JP3770128B2 - Waveform data editing method, waveform data editing apparatus, program, and waveform memory production method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waveform data editing method, a waveform data editing apparatus, a program, and a method for producing a waveform memory suitable for use in recording / reproducing musical sound signals, particularly ensemble sounds.
[0002]
[Prior art]
Conventionally, in a waveform memory sound source, waveform data is divided into an attack part and a loop part (or a release part if necessary). When note-on is supplied to the waveform memory sound source, the attack part is reproduced first, and then the loop part is reproduced repeatedly. Then, when note-off is supplied to the waveform memory sound source, the release unit is reproduced as necessary, and a mute process is performed.
[0003]
[Problems to be solved by the invention]
By the way, as waveform data stored in the waveform memory, audio signals (hereinafter referred to as ensemble sounds) emitted from a plurality of people or a plurality of musical instruments may be stored. In an ensemble sound, since the pitches of sounds emitted from a plurality of humans or a plurality of musical instruments are slightly different from each other, “undulation” often occurs in the ensemble sound. For this reason, for the ensemble sound, it is necessary to determine the range of the loop portion so that the “undulation” is not interrupted even if the ensemble sound is repeatedly played, and this work is complicated. In addition, by determining the range of the loop portion so that the “swell” is not interrupted, the length of the loop portion is consequently increased, and the capacity of the waveform memory mounted on the final product such as an electronic musical instrument must be increased. Did not get.
The present invention has been made in view of the above-described circumstances, and provides a waveform data editing method, a waveform data editing apparatus, a program, and a waveform memory production method capable of acquiring waveform data with less “undulation”. It is aimed. In addition, the second purpose is to make it possible to make various sounds.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is characterized by having the following configuration. The parentheses are examples.
In the waveform data editing method according to claim 1, an analysis process ( step SP4 ) for analyzing the frequency component of the input waveform data, and a fundamental component, a harmonic component and other components are selected from these frequency components. a step of identifying (step SP6), the way the fundamental tone component and the level of the overtones component among the frequency components is relatively high, the process of determining an attenuation characteristic which attenuates the other components (combo box 102 And parameter setting in the text box 104), and attenuation processes (steps SP12 to SP16) for attenuating each frequency component based on the determined attenuation characteristic, thereby obtaining output waveform data, To do.
Furthermore, in the configuration according to claim 2, in the waveform data editing method according to claim 1, in the analysis step, a power of the input waveform data is obtained by performing a fast Fourier transform process on the input waveform data. A process of obtaining a spectrum, wherein the attenuation process attenuates each component of the power spectrum on the basis of the attenuation characteristic to obtain an output power spectrum (step SP12), and is inversely fast with respect to the output power spectrum. And a process of acquiring output waveform data by performing Fourier transform processing (step SP14).
The waveform data editing apparatus according to claim 3 is characterized in that the waveform data editing method according to claim 1 or 2 is executed.
According to a fourth aspect of the present invention, the processing apparatus is caused to execute the waveform data editing method according to the first or second aspect.
The waveform memory production method according to claim 5 is a waveform memory production method for producing a waveform memory mounted on a sound source, wherein the waveform data according to claim 1 or 2 is used. The method includes a step of executing an editing method and a step of writing output waveform data obtained by the attenuation step into a waveform memory.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
1． Configuration of the embodiment
1.1. Overall Configuration The configuration of a waveform editing apparatus according to an embodiment of the present invention will be described below with reference to FIG.
Note that the waveform editing apparatus according to the present embodiment includes a general-purpose personal computer and an application program that runs on the personal computer.
In the figure, reference numeral 2 denotes a communication interface, which exchanges waveform data with other devices via a local area network. Reference numeral 4 denotes an input device, which includes a character input keyboard and a mouse. Reference numeral 6 denotes a performance operator, which includes a performance keyboard and the like.
[0006]
Reference numeral 8 denotes a display that displays various information to the user. Reference numeral 10 denotes a CPU which controls other components via the bus 16 based on a program described later. A ROM 12 stores an initial program loader and the like of the waveform editing apparatus. A removable disk drive 18 reads / writes data from / to a removable disk 20 such as a CD-ROM or MO. A waveform acquisition interface 22 converts an analog signal input from the outside into a digital signal.
[0007]
A hard disk 24 stores an operating system, a waveform synthesis application program, waveform data, and the like. Reference numeral 26 denotes a waveform output interface, which converts a digital musical tone signal supplied via the bus 16 into an analog signal. Reference numeral 28 denotes a sound system that produces the musical tone signal. A RAM 30 is used as a work memory for the CPU 10.
[0008]
2． Operation of the embodiment
2.1. Outline of Processing When waveform data of an ensemble sound is subjected to fast Fourier transform to acquire a power spectrum, peaks are generated at various points in the power spectrum. These peaks are a fundamental tone component and a harmonic component. The “swell” generated in the ensemble sound appears in the side lobes of the fundamental component and the harmonic component. Therefore, in the present embodiment, “swell” is removed from the ensemble sound by attenuating these side lobe components in the power spectrum.
[0009]
2.2. When the waveform input user starts up the waveform synthesis application program and performs a predetermined input operation, the input operation routine shown in FIG. 2 is started. In the figure, when the process proceeds to step SP 2, input waveform data such as an ensemble sound is captured via the waveform capture interface 22, and a waveform data file is generated on the hard disk 24. The waveform data file may be acquired via the communication interface 2 or the removable disk 20. When the input waveform data is acquired, the input waveform is displayed on a predetermined window on the display 8. An example is shown in FIG. Here, in the input waveform, the range of the loop portion is designated by the user. In the example shown in the figure, the highlighted part is the loop part.
[0010]
In FIG. 2A, when the processing proceeds to step SP4 next, FFT (fast Fourier transform) processing is performed on the input waveform data. Thereby, the power spectrum of the input waveform data is obtained. An example of the obtained power spectrum is shown in FIG. In FIG. 2A, when the process proceeds to step SP6 next, a fundamental tone / overtone component in the power spectrum is extracted. Note that the fundamental tone / overtone component is a place where a peak is formed in the power spectrum. These fundamental / overtone components are indicated by black circles in FIG. Further, components other than the fundamental tone / overtone components, that is, side lobe components are indicated by halftone dots in FIG. Next, when the process proceeds to step SP8, a graph as shown in FIG. 4A or 4B is displayed in a predetermined window on the display 8.
[0011]
2.3. Parameter Setting Next, when the user performs a predetermined operation in the waveform synthesis application program, a parameter setting window 100 shown in FIG. The parameter setting window 100 is for designating a parameter for attenuating the side lobe component. In the figure, reference numeral 102 denotes a removal mode selection combo box. The user can select a removal mode from “Pure”, “Triangle”, “SinWave”, and the like by operating this combo box. Here, “Pure” is a mode for uniformly attenuating components other than predetermined fundamental / overtone components. Here, FIG. 5A shows an example of the result of executing the “Pure” removal mode for the power spectrum shown in FIG. In the example shown in the figure, components other than all fundamental / overtone components, that is, side lobe components are uniformly attenuated by about “15 dB”. FIG. 5B shows an example in which the side lobe component is uniformly attenuated by about “40 dB”.
[0012]
“Triangle” is a mode in which attenuation characteristics are set in a triangular wave shape having a predetermined fundamental tone / harmonic component as a vertex (attenuation amount 0 dB). FIG. 6 shows an example in which the “Triangle” removal mode is executed for the power spectrum shown in FIG. In the figure, a triangular wave 50 drawn at the top of the power spectrum is the attenuation characteristic. In the example shown in the figure, the harmonic components are set in a triangular wave shape having all fundamental and harmonic components as vertices.
[0013]
“SinWave” is a mode in which a sinusoidal attenuation characteristic is applied instead of the triangular wave 50. “SinWave” and other removal modes are not specifically shown, but none of them attenuates the specified fundamental / harmonic components (for example, all fundamental / harmonic components), but has attenuation characteristics so as to attenuate other components. Is set. In other words, the attenuation characteristic is set so that the level of the fundamental tone / overtone component becomes relatively high.
[0014]
Returning to FIG. 3, reference numeral 104 denotes an attenuation amount setting text box, and the user can designate the maximum attenuation amount in the designated removal mode by inputting a numerical value here. Reference numeral 106 denotes a group of remaining overtone designation radio buttons, and the user can selectively designate one of the remaining modes of “All”, “Odd”, and “Even” by operating this button. . Here, “All” is a mode in which all overtone components remain, and the processing examples in FIGS. 5 and 6 described above are examples in which the “All” remaining mode is applied. “Odd” is a mode in which the odd-order overtone component remains, and the even-order overtone component is attenuated.
[0015]
“Even” is a mode in which the even-order overtone component remains, and the odd-order overtone component is attenuated. In either case of “Even” or “Odd”, the fundamental component always remains. Here, FIG. 7A shows a processing example in which the “Odd” remaining mode is applied. Also, a processing example in which the “Even” remaining mode is applied is shown in FIG. In the figure, reference numerals 52 and 54 denote attenuation characteristics in these processes. These “Even” and “Odd” remaining modes are intended to give a unique effect to the musical sound related to the input waveform data by editing the formant of the overtone component rather than eliminating the “undulation” of the input waveform data. Is.
[0016]
Returning to FIG. 3, reference numeral 108 denotes an apply button, which is a button for instructing synthesis of output waveform data by applying the above-described parameters. Reference numeral 110 denotes a cancel button, which is a button for instructing to close the parameter setting window 100. A preview button 112 is used by the user to audition the synthesized output waveform data.
[0017]
2.4. When the event process apply button 108 of the apply button 108 is clicked with the mouse, the process shown in FIG. 2B is executed. In the figure, when the process proceeds to step SP12, the power spectrum is edited based on the various parameters previously set on the parameter setting window 100, and the editing result is displayed on the display 8. Each window shown in FIGS. 5 to 7 is actually displayed on the display 8 in step SP12. Next, when the process proceeds to step SP114, an inverse FFT process is performed on the edited power spectrum. Thereby, the waveform data corresponding to the power spectrum is synthesized. The waveform data synthesized here corresponds to a loop portion in the output waveform data.
[0018]
Next, when the process proceeds to step SP16, the entire output waveform data is synthesized, and the synthesized output waveform data is stored in a predetermined output waveform data file in the hard disk 24. The contents of the synthesis process will be described again with reference to FIG. First, the length of the attack part is T1 and the length of the release part is T2 with respect to the input waveform data. The attack part of the output waveform data is synthesized by mixing the attack part of the input waveform data and the loop part of the output waveform data. The mixing ratio for both is as shown in FIGS. 8 (d) and 8 (e).
[0019]
That is, at the head portion (time t0 to t1) of the attack portion, the mixing ratio of the input waveform data is “1”, and the content of the input waveform data is used as it is as the output waveform data. During the period from time t1 to time t2, the mixing ratio of the input waveform data is gradually lowered from “1” to “0”, while the mixing ratio of the loop portion of the output waveform data is changed from “0” to “1”. It is gradually raised toward. When the attack portion of the output waveform data is stored in this way, the waveform data of the loop portion is stored for one period thereafter (in the range of time t2 to t3).
[0020]
Next, the release part of the output waveform data is synthesized by mixing the release part of the input waveform data and the loop part of the output waveform data. First, in the period from time t3 to t4, the mixing ratio of the input waveform data is gradually increased from “0” to “1”, while the mixing ratio of the loop portion of the output waveform data is “1” to “0”. It is gradually lowered toward "." After time t4, the release portion of the input waveform data is stored as it is as the release portion of the output waveform data.
[0021]
2.5. When the audition button 112 is clicked with the mouse after the output waveform data is synthesized as described above in the event processing of the audition button 112, the attack part of the output waveform data is first reproduced only once. Next, the loop portion of the output waveform data is repeatedly reproduced a plurality of times, and then the release portion of the output waveform data is reproduced only once. The reproduced output waveform data is emitted via the sound system 28. By auditioning the output waveform data in this way, the user can feel the connection between the attack part and the loop part, the connection when the loop part is repeated, the connection between the loop part and the release part, and the audibility to the input waveform data. Changes can be evaluated. Then, until a satisfactory evaluation result is obtained, various parameters are reset on the parameter setting window 100, and the output waveform data is re-synthesized.
[0022]
3． Output Waveform Data Obtained as described above is written in a waveform memory (semiconductor memory, CD-ROM, etc.) and mounted on a final product such as a sound source, an electronic musical instrument, or a synthesizer. When the output waveform data synthesized according to this embodiment is reproduced, an ensemble sound without “undulation” is reproduced, but the occurrence of “undulation” in the fundamental tone / overtone component itself is rather preferable as a sound that seems to be an ensemble sound. . Therefore, in the final product, the reproduced output waveform data is subjected to processing such as vibrato as necessary, thereby adding “undulation” to the ensemble sound while freely setting the depth and period. It will be. Further, the output waveform data obtained by applying the “Even” or “Odd” remaining mode is similarly written to the waveform memory on the final product as other waveform data having a unique effect.
[0023]
Four. Modifications The present invention is not limited to the above-described embodiments, and various modifications can be made as follows, for example.
(1) In the above embodiment, the waveform editing apparatus is realized by an application program operating on a personal computer. However, only this application program is stored in a recording medium such as a CD-ROM or a floppy disk, and distributed or transmitted. It can also be distributed through the road. Similarly, the output waveform data obtained by the waveform editing device can be stored and distributed in a recording medium such as a CD-ROM or floppy disk, or can be distributed through a transmission line.
[0024]
【The invention's effect】
As described above, according to the present invention, the output waveform data is acquired by attenuating each frequency component based on the attenuation characteristics such that the levels of the fundamental tone component and the residual harmonic component of the input waveform data are relatively high. Therefore, output waveform data with less “swell” can be obtained. Furthermore, a unique effect can be imparted to the output waveform data depending on how the attenuation characteristics are set.
[Brief description of the drawings]
FIG. 1 is a block diagram of a waveform editing apparatus according to an embodiment of the present invention.
FIG. 2 is a flowchart of a processing program in one embodiment.
3 is a view showing a display example of a parameter setting window 100. FIG.
FIG. 4 is a diagram illustrating an example of detection of fundamental / overtone components and side lobe components of input waveform data.
FIG. 5 is a diagram illustrating an example of attenuation of side lobe components in “All” remaining mode + “Pure” removal mode;
FIG. 6 is a diagram illustrating an example of attenuation of side lobe components in “All” remaining mode + “Triangle” removal mode;
FIG. 7 is a diagram illustrating an example of attenuation of side lobe components by “Odd” and “Even” remaining mode + “Triangle” removal mode;
FIG. 8 is an operation explanatory diagram of output waveform data synthesis processing;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 2 ... Communication interface, 4 ... Input device, 6 ... Performance operator, 8 ... Display, 10 ... CPU, 12 ... ROM, 16 ... Bus, 18 ... Removal disk drive device, 20 ... Removal disk, 22 ... Waveform capture interface 24 ... Hard disk, 26 ... Waveform output interface, 28 ... Sound system, 30 ... RAM, 50 ... Triangular wave, 52, 54 ... Attenuation characteristics, 100 ... Parameter setting window, 102 ... Removal mode selection combo box, 104 ... Attenuation setting Text box, 106 ... Remaining overtone designation radio button group, 108 ... Apply button, 110 ... Cancel button, 112 ... Audition button.

Claims (5)

An analysis process for analyzing the frequency components of the input waveform data;
A process of identifying a fundamental component, a harmonic component and other components from these frequency components;
As the fundamental tone component and the level of the overtones component of the frequency components is relatively high, and determining an attenuation characteristic which attenuates the other components,
A waveform data editing method comprising: attenuating each of the frequency components based on the determined attenuation characteristic, thereby obtaining output waveform data. The analysis process is a process of obtaining a power spectrum of the input waveform data by performing a fast Fourier transform process on the input waveform data,
The decay process is
Attenuating each component of the power spectrum based on the attenuation characteristics to obtain an output power spectrum;
The waveform data editing method according to claim 1, further comprising: obtaining output waveform data by performing inverse fast Fourier transform processing on the output power spectrum.   A waveform data editing apparatus for executing the waveform data editing method according to claim 1. A program for causing a processing device to execute the waveform data editing method according to claim 1. A waveform memory production method for producing a waveform memory mounted on a sound source,
A step of executing the waveform data editing method according to claim 1,
And a step of writing output waveform data obtained by the attenuation process into a waveform memory.

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