JP2003281063A - E-mail communication equipment and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit e-mail that cannot be transmitted because of the limitation of a file size. <P>SOLUTION: A mail main body and an attached file are inputted from a data inputting part 10 and sent to an e-mail transmission part 12 through a data size reducing part 11. The data inputted from the data inputting part 10 are also sent to a total size calculating part 13, which calculates the total size as e-mail. A comparing part 15 compares the total size with an upper limit set by a upper limit setting part 14. The data size reducing part 11 reduces the data on the basis of the comparison results of the comparing part 15 such that the total size does not exceed the upper limit. A destination inputting part 16 sends an e-mail address to the e-mail transmission part 12. The e-mail transmission part 12 transmits the data which are transmitted through the data size reducing part 11 and do not exceed the upper limit as e-mail to the destination designated by the e-mail address. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic mail communication technique, and more particularly to preventing electronic mail of a data size that a receiving terminal cannot receive.

[0002]

2. Description of the Related Art In recent years, LAN (Local Area)
E-mail using the Internet or the Internet is widely used. In addition to simple texts, electronic mails can be sent with various files such as data files such as images and voices and executable files attached. By the way, an electronic mail system is often provided with an upper limit on the data size of a file sent by electronic mail in a mail server so as not to place an excessive load on a server or a network. for that reason,
If you send an email that exceeds the upper limit, an error email is usually returned from the mail server and the email does not reach the other party.

As a conventional means for solving these problems, as disclosed in Japanese Patent Laid-Open No. 2001-282865, it has a function of processing image information in page units and divides transmission image information into page units, It has been proposed that the divided image information be transmitted using a plurality of electronic mails, and that the mail be added with divided information for reconstructing the divided images.

However, this method requires the receiving side to have dedicated software for recombining a plurality of divided mails. Also, because the mail is divided into multiple mails, the total data size is increasing,
The load on the network is not always reduced. In addition, the capacity of the mailbox of the recipient's mail server and the capacity of the storage medium of the recipient's terminal will be put more pressure.

Furthermore, if either the sender or the receiver is in a dial-up connection, a packet mode, or the like, a charge is charged according to the communication time and the data size, which causes an additional communication charge. there were.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above circumstances, and it is an object of the present invention to prevent a receiving side from sending a mail having a data size that cannot be received.

[0007]

According to the present invention, in order to achieve the above-mentioned object, the structure as described in the claims is adopted. Here, before describing the invention in detail, the description of the claims will be supplementarily described.

[0008] That is, according to one aspect of the present invention, in order to achieve the above object, the electronic mail communication device includes: means for calculating a data size of an electronic mail including image data; When exceeds a predetermined upper limit value, an image data size reducing means for reducing the data size of the image data until the data size of the electronic mail does not exceed the upper limit value.
A mail transmitting means for transmitting an electronic mail whose data size does not exceed a predetermined upper limit value to a predetermined destination is provided.

In this structure, the data size of the electronic mail can be adjusted prior to the transmission, so that the electronic mail can be reliably transmitted to the receiving terminal.

The electronic mail communication device also functions as a mail user agent device operating on a client device.
Alternatively, it can be configured as a mail transfer agent device operating on the server device.

According to another aspect of the present invention, in order to achieve the above-mentioned object, a means for transmitting an electronic mail including image data to an electronic mail communication device; and a data size of the transmitted electronic mail. Means for receiving error information indicating that transmission has failed due to a large error; image data size reducing means for reducing the data size of the image data when the error information is received; and image data for reducing the data size. And means for sending e-mails including.

With this configuration, when the data size of the electronic mail is large and the transmission is rejected, the data size is adjusted afterwards and the electronic mail is retransmitted.
Similarly, the electronic mail can be reliably transmitted to the receiving terminal.

The electronic mail communication device having the mail user agent function may be a computer (personal computer), a mobile phone, a PDA (personal digital assistant), or the like. Further, the present invention can be applied not only to electronic mail but also to the field of transmitting electronic (image) files by communication such as file transmission between a PC and a printer.

The present invention can be realized not only as an apparatus or system, but also as a method. Further, it goes without saying that a part of such an invention can be configured as software. Further, it goes without saying that a software product used for causing a computer to execute such software is also included in the technical scope of the present invention.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An electronic mail communication device according to an embodiment of the present invention will be described below.

First, a network environment in which this embodiment is used will be described. FIG. 1 shows this network environment. In this figure, a LAN network 100 is shown.
a, 100b, 100c are connected to the Internet 101. LAN networks 100a, 100b,
100c includes a DNS (Domain Name System) server 102a, 102b, 102c and a mail server (SMT).
P server, POP server) 103a, 103b, 103
c is provided. Mail server 103a, 103
b and 103c hold spools (mailboxes) for storing the electronic mails sent to the accounts.
In addition, LAN networks 100a, 100b, 100
In c, an electronic mail communication device (which may be simply called a terminal, a transmission terminal, or a reception terminal) 104a, 104 which is a client device of the mail server 103a, 103b, 103c
b and 104c are arranged. The client device (e-mail communication device 104) does not need to have an account of the mail server 103 in the LAN network 100 to which it belongs, but this is done for convenience of explanation. Also,
In this example, the electronic mail communication device 104d is the public network 105.
Also, it is connected to the LAN network 100c via the access server 106 and makes a mail transmission / reception request to the mail server 103c. Each LAN network 1
00a, 100b, 100c are routers 107a, 107
It is connected to the Internet 101 by b and 107c.

For example, the electronic mail communication device 104a is
Have an account on the mail server 103a and take out an e-mail from the spool of the mail server 103a. To send an e-mail from the e-mail communication device 104a to another terminal, for example, the e-mail communication device 104c, the mail server 103a is requested to send the e-mail. This e-mail is sent to the mail server 103c directly or via one or more relay mail servers, and the e-mail communication device 104c receives the e-mail from the spool of the mail server 103c.

The electronic mail transfer procedure will be further described by taking an example of Internet mail. To send an email: Note that the terminal and the server are represented by (A) and (B) for convenience. Send from the sending terminal (A) to the mail server (A). The mail server (A) refers to the address resolution information of the DNS server (A) on the network to check the delivery destination, and when specified, sends the mail to the mail server (B). The mail server (B) sorts the received mail into individual posts (spools) in its own server. The receiving terminal (B) takes out the mail from its spool in the mail server (B).

Here, the mail server is often set with a file size upper limit (usually about 1 to 2 M bytes) so as not to put a load on the network. If the sending terminal sends a mail with a size exceeding the upper limit, the mail server returns an error mail to the sender and does not deliver the mail to the receiving terminal. When addressed to a mailing list server, error mail is sent to the mailing list administrator, not the sender.

Also, the upper limit of the total capacity size is usually set in the individual spool area of the mail server (B), and when a new incoming mail exceeding the size is received,
Processing such as deleting old mail, refusing to accept new mail, and truncating new mail is performed.

Further, depending on the receiving terminal, the total capacity may be limited due to the restriction of the storage area, and the same processing as the mail server (B) is performed (portable terminal etc.).

As described above, depending on the file size of the transmitted mail, the mail may not reach the other party normally.

In this embodiment, the structure described below is adopted to prevent such a problem.

Next, the electronic mail communication device 1 of this embodiment
A hardware configuration example 04 will be described in detail.

FIG. 2 shows a hardware configuration example of the electronic mail communication device 104. In this figure, the electronic mail communication device 104 includes a CPU 201 and a storage device 202.
(Including ROM 203 and RAM 204), input unit 2
05, a display unit 206, an image processing unit 207, a net control unit 208, a system bus 209, and the like.

The electronic mail communication device 104 is connected via the Internet or the net control unit 208.

The CPU 201 is an electronic mail communication device 10
4 is a control unit for controlling the whole. CP in ROM203
A program executed in U201, various data, a data size upper limit setting value, a mail address book, and the like are stored. The RAM 204 stores the data size calculation result of the transmission file and the like. It is also used as a work area during program execution. The storage device 202 includes an auxiliary storage device such as a hard disk in addition to the ROM 203 and the RAM 204, and stores and expands files.

The image processing section 207 is a section for performing various image processing such as image resolution conversion, compression, gradation conversion, and color number reduction, and is composed of hardware or software programs.

The input unit 205 is an input device such as a keyboard and a mouse for inputting mails and mail addresses. The display unit 206 is a CRT, a liquid crystal display, or the like, and may also have an input function such as a touch panel.

An example of transmitting an image will be shown. The input unit 205 is used to input a destination, mail data, and attach a file. If there is an attached file, it is determined whether it is an image file or a general data file. In addition, the total size of the attached mail and the body of the mail is calculated, and the size is compared with a preset upper limit size value. If the sent mail size does not exceed the set size, proceed to. If it exceeds the set size, reduce the data size appropriately according to the format of the attached file, and reduce the size to the set size or less. It is transmitted to the network through the net control unit 208.

Next, the electronic mail communication device 1 of this embodiment
The main part 04 will be described.

FIG. 3 schematically shows the functions of the main parts of the electronic mail communication device 104 of this embodiment. In FIG. 3, the data input unit 10 (corresponding to the input unit 205 of FIG. 2) sends a mail. Data (mail body) and attached files are input and sent to the electronic mail transmission unit 12 via the data size reduction unit 11. The data size reduction unit 11 reduces attached files as needed.

The data input from the data input unit 10 is also sent to the total size calculation unit 13 where the total size as an electronic mail is calculated. This total size is compared with the upper limit value set by the upper limit value setting unit 14 in the comparison unit 15. The data size reduction unit 11 reduces the data based on the comparison result of the comparison unit 15 so that the total size does not exceed the upper limit value.

The destination input unit 16 (corresponding to the input unit 205 in FIG. 2) receives a registered name, a registered electronic mail, etc. as destination data, and if necessary, refers to the address book storage unit 17 to send an electronic mail address. Is taken out and sent to the electronic mail transmission unit 12. The electronic mail transmission unit 12 transmits, as an electronic mail, the data sent via the data size reduction unit 11 to the destination (spool of the mail server) specified by this electronic mail address, the data not exceeding the upper limit value. To do.

The address book storage unit 17 stores information about the upper limit value and data size reduction method for each destination, as will be described later.

An error mail (reception refusal) sent from the mail server is received by the mail receiving unit 18 and sent to the error mail processing unit 19. The error mail processing unit 19 analyzes the error mail, detects the upper limit value defined by the mail server, requests the data size reduction unit 11 to reduce the data size, and instructs the electronic mail transmission unit 12 to resend the electronic mail. To do. The upper limit value detected by the error mail processing unit 19 is stored in the address book storage unit 17 as the upper limit value of the corresponding destination.

Next, a data reduction method will be described. The files attached to the mail can be roughly classified into data files such as documents and programs and image files created by a digital camera, retouching software, or the like.

A data file, for example, a file created by Word or the like, often has a small file size by applying compression such as LZH or ZIP.

Further, since the image file is a non-compressed file format such as a bitmap file (BMP), the size of the image file can be reduced by LZH or ZIP compression as with the data file. If the file is a 256-color image file, for example, the file size can be reduced by changing it to 16 colors or monochrome (reducing the number of colors). Furthermore, the file size can be reduced by changing the image format to a compression format such as JPEG. There is also a format such as JPEG in which the compression rate can be freely set. TIFF has multiple compression formats, CCIT
T Group3 / Group4, Graysca
le, LZW, etc. can be selected.

As described above, the file size can be reduced by compressing the attached file.

In the case of a data file, it is necessary to match the original state when decompressing, so the lossless compression method is used. In the case of an image file, lossless compression is desirable, but there is a limit to compression efficiency, and lossy compression such as JPEG is also widely used.

What method is used to reduce the file size depends on the environment of the other party, how the file is used, and the like.
For example, if a file format that is not commonly used is used, it is more likely that the other party cannot open the file. Further, when the sent image is reused, it is desirable to adopt a lossless compression method so that the original image can be reproduced. If the partner terminal is a facsimile or the like and can print in black and white, sending a color image is meaningless.

As described above, it is necessary to adopt an appropriate method for reducing the file size.

Next, the operation of the embodiment will be described.

FIG. 4 illustrates an example in which data is adjusted so as not to exceed the set upper limit value and then sent as an electronic mail. In this figure, after the mail is created,
The total size of the email body and the attached file is calculated and compared with the transmission upper limit size setting value (S10, S11).
If the total size does not exceed the set value, the e-mail is sent as it is (S12, S13). If the total size exceeds the set value, it is determined whether there is an attached file (S14). If there is no attached file, only the text is present, so it is determined that there is no data size reduction means and transmission is stopped (S15, S16). If there is an attached file, the procedure moves to the procedure for reducing the size (after step S17). It is determined whether the attached file is an image file (S1
7) If it is not an image file, it is regarded as a data file and a data compression process (plural types) such as LZH is tried (S18, S19). If it is an image file, the image format is discriminated and data size reduction processing (a plurality of data files are possible) is performed according to the format (S21, S22).

After the data size reduction processing is completed, the total size of the mail body is calculated and re-compared with the set value (S22). The method of various data reduction processing, the size after reduction, and the comparison result with the set value are listed and displayed on the screen (S23). A display example is as shown in FIG. 5, for example.

If the upper limit value is exceeded in all the processes, a message of size over / transmission disabled is displayed and the process proceeds to the transmission stop process (S24, S15, S16). If not, the sender is made to select from the list of size reduction methods displayed, and the file is attached to the mail by the method of the selection result and sent (S25, S26, S13).

In the example of the list of calculation / comparison results shown in FIG. 5, "TIFF conversion", "JPEG conversion", "P
Three compression modes are shown for each of the "ng conversion". Those that exceed the upper limit value (for example, 500 Kbytes) are darkly masked, and those that do not exceed the upper limit value are displayed brightly.

Even if the data is compressed, the upper limit value is exceeded, so when the transmission is stopped, a message as shown in FIG. 6 is displayed. Further, when the sender's permission is obtained when compressing and transmitting the data, a message as shown in FIG. 7 is displayed. Furthermore, when the data is compressed and transmitted, a notification as shown in FIG. 8 may be performed afterwards.

Next, an example in which the size of the attached file is reduced when a size error mail is returned will be described. FIG. 9 shows the operation at this time. In this figure, if an error mail is sent as a result of mail transmission, the content of the mail is analyzed to determine whether the cause of the error is oversize (S30, S31). , S3
2). If the cause of the error was not oversize,
This is another process (S33). For example, the administrator is notified. Of course you don't have to do anything. If it is analyzed that the cause of the error is oversize, the size of the sent mail (text + attached file) is calculated (S3).
4). It is determined whether or not the value of the upper limit size is written in the error mail (S35), and if there is such information, the upper limit of the size of the transmitted mail is set based on that information (S36).
If no information is found, a specific upper limit size is set (S37). However, in this case, the value should be set smaller than the size of the sent email that caused an error. It is determined whether or not the mail has an attachment file (S38), and if there is no attachment file, the sender is notified with a message not to be sent again, and the processing ends (S38).
39, S40). If there is an attached file, the attached file size reduction processing is performed in the same manner as in FIG. 4 (S41).

Next, a method of setting the transmission size of the own terminal based on the transmission mail limit size of the mail server will be described. FIG. 10 shows an example of the error mail (mail from the mail server). As shown in this figure, the subject (“Subject:” is “Message too”).
long (> 1,000,000) ”. From this, it can be seen that the upper limit of the data size set in the mail server is 1 Mbyte. This information is analyzed to set the maximum size of outgoing mail.

Next, a method of setting the transmission size of the own terminal and the type of means for reducing the size for each destination will be described.

As shown in FIG. 11, the destination and the transmission upper limit size are related by a table. The upper limit size may be set based on the mailbox capacity of the receiving mail server of the partner or the mailbox capacity of the partner terminal. Furthermore, by registering the convertible format in association with the destination, it is possible to prevent the other party from sending a file that cannot be processed.

The present invention is not limited to the above-described embodiments, but can be variously modified without departing from the spirit thereof.

For example, in the above example, the processing of the electronic mail on the client side has been described, but as shown in FIG. 12, data reduction may be performed on the mail user agent apparatus 300 side (client apparatus side), Data reduction may be performed on the mail transfer agent device 301 side (server side). On the server side, the mail transfer agent device (SMTP server) that first receives the transmission request from the transmission client may reduce the data, or in some cases, the server that provides the POP service or the IMAP service to the receiving terminal may reduce the data. It is also possible to do it. On the server side, it is possible to add settings for data reduction for each account (mail service client). In addition, 302 is a LAN
Or WAN. Further, the present invention can be widely applied to data communication of various protocols.

[0056]

As described above, according to the present invention, it becomes possible to send an electronic mail or the like which could not be sent due to the limitation of the file size. By reducing the size, it is possible to reduce the load on the network, save communication costs and communication time, and effectively use the storage area of the storage medium.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a network environment according to an embodiment of this invention.

FIG. 2 is a diagram illustrating a hardware configuration example of the above-described embodiment.

FIG. 3 is a block diagram schematically showing a function of a main part of the above-described embodiment.

FIG. 4 is a flowchart illustrating an example of operation of the above-described embodiment.

FIG. 5 is a diagram illustrating a list of conversion formats used in the above embodiment.

FIG. 6 is a diagram illustrating an example of a message display used in the above-described embodiment.

FIG. 7 is a diagram illustrating another example of message display used in the above-described embodiment.

FIG. 8 is a diagram illustrating still another example of message display used in the above-described embodiment.

FIG. 9 is a flowchart illustrating another example of the operation of the above embodiment.

FIG. 10 is a diagram illustrating an error mail used in the above embodiment.

FIG. 11 is a diagram illustrating a table used in the above embodiment.

FIG. 12 is a diagram illustrating a modified example of the above-described embodiment.

[Explanation of symbols]

10 Data input section 11 Data size reduction unit 12 E-mail sender 13 Total size calculator 14 Upper limit value setting section 15 Comparison section 16 Destination input section 17 Address book storage 18 Email Receiver 19 Error mail processing section 100 networks 101 Internet 102 DNS server 103 mail server 104 E-mail communication device 105 public network 106 access server 107 router 202 storage device 203 ROM 204 RAM 205 Input section 206 display 207 Image processing unit 208 Net control unit 209 system bus 209 Image processing unit 300 mail user agent device 301 Mail transfer agent device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kentaro Fukami             Fujize, 3-7-1, Fuchu, Iwatsuki City, Saitama Prefecture             Rocks Co., Ltd. Iwatsuki Office F-term (reference) 5C078 CA02 CA34 DA01 EA01

Claims (20)

[Claims] 1. A means for calculating a data size of an electronic mail including image data, and when the data size of the electronic mail exceeds a predetermined upper limit value, the data size of the electronic mail exceeds the upper limit value. Until it does not exist, it has an image data size reducing means for reducing the data size of the image data and a mail sending means for sending an electronic mail whose data size does not exceed a predetermined upper limit value to a predetermined destination. Characteristic e-mail communication device. 2. The electronic mail communication device according to claim 1, further comprising means for setting the predetermined upper limit value. 3. The image data size reduction means includes at least resolution conversion, compression, compression ratio change, compression method change, gradation reduction of multi-valued images, color number reduction of color images, and black-and-white conversion from color images. Claim 1 or 2 which is one
E-mail communication device described. 4. The electronic mail communication device according to claim 1, 2 or 3, wherein the upper limit of the data size is determined on the basis of the limit size per electronic mail in the mail server. 5. The electronic mail communication device according to claim 1, 2 or 3, wherein the upper limit of the data size is determined according to the destination of the electronic mail. 6. A means for transmitting an electronic mail including image data, a means for receiving error information indicating that transmission of the electronic mail has failed due to a large data size, and a means for receiving the error information. An electronic mail communication device comprising: an image data size reducing means for reducing the data size of the image data; and a means for transmitting an electronic mail including the image data with the reduced data size. 7. The image data size reduction means includes at least resolution conversion, compression, compression rate change, compression method change, gradation reduction of multi-valued images, color number reduction of color images, and black-and-white conversion from color images. 7. The electronic mail communication device according to claim 6, which is one. 8. The reduction method used by the image data size reduction means can be set for each destination.
The electronic mail communication device according to any one of 1. 9. The e-mail communication device according to claim 1, wherein after the e-mail is transmitted after reducing the data size of the image data, the destination is notified of the message of the size change. 10. A method for notifying a sender of a message confirming permission of size conversion when sending an e-mail with a reduced data size of image data.
9. The electronic mail communication device according to any one of 9. 11. A step of calculating a data size of an electronic mail including image data; and, when the data size of the electronic mail exceeds a predetermined upper limit value, the data size of the electronic mail exceeds the upper limit value. Until there is no more, the image data size reduction step of reducing the data size of the image data, and a mail transmission step of transmitting an email whose data size does not exceed a predetermined upper limit value to a predetermined destination. Characteristic e-mail communication method. 12. A step of transmitting an e-mail including image data, a step of receiving error information indicating that the transmitted e-mail has a large data size and has failed in transmission, and a step of receiving the error information. An electronic mail communication method comprising: an image data size reduction step of reducing the data size of the image data; and a step of transmitting an electronic mail including the image data of the reduced data size. 13. A step of calculating a data size of an electronic mail including image data, and when the data size of the electronic mail exceeds a predetermined upper limit value, the data size of the electronic mail exceeds the upper limit value. Until there is no more, execute the image data size reduction step to reduce the data size of the above image data and the mail transmission step to send an e-mail whose data size does not exceed the predetermined upper limit to a predetermined destination to the computer. A computer program for electronic mail communication, characterized by being used for performing. 14. A step of transmitting an e-mail including image data, a step of receiving error information indicating that the transmitted e-mail has a large data size and has failed to be transmitted, and a step of receiving the error information. E-mail communication, which is used for causing a computer to execute the image data size reduction step of reducing the data size of the image data and the step of transmitting an e-mail including the image data of the reduced data size. For computer programs. 15. A means for calculating a data size of an electronic mail including an attachment file, and when the data size of the electronic mail exceeds a predetermined upper limit value, the data size of the electronic mail exceeds the upper limit value. Until it does not exist, it has attachment file data size reduction means for reducing the data size of the attachment file, and mail transmission means for sending an electronic mail whose data size does not exceed a predetermined upper limit value to a predetermined destination. An electronic mail communication device characterized by. 16. A means for transmitting an e-mail including an attachment file, a means for receiving error information indicating that transmission of the e-mail has failed due to a large data size, and a method for receiving the error information. An electronic mail communication device comprising: an attached file data size reducing means for reducing the data size of the attached file; and a means for transmitting an electronic mail including the attached file with a reduced data size. 17. A means for calculating a data size of transmission target data, and, when the data size of the transmission target data exceeds a predetermined upper limit value, until the data size does not exceed the upper limit value. A data communication device comprising: a data size reducing means for reducing the data size; and a data transmitting means for transmitting data to be transmitted whose data size does not exceed a predetermined upper limit value to a predetermined destination. 18. A means for transmitting data to be transmitted, a means for receiving error information indicating that transmission has failed due to a large data size of the transmitted data, and when the error information is received, A data communication device comprising: a data size reduction means for reducing the data size; and a means for transmitting the transmission target data with the reduced data size. 19. A means for calculating a data size of an electronic mail including image data, and when the data size of the electronic mail exceeds a predetermined upper limit value, the data size of the electronic mail exceeds the upper limit value. Until it does not exist, it has an image data size reducing means for reducing the data size of the image data and a mail sending means for sending an electronic mail whose data size does not exceed a predetermined upper limit value to a predetermined destination. Characteristic mail user agent device. 20. A means for calculating a data size of an electronic mail including image data, and when the data size of the electronic mail exceeds a predetermined upper limit value, the data size of the electronic mail exceeds the upper limit value. Until it does not exist, it has an image data size reducing means for reducing the data size of the image data and a mail sending means for sending an electronic mail whose data size does not exceed a predetermined upper limit value to a predetermined destination. Characteristic mail transfer agent device.