JPS61238169A - Drum scanner device - Google Patents

Abstract

PURPOSE:To observe immediately the result and to make easy and efficient the adjusting work when the level is adjusted by obtaining and displaying the average value and the standard deviation at the actual time from the digital signal of the drum scanner output. CONSTITUTION:A marker generating device 6 inputs the signal from a rotating pulse (one pulse for the drum rotation), a sampling clock, a measuring starting position setting switch 7 and a measuring period setting switch 8 from a drum scanner main body 1, and generates the marker signal (gate signal) to show the measuring period. An average value calculating part 2 and a standard deviation calculating part 3 respectively obtain the average value x=SIGMAx/n and the standard deviation sigma=SIGMAx<2>/n-x<2> of the digital signal from the digital signal of the output of the drum scanner main body 1, the sampling clock and the marker signal by the actual time. An average value displaying part 4 and a standard deviation displaying part 5 display an average value (x) and a standard deviation (delta) obtained by the actual time. At an adder 9, the marker signal is applied to the digital signal, converted to the analog signal at a D/A converting device 10 and outputted to the waveform measuring device such as the oscilloscope.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a drum scanner device connected to a computer for inputting one image data.

[Conventional technology]

The standard deviation, which represents the dispersion of data, is used as a measure of the signal-to-noise ratio of the density data output from the drum scanner, and a grayscale chart whose density values change in a stepwise manner and whose density values have been calibrated in advance is usually used as a sample. The average value and standard deviation of multiple samples of concentration data at each step are determined.

Conventionally, this standard deviation has been determined by once inputting all the data of the grayscale chart into a computer connected to the drum scanner device, and then calculating and tabulating the data on the computer.

[Problem that the invention seeks to solve]

In the conventional drum scanner device mentioned above.

All the data on the grayscale chart was input into the -H computer, and as a result of calculation and aggregation, the SN
Since the standard deviation is obtained as a ratio, there is a time delay between inputting the data and outputting the standard deviation, and when performing level adjustments etc., it takes too much time to see the adjusted results, which is inconvenient. Ta.

[Means for solving problems]

The present invention calculates and displays the average value and standard deviation in real time from the digital signal of the drum scanner output.
When performing adjustment work such as level adjustment, the result of the adjustment can be viewed immediately on the spot, making the adjustment work easier and more efficient.

That is, the drum scanner device of the present invention includes a measurement start position setting switch for setting the measurement start position on the circumference of the drum, a measurement period setting switch for setting the measurement period, and a measurement period setting switch for setting the measurement period on the drum circumference. A marker signal generator that generates a marker signal indicating the measurement period by inputting the rotation pulse, the sampling clock, and the signals from the measurement start position setting switch and measurement period setting switch, and the digital signal output from the drum scanner main body and the sampling clock. and an average value calculation unit and a standard deviation calculation unit that respectively calculate the average value and standard deviation of the digital signal from the marker signal, and an average value display unit and a standard deviation display unit that display the average value and standard deviation, respectively.
an adder that adds a marker signal to the digital signal;
It is characterized by having a D/A converter that converts a digital signal to which a marker signal is added into an analog signal.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a drum scanner device according to the present invention.

Measurement start position setting switch 7, measurement period setting switch 8
As a result, the measurement start position on the circumference of the drum at which to start calculating the average value and standard deviation, and the number of sampling clocks n that is the measurement period are given. The marker generator 6 generates rotational pulses (
A marker signal (gate signal) indicating the measurement period (start and end of measurement) is generated by inputting signals from the measurement start position setting switch 7 and measurement period setting switch 8. . The average value calculation section 2 and the standard deviation calculation section 3 calculate the average value I=Σχ of the digital signal from the output digital signal of the drum scanner body 1, the sampling clock, and the marker signal.
/n and standard deviation σ=Σχ21n−x2 are respectively determined in real time.

The average value display section 4 and standard deviation display section 5 display the average value χ and standard deviation σ obtained in real time. Adder 9 adds a marker signal to the digital signal, and D/A converter 1
0, it is converted to an analog signal and output to a waveform measuring instrument such as an oscilloscope.

Figure 2 is an example of the analog signal output waveform in Figure 1, in which a marker signal is superimposed on the grayscale signal waveform, and the operator operates the above-mentioned switches 7 and 8 while observing this waveform. You can set the interval for which you want to obtain the average value X and standard deviation σ. Among the calculations of the average value χ and standard deviation σ, calculations of ΣX and Σx2 are executed every sampling clock, and the average value χ and standard deviation σ are immediately obtained at the end of the measurement period, and the average value display section 4 and standard deviation Since they are displayed on the deviation display section 5, the operator can know the average value X and standard deviation σ of the drum scanner output signal in real time.

〔Effect of the invention〕

As explained above, the present invention calculates and displays the average value and standard deviation from the digital signal output from the drum scanner in real time, so that when performing adjustment work such as level adjustment, the adjustment results can be immediately displayed on the spot. This has the effect of making visibility adjustment work easier and more efficient.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a drum scanner device according to the present invention, and FIG. 2 is a diagram showing an example of an analog signal output waveform in FIG. 1. 1 Nidram scanner main body, 2: average value calculation section, 3: standard deviation calculation section, 4: average value display section. 5: Standard deviation display section, 6: Marker generator, 7: Measurement start position setting switch, 8: Measurement period setting switch. 9 2 adders, 10: D/A converter.

Claims (1)

[Claims] A measurement start position setting switch for setting a measurement start position on the circumference of the drum, a measurement period setting switch for setting a measurement period, and a rotation pulse and a sampling clock from the drum scanner main body. , and a marker signal generator that receives signals from the measurement start position setting switch and the measurement period setting switch and generates a marker signal indicating the measurement period, and a digital signal output from the drum scanner main body, a sampling clock, and the marker signal. an average value calculation unit and a standard deviation calculation unit that calculate the average value and standard deviation of the digital signal, respectively; an average value display unit and a standard deviation display unit that display the average value and standard deviation, respectively; A drum scanner device comprising: an adder for adding the marker signal; and a D/A converter for converting the digital signal to which the marker signal has been added into an analog signal.