JPH08237493A - Facsimile equipment - Google Patents

Abstract

PURPOSE: To transmit ciphered data in a short time without causing hindrance to a normal communication in the case of cryptocommunication. CONSTITUTION: An image read section 23 reads an image on a source document with a highest read line density of the equipment on the transmitter side in cryptocommunication. After the density of the read image data is converted into standard line density of 3.85lines/mm, a ciphering section 12 ciphers the data and the ciphered data are coded at a coding section 13 by the MH(Modified Huffman) coding system. Then the coded data are transformed into those of a size corresponding to the size A4 and stored once in an image storage section 17. When a transmission request comes from the receiver side equipment or a preset designated transmission time comes, the coded data stored in an image storage section 17 are read and sent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile machine, and more particularly to a facsimile machine with a cryptographic communication function.

[0002]

2. Description of the Related Art Generally, in a conventional facsimile apparatus, confidential communication is performed when secret communication is required. In this confidential communication, the address information specifying the address is transmitted together with the image data on the transmission side. And
On the receiving side, the received image data is once stored in the image memory, and the image data stored in the image memory is read and printed out only when the password corresponding to the address information is input.

However, in the confidential communication as described above, there is a problem that the secret is easily leaked when the image data is tapped on the telephone line. In order to deal with such a problem, a facsimile machine with a cryptographic communication function has been conventionally proposed.

That is, in the facsimile apparatus having the encryption communication function, when performing the encryption communication, the image on the original is read and the read image data is encrypted by a predetermined encryption method on the transmission side. Sent. On the other hand, on the receiving side, the received encrypted data is printed out on the recording paper as it is, and then the predetermined decryption information is input and at the same time the encrypted data printed on the recording paper is read by the reading unit. The read encrypted data is decrypted and printed out.
Therefore, by using this facsimile apparatus, even if the transmission data is eavesdropped on the telephone line, the confidentiality of the image data can be protected unless the code is decrypted.

[0005]

However, the encryption process of image data is complicated, and the process takes time. For this reason, in the conventional facsimile apparatus, when transmitting the read image data while encrypting the read image data, the transmission time becomes long, the communication cost increases, and in some cases, normal communication operation is hindered. There was a fear of coming.

The present invention has been made by paying attention to the problems existing in such conventional techniques. It is an object of the present invention to provide a facsimile apparatus capable of transmitting encrypted data in a short time without hindering normal communication operation when performing encrypted communication.

[0007]

In order to achieve the above object, in the invention of a facsimile apparatus according to claim 1, an encryption unit for encrypting transmission data and an encoding device for encoding the encryption data are provided. Means, storage means for storing the coded data thereof, and control means for storing the coded data in the storage means and then transmitting the coded data.

According to a second aspect of the present invention, in the facsimile apparatus according to the first aspect, the control means sets a code for setting the coding method by the coding means to the modified Huffman code method during the encrypted communication of the transmission data. It includes a chemical system setting means.

According to a third aspect of the present invention, in the facsimile apparatus according to the first or second aspect, a reading means for reading an image on a document is provided, and the control means controls the transmission image data read by the reading means. At the time of encrypted communication, the reading linear density setting means for setting the reading linear density by the reading means to the maximum linear density of the apparatus and the line for converting the linear density of the image data read at the maximum linear density to the standard linear density. And a density converting means.

[0010]

[Operation] In the facsimile apparatus according to the first aspect, when the encrypted communication is performed, the transmission data is first encrypted by the encryption unit. Then, this encrypted data is encoded by the encoding means and temporarily stored in the storage means. After that, the control means reads out and transmits the encoded data stored in the storage means. That is, the transmission data is not transmitted while being encrypted, but is stored in the storage unit in a state of being encrypted in advance prior to transmission. Therefore, in actual transmission, the transmission time does not become long due to the encryption process.

In the facsimile apparatus according to the second aspect, at the time of cipher communication, the encoding method by the encoding means is set to the modified Huffman encoding method which is the most versatile in the G3 facsimile apparatus. Therefore, each process of encoding and transmitting encrypted data on the transmitting side and each process of receiving and decoding encoded data on the receiving side should be executed as easily and in a short time as possible based on the modified Huffman coding method. You can Therefore, it can greatly contribute to the shortening of the communication time during the encrypted communication.

In the facsimile apparatus according to the third aspect of the present invention, the line density read by the reading means during cipher communication is
Set to the highest linear density the device has. Then, the linear density of the image data read at the highest linear density is converted into the standard linear density. Therefore, it is possible to reduce the data amount as much as possible while improving the image quality of the read image data as much as possible. Therefore, even during encrypted communication, the time required for actual transmission can be minimized, and the encrypted data received on the receiving side can be decrypted as close as possible to the original image data.

[0013]

Embodiment An embodiment of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, a signal processing unit (CPU) 11 as a control unit that constitutes an encoding method setting unit, a reading linear density setting unit, and a linear density converting unit is for controlling the operation of the entire facsimile apparatus. And the encryption unit 12, the decryption unit 13, and the encoding / decoding unit 1
It is equipped with 4. The encryption unit 12 constitutes an encryption means,
At the time of encrypted communication, the transmission image data is encrypted by a predetermined encryption method. The decryption unit 13 decrypts the received encrypted data during encrypted communication.

The encoding / decoding section 14 constitutes an encoding means, and encodes the transmission image data or the reception image data in order to compress the redundancy of the image data. It should be noted that the encoding / decoding unit 14 uses the encryption unit 1 during encrypted communication.
The image data encrypted in 2 is encoded and the received encoded data in the encrypted state is decrypted. In the present embodiment, the coding / decoding unit 14 uses a modified Huffman coding method (hereinafter, referred to as MH coding method) and a modified read method (hereinafter, MR) as coding methods.
Image data) and image data can be encoded by various encoding methods such as the MMR method.

A ROM (Read Only Memory) 15 stores a program necessary for the operation of the signal processing unit 11.
The RAM (random access memory) 16 includes an image storage unit 17 as a storage unit, and the image storage unit 17 stores the transmission image data and the reception image data in an encoded state. The RAM 16 also stores various other information such as telephone numbers.

The automatic dialer 18 makes a dial transmission when transmitting a facsimile. Line control unit (NCU) 1
Reference numeral 9 controls the connection between the facsimile device and the telephone line.
The modem 20 performs modulation and demodulation of transmitted / received data. The protocol signal generation circuit 21 generates a protocol signal according to a facsimile communication procedure. The protocol signal detection circuit 22 detects a protocol signal transmitted from the other party. The protocol signals generated or detected by these circuits 21 and 22 include a signal for confirming whether the partner device has a required function such as a cryptographic communication function.

The image reading section 23 as a reading means optically reads an image on a document set on a document table. The print output unit 24 prints on recording paper based on the received image data, the image data read by the image reading unit 23, and the like. The operation unit 25 includes an encryption key 26 for selecting an encrypted communication mode and a decryption key 27 that is operated when decrypting the encrypted data obtained by the encrypted communication, and also includes a numeric keypad, a one-touch dial key, a transmission key, etc. Is equipped with.
The display unit 28 including a liquid crystal display or the like is for displaying various kinds of information.

Next, the operation of the facsimile apparatus configured as described above will be described. Now, in the case of performing transmission in the facsimile apparatus of this embodiment, the transmission processing is performed according to the flowchart shown in FIG. 2 under the control of the signal processing unit 11. That is, it is determined whether or not the encryption key 26 of the operation unit 25 is turned on, and when the encryption key 26 is in the off state, the normal transmission operation, that is, the original read by the image reading unit 23 is performed. Image data is transmitted without being encrypted, and the operation is completed after the transmission is completed (steps S1 to S3).

On the other hand, when the encryption key 26 is turned on, the encryption key is input (step S4). The encryption key is a kind of encryption information used in the secret key encryption method, and is shared between the transmission and reception together with a decryption key as decryption information on the receiving side, which will be described later. After that, when the transmission key is turned on while the dial input is made by the operation of the ten-key pad or the one-touch dial key of the operation unit 25, the original reading mode by the image reading unit 23 is set to the highest reading mode of the apparatus. At the same time, the encoding system by the encoding / decoding unit 14 is set to the MH encoding system (steps S5 to S8).

The original reading mode in the facsimile apparatus includes three modes: normal mode, fine mode and super fine mode. Then, in the normal mode, the line density read by the image reading unit 23 is set to the standard line density of 3.85 lines / mm, which is twice the fine line mode in 7.7 lines / mm, and in the super fine mode. 2 more
It is set to double the line density of 15.4 lines / mm.
Therefore, for example, when the highest reading mode of the apparatus is the fine mode, the line density read by the image reading unit 23 is set to 7.7 lines / mm, and in the super fine mode, 15.4 lines / mm. set to mm.
The MH coding system is a standard coding system recommended by the CCITT facsimile which has the highest versatility and can be easily executed in a G3 facsimile apparatus.

Next, the image reading section 23 starts reading the image on the original set on the original table in the set reading mode (step S9). Then, the linear density of the read image data is sequentially converted into the standard linear density (3.85 lines / mm) corresponding to the normal mode (step S10). Then, the linear density converted image data is sequentially converted into encrypted data by the encryption unit 12 based on the encryption key and encrypted (step S1).
1). Next, the encoding / decoding unit 14 encodes the encrypted data by the MH encoding method and compresses the data amount (step S12). Then, this encoded data is A
The image data is converted into a size corresponding to four sizes and stored in the image storage unit 17 of the RAM 16 (step S13). For example, when the size of the read document is B4 size or the like larger than A4 size, the encoded data is reduced, and when the size of the read document is B5 size or the like smaller than A4 size, the encoded data is enlarged and stored in the image storage unit 17. To be done.

After that, it is judged whether or not all the originals set on the original platen have been read and the encoded data has been stored in the image storage unit 17 (step S14).
The operations from step S10 to step S14 are repeatedly performed until they are completed. That is, while the transmission image data is being encrypted and encoded, the transmission image data is not transmitted to the receiving side device but is temporarily encrypted and encoded in the image storage unit 17 before being transmitted. Remembered.

Thereafter, based on a transmission request from the receiving side device or a preset transmission time set in advance, the image storage unit 1
It is determined whether or not the encoded data stored in No. 7 can be started to be transmitted (step S15). Then, when the transmission can be started, the encoded data is read from the image storage unit 17, and the encoded data is transmitted via the modem 20, the line control unit 19 and the telephone line (step S).
16). Then, it is determined whether or not the transmission of this encoded data is completed, and when the transmission is completed, all the operations are completed (step S17).

As described above, when the image data is encrypted and transmitted, the print data is printed on the recording paper by the print output unit 24 in the receiving facsimile apparatus in the same state. Therefore, even if the transmitted image data is eavesdropped from the telephone line, the eavesdropped data is encrypted image data, so that the confidentiality of the image data can be protected unless it is decrypted.

Then, in the facsimile machine on the receiving side, when the encrypted data printed on the recording paper is decrypted, the decryption process is performed according to the flow chart shown in FIG. 3 under the control of the signal processing section 11. That is, when the decryption key 27 of the operation unit 25 is turned on in a state where the recording paper on which the encrypted image data is printed is set on the platen as a read original, the decryption key corresponding to the encryption key on the transmitting side is set. Is input (steps S21 to S23).

After that, the image reading unit 23 starts reading the encrypted image data on the original, and the decoding unit 13 starts decoding the read data (step S24). That is, the read data by the image reading unit 23 is converted from the encrypted data into the normal image data before being encrypted, based on the decryption key. Then, it is determined whether or not the original reading and the decoding processing of the read data are completed, and at the time when they are completed, the print output unit 24 starts the printing of the decoded data on the recording paper (steps S25 to S26). ). After that, it is judged whether or not the printing operation is completed, and when the printing is completed, all the operations are completed (step S27).

As described above, in the facsimile apparatus of this embodiment, when performing the encrypted communication, the transmission side performs the encryption and the encoding of the transmission image data in advance before the actual transmission. Then, at the time of actual transmission, the transmission image data in the already encrypted and encoded state in the image storage unit 17 is only read and transmitted. Therefore, unlike the conventional device which transmits while transmitting and encrypting the transmission image data, it does not take time to encrypt the transmission image data and the transmission time does not become long. For this reason, it is possible to suppress the communication cost at the time of encrypted communication, and there is no fear that the normal communication operation will be hindered.

Further, in the facsimile apparatus of this embodiment, during the encrypted communication, the encrypted data is encoded by the MH encoding method which is the most versatile in the G3 facsimile apparatus and stored in the image storage unit 17. That is, when it is confirmed that the encoding schemes are different between transmission and reception at the start of communication, it is necessary to re-encode the encoded data in the image storage unit 17 using the encoding scheme that matches the receiving side. , MH encoding method, in the present embodiment,
No such need arises. For this reason, the MH performs the processes of encoding and transmitting encrypted data on the transmitting side and the processes of receiving and decoding encoded data on the receiving side.
It can be executed as easily and in a short time as possible based on the coding method. Therefore, it is possible to greatly contribute to the shortening of the communication time at the time of encrypted communication in which the processing of image data is complicated as compared with the normal communication.

Further, in the facsimile apparatus of this embodiment, during cipher communication, the image on the original is read by the image reading unit 23 in the highest reading mode of the apparatus, and then the linear density of the read image data is changed. Converted to a standard linear density of 3.85 lines / mm. Therefore, it is possible to reduce the data amount as much as possible while improving the image quality of the read image data as much as possible. Therefore, even during encrypted communication, each process of encryption, encoding and transmission on the transmission side and each process of reception and decryption on the reception side can be executed in the shortest possible time, and the communication time can be shortened. It can make a big contribution. Moreover, on the receiving side, the received encrypted data can be decrypted as close as possible to the original image data.

In addition, in the facsimile apparatus of this embodiment, when the encrypted data is encoded and stored in the image storage unit 17, the encoded data is converted into a size corresponding to the A4 size and stored. . That is, when it is confirmed that the document size and the recording paper size are different between the transmission and the reception at the start of communication, it is necessary to reduce or enlarge the data in the image storage unit 17 to a size matching the receiving side and transmit the data. Occurs. However, since the A4 size is the most frequently used size as the original on the transmitting side and the recording paper on the receiving side, in the present embodiment in which the encoded data is converted into the A4 size and stored, such a need is almost eliminated. Does not happen. Therefore, each process of reading and transmitting encoded data on the transmitting side, data receiving process on the receiving side, and the like can be executed as easily and in a short time as possible on the basis of A4 size data. Therefore, it can greatly contribute to the shortening of the communication time during the encrypted communication.

The present invention can be modified and embodied as follows. (1) Of the processes of performing linear density conversion after reading a document in the highest reading mode, performing the MH encoding, and converting the encoded data into A4 size during encrypted communication Perform only one or two processes. Even in this case, it is possible to contribute to the shortening of the communication time during the encrypted communication.

(2) When encrypted data is received by the receiving device, it is temporarily stored as confidential information in the image storage section 17 of the RAM 16, and when the decryption key is turned on after that, the encrypted data is read out, Configure to print on recording paper while decrypting.

The technical idea which can be understood from the above-mentioned embodiment will be described below. (1) The control means sets the encoded data to A4 at the time of encrypted communication.
The facsimile apparatus according to any one of claims 1 to 3, wherein the facsimile is converted into a size corresponding to the size and stored in the storage means.

By doing so, it is possible to greatly contribute to the shortening of the communication time during the encrypted communication.

[0035]

EFFECTS OF THE INVENTION Since the present invention is configured as described above, it has the following effects. According to the invention described in claim 1, when the encrypted communication is performed, the transmission side encrypts and encodes the transmission data prior to the actual transmission. Therefore, in the actual transmission, the transmission of the encrypted data is performed. Can be done in a short time. Therefore, it is possible to suppress the communication cost at the time of encrypted communication,
There is no fear of hindering normal communication operation.

According to the invention described in claims 2 and 3, it is possible to greatly contribute to the shortening of the communication time at the time of encrypted communication. In particular, according to the third aspect of the invention, the image quality of the read image data is improved, and it becomes possible for the receiving side to decrypt the received encrypted data as close as possible to the original image data.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a facsimile apparatus of the present invention.

FIG. 2 is a flowchart mainly showing the operation on the transmitting side in the encrypted communication mode.

FIG. 3 is a flowchart showing an operation on the receiving side in the encrypted communication mode.

[Explanation of symbols]

11: a signal processing unit as a control unit that constitutes an encoding method setting unit, a reading linear density setting unit, and a linear density converting unit,
12 ... an encryption unit as an encryption unit, 13 ... a decryption unit,
14 ... Encoding / decoding section as encoding means, 17 ... Image storage section as storage means, 23 ... Image reading section as reading means, 24 ... Print output section, 25 ... Operation section, 26 ... Encryption key, 27 ... Decryption key.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H04N 1/387 101 1/419

Claims (3)

[Claims] 1. An encryption means for encrypting transmission data,
A facsimile apparatus comprising: an encoding unit that encodes the encrypted data; a storage unit that stores the encoded data; and a control unit that temporarily stores the encoded data in the storage unit and then transmits the encoded data. 2. The facsimile apparatus according to claim 1, wherein the control unit includes a coding system setting unit that sets a coding system by the coding unit to a modified Huffman coding system during encrypted communication of transmission data. 3. A reading unit for reading an image on an original is provided, and the control unit has a maximum linear density of the reading linear density of the reading unit when the transmission image data read by the reading unit is encrypted. The facsimile apparatus according to claim 1 or 2, further comprising: a reading linear density setting means for setting the reading linear density setting means; and a linear density converting means for converting the linear density of the image data read at the maximum linear density into the standard linear density.