JPH0314361A - Facsimile communication system - Google Patents

Abstract

PURPOSE:To prevent normally received image data from being doubly transmitted even by one line by informing the number of lines normally received from the receiving side by a facsimile control signal when an error is generated and resending image data of informed line and after from the transmitting side. CONSTITUTION:When an error interrupting communication occurs during facsimile communication, a transmission side facsimile equipment 1 executes resending processing. At that time, the equipment 1 executes transmission by the procedure similar to that of transmission, but at the time of deciding resending, transmission information and the number of lines normally received on the receiving side are read out from a memory part 4 and information indicating the specification of the function of this system and transmitting information are added to an NSS signal (non-standard function setting signal) and to send the NSS signal. After sending the NSS signal, preprocessing such as training check is executed similarly to normal transmission and then image data of the normally received line and after are successively read out from the memory part 4 and transmitted. Consequently, the normally received image data can be prevented from being doubly transmitted even by one line.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a facsimile communication system, and more particularly to a facsimile communication system that prevents double transmission of the same document when a communication error occurs.

(Prior Art) As facsimile machines have become more widespread, their functionality has become more sophisticated, and facsimile communication methods have been developed to reliably transmit documents. For example, there is one disclosed in Japanese Patent Laid-Open No. 58-194456. In this facsimile communication system, a facsimile device is equipped with an image memory, reads a document before transmitting it, and stores the image data in the image memory. At the time of transmission, image data is read out from the image memory in page order and transmitted page by page starting from the first line. At this time, the number of transmitted pages is managed by counting each time one page of image data is read from the image memory. If an error that interrupts communication occurs due to trouble on the line or the like during transmission, the entire image data of the first line of the page where the error occurred is retransmitted based on the page count number of the transmitted image data.

Therefore, without retransmitting the image data of the page that was normally transmitted, it is possible to retransmit the image data from the next page that was normally transmitted.

(Problem to be solved by the invention) However, in such conventional facsimile communication systems, image data is retransmitted starting from the first line of the page where the error occurred. Of these, normally received image data up to the line where the error occurred will be retransmitted twice. As a result, there has been a problem in that the communication fee for retransmission increases by the number of lines that are transmitted twice.

(Purpose of the Invention) Therefore, the present invention provides that when an error that interrupts communication occurs during facsimile communication, the receiving side notifies the number of normally received lines using a facsimile control signal, and the sending side receives the notification. By retransmitting the image data starting from the relevant line of the relevant page, the normally received image data can be
The purpose is to reduce communication charges by preventing double transmission even on the line.

(Structure of the Invention) In order to achieve the above-mentioned object, the present invention is such that a sending facsimile device equipped with an image memory temporarily stores image data for transmission in the image memory and then transmits the image data, and the receiving facsimile device transmits the received image data. This is a facsimile communication method between facsimile devices that stores data in the image memory, and if a page interruption error occurs during facsimile communication, the receiving facsimile device receives a facsimile control signal indicating the number of lines that have been successfully received for the page. The transmitting facsimile device adds information regarding the retransmitted image data to the facsimile control signal and transmits the facsimile control signal at the time of retransmission, and then restarts transmission from the image data of the line next to the normal reception line. It is characterized by Hereinafter, the present invention will be specifically explained based on examples.

FIG. 1 to FIG. 7 are diagrams showing an embodiment of the present invention.

FIG. 1 is a block diagram of a facsimile device 1 applied to the facsimile communication system of the present invention.
ly Memory) 3, memory section 4, scanner 5
, a plotter 6, a communication control section 7, a network control section 8, an image processing section 9, an operation section 10, and the like.

The ROM 3 stores a basic program for the facsimile device 1, a retransmission processing program of the present invention, etc.
The system control unit 2 controls each part of the facsimile machine 1 according to the program in the ROM 3, and
At the same time, the retransmission process of the present invention is executed.

The memory unit 4 is a large-capacity memory that stores transmitted image data and received image data, and also stores various information such as transmitted information and received information. The transmission information includes the destination, the file type of the transmitted image data, and the transmitted image data (
There are the number of pages and lines of image data (normally transmitted image data), and the received information includes the source, the file destination of the received image data, the number of pages and lines of received image data (image data that was normally received), etc. .

As the scanner 5, for example, C O D (Charge
Line/Coupled Device
A scanner is used to read the document line by line and output it as image data.

As the blotter 6, for example, a thermal recording device using a thermal element is used, and the printer 6 records directly on thermal recording paper or indirectly on ordinary recording paper via an ink sheet.

The communication control unit 7 exchanges facsimile control signals with the other party's facsimile machine and executes facsimile communication procedures. Further, as will be described later, the communication control unit 7 sends and receives facsimile control signals to which various information for performing retransmission processing of the present invention is added, analyzes the received facsimile control signals, and analyzes the various information. Take out.

A line L, such as a telephone line, is connected to the network control unit 8, and the network control unit 8 performs automatic call origination and call reception operations. The network control unit 8 also includes a modem, and modulates and demodulates transmitted and received signals.

The image processing section 9 includes an encoding/decoding section, an image reduction processing section, etc., and performs encoding processing, decoding processing, reduction processing, etc. of image data.

The operation unit 10 is provided with a display unit and various operation keys such as a numeric keypad, and the destination telephone number and various commands are input from the operation unit 10, and the display unit receives manual commands and transmits them to the operator from the facsimile machine l. Various information is displayed.

Next, the effect will be explained.

The following description will be made assuming that the facsimile machine 1 shown in FIG. 1 is installed on both the transmitting side and the receiving side.

When transmitting facsimile device 1 sends a document, when a document is set on scanner 5, transmission information such as the destination telephone number is input, and the start key is pressed, scanner 5 reads the document one page at a time starting from the first page. , is encoded by the image processing unit 9 and then temporarily stored in the memory unit 4. When the image data of all pages of the document have been stored in the memory unit 4, the sending (Tx) facsimile device 1 calls the receiving (Rx) facsimile device 1, as shown in FIG. , the receiving facsimile machine 1 receives the CE
A D signal (called terminal identification signal) and an NSF signal (non-standard function identification signal) are transmitted (step S1, St).As shown in FIG. Information indicating that it has is added.

On the other hand, as shown in FIG.
Analyze the signal and check whether information indicating the presence of the function of this method is added (step pt), and if the receiving side does not have the function of this method, perform normal transmission processing (step P,) . When the receiving facsimile device l has the function of this method, it checks whether the current communication is a retransmission (step P4), and if it is not a retransmission, it sends an NSS signal (non-standard function setting signal) (step P4). Ps). At this time, the sending facsimile device 1 adds information to the NSS signal to specify (execute) transmission using the function of this method, as well as sending information such as file name and sender's telephone number, as shown in FIG. do. The sending facsimile device 1 further transmits a TCP signal to perform a training check on the modem (step P6).
).

Check whether a CFR signal (receiving preparation confirmation signal) is transmitted from the receiving side (step pt). If training fails, the communication rate is lowered and training is performed again (step Pa). When the CFR signal is received, the image data is read out from the memory unit 4 while counting the number of lines from the first page and transmitted.Step P. ), when the transmission of one page of image data is completed (step P+
o) Send a post message (step Pz)
.

When the receiving facsimile machine receives the NSS signal (
Step 33) Analyze the NSS signal and check whether the function of this method is specified (Step S4)
．． If the function of this method is not specified, normal reception processing is performed (step 55), and if the function of this method is specified, the mode of the function of this method is set (step S
6). Next, check j-7 whether to retransmit (step S
7) If the image data is not retransmitted, the image data is received as is.

After the received image data is demodulated, it is temporarily stored in the memory section 4 and simultaneously passed to the image processing section 9 for decoding, and the number of lines is counted and stored in the memory section 4. The image processing unit 9 also checks for decoding errors, checks whether the number of decoding errors exceeds a predetermined threshold value or whether quality deterioration has occurred on the line, and counts the number of normally received lines (step Ss). When the reception of one page of image data is completed (step S,) and the post message is received (step SIo), an error that terminates the communication, that is, a decoding error exceeds a predetermined threshold value or It determines whether quality deterioration has occurred on the line (Stenop S++), and if it is received normally, it sends a signal indicating that the image data has been received normally, such as an MCF signal (message confirmation signal), and then Original page? Check to see if there is a transmission of
l■). When there is a document for the next page, the reception process for the next page is similarly performed (S+z), and when there is no next page, the communication is terminated.

In step Sll, when an error that interrupts communication occurs, the number of normally received lines is read from the memory section 4, and the number of normally received lines is added to a negative response signal and sent as shown in FIG. (Stethop S+4). Further, the image data that has been normally received is stored in the memory unit 4 together with the reception information, that is, the file name, the sender's name, the sender's telephone number, etc. (step S1).

On the other hand, after transmitting the post message, the sending facsimile device 1 waits for a response (step P1!), and if no response is received, performs normal glue recovery processing (step P13). When a response is received, it is checked whether the response has been received normally (step P.), and when it has been received normally, it is checked whether there is a next page in the manuscript (step Pus). If there is no next page, the communication is terminated, and if there is a next page, the next page is transmitted in the same way (step P4). When a negative response signal is received in step Pl4,
It is checked whether the number of normal reception lines has been added (step P+w), and if the number of normal reception lines has not been added, normal glue recovery processing, that is, retransmission processing from the page where the error has occurred is performed (step Pl3).
. When the number of normal reception lines is added in step P, the number of normal reception lines is stored in the memo U section 4 together with the transmission information, that is, the file size, destination, etc. At this time, even if the transmitting side facsimile machine 1 has finished transmitting one page of image data, it retains it in the memory unit 4 until it receives an acknowledgment from the receiving side that it has been successfully received. If an error that interrupts communication occurs during facsimile communication, the sending facsimile device l performs retransmission processing. At this time, the facsimile machine 1 performs transmission in the same manner as when transmitting, but if it is determined to be a retransmission in step P4, it reads the transmission information and the number of lines normally received on the receiving side from the memory unit 4, and reads out the transmission information and the number of lines normally received on the receiving side, As shown in , information specifying the function of this method and transmission information (file name of image data to be retransmitted, etc.) are added to the NSS signal and transmitted (step Pl9) - When the NSS signal is transmitted, normally After performing preprocessing such as a training check in the same way as when transmitting (Steps P6 and P.), the image data of the line next to the normally received line is sequentially read from the memory unit 4 and transmitted (Step P9). .

On the other hand, the receiving facsimile machine l, in step S,
If it is determined to be retransmitted, the image data of the normally received line is prepared among the image data of the error page of the communication file where the error occurred based on the NSS signal (steps S, t,), and the image data of the line next to the line where the error occurred is prepared. When the image data from the line is transmitted, these image data are concatenated and stored in the memory section 4 (step Sa). When one page's worth of image data is normally received, an acknowledgment is sent (step S, .), and the process is thereafter carried out in the same manner as in the case of normal communication.

Therefore, when retransmitting, normally received line data is
It is possible to prevent redundant transmission and reception, and it is possible to shorten the communication time for retransmission. As a result, communication charges can be reduced.

(Effects) According to the present invention, it is possible to prevent double transmission of even one line of normally received image data, and it is possible to reduce communication charges.

[Brief explanation of drawings]

FIGS. 1 to 7 are diagrams showing an embodiment of the facsimile communication system of the present invention. FIG. 1 is a block diagram of a facsimile device applied to the facsimile communication system, and FIG. 3 is a flowchart of the receiving process of the facsimile machine on the receiving side, FIG. 4 is a format diagram of the NSF signal, and FIG. 5 is a flowchart of the sending process of the facsimile machine on the sending side. FIG. 6 is a foreman diagram of the NSS signal, and FIG. 7 is a foreman diagram of the NSS signal. l...Facsimile device, 2...System control unit, 3...ROM, 4...Memory unit, 5...Scanner, 6 ... Plotter, 7 ... Communication control section, 8 ... Network control section, 9 ... Image processing section, 10 ... Operation section . message four

Claims (1)

[Claims] A facsimile communication method between facsimile devices in which a sending facsimile device equipped with an image memory temporarily stores image data for transmission in its image memory and then transmits it, and a receiving facsimile device stores the received image data in its image memory. , when a page interruption error occurs during facsimile communication, the receiving facsimile machine adds the number of normally received lines of the page to the facsimile control signal and sends it, and the sending facsimile machine sends the retransmitted image data when retransmitting. A facsimile communication method characterized in that after transmitting information by adding information regarding the facsimile control signal to a facsimile control signal, transmission is resumed from the image data of the line next to the normal reception line.