JPH05300354A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To limit a picture information error only to a top page by preventing the increase in the communication time due to occurrence of a picture information error. CONSTITUTION:The facsimile equipment is provided with an encoding/decoding section 5 counting a reception line number and an error line number and informing a control section of the result in the unit of one line, a RAM 4 storing respectively the counted normal line number and error line number, a ROM 3 to which a permissible error ratio of each transmission speed to decide an optimum transmission speed based on the ratio of the normal line number to the error line number is written, the control section 2 adding the optimum transmission speed to a message acknowledge signal as its information field and sending the result to an opposite sender side and the control section 2 analyzing the information field of the message acknowledge signal of the reception opposite party in the case of the operation by the transmitter side and executing the transmission of a line interface 1 at the optimum transmission speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile apparatus which changes a transmission rate when an image information error occurs.

[0002]

2. Description of the Related Art A conventional facsimile machine returns a retraining affirmative signal RTP or a retraining negative signal RTN as a response to a post message command when there is an error in image information. And the non-standard setting command N
Returning to the sequence of SS and the training signal TCF, retraining is performed to determine the transmission rate of the next image information.

[0003]

The above-mentioned conventional facsimile apparatus has a problem that the communication time becomes long because the retraining sequence is performed when an error occurs frequently during the transmission of image information. Further, if the result of the retraining happens to be normal, an error may occur even when receiving the image information on the next page, which is also a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a facsimile apparatus capable of preventing an increase in communication time due to occurrence of an image information error and limiting the image information error to only the first page.

[0005]

In order to achieve the above object, the facsimile apparatus of the present invention counts the number of error lines of image information and determines the optimum transmission rate from the ratio of the number of error lines to the total number of received lines. And a means for adding the optimum transmission rate to the message confirmation signal as an information field when operating as a receiving terminal, and when operating as a transmitting terminal, the information field of the message confirmation signal from the receiving party. Parse
It is configured to determine a designated optimum transmission rate and perform transmission at this optimum transmission rate. Preferably, the calculating means counts the number of received lines and the number of error lines and notifies the number of received lines on a line-by-line basis. A conversion unit, a RAM for storing each of the counted up normal line and error line, a ROM for writing an allowable error ratio of each transmission speed, a ratio of the normal line number and the error line number, And a control unit that determines the optimum transmission rate from the allowable error ratio of the ROM.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram of the facsimile apparatus of this embodiment. This facsimile apparatus includes a circuit interface 1, a control unit 2, a read-only memory (ROM) 3, an occasional write / read memory (RAM) 4, an encoding / decoding unit 5, a reading unit 6, and a recording unit 7.

The control unit 2 is a microprocessor (MPU)
And executes a program written in the ROM 3 to execute transmission / reception of the communication procedure shown in FIG. 2 and predetermined control for the line interface 1, the encoding / decoding unit 5, the reading unit 6, and the recording unit 7. .. When this facsimile apparatus operates as a transmission terminal, the image information read by the reading unit 6 is encoded by the encoding / decoding unit 5 according to a predetermined encoding method. Then, it is modulated by the modem of the line interface 1 and transmitted. A procedure signal such as an initial identification signal is generated in the control unit 2 and sent from the line interface 1 to the line.

On the other hand, when operating as a receiving terminal, the image information transmitted from the transmitting terminal of the other party is demodulated in the modem of the line interface 1. Then, after being decoded by a decoding method corresponding to a predetermined code in the encoding / decoding unit 5, it is recorded and reproduced in the recording unit 7.

The received procedure signal is notified to the control unit 2 via the line interface 1 and analyzed.
Furthermore, the number of received lines and the number of error lines are
The encoding / decoding unit 5 notifies the control unit 2 on a line-by-line basis. Then, in the control unit 2,
Count up by the counters prepared for each of the normal line and the error line. Furthermore, RAM4 is
The result of each line notified to the control unit 2 is stored.

The above operation is performed until the page end signal RTC is detected, and after this detection, the ratio between the number of normal lines and the number of error lines is calculated, and the optimum transmission rate is calculated from the allowable error rate of each transmission rate written in the ROM 3. decide. The determined optimum transmission rate is the information field FIF of the message confirmation signal MCF which is the response symbol of the post message.
Is notified to the partner's sending terminal. In the transmitting terminal, the MCF FIF notified to the control unit 2 is analyzed by the MPU, and the transmission rate of image information is set in the modem of the line interface 1. After that, the image information of the next page read by the reading unit 6 is transmitted to the receiving terminal at the optimum transmission speed.

Next, the communication procedure of this facsimile will be described with reference to the control sequence diagram shown in FIG.
In FIG. 2, the transmitting terminal 10 and the receiving terminal 20 mutually confirm that they are facsimile terminals by a predetermined procedure of phase A after the line is closed, and then proceed to the procedure of phase B. That is, the receiving terminal 20 sends an initial identification symbol consisting of a non-standard maintenance signal NSF indicating a non-standard capability unique to the user, a receiving station identification signal CSI, and a digital identification signal DIS featuring the standard CCITT capability to the transmitting terminal 10, (Step 11). At this time, the fact that the receiving side has the ability to specify the transmission rate,
The sending terminal 10 is notified by NSF.

The transmitting terminal 10 determines the transmitting station identification signal TSI, the non-standard setting instruction NSS, and the training signal TC based on the analysis result of the content of the initial identification signal and the content specified by the operator.
A signal consisting of F is transmitted (steps 12 and 13). At this time, the receiving terminal 20 indicates that it has the ability to transmit image information at the transmission speed designated by the receiving side by the NSS.
To notify.

After that, the process shifts to the transmission of image information through a predetermined procedure. That is, the transmission signal is transmitted from the transmission terminal 10 (step 13), the reception terminal 20 returns the reception preparation confirmation signal CFR (step 14), and the image information PIX is transmitted from the transmission terminal 10 (step 15). ..

The receiving terminal 20 counts the number of error lines and the number of receiving lines while decoding the image information, and determines the optimum transmission rate from the ratio of the number of error lines to the total number of receiving lines after receiving the image information. To do. Then, the multi-page signal MPS is transmitted from the transmitting terminal 10 (step 16). The receiving terminal 20 adds the determined transmission rate as an information field FIF to the message confirmation signal MCF, which is a response to the post message, and notifies the transmitting terminal 10 of it (step 17). After that, the transmitting terminal 10 analyzes the contents of the FIF of the MCF, and starts transmitting the image information of the next page at the designated transmission rate (step 18). As a result, the next page communication can be performed without an image information error due to the optimum transmission speed.

[0015]

As described above, according to the present invention, even when an error occurs frequently such as transmission of a plurality of pages on a noisy line, the increase of the communication time due to the occurrence of the image information error is prevented and the image information error is prevented. Can only be on the first page.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a facsimile apparatus according to this embodiment.

FIG. 2 is a control sequence diagram of communication in the above.

[Explanation of symbols]

 1 line interface 2 control unit 3 ROM 4 RAM 5 encoding / decoding unit 6 reading unit 7 recording unit

Claims (2)

[Claims] 1. The number of error lines of image information is counted,
When operating as a receiving terminal, the calculating means for determining the optimal transmission rate from the ratio of the number of error lines to the total number of receiving lines and the adding means for adding the optimal transmission rate to the message confirmation signal as an information field are provided. When operating as a terminal, a facsimile machine characterized by analyzing an information field of a message confirmation signal from a receiving party to determine a designated optimum transmission rate and performing transmission at this optimum transmission rate. 2. The calculating means comprises: a code / decoding unit for counting the number of received lines and the number of error lines and notifying them in units of one line; and a RAM for storing each of the counted normal lines and error lines. , A ROM in which the allowable error ratio of each transmission speed is written, and a control unit which calculates the ratio of the above normal line number and the above error line number and determines the optimum transmission speed from the allowable error ratio of the above ROM. The facsimile apparatus according to claim 1, wherein: