JPH0352378A - Facsimile communication system - Google Patents

Abstract

PURPOSE:To attain re-reception from a sender side facsimile equipment without the operation of the operator by sending a retransmission request signal to the sender side facsimile equipment when a picture quality check circuit discriminates the picture quality to be deficient. CONSTITUTION:A receiver side facsimile equipment is provided with a picture quality check circuit 7 discriminating the deficiency of picture quality of a decoded picture data and when the picture quality check circuit 7 discriminates the picture quality to be deficient, a retransmission request signal is sent to an opposite facsimile equipment. On the other hand, the sender facsimile equipment stores the picture data sent to the receiver facsimile equipment into a code memory 6 and sends the picture data stored in the code memory 6 to the receiver facsimile equipment when the retransmission request signal is received, when the received picture data is decoded later and discriminated to be deficient picture quality, the receiver facsimile equipment receives again the picture data without intervention of the operator from the sender facsimile equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a facsimile communication system in which received image data is temporarily stored in a code memory.

(Example) Conventional technology In general, 63 facsimile machines receive (lI)
If one facsimile machine does not correctly decode the received message, the received image quality will deteriorate, which is undesirable. Therefore, every time a - line worth of signals is decoded. A detection circuit is provided to detect whether or not the line is normally decoded, and the number of lines that are not normally decoded is counted. When this ltt value reaches a preset value, it is notified that the received image quality is poor. R T N
A (Retrain Negative) signal is sent to the sending facsimile machine, and the sending facsimile machine that receives the RTN signal is forced to warn of the retransmission of the document by, for example, turning on a poor communication lamp.

In addition, in G4 facsimile machines, if the image quality is poor, the receiving facsimile machine sends an RDPBN signal to notify the sending OI1 facsimile that the page could not be received correctly. It is configured to notify the device. This type of technology is known, for example, in Japanese Patent Application Laid-Open No. 52-931.
For details, see Publication No. 2 and Japanese Unexamined Patent Publication No. 53-83513.

(C) Problems to be Solved by the Invention However, in facsimile machines that store received image data in a code memory and decode it later, the line is already disconnected at the time the image data is decoded. If the image quality is poor, operator action is required to notify the sending facsimile machine of this fact.

(2) Means for Solving the Problems The present invention stores image data received from a sending facsimile machine in a code memory, and later decodes the image data in a data compression/expansion circuit. an image quality check circuit for determining whether the image quality of the received image data is good or bad, and when the image quality check circuit determines that the image quality is poor, it sends a retransmission request signal to the facsimile machine of the other party; The transmitting side 7 axillary device stores the image data transmitted to the receiving facsimile device in a code memory, and upon receiving the retransmission request signal, transfers the image data stored in the code memory to the receiving facsimile device. This is a facsimile communication method characterized by sending data to

(E) Effect According to the present invention, if the received image data is determined to have poor image quality when it is later decoded, the receiving facsimile device reproduces the image data from the transmitting facsimile device without operator intervention. Can receive.

(F) Embodiment FIG. 1 shows a circuit F of a receiving facsimile machine according to the present invention.
FIG. 2 is a block diagram showing II Ebisu.

In FIG. 1, (1) is a main IUP circuit that controls the entire facsimile machine, and specifically utilizes a microprocessor. This main control circuit (1) includes a reading circuit (2), a data compression/expansion circuit (3), a communication control circuit (4), a recording circuit (5), a code memory (6), a meat quality check circuit (7), etc., which will be described later. Controls the control of M.

The reading circuit (2) is subjected to NIFR using a scanner using, for example, a one-dimensional line sensor, and its maximum readable size is defined by the effective width of the line sensor. Due to this R circuit (2)! & taken manuscript drawing mt
The R report is transferred to the data compression/expansion circuit (3).

The data compression/expansion circuit (3) compresses and encodes the image data obtained as dot data in units of, for example, one line for transmission, or decodes the received image data (compression code).

The code memory (6) is constituted by a hard disk or the like, and stores received image data or image data for transmission that has been read by the reading circuit (2) and compressed and encoded by the data compression/expansion circuit (3). .

The control circuit (4) controls the input and output of signals to and from the communication line (9).

The recording circuit (5) has a "C'groove" such as a laser printer or a thermal printer, and the printing element scans in the main scanning direction and moves the recording line in a direction perpendicular to this, that is, in the sub-scanning direction.

The image quality check circuit (7) checks the image quality of the image data decoded by the data compression/expansion circuit (3).

It should be noted that although the above-mentioned facsimile machine has been described as a receiving facsimile machine, the same applies to the transmitting facsimile machine, so the explanation thereof will be omitted. Further, the self-quality check circuit (7) is not necessarily required in the sending facsimile machine.

The operation of the receiving facsimile device when image data received from the sending facsimile device is decoded and the image quality of the decoded image data is poor will be described with reference to the flowchart of FIG.

The receiving facsimile machine starts receiving image data (compressed code) from the transmitting facsimile machine, and stores the second image data in the code memory (6) via the communication control circuit (4).

Before this reception, the receiving facsimile device needs to check whether the sending facsimile device can retransmit, and if it can retransmit, it needs to obtain identification information and a telephone number that identify the image data to be sent from the sending facsimile device. There is. Specifically, in G3FAX, \SF, NS
Since non-standard functions are negotiated in S, the receiving facsimile machine specifies that it has the ability to request retransmission in the case of poor image quality, while the sending facsimile machine, when receiving a retransmission request, It indicates that it has a retransmission function and also sends identification information.

Also, with G4FAX, CDCL. Negotiate with RDCLP and CDS.

Also, the telephone number of the sending facsimile machine is G3 FA.
In case of Obtainable.

At the end of reception, it is assumed that the image data has been received correctly, and a normally received signal (for example, G 3 F A
In X, MCF. In G4 FAX, RDEP, etc.) is sent to the sending facsimile machine. As a result, the communication itself ends normally. Thereafter, the image data stored in the code memory (6) is decoded line by line by the data compression/expansion circuit (3), and the decoded image data for l lines is recorded by the recording circuit 1j). Note that recording is not performed when the recording circuit (5) cannot be used due to copying or the like.

Next, the image quality check circuit (7) checks the image quality of one line of image data. In this embodiment, when the number of erroneous lines exceeds a certain value, i! The image quality is checked by setting i1 as poor quality.

If the image quality check circuit (7) determines that the line is normal, or if the total number of erroneous lines does not reach a certain value even if it is determined to be an erroneous line, there is no problem and the process moves on to the next line. However, if the number of erroneous lines exceeds a certain value, it is determined that the quality is defective.

In this case, since the telephone number and identification information of the sending facsimile machine have been obtained as described above, a call is made to that telephone number using the communication control circuit (4). When the line is connected, a retransmission containing identification information is required. The R signal is sent to the sending facsimile machine.

Specifically, in G3 FAX, the receiving facsimile machine sends out a retransmission request signal using the NSC. Also, G4FA
For X, the receiving facsimile device is CDCL, RDCLP.
``C identification information is sent, and then cscc is sent.

Next, the operation of the transmitting facsimile machine is explained at 7 in Figure 3.
This will be explained according to the diagram.

At the time of transmission, the stroke data read by the reading circuit (2) and compressed and encoded by the data compression/expansion circuit (3) is stored in the code memory (6) and transmission to the receiving facsimile device is started. Before transmitting this image data, the sending facsimile machine notifies the receiving facsimile machine that it can be retransmitted. After that, when a normal reception signal is received from the receiving facsimile machine, the transmission ends and the timer is started. Is the image data relevant? It is held until the timer 1 determines the time error. During this time, when an incoming call occurs and a retransmission request signal is received, image data based on the rare identification information in the signal is read from the code memory, and this image data is sent to the receiving facsimile machine.

In the flowchart of FIG. 2, if the retransmitted self-statement data is defective (1), the same process as described above is repeated again, but the number of times may be limited to a predetermined number of times.

Furthermore, although the sending facsimile device stores the image data in the code memory (6) at the time of transmission, it is also possible to store the image data in the code memory (6) before transmission. As is clear, in the receiving facsimile machine that stores image data in a code memory and later decodes the image data in a data compression/expansion circuit, if the image quality of the decoded image data is poor, no operator operation is required. can be re-received from the sending facsimile machine.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a facsimile device according to the present invention;
FIGS. 2 and 3 are flowcharts for explaining the present invention. (1)...Main control circuit, (2)...Reading circuit, (3
〉...data compression/expansion circuit, (4)...communication control circuit, (5)...recording circuit, (6)...code memory,
(7)...Self quality check circuit.

Claims (1)

[Claims] (1) A receiving facsimile device stores image data received from a sending facsimile device in a code memory, and later decodes the image data in a data compression/expansion circuit.
An image quality check circuit is provided to determine whether the image quality of the decoded image data is good or bad, and when the image quality check circuit determines that the image quality is poor, it sends a retransmission request signal to the sending facsimile device, and , the sending facsimile device stores the image data transmitted to the receiving facsimile device in a code memory, and upon receiving the retransmission request signal, transmits the image data stored in the code memory to the receiving facsimile device. A facsimile communication method characterized by sending data to