JPS63186151A - Compressive display device for data - Google Patents

Abstract

PURPOSE:To easily find abnormality of data for a long time by extracting a maximum and a minimum value in every section of data as representative values of the section, and displaying them as a plotting sequence along a time base. CONSTITUTION:An input is an audio signal and obtained from a telephone line terminal. The input audio signal is converted by an A/D converter 1 into a digital signal, which is inputted to a memory 3 through a CPU 2. Then the data in the memory is read out under the control of the CPU 2 to extract the maximum and minimum values, which are compressed and led out to a printer 5, where they are plotted lengthwise on a rolled printer form. The operation of this system is controlled by a display and input key part 4. Thus, abnormality of the data is found extremely easily for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data compression display device, and is particularly suitable for application to a data recorder for observing waveforms of analog signals.

[Summary of the invention]

The digital data corresponding to the input waveform to be observed is divided into certain intervals, and plot strings corresponding to the maximum and minimum values are compressed and displayed along the time axis as representative values.
This is a compressed data display device that allows abnormalities in input waveforms to be detected by compressed display without displaying the waveforms of all data.

[Conventional technology]

In order to detect noise, instantaneous interruptions, etc. in telephone lines and diagnose failures, data recorders have been developed that temporarily store signal waveforms on the line and then visually display the waveforms on a display similar to a printer. . This data recorder has a word-sized memory at 60, and stores audio waveforms for about 1 minute as digital data with a sampling interval of 1 millisecond.

For display, a small printer is used to perform D/A conversion and plot the analog waveform in the longitudinal direction of the roll paper, for example.

[Problem that the invention seeks to solve]

If all the audio data for about one minute is printed out at a density of, for example, 6 dosoto/ryu, the paper for the printer will be about 10 m long, which is inconvenient to handle. Moreover, since the purpose is to check for sudden abnormal waveforms, not all of the 10 m recording is effective, and there is a lot of waste of printer paper.

In view of this problem, it is an object of the present invention to record (display) data in a compressed manner to facilitate handling and check for abnormalities.

[Means for solving problems]

The data compression display device of the present invention includes a memory (3) for storing digital data corresponding to an input waveform, and means (CPU2 ), and display means (printer 5) for displaying a plot string corresponding to these maximum and minimum values along the time axis.

[Effect]

There is a correlation between abnormalities in the input waveform (instantaneous interruption or short circuit in the signal transmission line) and amplitude changes in the sample plot sequence (difference between maximum and minimum values). Since input abnormalities can be identified from the sample plot sequence, manual abnormalities can be checked by displaying only that part of the original input waveform based on the data in the memory.

The display length of the sample plot string is significantly shorter than that of the entire waveform, so it is easy to display (print).

〔Example〕

FIG. 1 is a block diagram of a telephone line data recorder to which the data compression and display device of the present invention is applied.

The input is an audio signal, obtained from a telephone line terminal.
□Can be done. The input audio signal is converted into a digital signal by the A/D converter 1, and then sent to the memory 3 (RAM) via the CPU 2.
be taken into account. The timing of acquisition is determined by, for example, a ringing bell signal.

The data in the memory 3 is read out under the control of the CPU 2, subjected to compression processing, and then delivered to the printer 5.1.・Plotted longitudinally on a roll of printer paper. The width of the data is set to the line width of the printer, and the time axis is set to the feeding direction of the printing paper (line feeding direction). The operation of the system is controlled by the display diagram and input key 5.
This will be done in Part 4. .

FIG. 2 shows the data processing broach yard, and FIG. 3 shows the printout results. Data compression processing basically involves finding a representative value in an interval containing 4n pieces of data. That is, as shown in FIG. 2, the maximum and minimum values of n (for example, 20) consecutive A/D-converted data stored in the memory 3 are extracted, and the extracted data is divided into sections. Print out the representative value. As a result, the amount of data is compressed to 1/n, for example 1/20.

As shown on the printer paper 6 in Fig. 3, the printout is done by marking the maximum value in one section at point MAX and the minimum value at point MI.
This is a format in which each number N is plotted on the same line. Each point MAX and MIN are connected by a line. The plots of these representative values are arranged in the longitudinal direction of the printer paper 6 at a density of, for example, 6 dots/D. Therefore, if 10 m of printer paper is required to print all the data for 1 minute with the same dot density, 50 cm, which is 1/20th of that, is required.
The representative values will be printed out.

Note that if necessary, the center of the data (for example, O of the analog value)
The base line S corresponding to V) is printed as a time axis. Further, for example, a block boundary line B is printed on data 6, with words forming one block, and a series of blocks, number 7 (N), is attached to each block.

If there is no abnormality in the waveform data, the interval between points M, AX and point MIN depends on the waveform information specific to the original waveform and the compression ratio.
No major changes are observed in the dot sequence direction. If there is an abnormality in the waveform data, the intervals between the points MAX and M1, N are disturbed, such as the noise part or input missing part in FIG. 3, and it can be identified as an abnormal part.

Therefore, as shown in the flowchart of FIG. 2, a block containing an abnormal phenomenon is found based on the output results, known data serving as a verification standard, experience, etc. Then, specify block number 7 and faithfully print out the original input waveform of that part. This allows only the input abnormal portion to be easily displayed as analog waveform data.

FIG. 4 shows, as an example, an abnormal waveform and compressed sample data of an input signal at a constant DC level. The input waveform shown in (A) includes an instantaneous interruption section 8 (section where the transmission signal falls to OV) and a short circuit section 9 (short circuit section to power supply VB) of the transmission signal being measured. If we divide this waveform data into 20-word sections and represent them with their maximum and minimum values, we get (
B). When this is compressed and plotted as shown in (C), it can be seen that the amplitude (interval between the maximum value and the minimum value) of the compressed plot data changes abnormally in response to the instantaneous disconnection section 8 and the short circuit section 9. Note that in the normal part, the maximum value and the minimum value are the same.

Figure 5 shows another example of pulse-like noise IO in a sine waveform.
Indicates when the board is on the board. In the normal part, there is a significant relationship between the maximum value and the minimum value, and there is no large change between adjacent plots as in (B). However, when noise 10 is added to the section of the input waveform in A), the corresponding sample plot shows a large amplitude as shown in (B). Therefore, looking at the compressed print result (C), it is clearly seen that abnormal input (noise) has been mixed.

As mentioned above, there is a correlation between the maximum and minimum amplitude changes of the compressed sample plot and abnormalities in the input waveform, so if the correspondence of the compressed sample plot is known in advance for various human-induced abnormalities, it is possible to detect input abnormalities. can be found efficiently. It is conceivable to obtain a compressed sample plot by representing one section using one piece of data for every 20 words at regular intervals, but this would not allow abnormalities in the original input waveform to be found.

Note that instead of being printed out, it may be visually displayed on a CRT or the like, or the difference between the maximum value and the minimum value may be printed or displayed as a representative value.

Furthermore, as an application example, an automatic system may be constructed in which the CPU identifies an abnormal change in the difference between the maximum value and the minimum value for each sample section, and prints out the original waveform of the corresponding portion. .

〔Effect of the invention〕

As described above, the present invention extracts the maximum and minimum values for each certain interval of data, uses them as representative values for that interval, and displays them as a plot series along the time axis, so that abnormalities in input waveforms and correlations can be detected. A certain visual display output can be obtained in a very short display period (in the case of printing, the length of the printout). Therefore, there is no need to display (print) all the waveforms input over a long period of time, the output results are easy to handle, and abnormalities in data over a long period of time can be found very easily.

[Brief explanation of the drawing]

Fig. 1 is a system block diagram of a data recorder to which the data compression display device of the present invention is applied, Fig. 2 is an operational flowchart, Fig. 3 is a route map showing printout results, and Fig. 4
5 and 5 are waveform diagrams showing the correspondence between abnormalities in input waveforms and compressed sample plots. In addition, in the symbols used in the drawings, 1・・・−−1−−・−・・−・−・−・A/D converter 2・−−−1−−−−・−・−−−− -c p u3
−−−−−−−1−−−・−・・−・Memory 4−−−−
・−・−−−−−1−・・−Display and input key part 5−・
−−−−−−1−・・−・−Blink 6−・−・−−−
−−m−−・−Printer paper 7−−−−−−
−1−・・・・−・−Block number 8−・・・・・・−・
−・・−・−Momentary disconnection section 9−・・−・−−−1−−−−−−
. . . Short circuit part t o ----------------Noise.

Claims (1)

[Claims] A memory for storing digital data corresponding to an input waveform, a means for detecting maximum and minimum values for each section of a certain number of data read output from the memory, and a plot string corresponding to these maximum and minimum values. A data compression display device comprising a display means for displaying data along a time axis.