Abstract:
A data hiding method for hiding message data in media data and a data extracting method for extracting message data hidden in the media data. In the data hiding method, the message data are dispersedly hidden in the media data so that no third person can alter the message data. Specifically, the array elements of a message array are dispersedly hidden in a media array based on a status value S designating a specific array element in the media array when the media data and message data are expressed as the media array and the message array, respectively. The hiding method includes (a) a step of determining the j-th (j>/=0) status value Sj, (b) a step of determining the (j+1)-th status value Sj+1 based on the value Sj, the array element of the media array designated by the value Sj and the above-mentioned array element of the message array, and (c) a step of hiding data to be hidden in the array element of the media array designated by the value Sj+1.
Abstract:
PROBLEM TO BE SOLVED: To provide a cipher communication, system high in information security even though plural callers exist for a specific callee by adopting the server, which specifically conducts a decoding having secret keys, along with a transmitter and a receiver. SOLUTION: A transmitter 110 ciphers a message M by an open key ciphering means 112 and open keys P and N generated by a server 130 and a ciphered message M0 is transmitted to a receiver 120 by a ciphered message transmitting means 114. The receiver 120 generates a random number X by a random number generating means 122, the message M0, which is transmitted from the transmitter 110, is further ciphered by the number X in a ciphering means 124 and the ciphered message M1 is transmitted to the server 130. The server 130 decodes the transmitted and ciphered message M1 in a decoding means 136 employing the keys. The decoded message M2 is returned to the receiver 120 by a decoded message transmitting means 138.
Abstract:
PURPOSE: To efficiently composite a precise solid model by using drawing data. CONSTITUTION: Closed areas are detected on the basis of shape drawing data to generate a closed area list 100, a tree structure is detected 200, and the list is converted into a symbol group as a set of symbols of elements of the outlines of the closed areas and symbols of connection relations of the elements 300. When the symbol group has a specific symbol, the symbol group is divided into plural symbol groups on the basis of the symbol 400. The symbol group, matching is performed 500 and the attributes, e.g. area of the closed areas are detected 600. The symbol groups are classified into symbol groups of closed areas of the same shape, and the symbol groups are further classified into symbol groups of closed areas of the same area 700. Symbol groups of closed areas having children of the closed areas of the same area of the same shape are selected out of the symbol groups of the closed areas of the same area of the same shape 800 and the solid model is composited 900.
Abstract:
PURPOSE:To synthesize a solid model from one plan view and one or plural cross-sectional drawings by combining resective closed areas solidified by a closed area solidifying means based upon the positional information of respective closed areas. CONSTITUTION:A drawing sorting means 600 sorts inputted two-dimensional drawing data into plan data and sectional drawing data. A closed area recognizing means 700 groups closed areas having the same attribute based upon the attributes of detected closed areas. An area solidifying means 800 divides the sectional drawing data based upon the data of each detected closed area, solidifies the closed area based upon, the divided sectional drawing data and solidifies a closed area other than the solidified closed area and belonging to the same group as the solidified closed area by the same method as the solidified closed area. A solid model synthesizing means 900 synthesizes a solid model by combining respective solidified closed areas based upon the positional information of respective detected closed areas.
Abstract:
PURPOSE:To produce a solid model based on plural incomplete drawings. CONSTITUTION:The segments and curves of three drawings are calculated from the two-dimensional data on these drawings, and a wire frame model is produced based on those calculated segments and curves. The edge line of the wire frame model is compared with the segments or curves for correction of the frame model. Then the corrected wire frame model is converted into a sell division model. The conditions that correct at least one of three drawings are set by a Boolean equation, and a solid model is synthesized based on the combination of cells, i.e., the solution of the equation. When no solution is obtained from the equation, the candidate models are synthesized based on the optional combinations of cells. These candidate models are displayed in the order of higher resemblance. Meanwhile a candidate model is selected by an operator as a solid model when plural combinations of cells are obtained as the solutions. Then, three drawings are newly produced for the acquired solid model, and the original three drawings are completed based on these new drawings.
Abstract:
PROBLEM TO BE SOLVED: To provide a new system capable of supplying authentication information in a form which is inseparable from an image data. SOLUTION: An image is halved and authentication information to hide in one image is obtained from the other image itself. Objective image data photographed by a digital camera is divided into an area D1 for generating a hush value and an area D2 for hiding a hush value H. A digest-calculating part calculates H from data of D1 and ciphers it by a secret key different for each digital camera, etc., to hide D2 , hiding can be executed by operating a pixel value in a real space or a frequency space to a degree of not being recognized visually. In D2 , additional information such as a time stamp, positional information of GPS can be hidden before hiding data from D1 .
Abstract:
PURPOSE:To shorten preparation time and to simplify selection processing by evaluating whether or not there is any conflict in the adjacent relation of cells, assembling the respective cells based on the combination of cells having no conflict, and synthesizing a solid model. CONSTITUTION:Concerning the cell dividing model, in order to make a ridge line e1 existent, there are conditions that the ridge line e1 is made correspondent to a ridge line E1 of three drawings, the surfaces of any two cells among cells C1-C3 provided with the ridge line e1 cross (are not existent on the same plane) and only one cell is provided with the ridge line e1. Assuming that each cell is existent, a Boolean equation is applied as a normalizing formula so as to evaluate and calculate the combination (analysis) of assumption having no conflict. Based on the combination of cells having no conflict provided like this, the respective cells in the cell dividing model are selected and assembled, and several solid model candidates corresponding to a three-plane drawing are synthesized.
Abstract:
A method for providing a highly-safe and high-speed group key updating method. The method includes a step of executing a part of decoding processing for decoding an encrypted group key used for information decoding in a subscriber terminal before delivery of the group key, a step of delivering the group key and individual decoding information for each terminal device for executing a part of the remaining part of the decoding processing of the group key, and a step of executing in the subscriber terminal a group key decoding processing using the delivered decoding information and the result of the part of the decoding processing executed in advance
Abstract:
PROBLEM TO BE SOLVED: To provide the access of a high security level to data having high secrecy such as registrant's privacy data with high reliability. SOLUTION: An access management system includes an authorization engine 34 for controlling access to a registrant database 44 which stores registrant data including the registrant' privacy data and uses a prescribed privacy policy and condition data designated by a registrant to control the access to the registrant database 44. The authorizing engine 34 includes an authorization determining part 36 for determining an access type from an access request received from the outside and using access authorization data determined previously to the access request in conjunction with the access type with respect to the registrant data to control a reference to the registrant database based on the access request. COPYRIGHT: (C)2005,JPO&NCIPI
Abstract:
PROBLEM TO BE SOLVED: To provide an identification information generating device, and an identification information solving device capable of generating/using a derivative ID wherein an unauthorized server or the like can not discriminate a relationship between a user ID and the derivative ID while providing a relationship between the user ID and the derivative ID which is another ID for identifying a user. SOLUTION: An ID generating device has a derivative value generating part for generating a derivative value, a user ID enciphering part for generating an enciphered ID generated by enciphering information including the user ID and the derivative value, and a derivative ID generating part for generating the derivative ID on the basis of the enciphered ID. An ID solution device has an enciphered ID extracting part for extracting the enciphered ID included in the derivative ID, an enciphered ID deciphering part for deciphering the enciphered ID on the basis of a decipher key with respect to a cipher key to generate a deciphered ID, and an ID determining part for determining that the derivative ID has been generated from the user ID when one part of the deciphered ID matches information generated on the basis of the user ID. COPYRIGHT: (C)2004,JPO&NCIPI