JPS58196767A - Error detection system - Google Patents

Abstract

PURPOSE:To permit a customer not to pay the charge for the use of a circuit in case of a defective recorded picture by discriminating a defective recordded picture if the frequency of error occurrence is high even when the number of error lines is less than a specified value. CONSTITUTION:A decoding circuit 2 outputs an addition signal 12 to a counting circuit 4 for the number of successive error lines to increase a counted value 1. Once decoding for one line is carried out normally, the counted value is reset by the decoding circuit 2. The counted value of the counting circuit 4 is inputted to a comparison and discrimination circuit 6; when the counted value is greater than the specified value, a defective recorded picture detection signal is supplied to a display circuit 11 through an OR circuit 10. A reset signal from a decoding circuit 2 is supplied to a counting circuit 7 for the frequency of occurrence of line error and its counted value is supplied to a comparison and discrimination circuit 9. When the frequency of error occurrence for a specified number of line is greater than the specific value, the defective recorded picture detection signal is supplied to the display circuit 11 through the OR circuit 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting errors caused by defective recording in a factor-t calculation device.

In the conventional error detection method, image data is 12-in decoded, and if the result is an error line, the number of consecutive error lines of this error line is counted by a continuous error line number counting circuit, and then, This count value is compared with the number of consecutive error lines, the allowable upper limit value, and the allowable upper limit value N obtained by the setting circuit in a comparison/judgment circuit, and if the count value exceeds N, an error signal is displayed. It was outputting to the circuit and indicating a defective recording surface. This error detection method detects failures caused by continuous errors in decoding caused by code bit errors, which occur intensively due to line burst noise.
It is effective in detecting However, if a large number of errors of less than N lines occur due to bit errors in the code that occur randomly due to random noise in the line, an ineffective and low-quality recording surface is obtained, and the errors occur. There were five drawbacks in that customers were often unable to decipher the transmitted image information because it was scattered on the recording surface. Furthermore, in the conventional error detection system, when a defective recording is detected, the display circuit transmits a signal requesting the transmitting side to stop transmitting image data, and the transmitting side stops transmitting the next image data.

However, when an error occurs in less than N lines due to random noise, the signal requesting the transmission stop is not output, and the next document is transmitted over the same line. As a result, since it is transmitted over the same line, there is a high probability that the next recording will be of low quality due to the same random noise, and the customer will have to pay the line usage fee even though they receive a defective recording. There were drawbacks.

An object of the present invention is to determine a defective recording surface if the number of errors is large even if the number of errors is less than a certain line, and to accurately display the defective recording surface to the customer and disconnect the line.

The features of the present invention are when continuous errors occur on the recording surface over a certain value, and when errors occur more than the number of errors set according to the length of the recording surface even if the continuous errors are less than a certain value. In either case, the purpose is to detect defects on the recording surface.

Hereinafter, specific embodiments according to the present invention will be described with reference to the drawings.

In advance, the decoding circuit 2 outputs reset signals 15 and 14, and outputs the continuous error line number counting circuit 4 and the number of occurrences i of lie/wA errors! After counting the number of rts and the number of recorded lines in circuit 7, the count value of circuit 8 is cleared, which sets the allowable upper limit for the number of line errors that occur in proportion to the number of recorded lines. Next, times? I
When image data is transmitted from M1, the decoding circuit 2 starts decoding and converts it into a black and white binary signal.

Decoding is executed until the end of one line of image data, and finally it is determined whether one line has been successfully decoded.

As a result, if the decoded data is successfully completed, the decoded data is transferred to the recording circuit 3 and recording is started, and then decoding is started again. However, when the error ends, the decoding circuit 2
After data is transferred to the recording circuit 6, the following processing for detecting a defective recording surface is executed. 1
That is, the addition signal 12 is outputted from the decoding circuit 2 to the continuous error line number counting circuit 4, and the counted value is incremented by 1. However, when the decoding is sequentially executed and one line ends normally, the count value is cleared by the decoding circuit 2 outputting the reset signal 15. This count value is output to the comparison/judgment circuit 6. Further, the allowable upper limit value N of the number of errors is determined by the comparison judgment circuit 6 from the allowable upper limit value setting circuit 5 for the number of consecutive error lines.
is output to. The value of N is a value that is preset according to the line quality. Next, the comparison/judgment circuit 6 compares the Δ value to the allowable upper limit of the number of consecutive error lines, and as a result,
When the count value is less than N, a defective recording image signal is not output, but when it is greater than or equal to N, a defective recording detection signal is output.

This signal is outputted to the display circuit 11 through the OR circuit 10, and automatically displays to the Km customer that an invalid recorded image has been detected. Furthermore, this display circuit 11 transmits a signal 16 requesting the sending/receiving side to stop transmitting image data.

On the other hand, in the process described below, defective recording detection based on the number of occurrences of line errors is executed simultaneously with the above process. This will be explained in detail below. First, the reset signal 15 from the decoding circuit 2 is output to the line error occurrence count circuit 7, and the count value is incremented by 1. This count value is output to the comparison/judgment circuit 9. After counting the number of recording lines, a circuit 8 for setting an allowable upper limit value for the same number of line errors that is proportional to the number of recording lines receives an addition signal 15 from the decoding circuit 2.
is input and counts the number of recorded lines, and at the same time, for each fixed number of lines, a fixed number is sequentially added to the upper limit value M of the number of errors to obtain a value of M proportional to the number of lines, and the value is sent to the comparison judgment circuit 9. Output. However, the allowable upper limit value M of the number of line error occurrences is a value obtained by calculating the product of the number of self-recorded inputs and the probability of error occurrence per line preset based on the line quality.

Next, the comparison/judgment circuit 9 compares the counted value with the allowable upper limit value M. When this cumulative total stem value becomes M or more, a defective group recording detection signal is output. This signal is output to the display circuit 11 through the OR circuit 10, and displays the detection of a defective recording surface in the same way as in the case of continuous errors. 5A is a feature of the error detection method according to the present invention, in which a defective recording surface is detected not only based on consecutive errors but also based on the number of errors. According to the embodiment shown in FIG. 1, the quality of recorded images can be detected from both the number of consecutive errors and the number of occurrences of errors, using only the output signal of the OR circuit 10. This makes it possible to more accurately inform customers that the

According to the present invention, the recorded image obtained by the customer is more accurate because there are fewer errors, and even if an error occurs in the recorded image, it can be deciphered.Furthermore, after detecting a defective recorded tooth, the code can be deciphered. Since a signal requesting transmission cancellation is sent to the transmitting side and the line is disconnected, it is possible to prevent the customer from paying unnecessary line charges.

[Brief explanation of drawings]

The figure is a block diagram of one embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Line, 2...Decoding circuit, 3...Recording circuit, 4...Continuous error line number counting circuit, 5...Continuous error line number allowable upper limit setting circuit, 6.
... Comparison/judgment circuit, 7... Number of occurrences of line errors, ?
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ees・−・・リセット信号１４・・−・−・・リセット信号１５・・−・−・・加算信号１６・・・・・・・・画データの送信中止を要求する信号代理人弁理士 薄 １ ) Toshiyuki

Claims (1)

[Claims] t In a facsimile receiving device, a first circuit that counts the number of consecutive error lines, a second circuit that sets an allowable upper limit for the number of consecutive error lines, and a second circuit that measures the number of consecutive error lines in the first circuit. a third circuit that compares and determines the allowable upper limit of the line error; a fourth circuit that counts the number of times a line error occurs;
a fifth circuit that counts the number of recorded lines and then sets an allowable upper limit for the number of line errors that occur in proportion to the number of recorded lines; and a sixth circuit that compares and determines the output of the fourth circuit with the output of the fifth circuit. An error characterized in that a seventh circuit is provided that performs a logical sum from the circuit, the output of the third circuit, and the output of the sixth circuit, and defective recorded images are detected based on the output of the seventh circuit. Detection method.