JP2016057389A - Chord determination device and chord determination program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chord determination device capable of deciding chords by estimating pitch names of unknown constitution sounds when the pitch names of the constitution sounds of a portion of the chords (chord) are unknown.SOLUTION: An electronic musical instrument 10 stores a plurality of chord information showing a combination of constituting sounds of various chords respectively. The electronic musical instrument 10 compares pitch information acquired within a performance zone immediately before the current performance progress position and the chord information, and decides the sound names of the plurality of constituting sounds including the at least fundamental notes among the constituting sounds which constitute the chords in the performance zone immediately after the current performance progress point based on the most maximum adaptable chord information. The electronic musical instrument 10 generates distribution information DB showing a distribution of the kind of the music sounds emitted in the performance zone prior to the current performance progress position. The electronic musical instrument 10 estimates the sound names of the undecided constituting sounds so as to decide the chords based on the decided constituting sounds and the distribution information DB when the fundamental notes are decided and either one of the names among the sound names of the third and fifth sounds is undecided.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a code determination device and a code determination program for acquiring pitch information representing a pitch and determining a chord based on the acquired pitch information.

  Conventionally, for example, as described in Patent Documents 1 and 2 and Non-Patent Document 1 below, electronic musical instruments having an automatic accompaniment function are known. These electronic musical instruments store a plurality of accompaniment pattern data respectively representing a plurality of types of accompaniment patterns. When the performer selects one accompaniment pattern data and performs it using the keyboard device, the electronic musical instrument controller uses the pitch information (note number) of the musical sound generated in the immediately preceding performance section to perform the next performance. Determine the section code. Then, the control unit of the electronic musical instrument reproduces the accompaniment pattern by correcting the accompaniment pattern data so as to match the determined chord.

Japanese Patent No. 2629564 Japanese Patent No. 2616258

Yamaha Corporation, “YAMAHA Clavinova CVP-609 / CVP-605 Instruction Manual”, February 2014, p. 45-53

  According to the automatic accompaniment function of the electronic musical instrument described in Non-Patent Document 1, when only the root of the chord and the fifth sound are determined (that is, when the third sound is not determined), The accompaniment pattern is reproduced by correcting the third sound to the root sound or the fifth sound. Therefore, the accompaniment pattern to be reproduced may be monotonous as compared with the case where the root tone, the third tone, and the fifth tone are determined.

  The electronic musical instrument of Non-Patent Document 1 has a function of displaying the determined code name on the screen. Depending on the music, a certain chord is assumed, but there is a phrase (score) that uses only part of the chord (for example, the root and the fifth). In this case, the electronic musical instrument of Non-Patent Document 1 cannot determine the chord because part of the constituent sound (for example, the third sound) of the chord is unknown, but represents the pitch name of the part of the constituent sound that can be determined. Display information on the screen. For example, when only the root tone and the fifth tone can be determined and the pitch name of the root tone is “C”, “C1 + 5” is displayed. However, such a notation is not generally used as a code name.

  Also, the performer needs to press the key at an appropriate timing so that the intended chord is determined. This operation is difficult for beginners or performers who lack knowledge about chords.

  The present invention has been made to cope with the above-described problem, and its purpose is to estimate the pitch names of the unknown constituent sounds when the pitch names of some of the constituent sounds of the chord (chord) are unknown. Thus, it is an object of the present invention to provide a code determination device capable of determining a code. In addition, in the description of each constituent element of the present invention below, in order to facilitate understanding of the present invention, reference numerals of corresponding portions of the embodiment are described in parentheses, but each constituent element of the present invention is The present invention should not be construed as being limited to the configurations of the corresponding portions indicated by the reference numerals of the embodiments.

  In order to achieve the above object, the present invention is characterized by pitch information acquisition means (S13) that sequentially acquires pitch information representing the pitch of a musical tone, and pitch information storage that stores the acquired pitch information. Acquired in the means (BF, S14), the chord information storage means (12b) storing a plurality of chord information representing combinations of various chords, and the performance section (SC1) immediately before the current performance progress position. The pitch information and the chord information are compared, and at least the root of the constituent sounds constituting the chord of the performance section (SC2) immediately after the current performance progress position is based on the chord information having the highest fitness. Component sound determining means (S19) for determining the names of a plurality of component sounds including sounds, and distribution information (DB) representing the distribution of types of musical sounds generated in the performance section before the current performance progress position Distribution information generation means (S17) for generating the chord, and when the pitch names of the chord root, the third sound, and the fifth sound are determined, the chord is determined based on the determined component sound, When a root sound is determined and one of the third and fifth sound names is undecided, the component sound is determined based on the component sound determined by the component sound determination means and the distribution information. The present invention is to provide a chord determination device including chord determination means (S23, S24) for estimating the pitch names of undecided constituent sounds and determining the chord.

  In this case, the distribution information generating means counts the number of musical sounds generated in the section before the current performance progress position for each musical name, and calculates the count value for each musical name. The chord determination means outputs the pitch names of the constituent sounds that have not been determined, and the pitch names of the constituent sounds that have a count value in the distribution information that exceed a predetermined threshold. It is preferable to use a code determination device that estimates that.

  Further, in this case, the chord determination means is the current performance progress position of a plurality of pitch name candidates that are pitch names of the undetermined constituent sounds whose mutual pitches are short degrees. It is preferable that the chord determination apparatus estimates one of the constituent sound candidates as a pitch name of the constituent sound of the chord based on the appearance status in the previous section.

  Further, in this case, the distribution information generating means counts the number of pronunciations of the musical sound produced in the section before the current performance progress position for each musical name, and count value for each musical name. Is output as the distribution information, and the chord determining means is a case where the fifth sound has not been determined, and the pitch between the root sound and the other constituent sounds determined by the constituent sound determining means is Unlike perfect 4 degrees, the count value of the pitch name whose pitch between the root sounds in the distribution information is complete 5 degrees exceeds a predetermined threshold, and between the root sounds in the distribution information The count value of the pitch name whose pitch is reduced by 5 degrees is “0”, and the pitch between each musical sound generated in the performance section immediately before the current performance progress position and the root tone is long. If it is different from 6 degrees and 6 degrees short, Pitch is estimated that the note name of the fifth sound note name is perfect fifth between may be code determination device.

  According to the chord determination device configured as described above, even if the pitch name of either the third sound or the fifth sound is unknown, the pitch name of the unknown component sound is estimated using the distribution information. can do. Therefore, it is possible to suppress the reproduced accompaniment pattern from becoming monotonous. Further, when the pitch names of the determined chords or the constituent sounds of the chord are displayed on the screen, the number of performance sections in which only the pitch names of the constituent sounds of a part of the chord are displayed can be reduced. Also, the performer does not need to perform with care so that all the constituent sounds of the chord are included in each performance section. Therefore, even a beginner or a player who has little knowledge about chords can enjoy playing using the automatic accompaniment function.

  Note that the present invention is not limited to implementation as a code determination device, but can also be implemented as a computer program (code determination program) applied to a computer included in the code determination device.

It is a block diagram which shows the structure of the electronic musical instrument to which the chord determination apparatus which concerns on one Embodiment of this invention was applied. It is a functional block diagram of the electronic musical instrument of FIG. It is a flowchart which shows the first half part of a code determination program. It is a flowchart which shows the second half part of a code determination program. It is a conceptual diagram which shows an example of each performance area and distribution information. It is a conceptual diagram which shows the structure of a counter.

  An electronic musical instrument 10 according to an embodiment of the present invention will be described. First, an outline of the electronic musical instrument 10 will be described. The electronic musical instrument 10 stores a plurality of accompaniment pattern data respectively representing a plurality of types of accompaniment patterns. When the performer selects one accompaniment pattern and performs using the keyboard device, the electronic musical instrument 10 determines the chord of the next performance section. The next performance section is a section immediately after the current performance progress position. The length corresponds to a half-beat length in the playback tempo (set by the user) of the accompaniment pattern. For example, when the playback tempo (set by the user) of the accompaniment pattern is 120 BPM, the length of the next performance section is 250 msec. If the chord cannot be determined because the pitch names of some of the constituent sounds of the chord (for example, the third or fifth sound) are unknown, the electronic musical instrument 10 estimates the pitch names of the unknown constituent sounds The code can then be determined. Then, the electronic musical instrument 10 corrects the accompaniment pattern data so as to match the determined chord, and reproduces the accompaniment pattern.

  Next, a specific configuration of the electronic musical instrument 10 will be described. As shown in FIG. 1, the electronic musical instrument 10 includes an input operator 11, a computer unit 12, a display 13, a storage device 14, an external interface circuit 15, a sound source circuit 16, and a sound system 17, which are bus BUS. Connected through.

  The input operator 11 includes a switch corresponding to an on / off operation, a volume or rotary encoder corresponding to a rotation operation, a volume or linear encoder corresponding to a slide operation, a mouse, a touch panel, and the like. Further, the input operator 11 includes a keyboard device used when playing music. The input operator 11 also includes a pedal operator (damper pedal). The input operator 11 is used when setting various parameters, playing music, and the like. For example, it is used when selecting one of a plurality of accompaniment pattern data, setting the playback tempo of the selected accompaniment pattern, or instructing the start / stop of automatic accompaniment. When the performer operates the input operator 11, operation information indicating the operation content is supplied to the computer unit 12 described later via the bus BUS. For example, when a performer presses a key on a keyboard device, pitch information indicating the pitch of the key is supplied to the computer unit 12.

  The computer unit 12 includes a CPU 12a, a ROM 12b, a RAM 12c, and a timer 12d connected to the bus BUS. The CPU 12a reads various programs from the ROM 12b and executes them. For example, when the CPU 12a executes a predetermined program, the electronic musical instrument 10 functions as an automatic accompaniment device AA as shown in FIG. The automatic accompaniment apparatus AA includes a chord determination unit CD that determines the chord of the next performance section, and an accompaniment pattern playback unit PR that corrects the accompaniment pattern data to match the determined chord and reproduces the accompaniment pattern. . That is, when the CPU 12a executes a predetermined program, the electronic musical instrument 10 functions as the chord determination unit CD and the accompaniment pattern reproduction unit PR. In addition to the various programs, the ROM 12b stores initial setting parameters, graphic data for generating display data representing an image displayed on the display 13, character data, and the like. The ROM 12b stores a plurality of pieces of chord information each representing a combination of pitch names of various chords. Various data are temporarily stored in the RAM 12c when various programs are executed. The timer 12d starts counting at the start of automatic accompaniment. The count value represents the current performance progress position.

  The display 13 is configured by a liquid crystal display (LCD). The computer unit 12 generates display data representing contents to be displayed using graphic data, character data, and the like, and supplies the display data to the display unit 13. The display device 13 displays an image based on the display data supplied from the computer unit 12. For example, when performing using the automatic accompaniment function, the name of the chord at the current performance progress position, the pitch name of the constituent sound of the chord, and the like are displayed.

  The storage device 14 is composed of a large-capacity nonvolatile recording medium such as an HDD or a DVD and a drive unit corresponding to each recording medium.

  The external interface circuit 15 includes a connection terminal that allows the electronic musical instrument 10 to be connected to an external device such as another electronic musical instrument or a personal computer. The electronic musical instrument 10 can be connected to a communication network such as a LAN (Local Area Network) or the Internet via the external interface circuit 15.

  The waveform memory WM stores a plurality of timbre waveform data representing the acoustic waveforms of musical sounds such as piano, organ, violin, trumpet and the like. The tone generator circuit 16 reads out the timbre waveform data designated by the CPU 12 a from the waveform memory WM, generates a digital sound signal, and supplies the digital sound signal to the sound system 17.

  The sound system 17 includes a D / A converter that converts a digital sound signal into an analog sound signal, an amplifier that amplifies the converted analog sound signal, and a left and right pair that converts the amplified analog sound signal into an acoustic signal and outputs the sound signal. The speaker is provided. Note that the sound system 17 may include an effect circuit that imparts effects such as reverb and chorus to various musical sounds.

  Next, the operation of the code determination unit CD will be described. When the performer selects one accompaniment pattern and sets its playback tempo to start playback of the accompaniment pattern, the CPU 12a reads the chord determination program shown in FIGS. 3A and 3B from the ROM 12b and executes it. Thereby, the computer unit 12 functions as the code determination unit CD. The CPU 12a reads an accompaniment pattern reproduction program (not shown) from the ROM 12b and executes it in parallel with the chord determination program. Thereby, the computer unit 12 and the sound source circuit 16 function as an accompaniment pattern reproducing unit PR. Hereinafter, the operation of the code determination unit CD will be described.

  In step S10, the code determination unit CD starts code determination processing. Next, the code determination unit CD executes an initialization process in step S11. For example, the chord determination unit CD secures a buffer BF for storing pitch information (“C3”, “D # 3”, “B4”, etc.) supplied from the keyboard device in the RAM 12c. In addition, for example, the value of the write pointer indicating one address in the buffer BF is set as the head address of the buffer BF. Next, the code determination unit CD starts the timer 12d in step S12. Next, the chord determination unit CD determines whether or not pitch information is supplied from the keyboard device in step S13. If the pitch information is supplied, the chord determination unit CD determines “Yes” and stores the pitch information in the buffer BF in step S14. Specifically, the pitch information is written to the address indicated by the write pointer, and the write pointer is incremented. Then, the code determining unit CD proceeds with the process to step S15. As will be described later, since a series of processes including steps S13 and S14 is repeatedly executed, the pitch information sequentially supplied from the keyboard device to the chord determination unit CD is stored in the buffer BF in the order in which they are supplied. Is done. On the other hand, if the pitch information is not supplied from the keyboard device, the chord determination unit CD determines “No” and proceeds to step S15.

Next, in step S15, the chord determination unit CD uses the count value of the timer 12d to determine whether or not the current performance progress position is on the bar line (corresponds to the first beat of each bar). Or not). For example, if the automatic accompaniment tempo is set to 120 BPM and the selected accompaniment style is 4/4 time, the length of one bar is 2 seconds. Therefore, in this case, when the value of the timer 12d matches 2 × n seconds (n is a natural number), the chord determination unit CD determines that the current performance progress position is on the bar line. When the current performance progress position is on the bar line, the chord determination unit CD determines “Yes”, and in step S16, the bar pointer information B _n (see FIG. 4) indicating the bar line is written. Write to the address pointed to and increment the write pointer. The subscript “n” of the bar line information _Bn represents the number of bar lines counted from the beginning of the performance. Next, in step S17, the code determination unit CD generates and stores a distribution information DB described below. Specifically, the chord determination unit CD selects pitch information written between the bar line information _Bn written this time and the bar line information _Bn-2 written previously. The number of the selected pitch information is counted for each pitch name and stored as a distribution information DB. The distribution information DB generated in this way represents the distribution of pitch names of musical sounds produced in the two-measure section immediately before the measure including the current performance progress position. Note that the count values of all pitch names in the distribution information DB are set to “0” in the section of two measures immediately after the performance is started (that is, the first two measures).

  On the other hand, in step S15, when the current performance progress position is at a position different from the bar line, the chord determination unit CD determines “No” and proceeds to step S18.

  Next, the chord determination unit CD determines whether or not the current performance progress position is located at the front beat or the back beat in step S18. If the current performance progress position is located at the front beat or the back beat, the chord determination unit CD determines “Yes” and proceeds to step S19. In step S19, the chord determination unit CD plays the tone of the musical sound generated in the performance section SC1 immediately before the current performance progress position (the section from the current performance progress position to a position retroactive by a half-beat length). Based on the name (that is, pitch information acquired in the performance section SC1), the chord (chord) of the next performance section SC2 is determined. Similar to the conventional electronic musical instrument, the chord determination unit CD compares the combination of musical note names generated in the performance section SC1 with the various chord information stored in the ROM 12b, and provides the best fit. Based on the high chord information, the pitch names of a plurality of constituent sounds including at least the root note of the chord are determined. However, when the number of key presses (pitch information) in the performance section SC1 is small, it is possible to determine only the root name and the fifth note name among the constituent sounds of the chord, and the third note name is determined. There are things that cannot be done. In addition, only the root name and the third note name can be determined, and the fifth note name cannot be determined. In such a case, the chord of the performance section SC2 cannot be determined. Therefore, the code determination unit CD determines in step S20 whether or not the code has been determined by the process of step S19.

  If the code can be determined, the code determination unit CD determines “Yes” and proceeds to step S23 described later. If the chord cannot be determined, the chord determination unit CD determines “No” and cannot determine the chord in step S21 based on the appearance status (distribution) of each pitch name in the performance section SC0. The third or fifth note name is estimated, and the chord is determined. For example, if the pitch name of the third sound cannot be determined, the chord determination unit CD refers to the distribution information DB, and the pitch between the determined root sound is 3 degrees long and 3 degrees short. The count values of the pitch names are compared, and the pitch name with the larger count value is selected. If the count value of the selected pitch name exceeds a predetermined threshold (eg, “3”), the pitch name is estimated as the pitch name of the third pitch of the chord.

  Also, for example, if the pitch name of the fifth note cannot be determined, and the following four conditions are all satisfied, the chord determination unit CD has a complete pitch of 5 degrees with the determined root note. Is assumed as the fifth note name. The first condition is that the pitch between the root tone and the other constituent sounds among the determined constituent sounds is completely different from 4 degrees. The second condition is that, in the distribution information DB, the count value of the pitch name whose pitch between the determined root note is completely 5 degrees exceeds a predetermined threshold (for example, “3”). The third condition is that in the distribution information DB, the count value of the pitch name whose pitch between the determined root note is 5 degrees is “0”. The fourth condition is that the pitch between each musical tone sounded in the immediately preceding performance section SC1 and the determined root tone is different from the long 6 degrees and the short 6 degrees.

  For example, if two component sounds are determined, the pitch name of the root tone is “G”, and the pitch name of the other component sound is “B”, the first to fourth conditions If all are satisfied, the pitch name of the fifth sound is estimated to be “D”. That is, in this case, the chord of the next performance section is determined to be “G major”.

  On the other hand, when two constituent sounds are determined, the root name is “C”, and the other constituent name is “F” (semitone higher than 3 degrees) State (sus4)), the first condition is not satisfied. In this case, if the first condition is ignored and the pitch name of the fifth sound is “G”, the chord is “Csus4”. However, even though “C” of the two determined sounds is determined to be a root sound, in reality, “F” is a root sound and “C” is a fifth sound. there is a possibility. That is, the actual code may be “F major” or “F minor”. If the actual chord is “F major” or “F minor” and the chord is determined to be “Csus4”, the sound may become muddy. Therefore, the above first condition is provided.

  Also, for example, when two constituent sounds are determined, the root name is “E”, and the other constituent name is “G”, the fourth condition is satisfied. If it is ignored and the pitch name of the fifth sound is “B”, the chord becomes “E minor”. However, even though “E” of the two determined sounds is determined to be a root sound, actually “C” is a root sound and “E” is a third sound. there is a possibility. That is, the actual code may be “C major”. If the actual chord is “C major” and the chord is determined to be “E minor”, “B” of the determined sounds of “E minor” and the actual chord “C” are determined. The pitch between “C”, which is the root of “Major”, is 6 degrees short, and the sound may be murky. In addition, when “C #” is included in the note name of the musical sound generated in the immediately preceding performance section SC1, “C #” may be included in the next performance section SC2. Since the pitch between “C #” and “B” among the determined sounds of “E minor” is 6 degrees long, there is a possibility that the sound may be murky. Therefore, the above fourth condition is provided.

  Next, the code determination unit CD determines in step S22 whether or not the code has been determined by the process of step S21. If the chord can be determined, the chord determining unit CD determines “Yes”, and supplies chord information representing the determined chord to the accompaniment pattern reproducing unit PR and the display unit 13 in step S23, The process proceeds to step S13. On the other hand, if the chord cannot be determined, the chord determination unit CD determines “No”, and in step S24, the pitch name information indicating the pitch names of the determined root sound and other constituent sounds is obtained. The accompaniment pattern reproducing unit PR and the display unit 13 are supplied, and the process proceeds to step S13.

  Thereafter, the code determination unit CD repeatedly executes the process consisting of steps S13 to S24. Thereby, chord information or pitch name information is supplied to the accompaniment pattern reproducing unit PR at a predetermined time interval (length of eighth note). The accompaniment pattern reproduction unit PR modifies the accompaniment pattern data according to the supplied chord information or pitch name information, and reproduces the accompaniment pattern. The accompaniment pattern is played back in a loop. In other words, when the end of the accompaniment pattern is reached, it is played again from the beginning. However, when the reproduction of the accompaniment pattern of the last scene (ending section) of the music is completed, or when the performer instructs to end the reproduction of the accompaniment pattern using the input operator 11, the automatic accompaniment apparatus AA Then, the chord detection and the accompaniment pattern reproduction are finished.

  When the display unit 13 acquires the code information from the code determination unit CD, the display unit 13 displays the name of the code. Further, when the display unit 13 acquires the pitch name information from the chord determination unit CD, in addition to the pitch name of the root tone, the display unit 13 displays the pitch between the determined root tone and the determined component sounds as a number. Display (for example, “C1 + 5”).

  According to the electronic musical instrument 10 (the chord determination unit CD) configured as described above, even if the pitch name of either the third sound or the fifth sound is unknown, the unknown information can be obtained using the distribution information DB. The pitch names of the constituent sounds can be estimated. That is, the number of performance sections in which chords are not determined can be reduced as compared with the conventional art. Therefore, it is possible to suppress the reproduced accompaniment pattern from becoming monotonous. In addition, the number of performance sections in which only the pitch names of part of the chord are displayed on the display 13 can be reduced. Also, the performer does not need to perform with care so that all the constituent sounds of the chord are included in each performance section. Therefore, even a beginner or a player who has little knowledge about chords can enjoy playing using the automatic accompaniment function.

  Furthermore, in carrying out the present invention, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the object of the present invention.

  For example, in the above embodiment, the performance section SC0 of the two measures immediately before the measure including the current performance progress position is set as the distribution information DB generation target. However, the length of the performance section SC0 that is a generation target of the distribution information DB is not limited to this, and may be, for example, a length of one measure or a length of three measures. In the above embodiment, the distribution information DB of the performance section SC0 of the two measures immediately before the measure is used regardless of the position in the measure at which the chord constituent sound is estimated. For example, the chord constituent sound is estimated at the second beat of the sixth measure and the chord constituent sound is estimated at the third beat of the sixth measure. A distribution information DB representing the distribution of pitch names of musical sounds generated in the performance section up to the end of the fifth measure is used. However, instead of this, the performance section to be generated in the distribution information DB may be changed according to the position of the timing for estimating the constituent sound of the chord within the measure. For example, if the chord component is estimated at the 2nd beat of the 6th measure, the note name of the musical tone that is pronounced in the performance section from the beginning of the 2nd beat of the 4th measure to the end of the 1st beat of the 6th measure It is also possible to generate a distribution information DB representing the distribution of and to use the distribution information DB. In this case, when the current performance progress position is located at the front beat or the back beat, the beat information representing the beat position is written in the buffer BF, and this beat information is used as a performance to be generated in the distribution information DB. What is necessary is just to specify an area.

  Further, the distribution information DB may be updated when the code is determined. For example, if the root name of the constituent sounds of the chord and the pitch name of the fifth sound are determined and the pitch name of the third sound is unknown, the chord determination unit CD determines the determined root sound in the performance section SC0. The distribution information DB may be generated by counting the pitch names having a pitch of 3 degrees and 3 degrees as follows. The chord determination unit CD searches for pitch names having a pitch of 3 degrees long and 3 degrees short from the determined root note toward the end of the performance section SC0. As shown in FIG. 5, the chord determination unit CD increments the count value of the first counter CT1 every time a pitch name having a pitch of 3 degrees with the determined root tone is searched. In addition, the count value of the second counter CT2 is incremented each time a pitch name whose pitch between the determined root note is 3 degrees short is searched. However, when the count value of one counter is incremented after the count value of one counter is incremented, the count value of the one counter is cleared (set to “0”). A pitch name in which the pitch between the above-mentioned root position and the determined root value when the search position reaches the end of the section to be generated in the distribution information DB is 3 degrees long and 3 degrees short Is stored as a count value. Note that the chord determination unit CD searches for pitch names having a pitch of 3 degrees long and 3 degrees short from the end of the section to be generated in the distribution information DB from the end to the head. The count value of the counter may be incremented each time a pitch name that is the same as the first pitch name searched is searched. Then, when the other pitch name is searched, the counting process is terminated. When the count value of the one pitch name exceeds a predetermined threshold (for example, “3”), the one pitch name is changed. You may estimate with the pitch name of a 3rd sound. According to this, the pitch name of the third sound can be determined in consideration of the transition between the major scale and the minor scale.

  In the above embodiment, when the current performance progress position is located at the front beat or the back beat, the combination of the pitch name of the musical sound generated in the performance section SC1 immediately before the current performance progress position and the chord information, Based on the matching, the pitch names of the constituent sounds of the chord are determined. The length of the performance section SC1 corresponds to the length of an eighth note. However, the length of the performance section SC1 is not limited to the above embodiment. For example, the length of the performance section SC1 may be set to the length of a sixteenth note. In this case, the chord may be determined with a time interval of the length of a sixteenth note.

  Further, the length of the performance section SC1 referred to determine the chord may be set slightly longer than the time interval for determining the chord. For example, the length of the performance section SC1 may be made longer by the length of the 32nd note than the time interval for determining the chord. Also, the chord is re-determined by adding the tone name of the musical tone sounded within the short interval (for example, the 48th note length interval) once the chord has been determined, to the tone name of the component sound of the determined chord. You may do it. According to this, even when the key is pressed slightly earlier than the timing for determining the chord or when the key is pressed slightly later, the pitch information related to the key press is reflected in the determination of the chord. Can do. The time interval for determining the chord and the length of the performance section SC1 referred to for determining the chord may be changeable.

  Further, for example, not only the pitch information but also the key pressing strength (velocity) and key pressing length (duration) may be acquired as key pressing information from the keyboard device and stored in the buffer BF. Then, the distribution information DB may be generated in consideration of the acquired key pressing strength and key pressing length. For example, key pressing information whose key pressing strength is smaller than a predetermined threshold (for example, less than 5% of the maximum value) may be ignored. Further, key pressing information whose key pressing length is shorter than a predetermined threshold (for example, the length of a 64th note) may be ignored. When the damper pedal is depressed, even if the key is released, it may be considered that the key pressing is continued. In this case, when the damper pedal is released, the key pressing length may be detected (calculated).

  In the above embodiment, the chord determination unit CD stores all pitch information acquired from the keyboard device in the buffer BF, but stores only pitch information necessary for generating the distribution information DB. Then, pitch information that is no longer necessary may be deleted sequentially. For example, pitch information three bars or more before the bar including the current performance progress position may be sequentially deleted.

  Moreover, in the said embodiment, although the chord determination part CD acquires the pitch information from a keyboard apparatus, you may acquire pitch information from an external apparatus. Further, the electronic musical instrument 10 may have a function of reproducing sequence data representing a pitch information series. In this case, the chord determination unit CD may acquire the reproduced pitch information. The code determination unit CD acquires audio data representing an acoustic waveform from an external device, the storage device 14, and the like, analyzes the acquired audio data to generate pitch information, and uses the generated pitch information. You may decide the code.

  In addition, when the pitch name of the fifth sound is unknown, the electronic musical instrument 10 can be operated between the operation mode operating as in the above embodiment and the determined root sound without considering the above four conditions. You may be comprised so that either one of the modes which estimate the pitch name which becomes a pitch completely 5 degree | times as a 5th sound can be selected.

  Further, the chord determination unit CD may determine a chord using only pitch information included in a low pitch range (for example, a pitch range lower than “C4”) among pitch information acquired from the keyboard device. .

  If the chord determination unit CD fails to determine the chord, the chord information representing the chord of the previous performance section may be supplied to the accompaniment pattern reproduction unit PR. Further, if the chord determination unit CD fails to determine the chord, only the performance part of the percussion instrument may be reproduced by the accompaniment pattern reproduction unit PR.

  Further, when the root name of the chord and the pitch name of the fifth sound are determined, and the pitch name of the third sound is unknown, the pitch between the determined root sound is long in the distribution information DB. When the count values of the pitch names that are the second and the third minor are both “1” or more, the chord determination unit CD may not estimate the pitch name of the third sound. In addition, when the difference between the count values of pitch names having a pitch of 3 degrees and 3 degrees with respect to the determined root note is equal to or greater than a predetermined threshold value, the pitch name with the larger count value is selected as the chord name. You may estimate with the pitch name of a 3rd sound.

  In addition, for example, when the root note and the third note of the chord are determined and the note name of the fifth note is unknown, it is not determined whether the four conditions in the above embodiment are satisfied, The pitch name of the fifth sound may be determined based on the count value of the distribution information DB. In this case, for example, the number of pronunciations of each pitch name may be counted using a counter similar to the counter shown in FIG. Specifically, counters corresponding to the pitch names at which the pitch between the root note is 5 degrees, 5 degrees and 5 degrees are provided. In the performance section SC0, every time a pitch name whose pitch between the root note is decreased by 5 degrees, complete 5 degrees and increased 5 degrees is searched, the counter corresponding to the searched pitch name is counted. While incrementing the value, the count values of other counters are cleared. When the count value of one of these three counters exceeds a predetermined threshold, the pitch name corresponding to the counter may be estimated as the pitch name of the fifth tone.

  If only the root note (1st and 8th) of the chord is determined and the pitch names of the third and fifth notes are unknown, the chord determining unit CD performs the fifth procedure in the same procedure as in the above embodiment. The pitch name may be estimated, and the root name and the pitch name information indicating the estimated pitch name of the fifth sound may be supplied to the accompaniment pattern reproducing unit PR and the display unit 13. In this case, the chord determination unit CD may determine the chord by estimating the pitch name of the fifth sound and the pitch name of the third sound in the same procedure as in the above embodiment.

DESCRIPTION OF SYMBOLS 10 ... Electronic musical instrument, 11 ... Input operation element, 12 ... Computer part, 13 ... Display, 14 ... Memory | storage device, 16 ... Sound source circuit, 17 ... Sound system, AA ... automatic accompaniment device, BF ... buffer, _Bn ... bar line information, CD ... code determination unit, CT1, CT2 ... counter, DB ... distribution information, PR ... Accompaniment pattern playback unit, SC0 to SC2 ... performance section, WM ... waveform memory

Claims (5)

Pitch information acquisition means for sequentially acquiring pitch information representing the pitch of a musical tone;
Pitch information storage means for storing the acquired pitch information;
A chord information storage means for storing a plurality of chord information each representing a combination of constituent sounds of various chords;
The pitch information acquired in the performance section immediately before the current performance progress position is compared with the chord information, and the chord of the performance section immediately after the current performance progress position is based on the chord information having the highest degree of fitness. Component sound determination means for determining the pitch names of a plurality of component sounds including at least the root sound of the component sounds constituting
A distribution information generating means for generating distribution information representing a distribution of types of musical sounds generated in a performance section before the current performance progress position;
When the root names of the chord, the third sound, and the fifth sound are determined, the chord is determined based on the determined constituent sounds, the root sound is determined, and the third sound is determined. And when one of the pitch names of the fifth sound is undetermined, the pitch name of the undetermined component sound is estimated based on the component sound determined by the component sound determining means and the distribution information. A code determination device comprising code determination means for determining the code. The code determination device according to claim 1,
The distribution information generation means counts the number of musical sounds generated in the section before the current performance progress position for each musical name, and uses the count value for each musical name as the distribution information. Output,
The chord determination means estimates the pitch name of the constituent sound that is not yet determined and whose count value in the distribution information exceeds a predetermined threshold as the pitch name of the constituent sound of the chord apparatus. The code determination device according to claim 2,
The chord determination means is a section of a plurality of pitch name candidates whose pitches are not yet determined, and that are prior to the current performance progress position. A chord determination apparatus that estimates one of the constituent sound candidates as a pitch name of a constituent sound of a chord based on the appearance status in FIG. The code determination device according to claim 3,
The chord determining means is a case where the fifth sound is undecided, and the pitch between the root sound determined by the constituent sound determining means and the other constituent sounds is different from perfect 4 degrees, A sound whose pitch value between the root notes in the distribution information is completely 5 degrees exceeds a predetermined threshold value, and a pitch between the root sounds in the distribution information is a decrease of 5 degrees The pitch between the musical sound and the root tone that are pronounced in the performance section immediately before the current performance progress position is 6 degrees long and 6 degrees short when the name count value is “0” A chord determination apparatus that estimates a pitch name whose pitch between the root note is completely 5 degrees as a pitch name of the fifth tone when they are different. A computer program applied to a code determination device for determining a code, comprising: a computer provided in the code determination device;
Pitch information acquisition means for sequentially acquiring pitch information representing the pitch of a musical tone;
Pitch information storage means for storing the acquired pitch information;
A chord information storage means for storing a plurality of chord information respectively representing combinations of various chord constituent sounds;
The pitch information acquired in the performance section immediately before the current performance progress position is compared with the chord information, and the chord of the performance section immediately after the current performance progress position is based on the chord information having the highest degree of fitness. Component sound determination means for determining the pitch names of a plurality of component sounds including at least the root sound of the component sounds constituting
Distribution information generating means for outputting distribution information representing the distribution of types of musical sounds generated in the performance section before the current performance progress position;
When the root names of the chord, the third sound, and the fifth sound are determined, the chord is determined based on the determined constituent sounds, the root sound is determined, and the third sound is determined. And when one of the pitch names of the fifth sound is undetermined, the pitch name of the undetermined component sound is estimated based on the component sound determined by the component sound determining means and the distribution information. A computer program that functions as code determining means for determining the code.

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