JPH04109761A - Pictorial communication equipment - Google Patents

Abstract

PURPOSE:To improve the efficiency of a communication job further by adding a mark indicating an error location to an unarrival notice picture at the transmission of an ECM(error collection mode), informing the degree of missing information and providing a criterion of the necessity of the retransmission. CONSTITUTION:When a dot counter BC reaches 0, a bit data is extracted in the unit of 8 bits from a picture retransmission buffer memory 20 and whether or not a frame is a transmission error frame is discriminated, and when the frame is an error frame, an error mark (black mark of a prescribed length) is added to a prescribed position of a print line buffer and the resulting data is printed out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image communication device having a transmission function using an error correction method (ECM).

More specifically, the present invention relates to an image communication device that can be applied to, for example, a store-and-forward type facsimile device with an error correction function that stores a portion of a transmission image in a memory before transmitting it.

[Prior Art] Conventionally, in this type of facsimile machine, when an image stored in the memory is not successfully delivered to the receiver due to some reason such as the receiving station being busy and being unable to connect or a communication error, etc. A so-called non-delivery notification output function is widely known, which is a function of adding and outputting a part or all of the original transmission image to communication result information and notifying the transmitter operator.

[Problems to be Solved by the Invention] However, in the above conventional example, a part or all of the first page of the image that was attempted to be sent is added to the non-delivery notification when an error occurs and output. , it had the following drawbacks.

In other words, even when sending in ECM (Error Collection Mode), there is no way to identify which page and which part of the image was defective on the non-delivery notification image (for example, if the actual error occurred after the image) Even if there was only a blank area at the edge and no necessary information was missing, the operator had no choice but to resend the page where the error occurred.

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned points, an object of the present invention is to provide an image communication apparatus configured to allow an operator to specify a location where a transmission error has occurred.

[Means for Solving the Problems] The present invention provides an image communication device having a transmission function using an error correction method, in which an error does not disappear even if retransmission is repeated during transmission using the error correction method, and an error frame is generated. a non-delivery notification means for transmitting an image for non-delivery notification when resending of the non-delivery notification is given up; and an instruction means for adding a predetermined mark to a location corresponding to an error frame on the non-delivery notification image. It is equipped with

[Function] According to the above configuration of the present invention, by adding a predetermined mark to a location corresponding to an error frame on a non-delivery image at the time of ECM transmission, the error occurrence location is clearly indicated, and the degree of missing transmitted information, Alternatively, it becomes possible to inform the operator of criteria for determining the necessity of retransmission.

C Embodiment j Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a basic block diagram of a facsimile machine according to an embodiment of the present invention.

In FIG. 1, l is the main control unit that controls the operation of the entire device, including a microprocessor and a program memory R.
Consists of OM, work area RAM, etc.

Reference numeral 2 denotes a reading section that includes a COD image sensor, a document conveyance mechanism, and the like.

Reference numeral 3 denotes a recording section composed of a thermal printer, a laser printer, or the like.

4 is a communication control unit composed of a modem, an NCU (network control unit), and the like.

5 is this telephone.

6 is a communication line (telephone line).

Reference numeral 7 denotes an operation input section consisting of a keyboard and the like.

Reference numeral 8 denotes a display section composed of an LCD (liquid crystal display) or the like.

20 is a buffer memory for image retransmission, and 30 is a buffer memory for encoding during transmission.

40 is a transmission image storage memory included in a known store-and-forward type facsimile machine, and the image read by the reading section 2 is MH.

The information is encoded and stored using a known encoding method such as MR or MMR or an original encoding method.

When transmitting in the ECM mode, the main control unit 1 reads the contents of the transmission image storage memory 40, decodes it once, re-encodes it in accordance with the encoding method of the destination receiver, and transfers it to the encoding buffer memory 30 at the time of transmission. Transfer to. Furthermore, CCITT
According to the recommendation, 256 octets are extracted from the buffer, added with an address, control, FCD, and frame number (total of 260 octets) to form an IDLc frame, and sent over the line via the modem.

At this time, data for retransmission is transferred to an area corresponding to the frame number of the image retransmission buffer memory 20 as shown in FIG.

When an error occurs in a transmission frame during image transmission, when a request for retransmission of the error frame is received from the receiver using a PPR (partial page request) signal, the frame for which retransmission is requested is extracted from the image retransmission buffer memory 20, and the frame is sent to the HDLC.
Frame it and send it out over the line via the modem.

If the error frame does not disappear even after repeated retransmissions due to poor line conditions, etc., abandon the transmission after a predetermined number of times and terminate the communication, following the flowcharts shown in Figure 3 (A) and Figure 3 (B). , outputs a non-delivery notification as illustrated in FIG.

However, CCIT standard manuscript (#1) must be set in standard mode + 3.
75β/mm), the number of frames is approximately 72 frames. Therefore, in this embodiment, for convenience, it is assumed that image information is evenly distributed on one A4 size page.
4.125mm per frame (A4 length 297mm/
The fourth example shows an example in which an error frame mark is added for frame 72).
Shown in the figure.

In the flowchart shown in FIG. 3(A), first in step S1, various registers are initialized. In other words, the decode pointer for printout should be set at the start address of the image retransmission buffer memory 20.
P=0), clear the bit counter that indicates how many bits of the byte data have been processed (BC=O), and set the initial value to the 256 byte counter for framing (FBC=256), decode processing Set the frame index register to indicate the frame inside to O (FIX: 0). Also clear the control flag for adding error lines (EF=0).

From the next step S2 onwards, decoding and printing processing is performed for each line.

First, in step S2, the encoding mode MR/M during communication is
Data is processed bit by bit and decoded sequentially according to H, but when bit counter BC・0 becomes 0,
Bit data is extracted in units of 8 bits from the image retransmission buffer memory 20. That is, in step S21 shown in FIG. 3(B), it is determined whether the frame pointed to by the frame index register is a transmission error frame, and if it is an error frame, an error flag is set in step S22 (EF=1). , then step 32
3 to S25, one byte of data is taken out, the decode pointer is advanced by one (DP=DP+1), and the bit counter is set (BC=8). Furthermore, the byte counter for framing is decremented by one (FBC=FBC-
When 11°FBC=O (step 527), the FBC is reset in steps 328 and 329 (FBC=256), and the frame index register is advanced by one (FIX=FIX+1).

In step S2, data is extracted and decoded using this method, and the print data is transferred to a known print line buffer.

In the next step S3, it is determined whether or not a page end code (RTC) is detected during the decoding process, and if the page end is found, the output process of the undelivered image is ended. If it is not the page end, the process advances to step S4, where it is determined whether or not a line end (EOLI) has been detected, and if it is not the line end, the process returns to step S2 to continue the decoding process. In S5, the value of the error line flag (EF) is determined.

If EF=O, since the line is not an error frame, the print line buffer set at the time of decoding is printed as is (step 511).

If EF=1, the line is an error frame, so the processes from steps 36 to S8 are performed, that is, an error mark (black of a predetermined length) is added to a predetermined position in the print line buffer before printing is performed. At the same time, the error line flag is cleared for processing the next line (EF=[l
).

In the above-described embodiment, the degree of information loss is clearly indicated by adding an error mark to the original transmitted image. However, if the image error processing method of the receiver is known in advance, the error The undelivered image may be output using the same process as the error image printing process on the receiver side, such as a line skipping method or an interpolation method such as copying the previous line.

[Effects of the Invention] As explained above, according to the present invention, a mark indicating an error location is added to a non-delivery notification image when transmitting an ECM (error collection mode), and the degree of information missing is notified to the operator. , by providing criteria for determining the need for retransmission.
It will be possible to further improve the efficiency of communication operations.

[Brief explanation of the drawing]

FIG. 1 is a basic block diagram of a facsimile apparatus according to an embodiment of the present invention, FIG. 2 is a configuration diagram of a retransmission image buffer according to an embodiment of the present invention, and FIGS. 3(A) and 3(B) 4 is a schematic flowchart of a non-delivery image output process in an embodiment of the present invention. FIG. 4 is a diagram showing an example of a non-delivery image in an embodiment of the present invention. 1... Main control unit, 2... Reading unit, 3... Recording unit, 4... Communication control unit, 5... Telephone, Figure 1 6... Line, 7... Operation Input unit, 8... Display unit, 20... Buffer memory for image retransmission, 30... Buffer memory for encoding during transmission, 40... Memory for storing transmitted images. Frame number Figure 2 Figure (A) Figure (B)

Claims (1)

[Scope of Claims] 1) In an image communication device having a transmission function using an error correction method, an error does not disappear even after repeated retransmissions during transmission using the error correction method, and retransmission of an error frame is abandoned. the non-delivery notification means for transmitting an image for non-delivery notification; and an instruction means for adding a predetermined mark to a location corresponding to the error frame on the non-delivery notification image. Image communication device.