JPS61290868A - Accumulated image information transmission system - Google Patents

Abstract

PURPOSE:To continue communication without suspending the communication and also without entering into an endless loop, by replacing the image information of a line concerned with the image information of one line before, or with optional image information, and transmitting it in a state that a memory error is corrected in case the memory error is detected when reading out the accumulated image information. CONSTITUTION:At the time of transmission, the image information from a memory device 5 is restored to its original picture data by an information reproducing part 7 and in an EOL detecting part 8, the head and the end of its line are detected. Restored image information of one line portion is stored in a line memory 10 and on the other hand, an error is detected depending on whether its bit length coincides with the number of picture elements corresponding to one line or not, by an error detecting part 9. When an error is detected, a memory error is corrected by replacing the image information of the error generated line with the image information of the previous line from the line memory 10 by an image information replacing part 11. Next, this image information whose error is corrected is sent out to a communication line 12 through a MODEM part 4 after its redundancy is eliminated by an information compressing part 3 through a switching part 2.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a stored image information transmission method that compresses and stores image information and then reads out and transmits the stored image information line by line at the time of transmission. The present invention relates to a stored image information transmission method in which, if an error occurs in the stored image information, the image information of that line is replaced with that of another line and then transmitted.

[Background of the invention]

As a facsimile machine capable of storing transmitted image information, there has been known a facsimile machine described in Japanese Patent Application Laid-Open No. 59-204577. FIG. 3 shows the block configuration of an example of such a facsimile machine. According to this, the reading processing unit 1 reads a document for broadcast communication, but the read image information is redundantly removed by the information compression unit 3 and then stored in the memory device 5°. It has become so. In this case, the convolution of the image information into the memory device 5 and the reading from it are performed under the control of the control circuit 6. When broadcast communication is started, the image information is repeatedly read out from the measuring device 5 for the number of destinations, and then transmitted to the communication line 12 via the mode JN (i demodulation) section 4. This is what has become. In this case, since the memory device 5 requires a large capacity memory of several megabytes or more, there is a risk of errors occurring when writing or reading image information. In the broadcast communication facsimile machine as shown in FIG. 3, if a memory error is detected when image information is read from the memory device 5, one of two methods is adopted. . That is, the first method is to stop the transmission, and the second method is to ignore the memory error and continue the transmission. The former method is very inconvenient because even a memory error that does not significantly affect the quality of the received image causes the transmission to be aborted. On the other hand, in the latter case, a memory error on the transmitting side may be determined to be a transmission error on the receiving side, which can be distinguished from a data error due to K such as noise on the transmission path, and communication may be terminated. Even if the communication is not stopped, if the error retransmission function is provided, there is a problem that the memory error line is repeatedly transmitted from the sending side to the receiving side, resulting in an infinite loop.

[Object of the Invention] The object of the present invention is to provide a method for transmitting stored image information in which communication can be continued without being interrupted and possibly going into an infinite loop even if a memory error is detected when reading stored image information. There is a method to provide.

[Summary of the invention]

For this purpose, the present invention provides that, when a memory error is detected when reading stored image information, the image information of the line is changed to the image information of the previous line, or any image information such as all white or all black. The data is replaced and the memory error is corrected before transmission. This eliminates problems caused by memory errors when facsimile stored image information on the sending side is successively produced.

[Embodiments of the invention]

The present invention will be explained below with reference to FIGS. 1 and 2.

FIG. 1 shows a block configuration of an example of a sending facsimile apparatus according to the present invention.

In this example, a document is read by a reading processing section 1, and its image information is sent through a switching section 2 to an information compression section 3 to have its redundancy removed, and is then temporarily stored in a memory device f5.

At the time of transmission, the image information from the memory device 5 is sent to the information reproducing section 7.
The line is restored to the original image data, but the EOL detection section 8 detects the beginning and end of the line.

While the restored image information for one line is stored in the line memo, the error detection unit 9 detects errors based on whether the bit length matches the number of pixels corresponding to one line. . If an error is detected, the error image information replacement section 11 replaces the image information of the line where the error occurred with the image information of the previous line from the line memory 10, thereby correcting the memory error and creating this error-corrected image. The information is passed through the switching unit 2, redundancy is removed by the information compression unit 5, and then sent to the communication line 12 via the modem unit 4.

The error detection mark generating section 13 is for adding an error detection mark to the previous line image information when replacing the image information of the line where the error occurred with that of the previous line. When the mark is added to either the Ni1 part or the rear part of the previous line image information, the mark is recorded as a straight line mark on the reception recording paper K in facsimile reception #, so that the line can be marked on the receiving side. It is easy to know that an error has occurred. Further, if an error occurs in the EOL, this is a problem, but this can be dealt with by treating two lines of image information as one line's worth of image information and detecting the error based on the bit length.

By the way, in the above example, the compressed image information is once restored to the original image data by the information reproducing section at the time of transmission.
Although the information is transmitted again after its redundancy is removed by the information compression unit, FIG. 2 shows the program configuration of an example of the sending facsimile apparatus according to the present invention in which it is not necessary to restore the original image data. This is what is shown. As shown in the figure, the EOL of the image data read out from the memory device 5 is detected in a compressed state, and the compressed image information for one line is stored in the line memory 10. On the other hand, the error line detection unit 9 detects an error when the stored image information is successively produced, but when an error is detected, the error image information replacement unit 11 replaces the image information of the error line with the previous line image information. This error-corrected image information is sent to the communication port +1 via the modem unit 4.
112. By the way, in this example, the error detection mark is added by replacing the image information of the line where the error was detected with any one line of coded data with the error detection mark, or by transmitting the previous line data as is and then adding the error detection mark. This can be dealt with by transmitting one additional line of encoded data.

Note that the line memory 10 in FIGS. 1 and 2 can also be used as a replacement pattern generating section that generates any pattern such as an all-white pattern or an all-black pattern.

〔Effect of the invention〕

As explained above, according to the present invention, as a result of correcting reading errors in information compressed image information and transmitting it as error-free image information, transmission is not stopped due to the occurrence of the error, and the transmitting side can This has the effect of preventing communications from being stopped due to errors being mistakenly judged as transmission errors on the receiving side, and from falling into an infinite loop due to erroneous retransmissions.

[Brief explanation of drawings]

1 and 2 are diagrams each showing a block configuration of a sending facsimile device according to the present invention, and FIG. 5 is a diagram showing a block configuration of an example of a conventional facsimile device capable of storing transmitted image information. It is. 1...Reading processing section 2...Switching section 3...Information compression section 4...Modem section 5...Memory device
7... Information reproducing section 8... EOL detection section 9...
・Error detection unit 10...Line memory 11...Error image information replacement unit 12...Communication line 13...Error detection mark generation unit 1AII2]

Claims (1)

[Claims] 1. In a stored image information transmission method in which compressed and stored image information is sequentially read line by line and then transmitted to the receiving side, an error was detected in the image information read out line by line. In this case, the stored image information transmission method is characterized in that the image information of the line is replaced with any one line of image information and then transmitted. 2. The stored image information transmission system according to claim 1, wherein any one line of image information includes an error detection mark.