JP3731476B2 - Waveform data analysis method, waveform data analysis apparatus, and recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waveform data analysis method, a waveform data analysis apparatus, and a recording medium that are suitable for automatic performance in personal computers, electronic musical instruments, amusement devices, and the like, particularly for automatic accompaniment.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a technique for recording a natural instrument sound or the like having a certain length and automatically and repeatedly reproducing it at a speed corresponding to a set tempo is known. This technique is used for automatic accompaniment of rhythm sounds and the like, but it is necessary to compress or expand the original waveform according to a set tempo. In order to execute such processing, the following apparatuses or software are conventionally known.
[0003]
(1) Sampler
A sampler samples an analog waveform and converts it into digital waveform data. It is known to record a single sound waveform and record a phrase waveform composed of multiple sounds. The latter is especially called a phrase sampler.
[0004]
(2) Slicer
The slicer assigns note numbers to the separated waveform data in order from the beginning, and automatic performance information consisting of the assigned note number and timing (separation position), that is, sequence data for driving the separated waveform data Is generated and stored. Based on this automatic performance information, when the automatic performance is performed at the tempo at the time of recording and the waveform data separated by the reproduced note-on event is triggered, the original waveform data (the waveform data before the division) is reproduced. Here, if the tempo is changed, the timing of the note-on event changes according to the tempo, and the waveform data as a whole is expanded or contracted in the time axis direction.
[0005]
(3) Sequencer
The sequencer reproduces the sequence data. However, not only the sequence data is reproduced as it is, but also the sequence data can be reproduced at a desired tempo by appropriately increasing / decreasing the reproduction speed. Of course, it is possible to independently change the reproduction timing of each unit waveform data by editing the sequence data in advance. When this sequence data is supplied to an appropriate sound source, a musical sound waveform based on the reproduction sequence data is reproduced.
[0006]
Next, the state of the reproduced musical sound waveform will be described in more detail with reference to FIGS. 2 (a) and 2 (b).
FIG. 5A shows original waveform data in which natural musical instrument sounds and the like are recorded in stereo. When this original waveform data is divided at the rising edge of the envelope (broken line portion in the figure, hereinafter referred to as “control point”), for example, as shown in FIG. ) It can be divided into 1r to 12r. When performing automatic rhythm accompaniment or the like using the original waveform data, if the original waveform data is reproduced at the same tempo as when the original waveform data was recorded, the original waveform data may be reproduced repeatedly without any particular processing.
[0007]
If the tempo during playback is faster than during recording, it is necessary to shorten the playback portion of each original section 1r-12r. For this purpose, the end portion of each section may be cut at a certain rate. For example, if the tempo at the time of recording is “100” and the tempo at the time of reproduction is “125”, the end portions of the original sections 1r to 12r may be cut by 20% and the remaining waveform data may be reproduced.
[0008]
On the other hand, a problem arises when the playback tempo is slower than the recording tempo. That is, if the playback start timing of each section is simply delayed in accordance with the tempo at the time of playback, a silent section is generated in the gap between the sections, which is annoying. Therefore, it is general that the gap between the sections is reproduced by adding the waveform data of the immediately preceding section by a necessary length. At that time, the initial value of the amplitude of the part to be added is set to coincide with the amplitude of the part immediately before.
[0009]
[Problems to be solved by the invention]
Here, a new track is added to some originally existing sequence data (original sequence data) such as automatic performance information, and the sequence data (additional sequence data) obtained by the above technique is written to the added track. Assume that the sequence data (synthesis sequence data) of the ensemble is created.
[0010]
Here, since the original sequence data and the additional sequence data are recorded without being related to each other, if the additional sequence data is simply written on a new track, there arises a problem that the timing of both is shifted. For this reason, it is necessary to carefully adjust both timings, which is very complicated. In particular, when the tempo of the original sequence data is changing in the middle, it is necessary to perform timing adjustment everywhere in the music. Conventionally, since the waveform data is divided based only on the break position obtained by analyzing the envelope of the waveform data, the break position may be erroneously detected or may be divided at a musically inappropriate position. there were.
[0011]
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a waveform data analysis method, a waveform data analysis apparatus, and a recording medium that can record waveform data in association with original sequence data.
[0012]
[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.
  2. The waveform data analysis method according to claim 1, wherein a process of starting reproduction of automatic performance information, a process of starting recording of waveform data, and a timing relationship between the automatic performance information and the waveform data are shown. Recording the waveform data while recording synchronization control data, obtaining the envelope level of the waveform data,The automatic performance information;It has a delimiter position detection process (steps SP106 to SP118) for obtaining a delimiter position (control point) of the waveform data based on the synchronization control data and the envelope level.
  Furthermore, in the configuration according to claim 2, in the waveform data analysis method according to claim 1, the separation position detection process (steps SP106 to SP118) is based on the automatic performance information and the synchronization control data. An estimation process for determining an estimated break position (reference position) of the waveform data, a detection process for detecting one or more rising positions of the waveform data within a predetermined range corresponding to the estimated break position, and detection And an extraction process of extracting any one of the one or a plurality of rising positions as a delimiter position.
  Furthermore, in the configuration according to claim 3, in the waveform data analysis method according to claim 2, the predetermined range (detection window) includes first and second predetermined ranges, and the extraction process includes With respect to rising positions belonging to the first predetermined range, the rising positions are divided on the condition that a level value (peak level) corresponding to each of the rising positions exceeds a predetermined first threshold value (threshold value Th1). The second threshold value (threshold value) is extracted as a position and the level value (peak level) corresponding to each of the rising positions belonging to the second predetermined range is lower than the first threshold value (threshold value Th1). It is a process of extracting the rising position as the separation position on condition that Th2) is exceeded.
  Furthermore, in the configuration according to claim 4, in the waveform data analysis method according to claim 2, the estimation process is performed based on the beat timing, note-on timing, or note-off timing of the automatic performance information. The estimated delimiter position of data is determined.
  Furthermore, in the configuration according to claim 5, in the waveform data analysis method according to claim 2, the extraction process uses any rising position as the separation position based on the intensity of the detected rising position. It is characterized by extracting.
  The waveform data analysis method according to claim 6, wherein the process of starting reproduction of automatic performance information, the process of starting recording of waveform data, and the timing relationship between the automatic performance information and the waveform data Recording the waveform data while recording the synchronization control data indicating, determining the estimated beat position based on the beat timing of the automatic performance information and the synchronization control data, and based on the estimated beat position And a delimiter position determining step for obtaining a delimiter position of the waveform data.
  The waveform data analysis method according to claim 7, wherein a process of starting reproduction of automatic performance information, a process of starting recording of waveform data, and a timing relationship between the automatic performance information and the waveform data Recording the waveform data while recording the synchronization control data indicating, the process of determining the estimated rising position based on the note-on timing of the automatic performance information and the synchronization control data, and the estimated rising position And a delimiter position determining process for determining a delimiter position of the waveform data based on the waveform data.
  The waveform data analysis method according to claim 8, wherein a process of starting reproduction of automatic performance information, a process of starting recording of waveform data, and a timing relationship between the automatic performance information and the waveform data. The process of recording the waveform data while recording the synchronization control data indicating, the process of determining the estimated separation position based on the automatic performance information and the synchronization control data, and the estimated separation position in the waveform data The method includes an analysis process for analyzing a neighboring portion, and a delimiter position determination process for obtaining a delimiter position of the entire waveform data based on the analysis result.
  Furthermore, in the configuration according to claim 9, in the waveform data analysis method according to claim 8, the analysis process is a process of detecting a rising position by analyzing an envelope of the waveform data. And
  Furthermore, in the configuration according to claim 10, in the waveform data analysis method according to claim 8, the delimiter position determination step is performed for each estimated delimiter position based on a plurality of rising positions included in the analysis result. One delimiter position is determined.
  Furthermore, in the configuration according to claim 11, in the waveform data analysis method according to any one of claims 1 to 10, the tempo clock of the automatic performance for reproducing the automatic performance information and the sampling period of the waveform data are The synchronization control data includes timing data indicating recording start timing of the waveform data.
  Furthermore, in the configuration according to claim 12, in the waveform data analysis method according to any one of claims 1 to 10, the synchronization control data includes timing data indicating a recording start timing of the waveform data; A tempo clock for automatic performance and synchronization data for synchronizing the sampling period of the waveform data are included.
  The waveform data analysis apparatus according to claim 13 is characterized in that the waveform data analysis method according to any one of claims 1 to 12 is executed.
  The computer-readable recording medium according to claim 14 stores a program for causing a computer to execute the waveform data analysis method according to any one of claims 1 to 12.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
1. Hardware configuration of the embodiment
Next, the hardware configuration of the waveform editing system according to the embodiment of the present invention will be described with reference to FIG. The waveform editing system includes an application program and a driver that operate on a general-purpose personal computer.
[0014]
In the figure, reference numeral 102 denotes a display that displays various types of information to the user. Reference numeral 104 denotes an operator, which includes a keyboard and a mouse. Reference numeral 106 denotes a microphone that detects a musical sound signal (analog waveform) of a natural musical instrument or the like. Reference numeral 108 denotes an AD converter, which samples the analog waveform and converts it into a digital signal. A recording circuit 110 directly accesses the hard disk 112 (performs a DMA operation) and stores the digital signal in the hard disk 112 as waveform data. In addition to these waveform data, the hard disk 112 stores a general-purpose personal computer operating system, a waveform editing application program described later, and the like.
[0015]
A reproduction circuit 114 directly accesses the hard disk 112 (performs a DMA operation), reads waveform data to be reproduced, and supplies the waveform data to the mixer 116. A sound source 122 synthesizes musical tone signals based on performance information supplied via the bus line 136 and supplies the synthesized musical tone signals to the mixer 116. In the mixer 116, the waveform data and the tone signal supplied from the reproduction circuit 114 and the sound source 122 are synthesized.
[0016]
A DA converter 118 converts the mixing result of the mixer 116 into an analog signal. A sound system 120 amplifies the analog signal and produces a sound. A MIDI interface 124 exchanges MIDI signals with an external MIDI device. Reference numeral 126 denotes another interface that exchanges waveform data and the like with an external device. A timer 128 generates a timer interrupt every predetermined time.
[0017]
A CPU 130 controls each part of the waveform editing system via the bus line 136 based on a program described later. A ROM 132 stores an initial program loader and the like. Reference numeral 134 denotes a RAM which is read and written by the CPU 130.
[0018]
2. Operation of the embodiment
2.1. Recording process of original waveform data
Next, the operation of this embodiment will be described.
First, when the personal computer is turned on, the initial program loader stored in the ROM 132 is executed, and the operating system is started up. When a predetermined operation is performed in this operating system, the waveform editing application program of this embodiment is started. When a predetermined operation is performed in this application program, an automatic performance & waveform recording processing routine shown in FIG. 20 is started.
[0019]
In FIG. 20, when the processing proceeds to step SP202, preparation processing relating to automatic performance and waveform recording is performed. Then, a waveform recording control window 150 shown in FIG. In the waveform recording control window 150, reference numeral 151 denotes an automatic performance file text box, which is provided for designating an automatic performance file name. Reference numeral 152 denotes an automatic performance start button, which is provided to instruct the start of reproduction of a designated automatic performance file. Reference numeral 154 denotes an automatic performance stop button, which is provided for instructing to stop the reproduction of the automatic performance file.
[0020]
A waveform recording start button 156 is provided to instruct the start of waveform recording via the AD converter 108 and the recording circuit 110. Reference numeral 158 denotes a waveform recording stop button, which is provided to instruct to stop the waveform recording. Reference numeral 159 denotes a cancel button, which is provided for instructing to cancel all processes. In the initial state, only the automatic performance file text box 151 among the elements in the waveform recording control window 150 is set to the active (operable) state, and the buttons 152 to 159 are set to the inactive (operation prohibited) state. The
[0021]
Here, when the user inputs an appropriate file name of an automatic performance file (for example, SMF: standard MIDI format file) into the automatic performance file text box 151, the automatic performance start button 152 and the cancel button 159 are set in an active state. , Other elements are set to the inactive state.
[0022]
Next, when the process proceeds to step SP204, an operation event of each element in the active state is detected in the waveform recording control window 150. Next, when the process proceeds to step SP206, the process branches based on the detection result of step SP204. First, when no operation event is detected, the process returns to step SP204, and the detection of the operation event is continued. When the cancel button 159 is clicked with the mouse in the waveform recording control window 150, the processing of this application program is immediately terminated.
[0023]
On the other hand, when automatic performance start button 152 is clicked with the mouse in waveform recording control window 150, the process proceeds to step SP208. Here, the reproduction of the previously specified automatic performance file is started. Furthermore, in step SP208, the automatic performance stop button 154 and the waveform recording start button 156 are set to the active state, and the other elements are set to the inactive state.
[0024]
Next, when the process proceeds to step SP210, an operation event of each element in the active state is detected in the waveform recording control window 150. Next, when the process proceeds to step SP212, the process branches based on the detection result of step SP210. First, when no operation event is detected, the process returns to step SP210, and the detection of the operation event is continued. When the automatic performance stop button 154 is clicked with the mouse, the reproduction processing of the automatic performance file is stopped and the processing of this application program is immediately terminated.
[0025]
On the other hand, when waveform recording start button 156 is clicked with the mouse in waveform recording control window 150, the process proceeds to step SP214. Here, recording of waveform data obtained through the microphone 6, the AD converter 8 and the recording circuit 10 in sequence is started. That is, the waveform data is recorded on the hard disk 112 sequentially through the DA converter 118 and the recording circuit 110. Further, in step SP214, the automatic performance stop button 154 and the waveform recording stop button 158 are set to the active state, and the other elements are set to the inactive state.
[0026]
Here, details of the waveform recording process will be further described with reference to FIG.
FIG. 6A shows a score of automatic performance information, and the timing marked with “↑” is the beat timing. FIG. 4B shows a phrase waveform (original waveform data) to be recorded, which is displayed in accordance with the corresponding timing in FIG. FIG. 3C shows the relationship between waveform data (original waveform data) recorded on the hard disk 112 and automatic performance information.
[0027]
In FIG. 2C, reference numerals 202 and 204 denote automatic performance tracks, which are included in the original automatic performance information (original sequence data). Reference numeral 224 denotes a waveform data track on which recorded original waveform data is recorded. Reference numeral 222 denotes a waveform timing track, in which synchronization control data for synchronizing the automatic performance tracks 202 and 204 and the waveform data track 224 is recorded. Here, the synchronization control data includes data such as recording start timing and synchronization data described later. The waveform timing track 222 and the waveform data track 224 are tracks added to the automatic performance information when the recording process is performed.
[0028]
As is apparent from the processing content up to step SP214, when waveform recording is started, automatic performance has already started. Accordingly, as shown in FIGS. 16A and 16B, the waveform recording start timing is specified by the timing on the performance information of the automatic performance (for example, the number of timing clocks after the automatic performance is started). This identified start timing is recorded in the waveform timing track 222.
[0029]
Thereafter, the waveform recording process and the automatic performance process are continued, but both processes are executed in synchronization with each other. Specifically, the following method is adopted.
(1) The sampling frequency of waveform data is synchronized with the tempo clock for automatic performance. In this case, there is no need to store synchronization data to be described later.
(2) While sampling the waveform data, the synchronization data is recorded on a predetermined track of the automatic performance data (the waveform timing track 222 in the example of FIG. 16).
[0030]
In the above method (2), the following variations can be considered according to the recorded synchronization data. Needless to say, the method of ensuring the synchronization between the automatic performance process and the waveform recording process is not limited to the method described here.
(2-1) For each predetermined number of tempo clocks, record the sample number of the waveform data at that time.
(2-2) Record the sample number of the waveform data at each beat timing (for example, the timing marked with “↑” in FIG. 16A).
(2-3) A sequence position is recorded every predetermined number of samples (for example, every 1000 samples) of the waveform data.
[0031]
Returning to FIG. 20, when the process proceeds to step SP <b> 216 next, an operation event of each element in the active state is detected in the waveform recording control window 150. Next, when the process proceeds to step SP218, the process branches based on the detection result of step SP216. First, when no operation event is detected, the process returns to step SP216, and the detection of the operation event is continued. If the automatic performance stop button 154 is clicked with the mouse, the process proceeds to step SP222, and the reproduction process of the automatic performance file is stopped. On the other hand, if waveform recording stop button 158 is clicked on with a mouse, the process proceeds to step SP220, and the waveform data recording process is stopped.
[0032]
In any case, the process then proceeds to step SP224, where it is determined whether both automatic performance and waveform recording are stopped. Here, if at least one of the processes is continuing, “NO” is determined, the process returns to step SP216, and the detection of the operation event is continued. When both the automatic performance and the waveform recording are stopped, “YES” is determined when the processing proceeds to step SP224 next time, and the processing of this routine ends.
[0033]
Through the above processing, it is understood that the recorded waveform data (original waveform data) is recorded while being associated with the timing of the automatic performance information by the synchronization control data. However, in the processing contents so far, since a series of original waveform data is recorded as it is in the waveform data track 224, it is not possible to cope with an increase or decrease in the tempo of automatic performance. Therefore, since processing such as dividing the original waveform data into a plurality of original sections is necessary, the contents of such processing will be described in detail below.
[0034]
2.2. Waveform data generation processing for playback
2.2.1. Trimming processing (SP2, SP4)
When a predetermined operation is performed after the original waveform data is acquired by the waveform recording process, the program shown in FIG. 4 is started in the waveform editing application program. First, in the original waveform data, there may be a silent section at the start and end. Therefore, when the process proceeds to step SP2, both silent sections are automatically trimmed (deleted).
[0035]
However, when noise is included in the original waveform data, trimming may not always be performed at an appropriate position. Therefore, when the process proceeds to step SP4, the user can arbitrarily correct the automatically determined default trimming position.
[0036]
2.2.2. Parameter setting (SP6)
Next, when the process proceeds to step SP6, various parameters for control point detection are designated by the user. The parameters specified are as follows.
(1) Waveform type: This parameter specifies, for example, the type of waveform data, and is broadly divided into “percussion”, “persistent”, etc., and a plurality of parameters suitable for the original waveform data of various instruments. It is classified as a variation. Based on this waveform type, default values of other parameters described later, such as a threshold value, are determined.
[0037]
By the way, the selection of the “waveform type” is performed as follows. That is, the percussion type selection button 80 and the continuous type selection button 82 as shown in FIG. 19 are displayed on the display 102, and when the user clicks any button with the mouse, the corresponding waveform type is selected. The above-mentioned “percussion type” is not only suitable for use in percussion type waveform data but also preferably applied to intermittent waveform data of other systems. As shown in the figure, since the intermittent waveform is drawn on the percussion type selection button 80 and the continuous waveform is drawn on the continuous type selection button 82, the user can determine the desired waveform type at a glance. can do.
[0038]
(2) Resolution: This parameter is a parameter that specifies the resolution with which the waveform data is searched per bar in order to detect the control points of the strong beat and the weak beat. For example, when “time signature” is “4/4”, “resolution” is “4 minutes”, “4 minutes + 3”, “8 minutes”, “8 minutes + 3”, “16 minutes”, “16 minutes + 3”. "Or" 32 minutes "can be specified (where" +3 "indicates division into triplets). Here, “4 minutes” is the timing to divide one measure into 4 minutes (quarter note timing), “4 minutes + 3” is the timing to 12 minutes, “8 minutes” is the timing to 8 minutes (8th note timing) “8 minutes + 3” is a timing for 24 minutes, “16 minutes” is a timing for 16 minutes, “16 minutes + 3” is a timing for 48 minutes, and “32 minutes” is a timing for 32 minutes. It will be. In setting the resolution, it is necessary to specify the “time signature”, but since this is originally included as a parameter of the automatic performance information, the value of the parameter is used.
[0039]
2.2.3. Unnecessary band elimination filter processing (SP8)
The trimmed waveform data includes various frequency components, but this also includes components (unnecessary bands) that become obstacles for control point detection. Therefore, when the process proceeds to step SP8 next, filter processing is performed to remove these unnecessary bands. This filter processing is roughly divided into two types, band cut processing and high-pass processing. Since the manner in which unnecessary bands are distributed differs depending on the music and musical instrument, the content of the filter processing is the above “waveform type”. It is preferable to determine accordingly. In other words, either or both of the band cut process and the high-pass process are executed according to the waveform type, and the parameters for the filter process are also determined according to the waveform type.
[0040]
Here, an example of setting parameters in the filter processing will be described.
First, a component having a pitch such as a melody in the waveform data is highly likely to become an obstacle when detecting a control point. As a result of analysis of various musical pieces, such components, that is, components of sustained parts such as vocals and bass, often appear in the band of “80 Hz to 8 kHz”, and particularly appear in the band of “100 Hz to 300 Hz”. Therefore, in the band cut process, a filter process is performed in which the band of “80 Hz to 8 kHz” is attenuated, and particularly, the band of “100 Hz to 300 Hz” is strongly attenuated. In addition, since the attack parts (consonant, attack noise, etc.) such as vocals and bass are spread outside the band, the control point can be detected even if filter processing is performed.
[0041]
In band performances, etc., high-frequency sounds such as cymbals are often engraved regularly. In such a case, it is preferable to perform high-pass processing that extracts only this regular high-frequency component. Note that a steep filter characteristic is not required in either the band-cut process or the high-pass process, so it is practically sufficient to use a primary filter in the high-pass process and a secondary filter in the band-cut process. As an example of the result of this unnecessary band removal filter process, FIG. 5A shows the waveform data after trimming, and FIG. 5B shows the waveform of the filter process. In this example of waveform data, the number of bars is “2 bars”, the time is “4/4 time”, and the resolution is “8 minutes”.
[0042]
2.2.4. Default control point determination (SP12)
Next, when the process proceeds to step SP12, a default control point is automatically determined based on the beat timing of the automatic performance information that was reproduced during recording. Since the beat timing is determined by the time signature of the automatic performance information, the beat timing is generated at intervals such as quarter notes or eighth notes. When the tempo changes during the automatic performance, the beat timing changes according to the changed tempo.
[0043]
On the other hand, for the waveform data, the rising start position, peak position, etc. of the volume envelope are detected, and a default control point is set based on the relationship between these detection results and beat timing. The default control point thus determined is displayed on the display 8 together with the waveform data. An example of the display is shown in FIG. In the figure, the waveform data is recorded in stereo, and two systems, left (upper) and right (lower), are shown. The control point is indicated by a vertical broken line on the window in the figure, and is common to both systems. Details of the process for determining the default control point will be described below with reference to FIG.
[0044]
(1) Downsample processing (SP102)
In FIG. 6, when the processing proceeds to step SP102, down-sampling processing is performed on the waveform data from which unnecessary bands are removed. This is because the sampling frequency required to determine the control point is much lower than the sampling frequency of audio data for viewing, so it is preferable to lower the sampling frequency to speed up subsequent processing. That's why.
(2) Absolute value processing (SP104)
Next, when the process proceeds to step SP104, the absolute value of the downsampled waveform data is obtained. An example of the absolute value obtained corresponding to the waveform of FIG. 5B is shown in FIG.
[0045]
(3) Envelope follower processing (SP106)
Next, when the process proceeds to step SP106, an envelope follower process is performed on the absolute value waveform of FIG. This is a process to obtain the envelope waveform of the absolute value waveform. The point is that the envelope waveform rises sharply with respect to the rising edge of the absolute value waveform and gradually falls with respect to the falling edge of the absolute value waveform. There are features. Here, an example in which the algorithm of the envelope follower process is expressed by an equivalent circuit block is shown in FIG. This is a low-pass filter that uses different coefficients when the input rises and falls as a circuit.
[0046]
In FIG. 8, 60 is a delay circuit, which stores the envelope level before one sampling period (period after down-sampling, hereinafter the same). 62 is a subtracter, which subtracts the envelope level one sampling period before from the absolute value waveform level of the current sampling period, and outputs the result as a difference signal d. Reference numerals 66 and 68 denote multipliers. When a difference signal d is supplied to each of them, they are multiplied by coefficients a1 and a2 (where 1> a1> a2> 0) and output.
[0047]
Reference numeral 64 denotes a switch. When the difference signal d is “0” or more, the multiplier 66 is selected. When the difference signal d is less than “0”, the multiplier 68 is selected. The difference signal d is supplied to the multiplier. Reference numeral 70 denotes an adder, which outputs the addition result of the output signals of the selected multipliers 66 and 68 and the envelope level one sampling period before as the envelope level in the current sampling period. A waveform obtained by the envelope follower process is shown in FIG. In order to remove fine fluctuations from this waveform, low-pass filter processing is further performed in step SP106. The result of this low-pass filter process is shown in FIG.
[0048]
(4) Compressor processing (SP108)
In FIG. 6, when the process proceeds to step SP108, the compressor process is executed. That is, the average value of the envelope level based on the result of the envelope follower process is calculated, and the envelope level is corrected so that the level higher than the average value is low and the level lower than the average value is high. The result of such processing is shown in FIG.
[0049]
(5) Edge detection filter processing (SP110)
In FIG. 6, when the process next proceeds to step SP110, an edge detection filter process is executed. This is a process that emphasizes the rise and fall of the envelope level. Here, FIG. 9A shows an example in which the edge detection filter processing algorithm is expressed by an equivalent circuit block (comb filter).
[0050]
In FIG. 9A, reference numeral 72 denotes a delay circuit, which uses an envelope level subjected to compressor processing as an input signal, and outputs the delayed signal by delaying it by n sampling periods (n is a natural number of 2 or more). 74 is a subtracter, which subtracts the input signal before n sampling periods from the input signal of the current sampling period and outputs the result as an edge detection filter processing result. (B) in the figure shows an example of an input signal, (c) in the figure shows an example of a signal that is delayed by n sampling periods and is inverted, and (c) in the figure shows an example of a filter output signal (waveforms in FIGS. Subtraction result). FIG. 10 (a) shows the result of applying such processing to the waveform of FIG. 7 (d).
[0051]
(6) Edge start position / peak position detection processing (SP112)
In FIG. 6, when the process next proceeds to step SP112, an edge start position / peak position detection process is executed. This is processing for detecting the rising edge and peak position of the input signal using the edge detection filter processing result as an input signal. The outline of this process will be described with reference to FIG. FIG. 2A shows a diagram in which a part of the input signal is enlarged on the time axis. In this figure, the input signal is compared with a predetermined threshold Th, and the time when the input signal exceeds the threshold Th is defined as the edge start position (time t1).
[0052]
The output signal level shown in FIG. 5B is set to “0” before time t1, and is set to “−M” (M is a predetermined value) at time t1. Further, at the peak position of the input signal, the output signal is set to the peak value for one sampling period, and then falls to “0” again. The result of performing the processing relating to the waveform of FIG. 10A is shown in FIG.
[0053]
In the signal of FIG. 5B, the timing when the level falls to “−M” is the “edge start position”, and the time during which the level of “−M” continues is the time from the edge start position to the peak position (rising edge). Equal to time Tt). Furthermore, the peak level is equal to the peak level of the edge detection filter processing result ((a) in the figure). Note that the edge start position, the rise time Tt, and the peak level are collectively referred to as “edge information”.
[0054]
(7) Strong beat extraction processing (SP114)
In FIG. 6, when the process next proceeds to step SP114, a strong beat extraction process is executed.
First, as described above, since the original waveform data is recorded in synchronization with the automatic performance tracks 202 and 204 of the automatic performance information, the detection window is determined according to the beat timing of the automatic performance information. This detection window uses the beginning of each section in one measure divided according to the time signature (hereinafter referred to as an estimated strong beat section) as a reference position, and has a width of 1/8 to 1/2 of these estimated strong beat sections. Have. In addition, which value is specifically adopted in the range of 1/8 to 1/2 is determined according to the parameter of “waveform type”.
[0055]
Here, the detection window when the number of bars in the waveform data is “2”, the time signature is “4/4”, and the window width is “1/6” of the estimated strong beat section is shown in FIG. This is shown in FIG. In this figure, the shaded portion is a detection window, and a portion of “1/3” (1/18 of the estimated strong beat section width) of each detection window is “2 / 3 ”(2/18 of the estimated strong beat section width) is set to be located after the reference position.
[0056]
Next, among the edge information to which the peak position belongs to each detection window, information whose peak level exceeds a predetermined threshold Th1 is extracted. However, when a plurality of edge information exists in one detection window, only edge information having the maximum peak level is extracted. The result of performing such extraction on the waveform of FIG. 10C is shown in FIG. In FIG. 4C, the first (leftmost) detection window has two edge information peak positions exceeding the threshold Th1, but referring to FIG. 4D, an edge with a higher peak level is shown. Only information is extracted. Also, edge information exists in the sixth detection window from the left end in the figure (c), but since the peak level does not exceed the threshold value Th1, it is not extracted in the figure (d).
[0057]
(8) Weak beat extraction processing (SP116)
In FIG. 6, when the process proceeds to step SP116 next, a weak beat extraction process is executed.
In this process, the reference position of the detection window is set at a position where each bar is divided based on the “resolution” parameter specified in the parameter setting process (SP6) described above. However, the reference position corresponding to the detection window in which a strong beat has already been detected in the previous step SP114 is excluded in this step.
[0058]
Therefore, if a strong beat is detected in each detection window in step SP114, for example, a new detection window having a beat timing of 8 minutes between the beat timings of 4 minutes of the automatic performance information as reference positions is provided. Will be provided. On the other hand, for the detection window from which the strong beat was not previously extracted (sixth detection window from the left end in FIG. 10C), the detection window for extracting the weak beat is again at the same position, that is, in this step. The beat timing position is set to 4 minutes. As a result, the detection window for weak beat extraction is set as shown in the shaded portion in FIG.
[0059]
Also in this process, “1/3” (1/18 of the estimated strong beat section width) of each detection window is set to “2/3” (2/18 of the estimated strong beat section width) before the reference position. ) Is set to be positioned after the reference position. Next, the edge information to which the peak position belongs to each detection window is extracted that exceeds a predetermined threshold Th2. However, when a plurality of edge information exists in one detection window, only edge information having the maximum peak level is extracted.
[0060]
Here, the threshold value Th2 is set to a level of about “1/5” of the threshold value Th1, and the threshold value Th is set to a value smaller than the threshold value Th2. The extraction result of the strong beat and the weak beat extracted by the processing so far is shown in FIG. According to FIG. 5B, the edge information that is not extracted because the peak level is insufficient in the previous strong beat extraction process (SP114) is also extracted by the current extraction process. Of the edge information extracted in steps SP114 and SP116, the edge start position is nothing but the control point described in FIG.
[0061]
(9) Control point forced setting process (SP118)
Next, when the process proceeds to step SP118, if necessary, the control point is forcibly set to the reference position of the detection window where no edge information has been detected so far. “When necessary” specifically refers to the case where “sustained” is specified as the waveform type. The reason for this setting is that the envelope of the “sustained system” waveform is not regularly attenuated (simple attenuation), so the control point is forcibly set even at a position where no rise is detected. This is because the time axis control that is musically appropriate can be performed by setting.
[0062]
2.2.5. Control point editing process (SP14)
Next, when the process proceeds to step SP14, the default control point is edited by the user. Specifically, control points are added, deleted, or moved as necessary on the window.
[0063]
2.2.6. Determination of flattened waveform data for insertion sections 1i-12i
As described above, the section delimited by the start point, end point, and control point of the waveform data is referred to as “original section” in this specification. If the control point is determined as shown in FIG. 2 (a), the waveform data is divided into 12 original sections 1r-12r as shown in the upper rectangular row of FIG. 2 (b). become.
[0064]
Next, as shown in the lower rectangular column in FIG. 5B, 12 sections (insertion sections 1i to 12i) having the same length as each original section are created. The waveform data following the original sections 1r to 12r is stored in 12i. As a result, the original sections 1r to 12r and the corresponding insertion sections 1i to 12i are joined to obtain joined sections 1t to 12t as shown in FIG. Therefore, details of such processing will be described below.
[0065]
Returning to FIG. 4, when the process proceeds to step SP <b> 16, the waveform data (before the envelope adjustment) set in the insertion sections 1 i to 12 i by the user
(1) As shown in FIG. 13 (a), the next waveform data (n + 1) r of the corresponding original section nr (where n = 1 to 12) is directly copied, or
(2) Waveform data obtained by inverting the waveform data of the corresponding original section nr on the time axis as shown in FIG.
Is selected.
Here, in the default state, when the waveform type is “persistent”, the waveform data of FIG. 11A is selected, and when the waveform type is the percussion system, the waveform data of FIG. The reason will be explained.
[0066]
<For continuous sound>
First, in a continuous sound, since the original section nr and the insertion section ni = (n + 1) r are originally continuous sections, a smooth connection from the original section nr to the insertion section (n + 1) r is guaranteed. Yes. Here, it is possible to use a section other than the insertion section (n + 1) r as the insertion section, but the control point is set in a portion where there is no attack (in the middle of the continuous waveform) in the continuous sound. (Refer to step SP118), so consideration is required. That is, in this case, if the phase of the original section nr and the insertion section are not matched, annoying noise is generated, so that it is necessary to perform phase matching between them, and the processing becomes complicated. On the other hand, if the section (n + 1) r next to the original section nr is used as the insertion section as in the example described above, the waveform data of the insertion section can be created based on more stable waveform data.
[0067]
In addition, in the case of a continuous sound, let us assume a case where there is an attack of the next sound immediately after the control point. In this case, generally, the pitch of the next sound is different from the pitch of the previous sound. Although it is not originally desirable that the pitch of the original section and that of the insertion section be different, the experimental results show that even if the pitch of the two is different, it is not very noticeable. This is considered to be due to the fact that the envelope level of the inserted section is controlled so as to continue to attenuate smoothly from the previous original section. In other words, it stands out when the timbre or pitch changes in the attack part of the newly started sound, but when the timbre or pitch changes in the middle of the decaying waveform, it is relatively conspicuous because the impression of the previous attack part is strong. It seems that there is no
[0068]
<For percussion sounds>
Next, since percussion-type sounds originally have many noise components, noticeable noise often does not occur at the connection from the original section nr to the insertion section ni. However, if the original section nr or the next original section (n + 1) r or the like is used as it is as the insertion section ni, the attack noise at the beginning of the waveform may be somewhat disturbing. Therefore, by using the waveform data obtained by inverting the waveform data of the original section nr on the time axis as the insertion section ni, such a problem can be solved. Furthermore, if the connection portion between the original section nr and the insertion section ni is cross-fade, it becomes possible to connect the two more smoothly. When the inverted waveform data is read to the end, attack noise is reproduced at the end portion of the inverted waveform data, which may be a little annoying. In such a case, the inverted waveform data may be read back (inverted further on the time axis) at a point in the middle of the inverted waveform data (for example, a point having a length of about 2/3 from the beginning).
[0069]
The insertion section is not limited to the default one described above, and since the user can specify the generation manner of a desired insertion section for each original section, it is preferable to select the most preferable one in terms of audibility. In step SP16, when the waveform data of the insertion section is selected, the level of each part of the waveform data is divided by the envelope level of the waveform data. Thereby, the waveform data of the insertion section is converted into waveform data having a flat envelope.
[0070]
2.2.7. Envelope for insert sections 1i-12i
Next, when the process proceeds to step SP18, the envelope waveforms of the insertion sections 1i to 12i are determined. The determination method will be described with reference to FIG. In the figure, the maximum value of the envelope level of an original section nr is L1, the envelope level at the end of the original section nr is L2, and the time from when this maximum value L1 appears until the end of the original section nr is T. Within this period, the attenuation rate dr of the envelope level is
dr = (L1 / L2)^{1 / T}
Can be obtained.
[0071]
Next, the initial value of the envelope level of the insertion section ni corresponding to the original section nr is set to L2, and the envelope of the insertion section ni is determined so that the attenuation rate dr is maintained. Specifically, when the start time t = 0 of the insertion section ni, the envelope level of each part in the insertion section ni is L2 / dr.^tSought by. Thereby, as shown in FIG. 14, the envelope characteristic of the insertion section ni is set so as to be naturally connected to the original section nr.
[0072]
However, when the simple determination mode is selected at the time of determining the control point, the envelope level may be maximized at the end of the original section nr. In such a case, as shown in FIG. 15, the envelope level of the insertion section ni is limited to the level at the end of the original section nr. Specifically, when the attenuation rate dr determined by the above formula is smaller than 1, the attenuation rate dr for determining the envelope value of the insertion section is forcibly set to 1, or 1 regarding the attenuation rate dr. A larger lower limit value “dr_min” may be determined, and the attenuation rate dr may be controlled to be always larger than that.
[0073]
As described above, when the envelope of each insertion section is determined, each portion of the flattened waveform data of each insertion section 1i to 12i is multiplied by the determined envelope. Thereby, the waveform data of each insertion section has this determined envelope.
[0074]
As described above, when the waveform data of the insertion sections 1i to 12i is determined, the waveform data of the combined sections 1t to 12t is determined. The waveform data of these combined sections 1t to 12t is written in the waveform data track 224 of automatic performance information instead of the original waveform data. Further, in the waveform timing track 222, the start timing (number of timing clocks) of each of the combined sections 1t to 12t and the rise time Tt of the waveform data of these combined sections are written. The rise time Tt is not essential, but by writing this, it becomes possible to reproduce the waveform data at a more preferable timing (refer to a reproduction tempo setting / change process described later).
[0075]
2.3. Playback tempo setting / change processing
The user can set / change the playback tempo appropriately before the performance processing or during the performance processing. Here, if the set tempo is equal to the tempo at the time of recording, the number of clocks recorded in the waveform timing track 222 (see FIG. 16) may be used as it is. However, if the playback tempo is different from the recording tempo, simply controlling the playback start timing of each section according to the ratio between the two causes a problem that “leaning” occurs particularly in a waveform with a slow rise. .
[0076]
The contents will be described with reference to FIG. In FIG. 6A, the time from the reproduction start time (0) until the start of the waveform rise is the edge start time Ts, and after the start of the rise, the time until the waveform level reaches the peak is the rise time. Tt.
[0077]
The solid line in FIG. 5A shows the envelope level of the waveform data reproduced at the tempo at the time of recording. In human hearing, it is felt that a beat is generated at the peak position of the envelope level, that is, at the timing when the time “Ts + Tt” has elapsed after the start of reproduction. Next, an alternate long and short dash line in FIG. 5A shows an example in which waveform data is reproduced by extending the tempo at the time of recording by n times. In the illustrated example, the drawing is performed on the assumption that “n = 2”. In this case, the edge start time is n times “nTs” at the time of recording, but the time when the user actually feels a beat is “nTs + Tt”, which is n times shorter than the time of recording “n (Ts + Tt)”. .
[0078]
As a result, when the waveform is expanded and reproduced, it is felt that a beat is generated at a timing faster than the preferred timing. On the other hand, when the tempo is compressed more than at the time of recording, it is felt that a beat is generated at a timing later than the preferred timing.
[0079]
Therefore, in this embodiment, when the playback tempo is set or changed, the number of generation start clocks recorded in the waveform timing track 222 is the time corresponding to the number of clocks (clock number × clock cycle). The value is corrected to be “n (Ts + Tt) −Tt” (or closest). As a result, as shown in FIG. 3B, the audible beat, that is, the peak position, becomes the timing when the rising time Tt has further passed, that is, “n (Ts + Tt)”. Instead of changing the number of generation start clocks according to the tempo, the clock cycle may be increased or decreased according to the rise time Tt. That is, each time a tempo clock is generated, the period until the next tempo clock is appropriately increased or decreased, whereby the timing control according to the tempo can be performed while keeping the number of generation start clocks constant.
[0080]
2.4. Performance processing
Next, an operation for performing automatic performance processing based on automatic performance information (synthetic sequence data) formed by adding the waveform timing track 222 and the waveform data track 224 described above will be described. First, when the start of automatic performance is instructed, a tempo clock is generated at intervals of “1/64” of quarter notes based on the designated tempo. During automatic performance, the program shown in FIG. 17 is executed every time a tempo clock is generated.
[0081]
In FIG. 17, when the process proceeds to step SP32, the variable tcount is incremented by “1”. The variable tcount is initially set to “0” at the start of automatic performance, and is a variable for counting the number of tempo clocks from the start of automatic performance to the present. Next, when the process proceeds to step SP34, it is determined whether or not an event timing other than the waveform data has been reached based on the value of the variable tcount.
[0082]
That is, in the automatic performance tracks 202 and 204, event data such as note-on and note-off is recorded in the order of occurrence, and in these event data, timing data corresponding to the tempo clock that should generate the event is recorded. include. Accordingly, it is possible to determine whether or not the event timing has been reached by referring to the timing data in the event data at the head of each track.
[0083]
If "YES" is determined in the step SP34, the process proceeds to a step SP36, and an event process corresponding to the event data is executed. For example, if the event data is a note-on event, a new tone generation channel is assigned in the sound source 122 based on a command from the CPU 130, and a tone signal is synthesized in the tone generation channel. The synthesized musical sound signal is generated through the mixer 116, the DA converter 118, and the sound system 120 in order. If the event data is a note-off event, the mute process is performed in the corresponding sound generation channel.
[0084]
On the other hand, if the event timing of the next event data has not yet been reached, “NO” is determined in step SP34, and the process proceeds to step SP38. Here, it is determined whether or not the waveform data read start timing of any of the combined sections has been reached. As described above, the default read start timing is recorded in the waveform timing track 222 for the waveform data in the combined section. However, the read start timing here is a timing after correction based on the rise time Tt, that is, a timing corresponding to the above-described “n (Ts + Tt) −Tt”.
[0085]
If "YES" is determined here, the process proceeds to step SP40, and reading of the corresponding waveform data is started. Here, the reading speed is controlled according to the value of the pitch shift amount described later. When the pitch shift amount is “0”, the reading speed is the same as the writing speed at the time of recording. When the pitch shift amount is positive, it is faster. When the pitch shift amount is negative, it is slower. With speed. As is well known, the pitch of the read waveform data increases as the reading speed increases, and decreases as the reading speed decreases.
[0086]
Even if another waveform data reading process is performed immediately before this point in time when the reading of the corresponding waveform data is started, in step SP40, the new waveform data is replaced with the new waveform data. Reading of the waveform data is started. On the other hand, if “NO” is determined in step SP38, step SP40 is skipped, and the processing of this routine ends without changing the waveform data being read.
[0087]
According to the above processing, when the variable tcount reaches the read start timing of the first combined section 1t, waveform reading of the combined section 1t is started immediately. Thereafter, when the variable tcount reaches the reading start timing of the next combined section 2t, the reading of the waveform data of the combined section 1t is stopped and the reading of the waveform data of the combined section 2t is started. In order to smoothly connect the coupling section 1t and the coupling section 2t, the waveform data of the portion where reading of the coupling section 1t is stopped and the waveform data of the portion where reading of the coupling section 2t is started may be cross-fade connected. Good. Through the above processing, the waveform data that is sequentially read out is sounded through the reproduction circuit 114, the mixer 116, the DA converter 118, and the sound system 120 in sequence.
[0088]
Similarly, reading from the combined section 3t is sequentially started in accordance with the increase of the variable tcount. Next, a musical sound waveform actually generated by such processing will be described with reference to FIG. FIG. 5B shows a section that is read when the tempo ratio during playback and recording is set to 1.00. In such a case, reading of the next combined section is started when “1/2” of each combined section, that is, all of the original section is read. As a result, the reproduced sound waveform matches the original waveform data.
[0089]
FIG. 5A shows a section that is read when the tempo ratio during reproduction and recording is set to 0.67. In such a case, reading of the next section is started when about “67%” is reproduced based on the length of the original section. As described above, the timing at which the reading of the next section is actually started differs depending on the rising time Tt of the next section. This prevents the rest of each original section (about 33%) and the inserted section from being played.
[0090]
FIG. 4C shows a section that is read when the tempo ratio during reproduction and recording is set to 1.65. In such a case, reading of the next section is started when about “165%” is reproduced based on the length of the original section. As a result, each original section and the first 65% of each inserted section are reproduced.
[0091]
The user can change the tempo at the time of reproduction and the waveform data used for reproduction in real time via the operation element 104. Similarly, the speed at which each section is read, that is, the pitch shift amount, can be changed in real time via the operation element 104. Further, the waveform data to be reproduced, the tempo, or the pitch shift amount may be automatically changed based on a predetermined sequence. Thereby, the waveform data is reproduced and sounded in various manners based on the user's operation or a predetermined sequence.
[0092]
3. Effects of the embodiment
As described above, according to the present embodiment, when the original waveform data is recorded on the waveform data track 224, the synchronization data for the automatic performance information is recorded on the waveform timing track 222. The waveform data for reproduction generated based on this can be automatically synchronized with the original automatic performance information.
[0093]
Furthermore, in the present embodiment, “n” is generated by correcting the number of generation start clocks according to the relationship between the original edge start time Ts and rise time Tt and the tempo at the time of reproduction (tempo expansion / contraction ratio n). Since the reproduction of each original section can be started at the timing of (Ts + Tt) −Tt ”, consistency between the tempo expansion / contraction ratio n and the audible beat timing can be ensured.
[0094]
4). Modified example
The present invention is not limited to the above-described embodiment, and various modifications can be made as follows, for example.
(1) In the above embodiment, the waveform editing system is realized by an application program that runs on a personal computer, but the same function is used for various electronic musical instruments, mobile phones, amusement devices, and other devices that generate musical sounds. Also good. Further, the software used in the above embodiment can be stored in a recording medium such as a CD-ROM or a floppy disk and distributed, or can be distributed through a transmission path.
[0095]
(2) In the above embodiment, the envelope of the entire waveform data is analyzed. However, the envelope may be analyzed only in a portion near the reference position, for example, a portion corresponding to each detection window.
[0096]
(3) In the above embodiment, the waveform data of the insertion section is generated in advance corresponding to each original section. However, the waveform data of each insertion section is reproduced during the waveform data reproduction or in response to an instruction for waveform reproduction. You may make it produce | generate immediately before starting reproduction | regeneration. Thereby, the storage capacity for storing waveform data can be reduced.
[0097]
(4) It goes without saying that the process of determining the division position (control point) for the original waveform data is not limited to that of the above embodiment. For example, in the above embodiment, the control point is determined using the beat timing of the automatic performance information as the reference position of the detection window. However, instead of the beat timing, each note-on timing of the automatic performance information (each of FIG. 16A). Note timing (note timing) or note-off timing may be used as the reference position of the detection window.
[0098]
(5) In the above embodiment, the process of determining the control point is performed after the original waveform data is once recorded in the waveform data track 224. However, if the processing capability of the CPU 130 is sufficiently high, the original waveform data The control point may be determined simultaneously with recording.
[0099]
(6) In the above embodiment, the resolution for determining the control point is specified after recording the original waveform data. However, the resolution may be specified before recording the original waveform data or after recording.
[0100]
(7) In the unnecessary band removal process in step SP8 of the above embodiment, the filter process by the high-pass process and the band cut process is performed, but instead of or in addition to these, other processes such as attenuating the low band are performed. You may perform the process to boost, the process which boosts a high region, etc.
[0101]
(8) In step SP110 of the above embodiment, the filtering process using the comb filter is performed to detect the edge portion. Instead, any filtering process that generates a value corresponding to the slope of the envelope is used. Edge detection may be performed. For example, filter processing that simply differentiates the envelope level may be performed, and low-pass filter processing may be performed on the differentiation result.
[0102]
(9) In step SP116 of the above embodiment, the reference position of the detection window for weak beat detection bisects each estimated strong beat section, that is, the reference position for strong beat detection. Provided in position. However, the position of the detection window for weak beat detection is not limited to this. That is, a position that bisects the interval between the edge start positions or the peak positions of strong beats actually extracted in step SP114 is obtained, and this obtained position is set as a reference position of a detection window for weak beat detection. Good.
[0103]
(10) In step SP16 of the above embodiment, the waveform data of the corresponding original section or the inverted version thereof is used as it is as the waveform data of the insertion section before the envelope adjustment. However, in the case of waveform data such as a melody part that has a particularly stable pitch component, the pitch of the latter half of the original section is detected and a part (partial waveform) of the original section is repeated in this pitch unit. An insert section may be generated. Thereby, it is possible to prevent instability peculiar to the attack portion from appearing in the insertion section.
[0104]
Note that the size of the partial waveform may be constant (loop waveform) or may be set to a random length. Also, if the pitch is detected stably in the latter half of the original section, a part of the original section is repeated, and if the pitch is not detected, the entire original section (or the inverted version) is copied. The waveform data before the envelope adjustment of the insertion section may be set.
[0105]
(11) In the above embodiment, each insertion section is created based on the waveform data of the original section immediately before (or an inverted version thereof), but based on the waveform data of the next original section. Each insert section may be generated. For example, the insertion section 1i may be generated based on the waveform data of the original section 2r.
[0106]
(12) In the above embodiment, the type of waveform data is divided into two types, “percussion type” and “persistent type”, but the waveform data may be divided into three or more types.
[0107]
(13) In the above embodiment, the detection window for extracting strong beats is set according to the setting of the time signature, and the detection window for extracting weak beats is set according to the setting of the resolution. It is not necessary to set according to the resolution. For example, a detection window for extracting strong beats and a detection window for extracting weak beats may be designated independently. Alternatively, a detection window for extracting strong beats and a detection window for extracting weak beats may be set in accordance with the set time signature. There is also a method of setting both detection windows based on the timing of the metronome during recording as described above.
[0108]
【The invention's effect】
As described above, according to the present invention, waveform data can be easily synchronized with automatic performance information in order to record waveform data while recording synchronous data indicating the timing relationship between automatic performance information and waveform data. Can do.
Furthermore, according to the configuration in which the envelope level of the waveform data is obtained and the waveform data break position is obtained based on the synchronization data and the envelope level, the effective rising position can be efficiently extracted as the break position. Further, by extracting the rising position corresponding to the estimated beat position, erroneous detection can be prevented and the rising position can be detected stably. In other words, it is possible to set a position that is more musically appropriate in the vicinity of the position that is originally expected to be divided, and the division position is erroneously detected or divided at a position that is not musically appropriate. Such a situation can be prevented in advance.
[0109]
Furthermore, according to the configuration in which the estimated beat position is determined based on the beat timing, note-on timing, or note-off timing of the automatic performance information, the break position is determined while efficiently using the information originally included in the automatic performance information. Can be detected.
Furthermore, according to the configuration of selecting one rising position among a plurality of rising positions belonging to one predetermined range based on the beat timing, the note-on timing, or the note-off timing, and extracting it as a waveform data separation position, Unnecessary rising positions can be efficiently removed.
[Brief description of the drawings]
FIG. 1 is a block diagram of a waveform editing system according to an embodiment of the present invention.
FIG. 2 is an operation explanatory diagram of processing for generating an insertion section and a combined section in the embodiment.
FIG. 3 is an operation explanatory diagram of a reproduction process in the conventional example and the embodiment.
FIG. 4 is a flowchart of reproduction waveform data generation processing in the embodiment.
FIG. 5 is a waveform diagram before and after unnecessary band elimination processing (SP8) in the embodiment.
FIG. 6 is a flowchart of a default control point determination process.
FIG. 7 is an output waveform diagram of absolute value conversion processing (SP104).
FIG. 8 is an equivalent circuit diagram of envelope follower processing (SP106).
FIG. 9 is an equivalent circuit diagram of edge detection filter processing and a waveform diagram of each part thereof.
FIG. 10 is an output waveform diagram of edge detection filter processing, edge start position / peak position detection processing, and strong beat extraction processing (SP110 to SP114).
FIG. 11 is an operation explanatory diagram of edge start position / peak position detection processing (SP112).
FIG. 12 is an operation explanatory diagram and an output waveform diagram of weak beat extraction processing (SP116).
FIG. 13 is an operation explanatory diagram of waveform data setting processing in an insertion section ni.
FIG. 14 is an operation explanatory diagram of an envelope level setting process in the insertion section ni.
FIG. 15 is an operation explanatory diagram of an envelope level setting process in the insertion section ni.
FIG. 16 is a diagram showing a timing relationship between automatic performance information and original waveform data.
FIG. 17 is a flowchart of a performance processing routine.
FIG. 18 is an explanatory diagram of compression / decompression processing of waveform data to be reproduced.
19 is a diagram showing a percussion type selection button 80 and a continuous type selection button 82. FIG.
FIG. 20 is a flowchart of an automatic performance & waveform recording processing routine.
21 is a diagram showing a display example of a waveform recording control window 150. FIG.
[Explanation of symbols]
1i to 12i... Insertion section, 1r to 12r... Original section, 1t to 12t... Combined section, 60... Delay circuit, 62 ... Subtractor, 64 ... Switch, 66, 68. ... adder, 72 ... delay circuit, 74 ... subtractor, 80 ... percussion selection button, 82 ... continuous selection button, 102 ... indicator, 104 ... operator, 106 ... microphone, 108 ... AD converter, 110 ... recording circuit, 112 ... hard disk, 114 ... playback circuit, 116 ... mixer, 118 ... DA converter, 120 ... sound system, 122 ... sound source, 124 ... MIDI interface , 126 ... interface, 128 ... timer, 130 ... CPU, 132 ... ROM, 134 ... RAM, 1 0 ... Waveform recording control window, 151 ... Automatic performance file text box, 152 ... Automatic performance start button, 154 ... Automatic performance stop button, 156 ... Waveform recording start button, 158 ... Waveform recording stop button, 159 ... Cancel button, 202, 204 ... Automatic performance track, 222 ... Waveform timing track, 224 ... Waveform data track.

Claims (14)

The process of starting playback of automatic performance information,
The process of starting recording waveform data;
Recording the waveform data while recording synchronization control data indicating a timing relationship between the automatic performance information and the waveform data;
Obtaining an envelope level of the waveform data;
A waveform data analysis method comprising: a delimiter position detection step of obtaining a delimiter position of the waveform data based on the automatic performance information, the synchronization control data, and the envelope level. The separation position detection process includes:
Based on the automatic performance information and the synchronization control data, an estimation process for determining an estimated break position of the waveform data;
A detection process of detecting one or more rising positions of the waveform data within a predetermined range corresponding to the estimated break position;
Waveform data analyzing method according to claim 1, wherein the and an extraction process of extracting one of said detected one or a plurality of rising position as a sectioning position. The predetermined range is composed of first and second predetermined ranges;
In the extraction process, for the rising positions belonging to the first predetermined range, the rising positions are extracted as the separation positions on condition that level values corresponding to the rising positions exceed a predetermined first threshold value. In addition, for the rising positions belonging to the second predetermined range, the rising position is determined as the separation position on the condition that the level value corresponding to each of the rising positions exceeds a second threshold value lower than the first threshold value. To be extracted as a process
The waveform data analysis method according to claim 2. 3. The waveform data analysis method according to claim 2 , wherein the estimation step determines an estimated break position of the waveform data based on a beat timing, a note-on timing, or a note-off timing of the automatic performance information. 3. The waveform data analysis method according to claim 2 , wherein, in the extraction process, any rising position is extracted as the separation position based on the detected intensity of the rising position. The process of starting playback of automatic performance information,
The process of starting recording waveform data;
Recording the waveform data while recording synchronization control data indicating a timing relationship between the automatic performance information and the waveform data;
Determining an estimated beat position based on the beat timing of the automatic performance information and the synchronization control data;
Waveform data analysis method characterized in that it comprises a partitioning position determining process of determining the break position of the waveform data based on the estimated beat position. The process of starting playback of automatic performance information,
The process of starting recording waveform data;
Recording the waveform data while recording synchronization control data indicating a timing relationship between the automatic performance information and the waveform data;
Determining an estimated rising position based on the note-on timing of the automatic performance information and the synchronization control data;
Waveform data analysis method characterized in that it comprises a partitioning position determining process of determining the break position of the waveform data based on the estimated rise position. The process of starting playback of automatic performance information,
The process of starting recording waveform data;
Recording the waveform data while recording synchronization control data indicating a timing relationship between the automatic performance information and the waveform data;
Determining an estimated break position based on the automatic performance information and the synchronization control data;
An analysis process for analyzing a portion in the vicinity of the estimated break position in the waveform data;
Waveform data analysis method characterized in that it comprises a partitioning position determining process of obtaining the waveform data across the break position based on the analysis result.   9. The waveform data analysis method according to claim 8, wherein the analysis step is a step of detecting a rising position by analyzing an envelope of the waveform data.   9. The waveform data analysis method according to claim 8, wherein in the delimiter position determination step, one delimiter position is determined for each estimated delimiter position based on a plurality of rising positions included in the analysis result. The sampling period of the tempo clock and the waveform data of automatic performance for reproducing the automatic performance information is synchronized,
The waveform data analysis method according to claim 1, wherein the synchronization control data includes timing data indicating a recording start timing of the waveform data. The synchronization control data includes timing data indicating a recording start timing of the waveform data, synchronization data for synchronizing a tempo clock of the automatic performance and a sampling period of the waveform data. Thru | or 10 waveform data analysis method in any one of.   13. A waveform data analysis apparatus, wherein the waveform data analysis method according to claim 1 is executed. A computer-readable recording medium storing a program for causing a computer to execute the waveform data analysis method according to claim 1.

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