JP4099284B2 - Performance control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a performance control apparatus that controls performance.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a performance control device that stores a series of musical sound waveforms and controls the performance by compressing or expanding the time axis of the stored musical sound waveforms to generate a reproduction waveform is known. As one of such performance control apparatuses, Japanese Patent Laid-Open No. 10-55180 proposes a technique for controlling swing performance. According to this technique, a musical sound waveform is stored, and when the stored musical sound waveform is divided by a cycle corresponding to a predetermined note length, the first half portion and the second half portion of the waveform in each cycle are respectively relative to each other. By reading out at a slower speed and a relatively faster speed, the time axis is expanded and compressed, and a swing is given to the reproduced musical sound.
[0003]
[Problems to be solved by the invention]
By the way, in the above publication, when a change pattern for controlling the reading speed of waveform reading is switched by a user's operation, control is performed to switch the change pattern only at a predetermined timing so that a timing that is not likely to be shifted is not shifted. Yes.
[0004]
Therefore, in the above publication, there is a problem that it is difficult to control such that the change pattern is changed immediately even if it is to be changed.
[0005]
In addition, a performance control device that includes a tempo operation element for changing the performance tempo and a depth operation element for changing the magnitude of the effect of the swing, and an operation to the operation element is immediately reflected in the performance is desired. No one has been proposed to be satisfied.
[0006]
An object of this invention is to provide the performance control apparatus which can be changed into a desired performance immediately in view of the said situation.
[0007]
[Means for Solving the Problems]
The performance control device of the present invention that achieves the above-described object provides:
(1) Waveform storage means for storing a series of musical sound waveforms. (2) Compressing or expanding the time axis of the musical sound waveforms while following the change in the control signal that indicates the level of compression / expansion that is allowed to change with time. (3) A periodic signal generating means for generating a periodic signal instructing the level of compression / expansion (4) The periodic signal generating means is controlled to change the generated periodic signal. Signal changing means to be added (5) In the periodic signal generated by the periodic signal generating means and to which the change is added, the integral value at the timing of each integer period of the periodic signal converges to 0 in each subsequent integer period. Thus, an error correction means for correcting the periodic signal is provided.
[0008]
The performance control apparatus according to the present invention changes the compression / expansion level even when the playback waveform is being generated by compressing or expanding the time axis of the musical sound waveform stored in the waveform storage means. The control signal is generated so that the error of the compression / decompression amount generated due to the level converges to zero. For this reason, even if the tempo and depth are changed, for example, performance according to the changed tempo and depth can be performed immediately. Therefore, unlike the prior art, there is no need to wait for a break between predetermined sections, and it is possible to immediately change to a desired performance.
[0009]
Here, it is preferable that the signal changing means changes the period of the periodic signal.
[0010]
With such signal changing means, even if the tempo is changed, a performance according to the changed tempo can be performed immediately.
[0011]
The tempo of the reproduction waveform by the compression / expansion means includes reproduction tempo setting means for allowing change during waveform reproduction, and the signal changing means corresponds to the tempo set by the reproduction tempo setting means. It is also a preferred form that the period of the periodic signal is changed.
[0012]
When such a playback tempo setting means and signal changing means are provided, the user can immediately change the tempo of the performance to a desired tempo by operating the playback tempo setting means during the performance.
[0013]
Furthermore, the signal changing means may change the amplitude of the periodic signal generated by the periodic signal generating means.
[0014]
With such a signal changing means, even if the depth is changed during a swing performance, for example, it is possible to perform the performance immediately with a swing effect having a magnitude corresponding to the changed depth.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0016]
FIG. 1 is a block diagram showing a hardware configuration of an embodiment of the performance control apparatus of the present invention.
[0017]
The performance control apparatus 100 shown in FIG. 1 can perform a new operation corresponding to the changed tempo and depth even when the user changes the tempo and depth by operating the operator while a certain swing performance is being performed. It is a device that can be instantly changed to a swing performance.
[0018]
The performance control apparatus 100 includes a waveform memory 10, a waveform generation means 20, a control signal generation means 30, a start / stop operator 40, a tempo operator 50, and a depth operator 60. . First, each operation element 40, 50, 60 will be described.
[0019]
The start / stop operator 40 is an operator for instructing the start or stop of the performance of a series of musical sounds. Once operated, the start / stop operator 40 outputs an “H” level start / stop signal for instructing the start of the performance. When operated, an 'L' level start / stop signal for instructing stop of the performance is output.
[0020]
The tempo operator 50 corresponds to the reproduction tempo setting means referred to in the present invention, and sets the tempo of the reproduction waveform generated by the waveform generation means 20 to be described later while allowing changes during waveform reproduction. The playback tempo information representing the tempo is output.
[0021]
The depth operator 60 is for setting the magnitude of the applied swing (depth of modulation), and outputs depth information indicating the set depth of modulation.
[0022]
Next, the waveform memory 10 will be described. The waveform memory 10 will be described with reference to FIG.
[0023]
FIG. 2 is a diagram showing a data structure of the waveform memory shown in FIG.
[0024]
The waveform memory 10 corresponds to the waveform storage means according to the present invention. The waveform memory 10 includes PCM waveform data 11 which is the waveform data body, and an original tempo 12 which is the original tempo of the PCM waveform data 11. The start address 13 and the end address 14 indicating the last address of the PCM waveform data 11 are stored.
[0025]
The waveform generation means 20 will be described with reference to FIG.
[0026]
FIG. 3 is a block diagram showing the internal configuration of the waveform generating means shown in FIG.
[0027]
The waveform generating means 20 shown in FIG. 3 includes a time axis compression / expansion processing means 21 provided with a reading means 21a, a dividing means 22, and an adding means 23.
[0028]
The time axis compression / expansion processing means 21 corresponds to the compression / expansion means referred to in the present invention, and indicates the level of compression / expansion. The PCM waveform while following the change of the control signal allowed to change with time as will be described in detail When a musical sound waveform represented by the data 11 is divided by a period corresponding to a predetermined note length, a playback waveform is generated by extending and compressing the first half and the second half of the waveform in each period, respectively. . The reading means 21a provided in the time axis compression / expansion processing means 21 reads the PCM waveform data 11, the original tempo 12 necessary for reproducing the PCM waveform data 11, etc. address), and the PCM waveform data 11 and the original tempo 12 are read from the waveform memory 10 as data.
[0029]
The dividing means 22 inputs the reproduction tempo information from the tempo operator 50 and the original tempo information from the reading means 21a, and divides "reproduction tempo information / original tempo information" to correspond to the reproduction tempo information. The “reference companding coefficient” for reproducing at the reproduction tempo is calculated. For example,
Playback tempo information = 180 BPM
Original tempo information = 100 BPM
Then,
Reference companding coefficient = 180/100 = 1.8.
[0030]
The adding means 23 adds the control signal level to the reference companding coefficient obtained by the dividing means 22 to generate a companding coefficient, and inputs it to the time axis compression / expansion processing means 21.
[0031]
Here, when a companding coefficient larger than “1” is input to the time axis compression / expansion processing means 21, the time axis compression / expansion processing means 21 compresses the PCM waveform data 11 in the time axis direction to reproduce the reproduced waveform. Is generated. Accordingly, the playback tempo is increased. On the other hand, when a companding coefficient smaller than “1” is input, the PCM waveform data 11 is expanded in the time axis direction to generate a reproduction waveform. Therefore, the playback tempo is slowed down. When “1” is input as the companding coefficient, compression and expansion are not performed, and thus a reproduction waveform is generated at the original tempo.
[0032]
Next, the control signal generating means 30 will be described with reference to FIG.
[0033]
FIG. 4 is a block diagram showing the internal configuration of the control signal generating means shown in FIG.
[0034]
4 includes a waveform table 31, a table selection unit 32, a sequence data storage unit 33, a control unit 34, an interpolation unit 35, a multiplication unit 36, an addition unit 37, Error correction means 38 is provided.
[0035]
The waveform table 31, the table selection means 32, the sequence data storage means 33, the control means 34, the interpolation means 35, and the multiplication means 36 correspond to the periodic signal generating means for generating a periodic signal indicating the compression / decompression level according to the present invention. The waveform table 31 and the sequence data storage means 33 will be described with reference to FIGS.
[0036]
FIG. 5 is a diagram showing a plurality of types of periodic waveforms stored in the waveform table, and FIG. 6 is a diagram showing sequence data stored in the sequence data storage means.
[0037]
As shown in FIG. 5, the waveform table 31 stores a plurality of types of periodic waveforms wave1, wave2, wave3, wave4,... Having different waveform shapes and periods, with a period signal for one beat as one unit. . Further, as shown in FIG. 6, the sequence data storage means 33 stores sequence data in which the order of reading a plurality of periodic waveforms wave1, wave2, wave3, wave4,. In FIG. 6, the periodic waveforms wave1, wave2, wave5,..., Wave3 are read in this order.
[0038]
A start / stop signal and reproduction tempo information are input to the control means 34 shown in FIG. Here, when 'H' level is input as a start / stop signal to the control means 34, the control means 34 refers to the sequence data stored in the sequence data storage means 33 and corresponds to the referenced sequence data. The table selection information to be output is output to the table selection means 32. Based on this table selection information, the table selection means 32 selects a periodic waveform corresponding to the sequence data stored in the waveform table 31. As a result, waveform data representing the selected periodic waveform is input to the interpolation means 35. Further, the control means 34 generates a beat timing according to the input reproduction tempo information and inputs it to an error correction means 38 described later.
[0039]
In addition to the waveform data described above, reproduction tempo information is also input to the interpolation means 35. The interpolating means 35 is an example of the signal changing means referred to in the present invention. Here, the interpolating operation is performed on the waveform data representing the selected periodic waveform at the step address corresponding to the reproduction tempo information, and the periodic waveform is obtained. The interpolation periodic signal is generated by compressing or expanding the time axis corresponding to the reproduction tempo information.
[0040]
That is, when the waveform table 31 is read with the step address corresponding to the reproduction tempo information, the read address is an address expressed in decimal point, and waveform data may not exist. For this reason, waveform data at integer addresses before and after the address are read out, waveform data at the decimal point address is generated from them by interpolation calculation, and the interpolation cycle signal is generated.
[0041]
Such a method is a publicly known method used in the sound source of an electronic musical instrument of a waveform reading type.
The waveform table 31 stores a periodic waveform of 120 BPM. Here, the step address is
Step address = playback tempo information / 120
It is calculated by the operation of For example, when the reproduction tempo information is 120 BPM, the step address is “1”, and therefore the cycle of the interpolation cycle signal is the same as the cycle of the first cycle signal. For example, when the reproduction tempo information is 60 BPM, the step address is 0.5, and therefore the cycle of the interpolation cycle signal is extended to twice the cycle of the first cycle signal.
[0042]
The multiplication means 36 receives the interpolation cycle signal generated by the interpolation means 35. The depth information from the depth operator 60 is also input. The multiplication unit 36 is an example of a signal changing unit that changes the amplitude of the periodic signal according to the present invention. Here, the multiplication unit 36 multiplies the interpolation cycle signal by a depth coefficient based on the depth information to obtain the amplitude of the interpolation cycle signal, that is, Sets the depth of modulation. As a result, the magnitude of the swing timing change can be set. In this way, a periodic signal whose period is changed by the interpolation means 35 and whose amplitude is changed by the multiplication means 36 is generated. This periodic signal is input to the error correction unit 38 via the addition unit 37.
[0043]
The process of the error correction unit 38 will be described with reference to FIGS.
[0044]
7 is a block diagram showing the internal configuration of the error correction means shown in FIG. 4, and FIG. 8 is a diagram showing operation waveforms of the performance control device shown in FIG.
[0045]
The error correction unit 38 shown in FIG. 7 includes an integration unit 38a, a flip-flop 38b (FF1), a 1 / T calculation unit 38c, a flip-flop 38d (FF2), and a conversion table 38e. Here, as shown in FIG. 8, predetermined levels of depth information and playback tempo information are output from the depth operator 60 and the tempo operator 50 provided in the performance control apparatus 100. In such a state, the start / stop operator 40 is operated, and an 'H' level is output as a start / stop signal. Then, the control means 34 (see FIG. 4) is operated, whereby a periodic signal corresponding to the depth information and the reproduction tempo information is output from the multiplication means 36. This periodic signal is input to the integrating means 38a as the signal IN via the adding means 37. The integrating means 38a integrates the waveform of the periodic signal. Here, in the first section a1, which is determined by the beat timing signal shown in FIG. 8, the expansion area (one side area) which is the first half of the waveform represented by the periodic signal and the compression area which is the second half are shown. Since the area (the area on the + side) is equal, the integral value is zero. Next, the depth operator 60 is operated in the middle of the section a2, and the modulation is set in a shallow direction. Then, the area on the + side becomes smaller than the area on one side. For this reason, an integral value of the difference between these areas is output from the integrating means 38a. This integrated value is sampled by the flip-flop 38b by a beat timing signal, and an error signal having an area of level d1 × period T1 is output in the section a3. This error signal is input to the 1 / T calculating means 38c. On the other hand, data for obtaining a period based on the reproduction tempo information is output from the conversion table 38e to the flip-flop 38d. The flip-flop 38d samples this data with a beat timing signal to obtain a cycle T1, and inputs the cycle T1 to the 1 / T calculating means 38c. The 1 / T calculating means 38c divides the error signal from the flip-flop 38b by the period T1, and feeds back the divided value (d1 / T1) to the adding means 37 as a signal OUT. The error signal (inverted (−) signal of the signal shown at the bottom of FIG. 8, that is, the + signal) input to the adding means 37 by this feedback and the periodic signal in the column of the multiplication means output shown near the center of FIG. (The output signal of the multiplier 36 in FIG. 4) is added by the adding means 37, so that the integral value including the error in the section a2 converges to 0 in the subsequent section a3.
[0046]
Next, in the middle of the section a4, the tempo operator 50 is operated this time so that the tempo is set in a fast direction. Then, the level of the reproduction tempo information is raised, and the period of the periodic signal is shortened from the middle according to this level. For this reason, the area on the + side is smaller than the area on one side of the waveform of the periodic signal in the section a4. However, in the next section a5, the value (d2 / T2) obtained in the same manner as the section a3 described above. ) Is fed back to the adding means 37 as the signal OUT, so that the error signal is canceled.
[0047]
In the above-described embodiment, the integration value at the end of the previous period is processed to converge to 0 in the next one period, but the period for performing the convergence process may be an integer period.
[0048]
FIG. 9 is a flowchart of a start processing routine executed by the control means shown in FIG.
[0049]
This start processing routine is activated by an interrupt signal generated when the start / stop operator 40 is operated to start the performance and the start / stop signal changes from the “L” level to the “H” level. . In this start processing routine, in step S11, the timer interruption of a timer (not shown) provided in the control means 34 is permitted, and this routine ends. When the timer interrupt is permitted, a timer interrupt signal is generated from the timer every predetermined time. Hereinafter, a description will be given with reference to FIG.
[0050]
FIG. 10 is a flowchart of a timer interrupt processing routine executed by the control means shown in FIG.
[0051]
In step S11 shown in FIG. 9 described above, when the timer interrupt is permitted, this routine is repeatedly executed every predetermined time by the timer interrupt signal from the timer provided in the control means 34.
[0052]
First, in step S21, it is determined whether the start / stop signal is at the "H" level or the "L" level. If it is determined that the start / stop signal is at the "H" level, the start of the performance is instructed, so the process proceeds to step S22. move on. In step S22, reproduction tempo information is input, and the process proceeds to step S23. In step S23, the reproduction tempo information is converted into step data, and step data is set as a count value in the counter.
[0053]
Next, in step S24, it is determined whether or not the count value of the counter is 1 beat value B or more. Here, the 1-beat value B indicates B that is a value that the counter should count during one beat. If it is determined that the count value is smaller than one beat value B, the time for one beat has not yet elapsed, and the process proceeds to step S30 described later. On the other hand, if it is determined that the count value is equal to or greater than 1 beat value B, the process proceeds to step S25 because the time for one beat has elapsed. In step S25, a beat timing signal having a period corresponding to the reproduction tempo information is output.
[0054]
Next, in step S26, sequence data is read from the sequence data storage means 33, and table selection information is set. Next, the process proceeds to step S27. In step S27, it is determined whether or not the sequence data has been completed. If it is determined that the sequence data has been completed, the process proceeds to step S31 to be described later in order to end the performance. If it is determined that the sequence data has not been completed, the process proceeds to step S28 in order to continue the performance. In step S28, the sequence data read address is incremented, and the process proceeds to step S29. In step S29, a value obtained by subtracting one beat value B from the count value is set as a new count value. This is to correct the difference when the count value exceeds one beat value B. In step S30, the count value is incremented by the increment data, and this routine is terminated.
[0055]
On the other hand, if it is determined in step S21 that the start / stop signal is at the “L” level, the process proceeds to step S31 in order to stop the currently performed performance.
[0056]
In step 31, the count value is set to 1 beat value B. Thereby, the beat timing signal at the next performance start can be accurately output. Next, in step S32, the sequence data read address is reset, and the process proceeds to step S33. In step S33, timer interruption is prohibited and this routine is terminated.
[0057]
In the performance control apparatus 100 of the present embodiment, the control means 34 operates in this way, and the tempo operator 50 and the depth operation are performed while the waveform generation means 20 reads out the musical sound waveform from the waveform memory 10 and performs the swing performance. Even when the playback tempo information and the depth information are changed by the child 60, the control signal generating means 30 generates a control signal so that the compression / decompression amount error based on the changed information converges to zero. , Change swing performance instantly.
[0058]
In this embodiment, the tempo operator 30 is provided, and the tempo operator 30 is operated to obtain reproduction tempo information representing a desired tempo. However, the present invention is not limited to this, and a MIDI interface is provided. The playback tempo information may be obtained through this. Alternatively, reproduction tempo information may be obtained by measuring the period of the MIDI clock.
[0059]
In this embodiment, the example of the swing performance has been described, but the present invention is not limited to this.
[0060]
【The invention's effect】
As described above, according to the present invention, it is possible to immediately respond to a desired performance, and in addition to the waveform signal performance using the performance control device of the present invention, other automatic operations are performed at the same tempo. Even in the case of performing an automatic performance by a performance device, it is possible to obtain an effect that a timing shift does not occur even if the tempo is changed or the modulation depth is changed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a hardware configuration of an embodiment of a performance control apparatus of the present invention.
FIG. 2 is a diagram showing a data structure of the waveform memory shown in FIG. 1;
3 is a block diagram showing the internal configuration of the waveform generating means shown in FIG. 1. FIG.
4 is a block diagram showing the internal configuration of the control signal generating means shown in FIG. 1. FIG.
FIG. 5 is a diagram showing a plurality of types of periodic waveforms stored in a waveform table.
FIG. 6 is a diagram showing sequence data stored in sequence data storage means.
7 is a block diagram showing the internal configuration of the error correction means shown in FIG. 4. FIG.
FIG. 8 is a diagram showing operation waveforms of the performance control device shown in FIG. 1;
9 is a flowchart of a start processing routine executed by the control means shown in FIG.
10 is a flowchart of a timer interrupt processing routine executed by the control means shown in FIG.
[Explanation of symbols]
10 waveform memory 11 PCM waveform data 12 original tempo 13 start address 14 end address 20 waveform generating means 21 time axis compression / expansion processing means 21a reading means 22 division means 23, 37 adding means 30 control signal generating means 31 waveform table 32 Table selection means 33 Sequence data storage means 34 Control means 35 Interpolation means 36 Multiplication means 38 Error correction means 38a Integration means 38b, 38d Flip-flop 38c 1 / T calculation means 38e Conversion table 40 Start / stop operator 50 Tempo operator 60 Depth Operator 100 Arithmetic control device

Claims (4)

Waveform storage means for storing a series of musical sound waveforms;
A compression / expansion means for generating a reproduced waveform by compressing or expanding the time axis of the musical sound waveform while following a change in a control signal in which a change in time is allowed, instructing a level of compression / expansion;
Periodic signal generating means for generating a periodic signal indicating the level of compression and expansion;
Signal changing means for controlling the periodic signal generating means and adding a change to the generated periodic signal;
In the periodic signal generated by the periodic signal generation means and to which the change is added, the periodic signal is corrected so that the integral value at the timing of each integer period of the periodic signal converges to 0 in the subsequent integer period. A performance control apparatus comprising: an error correction means for performing the operation. 2. The performance control apparatus according to claim 1, wherein the signal changing means changes the period of the periodic signal. Reproduction tempo setting means for setting the tempo of the reproduction waveform by the compression / expansion means to allow change during waveform reproduction is provided, and the signal changing means is configured to change the period according to the tempo set by the reproduction tempo setting means. 3. The performance control apparatus according to claim 2, wherein the period of the signal is changed. 2. The performance control apparatus according to claim 1, wherein the signal changing means changes the amplitude of the periodic signal generated by the periodic signal generating means.

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