JP3457582B2 - Automatic expression device for music - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for automatically adding musical expressions to music, and more particularly to a device for playing music using the MIDI standard, which is used for adding music with facial expression information that gives a human-like performance. A device with an automatic facial expression.

[0002]

2. Description of the Related Art There are roughly two types of means for distributing music data via a network. One of them is a method of digitizing (sampling) sound waveform data and transmitting performance information as it is. However, this method has a drawback in that a large amount of data is transmitted and inevitably the transmission time becomes long when passing through a network.

The other is a method of converting into some standard represented by the MIDI standard and distributing it. The method of converting data based on such a standard has an advantage that the amount of data is small, but has a problem that much information is deleted. In particular, in the case of the MIDI standard, the data amount is 1 to 10% of the data amount compared with the sampling data, and therefore it is adopted in communication karaoke and the like. In the case of describing performance data in the MIDI standard, if the performance data described in the MIDI standard according to the musical score is reproduced by a sound source compatible with the MIDI standard, the performance is faithful to the musical score, but it is largely different from human performance. Sounds different. Therefore, in order to perform with a human touch, the work of adding expressions is required, but this work requires a great deal of labor and specialized knowledge of the playing technique of multiple musical instruments, and is performed manually. There must be.

The MIDI standard is a standard for connecting electronic musical instruments to each other or connecting an electronic tone generator to a computer for performance.

On the other hand, some automatic facial expression systems have been considered so far, but in the conventional system, the processing is limited to each part (musical instrument) such as only piano or guitar. , Part-by-part processing that does not consider the expression of the whole song is performed.

[0006]

As described above, there are at least the following two problems in the conventional expression of songs.

Since the MIDI standard has a small amount of information,
It is convenient for data distribution via music networks such as online karaoke and recording media such as floppy disks and compact disks, but in order to make it sound like an actual performance, data conversion is mainly done manually, Requires a great deal of effort and extensive expertise.

In the system for automatically adding facial expressions, only the processing for each part is performed, and the facial expressions are not balanced for the entire song.

Therefore, a main object of the present invention is to provide an automatic musical expression adding device for music which can automatically add the expression that a human being has done to the entire music.

[0010]

The present invention is based on the MIDI standard.
Automatic facial expression device for musical expressions to express the musical composition described in
So, the composition of the rhythm instrument and the sense of rhythm of the rhythm instrument
Rhythm instrument pattern that holds the rhythm instrument pattern shown
Holding means and one or more in conformity with the MIDI standard
A specific instrument from MIDI data consisting of instrument parts
Rhythm that generates the first rhythm pattern from the part
Input the means of composition and the second rhythm pattern that the user likes.
Pattern inputting means for playing, and the rhythm musical instrument
The rhythm musical instrument pattern held by the pattern holding means.
Turn and the first re-drive generated from the rhythm generating means.
Input from the rhythm pattern and the rhythm pattern input means.
The performance pattern is based on the applied second rhythm pattern.
Performance pattern generation means for generating
Preserve the facial expression pattern of one or more outside instruments
The facial expression pattern holding means and the facial expression pattern
Based on the facial expression pattern held by the holding means,
Part of one or more musical instruments of the MIDI data
Therefore, the expression putting means for giving an expression, and the performance pattern
The pronunciation pattern of the performance pattern generated by the
To the MIDI data with the expression.
Timing adjusting means for adjusting the iming and the performance
A performance pattern generated by the pattern generation means,
The timing-matched MID with the expression
Generate new MIDI data based on the I data
And output means for outputting.

Preferably, the performance pattern generating means
Is the first rhythm pattern and the second rhythm pattern.
Select one of the turns, and select the first rhythm pattern
And extract the common rhythm of the second rhythm pattern,
Similar to the selected rhythm pattern from the common rhythm
Generated rhythm pattern,
Based on this, a performance pattern is generated.

The present invention is also described in the MIDI standard.
A device for automatically adding a facial expression to a musical composition,
Rhythm instrument structure and rhythm showing the sense of rhythm of rhythm instrument
Rhythm musical instrument pattern holding means for holding musical instrument patterns
And one or more instruments that comply with the MIDI standard.
Part of a specific instrument in MIDI data consisting of
Rhythm generating means for generating a rhythm pattern from
Rhythm musical instrument pattern holding means
Rhythm instrument pattern and generated by the rhythm generation means
Generated playing pattern based on
Playing pattern generating means and the user's
Dynamics, pronunciation timing fluctuations, and ghost sounds
Enter facial expression pattern preference
Input means and the expression pattern input means.
Based on the preference of the expression pattern of the rhythm instrument
With facial expression to give the desired expression to the playing pattern
The adding means and one or more musical instruments other than the rhythm musical instrument.
Facial expression pattern holding means for holding the facial expression pattern
And a table held by the expression pattern holding means.
Based on the emotional pattern, among the MIDI data
Facial expression to be applied to one or more musical instrument parts
The expression is added by the attaching means and the expression adding means.
The expression is added to the pronunciation timing of the
Timing to match the pronunciation timing of the MIDI data
Facial expression by means of matching
The timing is matched with the attached performance pattern.
Based on the MIDI data with the expression,
And an output means for generating and outputting the MIDI data.
Get

The present invention is also described in the MIDI standard.
A device for automatically adding a facial expression to a musical composition,
Rhythm instrument structure and rhythm showing the sense of rhythm of rhythm instrument
Rhythm musical instrument pattern holding means for holding musical instrument patterns
And one or more instruments that comply with the MIDI standard.
Part of a specific instrument in MIDI data consisting of
Rhythm generating means for generating a rhythm pattern from
Liz held by the rhythm instrument pattern holding means
Generated by the rhythm generation means
Generate a playing pattern based on the rhythm pattern
Performance pattern generation means and one or more
Expression putter that holds the expression pattern of a number of musical instruments
Holding means and the expression holding pattern holding means.
Based on the facial expression pattern, the MIDI device
At least the facial expression pattern holding means
Other than rhythm instruments that hold facial expression patterns
Because it is an instrument and the part of the instrument that leads the performance,
Expression expression means and music that leads the performance
Timing that holds the pronunciation timing of the instrument in phrase units
Holding means, the MIDI data with the expression, and
And phrase recognition for recognizing phrases in the performance pattern
Means and the pronunciation held by the timing holding means
At the timing, the MIDI data with the expression and the
And the timing of pronunciation of the performance pattern in phrase units
Timing adjusting means and the timing adjusting means
The said MIDI data with the expression and the front
New MIDI data based on the playing pattern
An output means for generating and outputting the phrase recognition
Means, a pronunciation interval P _i of note _i, the period with the sound of the note i
The distance is D _i, and A _i = P _i / P _i−1 and B _i = P _i −D _i .
When any of the following conditions (i) to (iv) is met,
When satisfied, note i is recognized as the beginning of the phrase. (I) A _i <0.5 and B _i-1 ≧ eighth note length
Is _{(ii) B i-1 ≧} 4 note minutes long (iii) A _i ≦ 0.15 and, D _i-1 ≧ note 2 minutes
Length (iv) A _i <0.2 and B _i-1 > 0

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

FIG. 1 is a block diagram showing a peripheral portion of an automatic facial expression adding device according to the present invention. MIDI data is input to an input terminal of the automatic facial expression adding device according to the present invention, and output from the output terminal. Automatically outputs MIDI data with facial expressions. Further, in this automatic facial expression adding device, a user (user) designates which rhythm of a large number of musical instruments existing in the MIDI data input to the input terminal, and a user. Rhythm pattern input means B, which allows the user to input his or her favorite rhythm pattern, and fill-in input means C, by which the user can manually specify which part of the musical composition is to be accented.
And a facial expression adding means D capable of manually designating the fluctuation of the sounding timing, the addition of the ghost sound, and the fineness of the fill-in pattern.

Next, FIG. 2 shows a block diagram of one embodiment of the automatic facial expression adding device of the present invention. In FIG. 2, MID
In the data described in the I standard, the score of a music piece having at least a bass part is described.
Data is input to the rhythm pattern generation unit 1 and MIDI
A rhythm pattern is extracted for each beat from the pronunciation pattern of the sound of the bass part specified by the data. The drum pattern database 2 stores drum patterns indicating the configuration (size, type) of the drum as a rhythm instrument and the rhythmic feeling of the drum, and the drum patterns from this database 2 are stored in the performance pattern generation unit 3. Given.

The performance pattern generator 3 generates a performance pattern for drum performance based on the rhythm pattern generated by the rhythm pattern generator 1 and the drum pattern from the drum pattern database 2. The fill-in pattern database 4 stores the structure and type of fill-in, and which part of the music is to be accented. The fill-in pattern from this database 4 is given to the fill-in pattern generator 5.

The play-in pattern generated by the play- pattern generating section 3 is given to the fill-in pattern generating section 5, and the accent of the portion indicated by the fill-in pattern in the play pattern is emphasized. The facial expression database 6 stores facial expression data for changing the sound intensity and sound generation timing for the generated drum performance pattern. The facial expression data is given to the drum facial expression adding section 7. The expression is given to the performance pattern.

On the other hand, the base facial expression database 8 stores the base facial expression data for each beat, and this facial expression data is given to the base facial expression attaching section 9. The bass facial expression attaching section 9 attaches an expression such as the strength of the bass sound to the beat unit pattern of the MIDI data, and gives the pattern with the expression to the timing adjusting section 10. The timing adjusting section 10 is provided with information from the drum expression adding section 7 regarding how strong and at which time to pronounce each beat. Then, the timing matching unit 10 matches the sounding timing of the bass data with the sounding timing of the performance pattern of the drum with the expression generated by the drum expression adding unit 7. That is, the timing of sound generation is matched with the timing generated in the process of processing the drum data, based on the performance pattern in beat units.

The performance data of the bass with the expression thus given is given to the MIDI data generator 11. At the same time, the playing pattern of the drum with the facial expression generated by the drum facial expression adding section 7 is the MIDI data generating section 11
MIDI data that is given to all parts and is given an expression is generated. This MIDI data output is MIDI
It is sent to a standard sound source and played like a human live performance.

With the above-mentioned configuration, a rhythm pattern is extracted from the input MIDI data, a performance pattern is generated from the rhythm pattern and the accumulated drum pattern, and an accent at a required portion of the performance pattern is generated. The expression is added to the performance pattern by emphasizing the strength of the sound and adding ghost sounds and changes in the sound timing and duration.

On the other hand, the beat-based pattern of MIDI data is emphasized and given an expression of a bass sound by an instrument such as a bass other than a rhythm instrument such as a drum, and the expression-added pattern is used as the timing of the playing pattern of the drum. By matching them, it is possible to give a uniform expression to the whole song.

The rhythm pattern generating section 1 generates the rhythm pattern of each part from all the parts that depend on the input MIDI data. The rhythm pattern of which part of the rhythm patterns is adopted. Whether to do so can be specified by an external operation such as a keyboard using the specifying means A.

[0028] In addition, the play pattern generator 3, Starring on the basis of the rhythm pattern that has been generated by the rhythm pattern generating unit 1
While generating a response rate pattern by using a rhythm pattern input unit B on behalf of the rhythm pattern, playback pattern based on the rhythm pattern preferences entered by the user
It can generate over emissions. Then, this performance pattern generation unit 3
Can select either the rhythm pattern generated by the rhythm pattern generation unit 1 or the rhythm pattern input by the user. At this time, when the user selects a favorite rhythm, the performance pattern generation unit 3 takes the common term of the original rhythm pattern of the music generated by the rhythm pattern generation unit 1 and the rhythm pattern input by the user, and gives priority to the common rhythm. Rhythm pattern similar to the rhythm.

Further, the fill-in adding section 5 may be configured such that the user can select the fill-in position from the outside by using the fill-in input means C, which indicates which part of the music piece to be accented by the keyboard. Furthermore, in order to add an expression according to the user's preference, the expression adding means D can be used to specify the magnitude of fluctuation in the timing of sounding, the addition of ghost sounds, and the fineness of the fill-in pattern.

FIG. 3 is a block diagram showing a second embodiment of the present invention. In this embodiment, a plurality of musical instruments are used as musical instruments other than the rhythm musical instrument, and a guitar is used in addition to the bass. For this reason, the MIDI data describes the musical score of a musical composition having bass, drum, and guitar parts.

The guitar facial expression database 12 stores facial expression pattern data relating to a mute guitar, a clean guitar, etc., and the guitar facial expression adding section 13 adds facial expressions to MIDI data based on the guitar facial expression pattern. The expression given data given to the timing matching unit 10 together with data attached facial expression based expression attaching portions 9 described in FIG. 2, match the timing based on the play pattern of the drum.

Also in this embodiment, the strength and weakness of the sound, the length of the sound, and the ghost sound are added as the information to which the facial expression is added.

Therefore, in this embodiment, the MIDI data can be generated in a form very close to a live human performance of the bass and guitar parts at the timing of the performance pattern of the drum.

FIG. 4 is a block diagram showing a third embodiment of the present invention. This embodiment uses a bass, a guitar, and a saxophone as an instrument other than a rhythm instrument. For this reason, the MIDI data describes the score of a musical composition having parts of bass, drum, guitar, and saxophone. The saxophone facial expression database 14 stores data of saxophone facial expression patterns, and a saxophone facial expression adding section 15 is provided corresponding to the data. The saxophone facial expression adding unit 15 adds facial expressions to the MIDI data based on the saxophone facial expression pattern. The expression-added data is given to the timing adjusting unit 10, and is adjusted to the timing based on the performance pattern together with the expression-added data in the bass expression adding unit 9 and the guitar expression adding unit 13.

Also in this embodiment, as described above, the strength and weakness of the sound, the length of the sound, and the addition of the ghost sound are added as the facial expression information.

Therefore, also in this embodiment, the MIDI data can be generated in a form very close to a live human performance of the bass, guitar, and saxophone parts in accordance with the timing of the performance pattern of the drum.

FIG. 5 is a block diagram showing a fourth embodiment of the present invention. In the embodiments shown in FIGS. 2 to 4 described above, the parts of other musical instruments are matched to the timing of the playing pattern of the drum, whereas in this embodiment, the drums other than the saxophone are synchronized at the sounding timing of the saxophone. This is to match the sounding timings of all musical instrument parts including.

For this reason, the saxophone timing database 16 holds the pronunciation timing of the saxophone in phrase units. A phrase is an enumeration of sounds having a length of one beat to several bars that humans perceive as a melody constituent unit, and phrases are automatically recognized for input data. This automatic recognition will be described later. The sound generation timing data is given to the timing adjusting section 17. The timing adjustment unit 17 performs matching on a phrase-by-phrase basis in the same manner as with the expression of the saxophone data in the embodiment of FIG. 4, and at that time fetches the pronunciation timing of the human performance from the saxophone database 16. Then, the MIDI data generator 18 outputs the performance pattern as MIDI data at this sounding timing.

Here, the automatic recognition of phrases will be specifically described. Humans intuitively add "breaks" to the input music. The same facial expression is detected by the automatic facial expression adding device of the present invention.

FIG. 6 is a diagram for explaining a method of recognizing a phrase. As shown in FIG.
_{For each of 1} , P ₂ , P ₃ , the period with sound is D
₁ , D ₂ , D ₃ , each period D ₁ , D ₂ , D
Detects breaks between each of the _three .

[0041] FIG. 6 (b) shows a method of detecting a break in the actual music and including sound marks i phrases, expressions of conditions for detecting a delimiter is defined as follows.

A _i = P _i / P _i-1 , B _i = P _i -D _i
(Sound marks i is the beginning of the phrase), where the ratio of the sound interval P _i-1 of the previous A _i is to be sound interval P _i One, B _i is no certain sound interval P _i sound The period is shown. Here, the terms sound interval say, 1 Tsunooto marks and spacing (time) until the next note marks is heard in that, not fixed.

Then, (i), (ii), and (ii) in FIG.
In the example of i) and (iv), the one that satisfies any of the following conditions is a delimiter.

(I) A _i <0.5 and B _i-1 ≧
8 the length of the diacritic marks (ii) the length of the B _i-1 ≧ 4 diacritical marks (iii) A _i ≦ 0.15 and, the D _i-1 ≧ 2 diacritical marks
Length (iv) A _i <0.2 and B _i-1 > 0 In this embodiment, the sounding timings of other parts are matched with the sounding timing of the saxophone, but the timing database is not limited to the saxophone. Any musical instrument can be used as well.

As described above, according to each of the embodiments of the present invention, regarding the rhythm portion of the music, even if there is no drum part in the input data, if there is a part of another musical instrument, the music is suitable for a human-like performance. Drum parts can be automatically generated. Moreover, since the data used to add facial expressions is an actual live performance, MIDI data close to human performance data can be automatically generated. Furthermore, since the processing is automatic and the processing speed is high, real-time processing is possible.

Furthermore, since MIDI data is used, the amount of data is small, and it is suitable for distribution of music data via a network, and the performance data has the same quality as the sampling data of the performance data having a very large data size. Can be automatically generated with a small size of about 1 to 10% thereof, and the recording load on various recording media can be reduced.

The embodiments disclosed this time are to be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

[0048]

As described above, according to the present invention, a rhythm pattern is extracted from input MIDI data, and a performance pattern is generated based on a rhythm feeling held in advance and the extracted rhythm pattern. , MIDI data with a small amount of data is used because the expression of the musical instrument other than the rhythm musical instrument is added to the expression of the musical instrument, and the expression-added data is output at the timing based on the performance pattern. It can generate data that is close to human live performance.

Further, by inputting the rhythm pattern by the user, the original performance pattern and the rhythm pattern can be matched with each other, and further, the required portion of the performance pattern can be accented based on the user's request. You can

In particular, the user can set the rhythm expression preference, and when playing a plurality of musical instruments other than the rhythm musical instrument, it becomes possible to give a uniform expression to the entire song.
Performance data closer to a live performance can be obtained.

Further, it is possible to enable the performance of the entire tune based on the timing of the instrument to be lead.

[Brief description of drawings]

FIG. 1 is a block diagram showing a peripheral part of a device with automatic performance according to the present invention.

FIG. 2 is a schematic block diagram of an automatic facial expression adding device according to the first embodiment of the present invention.

FIG. 3 is a schematic block diagram of an automatic facial expression adding device according to a second embodiment of the present invention.

FIG. 4 is a schematic block diagram of an automatic facial expression adding device according to a third embodiment of the present invention.

FIG. 5 is a schematic block diagram of an automatic facial expression adding device according to a fourth embodiment of the present invention.

FIG. 6 is a diagram for explaining a method of recognizing a phrase.

[Explanation of symbols]

1 rhythm pattern generation unit, 2 drum pattern database, 3 drum pattern generation unit, 4 fill-in pattern database, 5 fill-in pattern generation unit,
Database with 6 drum expressions, section with 7 drum expressions,
8 base facial expression database, 9 base facial expression part,
10,17 Timing adjustment unit, 11,18 MID
I data generator, 12 database with guitar expression, 1
3 guitar facial expression part, 14 saxophone facial expression database, 15 saxophone facial expression part, 16 saxophone timing database.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsunori Shimohara, No. 5, Mihiratani, Osamu Osamu, Seika-cho, Soraku-gun, Kyoto Pref. JP-A-5 -73036 (JP, A) JP 5-297868 (JP, A) JP 5-323963 (JP, A) JP 6-348261 (JP, A) JP 8-263061 (JP, A) ) JP-A-8-305364 (JP, A) JP-A-9-81145 (JP, A) JP-A-10-222166 (JP, A) JP-A-57-67996 (JP, A) Practical application Sho-57- 115097 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G10H 1/00-7/12 G10K 15/04

Claims (4)

(57) [Claims] 1. A musical composition described in the MIDI standard is provided with an expression.
A device for automatically expressing a musical piece to be played, which is a rhythm showing the configuration of the rhythm musical instrument and the rhythmic feeling of the rhythm musical instrument.
Rhythm musical instrument pattern holding means for holding musical instrument patterns
And one or more musical instrument parts that comply with the MIDI standard.
From the part of the specific instrument in the MIDI data consisting of
Rhythm generating means for generating a first rhythm pattern, and a second rhythm pattern for inputting a second rhythm pattern preferred by the user.
It is held by the rhythm pattern input means and the rhythm instrument pattern holding means.
Rhythm musical instrument pattern generated by the rhythm generating means
First rhythm pattern and the rhythm pattern
Based on the second rhythm pattern input from the input means,
And a performance pattern generating means for generating a performance pattern
And putters for expression of one or more instruments other than rhythm instruments
Holding the facial expression pattern holding means and the facial expression holding pattern held by the facial expression pattern holding means
One of the MIDI data based on the
Or facial expressions for parts of multiple instruments
And a performance pattern generated by the performance pattern generating means.
MIDI with the above expression at the timing of pronunciation
Timing matching means for matching the sounding timing of the data, and the performance pattern generated by the performance pattern generating means.
And the timed expression is added.
New MIDI data based on
Expression of music with output means for generating and outputting
Attached device. 2. The performance pattern generating means is the first
Of the second rhythm pattern and the rhythm pattern of
Select one of them and select the first rhythm pattern and the second rhythm pattern.
The common rhythm of the rhythm pattern is extracted, and the common rhythm is extracted.
A rhythm pattern similar to the rhythm pattern selected from
To generate a turn, playing on the basis of the rhythm pattern
The automatic expression of the musical composition according to claim 1, which generates a pattern.
apparatus. 3. A musical composition described in the MIDI standard is provided with an expression.
A device for automatically expressing a musical piece to be played, which is a rhythm showing the configuration of the rhythm musical instrument and the rhythmic feeling of the rhythm musical instrument.
Rhythm musical instrument pattern holding means for holding musical instrument patterns
And one or more musical instrument parts that comply with the MIDI standard.
From the part of the specific instrument in the MIDI data consisting of
Held by the rhythm generating means for generating a rhythm pattern and the rhythm musical instrument pattern holding means
Rhythm musical instrument pattern generated by the rhythm generating means
Performance pattern based on the selected rhythm pattern.
The performance pattern generation means to be performed, and the user's fluctuation of sound intensity and sound timing of the rhythm musical instrument.
And the preference of facial expression patterns including ghost sounds
A facial expression with the pattern input means for inputting rhythm music input from the expressive pattern input means
Based on the preference of the facial expression pattern of the vessel, the performance pattern
The expression adding means for giving a desired expression to the musical instrument , and the expression adding pattern for one or more musical instruments other than the rhythm musical instrument.
A facial expression pattern holding means for holding a turn, and a facial expression pattern holding means for holding the facial expression pattern holding means .
One of the MIDI data based on the
Or facial expressions for parts of multiple instruments
Means and a performance pattern applied with the expression by the expression adding means.
MIDI with the above expression at the timing of pronunciation
Timing adjuster that adjusts the sounding timing of data
A stage and a performance pattern that is given a facial expression by the facial expression adding means.
And the timed expression is added.
New MIDI data based on
Expression of music with output means for generating and outputting
Attached device. 4. A musical composition described in the MIDI standard is provided with an expression.
A device for automatically expressing a musical piece to be played, which is a rhythm showing the configuration of the rhythm musical instrument and the rhythmic feeling of the rhythm musical instrument.
Rhythm instruments pattern holding means that holds a musical instrument pattern
And one or more musical instrument parts that comply with the MIDI standard.
From the part of the specific instrument in the MIDI data consisting of
Rhythm generating means for generating a rhythm pattern, held by the rhythm instrument pattern holding means
Rhythm musical instrument pattern generated by the rhythm generating means
Performance pattern based on the selected rhythm pattern.
Means for generating performance patterns and a putter for expression of one or more musical instruments other than rhythm musical instruments
Holding the facial expression pattern holding means and the facial expression holding pattern held by the facial expression pattern holding means
Of the MIDI data based on the key pattern.
Even if the facial expression pattern holding means is not provided,
Instruments other than the rhythm instrument in which
A table that gives an expression of the parts of the instrument that lead the performance
Phrases the emotional means and the pronunciation timing of the instrument that leads the performance
Timing holding means for holding in units, the MIDI data with the expression and the performance pattern
Phrase recognition means for recognizing a phrase of a tone and a pronunciation timing held by the timing holding means.
The MIDI data with the expression and the performance.
Match the sounding timing of the playing pattern in phrase units
Timing adjusting means, and the timed and faced MI
New based on the DI data and the performance pattern
And output means for generating and outputting various MIDI data
The phrase recognizing means sets the sounding interval P _i of the note i as D _i and sets the period during which the note i is present as D _i.
And then, when the _{A i = P i / P i} -1, B i = P i -D i
When any of the following conditions (i) to (iv) is satisfied,
Automatically recognizes the note i at the beginning of the phrase.
Emotional device. (I) A _i <0.5 and B _i-1 ≧ eighth note length
Is _{(ii) B i-1 ≧} 4 note minutes long (iii) A _i ≦ 0.15 and, D _i-1 ≧ note 2 minutes
Length (iv) A _i <0.2 and B _i-1 > 0