JP2005165119A - Automatic music composition apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily compose a naturally audible music which has a music length according with a user's desired time length without largely shifting a tempo of the music. <P>SOLUTION: A music progress template is adjusted in accordance with acquired prescribed standard tempo and standard musical time pattern and a set time length after being read out, and a music is automatically composed on the basis of the adjusted music progress template. In adjustment of the music progress template, partial measures in the music progress template are changed from the standard musical time pattern to a modified musical time pattern. Since the music can be composed per beat more finely than music per measure by changing partial measures of the music progress template from the standard musical time pattern to the modified musical time pattern to modify the music progress template itself, a music having a designated time length is easily composed without largely shifting the tempo of the music. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an automatic music apparatus that automatically generates music based on a music progression template for automatic music. In particular, by performing an automatic song based on a song progression template in which part of the information it has changed according to the specified time length, it is easy to have a natural audible song with a song length that matches the user's desired time length. The present invention relates to an automatic music composition apparatus that can generate a song.

2. Description of the Related Art Conventionally, there has been known an automatic music composition apparatus that automatically generates a music (for example, a melody) using a music progression template for automatic music prepared in advance (hereinafter simply referred to as a composition template). For example, in the automatic composition apparatus described in Patent Document 1 or Patent Document 2 shown below, which has already been filed by the present inventor, for composition that is similar to or similar to the composition conditions such as time length, tempo or time signature specified by the user One or a plurality of templates are presented to the user, and the user selects a desired composition template from the composition templates presented by the user, so that the automatic composition of the melody is performed based on the selected composition template. It has come to be. In this specification, the “composition template” is data that forms a melody template that defines various information necessary for generating a melody such as a melody structure, pitch pattern, and rhythm pattern for one song. For example, it has various information such as song composition information, each bar information, chord progression information, etc. in a hierarchical structure in the order of the whole music (block), music section, bar, etc. (described later) (See FIG. 3).
JP-A-11-119774 JP 2003-029749 A

  By the way, the composition templates prepared in advance have a predetermined length that can be generated, and the user can create a composition template for automatically generating a song having a song length that matches the specified time length. Although it must be selected, such a composition template required by the user is not always sufficiently prepared. Therefore, if there is no composition template that automatically generates a song with a song length that matches the specified time length, the user selects a song with a song length close to the specified time length from the presented candidates. The composition template for automatic generation can be selected. However, in such a case, the song generated based on the selected composition template is a song having a different song length that does not match the time length specified by the user as it is, so that the song is generated to fit the specified time length. You need to fine-tune the tempo of the song. Therefore, depending on the selected composition template, it is not possible to generate a song having a song length that matches the time length specified by the user unless the tempo is significantly shifted, but it is unnatural if the tempo is shifted too much. There was a problem that an audible song was generated, which was inconvenient. In addition, since the length of music that can be automatically generated is inevitably limited, it is not possible to easily generate music having various time lengths.

  The present invention has been made in view of the above points, and when a composition template that does not correspond to a specified time length is selected, a part of the bars are changed to a different time signature. It is an object of the present invention to provide an automatic song apparatus that can easily generate a song having a specified time length without greatly shifting the tempo of the song by automatically adjusting the composition template appropriately.

The automatic music composition apparatus according to the present invention includes a reading means for reading a music progression template, an acquisition means for acquiring a predetermined standard tempo and standard time signature, a time setting means for setting a time length of a music to be generated, and the acquired A music progress template adjusting means for adjusting the read music progress template according to a predetermined standard tempo and standard time signature and the set time length, and a generating means for automatically generating a music based on the adjusted music progress template With.
As a preferred embodiment of the present invention, the music progression template adjusting means adjusts the music progression template by changing some measures in the music progression template from a standard time signature to a variable time signature.

  According to the present invention, after the music progression template is read out, the music progression template is adjusted according to the acquired predetermined standard tempo and standard time signature and the set time length, and the music progression template is adjusted based on the adjusted music progression template. Is automatically generated. The adjustment of the song progression template is to change some measures in the song progression template from standard time signature to variable time signature. In this way, changing some of the measures in the song progress template from the standard time signature to the odd time signature and changing the song progress template itself allows the song to be generated in units of beats finer than the measure unit. It is possible to easily generate a song having a specified time length without greatly shifting the.

  The present invention may be constructed and implemented not only as an apparatus invention but also as a method invention. Further, the present invention can be implemented in the form of a program of a processor such as a computer or a DSP, or can be implemented in the form of a storage medium storing such a program.

  According to this invention, even when a music progression template (composition template) that does not correspond to the specified time length is selected, a part of the bars in the composition template is designated as an odd time signature. Since the composition template is adjusted appropriately according to the time and the automatic composition is performed, it is easy to make a natural audible song having a song length that matches the user's desired time length without greatly shifting the tempo of the song. The effect that it becomes possible to produce | generate is acquired.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram of a hardware configuration showing an embodiment of an automatic musical composition apparatus according to the present invention. The automatic musical composition apparatus shown in this embodiment is controlled by a microcomputer comprising a microprocessor unit (CPU) 1, a read only memory (ROM) 2, and a random access memory (RAM) 3. The CPU 1 controls the operation of the entire automatic music composition apparatus. For this CPU 1, ROM 2, RAM 3, communication interface (I / F) 4, input operation unit 5, display unit 6, external storage device 7, and sound source 8 are respectively connected via a communication bus 1D (for example, data and address bus). It is connected. Further, a timer (not shown) is connected to the CPU 1, and this timer generates a clock pulse necessary for setting a tempo used for automatically performing an automatically tuned music together with accompaniment. The clock pulse from the timer is given to the CPU 1 as a processing timing command or an interrupt command, and the CPU 1 executes various processes according to these commands.

  The ROM 2 stores various control programs to be executed or referred to by the CPU 1, various data, and the like. The RAM 3 is a working program that temporarily stores automatic performance information used when automatically playing the composed music, various data generated when the CPU 1 executes a predetermined control program, or a control program currently being executed. And a memory for storing data related thereto. A predetermined address area of the RAM 3 is assigned to each function and used as a register, flag, table, memory, or the like. The external interface (I / F) 4 is, for example, a communication interface for transmitting / receiving various control programs, various data, and the like between the automatic musical composition apparatus and the external device 4A. That is, the communication interface is connected to a wired or wireless communication network such as a LAN, the Internet, or a telephone line, and is connected to an external device 4A such as a personal computer or a server computer via the communication network. This is for fetching the various control programs, various data, etc. generated in the above to the automatic musical composition apparatus side.

  The input operation unit 5 is a switch or an operator for inputting various composition conditions used for automatic composition. Of course, in addition to these, the input operation unit 5 performs various operations such as a numeric keypad for inputting numeric data, a keyboard for inputting character data, and a pointing device (for example, a mouse) used for operating a predetermined pointer displayed on the display 6A. May contain children. The display unit 6 is a display 6A composed of, for example, a liquid crystal display panel (LCD), a CRT, or the like, and various kinds of information related to automatic composition such as composition conditions input by the user, composition templates and accompaniment style data presented to the user. Of course, automatic performance information relating to automatic performance, the control state of the CPU 1, and the like are also displayed.

  The external storage device 7 stores various control programs executed by the CPU 1 (for example, automatic composition processing described later), various data (for example, composition templates and accompaniment style data, or generated melody data and accompaniment data). When the control program is not stored in the ROM 2, the control program is stored in the external storage device 7 (for example, a hard disk), and is read into the RAM 3 to store the control program in the ROM 2. A similar operation can be performed by the CPU 1. In this way, control programs can be easily added and upgraded. The external storage device 7 is not limited to a hard disk (HD), but a flexible disk (FD), a compact disk (CD-ROM / CD-RAM), a magneto-optical disk (MO), a DVD (Digital Versatile Disk), etc. It may be a storage device that uses various external recording media. Alternatively, a semiconductor memory or the like may be used.

  The tone generator 8 can simultaneously generate music signals on a plurality of channels, and inputs various performance information such as melody data and accompaniment data given via the communication bus 1D, and based on these performance information, Is generated. A musical sound signal generated from the sound source 8 is generated from a sound system 8A including an amplifier and a speaker. A predetermined effect may be applied to the musical sound signal generated from the sound source 8 using an effect circuit or the like (not shown). The format of the melody data or accompaniment data may be digitally encoded such as MIDI format, or may be composed of a waveform sample data system such as PCM, DPCM, or ADPCM. Any conventional configuration may be used for the configuration of the sound source 8 and the sound system 8A. For example, the sound source 8 may employ any of various tone synthesis methods such as FM, PCM, physical model, formant synthesis, etc., or may be constituted by dedicated hardware, or by software processing by the CPU 1. Also good.

  Note that the above-described automatic musical composition device is not limited to one in which the input operation unit 5, the display 6A, the sound source 8, and the like are built in one device body, but each is configured separately and uses communication means such as various interfaces and various networks. Needless to say, each device may be configured to be connected. Furthermore, the apparatus to which the automatic musical composition apparatus according to the present invention is applied is applicable to any type of apparatus / equipment such as an electronic musical instrument, a personal computer, a portable communication terminal such as a PDA or a mobile phone, or a karaoke apparatus or a game apparatus. May be.

  Next, “automatic music processing” in which the music is automatically set according to the composition conditions set by the user will be described with reference to FIGS. FIG. 2 is a flowchart showing an example of “automatic music processing”. FIG. 3 is a conceptual diagram showing a data structure of a composition template before and after a part is changed based on the above “automatic composition process”. The upper part of FIG. 3 conceptually shows the data structure of the composition template before the change, and the lower part of FIG. 3 conceptually shows the data structure of the composition template after the change. In the composition template after change shown in the lower part of FIG. 3, the changed part is hatched. In order to make the explanation easier to understand, when the standard tempo is a quarter note = 118 and the standard time signature is 4/4 (4/4) time, from the 6th measure 24 beats shown in the upper part of FIG. An operation of generating a song with a time length of 11 seconds using a composition template will be described as a specific example.

In step S1, various parameters are set for music generation. That is, in accordance with the setting input from the input operation unit 5 by the user, the composition condition required for the automatic composition using the composition template is set. Composition conditions set and input by the user include, for example, genres (8 beats, classical, etc.), key (major / minor), melodic (flowing melody) / rhythmic (engraved melody), and songs to be generated Length (time length). In addition, an accompaniment style for generating an accompaniment attached to the automatically composed music is also set as a composition condition. In step S2, the corresponding accompaniment style data is acquired from the external storage device 7 (style database) according to the set accompaniment style, and the standard tempo defined in the acquired accompaniment style data (for example, quarter note = 118). ) And the time length (for example, 11 seconds) set as the composition condition, the number of beats of the entire song to be generated is calculated. The number of beats of the entire song is calculated by the following formula 1. However, since the number of beats must be an integer in a music piece, in this embodiment, when the calculated required number of beats is a decimal, the decimal part is rounded off to make the necessary number of beats an integer.
(Equation 1)
Required beats = specified time / (60 / standard tempo)
Therefore, when the standard tempo is a quarter note = 118, the number of beats required for the entire song having a time length of 11 seconds is 22 (11 / (60/118) = 21.63, rounded to 22).

  In step S3, the standard time signature defined in the accompaniment style data read in step S2 and the required number of beats calculated according to the above equation 1 are used to calculate the standard time signature and the variable time measure. Ask. That is, when the number of beats (necessary number of beats) of the entire music is divided into a bar composed of standard time signatures and a bar composed of variable time signatures, the number of bars required for each is obtained. For example, when the standard time signature is 4/4 time, when calculating the number of bars of standard time and the number of bars of variable time required to generate a song consisting of 22 beats, it is a multiple of 4. The closest number of beats exceeding the required number of beats of 22 is 24, which corresponds to 6 bars of a bar composed of 4/4 time signatures. Therefore, in this case, one bar (2 beats) is required as a bar composed of 5 bars (20 beats) and 2 beats as a bar composed of standard time signatures. When obtaining the number of measures of the standard time signature and the number of measures of the variable time signature, four measures (16 beats) are defined as the measures composed of the standard time signature, and three measures are defined as the measures composed of the two beats. It may be divided as appropriate, such as a set segment (6 beats), etc., but use as many bars as possible with standard time signatures so as not to cause loss of musical hearing due to heavy use of variable time signatures. It is good to make it.

  In step S4, the number of measures of the standard time signature and the number of measures of the variable time signature obtained in step S3 are added, and a composition template corresponding to the corresponding number of measures is selected from the external storage device 7 or the like to select the RAM 3 or the like. Read in. At this time, if there are multiple composition templates that correspond to the number of measures of the entire song obtained by adding the number of measures of the standard time signature and the number of measures of the variable time signature, the corresponding composition template is selected as a candidate. It may be presented to the user and appropriately selected from the candidates presented by the user. In this way, a composition template corresponding to the six bars shown in the upper part of FIG. 3 is read out as a composition template used for the automatic composition.

  In step S5, it is automatically determined to which position in the music the measure of odd time signature is assigned. For example, in the composition template, the beginning and end of the song and the beginning and end of the block are avoided, and the measure to be randomly selected from other measures is determined. Such automatic determination is executed by an algorithm, for example. In the example of FIG. 3, an odd time signature is assigned to the second measure. In step S6, the passage information (section type) affected by the introduction of an odd time signature is corrected. In other words, if there are other passage types in the song that include measures that have been changed to variable time signatures, the melody will change when the time signature is changed. However, it is needless to say that when the odd time signature is assigned to the same part of the same type of passage, it is not necessary to change the type of the passage. In the example of FIG. 3, the second measure included in the first passage “a” is changed to an odd time signature. The section type “c” is different from the section type “a”. If the passage type of the passage including the measure changed to the variable time is present before the relevant passage, the passage type of the passage including the measure changed to the variable time is corrected.

  In step S7, the chord progression information of the measure of odd time signature is adjusted. As an example of a rule for adjusting this chord progression information, for example, when the number of chords is the same, only the length of each chord is changed, and when the number of chords is large, 2, 3, 1, There are a number of rules such as deleting from chords at 4 beats, and adding from chords at 4, 1, 2, 3 of the original chord when the number of chords is small. In the example of FIG. 3, the number of chords is “G7” and “C”, which is the same as before the change, so the length of each chord is changed by changing from 2 beats to 1 beat. The chord progression information of the measure of the time signature has been adjusted.

  According to the above processing, when a song having a time length of 11 seconds is generated using a song template composed of 24 beats of six measures shown in the upper part of FIG. 3, the song template shown in the lower part of FIG. 3 is newly generated. That is, the entire bar is composed of 6 bars of 6 bars of 5 bars (20 beats) and 2 bars of 1 bar (2 beats) as a bar composed of standard beats, A composition template having a measure composed of variable time signatures having two time signatures in the second measure is generated. In step S8, melody data is created based on the newly generated composition template. That is, a song (melody) is automatically generated using a newly generated composition template. In step S9, accompaniment data is created based on the accompaniment style data and chord progression information acquired in step S2.

In step S10, tempo adjustment is performed as necessary. In step S11, the melody data and the accompaniment data generated according to the adjusted tempo and the like are reproduced to execute an automatic performance of the melody and the accompaniment. Here, the tempo adjustment will be briefly described. If the playback time (music length) of the song at the current tempo is different from the specified time, it is possible to adjust the playback time of the song to the specified time by adjusting the tempo by the following method. For example, there are a method by manual input by the user and a method for automatically detecting a tempo that is closest to a specified time. As an example of the automatic detection method, the correction tempo is determined using the following equation (2).
(Equation 2)
Corrected tempo = (required beats * 60) / generation time Note that if the corrected tempo adjusted by any of the above-mentioned methods greatly deviates from the standard tempo, resulting in a musically unnatural sensation. It is better to process the last tempo of the song. For example, if it takes a long time at the current tempo, a ritardando process may be added to the end of the song, or fermata or fade-out may be applied to keep it within the time.

  As shown in the above-described embodiment, when the tempo adjustment is performed by replacing a part of the composition template with an odd time signature, the deviation from the standard tempo can be reduced as compared with the conventional case. That is, in this embodiment, the correction tempo is 120 ((22 * 60) / 11). On the other hand, when the tempo is corrected conventionally, the corrected tempo is 131 ((24 * 60) / 11). As can be understood from the above, the correction tempo 120 in this embodiment is less shifted from the standard tempo 118 than the conventional correction tempo 131. Therefore, in the automatic musical composition apparatus according to the present invention, it is possible to easily generate a musical piece having a musical piece length corresponding to the designated time at a tempo close to the standard tempo.

The composition template includes various pieces of information such as song composition information, each bar information, and chord progression information as shown in FIG. 3, but is not limited to this. For example, chord progression information is stored in a separate file. The chord progression information may be obtained by referring to the file from the composition template.
Note that the standard tempo used as a reference may be the one included in the composition template, or the standard tempo of the selected accompaniment style data may be read and used. Or what the user specified may be used.

If there is no composition template that corresponds to the number of measures for the entire song, select a composition template that corresponds to the nearest number of measures that is greater than the required number of beats, It is also possible to obtain the required number of beats by deleting the beat of the measure (the measure becomes a measure composed of variable time signatures). Alternatively, a composition template corresponding to the nearest number of measures that is smaller than the required number of beats may be selected and read out, and the required number of beats may be obtained by adding the number of beats to some measures. Further, a measure template composed of variable time signatures may be prepared in advance, and the variable time measure template may be replaced with a measure to which a variable time signature is to be assigned.
At the end of the composition, a new template name may be assigned to the newly created composition template after the change and stored in the external storage device 7 or the like. Alternatively, the newly created composition template after change may be automatically deleted at the end of the composition.

1 is a hardware configuration block diagram showing an embodiment of an automatic music composition apparatus according to the present invention. It is a flowchart which shows one Example of an automatic music composition process. It is a conceptual diagram which shows the data structure of the template for composition before and after a part is changed based on an automatic composition process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... CPU, 2 ... ROM, 3 ... RAM, 4 ... Communication interface, 4A ... External device, 5 ... Input operation part, 6 ... Display part, 6A ... Display, 7 ... External storage device, 8 ... Sound source, 8A ... Sound System, 1D ... communication bus

Claims (3)

Reading means for reading the song progression template;
Obtaining means for obtaining a predetermined standard tempo and standard time signature;
A time setting means for setting the time length of the song to be generated;
Song progression template adjustment means for adjusting the read song progression template according to the acquired predetermined standard tempo and standard time signature and the set time length;
A self-composing music apparatus comprising generating means for automatically generating music based on the adjusted music progression template.   The automatic music composition apparatus according to claim 1, wherein the music progression template adjusting means adjusts the music progression template by changing a part of bars in the music progression template from a standard time signature to a variable time signature.   The correction means for correcting the acquired predetermined standard tempo is provided, and a music automatically generated based on a music progression template according to the corrected tempo can be reproduced. Automatic music composition device.

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