JP2621266B2 - Automatic composer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic music composition, and more particularly, to an apparatus for generating a variation of an original music composition.

[Background] Creating a variation of a given piece of music requires considerable musical knowledge and composition skills. Therefore, in order to realize a device for automatically generating a variation, it is necessary to incorporate music knowledge and its use ability into the device. Furthermore, since the variations are characterized by maintaining the basic character of the original song, the ability to evaluate the original song is also required for this type of automatic composer.

[Object of the Invention] An object of the present invention is to provide an automatic composer capable of automatically generating a variation from a given original music.

[Structure and operation of the invention] In order to achieve the above object, the present invention provides a melody input unit for inputting a melody of an original song, a chord input unit for inputting a chord progression, and a melody and a chord progression input. Arpeggio pattern extracting means for analyzing a melody for each section and removing a non-harmonic sound included in the melody to extract an arpeggio pattern (a pattern of a variance chord); and characteristic parameters of a non-harmonic sound of a variation And a non-harmonic sound applying means for applying a non-harmonic sound to the arpeggio pattern in accordance with the characteristic parameter.

The variation generated by the automatic composer has an arpeggio pattern similar to the arpeggio pattern of the melody of the original music. As a result, the character of the original song is reflected in the variation.

Further, no special music knowledge is required in using the automatic composer, and it can be easily used by ordinary people.

EXAMPLES Examples of the present invention will be described below.

<Overall Configuration> FIG. 1 shows the overall configuration of an automatic music composer according to the embodiment.
The CPU 1 is a control device for realizing a variation generation function in the present device. The melody and chord progression of the original music are input from the input device 2 and stored in the original melody memory 3 and chord progression memory 4, respectively. The scale data memory 5 is a memory for storing scale data representing various types of scales. Prior to generation of a variation, the user determines the type of scale to be used in the variation in the scale set of the scale data memory 5. You can choose from among them. The production rule data memory 6 stores music knowledge for classifying non-harmonic sounds. As will be described later, this music knowledge is used when a desired non-harmonic sound is given to the arpeggio. The pulse scale memory 7 is a memory for storing various pulse scales (sets of pulse scales). When a user instructs the apparatus to generate a variation, the user considers the characteristics of the rhythm given to the variation and takes into account this rhythm. A desired pulse scale can be selected from a set of pulse scales. The selected pulse scale is used for controlling the rhythm (length sequence) of the variation. The generated melody memory 8 stores data of the completed variation. The external storage device 9 is used as a copy of the variation data stored in the melody data memory 8, as another musical knowledge, and as a resource for another composition program. The work memory 10 stores various data and variables used during the operation of the CPU 1. monitor
Numeral 11 comprises a CRT 12, a staff notation printer 13, a musical tone forming device 14, and a sound system 15, which can output and display generated variations and the like through these devices.

<General Flow> The overall flow of this device in the variation generation mode is
Shown in the figure.

In the initial setting of 2-1, the user inputs basic information for generating a variation to the automatic musical composition. Here, (1) BEAT (2) Type of pulse scale and (3) Type of scale are shown as input information. BEAT is the length of one measure represented by the number of notes (resolution) of the basic unit length, and determines the time signature of a variation. For example, 4
If the basic unit length of a musical note is a sixteenth note for a musical piece of the meter system, by setting BEAT = 16, the length of one measure becomes four beats. The type of pulse scale set in 2-1 is used as information for controlling the rhythm of the variation. The pulse scale is a scale in which each pulse point having an interval of the basic unit length is weighted to indicate the ease of combining sound lengths or the ease of dividing sound lengths. The type of the scale selected in 2-1 determines the scale used in generating the variation.

In 2-2, data necessary for generating a variation is read. Necessary data are (1) the melody of the original music, (2) chord progression, (3) production rules, and (4) pulse scale data.

In 2-3, the characteristic of the non-harmonic sound to be given to the variation is set.

In 2-4, the chord progression is evaluated, where (1)
The tonality structure is extracted and the (2) scale for the special chord is determined.

The melody is changed in 2-5. That is,
(1) In the feature extraction, the rhythm and arpeggio pattern of the original music are extracted for each section (a measure or a section similar to a measure). (2) In the generation, an arpeggio of the melody of the variation is generated, and the generated arpeggio is generated. A non-harmonic sound according to the characteristics of the non-harmonic is added to the melody based on the production rules to generate a melody rhythm (length sequence).

<Variable list, data format> The list of main variables used in the flow described later
The data format is shown in FIG. 4 to FIG. The data format is merely an example, and any other appropriate data format can be used.

<Data Reading> As shown in the general flow of FIG. 2, after the initial setting, data reading is performed in 2-2. The reading of each data will be described below.

FIG. 10 shows an example of chord progression data stored in the chord progression memory 4 (FIG. 1). FIG. 11 is a flowchart for loading the chord progression data stored in the chord progression memory 4. In the memory map shown in FIG. 11, the code type (CDi) is located at an even address, and the length of the code is located at the next address (odd address).
For example, CDi with hexadecimal value of the display 507 represents the code G _7th, CRi code length with a value of 10 indicates that a 16 times the fundamental time length (e.g., sixteenth note) .

In FIG. 10, the register CDi contains the code appearing at the i-th position of the song to be composed, and CRi contains the length thereof.
CDNO contains the total number of codes. The other points are clear from the description of FIG. 10, and therefore the description is omitted.

FIG. 11 shows an example of pulse scale data stored in the pulse scale memory 7 (FIG. 1). FIG. 12 is a flowchart for loading the pulse scale of the type selected in the initial setting from the pulse scale memory 7. In this example, the pulse scale type (PUL) selected in the initial setting to select the rhythm characteristics of the song to be composed
S) indicates a specific address (for example, 0) in the pulse scale memory 7, and the address contains the start address of the selected pulse scale data. The start address stores the number of sub-scales (scales having only weights of 0 and 1) constituting the pulse scale, and data of each sub-scale is stored in the subsequent address. For example, the normal pulse scale has five sub-scales FFFF, 5555, 1111, 0101, and 0001.
(Hexadecimal representation) and the corresponding binary representation is shown in FIG. In the case of the normal pulse scale, the first pulse point (the rightmost position in FIG. 11) has a maximum weight of 5, which means that the rhythm generated when the normal pulse scale is selected. Indicates that a note is most likely to be present at the first position of each section (measure).

FIG. 13 shows the production rule data memory 6 (1st section).
2) shows an example of production rule data stored in FIG. FIG. 14 is a flowchart for reading the data stored in the memory 6. The entire production rule expresses musical knowledge for classifying non-harmonic sounds included in the melody, and each production rule data includes lower limit data Li and a function type as data that prescribes a premise of the rule. Function instruction data X to indicate
i, upper limit data Ui, and data Y as the conclusion of the rule
It has i and Ni. The function is a numerical representation of the feature of the melody to be analyzed, and an example is shown in FIG. 35 described later.
It is a premise (proposition) of the production rule that the value Fxi of the function represented by the data Xi is equal to or more than Li and equal to or less than Ui (Li ≦ Fxi ≦ Ui), and the conclusion when this premise is satisfied is data It is indicated by Yi, and the conclusion when this premise is not satisfied is indicated by data Ni. When the data Yi or Ni has a positive value, the value indicates the number of the next production rule to be referred in forward inference,
When it has a negative value, the type of the non-harmonic sound is represented by its absolute value. Forward inference always starts with one rule, and this rule is called a root. Forward finding ends when it finds a negative conclusion Yi or Ni.

In the case of the address assignment of the production rule data shown in FIG. 13, the data of each production rule is stored in five consecutive addresses starting from the address of the lower limit data Li. For details, Li is an address divisible by 5.
However, data Xi of the remainder 1 obtained by dividing by 5, Ui is stored at the address of the remainder 2, Yi is stored at the address of the remainder 3, and data of Ni is stored at the address of the remainder 4.

In FIG. 14, RULENO is set with the total number of production rules. The other points are clear from the above description and the description of the flow.

FIG. 15 shows an example of melody data stored in the original melody memory 3. FIG. 16 is a flowchart for reading the original melody data. In the case of FIG. 15, the pitch data MDi of the note is stored in the even address, and the pitch data MRi of the note is stored in the next odd address. MDN in Fig. 16
In O, the number of notes of the motif is set.

 This concludes the description of data reading.

<Characteristic setting of non-harmonic sound> In order to add a desired non-harmonic sound to the variation, the characteristic of the non-harmonic sound is set in 2-3 of the general flow. The details are shown in FIG. In this process, the monitor (CRT 12) displays a keyword corresponding to each non-harmonic tone type a to urge the user to input (24).
-2). Non-harmonic identifier a input by the user in the RSi array
(24-3, 24-6, 24-7). When the code EOI indicating the end of the input is read, the number of non-harmonics is put in RSNO and the flow exits (24-8).

Here, the characteristic of the non-harmony set {RSI}
Is different from the non-harmonic features of the original melody.

Note that the characteristic setting of the non-harmonic sound may be automatically performed.
This is realized, for example, by sequentially storing the non-harmonic tone identifiers selected by the random number generation means from the set of non-harmonic tone identifiers in the array {RSi}.

In addition, once a variation has been generated, when there is a portion that is not desirable for the user, the characteristic of the non-harmonic sound in that section may be reset and the variation melody may be generated again.

<Evaluation of Chord Progression> The apparatus of the present embodiment includes means for evaluating chord progression for generating a variation. In the chord progression evaluation, the tonality structure of the music is extracted. The tonality structure represents a change in tonality as the music progresses, and is used to select a key of a scale (scale) to be used in each section in generating a variation melody described later. As a result, it is possible to generate a variation with a tonality. Furthermore, in the chord progression evaluation, a scale process for using a special scale (a scale with little relation to tonality) is performed on the section where a special chord is used, regardless of the type of scale initially set. doing.

Hereinafter, extraction of the tongue structure will be described with reference to FIGS. 18 to 21. In order to extract the tonality structure from the chord progression, the present embodiment takes into account the properties of the tongue structure of general music. The characteristics are as follows: (a) The tonality tends to maintain the same tonality rather than changing frequently in the progress of the music.

(B) The constituent sounds of a chord are on a musical scale of a specific tonality.

(C) When transposition occurs, it is easier to turn to a close relative such as a genus key or a subordinate key than to an unrelated key.

It is.

In order to provide the tonality structure to be extracted with the above properties, in the present embodiment, a tonality distance is defined between the chords, and if the chord in the current section has a tonality of a predetermined distance from the tonality in the previous section. The tonality of the current section is considered to be the same as the tonality of the previous section.

FIG. 21 illustrates the tonal distance between the chords. As can be seen from this figure, codes having a parallel tone relationship (for example, Am
And C) are zero, and thus have the same tonality (C). In addition, the tonality distance from a chord that is completely 5 degrees below or completely 5 degrees (correlated chord) is 2 or −.
It is 2. Now, considering the datonic scale (doremifasoraside) of key C, the six chords of chords C, Am, G, Em, F, and Dm that are within a tonality distance of ± 2 from chord C have their chord constituent sounds. All are on the key C diatonic scale. As will be described later, in the present embodiment, the tonality is maintained for a chord change within the tonality distance ± 2.

In FIG. 18, in the processing from 48-1 to 48-5, tonality distance data is assigned to each code in the chord progression according to the definition of the tonality distance illustrated in FIG. That is, the tonality for the first chord of the song is
"0" is set as the KEY _1, is calculated by the 48-2～48-5, it calculates the distance tonality KEYi subsequent encoding CPi and tonality KEY ₁ the first code CD _1. The tonality of 48-3 is 20th
It is shown in the figure.

CDi∧ooff in 50-1 is an extract of the root data of the i-th code CDi (see FIG. 4), the result is assigned to a ₁ and a _2. On the other hand root data of the first code CD ₁ enters in st. As shown in 50-5, root data a ₁ is 50-3～50
-6 is turned up 5 degrees each time the circuit goes around the loop, and the root data of a ₂ is turned down 5 degrees (corresponding to turning the ring shown in FIG. 21 counterclockwise or clockwise). ). 50
At -3, a ₁ = st holds when the root data i of CDi is turned up 5 times, and at 50-4, a ₂ = st.
The condition “st” is satisfied when the root note data of CDi is turned 5 times below i. Therefore, for the former, ix (-2) is inserted into x as a tonality distance (50-7), and for the latter, x is ix2. 50-9 from 50-17 is, and code CDi of interest as the first code CD ₁ is, both or major system or minor system, by or not, is where you are converting the x. For example, Datosuruto CDi CD ₁ is in Am is Gmaj, (for comparison with root A and G) that x = has become + 4 by 50-7. This must be x = -2 according to FIG. In this case, in FIG. 20, 50-1
From 0 to 50-11, 50-13, x = -2 by x = x-6
Is obtained. Also, if CD ₁ is Cmaj and CDi is Bmin,
X = −10 by 50-8. This must be x = −4 according to the definition of the tonality distance in FIG. In this case, in FIG. 20, 50-14 or 50-15, 50-1
Proceeding with 7, x = -4 is obtained by x = x + 6. No. 2
The calculation result x in FIG. 0 is transferred to KEYi.

An example of the processing from 48-1 to 48-5 is shown in (1) of FIG. Chord progression _{C, C, F, G 7} , Bb, F, with respect to G _7, c, as tonality distance _{{KEY}, KEY 1 = 0} , KEY 2 = 0, KEY 3 = + 2, K
EY ₄ = -2, KEY ₅ = + 4, KEY ₆ = + 2, KEY ₇ = -2, KEY
₈ = 0 is obtained.

The tonality distance {KEY} obtained in this way is
In the processing from 6 to 48-14, conversion is performed so as to have the tonality property described above. That is, the previous tonality data is skey
Tongue data of the current chord
When the distance is within ± 2 from the skey, the tonality data of the current code is converted to the immediately preceding tonality data to maintain the tonality,
Is regarded as modulation only when the distance exceeds the value, and a value obtained by adding ± 2 to the tonality data of the current code is used as final tonality data.

The processing side from 48-6 to 48-14 is shown in (2) of FIG. Chord progression _{C, C, F, G 7} , Bb, F, as tonality for _{G 7, C {KEY},} 0,0,0,0,2,2,0,0 is obtained.

In this manner, a tonality structure having a desired property as a musical piece is extracted in the data format of the distance expression.

In FIG. 18, from 48-15 to 48-25, the tonality structure data of the distance expression is being converted into a pitch name expression representing the root of the scale. In this tone name expression, C is assigned a numerical value of “0”, C # is assigned a numerical value of “1”,. For example, assume that the first chord of a song is Cmaj, the i-th chord is Fmaj, and the tonality of this Fmaj is "2" in the distance expression. The corresponding pitch name expression is “5”. Because of this conversion, the process proceeds from 48-15 to 48-16, 48-17, where a
_{1 = KEY 1 -KEYi × 7/} 2 is performed, since it is _{KEY 1 = 0, KEYi = 2} a 1 = -7 next, a ₁ by the processing of 48-18,48-19
= 5, which is KEYi (48-20). If the first chord of the song is major, KEY ₁ = 00ff ＝ CD ₁
Gives the root of the scale of the first chord section,
In the case of a minor system, KEY ₁ =
(00ff∧CD ₁ +3) mod12 is executed to obtain the root note of the scale of the first chord section (48-16, 48-21 to 48-23).
FIG. 19 (3) shows an example of processing from 48-15 to 48-25. When chord progression is _{C, C, F, G 7} , Bb, F, G 7, C,
The scale key (tonic) used in each chord section is
C, C, C, C, F, F, C, C.

As will be described later, each tone of the melody generated in each chord section is selected from a scale using the tonality structure data extracted by the above processing as the main tone.

Next, the scale evaluation will be described with reference to FIG. The purpose of this processing is to use a special scale as a scale for melody generation for a section where a special code is used. In FIG. 22, ISCA
LE is the scale selected in the initial setting 2-1 (FIG. 2). If the code CDi is the deminish code "dim", set the combination deminish scale as the scale SCACEi to be used in that section, and set the code CDi
When i is an augment code "aug", set the whole tone scale as the scale, and when code CDi is the seventh code "7th", dominant as the scale
7th scale is set. As the tones of these chord sections, the root note of the chord is used instead of the tonality data obtained in the tonality structure extraction processing. Therefore, in a section other than these exceptional chord sections, a scale of the type selected in the initial setting is used as a scale, and its tonic is determined by tonality data obtained by the above-described tonality structure extraction processing.

<Melody Variation> FIG. 23 shows details of the melody variation executed in 2-5 of the general flow (FIG. 2).

First, after the section number i (measure number) is initialized to 1 (23-1), every time the loop (23-2 to 23-10) is completed,
A melody of one section is generated. The position information of the note of the original melody at the beginning and end of the section of interest is calculated (23-2), and only the harmony (chord component sound) is extracted from the original melody in that section, and the octave number and An arpeggio pattern represented by the chord constituent note numbers is generated (23-3). Furthermore, the original melody norism in that section is also extracted (23-4). The extracted arpeggio pattern is in the form of melody data (pitch train expression form)
(23-5), a non-harmonic tone is added to this melody data, and the pitch sequence of the melody of the variation is completed (23-6). Subsequently, a melody duration sequence is generated (23
-7). Here, the rhythm pattern of the original melody extracted in 23-4 is transformed by the pulse scale selected in the initial setting 2-1. When the generated variation melody data is moved to the continuous area (23-8), the section counter i is incremented to generate the variation melody for the next section (23-9), and when the end of the chord progression is detected. (23-1
0), the variation melody for the previous section has been completed.

Details of the calculation 23-2 of Ps, Pss, Pe, and Pee are shown in FIGS. 24 to 26. Ps indicates the number of the first note of the target bar in the original song, Pss indicates the length of the note extending beyond the previous bar, and Pe indicates the position of the last note of the target bar. , Pee represent the length of the note following Pe, that is, the length of the note at the beginning of the next bar interrupting the target bar.

In the flow of calculating Ps and Pss in FIG. 25, beat represents the length of one measure (basic time length expression), and bar represents the number of the target measure. If the measure number is smaller than 1 or greater than the number of measures (mno) in the song, it is an input error. If the specified measure is 1, set Ps = 1 and Pss = 0 (27-4, 27-
Five). The reason for Ps = 1 is that, in the case of the first bar, the first note of the bar is nothing but the first note of the original music, and the reason for Pss = 0 is that there is no preceding bar. A ₁ obtained in 27-2 is the length from the beginning of the song to the bar at the front of the target bar, and this length a ₁ was obtained by accumulating the original melody note length data MRi from the beginning Compare with the length S (27-7, 27-8, 27-10, 27-12). When S = a ₁ holds, the next note of the i-th pitch data finally accumulated in S starts from the beginning of the target bar. Therefore Ps
= I + 1, Pss = 0 (27-9). On the other hand, when S> a ₁ holds, the note having the note length data added last to S, that is, the i-th note is the first note of the target bar. Therefore, Ps = i. Also, Pss = MRi-S +
Set to a ₁ (27-9).

The calculation flow of Pe and Pee shown in FIG. 26 performs processing very similar to that of FIG. However the length of the beginning of the song to the rear bar line of the target bar enters the a _1, the description thereof is omitted for other points.

Details of the extraction of the arpeggio pattern shown in 23-3 are shown in FIG. Here, the arpeggio pattern {LLi} is extracted from the original melody of the target bar. To summarize the processing, for the measure indicated by Ps and Pe, the corresponding chord in the chord progression information is used to determine whether the original melody note is a harmony, and the sound determined to be a harmony For, the corresponding chord constituent sound is searched out from the chords to obtain data in the form of LL. More specifically, first, constituent sound data is generated from the chord data of the current bar (29-2). , FIG. 28, FIG. 29). As shown in FIG. 28, the chord constituent sound data memory stores chord constituent sounds as data of lower 12 bits in 16 bits for each type of chord having the root note as C. Each bit position represents each note name,
The lowest bit position is C (C). For example, cc = 00
91 (hexadecimal) has "1" in the bit positions of de, mi, and so
Represents the constituent sounds of the major. Now, assuming that the code of the target section is Gmaj, the CD is 0007 (hexadecimal). From the chord structure sound data memory, the major chord structure sound data cc (= 00) at the address specified by the upper 8 bits of the CD
91), and the lower 12 bits are turned to the left by the root value indicated by the lower 8 bits of the CD as shown in FIG. 31. Moving to positions 7, 11, and 2, the chord components of Gmaj are expressed. In this way, chord constituent sound data is generated from the chord of the target section. Next, the scale counter i and the harmony sound counter k are initialized (29-3, 29-4). The process of 29-5 is a process of converting the pitch data MDi of the motif into the same data formation as the chord configuration sound data cc. For example, "so"
Is converted into data mm having "1" in bit position 7.

At 29-6, it is checked whether or not this pitch data mm is a chord component sound. This can be determined by taking the logical product (mm∧cc) of the pitch data mm and the chord constituent sound data cc.
In 29-7 to 29-13, bit “1” of chord constituent sound data cc
, The octave number (MDi∧ffoo) of the motif sound is added to c, and the arpeggio pattern data is determined. LLk. At 29-15, the counter i is advanced to the next note, and until the note number reaches Pe (29-1
6) Find LL. The number of harmony sounds (length of the arpeggio pattern) in the target section is entered in LLNO of 29-17.

 Details of the rhythm evaluation 25-4 are shown in FIG.

In the rhythm evaluation of FIG. 25, rr shown in 25-2 is a 16-bit register for storing the rhythm pattern of the target bar, and when the length of one bar is 16, the first bit position of the register rr is The Nth bit position represents the first elementary time of the measure, and similarly the Nth bit position represents the Nth elementary time from the beginning of the measure. In the processing from 25-3 to 25-9, the positions of the notes from the note Ps of the motif to the note Pe are converted to the motif note length data MR.
This is a process of obtaining using i and writing in the corresponding bit position of the register rr. For example, if a result of 0001000100010001 is obtained as rr, this pattern rr indicates that a sound is generated at the first beat, second beat, third beat, and fourth beat of the target bar.

FIG. 31 is a detail of 23-5 in FIG. The purpose is to convert the format of the arpeggio pattern LL indicated by (octave number + chord component number) to the format of melody pitch data indicated by (octave number + note name number) using the chord component sound data cc. And store it in MEDi.
The processing of 58-5 and 58-6 is based on the LLi chord constituent note number (LLi∧00
When ff) is greater than the number of chord constituent sounds (CKNO) of the chord in the current section, the LLi chord constituent note number is changed to the highest chord constituent note number among the chord constituent sounds in the current section. In the figure, c is a counter of chord constituent sounds, LLi∧f
f00 is an LLi octave number, and j is a note name counter.

The arpeggio pattern {LL} used here is
It does not have to be completely the same as the arpeggio pattern extracted from the original melody. For example, it is possible to use the extracted arpeggio pattern {LL} that is turned up or down. For example, as {LL}, (0401,0303,
When 0302, 0301) is extracted, the pattern of (0402, 0401, 0303, 0302) can be obtained by turning one upward. Alternatively, only one of the extracted elements of the arpeggio pattern {LL} may be changed to other data.

FIG. 32 and FIG. 33 show details of the non-harmonic sound addition in step 23-6 in FIG. The purpose of this processing is to add a desired non-harmonic sound to the arpeggio to complete the pitch sequence of the melody. For the addition of non-harmonic tones, the above-mentioned non-harmonic features {RSi}, tonality structure {KEYi} obtained by chord progression evaluation,
Production rules are used to express the knowledge to classify non-harmonic sounds. The added non-harmonic tone must satisfy the following conditions.

(B) The sound must be within a predetermined range. (B) The sound must be on a scale with the KEYi obtained in the chord progression evaluation as the main tone. (C) It must be a sound outside the chord structure. In FIG. 32, the loop outside of 59-4 to 59-18 is a loop that repeats for the number of planned non-harmonic identifiers RSi, and FIG. The loop from -5 to 59-16 repeats the number of notes in the arpeggio. In 59-8 to 59-14, as non-harmonic candidate,
Each pitch data k in the range from the lower limit lo to the upper limit up is sequentially examined (see FIG. 34). When the pitch data k is a scale tone and a sound outside the chord configuration (59-8, 59-9),
Calculate the function F (59-10), perform forward inference based on the production rules (59-11), and check whether the conclusion matches the planned non-harmonic identifier RSi (59-11). . When they match, the pitch data k satisfies all of the above-mentioned conditions for non-harmonic sounds. Therefore, the non-chord tone counter nctct for counting the number of non-harmonics to be added is incremented, the pitch data k of the found non-harmonics is put in VMnctct, and the addition position j of the non-harmonics is set in POSTnctct. And the related flag fl _j is set to “1” (59-19 to 59-22). In this example, at most one non-harmonic sound is added between harmonic sounds.
fl _j = 0 indicates that a non-harmonic sound has not yet been added between the harmony sounds MEDj and MED _{j + 1} .

If the condition of the conclusion = RSi in 59-12 is not satisfied, since the pitch data k of interest does not satisfy the condition as a non-harmonic tone, the pitch data k is incremented (59-1).
3), repeat the process. When k> UP is satisfied in 59-14, it means that a non-harmonic tone has not been added between the harmonics MEDj and MED _{j + 1} . Therefore, j is incremented (59-15), and the process proceeds to a check as to whether a non-harmonic sound can be added between the next harmonic sounds.

Details of the setting of candidate sounds in 59-6 are shown in FIG. In this example, the pitch is searched from 5 semitones higher than the higher tone of the preceding and following harmony notes MEDj and MED _{j + 1} to 5 semitones lower than the lower tone (62-5 to 62-7). ). However,
When i = 0, that is, when trying to add a non-harmonic sound before the first harmony in the section of interest, the pitch range is from 5 semitones to 5 semitones below the first harmony. 62-1, 2), when i = Vmedno, that is, when an attempt is made to add a non-harmonic sound after the last harmony in the section of interest, the fifth to fifth semitone lower than the last harmony The pitch range is set (62-3, 4).

The details of checking whether or not the pitch data k in 59-8 is a scale tone are shown in FIG. SCALEi in the figure indicates the type of the scale used in the section i, and is an address pointer of the scale data memory 5 as shown in FIG. The 12-bit scale data * SCALEi at this address is turned by the KEYi obtained in the above-described chord progression evaluation (65-2). For example, when SCALEi is “0” (diatonic scale), the data represents Doremifasoraside having C as a main tone. When KEYi is “5” (F), the data is converted into scale data a having F as the tonality by inverting the data five times. 65-3 is pitch data k (indicated by MD in the figure)
Is the process of converting to the same data format as the scale data,
As a result, if the logical product of b and the scale data a is "0", it is concluded that the pitch data k is not a scale sound, and if the logical product is not "0", it is concluded that the scale data is a scale sound (64-5 to 64). -7).

Details of the calculation of F in 59-10 are shown in FIG. In this example, since only one non-harmonic sound is added between the preceding and succeeding harmonic sounds, some functions (F _{1 to} F _{3 in the} figure) are set to predetermined values.

Details of the forward inference of 59-11 are shown in Figure 39. The purpose here is to infer using a production rule what kind of non-harmonic tone the pitch k of the non-harmonic candidate is. First, the rule number pointer P is set to "1" indicating the rule that is the root of the production rules (44-1). Thereafter, it is checked whether or not the prerequisite part (Lp ≦ Fxp ≦ Up) of the rule indicated by the rule number pointer P is satisfied, using the function value obtained by the calculation of F. The data Yp of the part is used as a pointer to the rule to be accessed next (44-2, 44-3, 44-5, 44-7). Pointers to rules to be referred to (44-3, 44-4; 44-5, 44-6; 44-7).
However, when the data Yp and Np are negative values, there is no rule to continue the inference, and the final conclusion indicating the type of the specific non-harmonic sound has been reached, so the absolute values (−Yp, −Np) are calculated. Set in the conclusion register (44-8, 44-9). As described above, in order for a non-harmonic candidate (pitch k) to be adopted as a non-harmonic sound, the conclusion of forward inference for this candidate must match the planned non-harmonic sound identifier RSi. is necessary.

When the processing in FIG. 32 is completed, the total number of added non-harmonic sounds is stored in nctct, and the i-th in the array {Vi} includes
The pitch data of the non-harmonic tone added i-th in the processing of FIG. 32 is stored, and the i-th of the
The position information of the i-th non-harmonic sound added in the processing of the figure is stored.

These data are converted into the melody pitch sequence {VMEDi} by the processing of FIG. Array ｛VME
Di｝ is initially set to arpeggio {MEDi}. 60
-2 to 60-9 are in the order of the addition position, array {POSTi}, {VMi}
Is the process of sorting In 60-10 to 60-19, the pitch data VMi of the non-harmonic tone is located at the position indicated by the position data POSTi.
Is inserted.

In this example, only one non-harmonic sound can be added between the harmonious sounds, but the processing may be changed so that a plurality of non-harmonic sounds can be added.

At this point, the pitch sequence of the melody is completed. The remaining processing is generation of a melody duration sequence.

Fig. 40 shows the flow of melody note length generation (23
-7 details). First, the number of notes of the reference rhythm pattern obtained in the rhythm evaluation of the original melody is compared with the number of notes Vmedno (the number of data in the pitch sequence of the melody) generated in the section of interest, and the difference a Is calculated (66-1). When the number of generated notes is smaller than the number of notes in the reference rhythm pattern (a
> 0), the optimum combination of notes by the pulse scale is repeatedly executed by the number of differences (66-2 to 66-6). When the number of generated notes is larger than the number of notes of the reference rhythm pattern (when a> 0), the optimum division of the notes is repeatedly executed by the difference (66-7 to 66-11). In this example, 16-bit data is used as the rhythm pattern data format.
Each bit position is assigned to each timing, which indicates that sound is generated at the bit position having a value of "1".
Finally, the data is converted to the MER data format (66-12).

Details of the combining process are shown in FIG. In the figure, PSCALEj represents the j-th component scale of the pulse scale to be used, and RR is a rhythm pattern to be processed. Notes are combined by setting the point with the smallest pulse scale weight to "0" in the bit of RR "1". For example, if the reference rhythm pattern is , And when one note is combined using the normal no pulse scale (see FIG. 7), the result is Becomes

 This is obtained as follows.

First, RR is initially 0001 0001 0101 0001. On the other hand, the normal pulse scale is 1213 1214 1213 1215. The point where the normal pulse scale has the minimum weight among the bits “1” of the RR is the seventh position from the right end. The bit at this position becomes “0”. Thus, the resulting RR is 0001 0001 0001 0001, which is Is represented.

Details of the dividing process are shown in FIG. The division is performed by setting the point at which the weight of the pulse scale is maximum to "1" among the bits of RR "0". For example, rhythm pattern On the other hand, when dividing notes with the normal pulse scale, the result is Becomes

Details of the conversion to the MER data format 66-12 are shown in FIG. 69.
In the figure, c ₁ is the counter of a note, c ₂ is a counter that measures the sound length of each note. In this example, MERo has a length until the first "1" appears from the RR, so it is possible to process notes that cross the section boundary (bar line) (measures against syncopation).

Note that in the note length data generation of FIG. 40, note combining or dividing processing is performed by the difference between the number of notes of the original melody of the section of interest and the number of notes of the melody of the variation.
It is not limited to this. For example, even when the number of notes in the original melody is equal to the number of notes in the melody of the variation, the rhythm pattern of the original melody is subjected to N-note combination processing and N-note division processing using a pulse scale, The result may be used as a rhythm pattern of a variation. In short, the number of notes in the melody of the variation is maintained, but the process of dividing and combining an arbitrary number that reaches the number of notes can be converted from the rhythm of the original melody to the rhythm of the melody of the variation. it can.

Details of the data movement 23-8 are shown in FIG. First, MERo
(The blank portion at the beginning of the current generation section) is added to the duration data MELRmeldno of the last generated note. Here, meldno represents the number of notes already generated. Move the pitch sequences VMED _{1 to} VMEDvmedno generated this time to MELD, and move the pitch sequences MER ₁ to MERvmedno generated this time to MELR (70-2 to 70-
6). Update meldno and exit (70-7).

<Summary> The automatic composer of this embodiment has various features for generating variations. Some of them are shown below.

(A) In order to evaluate the original music, an arpeggio pattern extracting means for extracting an arpeggio pattern in which non-harmonic sounds are removed from the melody of the original music for each section is provided.

(B) Each extracted arpeggio pattern (or a similar pattern) is used as an arpeggio pattern for each section of the variation.

(C) A non-harmonic sound feature setting means for setting a characteristic of the non-harmonic sound is provided for the variation.

(D) Tonality extraction means for extracting the tonality structure of the variation from the given chord progression is provided.

(E) A non-harmonic tone is added to an arpeggio pattern using music knowledge (production rules), taking into account the tonality structure and the characteristics of the non-harmonic tone. Accordingly, a musically appropriate non-harmonic sound is given.

(F) In order to evaluate the original music, a rhythm pattern extracting means for extracting a rhythm pattern of the original music for each section is provided.

(G) The extracted rhythm pattern is converted into a rhythm pattern of a variation by the rhythm control means on a pulse scale.

[Effects of the Invention] As is clear from the above description, the automatic composer of the present invention uses the arpeggio based on the given chord information from each section of the melody of the original music to evaluate the characteristics of the original music. Arpeggio pattern extracting means for extracting a pattern, characteristic parameter setting means for setting characteristic parameters of a non-harmonic sound of a variation, and non-harmonic sound providing means for applying a non-harmonic sound to the arpeggio pattern according to the set characteristic parameters. It has. Therefore, it is possible to automatically generate a variation having characteristics of the original music. Further, for the user who uses the automatic composer, special music knowledge is not required and the burden is small. This automatic composer is very effective not only as a hobby but also as a music education tool.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an automatic music composer according to an embodiment of the present invention, FIG. 2 is a flowchart showing an overall operation of the embodiment in a variation generation mode, and FIG. Diagrams showing a list of various variables, FIG. 4, FIG.
6, 7, and 8 are diagrams showing the format of data used, FIG. 9 is a diagram showing an example of chord progress data stored in a chord progress memory, and FIG. Reading flowchart, FIG. 11 is a diagram illustrating pulse scale data stored in a pulse scale memory, FIG.
FIG. 12 is a flowchart of reading pulse scale data, FIG. 13 is a diagram exemplifying production rule data stored in a production rule data memory, FIG.
FIG. 15 is a flowchart of reading the production rule data, FIG. 15 is a diagram illustrating melody data of the original music stored in the original melody memory, FIG. 16 is a flowchart of reading the melody data, and FIG. Flowchart for setting features, FIG. 18 is a flowchart for extracting a tonal structure from a chord progression, FIG. 19 is a diagram illustrating an extraction process of a tonal structure, and FIG. 20 is a diagram illustrating the first codes CD ₁ and i
FIG. 21 is a flowchart for calculating a tonality distance between the second code CD _{i and} FIG. 21.
The figure shows a flowchart of scale (scale) processing.
Figure 23 is a flowchart of the melody variation, and Figure 24 is Ps, P
e, Pss, Pee calculation flowchart, FIG. 25 shows Ps, Pss
26 is a flowchart for calculating Pe and Pee, FIG. 27 is a flowchart for extracting an arpeggio pattern from an original melody, and FIG. 28 exemplifies chord constituent sound data stored in a chord constituent sound memory. Figure,
29 is a flowchart for generating constituent sound data from chord data, FIG. 30 is a flowchart for evaluating the rhythm of an original melody, FIG. 31 is a flowchart for converting an arpeggio pattern to a melody data format, FIGS. 32 and 33 Is a flowchart for adding a non-harmonic sound to the arpeggio,
FIG. 34 is a diagram showing the order of non-harmonic sound addition processing, FIG. 35 is a flowchart for setting a pitch range as a non-harmonic candidate, FIG. 36 is a flowchart for calculating a function F, and FIG. 37 is a scale. FIG. 38 is a flowchart showing an example of scale data stored in the data memory, FIG. 38 is a flowchart for identification of chromatic tones, FIG. 39 is a flowchart for inference of non-harmonic tones by a production rule, and FIG. Flowchart for generation, Fig. 41 is a flowchart for optimal combination of notes, Fig. 42 is a flowchart for optimal division of notes, Fig. 43 is a flowchart for converting the generated rhythm pattern to MER data format, and Fig. 44 is a flowchart for the generated melody. It is a flowchart which moves data to a continuous area. 1 ... CPU, 2 ... input device, 3 ... original melody memory, 4 ... chord progression memory, 6 ... production rule data memory, RSi ... non-harmonic features, LLi ... arpeggio pattern.

Claims (1)

(57) [Claims] 1. An automatic composer for generating a variation of an original music, a melody input means for inputting a melody of the original music, a chord progression input means for inputting a chord progression, and a melody based on the melody and the chord progression. Arpeggio pattern extraction means for extracting an arpeggio pattern from the melody of each section without the non-harmonic sound; feature parameter setting means for setting the characteristic parameter of the non-harmonic sound of the variation; and A non-harmonic sound applying means for imparting a non-harmonic sound to the arpeggio pattern.