JPS5966265A - Decode error detecting system - Google Patents

Abstract

PURPOSE:To discriminate the quality of a received picture with a prescribed criterion, by providing a function detecting the presence of a decode error at each line and of a decoded line number to a decoder at the receiving side. CONSTITUTION:The decoder 2 outputs a line end signal to a line counter 4 every time a signal from a facsimile signal input terminal 1 is received and the decoding of one line is finished, and outputs a decode error to a counter 5 if a decode error is generated. The counter 4 counts the line number and outputs the result of calculation to a comparator 7. Further, the counter 5 counts the number of decode error generation and outputs the calculation result to the comparator 7. The comparator 7 resets the counters 4 and 5 when the output of the counter 4 becomes a reference line number L. Further, the comparator 7 outputs a receiving defective report from a receiving defective report terminal 10 when the decode line number becomes a permissible decode line number N.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a facsimile IJ transmission method using a redundancy suppression coding method such as a modified Huffman coding method. This invention relates to a decoding error detection method for determining whether image quality is good or bad.

(Configuration of conventional example and its problems) ``Conventionally, in the transmission system of facunmill signal using redundancy suppression coding method, the quality of the received image is judged by direct visual inspection of the received image output from the facunmill terminal. , by counting the number of lines with decoding errors detected during reception of image signals for one page.

However, the former case always has the disadvantage of requiring manual labor, and the latter case varies depending on the image size, standard or high quality reception mode, etc. There were disadvantages such as the need to change the number, complicating automatic reception processing.・゛(Objective of the Invention) The present invention has the purpose of solving these drawbacks. ・Even in the case of automatic reception without manual intervention, decoding errors in consecutive lines of a predetermined standard number of lines can be divided into two. The quality of the received image is automatically determined according to a certain standard by counting the number of images, and the drawings will be described in detail below.

(Description of Structure and Embodiments of the Invention) FIG. 1 is a block diagram showing the structure of an embodiment of the present invention.
] is F,, axis signal input terminal 1. ．． 2 is redundant.

4 is a line counter that counts the number of decoded lines, 5 is a decoding error 1 error counter, 6 and 7 are comparators, 8 company standard line number input terminals 1.9 are allowable 174 10 is an input terminal for the number of error lines N, 10 is a reception failure report output terminal, 11 is a reset signal input terminal for initializing each counter 4 and 5 at the start of reception, and 12 is an input terminal for the undecoded factor ξ signal. It is the output terminal □.

The decoder 2 is turned off, receives the signal from the 7mm IJ signal input terminal 1, and sends a line end signal to the line number counter 4 every time the decoding of one line is completed, and the decoding error is detected. If a decoding error occurs, a decoding error occurrence notification is output to the decoding error line counter 5. ,,
In: The number counter counts the number of lines and outputs the counting result to the comparator 6. A decoding error number counter 5 counts the number of lines in which a decoding error has occurred, and outputs the counting result to a comparator 7. The comparator 6 resets the line number counter 4 and the decode number counter 5 when the output of the line number counter 4 reaches the base number p.

7. ．． is de x -)' x 5-5 i, number,
8 permissible de, -de 5r-(yaN, 2): When the reception failure report output terminal 10 outputs a reception failure report.

In other words, the image signal of one page is divided into a plurality of blocks for each line based on the reference number of lines, and the number of decoded error lines is verified for each block, and even in kl blocks of one page, the number of decoded error lines is within the allowable decoding error. If the number of lines exceeds N, reception is not possible. Figure 2 shows the configuration of an example of application of this invention. 17 corresponds to terminal 15.
□Facsimile, storage and exchange, network 13 receives pictures from users and then sends them to various teams. Since the hiss is performed, it is necessary for the λ terminal support section 14 to provide a minimum guarantee for the image quality of the transmission/reception screen with the facsimile terminal 15. □Furthermore, since the IJ storage and exchange network 13 performs mutual communication with images of various sizes in a mixture of standard and high quality modes, the terminal support unit 14. By applying the present invention to, the above-mentioned necessary issues can be realized with a simple configuration.

(Effects of the Invention) As explained above, the present invention has the advantage that even in the case of automatic reception without human intervention, it is possible to judge the quality of the received image based on a fixed standard, regardless of the image size or mode. C1.
It is extremely effective in practical use.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a configuration diagram of an example of an application of the present invention. 1 ・・・・・・・・・7 AC 7mm signal input terminal 1.
2... Redundancy suppression decoder, 3...
...Buffer line memory, 4 ・i...
... Line number counter, 5...
・Decoding error number counter, 6, 7...
... Comparator, 8 ...... Input terminal for the number of reference lines, 9 ...... Input terminal for the number of allowable decoding error lines N, ..., l 10.・・・・・・
...Reception failure report output terminal, 11...
Reset signal input terminal, 12...Facsimile, IJ signal output terminal, 13...Facsimile IJ storage and exchange network, 14...Terminal Correspondence department, 15 rivers, mountains, facsimile terminals. Patent applicant Nippon Telegraph and Telephone Public Corporation NEC Corporation

Claims (1)

[Claims] 7 T' taxi signal transmission method using redundancy suppression method; In addition, the receiving side i-coder is equipped with a function to detect the number of decoded lines and the presence or absence of decoding errors for each line. In addition, reception is determined to be poor when the number of lines in which a decoding error is detected during continuous input of a predetermined standard number of lines exceeds a predetermined allowable number of decoding error lines N. A decoding error detection method characterized by: