JP5703693B2 - Code detection apparatus and program - Google Patents

Description

  The present invention relates to a chord detection system that can perform chord detection on a free performance such as playing both hands by a user.

  Conventionally, an electronic music apparatus having a function of detecting a chord by a performance operation is known. For example, in the automatic accompaniment device disclosed in Patent Document 1, a user performance sound is searched for at the chord detection timing, matching with a pre-stored chord pattern is performed, and if there are only two keys pressed, a fractional chord is obtained. One of the specified two sounds is regarded as a root, and a fractional code is determined based on a predetermined rule, and automatic accompaniment based on the determined code is performed.

Japanese Patent No. 2526430

  However, in the conventional chord detection technique, chords are detected when chord constituent sounds are arranged by the user's performance. Therefore, the user must press the chord constituent sounds with the keyboard accurately at the detection timing. Since it is necessary to press the key so that it becomes the chord you want to detect, it is not suitable for free performances such as playing both hands. In addition, in order for a chord to be detected, it is necessary for the user's performance sound to include a sound that is the root of the chord.

  In view of such circumstances, the present invention provides a chord detection system capable of detecting an appropriate chord having a route that has not been played even if the performance sound of the user performance or the like does not include a sound corresponding to the route. The purpose is to provide.

  According to the first feature of the present invention, a plurality of notes [root (r), third degree (3), fifth degree (5), fourth voice ( 4), Altered system (a), Tension note (t), Avoid note, etc.) points indicating musical importance are set, and every chord (DegreeName) is a point for the role of root (r) Point table storage means (4) storing a point table (PT) set to a low value, performance data acquisition means (5; P12-P13) for acquiring performance data, and key information for acquiring key information (Key) Acquisition means (P15), code detection instruction (P14 = YES), code detection instruction means (P2, P14), and code detection instruction means (P2, P14) at a predetermined code detection timing (T1-T3: P2) ) (P14 = YES), the key information acquired by the key information acquisition means (P15) (K14) ey) based on candidate code extraction means (P16) that extracts candidate codes (ChordList: each candidate code is represented by DegreeName) and when code detection is instructed by the code detection instruction means (P2, P14) (P14 = YES), pitch information (NoteList: Note) that is considered valid at the chord detection timing (T1-T3: P2) is extracted from the performance data acquired by the performance data acquisition means (5; P12-P13) When pitch detection is instructed by the pitch information extraction means [P13 (N1-N6), P17 (C5)] and the code detection instruction means (P2, P14) (P14 = YES), the candidate code extraction means ( For each candidate code (DegreeName) extracted by P16), each pitch information (Note) extracted by the pitch information extraction means [P13 (N1-N6), P17 (C5)] Which note of the notes (root (r), 3rd (3), 5th (5), 4th voice (4), alter (a), tension note (t), void note, etc.) Note role discrimination means [P17 (C6 = FIG. 10, FIG. 11)] for discriminating whether or not it is detected and when chord detection is instructed by the chord detection instruction means (P2, P14) (P14 = YES) All pitch information (NoteList: Note) extracted by the pitch information extracting means [P13 (N1-N6), P17 (C5)] is routed by means [P17 (C6 = FIG. 10, FIG. 11)] Code detection means [P17 (C11-C16)] for detecting an optimum code (Chord) from candidate codes determined to have a role (3, 5, 4, ...) other than r), For each candidate code (DegreeName) extracted by the code extraction means (P16), the point corresponding to the role determined by the note role determination means [P17 (C6 = FIG. 10, FIG. 11)] is obtained from the point table (PT). Extracted and summed (C11), and the candidate code with the highest sum (point) is determined as the optimal code (Chord) (C16) [P17 (C11-C16)] code A plurality of notes (root (r), 3 degrees (3), 5 degrees (5), 4th voice (characters) characterizing the code (DegreeName) for each of the output device (Claim 1) and the possible code (DegreeName)) 4), Altered system (a), Tension note (t), Avoid note, etc.) points indicating musical importance are set, and every chord (DegreeName) is a point for the role of root (r) A performance data acquisition step (P12-P13) for acquiring performance data in a computer having a point table storage means (4) for storing a point table (PT) set at a low value and functioning as a chord detection device; A key information acquisition step (P15) for acquiring information (Key), and a code detection instruction step (P2, P14) instructing code detection at a predetermined code detection timing (T1-T3: P2) (P14 = YES) In the code detection instruction step (P2, P14), code detection is instructed. (P14 = YES), a candidate code extraction step for extracting a candidate code (ChordList: each candidate code is represented by DegreeName) based on the key information (Key) acquired in the key information acquisition step (P15) (P16) and when chord detection is instructed in the chord detection instruction step (P2, P14) (P14 = YES), the chord detection timing (from the performance data acquired in the performance data acquisition step (P12-P13) ( Pitch information extraction step [P13 (N1-N6), P17 (C5)] for extracting pitch information (NoteList: Note) regarded as valid for (T1-T3: P2), and chord detection instruction step (P2, P14) ) (P14 = YES), the pitch information extraction step [P13 (N1-N6), P17 () for each candidate code (DegreeName) extracted in the candidate code extraction step (P16). Each pitch information (Note) extracted in [C5)] includes a plurality of notes [root (r), 3 degrees (3), 5 degrees (5), 4th voice (4), alter] Note role determination step [P17 (C6 = FIG. 10, FIG. 11)] for determining which of the notes of the system (a), tension note (t), and void note, etc.) and chord detection instruction step (P2 , P14) when chord detection is instructed (P14 = YES), in the note role discrimination step [P17 (C6 = FIG. 10, FIG. 11)], the pitch information extraction step [P13 (N1-N6), P17 (C5)] all the pitch information (NoteList: Note) extracted from the candidate codes determined to have a role (3,5,4, ...) other than root (r) Chord) is a chord detection step [P17 (C11-C16)], and for each candidate code (DegreeName) extracted in the candidate chord extraction step (P16), a note role discrimination step [P17 (C6 = FIG. , Fig. 11)] is extracted from the point table (PT), and the points corresponding to the roles identified in [11]] are summed (C11), and the summed points (total points) are the highest value. A code detection program (Claim 3) for executing a procedure consisting of [C17] and [P17 (C11-C16)] is provided. Note that the parentheses indicate reference symbols, terms, parts, and the like of the examples added for convenience of understanding, and the same applies to the following.

  According to the second feature of the present invention, a plurality of notes [root (r), third degree (3), fifth degree (5), fourth voice ( (4) Point table storage means for storing a point table (PT) in which points indicating musical importance are set for the roles of (alternate system (a), tension note (t), void note, etc.) (4) Performance data acquisition means for acquiring performance data (5; P12-P13), key information acquisition means for acquiring key information (Key) (P15), and predetermined chord detection timing (T1-T3: P2) Code detection instruction means (P14 = YES), and when code detection is instructed by the code detection instruction means (P2, P14) (P14 = YES), key information acquisition means Extract the candidate code (ChordList: each candidate code is represented by DegreeName) based on the key information (Key) acquired by (P15) Performance data acquired by the performance data acquisition means (5; P12-P13) when the chord detection is instructed by the candidate chord extraction means (P16) and the chord detection instruction means (P2, P14) (P14 = YES) Pitch information extraction means [P13 (N1-N6), P17 (C5)] that extract pitch information (NoteList: Note) that is considered valid at the chord detection timing (T1-T3: P2), and chord detection When chord detection is instructed by the instructing means (P2, P14) (P14 = YES), for each candidate code (DegreeName) extracted by the candidate code extracting means (P16), the pitch information extracting means [P13 (N1 -N6), P17 (C5)], each pitch information (Note) is composed of a plurality of notes [root (r), 3 degrees (3), 5 degrees (5), 4th voice ( 4), note role discriminating means [P17 (C6 <FIG. 10, FIG. 11>, C7)] for discriminating which of the notes of the alter system (a), tension note (t), void note, etc.) , Code detection instruction hand When the chord detection is instructed by the stage (P2, P14) (P14 = YES), in the note role discrimination means [P17 (C6 <FIG. 10, FIG. 11>, C7)], the pitch information extraction means [P13 ( N1-N6), P17 (C5)] all the pitch information (NoteList: Note) extracted as candidate codes (3, 5, 4, ...) other than root (r) ChordList: DegreeName) is code detection means [P17 (C8-C16)] for detecting the optimum code (Chord), and for each candidate code (DegreeName) extracted by the candidate code extraction means (P16), Points corresponding to roles (3, 5, 4,...) Other than the route (r) determined by the note role determining means [P17 (C6 <FIG. 10, FIG. 11>, C7)] are obtained from the point table (PT). Extracted and summed (C11), and the candidate code with the highest sum (point) is determined to be the optimal code (Chord) (C16) with [P17 (C8-C16)] A code detector (claim 2); and For each possible chord (DegreeName), multiple notes that characterize the chord (DegreeName) [Root (r), 3rd (3), 5th (5), 4th voice (4), Altered system (a), Tension Point table storage means (4) storing a point table (PT) in which points indicating musical importance are set for the role of (note (t), void note, etc.), and functions as a chord detection device In the computer, a performance data acquisition step (P12-P13) for acquiring performance data, a key information acquisition step (P15) for acquiring key information (Key), and a predetermined chord detection timing (T1-T3: P2) Instructing code detection (P14 = YES) When code detection is instructed in the code detection instruction steps (P2, P14) and code detection instruction steps (P2, P14) (P14 = YES), the key information acquisition step ( Candidate codes (ChordList: individual candidate codes) based on the key information (Key) acquired in P15) When the chord detection is instructed in the chord detection instruction step (P2, P14) (P14 = YES), the performance data acquisition step (P12-P13) ) To extract pitch information (NoteList: Note) that is considered to be valid at the chord detection timing (T1-T3: P2) from the performance data acquired in step (P13 (N1-N6), P17 ( C5)] and when chord detection is instructed in the chord detection instruction step (P2, P14) (P14 = YES), the pitch of each candidate chord (DegreeName) extracted in the candidate chord extraction step (P16) Each pitch information (Note) extracted in the information extraction step [P13 (N1-N6), P17 (C5)] is a plurality of notes [root (r), 3 degrees (3), 5 degrees ( 5), 4th voice (4), Altered system (a), Tension note (t), Avoid note, etc.) [P17 (C6 <FIG. 10, FIG. 11>, C7)] and when chord detection is instructed in the chord detection instruction step (P2, P14) (P14 = YES), the note role discrimination step [P17 ( C6 <Fig. 10, Fig. 11>, C7)], all the pitch information (NoteList: Note) extracted in the pitch information extraction step [P13 (N1-N6), P17 (C5)] is the root (r ) In the code detection step [P17 (C8-C16)] for detecting the optimum code (Chord) from the candidate codes (ChordList: DegreeName) determined to have a role (3, 5, 4, ...) other than) For each candidate code (DegreeName) extracted in the candidate code extraction step (P16), except for the route (r) determined in the note role determination step [P17 (C6 <FIG. 10, FIG. 11>, C7)] The points corresponding to the roles (3,5,4, ...) are extracted from the point table (PT) and summed (C11), and the candidate code with the highest sum (point) is the optimal code (Cord) (C16) [P17 (C8 -C16)] is provided. A code detection program (Claim 4) is provided.

  In the chord detection system according to the first feature of the present invention (Claims 1 and 3), a plurality of notes characterizing a chord (DegreeName) for each chord (DegreeName) that can be a candidate [root (r), three degrees (3), 5th degree (5), 4th voice (4), Altered system (a), Tension note (t), Avoid note, etc.) The points indicating musical importance are set, and which chord (DegreeName) Also, a point table (PT) in which points for the role of the route (r) are set low is prepared in the point table storage means (4). For chord detection, for example, chord detection timing, that is, chord detection timing (T1-T3) is set with reference to a predetermined music timing such as every predetermined measure or every predetermined beat (6; P2) , Acquire performance data based on performance operations (key presses) such as playing both hands (5; P11-P12), acquire key information (Key) (P15), and at the set chord detection timing (T1-T3) When code detection is instructed (P14 = YES), the following processing is performed. First, candidate codes (ChordList: each candidate code is represented by DegreeName) are extracted based on the acquired key information (Key) (P16), and the chord detection timing (T1-T3) is effective from the acquired performance data. Pitch information (NoteList: Note) that is considered to be extracted [P13 (N1-N6), P17 (C5)]. Next, for each extracted candidate code (DegreeName), each pitch information (Note) includes a plurality of notes (root (r), third degree (3), fifth degree (5), fourth voice (4 ), Altered system (a), Tension note (t), Avoid note, etc.] is determined [P17 (C6 = FIG. 10, FIG. 11)]. Then, for each candidate code (DegreeName), the points corresponding to the determined roles are extracted from the point table (PT) and summed (C11), and the candidate code whose summed point (total points) is the highest value is selected. Candidate that all pitch information (NoteList: Note) is determined to have “role other than root (r) (3,5,4, ...)” by determining the optimal chord (Cord) (C16) The optimal code (Chord) is detected from the codes [P17 (C11-C16)]. Furthermore, automatic accompaniment data can be generated based on the detected chord (P18).

  Therefore, according to the present invention, even if a performance sound by a user performance or the like does not include a sound corresponding to the root, it is possible to detect an appropriate chord having a route that has not been performed, and the user can play both hands, etc. You can get an automatic accompaniment with appropriate chords while devoting yourself to free performance. Moreover, it is possible to easily detect a chord having a route that has not been played simply by adjusting the settings relating to the route in the point table.

  In the chord detection system according to the second feature of the present invention (claims 2 and 4), a plurality of notes characterizing the chord (DegreeName) for each chord (DegreeName) that can be a candidate [root (r), three degrees (3), Point table (PT) with points indicating musical importance for the roles of 5th degree (5), 4th voice (4), Altered system (a), Tension note (t), Avoid note, etc.) Is prepared in the point table storage means (4). For chord detection, for example, chord detection timing, that is, chord detection timing (T1-T3) is set with reference to a predetermined music timing such as every predetermined measure or every predetermined beat (6; P2) , Acquire performance data based on performance operations (key presses) such as playing both hands (5; P11-P12), acquire key information (Key) (P15), and at the set chord detection timing (T1-T3) When code detection is instructed (P14 = YES), the following processing is performed. First, candidate codes (ChordList: each candidate code is represented by DegreeName) are extracted based on the acquired key information (Key) (P16), and the chord detection timing (T1-T3) is effective from the acquired performance data. Pitch information (NoteList: Note) that is considered to be extracted [P13 (N1-N6), P17 (C5)]. Next, for each extracted candidate code (DegreeName), each pitch information (Note) includes a plurality of notes (root (r), third degree (3), fifth degree (5), fourth voice (4 ), Altered system (a), Tension note (t), Avoid note, etc.] is determined [P17 (C6 <FIG. 10, FIG. 11>, C7)]. Then, for each candidate code (DegreeName), the points corresponding to the roles (3, 5, 4, ...) other than the determined route (r) are extracted from the point table (PT) and summed (C11). By determining the candidate chord with the highest value (total points) as the best chord (Cord) (C16), all pitch information (NoteList: Note) will be assigned to a role other than root (r) ( The optimum code (Chord) is detected from the candidate codes determined to have “3, 5, 4,...” ”[P17 (C8-C16)]. Furthermore, automatic accompaniment data can be generated based on the detected chord (P18).

  In other words, [P17 (C6 <Fig.10, Fig.11>, C7)], each pitch information (Note) extracted by the pitch information extraction function (C5) is not root (r) (C7) and all pitch information (NoteList: Note) is “Roles other than root (r) (3,5,4,…) ”(C7 = NO), the code detection function [P17 (C8-C16)] determines the role other than“ root (r) (3) for each candidate code (DegreeName). , 5,4, ...) "is extracted from the point table (PT) and summed (C11), and the candidate code with the highest sum (point) is determined as the optimal code (Chord) (C16).

  Therefore, according to the present invention, even if a performance sound by a user performance or the like does not include a sound corresponding to the root, it is possible to detect an appropriate chord having a route that has not been performed, and the user can play both hands, etc. You can get an automatic accompaniment with appropriate chords while devoting yourself to free performance. In particular, even if a point table that does not consider the low point setting for the role of route (r) is used, for candidate codes (ChordList) determined to have the role of root, points are extracted and total points are calculated Therefore, it is possible to reliably detect a chord having a route that has not been played by the user.

1 shows a hardware configuration example of a code detection device according to an embodiment of the present invention. 2 shows an image of code detection timing according to an embodiment of the present invention. 4 shows an example of a point table by degree name according to an embodiment of the present invention. The 1st part of the automatic accompaniment performance processing flow by one Example of this invention is shown. The 2nd part of the automatic accompaniment combined performance performance processing flow by one Example of this invention is shown. The 3rd part of the automatic accompaniment combined performance processing flow by one Example of this invention is shown. 2 shows a note event processing flow according to one embodiment of the present invention. 2 shows a part of a code detection processing flow according to an embodiment of the present invention. The other part of the code | cord | chord detection processing flow by one Example of this invention is shown. 2 shows a part of a role extraction processing flow according to an embodiment of the present invention. The other part of the role extraction processing flow by one Example of this invention is shown. A part of an example of a point table by degree name according to an embodiment of the present invention is shown. The other part of the example according to the point table classified by degree name by one Example of this invention is shown.

[Overview of system configuration]
FIG. 1 shows a hardware configuration example of a code detection apparatus according to an embodiment of the present invention. A chord detection apparatus according to an embodiment of the present invention is a kind of computer having an electronic music information processing function, and can be embodied in the form of an electronic musical instrument. As shown in FIG. 1, the chord detection device includes a central processing unit (CPU) 1, a random access memory (RAM) 2, a read only memory (ROM) 3, an external storage device 4, a performance information acquisition unit (performance information input unit). 5), other operation elements 6, a display 7, a sound source 8, an automatic accompaniment device 9, a communication interface (I / F) 10, and the like, and these elements 1 to 10 are connected via a bus 11. .

  The CPU 1 constitutes a data processing unit together with the RAM 2 and the ROM 3, and uses the clock of the timer 12 to execute various music information processing according to a predetermined control program including an automatic accompaniment performance processing program. It is used as a work area for temporarily storing various data necessary for these processes. For example, in the automatic accompaniment performance mode in which automatic accompaniment performance processing is executed, the timer 12 measures various set times set for detecting and applying chords under the control of the CPU 1. Various registers (NoteList, ChordList, Chord, sTime, eTime, Key, ResultList, etc.) necessary for code detection and application are provided. In addition, various control programs and various control data necessary for executing these processes are stored in the ROM 3 in advance.

  The external storage device 4 includes a storage medium such as a semiconductor memory such as an HD (hard disk), an FD (flexible disk), a CD (compact disk), a DVD (digital multipurpose disk), and a flash memory, and a driving device thereof. Arbitrary information such as a control program, degree name point table (PT), control data such as various rules, and various music data can be stored in an arbitrary storage medium. The storage medium may be detachable or may be built in the code detection device, and the detachable recording medium includes a USB memory.

  The performance information acquisition unit 5 includes a performance operator such as a keyboard, and a performance operation detection circuit that detects operation of the performance operator and introduces performance operation information corresponding to the detected contents to the data processing units (1 to 3). Is done. The other operation unit 6 includes other operation units (setting operation units) such as key switches, and a setting operation detection circuit that detects operations of these operation units and introduces corresponding operation information to the data processing unit. The The data processing unit (1-3) controls each part of the chord detection device based on operation information from the performance information acquisition unit 5 and the other operation unit 6, and for example, a performance corresponding to a performance operation input from the performance operation unit 5 Data can be sent to the sound source 8 or can be operated in the automatic accompaniment performance mode by operating a mode setting button in the operation unit 6.

  The display unit 7 includes a display such as an LCD for displaying various information necessary for performance and setting, a built-in lamp attached to the switches in the operation units 5 to 6, and the like. Controls with commands from, and provides display assistance for performance and setting operations.

  The sound source 8 includes a sound source unit and a DSP, and generates a musical sound signal based on performance data obtained from the performance operation information of the performance information acquisition unit 5 or based on music data read from the storage device 4. A predetermined effect is given to this musical sound signal. The sound system 13 connected to the sound source 8 includes a D / A converter, an amplifier, a speaker, and the like, and generates a musical sound based on a musical sound signal output from the sound source 8. In the automatic accompaniment performance mode, the automatic accompaniment device 9 sets the tempo of automatic accompaniment with the tempo clock from the timer 12, and according to this tempo clock, the accompaniment corresponding to the chord provided from the data processing unit (1-3) Generate automatic accompaniment sounds based on style data.

  The communication I / F 10 includes a music wired I / F such as MIDI, a general-purpose network I / F such as USB, or a general-purpose short-range wireless I / F such as wireless Lan, and can communicate with the external electronic music apparatus MM. it can. For example, MIDI format music data can be acquired from the external electronic music device MM and stored in the storage device 4.

[Code detection timing]
In the chord detection apparatus according to one embodiment of the present invention, the chord is detected based on the performance data input from the performance information acquisition unit 5 at a predetermined bar or beat timing by the automatic accompaniment performance processing. Is automatically applied to automatic accompaniment. FIG. 2 shows an example of code detection timing according to one embodiment of the present invention.

  FIG. 2A is an example of the code detection reference position, and the horizontal axis indicates a time axis in which time advances in the right direction. The chord detection reference position T2 indicated by ◎ is a musical timing such as a predetermined bar or beat timing preset by a user operation with respect to the performance data, and instructs the user to detect or apply chords. It becomes a standard of timing. In this example, the first beat and the third beat are set as the chord detection reference position T2 for the performance data of one measure = 4 beats. On the other hand, FIG. 2B is an example of the code detection timing, and the scale of the time axis (horizontal axis) in which the time advances in the direction of the right arrow is larger than that in FIG. .

  The code detection timing starts at a code detection timing start position (time) T1 a predetermined time before the code detection reference position T2, and ends at a code detection timing end position (time) T3 after a predetermined time from the position T2. As described above, the timings T1 to T3 for performing the chord detection are obtained by setting the time widths T1 to T2 and T2 to T3 before and after the predetermined beat position T2, respectively. Then, T1 to T2 = 250 ms and T2 to T3 = 50 ms. Here, when performance data (note event) is input in response to a performance operation (key depression) such as playing both hands during the chord detection timing (time width) T1 to T3, chord detection is instructed at the chord detection timing end time T3. Then, chord detection is performed based on the input performance data (note event) and the key at that time.

  In this chord detection device, performance data sounded within the time interval T1 to T3 is a target of chord detection, and the pitch of each performance sound (note event, note data) constituting the target performance data at time T3. By referring to the point table (PT) by degree name, candidate chords that can be chords in the key set at that time are extracted, and the role of each performance sound identified for each extracted candidate chord is extracted. Find the corresponding musical point (importance). Then, the sound points of the candidate codes are summed, and the candidate code with the highest total point is detected as the optimum code. Further, at the same time as detecting the chord at time T3 in this way, the detected chord is applied to the automatic accompaniment and is sequentially added to the chord detection result list.

  In this case, if the chord detection is performed after removing the ornamental sound or the note data that is presumed to be mistouched from the performance data within the target time width T1 to T3, the accuracy is further improved. Further, the key information used at the time of detecting the chord may be specified by the user before the performance, or may be used at any time along the performance. In the latter case, the key may be detected by the conventional technique.

  During the automatic accompaniment performance process, the chord detection timing start position T1, chord detection timing end position T3, performance data (note event), key information, candidate chord, detected chord, chord detection result list are stored in the RAM 2 respectively. Registers: sTime, eTime, NoteList, Key, ChordList, Chord, and ResultList. Each register name is also used to indicate the contents of the stored information. Each time a chord is detected, the key information (Key) at that time is preferably stored in the chord detection result list (ResultList) in association with the detected chord (Chord).

  The chord detection reference position is not limited to the beat position as in this example, but can be a bar position (for example, every two bars) depending on the tempo and time signature. Further, the time widths T1 to T2 and T2 to T3 before and after the reference position are set in units of ms in this example, but may be set in terms of the note length, the number of beats, the number of clocks, or the like.

[Point table by degree name]
In this code detection apparatus, a point table for each degree name (also referred to as a code-specific point table) is used to obtain points corresponding to each candidate code at the time of code detection. FIG. 3 shows an example of a point table by degree name according to one embodiment of the present invention. The degree name-specific point table PT includes a note point table (columns 5 to 11) for obtaining points of each note (r, 3, 5,. The priority point table (fourth column) for obtaining priority points (Prior) is grouped into one table for Major and Minor keys, and information on whether code functions and diatonic scale codes ( The second and third columns) are added. The degree name point table (Major key) PT in FIG. 3 is a table relating to all codes that can be candidate codes in the Major key (major key), and a similar table is also prepared for the minor key (minor key) (not shown). )

  In FIG. 3, the first column (first column) indicates degree name information (DegreeName) (also referred to as code information, which is simply referred to as a degree name in the following description) prepared in the degree name-specific point table PT. There are many degree names other than those shown. Each degree name (DegreeName) is a frequency based on the key of the key (tonic) [the frequency of the root (root). Example: I, II, III, IV, V, ...] and code type [Example: No symbol (major), m (minor), 7, 6, Maj7 (major 7), m6 (minor 6), m7 (minor) 7), add9 (9th added major),... In the figure, “b” represents “♭” (flat), and the same applies to FIGS. 10, 12, and 13 described later.

  In the degree name point table PT, various information in the second column (second column) and below is recorded corresponding to each degree name (DegreeName) in the first column (first column). The diatonic information in the second column indicates whether the code represented by each degree name (DegreeName) is a diatonic scale code (○) or not (×), and the function information in the third column is the degree information This indicates whether the function of the name (DegreeName) is tonic (T), subdominant (S), dominant (D), or subdominant minor (SM). The priority point information (Prior) in the fourth column represents the priority of the degree name (DegreeName) itself as a point value, and is also called a code priority point or a degree name priority point. On the other hand, the fifth to eleventh columns constitute a note point table section in which note point information representing musical importance is set for each note (role: r, 3, 5,...) Characterizing the chord. ing.

  First, the point information in each column of the fifth to ninth columns represents the musical importance of each chord constituent sound constituting the chord as a point value. Specifically, the route point information in the fifth column indicates a point corresponding to the root (root note) of the chord constituent sound <abbreviation “r”>, and the third-degree point information in the sixth column indicates the chord constituent The 5th point information in the seventh column indicates the point corresponding to the 5th tone <abbreviation “5”> of the chord constituent sound, The fourth voice point information in the 8th column is the fourth voice of the 6th (6th), 7th (7th), or 7th (Maj7th) long voice <abbreviation for the root The point corresponding to “4”> indicates the alternative point information in the ninth column, which is 5 degrees (♭ 5th) or 5 degrees (# 5th) less than the root (root sound) in the chord constituent sound. Points corresponding to the fifth-degree changing sound (alternate chord tone) <abbreviation "a"> are shown.

  The tension note point information in the 10th column points to the musical importance of the tension note <abbreviation “t”> that gives a sense of tension with a non-harmonic sound placed above the basic chord structure of the chord. The other point information in the 11th column (the rightmost column) is a musical importance for other notes that do not correspond to chord constituent sounds or tension notes, such as the void note that should be excluded in the structure of the chord sound. Is represented by a point value.

  In this note point table section (columns 5 to 11), it is assumed that a sound having the role of the root in the chord constituent sounds is not played, so the point with respect to the root (r) is a negative value (for example, “− 50 ”) (exceptionally“ 0 ”value may be taken), and the third tone (3), the fourth voice (4), and the alternate chord tone (a) have a strong role in determining the chord type. A high point is set for the tension note, and a point suitable for the intended voicing is set for the tension note. On the other hand, for the performance sound (others) that causes dissonance in the chord, the importance is lowered and the point is set to be lower.

  In this chord detection device, when chord detection is performed, chords (ChordList) to be candidates are extracted according to the key (Key) when performance data to be detected is input. For example, some combinations of types of codes that can be used in a predetermined key are stored in advance, a desired combination is selected at the time of code detection, and codes corresponding to the selected combination are extracted as candidate codes (ChordList). In addition, in the point table PT by degree name shown in FIG. 3, not only the point information (4th to 11th columns) but also the degree name (DegreeName: 1st) of each code as shown in the 2nd and 3rd columns. Since function information indicating what is a diatonic scale code or function is added to the column), refer to the additional information using the degree name point table PT. Thus, a candidate code (ChordList) can be extracted.

  For example, all the codes (DegreeName) corresponding to the diatonic scale code (second column information = “◯”) of the key at that time may be extracted as candidate codes (ChordList). Alternatively, in the case of code detection after the second time, the function (third column information) of the previously detected code (Chord) is examined. For example, if it is a dominant (D), the process proceeds to a tonic (T). Thus, a chord (DegreeName) that can be musically advanced from the previously detected chord (Chord) may be extracted as a candidate chord (ChordList). Note that such additional information may not be included in the degree name-specific point table PT, and a reference table different from the table PT may be prepared.

  Once the candidate chord (ChordList) is extracted, what role each performance sound (key press sound, Note) included in the target performance data (NoteList) plays in the extracted candidate chord (ChordList) (Which component sound, tension note, or void note) is identified, and points corresponding to the identified roles (each component sound, tension note, and void note) are acquired from the degree name point table PT. Then, the points (importance) for all performance sounds (NoteList) are summed for each candidate chord, and the candidate chord with the highest sum total point is selected as the chord (Chord) most suitable for the target performance data.

  Here, in the point table PT by degree name used for acquiring points, as described above, a low value such as a negative value (“−50”) is set for the role of the root in all codes (DegreeName). Accordingly, the candidate chord in which the performance sound (Note) in the performance data (NoteList) plays the role of the root (r) is not selected as the optimum chord (Chord). That is, the optimum chord (Chord) is detected from the candidate chords in which all performance sounds (NoteList) play roles other than the root (r, 3, 5, 4,...). Therefore, when the user does not play the route, it becomes possible to detect a chord having a route that was not played.

  In order to detect a chord having a route that has not been played without adjusting the point setting for the route in the point table PT, for example, first, from among candidate chords (ChordList) listed as candidates, The user performance sound (NoteList: Note) selects the candidate code that does not play the root role (= plays the role other than the root), and then selects the total points from the selected “candidate codes that play the role other than the root” There is a method of selecting the highest chord as the best chord (including many notes).

  As described above, in the chord detection system according to one embodiment of the present invention, when performance data (NoteList) is input in response to a performance operation such as double-handed playing by the user, chord detection is performed every predetermined bar or every predetermined beat. At timings T1 to T3, a candidate code (ChordList) is extracted according to the key (Key) at that time. Then, for each extracted candidate chord (ChordList), each performance sound (Note) of the input performance data (NoteList) is a plurality of notes characterizing the chord [root (r), 3 degrees (3), 5 degrees ( 5), 4th voice (4), Altered system (a), Tension note (t), Avoid note, etc.) The optimal code (Chord) is detected from the candidate codes having the role. For example, for each possible chord (DegreeName), a plurality of notes that characterize the chord (DegreeName) [root (r), third degree (3), fifth degree (5), fourth voice (4), altered system (a) Point indicating musical importance for the role of (tension note (t), void note, etc.) is set, and the point table PT in which the point for the role of root (r) is set low for any chord is referred to Then, for each candidate code (ChordList), the points for the determined roles are extracted and summed, and the candidate code having the highest total point is determined as the optimum code (Chord). Alternatively, for each chord (DegreeName) that can be a candidate, a point table in which points indicating musical importance are set for the role of each note (r, 3, 5, 4,...) Characterizing the chord (DegreeName) ( In particular, all pitch information (NoteList: Note) has a role other than root (r) (3,5,4, ...). For each candidate code determined to have (ChordList), the points for roles (3, 5, 4, ...) other than the determined route (r) are extracted and summed, and the candidate code with the highest total point is optimized. Chord is determined.

[Example of automatic accompaniment performance processing flow]
4 to 6 are flowcharts showing an example of the operation of the automatic accompaniment performance processing according to one embodiment of the present invention. In this chord detection apparatus, the automatic accompaniment combined performance mode setting button in the controller 6 is operated to operate the automatic accompaniment combined performance mode when the electronic musical instrument is operating in the normal performance mode. The process is executed and a performance using automatic accompaniment can be performed. When the automatic accompaniment performance process starts, the CPU 1 displays a performance condition setting screen on the display unit 7 in the first step P1, and according to the user operation, the performance tempo, time signature, accompaniment style selection, volume, Set performance conditions such as the performance tone before the performance starts.

  In the next step P2, a chord detection condition setting screen is displayed on the display, and in accordance with a user operation, chord detection timings T1 to T3 and various rules related to chord detection, for example, key acquisition method, chord candidate extraction Set method, degree name-specific point table PT, code priority point (Prior), bottom note point, etc. Here, the bottom note point in the rule is a point that is added when the performance sound with the lowest pitch is the root of the candidate chord in the performance data (NoteList) to be detected. That is, if the bottom note point is further added when the lowest note of the performance sound at the time of chord detection hits the root of the candidate chord, for example, chords of the same constituent sound such as C6 and Am7 can be distinguished. This bottom note point may be a fixed value such as 20 points, or may be set for each chord type. Editing settings may be possible by the user.

  An example of setting various rules will be described. For key acquisition, a method specified in advance by the user, a method specified by operating the key specifying operator in the operator 6 during performance, and as required by the user's performance There is a method of using the detected key (including specification of a specific key detection method). For chord candidates, the method of extracting only the key diatonic scale chord, the method of extracting all the chords that can be used in the key, and the constituent sounds of the chords that can be used in the key are included in the target performance data (NoteList) There is a method of extracting a chord having one sound or more. For the degree name-specific point table, there are setting operations such as selecting a desired type from a plurality of types of tables and editing point values in the table. If code priority points (Prior) and bottom note points are not set in the degree name-specific point table, they are controlled according to control data such as the code priority point table (also called the degree name priority point table) in which these points are set. Set.

  In subsequent step P3, the point table PT by degree name is read. Here, if the degree name point table PT is not a table integrated with the code priority point table as shown in FIG. 3, the code priority point table provided separately is also read. In the next step P4 (FIG. 5), various registers in the RAM 2 used for code detection and application are initialized. These registers include NoteList, ChordList, Chord, sTime (code detection timing start position), eTime (code detection timing end position), Key, ResultList, and the like.

  When the preparations before the performance are completed by the processes of Steps P1 to P4, the first chord detection timing start position (sTime) and the chord detection timing end are determined from the contents of the chord detection timings T1 to T3 set in Step P2 in Step P5. The position (eTime) is calculated and stored in the corresponding start and end position registers: sTime and eTime, respectively, and the process proceeds to Step P6. In the example of FIG. 2, sTime = 250 ms before the beat as the reference position and eTime = 50 ms after the beat as the reference position. However, only the first code detection timing start position (sTime) stored in the start position register: sTime is set to the first code detection reference position T2.

  In Step P6, the user is asked whether or not to return to the normal performance mode without using the automatic accompaniment, and when it is determined that the normal performance mode return button is operated to return to the normal performance mode (P6 = YES), this automatic End the accompaniment performance mode and return to the original normal performance mode. On the other hand, when it is determined that the automatic accompaniment performance mode is to be continued by operating the continue button (P6 = NO), the process proceeds to step P7, and an instruction to start automatic accompaniment by operating the automatic accompaniment start button has been accepted. If no automatic accompaniment start instruction is given (P7 = NO), the process returns to step P6. Further, when an instruction to start automatic accompaniment is received at step P6 (P7 = YES), the timer 12 is started at step P8, and the process proceeds to step P8.

  In Step P9, it is determined whether or not an automatic accompaniment stop instruction by operating the automatic accompaniment stop button has been accepted. When an automatic accompaniment stop instruction is received (P9 = YES), the timer 12 is stopped in Step P10, In step P11, the user is asked whether or not to change the setting of performance conditions such as accompaniment style and chord detection conditions such as chord detection timing. When it is determined that the setting change button is operated and the setting is changed (P11 = YES), the process returns to Step P1 (FIG. 4), and necessary settings and calculations are performed in Steps P1 to P5. Return. On the other hand, when the setting is not changed (P11 = NO), the process immediately returns to step P6.

  When the automatic accompaniment stop instruction is not accepted in step P9 (P9 = NO), the process proceeds to step P12 to determine whether or not a note event based on the performance operation has been accepted. When a note event is accepted (P12 = YES), note event processing (see FIG. 7) is performed in step P13, and then the process proceeds to step P14 (FIG. 6). In the note event processing, note events that occur between chord detection timings T1 to T3 are recorded in the performance data register: NoteList as performance data to be chord detected. If no note event is accepted (P12 = NO), the process immediately proceeds to step P14.

  In step P14, it is determined whether or not the code detection timing is reached, that is, whether or not the end time eTime has been reached. When the time eTime has been reached (P14 = YES), first, in step P15, key information is acquired and adjusted. Store in register: Key. In the next step P16, code candidates corresponding to the key information key are extracted in accordance with the extraction method set in step P2, stored in the candidate code register: ChordList, and the process proceeds to step P17 to execute code detection processing (FIGS. 8 to 8). 9). In the chord detection process, a desired chord Chord is detected from the target performance data (NoteList) and the extracted chord candidate (ChordList), and the detected chord Chord is output to the automatic accompaniment device 9 in the next step P18. In step P19, the code Chord is added to the end of the code detection result register: ResultList, and the process proceeds to step P20. That is, every time a code is detected, the key information at that time is stored in association with the detected code. If there is no chord, that is, if the desired chord cannot be detected by the chord detection process, the process proceeds from step P17 to step P20.

  In step P20, the start and end positions (sTime, eTime) of the next chord detection timing are calculated from the set contents of chord detection timing, and the respective registers: sTime, eTime are updated. In step P21, the performance data and chord are updated. Candidate registers: NoteList and ChordList are initialized. Then, when it is determined in step P14 that the end time eTime has not been reached (P14 = NO) or after the process of step P21, the process returns to step P9 (FIG. 5).

<Note event processing flow example>
FIG. 7 is a flowchart showing an operation example of the note event process performed in step P13 (FIG. 5) of the automatic accompaniment performance process. First, in step N1, the CPU 1 determines whether or not the timer 12 currently indicates a code detection timing (between sTime and eTime). If it is within the range of the code detection timing (N1 = YES), step N2 Thus, it is determined whether or not the note event received in step P12 (FIG. 5) is note-on. If the note is on (N2 = YES), in step N3, the sound source 8 is caused to perform sound generation processing in accordance with the note event, and in the next step N4, the note event information on which the note is turned on is stored in the performance data register. : Add to NoteList. On the other hand, if the note is off (N2 = NO), the musical sound is silenced by the note event in step N5, and the note event information that has been turned off is deleted from the register: NoteList in step N6.

  If it is not the chord detection timing (sTime to eTime) (N1 = NO), the process proceeds to step N7, where it is determined whether the note event received in step P11 (FIG. 4) is note-on. If there is (N7 = YES), in step N8, the sound source 8 performs sound generation processing, and if it is note-off (N7 = NO), the mute processing is performed. After the processes of steps N4, N6, N8, and N9, the note event process is terminated, and the process returns to step P14 (FIG. 6) of the automatic accompaniment performance process.

<Example of code detection processing flow>
8 to 9 are flowcharts showing an example of the chord detection process performed in step P17 (FIG. 6) of the automatic accompaniment performance process. In the first step C1, the CPU 1 determines whether or not the performance data register: NoteList is empty (no data). If not (C1 = NO), the chord candidate register: ChordList is set in step C2. It is determined whether or not it is empty. If it is not empty (C2 = NO), the process proceeds to step C3. If the performance data register: NoteList is empty (C2 = YES) or the chord candidate register: ChordList is empty (C2 = YES), the process returns to step P18 (FIG. 6) of the automatic accompaniment performance process.

  In step C3, one candidate code is converted into a degree name in order from the top of the code candidate register: ChordList (the second and subsequent codes), and this is converted to a degree name register (also referred to as a code information register): DegreeName In the next step C4, the value “0” is entered in the point value register: point. In the subsequent step C5 (FIG. 9), pitch information is extracted from the performance data register: NoteList in order from the top of the note list (the second and subsequent items are the next), and this is extracted as the performance sound register: Store in the Note and proceed to Step C6. In step C6, a role extraction process (see FIGS. 10 to 11) for extracting the role of the performance sound Note in the chord indicated by the degree name DegreeName is executed, and in the next step C7, the role extraction process of step C6 extracts “ It is determined whether or not the “role in the code of DegreeName” is “root”.

  When it is determined in step C7 that the role is “root” (C7 = YES), the process proceeds to step C8 to determine whether or not the code indicated by the degree name DegreeName is the last code in all candidate codes ChordList. If it is not the last code (C8 = NO), the process proceeds to step C9. In step C9, the code indicated by the degree name DegreeName is deleted from the candidate code register: ChordList, and the process returns to step C3 (FIG. 8) to process the next candidate code in all candidate codes ChordList in steps C3 to C7. repeat. On the other hand, when it is determined in step C8 that it is the last code, in step C10, the code indicated by the degree name DegreeName is deleted from the candidate code register: ChordList, and then the process proceeds to step C16.

  When it is determined in step C7 that the role is not “root” (C7 = NO), the process proceeds to step C11, and by referring to the degree name point table PT, the “role in the code of DegreeName” extracted in step C6. The corresponding point is acquired, added to the point value point, and the process proceeds to step C12. Note that this role can be further divided according to the type of tension note depending on the specification of the degree name point table PT (see FIGS. 12 to 13). In step C12, it is determined whether or not the performance note register: Note indicates the pitch information of the last note event information in the performance data register: NoteList. If it is not the last note event pitch information (C12 = NO), returning to step C5, the processes of steps C5 to C7 are repeated for the next note event information in the performance data NoteList. Then, when the process of steps C5 to C7 → C11 is performed for the last note event pitch information in the performance data NoteList (C12 = YES), the process proceeds to step C13.

  In step C13, a priority point (Prior) corresponding to the code indicated by the degree name DegreeName is obtained by referring to the degree name point table PT, and added to the point value point. In step C14, the point value point is changed to the degree value point. All candidate codes indicated by the name DegreeName are stored in association with candidate codes in the ChordList. In the next step C15, it is determined whether or not the code indicated by the degree name DegreeName is the last code in all candidate codes ChordList. If it is not the last code (C15 = NO), the process proceeds to step C3 (FIG. 8). Returning, the process of steps C3 to C7 is repeated for the next candidate code in all candidate codes ChordList. Then, when the processes of steps C3 to C7 → C11 to C14 are performed for the last code in all candidate codes ChordList (C15 = YES), the process proceeds to step C16.

  In step C16, one candidate code with the highest point value point stored in association with each candidate code in all candidate codes ChordList is detected, stored in the code register: Chord, and when the processing in step C14 is completed, The chord detection process is terminated, and the process returns to step P18 (FIG. 6) of the automatic accompaniment performance process. When determining one code from among the candidate codes in step C14, if there are a plurality of candidate codes having the highest point value point (when the points are arranged at the same point), one is determined by an appropriate method. To do. For example, a priority rule that defines the characteristics of a code to be selected with priority, such as a code with a small or large number of detections, a code with a small or large number of tensions, and a diatonic scale code, is prepared and set in step P2. It is preferable to design in such a manner.

  In the above description, an example of an operation that can be realized even when the point table by degree name PT is not set to a low point for the role of the root is shown, but as shown in FIG. When a sufficiently low value is set for the role of “root” in PT, the process of steps C7 to C10 is omitted and the process of step C6 is immediately advanced to the process of step C11 as shown by the broken line in FIG. Also good.

<Role extraction process flow>
10 to 11 are flowcharts showing an example of the code detection process performed in step C6 (FIG. 9) of the code detection process. In the first step F1, the CPU 1 starts from the main tone (tonic) of the key information key and the degree name DegreeName, the chord root, 3rd and 5th [minor 7th flat 5th [m7 (♭ 5)] and augment [aug] Is stored in the “root” register, “3rd” register, and “5th” register in the RAM 2. Here, the numbers of semitones from the main sound are determined for the root, 3rd and 5th sounds according to the chord type. For example, in the case of Key = CMajor, DegreeName = IVMaj7, “root” = F ), “3 degrees” = A (La), and “5 degrees” = C (Do).

  In the next step F2, it is determined whether or not the pitch name of the performance sound information Note is equal to the value of the “root” register. If it is the value of the “root” register (F2 = YES), the performance sound is determined in step F3. The role of the information note is determined to be “root”, otherwise (F2 = NO), the process proceeds to step F4. In step F4, it is determined whether or not the pitch name of the performance sound information Note is equal to the value of the “three times” register. If it is the value of the “three times” register (F4 = YES), the performance sound is determined in step F5. The role of the information note is determined to be “three times”, otherwise (F4 = NO), the process proceeds to step F6. In step F6, it is determined whether or not the note name of the performance sound information Note is equal to the value of the “5th” register. If it is the value of the “5th” register (F6 = YES), the performance sound is determined in step F7. The role of the information Note is determined to be “5 degrees”, otherwise (F6 = NO), the process proceeds to Step F8. When the processes of steps F3, F5, and F7 are completed, the role extraction process is terminated and the process returns to step C7 (FIG. 9) of the code detection process.

  In step F8, it is determined whether or not the code type of the degree name DegreeName is “m7 (♭ 5)” (minor 7 flat 5). If the chord type is “m7 (♭ 5)” (F8 = YES), the process proceeds to step F9, where the note name of the performance note information Note is reduced by 5 degrees (♭) with respect to the note name in the “root” register. 5th), and if it is a decrease of 5 degrees (F9 = YES), the role of the performance sound information Note is determined to be “alternate” in step F10. On the other hand, if the code type is not “m7 (♭ 5)” (F8 = NO), the process proceeds to step F11 to determine whether the code type of the degree name DegreeName is “aug” (an augment). If the chord type is “aug” (F11 = YES), the process proceeds to step F12, and whether the note name of the performance sound information Note is increased by 5 degrees (# 5th) with respect to the note name of the “root” register. If NO in step F10 (F12 = YES), the role of the performance sound information Note is determined to be "alternate" in step F10. When the process of step F10 is completed, the role extraction process is terminated and the process returns to step C7 (FIG. 9) of the code detection process.

  When it is determined in step F11 that the code type is not “aug” (F11 = NO), the process proceeds to step F13 (FIG. 13), and the code type of the degree name DegreeName is “6”, “6sus4” (6 suspended). 4) or “m6” (minor 6). Here, if the chord type is any of “6”, “6sus4”, and “m6” (F13 = YES), the process proceeds to step F14, and the note name of the performance sound information Note is the sound of the “root” register. It is determined whether or not the name is 6 degrees (6th), and if it is 6 degrees (F14 = YES), the role of the performance sound information Note is determined to be “fourth voice” in step F15. On the other hand, when it is determined in step F13 that the code type is neither “6”, “6sus4”, or “m6” (F13 = NO), the process proceeds to step F16, and the code type of the degree name DegreeName is “ It is determined whether or not it is a Maj7 (major 7) system such as “IMaj7” (1 degree / major 7) and “IVmMaj7” (4 degrees / minor major 7). Here, if the chord type is Maj7 type (F16 = YES), the process proceeds to step F17, and whether or not the pitch name of the performance sound information Note is 7 degrees (Maj7th) long with respect to the pitch name of the “root” register. If it is 7 degrees long (F17 = YES), the role of the performance sound information Note is determined to be “fourth voice” in step F15. If it is determined in step F16 that the code type is not Maj7 (F16 = NO), the process proceeds to step F18, and the code type of the degree name DegreeName is “IIm7” (twice / minor 7), “V7” ( It is determined whether it is an m7 (minor 7) system to a 7 (seven) system such as “5 degrees / Seven)” and “VII7sus4” (7 degrees / Seven Suspended 4). Here, if the chord type is the m7 system to the 7th system (F18 = YES), the process proceeds to step F19, and the pitch name of the performance sound information Note is 7 degrees (7th) shorter than the pitch name of the “root” register. In step F15, the role of the performance sound information Note is determined to be “fourth voice” if it is short 7 degrees (F19 = YES). When the process of step F10 is completed, the role extraction process is terminated and the process returns to step C7 (FIG. 9) of the code detection process.

  When it is determined in step F9 that it is not a decrease of 5 degrees (F9 = NO), when it is determined that it is not an increase of 5 degrees in step F12 (F12 = NO), and when it is determined that the length is not 6 degrees in step F14 (F14 = NO) When it is determined at step F17 that it is not 7 degrees long (F17 = NO), when it is determined at step F18 that the code type is neither m7 system nor 7 system (F18 = NO), or it is not short 7 degrees at step F19. (F19 = NO), the process proceeds to step F20, where it is determined whether or not the pitch name of the performance sound information Note is a tension note with respect to the chord of the degree name DegreeName in the current key. Here, the tension note has a semitone distance number from the root sound depending on the chord type (for the root, any of ♭ 9th, 9th, # 9th, 11th, # 11th, ♭ 13th, 13th) 1-3), for example, when Key = CMajor and DegreeName = IVMaj7, the sound is G (So), B (Sh), and D (Le). If it is a tension note (F20 = YES), the role of the performance sound information Note is determined as “tension note” in step F21. Otherwise (F20 = NO), the performance sound information Note is determined in step F22. The role of “Other” is determined. When the processes of steps F21 and F22 are completed, the role extraction process is terminated and the process returns to step C7 (FIG. 9) of the code detection process.

[Point table by degree name (2)]
The degree name point table PT described in FIG. 3 is a table in which note points indicating the importance of the role of notes such as constituent notes, tension notes, and void notes based on the corresponding degree names are set for each possible chord. However, note points can be set in more detail. 12 to 13 show other examples of degree name point tables according to an embodiment of the present invention. In this degree name-specific point table, the same information as the table of FIG. 3 is set in the first to fifth columns, but the sixth to twenty-second columns are shown for the Root in the fifth column. Points (importance) corresponding to the role of the sound indicating the pitch of the street (m3rd, 3rd, 4th, ..., 13th) are set, and each sound including the root in the 5th to 22nd columns is characterized by a chord Role information representing a note (role) is added and displayed in the note point display frame as follows in FIGS.
The symbol “r” at the upper left of the display frame represents the root of the chord component sound, the symbol “3” represents the third tone of the chord component tone, the symbol “5” represents the fifth tone of the chord component sound, The symbol “4” represents the fourth voice of the chord constituent sound [6th, 7th, Maj7th], and the symbol “a” represents the altered chord tone [♭ 5th, # 5th (aug5th)] in the chord constituent sound. The symbol “t” represents a tension note. In addition, if the entire display frame is shaded, it indicates that it is not used due to a different name and the same name (same on the keyboard but different on the keyboard). Etc.).

  By using such a degree name point table PT, it is possible to simultaneously obtain the role and point in the chord for each performance sound (pitch information). Also, not only chord constituent sounds but also tension notes can be set for each type, and chord detection can be performed with high accuracy.

  As described above, the degree name-specific point table PT includes, for each degree name (DegreeName), each chord constituent sound (r, 3, 5, 4, a), each tension note (t), and void note (no symbol). For each frequency: Root (1st), m3rd, 3rd, 4th, ... 13th, points indicating the importance are prepared. In particular, each point of performance sound by the user is referred to this point table PT for each candidate code. It is suitable for the method of summing up the points and selecting the candidate code with the highest point total value. In other words, this point table PT sets the point with respect to the root (r) to a negative value (in the example shown, since it is intended for a jazz performance, the chord root sound that does not appear in the jazz system is used) Exceptionally “0” value may be taken), 3rd tone (3rd-Note and 4th-Note) (6th-8th columns), 4th voice (6th, 7th, Maj7th) [12th, 14th, 15th row] and Altered chord tone (♭ 5th, aug5th) [9th, 11th row] are set to high points, and each tension note is musical as jazz voicing. By setting an appropriate point from the viewpoint of importance, it becomes possible to detect a chord having a route that was not played when the route was not played. Note that the point table PT may be editable by the user. Moreover, although the low importance level is represented by a negative value, the point may be set to 0 or more, and the higher the numerical value, the higher the importance level may be.

[Various Embodiments]
The preferred embodiment of the present invention has been described above with reference to the drawings. However, this is merely an example, and the present invention can be variously modified without departing from the spirit of the invention. For example, the chord detection timing may be determined by the tempo and the accompaniment style to be used, or may be set by the user. Further, it may be a timing when a specific operation element such as a switch is operated, or may be a predetermined beat timing + an operation element operation timing. For example, when a change in tempo is detected, it may be changed from every 2 beats to every 1 beat. Further, as in the embodiment, a time width (T1 to T3) for receiving input of target performance data may be provided.

In the embodiment, a point table for each degree name (PT) in which note points are set for every chord that can be a candidate is used. In addition, a desired type of point table may be selected by a user operation. Moreover, editing and creation may be possible by the user.
In addition to the note point table, a code priority point table (degree name priority point table) in which a code priority point (degree name priority point) indicating the priority of the degree name itself corresponding to the candidate code is set can be provided. In this case, similarly, a plurality of types of code priority point tables may be prepared and selectable, or the table may be edited or created by the user.
Further, a table for each degree name of the chord as in the embodiment may be used, and the note point table may be a table for each chord type.

In the embodiment, the automatic accompaniment is generated based on the detected chord according to the performance data, but a harmony sound may be generated based on the detected chord. Or the utilization method of displaying the information of the detected code | cord | chord on a display screen sequentially is also considered.
When storing the detected chords, all the chords detected after the start of the performance may be stored in a list format or the like, or the latest chord or an arbitrary number may be stored and updated for each detection. May be. The detected code may store a code name, or a degree name associated with the key information at that time. Both the code name and the degree name may be stored.

In the embodiment, the performance data to be input is assumed to be real-time performance data by the user. However, for example, a method of detecting chords while sequentially reproducing recorded performance data without prefetching is also conceivable. Alternatively, performance data may be input from a device such as a musical instrument connected to the outside.
The performance data input means (performance operator) is not limited to a keyboard, and may be a stringed instrument type such as a guitar. When the user's performance input sound is an audio signal, at least at each chord detection timing, it is converted into note information having at least sounding timing information and pitch information before referencing performance data to select one chord from candidate chords It only has to be done.

T1-T3 code detection timing [T1 = start (sTime), T3 = end (eTime)],
T2 code detection reference position,
Point table by PT degree name.

Claims (4)

For each chord that can be a candidate, a point table that stores a point table in which points indicating musical importance are set for the roles of multiple notes that characterize the chord, and points for the root role are set low for any chord Storage means;
Performance data acquisition means for acquiring performance data;
Key information acquisition means for acquiring key information;
Code detection instruction means for instructing code detection at a predetermined code detection timing;
Candidate code extraction means for extracting a candidate code based on the key information acquired by the key information acquisition means when code detection is instructed by the code detection instruction means;
Pitch information extraction means for extracting pitch information considered valid at the chord detection timing from the performance data acquired by the performance data acquisition means when the chord detection is instructed by the chord detection instruction means;
When code detection is instructed by the code detection instructing means, for each candidate code extracted by the candidate code extracting means, each pitch information extracted by the pitch information extracting means has a plurality of characterizing codes. Note role discriminating means for discriminating which note role of the note has,
When the chord detection instruction is instructed by the chord detection instructing unit, the candidate role discriminating unit has determined that all pitch information extracted by the pitch information extracting unit has a role other than the root. Code detecting means for detecting an optimal code from among the candidate codes extracted by the candidate code extracting means, the points corresponding to the roles determined by the note role determining means are extracted from the point table A code detecting apparatus comprising: a candidate code that determines a candidate code that has the highest sum as a sum of points. Point table storage means for storing a point table in which points indicating musical importance are set for the roles of a plurality of notes characterizing the chord for each possible chord,
Performance data acquisition means for acquiring performance data;
Key information acquisition means for acquiring key information;
Code detection instruction means for instructing code detection at a predetermined code detection timing;
Candidate code extraction means for extracting a candidate code based on the key information acquired by the key information acquisition means when code detection is instructed by the code detection instruction means;
Pitch information extraction means for extracting pitch information considered valid at the chord detection timing from the performance data acquired by the performance data acquisition means when the chord detection is instructed by the chord detection instruction means;
When code detection is instructed by the code detection instructing means, for each candidate code extracted by the candidate code extracting means, each pitch information extracted by the pitch information extracting means has a plurality of characterizing codes. Note role discriminating means for discriminating which note role of the note has,
When the chord detection instruction is instructed by the chord detection instructing unit, the candidate role discriminating unit has determined that all pitch information extracted by the pitch information extracting unit has a role other than the root. Code detecting means for detecting an optimum code from among the candidate codes extracted by the candidate code extracting means, points corresponding to roles other than the root determined by the note role determining means A code detection apparatus comprising: a candidate code that is extracted from a table and summed, and a candidate code having the highest sum is determined as an optimal code. For each chord that can be a candidate, a point table that stores a point table in which points indicating musical importance are set for the roles of multiple notes that characterize the chord, and points for the root role are set low for any chord A computer having storage means and functioning as a code detection device,
A performance data acquisition step for acquiring performance data;
Key information acquisition step for acquiring key information;
A code detection instruction step for instructing code detection at a predetermined code detection timing;
A candidate code extraction step of extracting a candidate code based on the key information acquired in the key information acquisition step when code detection is instructed in the code detection instruction step;
When pitch detection is instructed in the chord detection instruction step, pitch information extraction step for extracting pitch information regarded as valid at the chord detection timing from the performance data acquired in the performance data acquisition step;
When chord detection is instructed in the chord detection instructing step, for each candidate code extracted in the candidate chord extraction step, each pitch information extracted in the pitch information extracting step has a plurality of characterizing codes. A note role determining step for determining which of the notes has a role;
When the chord detection is instructed in the chord detection instructing step, the candidate chord determined in the note role discriminating step that all the pitch information extracted in the pitch information extracting step has a role other than the root A code detecting step for detecting an optimum code from among the candidate codes extracted in the candidate code extracting step, and extracting points corresponding to the roles determined in the note role determining step from the point table A code detection program for causing a computer to execute a procedure consisting of determining a candidate code that has the highest sum as a sum of points, and determining an optimal code. A computer having a point table storing a point table in which points indicating musical importance are set for the roles of a plurality of notes characterizing a chord for each possible chord, and serving as a chord detection device ,
A performance data acquisition step for acquiring performance data;
Key information acquisition step for acquiring key information;
A code detection instruction step for instructing code detection at a predetermined code detection timing;
A candidate code extraction step of extracting a candidate code based on the key information acquired in the key information acquisition step when code detection is instructed in the code detection instruction step;
When pitch detection is instructed in the chord detection instruction step, pitch information extraction step for extracting pitch information regarded as valid at the chord detection timing from the performance data acquired in the performance data acquisition step;
When chord detection is instructed in the chord detection instructing step, for each candidate code extracted in the candidate chord extraction step, each pitch information extracted in the pitch information extracting step has a plurality of characterizing codes. A note role determining step for determining which of the notes has a role;
When the chord detection is instructed in the chord detection instructing step, the candidate chord determined in the note role discriminating step that all the pitch information extracted in the pitch information extracting step has a role other than the root A code detection step for detecting an optimum code from among the candidate codes extracted in the candidate code extraction step, points corresponding to roles other than the root determined in the note role determination step A code detection program for causing a computer to execute a procedure comprising: extracting from a table and summing them, and determining a candidate code having the highest summed point value as an optimal code.

Images