The present invention relates generally to techniques for automatically musically arranging music performance information and more particularly to a technique capable of making a simple automatic arrangement (musical arrangement), capable of being performed by a human player with ease, without losing musical quality of an original music piece.
Japanese Patent Application Laid-open Publication No. 2005-202204 (hereinafter referred to as “Patent Literature 1”) discloses a technique in which a user selects a desired part (musical part) from MIDI-format automatic performance data of a plurality of parts of a given music piece and a musical score of a desired format is created for the user-selected part. According to a specific example disclosed in Patent Literature 1, the user selects a melody part, accompaniment data suitable for a melody of the selected melody part are automatically created, and then a musical score comprising the selected melody part and an accompaniment part based on the automatically-created accompaniment data is created. More specifically, Patent Literature 1 discloses a method for automatically creating accompaniment data suitable for a melody, in which a plurality of accompaniment patterns corresponding to different performance levels are prepared in advance, one of the accompaniment patterns that corresponds to a performance level selected by the user is selected, and accompaniment data are automatically created on the basis of the selected accompaniment pattern and with a chord progression in the melody taken into consideration.
With the prior technique disclosed in Patent Literature 1, however, it is not possible to make musical arrangements, such as changing tone generation timings of individual accompaniment tones based on the user-selected accompaniment pattern, deleting any of the accompaniment tones, and/or adding one or more new accompaniment tones. Further, with the technique disclosed in Patent Literature 1, the accompaniment patterns prepared in advance for selection by the user have no direct relation with an original music piece of a melody or the like, to which accompaniment tones based on the accompaniment pattern are to be added, and thus, depending on the accompaniment pattern selection by the user, an accompaniment pattern having a poor musical compatibility with an original music piece, such as a melody, may sometimes be undesirably used.
In view of the foregoing prior art problems, it is an object of the present invention to provide an automatic arrangement apparatus and method which extract performance information of an accompaniment part from an original music piece and automatically arrange the extracted performance information of the accompaniment part.
In order to accomplish the above-mentioned object, the present invention provides an improved automatic arrangement apparatus, which comprises a processor configured to: acquire original performance information; extract, from the acquired original performance information, performance information of one or more accompaniment parts as accompaniment part performance information; and create arranged accompaniment part performance information by using, in accordance with a predetermined arrangement condition, only any one or more of pitch names included in the extracted accompaniment part performance information.
According to the present invention, performance information of one or more accompaniment parts is extracted as accompaniment part performance information, and arranged accompaniment part performance information is created using only any one or more of pitch names included in the extracted accompaniment part performance information. Thus, the present invention can create accompaniment part performance information having a good compatibility with the original music piece (original performance information) and also can automatically make such an arrangement as to shift an accompaniment note included in the accompaniment part performance information or increase or reduce the number of accompaniment notes included in the accompaniment part performance information.
In an embodiment of the present invention, the processor is further configured to identify a chord progression in the acquired original performance information. The predetermined arranging condition comprises instructing that any of chord component notes be thinned out in the identified chord progression, and the processor is configured to create the arranged accompaniment part performance information by thinning out, from among accompaniment notes in the extracted accompaniment part performance information, an accompaniment note of a pitch name corresponding to the chord component note having been instructed to be thinned out by the predetermined arranging condition. Thus, in a case where the original music piece (original performance information) has a complicated chord progression, for example, the present invention can automatically make such an arrangement as to create simple accompaniment part performance information, so that it can readily make an automatic arrangement capable of being performed with ease by a beginner human player.
In an embodiment of the present invention, the predetermined arranging condition comprises setting a ratio between chords and arpeggios in one or more measures. Here, the processor is configured to create the arranged accompaniment part performance information by changing a combination of chords and arpeggios in the extracted accompaniment part performance information so that a ratio between chords and arpeggios in one or more measures in the extracted accompaniment part performance information assumes the set ratio. In this way, the present invention can automatically make such an unprecedented arrangement as to change as desired a ratio between chords and arpeggios in one or more measures.
The automatic arrangement apparatus of the present invention may be constructed of a dedicated apparatus or circuitry configured to perform necessary functions, or by a combination of program modules configured to perform their respective functions and a processor (e.g., a general-purpose processor like a CPU, or a dedicated processor like a DSP) capable of executing the program modules.
The present invention may be constructed and implemented not only as the apparatus invention discussed above but also as a computer-implemented method invention comprising steps of performing various functions. Also, the present invention may be constructed and implemented as a program comprising a group of instructions executable by a processor for performing the method, as well as a non-transitory computer-readable storage medium storing such a program.
The following will describe embodiments of the present invention, but it should be appreciated that the present invention is not limited to the described embodiments and various modifications of the invention are possible without departing from the basic principles. The scope of the present invention is therefore to be determined solely by the appended claims.
Certain preferred embodiments of the present invention will hereinafter be described in detail, by way of example only, with reference to the accompanying drawings, in which:
In block 21, chord information is acquired which is indicative of a chord progression of the music piece in the acquired original performance information. If any chord information is contained in the acquired original performance information, that chord information may be acquired. If no chord information is contained in the acquired original performance information, on the other hand, a chord may be detected by analyzing a melody or accompaniment progression, contained in the acquired original performance information, using a conventionally-known chord analysis technique, and then chord information may be acquired on the basis of the chord detection. Alternatively, a user may input chord information via the input device 4 or the like, and chord information may be acquired on the basis of the user's input. In subsequent generation of harmony-creating accompaniment data, the thus-acquired chord information is used for shifting pitches of accompaniment notes indicated by the accompaniment data.
In blocks 22 and 23, a melody part (if any) and one or more accompaniment parts are separated and extracted from the acquired original performance information, to acquire original performance information of the melody part (block 22) and original performance information of each of the one or more accompaniment parts (accompaniment part performance information) (block 23). Note that, if the original performance information acquired in block 20 contains part information or identification information similar to the part information, part-specific original performance information may be acquired by use of such part information or identification information. Further, in the case where the original performance information comprises a musical score image and if the musical score comprises a melody score (G or treble clef score) and accompaniment score (F or bass cleft score) as in a piano score or if the musical score comprises part-specific musical staff notations, part-specific original performance information can be acquired on the basis of such a score. If the musical score does not comprise part-specific musical staff notations, notes of individual parts, such as a melody part, chord part and bass part, may be extracted presumptively through analysis of the musical score. When the CPU 1 performs the process of block 23, it functions as a means for extracting, from the acquired original performance information, performance information of one or more accompaniment parts as accompaniment part performance information.
In block 24, arranged accompaniment part performance information is created by arranging a particular accompaniment part, extracted in block 23 above, by using, in accordance with a predetermined arranging condition, any one or more of pitch names included in the accompaniment part performance information of the particular accompaniment part. In the illustrated example of
The rule as to how chord component notes to be thinned out should be determined can be defined as appropriate. For example, where the original accompaniment part performance information instructs simultaneously sounding three or more chord component notes, the rule may define that a tension note of the three or more chord component notes be thinned out.
As another example, where the original accompaniment part performance information instructs simultaneously sounding three or more chord component notes, the rule may be defined so as to thin out one of notes of a same pitch name but of different octaves (i.e., notes having a same pitch name but belonging to different octaves) in three or more chord component notes.
Note that the rule as to how chord component notes to be thinned out should be determined may be defined, for example, taking into consideration of any one, or a combination of, (1) degrees of dissonance among individual chord component notes in each chord, (2) level of difficulty of performance, (3) degrees of dissonance of individual chord component notes with a melody, etc. Generally, it is considered that, if an arrangement is made involving a low degree of dissonance and low level of difficulty of performance, then the arrangement can be one relatively suitable and natural. Regarding the (1) degrees of dissonance of notes, chord component notes basically have low degrees of dissonance, while a tension note has a high degree of dissonance. Further, the level of dissonance may differ between different chord component notes or between different tension notes. Regarding the (2) level of difficulty of performance, consideration is made, for example, of ease of performing the chord (e.g., a manner of placement of chord component notes) itself, degree of variation in the number of notes (normally, the level of difficulty increases as the variation in the number of notes increases in frequency), degree of necessary fingering movement, etc. Regarding the (3) degrees of dissonance of individual chord component notes with a melody, consideration is made, for example, of conflict of the individual chord component notes with the melody and conflict in sounding pitch range (e.g., octave) between the individual chord component notes and the melody; note that the degrees of dissonance among the individual chord component notes within each chord is determined in the (1) item above. More specifically, regarding the (3) item, where a chord component note of pitch name “D” and a melody note of pitch name “C” are of a same octave, for example, generated tones would undesirably give a dull feeling because the two notes are too close to each other in pitch; thus, in this case, the chord component note (“D”) is thinned out. Regarding the (1) item, on the other hand, a chord component note is thinned out even where the chord component note is of a different sounding pitch range (octave) from a melody note if the chord component note and the melody note are in dissonant relationship; for example, where a chord component note of pitch name “D” and a melody note of pitch name “C” are of different octaves, the chord component note is thinned out because the two notes are in dissonant relationship.
Referring now back to
Further,
The process of block 24a is similar to the process of block 24 in that arranged accompaniment part performance information is created by arranging a particular accompaniment part, extracted in block 23 above, by using, in accordance with the predetermined arranging condition, any one or more of pitch names included in accompaniment part performance information of the particular accompaniment part, but different in specific construction from the process of block 24. Namely, an accompaniment including chords and arpeggios is extracted as a single accompaniment part in block 23. Then, in block 24a, where the predetermined arranging condition comprises setting a ratio between chords and arpeggios (i.e., chord vs. arpeggio ratio) in one or more measures, the arranged accompaniment part performance information is created by changing a combination of chords and arpeggios in accompaniment part performance information of the extracted accompaniment part, including chords and arpeggios, in such a manner that a ratio between the chords and arpeggios in the accompaniment part performance information in the one or more measures assumes the set ratio. The ratio between chords and arpeggios (chord vs. arpeggio ratio) in the one or more measures may be set at a value desired by the user.
Further, as to how a chord should be broken down and converted into an arpeggio, an appropriate rule may be defined such that the chord is converted into an arpeggio in accordance with such a rule. Typically, a note value of each note constituting such a converted-to arpeggio (i.e., arpeggio (component) note) may be determined with the rhythm of the music piece in question taken into consideration. For example, an arpeggio of eighth notes is suitable for an eight-beat music piece, and an arpeggio of sixteenth notes is suitable for a sixteenth-beat music piece. It is generally known that triplet timings have a good compatibility with swing and shuffle music pieces. The rhythm of the music piece in question may be obtained by reference to a setting by the user or genre of the music piece, by detection through analysis of the original performance information, and the like.
Alternatively, various types of arpeggio patterns may be registered in advance for each of various different chord types (such various types of arpeggio patterns to be registered in advance may be set by the user) so that a particular arpeggio pattern corresponding to the type of the chord to be converted into an arpeggio can be selected from among the pre-registered various types of arpeggio patterns and the chord can be converted into an arpeggio in accordance with the selected arpeggio pattern.
Further, in a case where a chord is to be converted into an arpeggio, a manner of determining a series of arpeggio notes (arpeggio component notes) may be differentiated between a time when the percentage of arpeggios (arpeggio percentage) in the above-mentioned chord vs. arpeggio ratio is high and a time when the percentage of arpeggios in the chord vs. arpeggio ratio is low. An arpeggio pattern differing depending on the arpeggio percentage in the chord vs. arpeggio ratio may be used. Namely, if the arpeggio percentage is 80% through 100%, an arpeggio pattern with a series of arpeggio notes covering one measure may be used, or if the arpeggio percentage is 40% through 20%, an arpeggio pattern with a series of arpeggio notes covering one beat may be used. Furthermore, in a case where a plurality of chords are present in a measure, a particular rule may be applied for determining which of the chords in the measure should be converted into an arpeggio. Conceivable examples of such a rule include, among other things, one for preferentially converting chords at the fourth and second beats into arpeggios, one for randomly determining a chord to be converted into an arpeggio, and one for, by reference to a melody (right hand part), preferentially converting into an arpeggio a chord at a position where sounding (tone generation) of a melody note is extended (i.e., the melody note is sustained with a relatively long note value). If an accompaniment is performed in an arpeggio at a position where sounding of a melody note is extended or sustained as noted above, it is conceivable that the user can effectively concentrate on an arpeggio performance with his or her left hand but also can give an appropriate rhythm feel, so that a musical arrangement effective and easy to perform can be achieved.
Furthermore, an appropriate rule may also be defined as to how a series of arpeggio notes should be converted into a chord, so that a series of arpeggio notes can be converted into a chord in accordance with such a rule. Typically, it is assumed here that, in principle, all notes constituting an arpeggio are simultaneously converted into a chord so that they are sounded simultaneously just as in the illustrated example of
This application is based on, and claims priority to, JP PA 2015-185300 filed on 18 Sep. 2015. The disclosure of the priority application, in its entirety, including the drawings, claims, and the specification thereof, are incorporated herein by reference.
Number | Date | Country | Kind |
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2015-185300 | Sep 2015 | JP | national |
Number | Date | Country | |
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Parent | 15262594 | Sep 2016 | US |
Child | 16120885 | US |