JP4012949B2 - Waveform editing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waveform editing method for generating edited waveform data by editing original waveform data stored in a memory.
[0002]
[Prior art and problems to be solved by the invention]
The arbitrary waveform generator stores waveform data in a waveform memory, and outputs an analog waveform signal by performing digital / analog conversion on the waveform data read from the waveform memory. An arbitrary output waveform signal can be generated by arbitrarily adjusting the contents of the waveform data stored in the memory. In this case, the operator displays the waveform data stored in the waveform memory on a display screen such as a CRT (cathode ray tube) and operates the operation panel to arbitrarily edit the shape of the displayed waveform. Waveforms can be generated.
[0003]
When executing waveform editing, an operation of specifying a part of a display waveform, shifting the specific partial waveform in the horizontal axis direction or the vertical axis direction, and displaying the enlarged or reduced image is frequently performed. In that case, a discontinuity or a blank portion of the waveform may occur due to the specific partial waveform that is shifted, enlarged or reduced, and the original waveform being overlapped or separated. In FIG. 6, a portion of the original waveform (portion from point A to point B) is shifted by ΔT in the right direction along the time axis, so that a blank portion and an overlapping portion of the display waveform are generated. That is, a point a to a point A is a blank portion, and a point b to a point B is an overlapping portion. Waveform editing is performed by arbitrarily processing such blank portions and overlapping portions of the waveform. For example, as shown in FIG. 7, when the waveforms are simply connected by straight lines, the output waveform signal Changes will not be smooth. If it is desired to change the output waveform signal smoothly and continuously, blank portions and overlapping portions of the waveform must be edited separately and connected by a smooth curve. However, such a waveform editing operation is quite complicated, and it has been time-consuming and troublesome to actually generate a desired smooth waveform.
[0004]
Accordingly, an object of the present invention is to provide a waveform editing method capable of automatically and easily generating a continuous and smooth edited waveform when editing a part of an original waveform.
[0005]
[Means for solving the problems]
The present invention, by editing the original waveform data displayed as multiple consecutive points when displayed waveform on the screen having a horizontal axis and a vertical axis, a waveform editing method is stored in the memory as the edited waveform data. According to this method, and stores the edited partial waveform data each partial original waveform data of the selected consecutive points of the original waveform data is shifted with respect to the horizontal axis or the vertical axis by a predetermined amount in the memory, on the original waveform data A first predetermined range that continues outward from one end of the partial original waveform data is set, a second predetermined range that continues outward from the other end of the partial original waveform data on the original waveform data is set, and the first predetermined range of the first predetermined range is set . The shift amount of each point of one smoothing source waveform data is calculated based on a predetermined function of the point position, and the calculation result is stored in memory as first smoothed edited waveform data that continues outward from one end of the edited partial waveform data. stored in the shift amount for each point of the second smoothing the original waveform data of the second predetermined range, and calculated based on a predetermined function of the point position, knitting the calculation result From the other end of the already partial waveform data stored in the memory as a second smoothing edited waveform data continuously to the outside. As a result, the first and second smoothed edited waveform data and the edited partial waveform data are generated as smooth edited waveform data. Note that the first and second predetermined ranges can be arbitrarily set.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 5 is a block diagram showing an example of the configuration of an arbitrary waveform generator suitable for applying the present invention. This apparatus is controlled by a microprocessor (μP) 10 via a main bus 12, and various patterns of waveform data, control software, and the like are stored in a system memory 14 including a ROM and a RAM. The operator performs various operations via the operation panel 16. The output waveform memory 18 stores arbitrary waveform data created by the operator. The display device 20 is well known to those skilled in the art, such as the contents of the output waveform memory 18 on the display screen such as a CRT (cathode ray tube) or a liquid crystal display device, and various conditions and operation modes set by the operator. Display status. The output circuit 22 converts the waveform data read from the output waveform memory 18 into an analog waveform signal and outputs it through the output terminal 24. According to the present invention, the waveform data stored in the output waveform memory 18 is read, and the operator executes waveform editing while displaying the waveform on the screen of the display device 20. Therefore, the waveform data being edited is also stored in a predetermined storage area in the output waveform memory 18, and edited waveform data is generated by using the original waveform data. How to use the original waveform data will be described later in detail. Note that an editing waveform memory may be provided as hardware different from the output waveform memory 18, and the waveform data being edited and the edited waveform data may be stored.
[0007]
FIG. 1 is a waveform diagram for explaining an example of the waveform editing method of the present invention. The horizontal axis is a time axis (each time value corresponds to each address value in the memory), and the vertical axis is a voltage axis representing the voltage value at each point. One address on the time axis corresponds to one point of data, and one waveform data is composed of a data group such as 512 points or 1024 points. It should be noted that the waveform editing in FIG. 1 corresponds to the waveform editing in the conventional example in FIG. 6 for the convenience of explanation. That is, it shows a case where the waveform from point a (address value: m) to point b (address value: n) of the original waveform is shifted by ΔT in the right direction along the time axis. The portion of the original waveform from point a to point b is denoted as partial original waveform (ab), and after shifting rightward by ΔT to point A (address value: m + ΔT) to point B (address value: n + ΔT) ) Are represented as edited partial waveforms (A to B). In FIG. 1, since all the points of the partial original waveforms (a to b) are shifted by ΔT, the edited partial waveforms (A to B) are represented by waveforms having the same shape. Note that the waveforms of the partial source waveforms (ab) are not displayed for convenience.
[0008]
As described above, when the partial original waveform (ab) is moved to the edited partial waveform (AB), the point a and the point A are separated on the time axis, and the point b and the point B are separated. The interval will overlap on the time axis. Therefore, according to the present invention, in order to smoothly connect the original waveform and the edited partial waveform (A + B), the waveform data from the point a to the point c of the original waveform is used and the point A to the point c are used. Waveform data that smoothly connects up to is automatically calculated. Similarly, waveform data that smoothly connects point B to point d is automatically calculated using waveform data from point b to point d of the original waveform. As a result, smooth curve portions (c to A) and (B to d) as shown by bold lines in FIG. 1 are automatically obtained, so that the operator selects an arbitrary portion of the original waveform, By simply shifting in the time axis direction, both ends of the shifted waveform portion and the original waveform are automatically and smoothly connected, so waveform editing can be performed very easily and quickly.
[0009]
In FIG. 1, a time axis region from a point c (address value: m−sm) to a point A (address value: m + ΔT) is referred to as a first smoothing region. The time axis region from the point B (address value: n + ΔT) to the point d (n + ΔT + sm) is referred to as a second smoothing region. The range of the first and second smoothing regions can be arbitrarily set by selecting the value of sm. The partial waveforms (c to A) and (B to d) of the first and second smoothing regions indicated by bold lines in FIG. 1 are obtained from the partial waveform data of (c to a) and (b to d) of the original waveform, respectively. These are obtained by automatic calculation and are called a first smoothed edited waveform and a second smoothed edited waveform, respectively. For example, the data of the point f on the first smoothed edited waveform (c to A) is obtained by calculating the data of an arbitrary point e on the partial waveform (c to a) of the original waveform with a predetermined function. . That is, the vertical axis coordinate values of the point e and the point f are the same, and when the difference of the horizontal axis coordinate value (address value) between the point e and the point f is represented by the variable y, the variable y is A predetermined cubic function of the axis coordinate (address value) x is assumed.
[0010]
FIG. 2 is a diagram for explaining a method of calculating the first and second smoothed edited waveform portions corresponding to the case of FIG. The horizontal axis represents the address value (variable x) of the original waveform data corresponding to the time axis, and the vertical axis represents the address shift amount (variable y) from the original waveform data to the edited waveform data. That is, all points in the portion of the original waveform from point a (address value: m) to point b (address value: n) are shifted by ΔT, and edited partial waveforms (A to B from point A to point B). ). In the present invention, since it is necessary to obtain a curve that smoothly connects point c to point A, the curve to be obtained touches the x-axis at point c, and the slope is such that the point A smoothly connects to line segment AB. It must be the same as line segment AB. In FIG. 2, the line segment AB is a horizontal line segment. However, when a part of the original waveform is enlarged or reduced, the address shift amount at the continuous points of the partial waveform is changed according to the enlargement ratio or the reduction ratio. Therefore, there may occur a case where the line segment AB is inclined or a curve AB. Therefore, the function of the curve that smoothly connects the point c and the point A is that the point c touches the x-axis and the point A has a slope that matches the slope at the point A of the line segment (or curve) AB. Condition. A simple function that satisfies this condition can be uniquely determined by a cubic equation. That is, a cubic equation that touches the x-axis at the x-coordinate point x0 and passes through the point (x1, y1) with a slope K is expressed by the following equation 1.
[Expression 1]
y = p * (x−x0) * (x−x0) * (x−q)
However,
p = {K * (x1-x0) -2 * y1} / (x1-x0) ** 3
q = x1-y1 * (x1-x0) / {K * (x1-x0) -2 * y1}
Here, “*” represents multiplication, “**” represents power, and “/” represents division.
[0011]
Of course, when the line segment AB is a horizontal straight line as shown in FIG. 2, the slope K at the point A is zero. In order to apply the above formula 1 to the case of FIG. 2, it can be easily applied only by substitution as in the following formula 2.
[Expression 2]
x0 = (m-sm)
x1 = m
y1 = ΔT
Similarly, the data of each point of the second smoothing waveform from the point B to the point d in FIG. 2 can be easily obtained from the calculation of the cubic equation. As shown in FIG. 2, when the slope at the point A is zero, it is not always necessary to employ the above-mentioned cubic function. For example, a cosine wave function or a sine wave function is employed. You may do it.
[0011]
FIG. 3 is a diagram showing an example of another embodiment according to the present invention. In FIG. 3, when the partial waveform (a-b) of the original waveform is translated by ΔV in the vertical axis (voltage axis) direction, the points at both ends of the edited partial waveform (A-B) after the parallel movement are obtained. A case where A and point B are smoothly connected to point c and point d on the original waveform is shown. Here, it should be noted that the partial waveforms (ab) on the original waveform are not shown, but have the same shape as the edited partial waveforms (AB) after the partial waveform is translated. Further, since the partial waveforms (ab) on the original waveform are translated in the vertical axis direction, each point on the original partial waveform (ab) and each of the edited partial waveforms (AB) are displayed. Each point corresponds to the same address value. Here, the range from the point a (address value: m) to the point c (address value: m−sm) is defined as the first smoothing region, and the point b (address value: n) to the point d (address value: n + sm). Is a second smoothing region. These first and second smoothing regions can be arbitrarily set by adjusting the address range of “sm”. The curved portion indicated by a thick line from the point A at one end of the edited partial waveform (A to B) to the point c on the original waveform is the first smoothed edited waveform (A to c). Similarly, the curve portion indicated by the bold line from point B to point d is the second smoothed edited waveform.
[0012]
In FIG. 3, when the voltage shift amount from the point e on the original partial waveform (ac) to the corresponding point f on the first smoothed edited waveform (Ac) is Z, the voltage shift amount Z is It is given by calculating with a predetermined function of the address value X on the horizontal axis. As a result, the first smoothed edited waveform (A to c) connects point A to point c with a smooth curve. Similarly, the second smoothed edited waveform (B to d) from the point B to the point d is also a predetermined function from the address value X of each point on the original waveform portion (b to d) from the point b to the point d. The point B to the point d are automatically connected by a smooth curve indicated by a thick line. Here, various functions for calculating the first and second smoothed edited waveforms can be considered. For example, a cubic function employed in the case of FIGS. 1 and 2 may be used, or a sine wave function, a cosine wave function, or the like may be used.
[0013]
FIG. 4 is a diagram showing the relationship between the voltage shift amount Z and the address value X of the first and second smoothed edited waveforms in FIG. Since all the points of the edited partial waveform (A to B) are uniformly translated by ΔV from the corresponding points of the original waveform portions (a to b), in FIG. expressed. On the other hand, the first smoothed edited waveform (A to c) indicated by the bold curve is automatically generated by a predetermined function in which the voltage shift amount Z changes so that the points A to c are connected by a smooth curve. Is calculated. Similarly, the second smoothed edited waveform (B to d) is automatically calculated according to a predetermined function so as to smoothly connect the points B to d. In the example of FIG. 4, a cosine function is employed as the predetermined function. Of course, a cubic function as described above may be used, or a sine function or other appropriate function may be used.
[0014]
In FIG. 4, when the X coordinate of the point c is X1 and the X coordinate of the point A is X2, the voltage shift amount Z on the first smoothed edited waveform (A to c) is expressed by the following Equation 3. .
[Equation 3]
Z = ΔV * {cos [(X−X2) * π / (X2−X1)] + 1} / 2
In order to apply Equation 3 to FIGS. 3 and 4, the following Equation 4 may be substituted.
[Expression 4]
X1 = m-sm
X2 = m
[0015]
Similarly, the second smoothed edited waveform (B to d) of FIG. Here, the X coordinate of the point B is X3, and the X coordinate of the point d is X4.
[Equation 5]
Z = ΔV * {cos [(X−X3) * π / (X4−X3)] + 1} / 2
Similarly, substitution is performed as in the following Equation 6.
[Formula 6]
X3 = n
X4 = n + sm
[0016]
As described above, according to the present invention, when a part of the original waveform is moved in the horizontal axis direction or moved in the vertical axis direction, the gap between the original waveform and the moved waveform is automatically set. Since the waveform data of smoothly connected curves can be calculated, a smooth waveform can be easily and quickly edited and generated, and a waveform editing method with extremely excellent operability is provided.
[0017]
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and corrections can be made without departing from the gist of the present invention. It will be apparent to those skilled in the art. In particular, it should be noted that the above-described cubic function, cosine function, and the like are merely examples, and the present invention is not limited to these functions.
[Brief description of the drawings]
FIG. 1 is a waveform diagram for illustrating a waveform editing method of the present invention.
FIG. 2 is a diagram for explaining a method of calculating first and second smoothed edited waveform portions corresponding to the case of FIG. 1;
FIG. 3 is a waveform diagram for illustrating another example of the waveform editing method of the present invention.
FIG. 4 is a diagram for explaining a method of calculating first and second smoothed edited waveform portions corresponding to the case of FIG. 3;
FIG. 5 is a block diagram showing an example of the configuration of an arbitrary waveform generator suitable for using the present invention.
FIG. 6 is a waveform diagram showing an example when a part of an original waveform is moved in the horizontal axis direction in a conventional waveform editing method.
7 is a waveform diagram showing an example when the original waveform and the moved waveform portion are connected by a straight line in the case of FIG. 6;
[Explanation of symbols]
(A to c) First smoothed edited waveform (A to B) Edited partial waveform (B to d) Second smoothed edited waveform

Claims (1)

Edit the original waveform data displayed as multiple consecutive points when displayed waveform on the screen having a horizontal axis and a vertical axis, a waveform editing method for storing in the memory as the edited waveform data,
The edited partial waveform data in which each of the partial original waveform data of selected continuous points of the original waveform data is shifted by a predetermined amount with respect to the horizontal axis or the vertical axis is stored in the memory,
A first predetermined range that continues outward from one end of the partial original waveform data on the original waveform data is set,
A second predetermined range that is continuous outward from the other end of the partial original waveform data on the original waveform data is set,
A shift amount of each point of the first smoothing source waveform data in the first predetermined range is calculated based on a predetermined function of the point position, and the calculation result is continuously output from one end of the edited partial waveform data to the outside . One smoothed edited waveform data is stored in the memory,
The shift amount of each point of the second smoothing source waveform data in the second predetermined range is calculated based on a predetermined function of the point position, and this calculation result is continuously output from the other end of the edited partial waveform data. Store in the memory as second smoothed edited waveform data,
A waveform editing method, wherein the first and second smoothed edited waveform data and the edited partial waveform data are generated as smooth edited waveform data.

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