JPS5859669A - Error control system of facsimile - Google Patents

Abstract

PURPOSE:To obtain a recording picture being faithful to an original, and also to shorten a time required for correcting an error, by resending an erroneous line picture signal of the original, and substituting a correct picture signal for this erroneous line picture signal which has been resent. CONSTITUTION:An erroneous line detecting circuit 16 counts the number of bits of a picture signal of its decoded line, checks an error of the line concerned, and if there is an error, a line number code stored in a line number detecting circuit 17 is stored as an erroneous line number code in a memory circuit 18. When a signal showing a picture signal end as to one sheet of original is received, a controlling circuit 19 transmits the erroneous line number code stored in the memory 18, to the transmitting side. In the transmitting side, a resending line number code arriving from a line number detecting circuit 6 is stored in order. A memory circuit 2 sends out a picture signal of a line corresponding to the resending line number stored in the detecting circuit 6, to the receiving side through an MODEM5.

Description

[Detailed description of the invention] Non-invention is Tsuaku vi! Concerning the meditation method of l.

In particular, we propose a control system in which, after the transmission of one sheet of original is completed, the image side number of the wrong line of the original is retransmitted.

In general, 7'AkPt5 image information is rounded off because of the correlation between two adjacent lines, and even if the erroneous line is replaced with the image signal of the previous line and recorded and reproduced, it is possible to obtain an ε recording that is approximately faithful to the original manuscript. Can be done. However, it is possible that xb occurs randomly and within an allowable range, and ge occurs in 9 cases.
For example, if #4) can occur on a burst hook over several lines, To or.

Incorrect] Number of lines is allowed. If it increases beyond this range, the recording quality will drop sharply. Therefore.

In this method, fatal ε recording occurs at 1 o'clock, and the original function of the facsimile machine is no longer coupled.

For this reason, recent facsimile machines.

Divide the facsimile image information into plotters for each unit,
A method has been proposed in which this error is performed on a block-by-block basis and the block is transmitted. but.

When trying to correct the error by retransmitting the block where the error occurred using the control method.

Naturally, a response is required for each block from the receiving AM to the sending AMTC, which means that the transmission time is increased by the time required for error control.

On the other hand, a method of performing incorrect control for one WL document as a unit,
In other words, rigid judgment of all received recorded images for one original,
In the case of poor quality, a method has also been proposed in which the blank original is resent from the beginning. This method does not require any time for error control compared to the case where error control is performed on a block-by-block basis when no error occurs or when the error is within an allowable range. However, it is necessary to retransmit every single line without errors, and therefore, considering that the number of lines without errors is generally much smaller than the lines with errors, retransmission is necessary. Therefore, method C can be implemented relatively inexpensively, but on the other hand, once an error occurs, the entire document must be retransmitted, especially in long-distance communication. has the disadvantage of high telephone charges.

The present invention was made against this background.

The WA control system of the present invention will be explained below with reference to the drawings.

The drawings schematically show the configuration of a nine-fax machine that implements the present invention, and FIG. 1 shows the transmitting side device.

Figure 2 is received af! It is a place.

Fig. 1 shows a reading circuit that optically reads the original document and converts it into an electrical 11 signal;
(2j is reading) The image signal obtained in 1st pass (1) is stored in at least %b of one original document and has a storage capacity, and 3J is sequentially output from main circuit (2). An encoding circuit (4j is an encoding circuit (3)
(5) is a line number code generation circuit that represents the line number of each image signal each time one line of WIR@ is introduced into J, and generates an appropriate code such as a binary code. Compensation 8t #modulated reception! modem circuit for returning II9;
16) is a line number detection circuit that detects the line number code sent back from the receiving side, and (7) is a series of 7 ac Vt! 7. A control circuit that controls the transmission operation, and (8) a connection terminal with the line. “First, in Figure 2, aD is the connection terminal to the line.

■ is a modem circuit that demodulates the received signal and modulates the transmitted signal;
U is a decoding circuit which decodes the encoded image signal to obtain the original lliill code, (14 has a capacity for storing at least one original document which is the image signal obtained from this decoding circuit); a first memory circuit, and II a recording circuit that records nine-picture signals successively output from this memory circuit.

1! aD is a line number detection circuit that detects the fin number code coming from the transmitting side; (18 is the 20th sled circuit that stores the line number code from the line number detection circuit w! 111 when the line detection circuit tte detects an erroneous line), and the fin is a series including the ε recording control. Faku V
19 This is a control circuit that controls the control a# of the recipient's movements.

Next, the operation of a certain facsimile machine will be explained with reference to FIG.

Now, suppose that the sending and receiving of control signals between the transmitting side and the receiving side at the start of communication has been completed, and the stage of transmitting the vR signal has begun. The takeover circuit (1) of the device (Fig. 11) starts reading the original under the control of the control circuit (7). The image signal read by the reading circuit (1) is stored in the memory circuit I.
The signal is stored in the memory circuit (2) and then sent to the encoding circuit (3) where it is encoded to reduce redundancy. Line number code creation circuit (4).

Each time the encoding circuit (33) derives the encoded output of each line, it increments the built-in counter by one.

The counting result (binary number) of the counter C is outputted to each line 1 as a line number code.

As shown in FIG. 6, this fin number code (kl) is serially inserted into the line synchronization code (OL) of each line derived from the encoding circuit (3) and the encoded picture signal (DRI). and then introduced into the modem circuit' (5).

The modem circuit (5) performs these six types of code ijK modulation and outputs it to the line via the line ItIk connection terminal (8). These operations are continued until the image signal transmission for one document is completed. As a result, the facsimile painter'?
At the transmission stage! A code string as shown in FIG. 1 will be output to the line. and.

When the above-mentioned principle for one manuscript is completed.

The control circuit (7) is a reading circuit (1) and an encoding circuit (3).
, the line number code t#-forming circuit (4) is stopped, and a control signal indicating the sending path Tt- of one document is generated and sent.

On the other hand, in the receiver side device Cf152), the receiver g4 even code is introduced into the modem circuit α station via the circuit Iil connection terminal aυ, demodulated, and then input to the decoding circuit al and line number detection circuit σn. Ru. The decoding circuit 1 first detects a line synchronization code (MOL) from the received code string shown in FIG. 5, and outputs the detection output to the line number detection circuit. The line number detection circuit α extracts and stores the line number code (LM) that arrives following the line synchronization code based on the detection output. Encoded image signals that arrive one after another (
Decoding the D signal and reproducing the original @ signal, 1st) 7g circuit 1
At this time, the control circuit (■) does not give any instructions to the recording circuit (9), and the recording circuit (9) does not operate. Upon completing the decoding of the signal, the 1IIb line detection circuit detects the 1111g! of that decoded line. ! The number of bits in the line is counted, and the line is ticked to see if there is an error.

If there is no error, the second number circuit does not operate, but if an error is detected, the line number detection circuit 17) stores the output from the line detection circuit (error). (Incorrect line number code) The line number is stored in the second memory circuit alk. These operations are performed by the sending device
The process continues until the TIII signal indicating the end of the IDmlIIi number T arrives for each incoming manuscript. Once this control signal is detected.

The control circuit unit immediately stops the operation of the decoding north circuit II (13) and at the same time checks the state of the second sled circuit.

As a result of this check, if the code for the second memory MQIK incorrect line is stored, the control circuit creates a control signal indicating a request for retransmission of the incorrect line and sends it to the transmitting device. Subsequently, the control circuit I instructs the second warping circuit section, whereby the sequentially stored incorrect line numbers p-F are introduced into the modem circuit I and transmitted to the transmitting device.

Next, at the transmitting side device, Ii! from the receiving Il device!
When a control signal requesting the retransmission of a duplicate line is detected by the control circuit (7), the control circuit (7) detects the retransmission twin number code of the incoming T line number (Ip) following the control signal. The line number detection circuit (6) instructs the line number detection circuit (6) to sequentially store the retransmission line number codes that arrive following the control l!! signal requesting retransmission of the erroneous line. When the retransmission line number code ends, the control circuit i1173 instructs the memo jl!!l1l (2) and line number detection circuit (6) K to retransmit the line corresponding to the retransmission line number. 5 circuit (2) is the wl! of the line corresponding to the retransmission line number stored in the line number detection circuit 16). The code 'kR is derived from the code 1 (3) and received via the modem 1 (5).
Send to device. These operations continue until transmission on all retransmission lines stored in the line a1:8 detection circuit (6) is completed.
The signal format output from the I device is as shown in Figure 6 above. ! This is exactly the same as when sending out a number. When the exit of all retransmission lines is completed, the control circuit (7) sends a control signal indicating completion of exit of the retransmission twin, and receives III IN!
with a response from the location.

On the other hand, in the 901GL device, when the exit of the erroneous line number code is completed, the retransmission line mig! Once the I signal is in reception status, we wait for an image signal from the transmitting side 5 km away. Send 11*
When the retransmission image signal from 1 arrives, the decoding circuit 1''e first converts the line synchronization code (OL) in exactly the same way as described above.
is detected, and the subsequently arriving line number code (X-shoulder) is detected by the line number detection circuit t7)fc.

Both signals are decoded by the decoding circuit a3.

According to the line number detected by the line number detection circuit (17), the first warping circuit (IIJK already stored error)
It is stored as being replaced with a line image signal. As a result, the igI signal with no errors is stored in the first warp circuit I. This operation is performed by sending g! It-instructing control to complete the transmission of the retransmission line from the I-side device (continues until No. 21 arrives).When the control g!Ilj arrives, the control circuit a9 controls the retransmission line ll1Rjj. Receiving 41! Indicates a confirmation T control signal is created and output to the transmitting side device. Then, when the transmission of the control signal C is completed T, the control circuit frfiL, "#gm first memory circuit I and storage Instruct circuit a9 to start recording.

As a result, the recording circuit aj is transferred to the memory ag! 1tt*Yoshi sequential image signal is derived and li! , replay the recording. At that time, the W! stored in the first Nomory path I! At! It is natural that i@ has no an, and a complete ε recording is reproduced in the subordinate f. Written like this @1w4aS
When all facsimile recording is completed, the receiving@1lil device completes a series of facsimile t9 receiving operations.

Also, the transmitting side device receives the retransmission line i from the receiving side device.
li@! The above-mentioned control number a indicating confirmation of receipt of the number is
Tru.

The above explanation is based on the second warp circuit Q in the receiving side device.
If the line number code is stored in step 8, but if the above code is not stored at all in the second note circuit, then after checking this note circuit, a control will be sent to indicate that the line number code was received normally. Create ag1 number and send it to the sending device. Then, upon detection of this control signal, the transmission lI
The M device finishes the transmitting operation, and at the reception level of 115kIiK, the electricity is turned off.As explained above, the error control system of the present invention is as follows.

After the transmission of one document is completed, the image signal of the S line of that document is retransmitted, and the retransmitted correct l1l of ξ is
Since the recording is performed by replacing the [Il signal of the ii error) line with the [Il signal], it is possible to always obtain an ε recording that is faithful to the original, and the time required to correct the error is relatively short. The advantage is that it takes only a short time.

[Brief explanation of drawings]

FIG. 1 shows a schematic configuration of a facsimile transmission 1111 device implementing the WA control method of the present invention, FIG. 2 shows a schematic configuration of a receiving device, and FIG.
It is a T diagram schematically showing No. i. (1) - Reading> circuit, (2) α4... Memo 51 circuit, (3) - Encoding circuit, (4) - Line number code F4'' circuit, (5) 1121. -Sodem episode W6
-161 (171 = line number detection m circuit, (73i
s1... control a [DJ path, (131-... decoding circuit, as-e recording m, am-i!!14 line detection circuit)

Claims (1)

[Claims] (1) On the sending side, the nine-stroke bias obtained from the original is stored in a memory with a capacity equivalent to at least one original, and each line is stored in the image of each line sequentially output from the nine memo means. At the same time, after the transmission of one sheet of original is completed, the TGA code of the line specified in response to a retransmission request from the receiving side is sent from the memory means. Again, it is retransmitted to the receiver with its twin showing board bias. ! ! ! In g1111, when the four signals of each line that have arrived are stored in the first memory means having phase separation teeth for one original document, llii errors in each line are detected line by line at the corners, False) Line code 4m48t'182 note Summer means lIc1 [Next storage, then? After the reception of one document is completed, the code stored in the upper epsilon (second) sledding means is sent one after another as a retransmission request to the sending side, and in response to this retransmission request, each m The @ number is rewritten into the first memory means, and the Ii & shi control method of the 9th Faku vIwo.