiment of the present invention
The adder performs the same processing for all the divided data that are related to each other regarding the interpolation processing, but even if it is configured to perform the same processing for all the input divided data, the same effect is obtained. It goes without saying that it will be done.

FIG. 2 is a block diagram of a scrambler according to the second embodiment of the present invention. In FIG. 2, 21 is a division device, 22 is a block encryption device that performs block encryption processing, and 23 is a combination device. Here, the block cipher is such that a certain multi-bit data is made into one block, the block data is shuffled by a key instruction, and as a result, block data having the same bit length as before the shuffle is output as randomized data. It is a code.

The operation of the scrambler according to the second embodiment having the above configuration will be described below. The dividing device 21 is the dividing device 11 of the first embodiment shown in FIG.
Similarly, the input data is divided and the divided data is output. Next, in the block encryption device 22, the key and the division device 2
The divided data output from 1 is input, and the divided data is encrypted and output according to the instruction of the key. At this time, the block encryption device 22 uses a block smaller than the divided data and performs the block encryption processing so that the processing is completed within the divided data. That is, the encryption processing is performed so as not to span the divided data. Furthermore, the block encryption device 22
Encrypts all divided data with the same process using the same key. Finally, the synthesizing device 23 is similar to the synthesizing device 13 of the first embodiment shown in FIG.
The divided data after being processed in 2 are combined and output as output data.

A descrambling device according to the second embodiment of the present invention is shown in FIG. In FIG. 3, 31 is a dividing device, 32 is a block decoding device that performs block decoding processing, and 33 is a synthesizing device. Here, the block decryption process is a decryption process for data encrypted by block cipher.

The operation of the descrambling apparatus of the second embodiment constructed as above will be described below.
The descrambler of the second embodiment inputs the data after being scrambled by the scrambler of the second embodiment shown in FIG. 2 and subjected to the interpolation processing at the place of reception or reproduction as input data. The dividing device 31 divides the input data and outputs the divided data as in the scramble device of FIG. Next, in the block decryption device 32, the key and the divided data output from the dividing device 31 are input, and the divided data is decrypted and output according to the instruction of the key.

Here, the block decryption device 32 performs a decryption process for the process in the block encryption device 22 in the scramble device of the second embodiment shown in FIG. The decoding process is performed using a block having the same size as that used in the decoding process. Furthermore, the block decryption device 32 decrypts all the divided data with the same processing using the same key. Finally, like the synthesizer 23 of the scrambler of the second embodiment shown in FIG. 2, the synthesizer 33 synthesizes the divided data processed by the block decoder 23 and outputs it as output data.

As described above, according to the second embodiment, when the divided data is received or reproduced, the interpolation processing for replacing the erroneous divided data with the neighboring divided data is performed before the descrambling. Even in this case, since the same block cipher processing is performed on all the divided data pieces to be interpolated, the divided data pieces obtained by the interpolation can be descrambled correctly.

Although the block encryption device according to the second embodiment of the present invention performs the same processing on all the divided data pieces related to each other regarding the interpolation processing, it performs the same processing on all the input divided data pieces. It goes without saying that the same effect can be obtained even if the same processing is performed.

FIG. 4 is a block diagram of a scrambler according to the third embodiment of the present invention. In FIG. 4, reference numeral 41 denotes a dividing device which uses a video signal composed of a plurality of frame data as input data, divides the input data into minimum data units that can be restored, and outputs the divided data as divided data. A PN adder that adds the same PN to a certain piece of divided data, and 43 is a combiner that combines the divided data by a process reverse to that of the divider 41 and outputs it as output data.

The operation of the scrambler according to the third embodiment having the above configuration will be described below. Dividing device 41
Divides the input data and outputs it as divided data. At this time, the dividing device 41 divides the data into the minimum image constituent elements. Here, the minimum component of video is the smallest block of data that can be a picture without any problem, and differs depending on the recording / reproducing system used, and is, for example, a block for compression encoding, or a block for interpolation. It may be a data unit, a pixel, or a frame.

Next, in the PN adder 42, the divider 4
The divided data output from 1 is input, and the divided data is encrypted and output. At this time, the PN adder 42 generates a PN based on the seed of the random number, and exclusively ORs the same PN with respect to the divided data at the same position in each frame. Finally, the synthesizing device 43 synthesizes the divided data processed by the PN adding device 42 by a process reverse to that of the dividing device 41 and outputs it as output data.

The descrambling device according to the third embodiment of the present invention has the same structure as the scrambling device according to the third embodiment of the present invention shown in FIG. 4, and includes a dividing device 41 and a PN adding device. 42 and a synthesizer 43.

The operation of the descrambling device of the third embodiment configured as described above will be described below. The descrambler in this embodiment inputs as input data the data after the special reproduction processing is performed at the receiving or reproducing place. The dividing device 41 divides the input data and outputs it as divided data. At this time, the dividing device 41 is configured as shown in FIG.
An operation similar to that of the dividing device in the third embodiment shown in FIG. Next, in the PN addition device 42, the divided data output from the dividing device 41 is input, and the divided data is decoded and output. At this time, the PN adder 42 generates a PN based on the same seed of the random number used when the divided data is scrambled, and generates the same PN for the divided data at the same position in each frame. Exclusive OR. Finally, the synthesizer 43 synthesizes the divided data processed by the PN adder 42 and outputs it as output data, like the synthesizer 43 of the scrambler shown in FIG.

Here, by the special reproduction process, the video data input to the descrambler is different from the video data output from the scrambler. Limited to the same position in different frames. Therefore, according to the scrambler and the descrambler of the third embodiment, all the divided data at the same position in each frame are scrambled or descrambled by the same process, so that the data after the special reproduction process is descrambled correctly. it can.

As described above, according to the third embodiment, in the recording / reproducing system for performing special reproduction, it is possible to configure the scramble device and the descramble device that can easily and properly descramble even during special reproduction.

Incidentally, the PN in the third embodiment of the present invention.
The adder is configured to exclusive OR the same PN with respect to the divided data at the same position in each frame, but exclusively OR the same PN with respect to the divided data at the same position in each frame, and It goes without saying that the same effect can be obtained even if the same PN is added to all the related divided data regarding the interpolation processing performed at the place where the data is reproduced. Data can be descrambled correctly.

The PN in the third embodiment of the present invention
The adder performs the same processing for the divided data at the same position in each frame, but the same effect can be obtained even if it is configured to perform the same processing for all input divided data. Needless to say.

FIG. 5 is a block diagram of a scrambler according to the fourth embodiment of the present invention. In FIG. 5, 51 is a dividing device, 52 is a block encryption device that performs the same processing on divided data at the same position in a frame, and 53 is a combining device.

The operation of the scrambler of this embodiment having the above-mentioned structure will be described below. The dividing device 51 divides the input data and outputs it as divided data. At this time, the dividing device 51 performs the same operation as the dividing device 41 in the scrambler of the third embodiment shown in FIG. Next, the block encryption device 52 inputs the divided data output from the dividing device 51, encrypts the divided data, and outputs the encrypted divided data. At this time, the block encryption device 52
Then, the block cipher using a block smaller than the divided data is realized, and the processing is completed within the divided data. That is, an encryption process is performed that does not extend between divided data. Further, the block encryption device 52 encrypts all the divided data by the same process. Finally, the synthesizer 53
Outputs the combined data after being processed by the block encryption device 52 as output data. At this time, the synthesizer 53 performs the same operation as the synthesizer 43 in the scrambler of the third embodiment shown in FIG.

A descrambling device according to the fourth embodiment of the present invention is shown in FIG. In FIG. 6, 61 is a dividing device, 62 is a block decoding device, and 63 is a synthesizing device.

The operation of the descrambling device of this embodiment constructed as described above will be described below. Dividing device 61
Divides the input data and outputs it as divided data. At this time, the dividing device 61 performs the same operation as the dividing device 51 in the scrambler of the present embodiment shown in FIG.
Next, the block decryption device 62 receives the divided data output from the dividing device 61, encrypts the divided data, and outputs the encrypted divided data. At this time, the block decoding device 62
Decryption processing is performed with respect to the processing in the block encryption device 52 of the fourth exemplary embodiment shown in FIG. 5, and the same processing is performed for all divided data. Finally, the synthesizing device 63 synthesizes the divided data processed by the block encrypting device 62 and outputs it as output data, as in the synthesizing device 53 of the fourth embodiment shown in FIG.

Here, the special reproduction process causes the video data input to the descrambler to be different from the video data output from the scrambler. However, as described above, the changing position is Limited to the same position in different frames. Therefore, in the scrambler and descrambler of the fourth embodiment, all the divided data at the same position in each frame are scrambled or descrambled by the same block encryption processing, so that even the data after the special reproduction processing is properly Can be scrambled.

As described above, according to the fourth embodiment, in the recording / reproducing system for performing special reproduction, it is possible to configure the scramble device and the descramble device that can easily and properly descramble even during special reproduction.

The block encryption apparatus according to the fourth embodiment of the present invention is configured to perform the same processing on the divided data at the same position in each frame, but the divided data at the same position in each frame is processed. It goes without saying that the same effect can be obtained even if the configuration is such that the same processing is performed for all divided data that are related to each other regarding the interpolation processing performed at the place where the video data is reproduced.
Furthermore, the data interpolated by the interpolation process can be descrambled correctly.

In the first, second, third and fourth embodiments of the present invention, the signal after the interpolation processing is descrambled. It goes without saying that the same effect can be obtained even if the interpolation processing is performed after the descrambling.

[0070]

As described above, according to the first aspect of the present invention, even if the interpolation process is performed before the descrambling, the scrambled data can be properly descrambled. Devices and descramblers can be configured. Therefore, by using the scrambler and the descrambler of the present invention, the scrambler and the descrambler can be applied to the communication system that performs the interpolation processing in the receiver, and the practical effect is large.

According to the second invention as described above,
In a recording / playback system that performs special playback with a playback device,
A scramble device and a descramble device that can be properly descrambled by a simple process even during special reproduction can be configured, and the practical effect thereof is great.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a scrambling device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a scrambler according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a descrambling device according to a second embodiment of the present invention.

FIG. 4 is a block diagram of a scrambler according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a scrambler according to a fourth embodiment of the present invention.

FIG. 6 is a configuration diagram of a descrambling device according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram of a conventional scrambler.

FIG. 8 is a configuration diagram of a communication system using a scramble device and a descramble device.

FIG. 9 is a configuration diagram of a recording / reproducing system using a scrambler and a descrambler.

FIG. 10 shows an example of data before being scrambled by a conventional scrambler and descrambler, PN used, and data after scramble.

FIG. 11 is a diagram showing an example of data after interpolation processing and special reproduction are performed in the communication system.

[Explanation of symbols]

 11, 21, 31, 41, 51, 61 Splitting device 12, 42 PN addition encryption device 22, 52 Block encryption device 32, 62 Block decryption device 13, 23, 33, 43, 53, 63 Combining device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hironori Murakami 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] 1. A dividing device that divides input data into data units in which interpolation processing is performed and outputs as divided data, and an encryption device that repeats the same randomization processing for all related divided data in interpolation processing. A scrambler comprising: 2. A dividing device for inputting a video signal composed of a plurality of frame data as input data, dividing the input data into minimum data units that can be restored in special reproduction processing, and outputting as divided data, and in the special reproduction processing. A scrambler comprising an encryption device that repeats the same randomization process for all related divided data. 3. An encryption device for performing a block encryption process completed within divided data with an encrypted block smaller than the divided data.
The scrambler described. 4. An encryption device for performing block encryption processing completed within divided data with an encrypted block smaller than divided data.
The scrambler described. 5. A dividing device that divides input data into data units in which interpolation processing is performed and outputs as divided data, and an encryption device that repeats the same randomization processing for all related divided data in interpolation processing. A descrambling device comprising: 6. A dividing device for inputting a video signal composed of a plurality of frame data as input data, dividing the input data into minimum data units that can be restored in special reproduction processing, and outputting as divided data, and in the special reproduction processing. A descrambling device comprising an encryption device that repeats the same randomization process for all related divided data. 7. An encryption device for performing block encryption processing completed within divided data with an encrypted block smaller than divided data.
The descrambler described. 8. An encryption device for performing a block encryption process completed within divided data with an encrypted block smaller than the divided data.
The descrambler described.