Abstract: In an encrypted transmission system composed of one transmission apparatus 10 and twenty-eight reception apparatuses A1-G4 that are classified into seven groups A-G, two secret key exclusively selected out of a total of fourteen secret keys are distributed beforehand to each group. The transmission apparatus 10 encrypts the same message M using one of the two secret keys distributed to each group and sends each group a message M encrypted with one of the group's secret keys. The reception apparatuses each decrypt the received cryptogram separately using each of the secret keys assigned to the of group to which each reception apparatus belongs, judge whether either of the two decryption results conforms to a predetermined rule, and specify the correct decryption result.

Abstract: An information processing system includes a first information processing apparatus and a second information processing apparatus arranged separate from the first information processing apparatus and capable of exchanging a signal with the first information processing apparatus. The first information processing apparatus includes a first key generator for generating a first key, and a first encrypting unit for encrypting data using the first key generated by the first key generator to generate first encrypted information. The second information processing apparatus includes a second key storage unit for storing a second key, and a second encrypting unit for encrypting the first key using the second key stored in the second storage unit to generate second encrypted information.

Abstract: A transmission apparatus 100 includes a secret key storage unit 103 that stores three secret keys K1, K2 and K3, a secret key selection unit 104 that selects one secret key Ks from the secret keys, a message generation unit 106 for generating a message M used as a carrier for indicating a secret key, an encryption module 105 for generating a cryptogram Ca by encrypting the generated message M using the secret key Ks, an encryption module 107 for generating a cryptogram Cm by encrypting the message M using the message M itself as the secret key, and two transmission units 111 and 112 for transmitting the cryptograms Ca and Cm to the reception apparatus 200 to indicate the selected secret key Ks.

Abstract: A method of printing bar codes, comprising the steps of reading destination data from a piece to be delivered, on which the destination data is provided and which has at least first to third regions, printing a bar code representing the destination data on the piece, and printing on the piece a bar code representing sender's data when the piece is found to be a destination-unknown one.

Abstract: An information recording/reproducing apparatus includes a first processing unit, a link information generating unit, a link information storage unit, and a second processing unit. The first processing unit processes information constituted by a plurality of information units and subjected to a recording/reproducing operation. The link information generating unit generates link information representing the relationship between arbitrary information units of the information units constituting the information. The link information storage unit stores the link information generated by the link information generating unit. The second processing unit performs predetermined processing with respect to the link information when an information unit corresponding to the link information stored in the link information storage unit is processed by the first processing unit.

Abstract: A bar code encoding system comprising a representing unit for representing an input character by an information symbol of m bits excluding a bit pattern of all "0" bits, a calculating unit for subjecting a series of a k-number of information symbols to error-correction encoding and calculating a check symbol series of a q-number of check symbols, a converting unit for respectively converting an n=(k+q) number of symbols to predetermined bar code patterns, and arrangement converting unit for converting arrangement of the n-number of symbols so that at most three bar code patterns corresponding to the check symbols may not be consecutively arranged.

Abstract: A recording/reproducing apparatus includes a video memory having a capacity of at least one frame, a video processor for recording movie image data on a first track of a recording medium via the video memory, and for reproducing movie image data recorded on the first track of the recording medium via the video memory, an audio processor for recording at least one of audio data input via an input terminal and still image data constructed by movie image data selectively read out from the video memory into a plurality of channels of a second track of the recording medium, and for reproducing data recorded in the plurality of channels of the second track and a buffer for writing the reproduced still image data from the second track of the recording medium into the video memory.

Abstract: An image/audio information recording/reproduction apparatus has a first recording device for receiving a first electrical signal representing image information and recording the image information on a dynamic recording medium of a given type, a static recording medium of a given type for storing a second electrical signal digitally representing audio information accompanying the image information, and a second recording device which is electrically connected to the static recording medium. The second recording device determines a memory address in the static recording medium of audio information accompanying the image information in a manner corresponding to a recording position of the image information on the dynamic recording medium, and records the audio information in the static recording medium in accordance with the determined memory address. The static recording medium includes a non-volatile semiconductor memory, such as an electrically erasable programmable read only memory.

Abstract: The invention relates to a reproducing apparatus for reproducing digital signals. The apparatus comprises means for detecting the recorded data from the medium and generating digital data signals corresponding of the recorded data having a first predetermined bit rate, expansion means for converting the digital data signals from the detecting means into expanded digital signals having a second bit rate lower than the first bit rate, and means coupled to the expanding means for extracting the portions of the expanded digital signals corresponding to the synchronous words. Thus, it can be to provide a compact magnetic recording and reproducing apparatus which is more reliable, and less costly to manufacture, utilizing a lower working speed synchronous detector.

Abstract: In a digital data modulation circuit, a digital data block formed of k words, each of which includes m-bit binary data, is input to an error-correcting coding circuit which adds (n-k) check words to the input data block. The error-correcting coded data block is supplied to an arithmetic operation circuit, which calculates the number of "1" bits and the number of "0" bits to be included in the coded data block output from the error-correcting coding circuit so that the difference between the number of "0" bits and the number of "1" bits included in the coded data blocks which have been output from the error-correcting coding circuit approximates 0 and calculates one control word corresponding to the calculated number. The coded data block output from the error correcting coding circuit is supplied to a modulo-two adder which adds the control word to every word belonging to the coded data block.

Abstract: In an encode method in which a binary data stream is divided into data words each of three bits. Each of the data words is encoded into a binary code word of 9 bits. In the method, a code word to be encoded is encoded in consideration of a code word preceding the code word and two code words succeeding the code word. Then, one of the first two code bits in each code word and two of the last five code bits in the preceeding code word are inverted according to a pattern of code bits "0" and "1" in both the code words. As a result, consecutive 5 to 19 code bits "0" are arrayed between two adjacent code bits "1" in the code word stream.