JPH086562A - Acoustic effect adding method and device therefor - Google Patents

Abstract

PURPOSE:To obtain an output wave form having a 1/f fluctuation by converting an input waveform. CONSTITUTION:Waveform data stored in a waveform data table 151 are subjected to a Fourier transformation in a Fourier transformation routine 135 to be stored in a frequency data table 152. Maximum values of logarithm of powers in respective divided areas are calculated using the frequency data to be stored in a control point data table 153. The control point data 153 are updated by a pointing device. This processing is repeated so that the logarithm between frequencies and powers becomes the inclination of -1. The frequency data 152 are changed in a fitting routine 137. The frequency data 152 are subjected to an inverse Fourier transformation in an inverse Fourier transformation routine 136 to be stored in the waveform data table 151.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for adding a sound effect to a computer, an electronic musical instrument or the like.

[0002]

2. Description of the Related Art A conventional method for adding an effect by using 1 / f fluctuation of an arbitrary acoustic signal, for example, Japanese Patent Laid-Open No. 4-119394.
The number will be described with reference to FIG.

In the figure, reference numeral 1301 is a performance section, and 130.
2 is a digital sound source section, 1303 is a modulation section, 1304 is D
/ A conversion unit, 1305 amplifier unit, 1306 speaker, 1307 effect specification unit, 1308 modulation frequency setting unit, 1309 modulation amplitude setting unit, 1310 modulation waveform generation unit, 1311 modulation waveform amplification unit, 1312 A frequency 1 / f random number generator 1313 is an amplitude 1 / f random number generator. Performance information is output from the performance section 1301, and the digital tone generator section 1302 generates a musical tone signal. Also, 1307
From 1311 to 1311, the amplitude and frequency of a periodic waveform such as a sine wave, a sawtooth wave, and a square wave are set by 1 / f random numbers that are abundant in nature to generate a modulated waveform. 130
3 from the waveforms obtained in 1302 to 1307 to 13
The modulation waveform obtained in 11 is used for modulation, and the D / A conversion unit 1
It is converted into an analog signal at 304 and output to the speaker 1306 through the amplifier 1305.

Next, a method of equalizing an acoustic signal will be described with reference to FIG. FIG. 17A shows
The frequency characteristic of a certain acoustic signal is shown. The horizontal axis represents frequency and the vertical axis represents power at each frequency. When such an acoustic signal is subjected to equalizing as shown in FIG. 17B, it is converted into a frequency characteristic as shown in FIG. 17C. That is, 2031 is the frequency characteristic of the acoustic signal after conversion, and 2032 is the frequency characteristic of the acoustic signal before conversion. As described above, the conventional method does not convert the setting as shown in FIG. 17B into the acoustic signal having the frequency characteristic as shown in FIG. 17D.

[0005]

In the above conventional method,
The input waveform generated in the digital sound source is modulated using 1 / f random numbers, and the output waveform is always 1 / f fluctuation which is abundant in nature and is comfortable for human hearing. It didn't mean that.

Further, since one musical tone is targeted, it is not possible to convert, for example, music recorded on a CD or the like into an acoustic signal having 1 / f fluctuation.

An object of the present invention is to convert an input waveform to 1 /
An object of the present invention is to provide a sound effect adding method and device for obtaining an output waveform having f fluctuation.

Another object of the present invention is to provide a sound effect adding method and apparatus capable of converting a sound signal of music recorded on a CD or the like into a sound signal having 1 / f fluctuation. .

Another object of the present invention is to provide not only 1 / f fluctuation but also a method of freely setting a frequency power spectrum pattern and converting an input waveform so as to match the spectrum pattern. Is. That is, it is an object of the present invention to provide a sound effect adding method and device for converting a setting as shown in FIG. 17B into an audio signal having a frequency characteristic as shown in FIG. 17D.

[0010]

The digitized acoustic signal is Fourier transformed, and control points representing the characteristics of this spectrum are arranged so that the logarithms of the frequencies are evenly spaced. The above object can be achieved by editing the control points so as to have 1 / f or a desired pattern, calculating spectrum data from the control points, and further performing an inverse Fourier transform.

[0011]

By directly editing the spectrum data of an arbitrary acoustic signal, it is possible to provide an acoustic effect that has many 1 / f fluctuations that are present in nature and are considered comfortable for human hearing.

[0012]

First, the operation and processing of an embodiment for converting an arbitrary acoustic signal into an acoustic signal having 1 / f fluctuation in the present invention will be described with reference to FIGS. 1, 2 and 3.

In FIG. 1, reference numerals 161 and 162 denote converters for D / A and A / D converting acoustic signals.
1 is a central processing unit (CPU) built in the computer, 10
2 is a display connected to the computer, 103 is a pointing device such as a mouse connected to the computer, 10
Reference numeral 5 is a keyboard connected to a computer, 173 is a storage device such as a hard disk connected to the computer, 174 is a speaker connected to the computer, and 131 to 140 are loaded into a memory when the software of the present invention is started on the computer. Program subroutines, 151-153
Is a data table, 181 is a D / A converter 161,
A recording / reproducing device such as a tape recorder connected to the A / D converter 162 is shown.

FIG. 2 shows a screen display example of the present invention, and FIG. 3 shows a flow chart of the present invention.

First, when the program of the present invention is activated, a screen as shown in FIG. 2 is displayed on the display 171 in the drawing routine 138. However, at startup, nothing is displayed in 222 and 223 (28 in FIG. 3).
0).

Next, the sound signal before conversion is reproduced from the recording / reproducing device 181, the record button 217 is selected by the pointing device 172, and the A / D converter 162 is selected.
In the sound input routine 131, the digitized data is loaded into the computer and the waveform data table 1
51 and display the waveform data in 222 (see FIG. 3).
281).

Next, in the Fourier transform routine 135, the waveform data 151 is Fourier transformed, converted into power data and phase data of each frequency, stored in the frequency data table 152, and the acoustic waveform data is converted into (22) in FIG.
In the display area shown in 2), the horizontal axis represents time and the vertical axis represents sound pressure fluctuation. Further, the frequency data is displayed in the display area 223 as the frequency on the horizontal axis and the power of each frequency on the vertical axis (282 in FIG. 3).

Next, in the control point calculation routine 140, the frequency data 152 is used to equally divide the horizontal axis when plotting the logarithm of frequency on the horizontal axis and the logarithm of power on the vertical axis, and dividing each area into Calculate the maximum logarithm of power. Each control point is a coordinate value in which the value of each frequency when the horizontal axis is divided is in the horizontal direction and the maximum value of the logarithm of the power of each region is in the vertical direction.
The respective control points are stored in the control point data table 153, and the control points are displayed on the display 223 (283 in FIG. 3).

Next, in the control point edit routine 139, the control device 223 is operated by the pointing device.
Select the control point 231 displayed on the screen, move to the desired position, and select the control point data 153.
Is updated and displayed again at 223 (284 in FIG. 3). This process is repeated so that the logarithm of the frequency and the logarithm of the power have a slope of -1, that is, the control points are arranged in a straight line having a slope of -1.

When the processing of 284 is completed, the fit button 218 is selected by the pointing device,
In the fitting routine 137, to fit on the line connecting the control point data 153,
The frequency data 152 is changed (285 in FIG. 3).

Next, in the inverse Fourier routine 136, the frequency data 152 is inverse Fourier transformed and stored in the waveform data 151 (286 in FIG. 3).

When the play button 216 is selected by the pointing device, the sound output routine 1
32, the waveform data 151 is transferred to the D / A converter 1
D / A conversion is performed at 61, and the signal is output from the speaker 174 (287 in FIG. 3).

If necessary, the load button 220 is selected, and in the file input routine 133, the waveform data is read from the storage device 173, and the waveform data 22 is read.
2, and the processing of 282 and 283 is performed.

Further, the save button 215 is selected to save the waveform data 151 in the storage device 173 in the file output routine 134.

Next, referring to FIG. 4, editing of control points in the process 284 of FIG. 3 will be described.

In 411 of FIG. 4A, if the button of the pointing device is pressed, the process proceeds to the process 412 and subsequent processes. If the cursor is on the Edit button (213 in FIG. 2) in process 412, the edit mode (EDITMODE) is changed in process 413. At 413, at the same time when the button is pressed, a pop-up menu as shown in FIG. 4B is displayed, and the cursor is moved to the desired mode, and then the mouse button is released to make a selection. In process 414, the cursor is moved to panel 2
If it is above 23, the process proceeds to 415 and thereafter. Process 4
If the EDITMODE is 1 at 15, point edit processing 416 for setting control points one by one is performed. When the EDITMODE is 2 in the process 417, the 1 / f region setting process 418 for setting the control point so that a certain region becomes 1 / f is performed. In the process 419, when EDITMODE is 3, a straight line region setting process 42 for setting a control point so that a certain region becomes a straight line
Perform 0.

Next, referring to FIG. 5, point editing (see FIG.
The processing 416) of 1) will be described.

In step 511 of FIG. 5A, the horizontal and vertical coordinates of the cursor indicated by the pointing device are read and stored in X1 and Y1, respectively. Process 51
In 2, the control point closest to the point (X1, Y1) is searched, and the point number is stored in C1 (FIG. 5 (b) 303). In step 513, the process waits until the button is released. In process 514, the coordinates of the cursor are read and stored in X2 and Y2, respectively (302 in FIG. 5B). In process 515, the Y coordinate of the control point C1 is updated using Y2, and the process 51
6, the control point is redrawn on the panel (223 in FIG. 2) (thick line in FIG. 5B).

Next, referring to FIG. 6, the 1 / f area setting (process 418 in FIG. 4) will be described.

In process 531 of FIG. 6A, the horizontal and vertical coordinates of the cursor indicated by the pointing device are read and stored in X1 and Y1, respectively. Process 53
In (2), the control point closest to (X1, Y1) is searched and the number of the point is stored in C1 (322 in FIG. 6 (b)). In step 533, the process waits until the button is released. In process 534, the coordinates of the cursor are read and stored in X2 and Y2, respectively. Process 5
At 35, the control point closest to (X2, Y2) is searched, and the number of the point is stored in C2.
(FIG. 6 (b) 325). In process 536, when X2 is smaller than X1, control point numbers C1 and C2
Replace. In process 537, the control points in the region from C1 to C2 are updated so that the logarithm of frequency and the logarithm of power have a slope of -1. Process 53
8, the control point is redrawn on the panel (223 in FIG. 2) (thick line in FIG. 6B).

Next, according to FIG. 7, the linear region setting (see FIG.
Processing 420) of the above.

In process 551 of FIG. 7A, the horizontal and vertical coordinates of the cursor indicated by the pointing device are read and stored in X1 and Y1, respectively. Process 55
In 2, the control point closest to (X1, Y1) is searched, and the point number is C1 (FIG. 7B).
344). In process 553, the process waits until the button is released. In process 554, the coordinates of the cursor are read and stored in X2 and Y2, respectively. In processing 555, the control point closest to (X2, Y2) is searched, and the point number is C2 (see FIG. 7).
(B) 345). In operation 556, X2
Is smaller than X1, control point number C
Swap 1 and C2. In process 557, the control points in the area from C1 to C2 are set to (X1, Y
1) (FIG. 7 (b) 341) and (X2, Y2) (FIG. 7)
(B) Update so as to line up on the line segment connecting 343). In process 558, the control point is redrawn on the panel (223 in FIG. 2) (thick line in FIG. 7B).

Next, the control point calculation routine (139 in FIG. 1) will be described with reference to FIG.

One example is shown in FIG. From the frequency data stored in the frequency data table, the horizontal axis when the horizontal axis is the logarithm of frequency and the vertical axis is the logarithm of power is equally divided. The maximum value of the logarithm of the power in each divided area is stored in the control point data table.

An example of another control point calculation routine is shown in FIG. The average value of the logarithm of the power of the frequency data included in each divided area is stored in the control point data table.

Next, the fitting routine (137 in FIG. 1) will be described with reference to FIG.

In FIG. 9A, 1101, 110
2, 1103 are edited control points, 11
Reference numeral 04 represents frequency data before fitting. a
Is the vertical coordinate of the frequency data 1104 displayed on the display. Let c be a value obtained by linearly interpolating both vertical coordinates of adjacent control points displayed on the display. Further, the real number parameter p between 0 and 1 is set, and the vertical coordinate value b displayed on the display of the converted frequency data is calculated by the following equation.

B = (ac) * p + c The above processing is performed for all frequency data, and the frequency data table is rewritten from the vertical coordinate values, and then the frequency data and the control point data are displayed on the display in the drawing routine. Is displayed. FIG. 9B shows
An example of fitting FIG. 8A at p = 0.80 is shown. FIG. 9C shows an example in which FIG. 8B is fitted with p = 0.50. FIG. 9 (d) corresponds to FIG.
An example of fitting at = 0.00 is shown.

Next, the file input / output routines 133 and 134 for reading the waveform data from the storage device and storing it in the storage device will be described with reference to FIG.

When the load button 220 shown in FIG. 2 is pressed by the pointing device, a panel as shown in FIG. 10A is displayed on the display. Reference numeral 701 denotes a directory panel showing a file hierarchical structure of the disc, and 702.
Is a list of files stored in the current directory, 703 is a panel for displaying the file selected in 702, 704 is an OK button for confirming that the selected file is stored in the waveform data table, and 705 is a waveform for the file. Indicates a cancel button that stops storing in the data table. The directory displayed in 701 is operated to move to the directory in which the desired file is stored. If there is a desired file in the directory, the file is selected in 702 and 704 is selected. At this time, the waveform data read from the file is stored in the waveform data table, and the frequency data and control point data are calculated. To cancel the file input, select 705. 704
If 705 is pressed, the panel is cleared from the display and the screen shown in Figure 2 is redisplayed.

When the save button 215 in FIG. 2 is pressed by the pointing device, a panel as shown in FIG. 10B is displayed on the display. Reference numeral 721 denotes a directory panel showing a file hierarchy structure of the disc, 72
2 is a file list stored in the current directory, 723 is a panel for inputting the name of the file to be saved, 724 is an OK button for confirming that the contents of the waveform data table are to be saved in the file, and 725 is the waveform for the file. Indicates a cancel button that stops saving the data table. Operate the directory displayed in 721 and move to the directory in which you want to save the file. Next, at 723, enter the file name and enter 72
Select 4. At this time, the contents of the waveform data table are saved in a file in the external storage device. To cancel the file output, select 725. 724 or 7
If 25 is pressed, the panel is cleared from the display and the screen shown in Figure 2 is redisplayed.

Next, referring to FIG. 11, a sound input routine for fetching a sound signal from an external sound reproducing device through an A / D converter of a computer will be described.

When the record button 217 in FIG. 2 is pressed by the pointing device, a panel as shown in FIG. 11 is displayed on the display. 751 is a level meter for displaying the volume of the sound input from the A / D converter connected to the computer, 752 is a recording start button, 753
Is a recording stop button, and 754 is a recording end button. A
Immediately before a desired sound starts from a recording / reproducing device such as an external CD or tape recorder connected to the / D converter, 752 is selected by the pointing device. After that, the waveform data sent from the A / D converter until the recording is stopped is sequentially stored in the waveform data table. When the desired sound ends, 753 is selected by the pointing device to stop recording. When the desired sound is stored in the waveform data, 754 is selected by the pointing device. At this time, frequency data and control point data are calculated. Also, the panel is cleared from the display and the screen shown in FIG. 2 is redisplayed.

Next, the waveform data table will be described with reference to FIG.

The waveform data is stored as a one-dimensional array of data as real values of the amplitude for each time step at equal intervals.

Next, the frequency data table will be described with reference to FIG.

The frequency data table is for the power (83) of each frequency obtained when the waveform data is Fourier transformed.
The values of 1) and the phase (841) are stored as two-dimensional array data.

Next, the control point data table will be described with reference to FIG.

The control data table is displayed horizontally (871) and vertically (88) when displayed on the display.
1) It is stored as two-dimensional array data as coordinate values.

Next, a second embodiment of the present invention will be described with reference to FIG.

FIG. 15 shows a block diagram of a sound effect adding apparatus in which the present invention is combined with a digital sound source section such as a synthesizer. In the figure, symbols w, f, and c marked with arrows indicate the flow of waveform data, frequency data, and control point data, respectively.

1401 is a performance section for generating performance information, and 1
Reference numeral 402 denotes a digital sound source section for generating a musical tone signal from the performance information, 1403 a Fourier transform section for converting waveform data obtained from the digital sound source section into frequency data, 140
4 is a control point calculation unit for equally dividing the horizontal axis when the frequency data is plotted with the logarithm of frequency on the horizontal axis and the logarithm of power on the vertical axis, and outputting the maximum value of the logarithm of power in each divided region. , 1405 is a control point changing unit that changes the control point so that the slope of the logarithm of frequency and the logarithm of power is -1. 1406 is a fitting unit that converts the control data into frequency data. 1407 is the frequency data. Is converted to waveform data, 1408 is a D / A conversion unit that converts the waveform data into an analog signal, 1409 is an amplifier unit that amplifies the analog signal, and 1410 is an audible acoustic signal of the amplified signal. It is a speaker that outputs as a signal.

The sound effect adding apparatus having the above components converts the tone signal so that the power spectrum of the tone signal becomes 1 / f.

[0054]

According to the present invention, the frequency characteristic of any acoustic signal can be freely adjusted by using the control point. By editing the control points so that they are aligned with a straight line with a slope of -1, it is considered comfortable for humans.
It can be converted into an acoustic signal having f fluctuation.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a sound effect adding method and device according to the present invention.

FIG. 2 is a screen configuration example.

FIG. 3 is a flow chart of the present invention.

FIG. 4 is a flowchart for editing a control point.

FIG. 5 is a flowchart for editing a control point.

FIG. 6 is a flowchart for editing a control point.

FIG. 7 is a flowchart for editing a control point.

FIG. 8 is a conceptual diagram of a control point calculation routine.

FIG. 9 is a conceptual diagram of a fitting routine.

FIG. 10 is a screen configuration diagram of a file input / output panel.

FIG. 11 is a screen configuration diagram of a sound input panel.

FIG. 12 is a waveform data table.

FIG. 13 is a frequency data table.

FIG. 14 is a control point data table.

FIG. 15 is a configuration diagram of a sound effect adding device according to a second embodiment.

FIG. 16 is a block diagram of a conventional method.

FIG. 17 is an explanatory diagram showing an example of a conventional equalizing method.

[Explanation of symbols]

101 ... Central processing unit (CPU), 102 ... Display, 103 ... Pointing device, 105 ... Keyboard, 161, ... D / A converter, 162 ... A / D converter,
173 ... Storage device, 174 ... Speaker, 181 ... Recording / playback device.

Claims (6)

[Claims] 1. A computer, a display connected to the computer, a pointing device, a speaker, and an A /
In a device provided with a D converter and a D / A converter, an input acoustic signal is taken in as digital waveform data, the waveform data is Fourier transformed to generate frequency data, and the frequency data is plotted on the horizontal axis. The logarithm of frequency and the horizontal axis when plotted with the logarithm of power on the vertical axis are equally divided, and the maximum value of the logarithm of power in each divided area is stored in the control point data table, and the logarithm of frequency and the logarithm of power are stored. The control point data is updated so that the slope becomes −1, the control data is converted into frequency data, and the data obtained by performing an inverse Fourier transform of the frequency data is stored in a waveform data table,
A sound effect adding method characterized in that the waveform data is output from a speaker by a D / A converter. 2. The frequency data is represented by a logarithm of frequency on the horizontal axis,
The horizontal axis when plotted in logarithm of power on the vertical axis is equally divided, and instead of storing the maximum value of the logarithm of power in each divided area in the control point data table, the frequency data of each divided area The sound effect adding method according to claim 1, wherein an average value of logarithms of power is stored in a control point data table. 3. The slope of the logarithm of frequency and the logarithm of power is -1.
2. The sound effect adding method according to claim 1, wherein the control point data table is edited by moving the position of the control point with a pointing device, instead of updating the control point data so that 4. The sound effect adding method according to claim 1, wherein the waveform data is read from an external storage device such as a hard disk connected to an electronic computer and stored in a waveform data table. 5. The sound effect adding method according to claim 1, wherein the waveform data stored in the waveform data table is stored in an external storage device such as a hard disk connected to an electronic computer. 6. A performance section for generating performance information, a digital sound source section for generating a musical tone signal from the performance information, a Fourier transform section for converting waveform data obtained from the digital sound source section into frequency data, and the frequency. A control point calculation unit that outputs the maximum value of the logarithm of power in each divided region by equally dividing the horizontal axis when the data is plotted with the logarithm of frequency on the horizontal axis and the logarithm of power on the vertical axis, and the control A control point changing unit that changes the point so that the logarithm of frequency and the slope of the logarithm of power are −1, a fitting unit that converts the control data into frequency data, and an inverse unit that converts the frequency data into waveform data. Fourier transform section, D / A converter section for converting the waveform data into an analog signal, amplifier section for amplifying the analog signal, and the amplifying section And a speaker that outputs the generated signal as an audible sound signal, and the sound effect adding apparatus configured so that the power spectrum of the musical sound signal becomes 1 / f.