JP3528876B2 - Drawing information protection device and operation method of drawing information protection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drawing information protection device for detecting illegally modified drawing information.

[0002]

2. Description of the Related Art In recent years, design drafting using a CAD (Computer Aided Design) system has become widespread, and drafted drawings are being managed as electronic information. Along with that, how to digitize the drawing inspection process, and the forgery and the stamp data and drawing data obtained as a result of the inspection
An important issue is how to protect from unauthorized modification such as tampering.

Conventionally, drawing inspection work is performed by a person in charge of drawing inspection by stamping or signing a printed drawing. When digitizing this drawing inspection process by using a CAD system, drawing a figure corresponding to a seal imprint or a signature on a CAD drawing can be easily realized by the original drawing function of the CAD system. However, in a system that only creates a stamp or signature with the drawing function, it is possible to use the drawing function to forge the stamp or signature on the drawing before the drawing, or falsify the stamp or sign after the drawing. Is also easy. In addition, since it is difficult to distinguish such an improperly corrected stamp from a legitimate stamp, the meaning of inspecting may be lost in a system that simply draws a stamp or a signature.

Therefore, Japanese Patent Application Laid-Open No. 3-220673,
JP-A-3-286374, JP-A-6-4604, JP-A-6-44328, and JP-A-6-681.
In Japanese Patent No. 81 etc., only the stamped portion is image data, which is stored in a database different from the CAD data. When outputting a CAD drawing, the stamped image data is read from the database and combined with the CAD drawing data. There is disclosed a method of confirming the stamp by doing so. According to this method, since the image data of the stamped portion cannot be directly created and corrected from the CAD terminal, it is possible to prevent the unauthorized correction of the stamped portion.

However, from the viewpoint of protecting CAD drawings, it is not sufficient to prevent unauthorized modification of the stamped portion, and the CAD drawing itself is protected by detecting the presence or absence of unauthorized modification of the entire CAD drawing. That is also an important issue. Therefore, key information that changes depending on the contents of the CAD drawing data, such as a checksum method, is generated from the CAD drawing data, and this is stored in a database different from the CAD drawing data, and the There is known a method of detecting an unauthorized correction after drawing by comparing the key information with the key information at the time of detection.

As one of the methods of using such key information, Japanese Patent Laid-Open No. 5-216974 discloses generating key information from CAD drawing data, synthesizing the key information with the stamp image data, and further producing the CAD drawing. Displayed by combining with data,
A method of detecting falsification after printing by printing is disclosed. Further, as a method of protecting word processor document data, Japanese Patent Laid-Open No. 14355/1990 discloses a method of encrypting the seal image data based on key information generated from the document data, and synthesizing the encrypted seal image data with the document data. A method of detecting whether document data has been changed by decrypting the seal image data that was encrypted based on the key information generated from the document data at that time when the document data is displayed and printed. Is disclosed. According to this method, when there is a change in the document data between the time of encryption and the time of decryption, the decrypted seal image is encrypted because the key information has changed between the time of encryption and the time of decryption. It will be restored to a different image than before. Therefore, by comparing the decrypted seal image with the seal image before encryption, it is possible to detect whether or not the document data has been changed. Moreover, this method has the advantage that it is not necessary to store the key information separately from the document data.

[0007]

Although each of the above methods protects drawing data or document data using image data, some CAD systems can only handle vector data. There are many systems that cannot handle CAD, and to add the above-mentioned protection function for drawing information by image data to a CAD system that can handle only vector data,
It is not a practical solution because it requires a major modification of the system itself.

Therefore, as a method of protecting drawing information using vector data widely used in CAD systems, based on the key information generated from the drawing information disclosed in Japanese Patent Laid-Open No. 2-14355. Instead of the method of encrypting the stamp image data, a method of encrypting the stamp vector data based on the key information generated in this way is conceivable. However, in such a method for directly encrypting vector data, when the key information at the time of decryption is changed due to an illegal modification of the drawing, in the process of decrypting the encrypted vector data into the original vector data,
Data that does not conform to the grammar of the CAD system may occur, and it is expected that a grammatical error caused by such data will interrupt processing or cause a system down. Cannot be

In view of the above circumstances, it is an object of the present invention to provide a drawing information protection apparatus capable of detecting an unauthorized modification of a drawing by using vector data.

[0010]

A drawing information protection apparatus of the present invention that achieves the above object extracts key information based on a predetermined rule from drawing information consisting of a plurality of vector data representing a figure. Means, coordinate generation means for generating coordinates on the drawing based on the key information, and graphic information addition means for adding graphic information representing a predetermined graphic arranged at the coordinates to the drawing information. It is characterized by

Here, it is a preferable aspect that the coordinate generating means generates the coordinates to be superimposed on the figure represented by the drawing information on the drawing based on the key information. In addition, the graphic information adding means,
It is also a preferable aspect that the upper graphic information is added with the same display attribute as the display attribute representing the background of the drawing to the drawing information.

[0012]

The drawing information protection apparatus of the present invention, as described above,
An image is created because the coordinates on the drawing are generated based on the key information extracted from the drawing information consisting of multiple vector data, and the graphic information representing the graphic placed at this coordinate is added to the original drawing information. Drawing information can be protected only by vector data without using data.

Here, as the graphic information, for example, by adding vector data of zero length to the drawing information, whether the drawing is displayed on the image display device or printed by the printing device is visually checked. The graphic information can be made unrecognizable. Also, when the coordinates to be superimposed on the figure represented by the drawing information are generated based on the key information, the figure represented by the figure information is superimposed on the frame line of the drawing frame, for example. Thus, the key information can be made unrecognizable.

Further, when the graphic information is added to the drawing information with the same display attribute as the background attribute of the drawing, the drawing is displayed on the image display device or the drawing is printed by the printing device. , It is possible to make the key information unrecognizable.

[0015]

EXAMPLES Examples of the present invention will be described below. FIG. 1 is a system configuration diagram of a CAD system including a first embodiment of the present invention. The CAD system shown in FIG. 1 is a system in which an encryption / decryption device, which is the first embodiment of the drawing information protection device of the present invention, is connected to a normal CAD system, and is a normal CAD system. In addition to the design / drafting process of FIG. 1, protection of drawing information, cancellation of protection of drawing information, comparison of drawing information, and the like can be performed.

As shown in FIG. 1, a CAD system 100
Is a central control device 101, a storage device 102, an input / output device 103, a communication control device 104, and drawing and correction of drawings,
It is composed of a plurality of CAD terminals 105 that perform operations such as output. CAD system 100 configured in this way
An encryption / decryption device 200, which is a first embodiment of the drawing information protection device of the present invention, is connected to the.

The encryption / decryption device 200 includes a processing control means 201 for controlling the processing of each means of the encryption / decryption device 200, and a key generation means 202 for generating a key from the drawing information of the CAD system 100. , A coordinate generation means 20 for generating coordinates on the drawing based on the generated key.
3 and vector data of zero length, which represents a point on the drawing from the coordinates (hereinafter, referred to as "key point data").
The key point data corresponds to an example of graphic information according to the present invention. ) Generating key point data generating means 204,
A synthesizing means 2 for synthesizing the key point data with the drawing information.
05, key point data extraction means 206 for extracting key point data from the drawing information, key restoration means 207 for restoring the original key from the extracted key point data, and restored key and key generation means 202 The key comparison means 208 for comparing the generated key and the processing result of the encryption processing and the decryption processing in accordance with the request from the processing control means 201 are CAD.
It is provided with an output control means 209 for sending to the central control unit 101 of the system 100 and requesting it to perform necessary input / output processing, and a drawing information storage means 210 for storing drawing information.

Of the respective means constituting the encryption / decryption device 200, the key generation means 202 and the coordinate generation means 20
3, key point data generating means 204, and synthesizing means 205
Is a means for encryption, and the key point data extraction means 2
06, the key restoration means 207, and the key comparison means 208 are means for decryption. Further, the processing control means 20
1, output control means 209, and drawing information storage means 210
Is a common means for encryption and decryption.

FIG. 2 is a block diagram showing the encryption / decryption of the first embodiment of the present invention.
3 is a functional relationship diagram of each unit of the decoding device 200. FIG. Less than,
An outline of the function of each unit of the encryption / decryption device 200 will be described with reference to FIG. The processing control means 201 operates as shown below based on each command 110 for protection of drawing information, cancellation of protection of drawing information, and comparison of drawing information from the central control unit 101 (see FIG. 1). To control.

The key generation means 202 is the processing control means 20.
The drawing information 211 is read from the drawing information storage unit 210 in response to a command from the controller 1, and a key is generated from all or part of the drawing information 211 based on a predetermined rule and sent to the coordinate generation unit 203. As a key generation rule in this embodiment, the data of the drawing information 211 for which a key is to be created is divided into a plurality of data strings having a fixed length, and the data string is subjected to predetermined arithmetic processing to calculate a total value. The checksum method is used.

The coordinate generating means 203 generates one or more pairs of numerical values (coordinates) by a predetermined method based on the received key. FIG. 3 is a diagram showing an example of an operation for generating coordinates based on a key. In FIG. 3, the checksum method is used to generate a part of the drawing information 211.
A 10-digit hexadecimal key (a) is shown. 10 binary numbers (b) each consisting of 4 bits
It is expanded to, and these are connected together to make one 40-bit 2
After the base number, this is divided into four 10-bit binary numbers. Next, order information indicating the arrangement order of the keys when decrypting the keys is added to these four binary numbers (c). That is, the ordinal numbers' 0 ',' 1 ',' 2 ','
3 ', each 6-bit sequence information 00 converted into a binary number
000000001, 1,000,01011
Is prepared (d), and this is added to the end of each of the above four binary numbers (c) to generate four binary numbers (e) each having 16 bits. Next, these four 16-bit numbers are divided into eight 8-bit binary numbers (f), these eight 8-bit binary numbers are converted into decimal numbers, and two numbers from the beginning are combined. 4 sets of numerical values (g), that is, (94,128), (14,65), (182,1
94) and (19, 67) are generated. These four sets of numerical values (g) are sent to the key point data generation means 204 as four sets of X and Y coordinates.

The above-mentioned coordinate generation rule is set on the basis of the maximum coordinate value of the drawing in this CAD system, the number of coordinate sets to be divided, and the like. For example, the four sets of X coordinates 94, 14, 182, 19 in FIG. 3 are all within the range of the X coordinate of the target drawing, and the Y coordinates 128, 65, 19
All 4, 67 are also within the range of the Y coordinate of the target drawing.

In order to improve the security of the drawing information, it is desirable to set a rule so that the coordinates after generation have no regularity. Key point data generation means 20 of FIG.
In accordance with the grammar of the CAD system, 4 generates key point data arranged at the above coordinates and sends it to the synthesizing means 205. The synthesizing means 205 synthesizes the received key point data with the original drawing information 211 to obtain the key point data and the drawing information 21.
1 is stored in the drawing information storage means 210.

FIG. 4 is a diagram showing another example of an operation for generating coordinates based on a key. In FIG. 4, as in FIG.
The key (a) represented by 10 digits in hexadecimal is shown. This is divided into 10 binary numbers (b), each of 4 bits. Next, order information indicating the arrangement order of keys when decrypting the keys is added. Ie, ordinal number '
0-, '1', '2', '3', '4', ... Each 4-bit sequence information 0000, 00
01, 0010, 0011, ... (c) are prepared and added to the end of each of the 10 binary numbers (b) to make 10 binary numbers (d) each having 8 bits.
Furthermore, the decimal numbers 96, 225, 130, 51, ...
.. (e) is converted and used as the X coordinate. On the other hand, as the Y coordinate, the y value (y = 23) of one side of the two sides of the frame line 400 of the original CAD drawing parallel to the y axis is used. In the case of this example, it is necessary to adjust the generation rule so that the generated X coordinate falls within the range of the X coordinate of the frame line of the drawing.

As in the above example, the existence of the key itself is recognized by converting the key into the key point data which is superimposed on the drawing on the figure represented by the original drawing information, that is, the point on the frame line, for example. You can prevent it.
In this embodiment, the description will be continued assuming that the key point data is generated by the operation method described with reference to FIG.

Next, the decryption of the key generated from the drawing information, encrypted, and stored in the drawing information will be described. The key point data extraction means 206 of FIG. 2 extracts key point data from the drawing information 213 in the drawing information storage means 210 in accordance with a command from the process control means 201 and sends it to the key restoration means 207.

Further, the key point data extracting means 206 is
A function of deleting key point data from the drawing information 213 in the drawing information storage unit 210 in accordance with a command from the processing control unit 201, and drawing information in the drawing information storage unit 210 in response to an inquiry from the processing control unit 201. A function of detecting whether or not key point data exists in 213 is also provided.

The key restoring means 207 restores the coordinates from the key point data received from the key point data extracting means 206, restores the original key from the coordinates and sends it to the key comparing means 208. FIG. 5 is a diagram showing an example of an operation for restoring a key from coordinates. As shown in FIG. 5, four sets of extracted coordinates (a), that is, (14, 65), (1
9,67), (94,128), (182,194)
Is an 8-bit binary number (b) for both X and Y coordinates
Convert to. Next, the binary number is divided into 16 bits to obtain four 16-bit binary numbers (c). Next, a binary number 0000010000000011, 0 indicating the arrangement order of keys from the lower 6 bits of these 16-bit binary numbers.
000000000010 is taken out, this is converted into a decimal number, and four pieces of order information 1, 3, 0, 2 (d) are taken out. Next, the upper 10 bits of the above 16-bit binary number (c)
The four bits are taken out and rearranged according to the order information (d) to obtain four 10-bit binary numbers (e). next,
After this is made into a 4-bit binary number (f), each of these 4-bit binary numbers is converted into a hexadecimal number and restored to a 10-digit key (g).

The key comparing means 208 in FIG. 2 has the original key (first key) restored by the key restoring means 207,
The key generation means 202 causes the drawing information 213 at that point in time.
Is compared with the key (second key) directly generated from, and the comparison result is sent to the processing control means 201. The processing control means 201 compares the first key and the second key and, as a result, determines whether or not an unauthorized modification has been made.

The output control means 209 is the processing control means 20.
1 determines that an unauthorized modification has been made, the central control unit 101 is requested to notify the concerned parties of the determination result, delete key point data in the stamped area, and prohibit output.
Send to. The central control device 101 controls the input / output device 103 and other peripheral devices based on these requests. The output control means 209 also provides the central controller 10 with information such as the system status of the encryption / decryption device 200 and error information.
Output to 1.

Next, the encryption / decryption device 20 of this embodiment
A flow of processing when the drawing information is protected by using 0 will be described with reference to FIG. (1). The processing control means 201 is a central control device 101.
Command 110 for protection of drawing information 211 from (see FIG. 1)
Upon receiving a, the key point data extraction unit 206 is inquired whether or not the drawing information 211 has key point data.

(2). When the drawing information 211 has key point data, the processing control means 201 draws the drawing information 2
Notifying the output control means 209 that 11 has been protected,
The output control means 209 outputs the corresponding information and ends the process. On the other hand, when the drawing information 211 does not have key point data, the processing control unit 201 requests the key generation unit 202 to generate a key.

(3). The key generation means 202 generates a key from the drawing information 211 and sends it to the coordinate generation means 203. (4). The coordinate generation means 203 generates coordinates based on the received key and sends it to the key point data generation means 204. (5). The key point data generating means 204 generates key point data from the received coordinates and sends it to the synthesizing means 205.

(6). The synthesizing unit 205 synthesizes the received key point data with the drawing information 212, and stores the synthesized drawing information in the drawing information storage unit 210. In this way, the coordinates are generated based on the key generated from the drawing information and stored as key point data together with the drawing information.
The key saved with the drawing information does not change by simply tampering with the drawing, so the original drawing information can be reliably protected by detecting whether the drawing has been tampered with after the key was saved. can do. That is, while extracting the key point data from the drawing information and restoring it to the original key, the key generation means 202 directly generates the key from the drawing information at the time of detection, and the original key and the key at the time of detection are generated. It is possible to detect the presence or absence of tampering by comparing with each other and checking whether the two match.

The original drawing information itself is changed by extracting the key from the drawing information, generating the coordinates, and synthesizing the key point data and the drawing information. Therefore, when comparing the keys,
It is necessary to correct the change in the drawing information itself. Details of the process of extracting the key point data from the drawing information and restoring it to the original key will be described later. In this way, the drawing information protected by the key cannot be properly corrected unless the protection is released. Therefore, the encryption / decryption device 2 must be used to correct the drawing information.
00, it is necessary to cancel the protection of the drawing information.

Hereinafter, with reference to FIG. 2, description will be made on the processing for canceling the protection of the drawing information by using the encryption / decryption device 200 of the present embodiment. (1). The processing control means 201 is a central control device 101.
When the command 110b for canceling the protection of the drawing information 213 (see FIG. 1) is received, the key point data extracting unit 206 is inquired whether the drawing information 213 has the key point data.

(2). When the processing control means 201 receives a response from the key point data extraction means 206 that the drawing information 213 does not have key point data, it notifies the output control means 209 that the drawing information 213 is not in a protected state. Then, the output control means 209 outputs the information corresponding to the output and ends the processing. On the other hand, when the drawing information 213 has key point data, the processing control unit 201 requests the key point data extraction unit 206 to delete the key point data.

(3). The key point data extraction means 206
The key point data is deleted from the drawing information 213, and the drawing information 213 after the key point data is deleted is the drawing information storage unit 2.
Save to 10. In this way, the protection of the drawing information is released, and subsequent corrective modification of the drawing information becomes possible.

Next, with reference to FIG. 2, a process for comparing drawing information by using the encryption / decryption device 200 of this embodiment will be described. (1). The processing control means 201 is a central control device 101.
(See FIG. 1) to command 110c for comparing drawing information 213
When the key information is received, the key point data extraction unit 206 is inquired whether the drawing information 213 has key point data.

(2). When the drawing information 213 does not have the key point data, the processing control means 201 notifies the output control means 209 that the drawing information 213 is not in the protection state, and the output control means 209 outputs the corresponding information. Then, the process ends. On the other hand, when the drawing information 213 has key point data, the processing control unit 201 requests the key point data extraction unit 206 to extract the key point data.

(3). The key point data extraction means 206
The key point data in the drawing information 213 is extracted and sent to the key restoration means 207. (4). The key restoration means 207 restores the coordinates from the received key point data and sends the coordinates to the processing control means 201. (5). On the other hand, the process control unit 201 is configured to draw the drawing information 213.
The key generation means 202 is requested to generate a key from.

(6). The key generation means 202 generates a key from the drawing information 213 and sends it to the processing control means 201. (7). The processing control means 201 sends the key received from the key restoration means 207 and the key received from the key generation means 202 to the key comparison means 208 to request a comparison of these two keys.

(8). The key comparison means 208 uses these 2
The two keys are compared and the comparison result is sent to the processing control means 201. (9). When these two keys match, the processing control means 201 outputs a notification of normal termination to the output control means 209.
If these two keys are different, the output control means 209 is requested to notify the concerned person of the comparison result, erase the key point data in the stamped area, and prohibit the output.

(10). The output control means 209 outputs the information corresponding to the request from the processing control means 201 to the central control unit 101 (see FIG. 1) of the CAD system.
In this way, the drawing information is compared, and as a result,
It is detected whether or not the drawing information has been illicitly modified, and processing is performed according to the detection result. Next, a second embodiment of the present invention will be described. The second embodiment is
The processing control means 201 of the encryption / decryption device 200 of the first embodiment is added with a multi-region protection function for dividing a drawing into a plurality of regions and separately protecting the drawing information of the plurality of regions. Is.

FIG. 6 is a conceptual diagram showing how drawing information of a plurality of areas is protected in the second embodiment of the present invention. As shown in FIG. 6, in the present embodiment, the drawing 601 to be protected is divided into a drawing main body area 602 and five stamp areas 603 to 607 for stamping and stamping, and drawing information is set for each area. Protect.

First, the key point data extraction means 206 of FIG.
Also, the key restoration unit 207 extracts a key from each drawing information in the drawing body area 602 of the drawing 601 and the five stamp areas 603 to 607. As a result, the 10-digit hexadecimal keys 608 and 609 are extracted from the drawing body area 602 and the stamp area 603. Next, by combining these two keys 608 and 609, a 20-digit 1
A hexadecimal key 610 is obtained. Based on the key 610, the coordinate generation means 203 generates coordinates, the key point data generation means 204 generates key point data, and the synthesis means 205 synthesizes the key point data with the drawing 601 to protect the drawing 601. .

As described above, when the drawing information is protected by the key created by combining a plurality of keys, a certain rule is set so that the combined keys can be easily restored to the original plurality of keys at the time of restoration. Need to be kept. In the present embodiment, a rule is adopted in which all keys are hexadecimal numbers of 10 digits and are restored to the original key by dividing every 10 digits at the time of restoration.

By the way, since the drawing inspection is usually carried out by a plurality of inspection persons, it is necessary to add the function of adding the protection by the inspection by the next inspection person to the drawing after the inspection. . FIG. 7 is a conceptual diagram showing how protection is added by a second person in charge of inspection in the second embodiment of the present invention. This additional protection function is the state of protection of the drawing body up to that point and the stamped area up to that point when the next person in charge of drawing inspects the drawing after the inspection by the person in charge of the previous drawing inspection. It is possible to add protection by stamping the next person in charge of inspection while maintaining the protection state of. This additional protection function is added to the multi-region protection function of the second embodiment of the present invention.

Hereinafter, the processing when additional protection is performed will be described with reference to FIGS. 2, 6 and 7. (1). When the processing control means 201 receives a command for additional protection of drawing information from the central control unit 101, the drawing 60
The key point data extraction unit 206 is inquired whether or not 1 (FIG. 6) has key point data.

(2). Since the drawing 601 (FIG. 6) has key point data, the processing control means 201 requests the key point data extraction means 206 to extract the key point data. If the drawing 601 (FIG. 6) does not have the key point data, the processing control means 201 notifies the output control means 209 that the drawing 601 (FIG. 6) is not in the protection state, and the output control means 209. 209 outputs information corresponding to it and ends the processing.

(3). The key point data extraction means 206
The key point data is extracted from the drawing 601 (FIG. 6) and sent to the key restoring means 207, and the key point data is once deleted from the drawing information 213 and then stored in the drawing information storing means 210. (The original key of the once deleted key point data is finally combined with another key to maintain the protection state up to that point.) (4). The key restoration means 207 restores the original key from the received key point data and restores the restored key 610 (FIG. 6).
Is sent to the processing control means 201.

(5). The processing control unit 201 determines whether or not the second person's stamp area 604 (FIG. 6) is in a protected state, that is, whether the drawing information of the second person's stamp area 604 (FIG. 6) has key point data. To the key point data extraction means 206. Since the drawing information of the stamped area 604 does not have key point data, the processing control means 201
Requests the output control unit 209 to output the fact that the drawing inspection process for the second person is possible. The output control means 209 outputs information prompting the drawing inspection staff to input, and waits for an input from the drawing inspection staff.

If the second stamp area 604 (FIG. 6) is in the protected state, the processing control means 201 requests the output control means 209 to output that the stamp area is in the protected state. The key point data extracted in the above item (3) is combined with the drawing information in which the key point data is deleted to restore the drawing information 213 before the start of processing, and then stored in the drawing information storage means 210. The output control unit 209 outputs a message that the stamping process cannot be performed because the stamping of the second person has already been performed, and the process ends.

(6). The second person in charge of drawing inputs the stamp data into the stamp area 604 based on the information output by the output control means 209. In addition, when inputting the stamp data,
The person in charge of inspection may directly create and input the stamp data on the CAD terminal, may copy and input other stamp data that has already been created, or may be registered in advance in the database or the like. You may call and input the stamp data.

(7). The process control unit 201 requests the key generation unit 202 to generate a key from the second person's stamped area 604 (FIG. 7), and at the same time, restores the original key 610 (key 608 and key 609) restored in the above item (4). Are combined) are sent to the key generation means 202. (8). The key generation unit 202 uses the second person's stamp area 60.
4 (FIG. 7), the key 611 is generated, the key 611 (FIG. 7) and the key 610 are combined, and the combined key 612 (FIG. 7) is sent to the coordinate generation means 203.

(9). The coordinate generation means 203 generates coordinates based on the received key 612 (FIG. 7) and sends it to the key point data generation means 204. (10). The key point data generating means 204 generates key point data from the received coordinates and sends it to the synthesizing means 205. (11). The synthesizing unit 205 synthesizes the received key point data with the drawing 601, and stores the key point data in the drawing information storage unit 210.

In this way, the drawings can be protected by the stamps of a plurality of inspection personnel using a plurality of areas of the drawings. In this case, as a matter of course, in the middle of the process, the key comparing unit 208 appropriately compares the stored key with the drawing information by the key generated from the drawing information by the key generating unit 202 to check each drawing or the like. It is necessary to confirm before that the drawings have not been tampered with.

Next, a third embodiment of the present invention will be described. In the third embodiment, the user authentication for authenticating whether or not the person who is going to perform the drawing inspection is an authorized user by the processing control means 201 of the encryption / decryption device 200 of the first embodiment. It is a function added. FIG. 8 is a conceptual diagram showing the function of user authentication in the third embodiment of the present invention.

As shown in FIG. 8, the user interface 7 is added to the encryption / decryption device 200 of the first embodiment.
01, user authentication means 702, and stamp database 7
03 has been added. Further, the processing control means 20 of FIG.
1 and the key generation means 202 are additionally provided with a function of inputting a personal identification number via the user interface 701 at the time of drawing inspection and a function of incorporating the input personal identification number into a key. In addition, the processing control unit 201 and the user authentication unit 702 have a function of prompting the user to input a personal identification number corresponding to the stamped area to be released when the protection is released, and a key of the drawing information to be released from the protection. A function of extracting the personal identification number incorporated therein and a function of comparing the personal identification number extracted from the drawing information with the personal identification number input by the user are added.

The user interface 701 is an input / output means for the user, and the user interacts with the operation window 704 displayed on the screen of the display device, and the encryption / decryption device 200 through the user interface 701. Exchange information with. The outline of the user authentication process will be described below. First, when a person in charge of inspection inputs a personal identification number (12345) into the operation window 704 and input of the inspection data into the inspection area 713 during inspection, the encryption / decryption device 200 causes the drawing A key 718 is generated from the drawing body area 712 of 711, and a key 719 is generated from the stamp data of the stamp area 713. next,
These two keys are combined, and the personal identification number ("12345" in this example) input by the person in charge of drawing inspection is added to this. The encryption / decryption device 200 generates coordinates based on the key 720 thus created, generates key point data from the coordinates, synthesizes the data with the drawing 711, and stores the combined data in the drawing information storage means.

Thus, by incorporating the personal identification number into the key 720 at the time of drawing inspection, it is possible to authenticate the user who intends to release the protection of this drawing 711 after this point. That is, when the user makes a request for canceling the protection, the encryption / decryption device 200 executes the process shown in FIG.
Key 720 is extracted, and the password corresponding to the area 713 is extracted from the key 720, and the user who is going to release the protection is prompted to input the password through the operation window 705 when the protection is released.

The user authenticating means 702 compares the personal identification number extracted from the key 720 of the drawing 711 with the personal identification number input by the user, and cancels protection depending on whether these two personal identification numbers match. Authenticate if the intended person is an authorized user. If these two personal identification numbers match and it is authenticated that the person trying to release the protection is an authorized user, a message indicating that the protection is to be released is displayed on the operation window 705 when the protection is released. , Waiting for the user to release the protection.

On the other hand, when the above two passwords are different from each other, the user authentication means 702 determines that the operation window 7
A message indicating that the request for canceling the protection is cancelled is displayed on the screen 05 and the processing ends. In this way, it is possible to prohibit the release of protection by users other than the authorized users, and it is possible to further effectively protect the drawing information.

In each of the above embodiments, an example in which the key generation means generates a hexadecimal key using the checksum method has been described, but the key information extraction means of the present invention is only the above example. However, the key information is not limited to the checksum method as long as the key information is extracted from drawing information including a plurality of vector data representing a figure based on a predetermined rule.

In each of the above embodiments, the key point data generating means generates graphic information represented as points on the drawing from the coordinates, and the synthesizing means synthesizes the graphic information which is point data with the drawing information. However, the graphic information adding means of the present invention is not limited to the above example, and based on the coordinates generated from the extracted key information, the drawing information has a predetermined graphic arranged at the coordinates. It suffices to add graphic information that represents, and the graphic information is not limited to point data,
It may be line data or surface data.

Furthermore, in each of the above-described embodiments, an example is shown in which the encryption / decryption device has both the functions of encryption and decryption. However, the encryption without the means for decryption is performed. The device and the decryption device without the means for encryption are separately configured, and the encryption device and the decryption device are operated individually or in combination to protect the drawing information. May be.

[0067]

As described above, according to the drawing information protection apparatus of the present invention, drawing information can be protected only by vector data without using image data. Further, even when the drawing information protection apparatus of the present invention is connected to or incorporated in a CAD system, the C which protects the drawing information without making a drastic change to the CAD system.
An AD system can be constructed.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a CAD system including a first embodiment of the present invention.

FIG. 2 is a functional relationship diagram of the encryption / decryption device of each means of the first exemplary embodiment of the present invention.

FIG. 3 is a diagram showing an example of an operation of generating coordinates based on a key according to the first embodiment of the present invention.

FIG. 4 is a diagram showing another operation example of generating coordinates based on a key in the first embodiment of the present invention.

FIG. 5 is a diagram showing an example of an operation for restoring a key from coordinates in the first embodiment of the present invention.

FIG. 6 is a conceptual diagram showing how drawing information of a plurality of areas is protected in the second embodiment of the present invention.

FIG. 7 is a conceptual diagram showing how protection is added by a second person in charge of inspection in the second embodiment of the present invention.

FIG. 8 is a conceptual diagram showing a user authentication function in the third embodiment of the present invention.

[Explanation of symbols]

100 CAD system 101 Central control unit 102 storage device 103 I / O device 104 communication control device 105 CAD terminal 110 Command 200 encryption / decryption device 201 Processing control means 202 key generation means 203 coordinate generation means 204 key point data generation means 205 Synthetic means 206 Key point data extraction means 207 Key recovery means 208 key comparison means 209 output control means 210 Drawing Information Storage Means 211-213 Drawing information 400 border 601 drawings 602 drawing body area 603 to 607 Stamp area 608-612 key 701 user interface 702 User authentication means 703 Stamp database 704 Operation window for drawing inspection 705 Instruction window for releasing protection 711 drawings 712 Drawing body area 713-717 stamping area

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G06F 17/50 H04N 1/387 JISST file (JOIS)

Claims (6)

(57) [Claims] 1. Key information extracting means for extracting key information based on a predetermined rule from drawing information consisting of a plurality of vector data representing a figure, and coordinate generating means for generating coordinates on the drawing based on the key information. And a graphic information adding means for adding graphic information including vector data representing a predetermined graphic arranged at the coordinates to the drawing information. 2. The drawing information according to claim 1, wherein the coordinate generation means generates coordinates that are superimposed on the figure represented by the drawing information on the drawing based on the key information. Protective device. 3. The graphic information adding means is configured to add the graphic information.
Cannot be visually recognized when displayed or printed
Drawing information protection apparatus according to claim 1, wherein the benzalkonium be added graphic information, such as. 4. The graphic information adding means sets the graphic information.
As a graphic information consisting of zero-length vector data
4. The drawing according to claim 3, characterized in that
Information protection device. 5. The graphic information adding means sets the graphic information.
Is the same as the display attribute indicating the background of the drawing in the graphic information.
Is added to the drawing information with a display attribute of
The drawing information protection apparatus according to claim 3, wherein: 6. Comprised of a plurality of vector data representing a figure
Drawing information storage means for storing the drawing information, and the drawing information.
From the drawing information stored in the information storage means to the prescribed rules
The key information based on the above is extracted to generate the coordinates on the drawing,
An encryption method that adds predetermined graphic information to surface information and encrypts it.
A method for operating a drawing information protection device comprising a step, wherein the encryption means uses key information from input drawing information.
And the coordinates on the drawing based on the extracted key information.
The same as the drawing information generated and input to the key information extracting means.
The predetermined drawing information is placed in the drawing information.
Add graphic information consisting of vector data representing
A method for operating a drawing information protection device, comprising: