JP3134417B2 - Automatic accompaniment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a music apparatus and, more particularly, to an automatic accompaniment apparatus for judging the tonality of chord progression and performing automatic accompaniment based on the judgment result.

[0002]

2. Description of the Related Art Electronic musical instruments having an automatic accompaniment function are already known. This type of electronic musical instrument is roughly divided into two types: an accompaniment that forms accompaniment according to the chord route and type, and an accompaniment that uses chord tonality (keynote, function, and type).
According to the type. The former has a drawback in that the generated accompaniment is mixed with a sound that is unfavorable in tonality. The latter requires a means for analyzing the chord progression and extracting the tonality of each chord, but the accompaniment to be generated can be kept to a certain degree of natural tonality.

[0003] One important problem with the formation of accompaniments is to perform natural and varied accompaniment while saving storage capacity for accompaniment data. Unfortunately, this task has not been satisfactorily achieved with any of the prior art.

For example, as a root / type automatic accompaniment forming technique, an accompaniment pattern suitable for a reference route and a type is stored, and each accompaniment pitch data included in the reference accompaniment pattern is corrected according to the type. It is known to add a route to the correction result. According to this,
Although the storage capacity is small, the generated accompaniment lacks naturalness. There is also known an automatic accompaniment forming technique of a tonality method in which accompaniment patterns are prepared for each type of accompaniment rhythm and for each type of tonality, and the corresponding accompaniment pattern is selected and played back during operation. According to this technique, real and varied accompaniment can be performed, but the data amount of the accompaniment pattern becomes enormous, and it is difficult to realize the accompaniment pattern with a microcomputer having one to several chips.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an automatic accompaniment apparatus capable of realizing natural and realistic accompaniment with a small storage capacity.

[0006]

According to the present invention, a chord progression giving means for giving a chord progression, a tonality judging means for analyzing the chord progression and judging the tonality of each chord, An accompaniment forming means for forming an accompaniment based on the selected tonality, wherein the accompaniment forming means includes a reference accompaniment pattern storage means for storing an accompaniment pattern for a reference tonality, and the determined tonality. An accompaniment pitch changing means for changing each accompaniment pitch included in the accompaniment pattern read from the reference accompaniment pattern storage means to form the accompaniment pattern for the reference accompaniment pattern. The accompaniment pitch is changed so that the accompaniment pitch of the same pitch class included in the read accompaniment pattern becomes the accompaniment pitch of a different pitch class for the tonality different from the tonality of Automatic accompaniment apparatus is provided which comprises a means that.

According to this configuration, natural tonality accompaniment can be achieved by the operation of the tonality determining means. Further, by using the reference accompaniment pattern storage means, it is possible to save the data amount required for forming the accompaniment. Furthermore, since the accompaniment pitch changing means includes means for converting the accompaniment pitch of the same pitch class included in the accompaniment pattern of the reference tonality to the accompaniment pitch of a different pitch class according to the judgment tonality, the same It is possible to achieve a desired pitch conversion that cannot be obtained by simply converting the accompaniment pitch of the pitch class to another accompaniment pitch of the same pitch class according to the judgment tonality. Can be performed.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a functional block diagram of an automatic accompaniment device according to the present invention. From the chord progression input device 1, a chord progression representing each chord by a route and a type is input. The key / function determination unit 2 uses the chord progression as the music knowledge of the chord progression stored in the CP knowledge base 3 (knowledge of the chord pattern for maintaining the key, knowledge of the chord pattern indicating the modulation, etc.).
To determine the function name (function and type) and keynote as the tonality of each chord. The reference accompaniment pattern memory 4 stores an accompaniment pattern for the reference tonality. Element P of each accompaniment pitch included in this accompaniment pattern
Is accompanied by index information PP. The pitch change table memory 5 stores pitch change data for each combination of index information PP and function name. In order to select a specific pitch change data element, the address generator 6 stores the function name from the key / function determiner 2 and the reference accompaniment pattern memory 4.
, And generates an address designating a specific pitch change data element. In this way, the pitch change data $ P output from the pitch change table memory 5 is defined as a function f of a function name and index information (function name, PP). It should be noted that this function ΔP is independent of the accompaniment pitch P in the reference accompaniment pattern. By utilizing this independence, it is possible to convert accompaniment sounds of the same pitch or the same pitch class in the reference accompaniment pattern to accompaniment sounds of different pitches or different pitch classes. That is, the pitch change data {P output from the pitch change table memory 5
Is added to the accompaniment pitch data P of the reference accompaniment pattern by the adder 7, thereby obtaining an accompaniment whose pitch content freely changes in accordance with the function name. The output of the adder 7 is added to the key note from the key / function judging section 2 by the transposing adder 8, and becomes the actual accompaniment sound pitch transposed by the key note.

The configuration shown in FIG. 1 realizes real and varied accompaniment with a small storage capacity, and is particularly advantageous for an automatic accompaniment apparatus that accompanies many music styles.

If a memory for storing an accompaniment pattern for each combination of a function name and a music style is used, the data amount becomes enormous. For example, if the type of function name is 2
If the style is 0 and the style type is 40, 800 accompaniment patterns are required. The number of parts in a set of accompaniment patterns is 4
If the normal, intro, fill-in, ending, and fill-in patterns are individually prepared, the data amount of each pattern is considered to be about ＫK bits, and the total data amount is ×× 4 × 4 × 800 = 3200K Bits, and a memory of 3 M bits or more is required. This is a capacity that is difficult to realize with a current one-chip microcomputer. On the other hand, if the configuration of FIG. 1 is used,
The reference accompaniment pattern memory 4 only needs to store 40 sets of accompaniment patterns, and the pitch change table memory 5 need only prepare 40 sets of style-specific pitch change data sets.

FIG. 2 is a block diagram of hardware of an automatic accompaniment apparatus according to a specific embodiment. The CPU 100 controls the entire automatic accompaniment device. CPU in the ROM 102
100 programs to be executed and fixed data (chord progression music knowledge base, reference accompaniment pattern memory by style,
(Including a pitch change table memory for each style). The RAM 104 is used as a work memory under the control of the CPU 100. The input device 106 includes a keyboard for inputting a melody and a code, and panel switches. The panel switches include a start / stop switch for automatic accompaniment, a tempo volume, and a style designation switch. The tone generator 108 generates a melody and accompaniment digital tone signal under the control of the CPU 100. The sound system 110 includes a DAC, a filter, an amplifier, and a speaker, receives a tone signal output from the tone generator 108, and emits the sound to the outside. The timer 112 counts the elapse of a predetermined time and gives the CPU 100 a timer interrupt signal for activating the interrupt routine (FIG. 4).
The display device 114 can display a chord progression, a function progression corresponding to the chord progression, a key note progression, and the like.

FIG. 3 shows a main flow of the operation of the CPU 100 of FIG. CPU 10 at power-on
0 initializes the system. Step 3 of the main loop
At -2, the CPU 100 performs a key scan of the input device 106 in a normal manner. In step 3-3, the CPU 100 executes a style input process when there is an input from the style designation switch. In step 3-4, the CPU 100 controls the tone generator 108 based on the melody key information input from the keyboard to generate a melody sound. In step 3-5, the CPU 100 controls the display device 114 to display required data and messages.

FIG. 4 shows a timer interrupt routine which is periodically started by the timeout of the timer 112 and executed by the CPU 100. 4-1 and CP
U100 examines the accompaniment key information (taken in by key scan 4-2) and determines the type and route of the designated chord in a known manner. When a new code is detected (4-2), the CPU 100 executes the key note / function determination routine 4-3 to determine the function of the new code and the key note. In the accompaniment processing routine 4-4, the CPU
100 generates accompaniment data based on the designated music style, the function of the current chord, and the key note, and controls the musical sound generator 108 to generate an accompaniment sound signal.

FIG. 5 shows details of the key note / function determination routine 4-3. Key note / function determination routine 4-3
Analyzes the ongoing chord based on the chord progress knowledge base located in ROM 102 and determines its keynotes and functions. The chord progression knowledge base shows the same key note keeping code table that stores a set of codes that keep the key notes the same, a parallel code sequence table that stores a set of code patterns that indicate a change to parallel, and a pivot modulation. A modulation code sequence table for storing a set of code patterns and a code type / function correspondence table for directly converting code types to code functions are included.

First, at 5-1 the CPU 100 checks whether or not the current key note is determined. If the current key note is determined, the function name of the new code is generated using the current key note in 5-2. In step 5-3, the CPU 100 searches the same key note maintaining code table, and checks whether the same function name as the new code obtained in step 5-2 is entered in the table. If an entry has been made (Y at 5-4), the assumption at 5-2, that is, the assumption that the key note of the new code is the current key note, is correct, and the function name of the new code is determined.

If the search for the same key note maintaining code table fails, the CPU 100 converts the code immediately before to a function name based on the current key note in 5-5. Then C
The PU 100 searches the parallel tone code sequence table for a function code pattern including the function name of the immediately preceding code and the function name of the new code (5-6). If this search is successful (Y in 5-7), a change to parallel minor between the same key signatures has been confirmed, and the key note and function name of the new chord are determined.

If the search of the parallel tone code sequence table fails, the CPU 100 executes a pivot modulation inspection routine 5-8 to check the possibility of modulation. In this routine 5-8, the immediately preceding code is regarded as a pivot code, a function name of the immediately preceding code and a new code is generated based on each related key note, and a pivot modulation code sequence table is searched for the generated function name.

When the modulation is detected by the pivot modulation inspection (Y in 5-9), the corresponding key note corresponding to 5-10 is determined as the key note of the new code. If the pivot keying test fails or the current key note is indeterminate, execute step 5-11 and look up the code type / function correspondence table with the new code type to find the function name and key of the new code. Determine notes. In this way, as the execution result of the keynote / function determination routine,
The function name (function and type) and key note of the new code are determined.

FIG. 6 is a flow chart of the style input processing 3-3. When there is a style key input (6-1), the CPU 1
00 stores the number of the music style specified by the input, and selects the accompaniment pattern corresponding to the specified style (6-2).

FIG. 7 shows an example of data of a reference accompaniment pattern for a rhythm & blues music style as AM (R & B). The example in the figure is the accompaniment data used at the time of normal (nrm). In addition, the intro, fill-in,
There is ending accompaniment data, which is used as needed during rhythm & blues accompaniment. Accompaniment parts are the first part (C1), the second part (C2), the third part (bass part II), and the fourth part (rhythm part r).
Consists of G5, D5, A # 4, D5, etc. are the accompaniment pitch data. Each accompaniment pitch data is based on the standard tonality (C
Major). As shown in the figure, each piece of accompaniment pitch data is accompanied by index information (PCT No.) indicated by rt6, rt7, rt8, and the like. As will be described later, these pieces of index information are used in the pitch change table PCT to change accompaniment pitch data to which index information has been added. Note that the accompaniment pitch data is omitted from the reference accompaniment pattern memory of the actual device, and the reference accompaniment pattern memory is an accompaniment rhythm memory that stores the sounding timing information and index information of each sound of the accompaniment.

FIG. 8 shows a pitch change table PCT (R & B) of the pitch change table PCT relating to the music style "rhythm &blues". The row of the rhythm & blues pitch change table PCT (R & B) is specified by index information from the reference accompaniment pattern memory AM (R & B), and the column is specified by the function name from the key note / function determination flow. For convenience, FIG. 8 illustrates the pitch after the change at the intersection of the row and the column. actually,
At each intersection, difference pitch data is stored in order to shorten the data length. The illustrated table PCT (R
Of the columns of & B), the column of BAS stores reference pitch data, and the columns of other function names store difference pitch data with respect to the reference pitch. When the BAS data is added to the difference pitch data, the changed pitch by the function name is obtained.

In FIG. 8, 1M represents a reference function name. G4 is written at the intersection of row r25 and column 1M,
G5 is written at the intersection of the row rt6 and the column 1M. This is because in the reference accompaniment pattern, the index information r25
And rt6 indicate that the pitch data is played as an accompaniment sound of the same pitch class G when the reference function name is used. Looking at column 37, row r25 shows B4 and row r
G5 is written at t6. This means that the sound played as the accompaniment sound of the same pitch class G at the time of the reference function name is 37.
When the function name is 3 (function is 3 and type is 7th), it means that one is played as a pitch class B and the other is played as a pitch class G accompaniment sound.

As described above, by using the index information, the accompaniment sound played at the same pitch (or pitch class) with respect to the reference function name (or tonality) can be compared with another function name (tonality). Can be played as accompaniment sounds of different pitches (pitch classes).

FIG. 9 shows a flowchart of the accompaniment process 4-5. First, in 9-1, the CPU 100 fetches the next pattern element AM _T [i] to be processed from the accompaniment pattern memory AM [] corresponding to the specified style. If the pattern element is a pitch element (Y in 9-2), the CPU
100 performs the 9-3, from the function name and the index information AM _T of the specified style and the current code [i], and look up the pitch change table PCT, reference pitch B
Obtain AS and difference pitch data. Next, (9-4), a difference pitch is added to the reference pitch BAS. As a result of this addition, when the key note is C and the designated style, a pitch P suitable for the current chord / function name is obtained. Further, the pitch P is transposed with the key note of the current chord, and the pitch data ANT of the actual accompaniment sound is calculated (9-5).

Finally (9-6), the CPU sends a note-on command including the actual pitch data ANT to the musical sound generation device 10.
8 to produce the accompaniment sound of the pitch ANT.

Although the embodiment has been described above, various modifications and changes can be made within the scope of the present invention. For example, the reference accompaniment pattern memory AM is stored in the pitch change table PCT.
The pitch (difference pitch) from the pitch for the reference tonality in [] may be stored, and the difference pitch looked up may be added to the pitch data from the reference accompaniment pattern memory during operation.

[0027]

As described above in detail, according to the present invention, the accompaniment pattern for only the reference tonality is stored in the reference accompaniment pattern storage means, and the accompaniment pitch is obtained in order to obtain an accompaniment pattern matching each tonality. A change means is provided, and in the accompaniment sound pitch change means, an accompaniment sound played at the same pitch or pitch class at the reference tonality is played as an accompaniment sound at a different pitch (pitch class) at another tonality. Since the means for changing the accompaniment pitch is provided, it is possible to realize a variety of accompaniments while suppressing the storage capacity.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of an automatic accompaniment device according to one embodiment of the present invention.

FIG. 2 is a hardware block diagram of the automatic accompaniment apparatus of the embodiment.

FIG. 3 is a main flowchart of the embodiment.

FIG. 4 is a flowchart of an interrupt routine.

FIG. 5 is a flowchart of a key note / function determination routine.

FIG. 6 is a flowchart of a style input process.

FIG. 7 is a diagram showing rhythm & blues accompaniment pattern data.

FIG. 8 is a diagram showing a pitch change table of rhythm & blues.

FIG. 9 is a flowchart of an accompaniment process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chord progression input device 2 Key / function determination part 4 Reference accompaniment pattern memory 5 Pitch change table memory 7 Adder 8 Transposition adder PP Pitch index 100 CPU 102 ROM 106 Input device

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G10H 1/38

Claims (1)

(57) [Claims] A chord progression providing means for providing a chord progression; a tonality determining means for analyzing the chord progression to determine a tonality of each chord; and an accompaniment formation for forming an accompaniment based on the determined tonality. In an automatic accompaniment apparatus comprising: an accompaniment forming means, a reference accompaniment pattern storage means for storing an accompaniment pattern for a reference tonality, and an accompaniment pattern for the determined tonality,
An accompaniment pitch changing means for changing each accompaniment pitch included in the accompaniment pattern read from the reference accompaniment pattern storage means, wherein the accompaniment pitch changing means has a different tonality from the reference tonality. In contrast, an automatic accompaniment apparatus including means for changing the accompaniment pitch so that the accompaniment pitch of the same pitch class included in the read accompaniment pattern becomes an accompaniment pitch of a different pitch class.