JPH08221060A - Musical sound element extracting device - Google Patents

Abstract

PURPOSE: To detect the correct envelope waveform of an input waveform. CONSTITUTION: The useless components of the input waveform taken out from a pickup 1 loaded on a guitar according to vibration at every string are eliminated by band-pass filters 2-1 to 2-6, and the pulse of the peak position of the input waveform is detected by pulse detector 3-1 to 3-6 to be supplied to a CPU 6. Further, the envelope of the input waveform is detected by an envelope detector to be inputted to the input terminals AD1-AD6 of the CPU 6. Then, the envelope inputted to the input terminals AD1-AD6 is converted into a digital signal at timing of an AD trigger signal outputted from an OR circuit 5 to be made an envelope waveform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a musical tone element extracting device for extracting musical tone elements such as note-on and pitch from an input waveform signal, and is particularly suitable for application to a guitar synthesizer.

[0002]

2. Description of the Related Art Heretofore, an electronic musical instrument called a guitar synthesizer has been known. In this guitar synthesizer, the vibration of a guitar string is detected by a pickup as an electric signal, and the electric signal is used as an input waveform to generate a pitch. , Note-on, note-off, etc. are detected, and the sound source is controlled by these detection signals and specified information, so that a musical sound is produced with a tone color arbitrarily specified at the pitch at which the guitar is played from the sound source. Has been made possible. Further, generally, in the conventional guitar synthesizer, the envelope detected from the input waveform is converted into a digital value at regular time intervals, and the note-on, note-off and velocity information are obtained from the converted digital value.

The pitch of the input waveform is generally detected by measuring the time between the zero crossings of the input waveform or the time between the peaks with emphasis on real-time property. Further, a guitar synthesizer is generally equipped with a pitch bend data creating means for creating pitch bend data from the difference between the detected pitch and the center pitch of the pitch name.
Created with 4 bits and supplied to the sound source.

[0004]

However, in the conventional guitar synthesizer, the envelope detected from the input waveform is converted into a digital value at regular time intervals, and the note-on, note-off and velocity information is converted from the converted digital value. The timing for every fixed time is not always the optimal timing because
The accurate envelope waveform could not be detected. Therefore, there is a problem that the musical tone element detected based on the envelope waveform cannot be detected accurately.

When the pitch of the input waveform is detected by measuring the time between zero crossings of the input waveform or the time between peaks, the input waveform generally contains harmonic components. However, if a zero-cross point other than the basic period is detected or a peak point is detected, there is a problem that an incorrect pitch is detected. In particular, this phenomenon becomes prominent for low sounds. Further, if a pitch is detected by performing a complicated process such that an erroneous pitch is not detected, there is a problem that the pitch detection takes a long time and the sound is delayed in the case of a guitar synthesizer.

Furthermore, the pitch bend data is 7
If the sound source can accept only bit data, 14
If only the upper 7 bits of the pitch bend data of bits are supplied to the sound source, there is a problem in that the intended portion of the pitch bend data cannot be accurately reflected in the musical sound generated from the sound source. by the way,
On a guitar, you may perform by performing quick picking continuously, but in this case, note-on cannot be detected because the note-on state occurs before the envelope is in the note-off state. There was a problem to say. In addition, when a signal of one system from a pickup built in the guitar is used as an input signal of the guitar synthesizer, there is a problem that the low frequency envelope becomes larger than the high frequency envelope.

Therefore, it is a first object of the present invention to provide a musical sound element extraction device capable of detecting an accurate envelope waveform of an input waveform. A second object of the present invention is to provide a musical sound extraction device capable of improving pitch detection accuracy, and to provide a musical sound element extraction device capable of detecting a pitch without delaying the sound generation time. Is the third purpose. Furthermore, it is a fourth object to provide a musical sound element extraction device capable of outputting pitch bend data that can accurately reflect the pitch bend data irrespective of the ability of the sound source. Even if you perform
A fifth object is to provide a musical sound element extraction device capable of following the performance.

A sixth object of the present invention is to provide a musical sound element extraction device capable of determining pitch data of an input waveform without a time delay, and uses a system of signals from a pickup built in a guitar. It is a seventh object of the present invention to provide a musical sound element extraction device capable of compensating for a large low-frequency envelope.

[0009]

In order to achieve the first object, the musical sound element extraction device of the present invention includes peak detection means for detecting a peak of an input waveform and outputting a peak signal, and the input waveform. Envelope detecting means for detecting the envelope of, and an analog-converting the envelope detected by the envelope detecting means into a digital signal.
Digital conversion means, and by activating the analog-digital conversion means by the peak signal output from the peak detection means, the envelope signal converted into the digital signal obtained from the analog-digital conversion means A detection means for detecting the note-on when the level exceeds the first threshold level, or a velocity detection means for detecting the velocity from the envelope converted into the digital signal is provided.

If the peak detecting means does not output the peak signal for a certain period of time after the detecting means detects the note-on, the level of the digital signal obtained by activating the analog-digital converter is detected. The determination means determines that the note-off has been made when the second threshold level is reached or lower.

In order to achieve the second object, the musical sound element extraction device of the present invention detects the peak of the input waveform and outputs the peak signal, and the time between the output peak signal. Peak-to-peak time measuring means for measuring, storage means for sequentially storing time data between peak signals measured by the peak-to-peak time measuring means, and two consecutive groups of the time data stored in the storage means. As a comparison means for calculating and comparing the total time of the time data in the group, and a total time of the time data in the group determined to be substantially equal by the comparison means is detected as the pitch of the input waveform. The pitch detecting means is provided.

Further, in the musical sound element extraction device, there is provided averaging means for calculating an average value between the groups of the total time of the time data in the groups judged to be substantially equal by the comparing means, and the averaging means. The average time data output from the means is output by the pitch detecting means, and when the pitch detected by the pitch detecting means is equal to or higher than a predetermined frequency, the detected pitch is not output. It is the one.

In order to achieve the third object, the musical sound element extraction device of the present invention comprises a periodic signal detecting means for detecting the periodic signal of the input signal, and a time measuring means for measuring the time of the periodic signal. A note-on detecting means for detecting a note-on from the input signal, and when the note-on detecting means detects a note-on, when the measurement time measured by the time measuring means is a predetermined time or more, the measurement The pitch of the input signal is fixed by using the time value of time as a basic cycle.

In order to achieve the fourth object, the musical sound element extraction device of the present invention has a pitch bend data creating means for creating pitch bend data and a mode in which all bits of the pitch bend data cannot be accepted. The pitch bend data having the acceptable number of bits is obtained by correcting the data value consisting of the upper bit group of the acceptable number of bits in the pitch bend data according to the data value of the remaining lower bit group.

In order to achieve the fifth object, the musical sound element extraction device of the present invention detects that a note-on has been made when it is detected that the level of the input waveform exceeds the first threshold level, and When the level of the input waveform signal is detected to be equal to or lower than the second threshold level, at least detection means for detecting note-off is provided, and a retrigger threshold level is provided between the first threshold level and the second threshold level. Provided,
When the level of the input waveform falls below the retrigger threshold level, and when it is detected that it exceeds the first threshold level, the detection means detects that a note-on has occurred.

In order to achieve the sixth object, the musical sound element extraction device of the present invention detects the pitch of the input waveform and outputs the pitch, and the pitch detection means for detecting the pitch output from the pitch detection means. And a pitch name determining means adapted to obtain pitch data by determining a pitch name, the pitch name determining means having a boundary value table constituted by time data which is a boundary of the pitch name of the lowest pitch. And
The pitch name is decided by octave shifting the pitch so that it falls within the range of the boundary value table.

In order to achieve the seventh object, the musical sound element extraction device of the present invention is a musical sound element for extracting a musical sound element from a one-system input waveform signal from a pickup built in a guitar through a high pass filter. It is adapted to be supplied to the element extracting means.

[0018]

According to the present invention, since the envelope waveform is obtained according to the timing of the peak detected from the input waveform, the accurate envelope waveform can be obtained. Therefore, the musical sound element can be accurately extracted. Further, according to the present invention, the accuracy of pitch detection can be improved without being affected by the harmonics contained in the input waveform. Furthermore, since pitch detection can be performed in a short time, it is possible to avoid delaying the sound generation time even when applied to a guitar synthesizer.

Further, since the upper bit value is corrected by the lower bit value of the pitch data, even if the accepted bit number of the pitch bend data is small, it is possible to accurately reflect its intended purpose. You can Further, since the retrigger threshold level is provided, even if a guitar is played by continuously performing quick picking, it is possible to extract a musical tone element from the input waveform with good followability. Furthermore, the input waveform signal of one system output from the output terminal of the guitar,
Since it is inputted to the musical sound element extracting means via the high pass filter, it is possible to compensate for the fact that the envelope signal in the low frequency band is large.

[0020]

1 is a block diagram showing a configuration in which an embodiment of a musical sound element extraction device of the present invention is applied to a guitar synthesizer.
Shown in In this figure, 1 is a pickup which is attached to a guitar and detects the vibrations of six strings by converting them into electric signals, and 2-1 to 2-6 correspond to the six strings converted into electric signals. Bandpass filters that remove unnecessary frequency components from the signal, 3-1 to 3-6 are pulse detectors that output pulses at the peak positions of the respective input waveforms corresponding to the six strings, 4-1 to 4-1 -6 is an envelope detector that detects an envelope signal from each input waveform corresponding to the six strings.

Further, 5 is an OR circuit for taking the logical sum of the pulses generated at the peak positions generated from the pulse detectors 3-1 to 3-6 and supplying it to the CPU 6, and 6 is the input pulse detector 3 Envelope detectors 4-1 to 4 according to the input capture processing for capturing the free-running counter value by the pulses output from -1 to 3-6 and the timing when the pulse from the OR circuit 5 is input.
A microprocessor (CP) that performs analog-digital conversion processing for converting the envelope signal from -6 into a digital signal and detects and outputs a musical tone element.
U) and 7 are the musical tone element signals output from the CPU 6
A MIDI interface for sending to a DI signal line, and 8 is an external sound source (MIDI device) that generates a musical sound in accordance with a musical sound element signal received via the MIDI line.
Is. It should be noted that an internal sound source 9 for generating a musical sound in accordance with the musical sound element signal output from the CPU 6 may be provided.

In the guitar synthesizer equipped with the musical sound element extracting device of the present invention having the above-described structure, the output from the pickup 1 which is attached to the guitar and is composed of six pickup elements provided corresponding to each string of the guitar. The signal waveforms are input to the bandpass filters 2-1 to 2-6 and the unnecessary frequency components are removed, so that the input waveforms output from the bandpass filters 2-1 to 2-6 are, for example, as shown in FIG. The waveform is as shown in a). This input waveform is an input waveform when the string is picked at the timing to. In this case, the pitch period of this input waveform is the time interval between the peaks shown in the figure, but in the pulse detectors 31 to 3-6 to which this input waveform is input, as shown in FIG. Pulse p at peak position
uls1, puls2, puls3, puls4 ...
Is output. This pulse is detected for every six strings and input to the CPU 6.

By the pulse input to the CPU 6,
The counter value of the free running counter provided in the CPU 6 is fetched and stored in the internal register. As will be described later, this accumulated counter value is used when detecting the pitch of the input waveform. Although this pulse is generated by detecting the negative peak position of the input waveform, it may be generated by detecting the positive peak position.

Further, envelope detectors 4-1 to 4-6
Receives the input waveform shown in FIG. 2 (a) and outputs an envelope as shown by the solid line in FIG. 2 (c). This envelope is detected for each of the six strings, and AD1 to A of the CPU 6 are detected.
It is input to the input terminals of D6. In this case, the waveform indicated by the alternate long and short dash line connecting the peak values of the envelope shown in FIG. 9C is the envelope waveform, but the portion shown in the figure is a slight time range, so there is almost no change. , A waveform that gradually approaches zero.

The pulses shown in FIG. 2B output from the pulse detectors 3-1 to 3-6 are input to the AD trigger terminal of the CPU 6 via the OR circuit 5. Then
At the timing of the pulse input to the AD trigger terminal, the envelopes input to the input terminals AD1 to AD6 of the CPU 6 are converted into digital signals.
As described later, note-on / note-off and velocity are detected by the digital value obtained by converting the envelope at the pulse timing shown in FIG. 2B.

Next, the envelope waveform is actually expressed in negative logic as shown in FIG. 3, but for the sake of understanding of the explanation, the envelope waveform will be described with reference to the envelope waveform shown in FIG. . As shown in FIG. 19, when the level of the envelope waveform exceeds the threshold level SH_ON, it is detected that the note-on has been performed, and when the level of the envelope waveform has become lower than the threshold level SH_OFF after the detection of the note-on, it is detected that the note-off has been performed. In addition, a guitar may perform a quick picking continuously, but in this case, the envelope waveform starts to rise before it becomes lower than the threshold level SH_OFF, and a note corresponding to the continuous fast picking is generated. It will not be possible to detect the on state.

Therefore, a threshold level SH_Retrigger is provided between the threshold level SH_ON and the threshold level SH_OFF.
The level of the envelope waveform is the threshold level SH_
After falling below Retrigger, when the threshold level SH_ON is exceeded, note-on is detected. However, this threshold level SH_Retrigger is equal to the threshold level SH_
Although it may be a level approximately at the center between ON and the threshold level SH_OFF, it is not a uniquely determined level but an empirically determined level. It should be noted that ST = 0, ST = 1, and ST = 2 are symbols indicating states corresponding to the description of the flowcharts described later.

Next, the operation of the guitar synthesizer equipped with the musical sound element extraction device of the present invention will be described in more detail with reference to a flow chart. FIG. 7 is a flow chart of the main routine of the CPU 6, and when the power is turned on,
The main routine is started, initialization is performed to reset various registers and the like in step S10, and then analog-digital conversion (ADC) is performed in step S20.
The ADC drive processing for performing is performed. Then, in step S30, it is determined whether or not the flag ADF is "1". The flag ADF is set to AD as described later.
It is set to "1" when the conversion is completed.

Then, the AD conversion is completed and the flag A is set.
If it is determined that DF is "1", the process proceeds to step S40 and ON / OF for detecting note-on and note-off is detected.
The F detection process is executed. Then, in step S50, velocity detection processing for detecting velocity is performed.
Furthermore, pitch detection processing is performed in step S60,
The flag ADF is set to "0" and the process returns to step S20,
The processing of steps S20 to S70 is constantly circulated. If the flag ADF is not determined to be "1" in step S30 and the AD conversion is not completed, the process returns to step S20 and the processes of steps S20 and S30 are repeatedly performed until the AD conversion is completed. .

Next, step S2 of the main routine.
FIG. 8 shows a flowchart of the ADC drive processing executed at 0. When the ADC drive processing is started, it is determined in step S100 whether the pulse shown in FIG. 2B is input to the AD trigger terminal. If it is determined that the pulse is input, it is determined in step S110 that A
DC drive is executed and the process is returned. If it is determined in step S100 that no pulse is input to the AD trigger terminal, the process proceeds to step S120.
It is determined whether or not the count value of the drive counter is 1 [ms] or more. If it is determined that the count value is 1 [ms] or more, the ADC counter is cleared in step S130 and the process proceeds to step S110. The drive is executed and returned.

Furthermore, if the count value of the ADC drive counter is not determined to be 1 [ms] or more in step S120, the process directly returns. As a result, ADC driving for AD conversion is performed 1 [ms] when a pulse is input to the AD trigger terminal and after the previous AD conversion is executed.
It will be performed when the above has passed. This is performed so that the key-off can be detected even if the input signal is attenuated to a level at which the pulse cannot be detected by the pulse detectors 3-1 to 3-6.

Next, a flow chart of the operation of the ADC incorporated in the CPU 6 is shown in FIG. When the ADC operation process is started, it is determined in step S200 whether or not there is an ADC drive command, and if it is determined that there is an ADC drive command, an AD conversion operation is performed in step S210.
Next, in step S220, the flag ADF is set to "1", and this program ends. If it is determined in step S200 that there is no ADC drive command, the process ends. Since the ADC is provided independently of the CPU unit, it operates in parallel with the execution of the CPU 6. In addition, in the AD conversion operation process of step S210, when a guitar synthesizer has six inputs, AD conversion is performed for all inputs.

The above-mentioned main routine is always circulated and executed except for the initialization process. During this process, the CPU 6 is interrupted at regular intervals to execute the timer interrupt process. A flowchart of this timer interrupt processing is shown in FIG. 10. This timer interrupt processing is performed in step S3.
At 00, the above-mentioned ADC drive counter is incremented, and a process for incrementing a pitch detection counter, which will be described later, is performed and the process is returned.

Next, step S5 of the main routine.
FIG. 11 shows a flowchart of the velocity detection process executed at 0. When the velocity detection process is started, it is determined in step S310 whether or not the pitch is fixed, and if it is determined that the pitch is fixed, the process is returned as it is. When it is determined that the pitch is not fixed, the process proceeds to step S320,
It is determined whether or not the input pulse PULS is the first pulse Pulse1 shown in FIG. 2B, and if it is determined that the pulse is the first pulse (PULS = 1), the digital signal of the envelope AD-converted in step S330. The value ADV1 is stored in the register as the velocity (VEL) and the process is returned.

ADV1 is a digital value of the envelope input to the input terminal AD1. In the case of a guitar synthesizer, since the number of strings is 6, there are 6 digital values ADV1 to ADV6. Although not performed, similar velocity detection processing is sequentially performed from ADV1 to ADV6. If it is determined in step S320 that the pulse is not the first pulse but the second and subsequent pulses, ADV1 is determined from the velocity VEL value already obtained in step S340.
Is determined to be larger. If it is determined that the value of ADV1 is larger, the digital value ADV1 is stored in the register as a new velocity (VEL) in step S330, and the process is returned. If the pitch is fixed, the process branches at step S310 and returns as it is. As a result, the maximum value among the digital values ADV1 obtained until the pitch is determined becomes the velocity (VEL).

Next, in step S40 of the main routine, the note-on and note-off detection O is executed.
A flowchart of the N / OFF detection process is shown in FIG. 12, which will be described with reference to the envelope waveform represented by the positive logic shown in FIG. When this ON / OFF detection process is started, it is detected in step S400 whether or not the status ST is "0". This status ST is shown in FIG.
9 is a flag indicating the level state of the envelope waveform, and ST = 0 indicates that the envelope waveform level is attenuated below the threshold SH_OFF level and the note-off is performed. When ST = 0 is determined, it is determined in step S410 whether the digital value ADV1 of the envelope input to the input terminal AD1 reaches or exceeds the threshold SH_ON indicating note-on.

If it is determined that the digital value ADV1 of the envelope waveform has reached the threshold SH_ON or more, the free-running pitch detection counter value is stored in the register in step S420. This counter value is incremented every time the timer interrupt processing is performed as described above. Next, in step S430, the ADC driving counter value is stored, and in step S440, PULS is "1".
In step S450, the status ST is set to "1" indicating note-on, and the process is returned. If it is determined in step S410 that the envelope waveform level ADV1 has not reached the threshold SH_ON or higher, the process directly returns.

Further, if ST = 0 is not determined in step S400, it is determined in step S460 whether ST = 1. ST = 1 indicates that note-on has been performed as described above. ST in step S460
When it is determined that = 1, PULS is set to 1 in step 470.
Then the digital value ADV1 is increased to the threshold level SH_Ret in step S480.
It is determined whether or not it has become lower than the rigger. Digital value ADV1 is threshold level SH_Retr
If it is determined that it is lower than the igger, step 4
The status ST is set to "2" at 90, and it is further determined at step S500 whether or not the digital value ADV1 becomes lower than the threshold level SH_OFF.
Here, the digital value ADV1 is the threshold level S
If it is determined that it is lower than H_OFF, it is detected that note-off has been performed, and in step S510, a note-off MIDI signal is created and output. Further, in step S520, the status ST is set to "0" indicating note-off, and the process is returned.

In step S480, the digital value ADV1 is set to the threshold level SH_Retrigger.
If it is not determined that the value is lower than r, or if the digital value ADV1 is not determined to be lower than the threshold level SH_OFF in step S500,
It will be returned as it is. Further, if ST = 1 is not determined in step S460, it is determined in step S530 whether the status ST is “2”, and ST = 2.
If it is determined that the digital value AD
It is determined whether V1 has exceeded the threshold level SH_ON.

Here, if it is determined that the digital value ADV1 exceeds the threshold level SH_ON, it is determined that note-on has been performed, and PU is determined in step S550.
LS is set to "1", then the status ST is set to "1" indicating note-on in step S560, and the process is returned. As a result, note-on can be detected even when the envelope does not fall below the note-off threshold level SH_OFF, so that note-on can be surely detected even when playing the guitar with fast picking. If it is not determined in step S540 that the digital value ADV1 exceeds the threshold level SH_ON, then PUL is determined in step S570.
S is incremented by 1 and the process proceeds to step S500, and steps S500 to S520 described above are performed.
Is performed.

Next, FIG. 13 is a flowchart of the pitch detection processing executed in step S60 of the main routine.
Shown in When the pitch detection process is started, it is determined in step S600 whether or not it is the first pulse, and the PUL
When it is determined that S = 1 and the first pulse, the pitch cannot be detected with only one pulse, so the pointer of the ring buffer is reset in step S610. It should be noted that the ring buffer is a buffer in which the count value for pitch detection is recorded.
As shown in, the address is 10 addresses from “0” to “9”, and the difference count value and mark information described later can be recorded at each position of the address. Note that P
When ULS = 1, the write pointer, read pointer, and oldest pointer are located at address "0" as shown in the figure. Here, the oldest pointer is a pointer indicating the address position of the oldest data.

Then, in step S600, PULS =
If it is not determined to be 1, in step S620, a difference count value obtained by subtracting the previous count value similarly fetched from the current count value fetched from the free running counter at the pulse generation timing is calculated. This difference count value is a value corresponding to the period between pulses, and when PULS = 2 is determined in step S630, it is recorded in the ring buffer as a pitch detection count value in step S640. Next, when it is determined in step S650 that the count value for pitch detection is equal to or lower than a certain frequency, a MIDI signal having this count value as a pitch is output and returned. That is, when the pitch is low, it takes time to detect the pitch, but by performing the above process, when the pitch is low, the pitch can be decided for the time being, and it is possible to prevent the sound generation delay.

In step S630, PULS = 2
If it is not determined, that is, if it is the third pulse or later, the process proceeds to step S670, a pattern table is created,
Then, in step S680, the pitch determination algorithm is executed. Further, it is determined in step S690 whether or not the pitch is determined. If it is determined that the pitch is determined, a MIDI signal based on the pitch is created in step S660 and the process is returned. If it is determined in step S650 that the frequency is not lower than a certain frequency, or if it is determined in step S690 that the pitch has not been determined, the process directly returns.

By the way, FIG. 14 shows a flow chart of the pattern table creation executed in step S670. When the pattern table creation process is started, step S700
At, the difference count value is written at the position of the write pointer of the ring buffer shown in FIG. Then, in step S710, the mark "1" is recorded at that position.
Next, in step S720, the mark "1" is written at the address position of the past count value which is a count value substantially equal to the current difference count value. Further, in step S730, the read (read) pointer is subtracted, the past count value is read, and when a mark other than "1" is added, the mark "2" is written at the address position of the count value.

Next, in step S740, writing is performed so that the mark at the address position having a count value substantially equal to the count value for which the mark is "2" is "2". Further, in step 750, the same operation is performed until the read pointer matches the oldest pointer, and the process is returned. As a result, the mark with the latest count is set to "1", and the mark "1", the mark "2", etc. are written by searching up to the oldest count value.

Next, FIG. 15 shows a flowchart of the pitch determination algorithm executed in step S680.
When this algorithm is started, a combination in which the sum of consecutive count values is approximately equal is searched from the count value table in step S800. This "substantially equal" means that the count value is within a predetermined numerical range or ratio range.
Then, if there are combinations that are substantially equal, it is determined in step S810 whether or not the marks are substantially aligned in the combination. Step S800
If there is no combination that is substantially equal in step S810, or if the marks are not determined to be substantially equal in step S810, the pitch is not determined in step S850 and the process is suspended and the process returns to the main routine.

If it is determined that the marks are substantially aligned, the sum of the newer count values out of the two sums of the count values is greater than or equal to the count value corresponding to a certain frequency or more in step S820. If it is determined that the frequency is not equal to or higher than a certain frequency, the average of the sums of the two count values is calculated in step S830, and the average value is determined as the pitch in step S840 and the return is made. To be done. If it is determined that the frequency is equal to or higher than a certain frequency, it is determined that the pitch one octave higher is erroneously detected, and the pitch is not determined in step S850 and is held and returned.

The pitch determination algorithm will be described by taking an example. It is assumed that ten data of time data A, B, C, ..., J as shown in FIG. 18 are written in the ring buffer. Corresponding marks are attached to these time data. As for the marks, since the same mark number is given to the data having the almost same time data from the latest data, the time data A, D, and H have the mark "1", and the time data B and I have the mark "2". , Time data C,
The mark "3" is attached to G and J, the mark "4" is attached to the time data E, and the mark "5" is attached to the time data F.

First, the process of "is there a combination in which the sums of consecutive count values are almost equal from the count value table?" In step S800. This process corresponds to the ring buffer (corresponding to the count value table) shown in FIG. Yes) continuous time data (corresponding to the count value). The investigation of the combination is performed from the latest data, and first, adjacent single time data are compared with each other to determine whether they are substantially equal or not. If it is determined that they are not almost equal, the time data adjacent to the old direction is added to the smaller time data, and the result is added to the larger time data or the older time data of the added time data adjacent to the old direction. The time data adjacent to each other in the direction is compared to determine whether they are substantially equal. The same comparison operation is performed until the oldest data is reached, and if almost no combination is found, the process proceeds to step S850 and returns.

Specifically, first, the latest data, time data A and time data B, are compared, and when it is determined that time data A is small as a result, the time data (A +
B) and the time data C are compared. As a result, when it is determined that the time data C is small, the time data (A + B) and the time data (C + D) are compared. As a result, when it is determined that the time data (C + D) is small, the time data (A + B) and the time data (C + D + E) are compared.
As a result, when it is determined that the time data (A + B) is small, the time data (A + B + C) and the time data D are compared. Furthermore, when it is determined that the time data D is small,
The time data (A + B + C) and the time data (D + E) are compared. Hereinafter, the same comparison operation is repeated. When such a comparison operation is repeated, time data (A
+ B + C) and time data (D + E + F + G) are combined, it is determined that they are substantially equal.

Then, the process proceeds to step S810, and it is judged whether or not the arrangement of the marks of the combination is the same. This judgment is made as follows. (1) Compare the numbers of the first marks. It is determined whether or not the number of marks of the other combination falls within the range of plus or minus 1 of the number of marks of the combination having the smaller number of marks. (2) In the judgment of (1), when it is within the range of plus or minus 1, it becomes “yes”, and at least the number of marks which is the number of the marks having the smaller number of marks is subtracted from the number of the marks, and the number of the marks is equal. (3) If the marks match in the judgments of (3) and (2), "yes"
s ”, and it is further determined whether or not the matched marks have the same order.

When it is judged that they are the same as the result of the judgment of the above (3), it is judged as "substantially the same" in step S810, and the process proceeds to step S820. On the other hand, in the judgments of (1), (2), and (3), “n”
When it is "o", it means that it is determined as "no" in step S810, and the process proceeds to step S850 and is returned.
Specifically, considering the combination of time data (A + B + C) and time data (D + E + F + G), the number of marks is “3” and “4”, respectively, and the smaller one is “3”.
The range of plus or minus 1 of 2 is 2 to 4, and since "4" is within that range, the determination of (1) becomes "yes" and the process proceeds to the determination of (2). In this (2), it is checked whether the numerical values of the marks match by the number "2" obtained by subtracting 1 from the number "3" of the smaller mark. Then, since the numerical values of the marks of the time data A and the time data D match with "1" and the numerical values of the marks of the time data C and the time data G match with "3", the judgment "2" also shows "yes".
s ”and the process proceeds to the judgment of (3) above.

In the judgment of (3), the order of the matched marks is examined. Combination of time data (A,
(B, C) and (D, E, F, G) coincident marks are ordered from the latest data to the oldest data in the order of "1".
→ The order is “3”. Therefore, the determination in (3) above also results in "yes", and the process proceeds to step S820. In step S820, it is determined whether or not a frequency higher than the expected frequency or a pitch one octave higher is detected as described above. For example, it is determined that the time data (A + B + C) is not higher than a certain frequency. If so, the process proceeds to step S830, the average of the two combinations, that is, the time data {(A + B + C) + (D + E + F + G)} / 2 is calculated, and this average value is determined as the pitch in step S840.

In the specific example described above, it is understood that the time data B and the time data (E + F) are almost equal. This is because a pulse is generated at the boundary between the time data E and the time data F due to a harmonic or the like, and the time data E and the time data F are
Originally, it is treated as one time data, but it is observed independently because the waveform "breaks". However, according to the pitch determination algorithm described above, even if the waveform "breaks" in this way, the original pitch can be reliably detected.

Next, MI when note-on is detected
A flowchart of the DI code creating process is shown in FIG.
When this MIDI chord creating process is started, an octave shift of the pitch determined to enter the note name boundary table is performed in step S900. This boundary value table is shown in FIG. 4, and this boundary value table is composed of count values (time data) indicating the boundary value of the lowest note name. As a result, the boundary value is set to a large count value, so that the note name can be accurately determined. Therefore, by comparing the boundary value of the boundary value table sequentially read in step S910 and the octave-shifted detected pitch, the pitch name of the pitch closer to the boundary value is detected. Is determined as Also, the octave of the detected pitch can be known from the number of octave shifts.

Then, in step S920, the difference between the octave-shifted detected pitch and the determined boundary value of the pitch name is calculated, whereby pitch bend data is created and transmitted. Then, in step S930, the velocity VEL at that time is read out, and is sent to the external sound source 8 which is a MIDI device as note-on data together with the obtained key code, and is returned. Note that the pitch bend data is usually 14-bit data, but there are cases where the pitch bend data of 14 bits cannot be received and only the pitch bend data of 7 bits is accepted due to the capability of the sound source. In such a case, since only the upper 7 bits are received, the pitch bend data is not accurately reflected in the musical sound. Further, the boundary value table shown in FIG. 4 stores therein the count value corresponding to the lowest note name and the count value corresponding to 50 cents, respectively. If the reference pitch is fixed, this table only needs to be stored as one type, but if the reference pitch can be changed, multiple boundary value tables are stored and stored in the set reference pitch. Select and use it accordingly. For example, when the reference pitch is variable in units of 1 Hz with A3 = 440 to 445 Hz, it is necessary to provide a boundary value table corresponding to 6 types of reference pitch.

Therefore, pitch bend data is created as shown in the flow chart for creating pitch bend data shown in FIG. When this pitch bend data creation processing is started, it is determined in step S1000 whether the pitch bend data is in the 7-bit mode, and
If the bit mode is determined, in step S1010, the lower 7 bits of the 14 bits are rounded and the upper 7 bits are added to the upper 8 bits to generate pitch bend data, which is output and returned. Also, 7
If the bit mode is not determined, step S102.
At 0, 14-bit pitch bend data is output as it is and returned.

Next, a modified example of the present invention is shown in FIG. 5, in which the guitar 10 is not provided with a dedicated pickup and a signal of one system extracted from the pickup built in the guitar 10 is used. This is an example of configuring a guitar synthesizer. In such a case, the signal of the low string or the signal of the high string will be mixed and output as a single signal, but the energy of the low string is high and its envelope is higher than that of the high string. Be made bigger. So, to balance the guitar 1
The signal of one system taken out from the normal terminal of 0 is passed through the high-pass filter 11 and the above-mentioned pulse detector 12
And to the envelope detector 13. This attenuates the envelope of the lower strings and balances them with the higher strings.

[0059]

As described above, according to the present invention, the envelope data is obtained according to the timing of the detected peak of the input waveform, so that the accurate envelope data can be obtained, so that the musical tone element can be accurately obtained. Will be able to extract. Further, according to the present invention, the accuracy of pitch detection can be improved without being affected by the harmonics contained in the input waveform. Furthermore, since pitch detection can be performed in a short time, it is possible to avoid delaying the sound generation time even when applied to a guitar synthesizer.

Furthermore, since the upper bit value is corrected by the lower bit value of the pitch data, the intended purpose of the pitch bend data is accurately reflected even when the number of bits of the accepted pitch bend data is reduced. be able to. Further, since the retrigger threshold level is provided, even if a guitar is played by continuously performing quick picking, it is possible to extract a musical tone element from the input waveform with good followability. Furthermore, since the one-system input waveform signal output from the output terminal of the guitar is input to the musical sound element extraction means via the high-pass filter, it is possible to compensate for the fact that the low-frequency envelope signal is large.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a guitar synthesizer to which a musical sound element extraction device of the present invention is applied.

FIG. 2 is a diagram showing a signal waveform of the guitar synthesizer shown in FIG.

FIG. 3 is a diagram showing a relationship between envelope waveforms and note-on and note-off threshold levels.

FIG. 4 is a diagram showing a boundary value table.

FIG. 5 is a block diagram showing a configuration showing a modified example of the present invention.

FIG. 6 is a diagram for explaining a ring buffer.

FIG. 7 is a flowchart of a main routine of the CPU in the musical sound element extraction device of the invention.

FIG. 8 is a flowchart of ADC drive processing in the musical sound element extraction device of the present invention.

FIG. 9 is a flowchart of the operation of the ADC in the musical sound element extraction device of the present invention.

FIG. 10 is a flowchart of timer interrupt processing in the musical sound element extraction device of the present invention.

FIG. 11 is a flowchart of velocity detection processing in the musical sound element extraction device of the present invention.

FIG. 12: ON / ON in the musical sound element extraction device of the present invention
It is a flow chart of OFF detection processing.

FIG. 13 is a flowchart of pitch detection processing in the musical sound element extraction device of the present invention.

FIG. 14 is a flowchart of a pattern table creation process in the musical sound element extraction device of the present invention.

FIG. 15 is a flowchart of a pitch determination algorithm in the musical sound element extraction device of the present invention.

FIG. 16: MID in the musical sound element extraction device of the present invention
It is a flow chart of I code creation processing.

FIG. 17 is a flowchart of pitch bend data creation processing in the musical sound element extraction device of the present invention.

FIG. 18 is a diagram showing an example of time data in a ring buffer.

FIG. 19 is a diagram showing in positive logic the relationship between the envelope waveform and the note-on and note-off threshold levels.

[Explanation of symbols]

1 pickup, 2-1 to 2-6 band pass filter, 3-1 to 3-6 pulse detector, 4-1 to 4-6
Envelope detector, 5 OR circuit, 6 CPU, 7
MIDI terminal, 8 external sound source, 9 internal sound source, 10 guitar, 11 high pass filter, 12 pulse detector,
13 Envelope detector

Claims (10)

[Claims] 1. A peak detecting means for detecting a peak of an input waveform and outputting a peak signal, an envelope detecting means for detecting an envelope of the input waveform, and an envelope detected by the envelope detecting means converted to a digital signal. The analog signal is converted into a digital signal obtained from the analog-digital conversion means by activating the analog-digital conversion means by the peak signal output from the peak detection means. A detection means for detecting note-on when the envelope level exceeds the first threshold level, or a velocity detection means for detecting velocity from the envelope converted into a digital signal. Musical sound element extraction device. 2. When the peak detecting means does not output a peak signal for a certain period of time after the detecting means detects a note-on, the level of the digital signal obtained by activating the analog-digital converter is detected. 2. The musical sound element extraction device according to claim 1, wherein the detection means detects that a note-off has been performed when the second threshold level has been reached. 3. A peak detecting means for detecting a peak of an input waveform and outputting a peak signal, a peak-to-peak time measuring means for measuring a time between the output peak signals, and a peak-to-peak time measuring means. Storage means for sequentially storing the time data between the peak signals, and the continuous time data stored in the storage means as two groups, and the total time of the time data in the group is calculated and compared. A musical sound element extraction device comprising: a comparison means; and a pitch detection means for detecting the total time of the time data in the group determined to be substantially equal by the comparison means as the pitch of the input waveform. 4. An averaging means for calculating an average value between the groups of the total time of the time data in the group determined to be substantially equal by the comparing means is provided, and an average output from the averaging means. 4. The musical sound element extraction device according to claim 3, wherein the pitch detection means outputs time data. 5. The musical sound element extraction device according to claim 3, wherein the detected pitch is not output when the pitch detected by the pitch detection means is equal to or higher than a predetermined frequency. 6. A periodic signal detecting means for detecting a periodic signal of an input signal, a time measuring means for measuring a time of the periodic signal, and a note-on detecting means for detecting a note-on from the input signal, After the note-on detection means detects the note-on, when the measurement time measured by the time measurement means is a predetermined time or more, the time value of the measurement time is used as a basic cycle to determine the pitch of the input signal. Musical sound element extraction device characterized by. 7. Pitch bend data creating means for creating pitch bend data, and a data value consisting of a high-order bit group of the number of accepted bits in the pitch bend data when all the bits of the pitch bend data are in an unacceptable mode. A tone element extraction device characterized in that pitch bend data having an acceptable number of bits is obtained by performing correction according to the data value of the remaining lower bit group. 8. A note-on is detected when the level of the input waveform exceeds the first threshold level, and a note-on is detected when the level of the input waveform signal is below the second threshold level. At least a detection means for detecting note-off is provided, a retrigger threshold level is provided between the first threshold level and the second threshold level, and the level of the input waveform is below the retrigger threshold level, A musical sound element extraction device characterized in that the detection means detects that a note-on has been performed when it is detected that the threshold value has exceeded one threshold level. 9. A pitch detecting means for detecting a pitch of an input waveform and outputting the pitch, and a pitch name determining means for obtaining pitch data by determining a pitch name output from the pitch detecting means. The pitch name determining means has a boundary value table configured by time data which is a boundary of the pitch name in the lowest note, and the pitch is octave so as to fall within the range of the boundary value table. A musical tone element extraction device characterized by determining a note name by shifting. 10. A musical sound element extraction device, characterized in that a system of input waveform signals output from a pickup incorporated in a guitar is supplied to a musical sound element extraction means for extracting musical sound elements via a high pass filter.