JP2017173644A - Musical performance analyzing device and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently detect a bow change action from an acoustic signal of a bowed stringed instrument.SOLUTION: An acoustic signal of a bowed stringed instrument is acquired, and a signal component (low-frequency noise signal component) outside the register of the object bowed stringed instrument is extracted from the acoustic signal. The bowed stringed instrument generates pulsed noise during the bow change (up-bow or down-bow) action. Such noise includes components outside the original register of the bowed stringed instrument. For the purpose, the low-frequency noise signal component is extracted from the acoustic signal and when the level thereof is equal to or higher than a predetermined threshold, the generation of the pulsed noise in the bow change action is detected. Thus, bow action timing is detected. Further, since the down-bow action is larger in sound volume than the up-bow action, the down-bow action is estimated when the sound volume of the acoustic signal at current bow action timing is a predetermined first threshold larger than the sound volume of the acoustic signal at last bow action timing, and the up-bow action is estimated when the sound volume is a predetermined second threshold smaller.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a performance analysis apparatus for analyzing a bowing state in a performance of a bowed instrument from an acoustic signal including a performance sound of the bowed instrument such as a violin, viola, cello, and contrabass. Regarding the program.

  In the performance of a bowed instrument such as a violin, it is required to perform the bowing order (up / down) accurately. For example, in a violin performance lesson, it is an important factor to evaluate whether or not the bowing order is correctly performed. Such bowing evaluation can be performed, for example, by visually confirming a performance operation performed by the performer, but it is preferable that it can be automatically performed without direct visual recognition by a human. Therefore, the present invention intends to provide a technique capable of directly analyzing the bowing state in the performance of the bowed instrument from the acoustic signal of the performance sound of the bowed instrument.

  By the way, various techniques related to bowing of a bowed instrument such as a violin are known. For example, in Patent Document 1 below, in response to a real-time performance of a violin, the stroke speed, pressure, and pronunciation point (position on the string where the bow contacts) detected by the player are detected using a sensor. It has been shown to produce an electrical signal indicative of the result. However, this cannot analyze the bowing state of the bowed instrument from the acoustic signal of the performance sound. In the following Patent Document 2, a bow moving speed is calculated from a volume value (velocity value) in MIDI standard performance data, and a bow return position is detected using the calculated value (specifically, the calculated moving speed). The bow trajectory is calculated on the basis of this, and the trajectory is compared with a parameter indicating the length of the bow, thereby detecting the folding position of the bow and obtaining this time). This is a technique intended to add control data corresponding to the bowing state to the performance data of the MIDI standard, and this is also not capable of analyzing the bowing state of a bowed instrument from the acoustic signal of the performance sound. Absent. Further, since the bow folding position is detected based on calculating the moving speed of the bow from the volume value, it is not suitable for quickly detecting the bow folding.

  Furthermore, in Patent Document 3 below, a fixed point which is a bowing point for preventing bowing (bowing) from being changed in the extraction of the bowing pattern is input and fixed to the note number of the electronic musical score data. It is shown that a bowing pattern is determined according to the points, extracted as a bowing pattern, and a bowing score with the extracted bowing pattern is output. However, this also cannot analyze the bowing state of the bowed instrument from the acoustic signal of the performance sound. In Patent Document 4 below, a performance sound of a plucked string instrument such as a guitar is converted into an electrical signal by a microphone, and a plurality of strings are compared by comparing the electrical signal of the performance sound with a predetermined evaluation standard. It is shown to detect and evaluate that a stroke performance that makes a stroke of 1 is performed. This also cannot analyze the bowing state of the bowed instrument from the acoustic signal of the performance sound.

  In the following Patent Document 5, a musical sound control device for an electronic musical instrument suitable for simulating a bowed musical instrument that performs using a movable performance member such as a bow is shown, and the string equivalent member and the bow are rubbed. Thus, a musical tone control signal of bow pressure and bow speed is generated by filtering the frictional sound generated in real time, and the bowed instrument simulation sound is controlled by the musical tone control signal. This is a technique for simulating a bowed instrument sound like a silent violin and cannot analyze the bowed state of the bowed instrument from the acoustic signal of the performance sound.

Japanese Patent Laid-Open No. 05-127589 JP 2001-159892 A JP 2009-265516 A JP 2011-069900 A JP 05-165465 A

  The present invention has been made in view of the above-described points, and it is an object of the present invention to provide a performance analysis apparatus and program for analyzing a bowing state in the performance of a bowed instrument from the acoustic signal of the bowed instrument. The purpose is to enable efficient detection of the return operation.

  The performance analysis apparatus according to the present invention includes an acquisition unit that acquires an acoustic signal, an extraction unit that extracts a signal component outside the range of the target bowed instrument from the acoustic signal, and a bow operation timing based on the level of the extracted signal component And a detecting unit for detecting.

  In a bowed instrument, pulsing noise is generated when the bow is returned. Such noise includes a component outside the range of the bowed instrument (for example, a component lower than the original range of the instrument). Therefore, a signal component outside the range of the bowed instrument is extracted from the acoustic signal of the performance sound of the bowed instrument, and a bow is returned based on the level of the signal component (for example, determining that the level is equal to or higher than a predetermined threshold). It is possible to detect the occurrence of pulse noise when the operation is performed. Thereby, the bow operation timing (bow return operation timing) can be detected.

  The present invention can be implemented and configured not only as an apparatus invention, but also as a program invention that causes a computer to execute the steps of realizing the functions of the performance analysis apparatus.

  According to the present invention, since the bow operation timing is detected based on a specific sound range component in the acquired acoustic signal, no complicated processing is required, and it is possible to efficiently detect the bow return operation. Has an effect.

The conceptual block diagram explaining the structural example of the performance analyzer which concerns on one Embodiment of this invention. (A) shows an example of the acquired acoustic signal by a volume envelope, (b) is a figure which shows an example of the low frequency noise signal outside the sound range of the target bowed instrument. The block diagram which shows the electrical hardware structural example in the case of comprising a performance analyzer using a computer. The flowchart which shows the example of a bowing direction estimation process. The flowchart which shows the example of evaluation and a display process. The figure which shows the example of a display according to the evaluation and display process of FIG.

  FIG. 1 is a conceptual block diagram illustrating a configuration example of a performance analysis apparatus according to an embodiment. The performance analysis apparatus 100 functions to analyze a bowing state (bow operation timing, that is, bow return timing, bowing direction, etc.) from an acoustic signal generated according to the performance of the bowed instrument. It can be used for any of various purposes, such as for the purpose of learning the playing method of this or for the purpose of evaluating the performance of a bowed instrument. The performance analysis apparatus 100 is broadly divided into an acquisition unit 10, an extraction unit 11, a detection unit 12, an estimation unit 13, an evaluation unit 14, a sound range setting unit 15, and a display unit 16. The performance analysis apparatus 100 may be configured by any computer device capable of executing operations of each unit (various processes for analyzing an audio signal described later) such as a general-purpose personal computer, or may be capable of executing operations of each unit. It may consist of a dedicated hardware device (such as an integrated circuit) configured as described above.

  The acquisition unit 10 acquires an acoustic signal AS generated in accordance with the performance of the bowed instrument as an analysis target. The acquisition unit 10 may be configured to acquire the acoustic signal AS by acquiring the user's musical instrument performance sound in real time through a sound collection unit such as a microphone, for example, and performing digital conversion, or The recorded data may be acquired from a recording medium in which the data of the musical instrument performance sound of the user is recorded, or the acoustic signal AS may be acquired from a remote place via a communication network. In that case, the encoding format of the acoustic signal AS acquired from the outside is not limited to the PCM format and may be data compressed in an appropriate compression format, and the acquisition unit 10 decodes the acoustic compression data as necessary. It may have a function. The acquired acoustic signal AS is appropriately buffered and stored in a FIFO or RAM, the volume envelope of which is detected in time series, and temporarily stored for use in the bow estimation process described later. FIG. 2A shows an example of the acoustic signal AS acquired by the acquisition unit 10 using a volume envelope.

  The extraction unit 11 extracts signal components outside the range of the bowed musical instrument to be analyzed from the acquired acoustic signal. The reason for extracting the signal component outside the range of the bowed instrument in this way is to exclude the signal component of the regular performance sound based on the vibration of the string caused by the bow operation (that is, the signal component within the range of the target bowed instrument) It is intended to extract friction noise during bow turning operation. For example, if the bowed instrument to be analyzed is a violin, the violin has a pitch range G3 to D # 7, and therefore belongs to an arbitrary band other than the band including the frequency component of the pitch range including the harmonic component. Extract signal components. In general, a stringed instrument sound includes harmonic components up to a considerably high frequency range, so it is preferable to extract a signal component on the low frequency side as a signal component outside the sound range of the target stringed musical instrument. As an example, when the stringed musical instrument to be analyzed is a violin, the extraction unit 11 uses, for example, a low-frequency bandpass filter with a band of about 10 Hz to 100 Hz (or a low-pass filter with a high frequency cutoff frequency of about 100 Hz). The signal component may be extracted. Of course, the low frequency band extracted by the low band band pass filter (low pass filter) is variably set according to the sound range of the target stringed musical instrument. For example, when the analysis target stringed instrument is a viola, the pass band of the low-frequency bandpass filter (low-pass filter) in the extraction unit 11 extracts a signal component on the lower frequency side than the high-frequency cutoff frequency lower than that of the violin. Is set as follows. In addition, when the analyzed stringed instrument is a cello or a contrabass, a lower high-frequency cut-off frequency corresponding to each is set, and a signal component on the low-frequency side is extracted from each high-frequency cut-off frequency. The

  FIG. 2B shows an example of the low-frequency noise signal outside the target bowed instrument musical range extracted by the extraction unit 11 corresponding to the acoustic signal of FIG. A portion where the low-frequency noise signal shows a high level in a spike shape indicates a portion where significant friction noise is generated during the bow turning operation. Based on the level of the extracted signal component outside the musical instrument sound range (low-frequency noise signal), the detection unit 12 is the timing when the bow return operation is performed (bow operation timing) when the level exceeds a predetermined threshold. Detected as t1, t2, t3,. The bow operation timing detection information BD indicating the bow operation timings t1, t2, t3,... Detected from the acoustic signal in this way can be used for various purposes. For example, as described below, it is used in the estimation unit 13 to estimate the bowing direction. Alternatively, the signal can be appropriately used in the other use device 17 as a signal indicating the rising of each performance sound (note) included in the acoustic signal AS.

  The estimation unit 13 estimates the bowing direction based on the bow operation timing detection information BD indicating the bow operation timing detected by the detection unit 12. Since the standard bowing of bowed instruments consists of alternating up and down bow operations, once the initial bow direction is specified for at least the appropriate partial performance section, the bow operation is performed thereafter. By estimating that the bowing direction changes at each timing, the bowing direction can be estimated based only on the bow operation timing detection information BD.

  A more accurate method for estimating the bowing direction is to take into account the volume of the acoustic signal AS of the performance sound. Since it is known that the sound of the lower bow sound is larger than that of the raised bow when operated with the same level of force, in one embodiment, the estimation unit 13 performs the adjacent bow operation timing. The arching direction at each detected arch operation timing may be estimated based on the mutual relationship between the volume levels of the acoustic signal AS in each section sandwiched between (ie, the mutual relationship between the volume levels of adjacent sections). . More specifically, a certain arch operation timing detected by the detection unit 12 (assuming this is called the first arch operation timing; for example, t2 in FIG. 2B) is a section (assuming this is the first section). The volume of the acoustic signal AS at the point immediately before the bow operation timing (assuming this is called the second bow operation timing; for example, t1 in FIG. ) Is greater than the volume of the acoustic signal AS and the volume difference is greater than a predetermined first threshold value, the first bow direction (lowering bow) is estimated, and the volume of the acoustic signal AS at the first bow operation timing is estimated. Is smaller than the volume of the second bow operation timing acoustic signal AS and the volume difference is smaller than a predetermined second threshold, the second bowing direction (raised bow) is estimated. Good.

In FIG. 2, an example of the bowing direction estimated by the combination of the bow operation timings t1, t2, t3,. ing. D indicates a lowering bow, and U indicates a raising bow. For example, the volume of the sound signal AS ₂ in the section that starts a certain arch operation timing t2 that has been detected, a second predetermined than the volume of the sound signal AS ₁ in a section that starts the bow operation timing t1 immediately before Since it is smaller than the threshold value, the bowing direction is estimated to be the raising bow U. Conversely, the volume of the acoustic signal AS ₁ in a section starting from a certain bow operation timing t1 is more than a predetermined first threshold value than the volume of the acoustic signal AS ₂ in a section starting from the immediately following bow operation timing t2. Since it is large, the bowing direction can be estimated as the down bow D. Hereinafter, similarly, the volume of the acoustic signal AS ₃ in a section starting from a certain bow operation timing t3 is a predetermined first volume higher than the volume of the acoustic signal AS ₂ in a section starting from the immediately preceding bow operation timing t2. Since it is larger than the threshold value, the bowing direction is estimated to be the lowering bow D. Note that the magnitude of the volume can be determined by comparing the maximum values of the respective volume envelopes, or may be determined by an average value instead of the maximum value. These threshold values may be determined as appropriate.

  Note that the estimating unit 13 is not limited to estimating the raising / lowering of the bow for each sound, but may be configured to estimate the alternating raising / lowering of the bow in the tremolo performance in one sound, or in the slur performance You may comprise so that the repetition of the bow return operation | movement to the same direction may be estimated. In this case, for example, the values of the first threshold value and / or the second threshold value are appropriately set according to the estimation target performance method such as tremolo or slur.

  The display unit 14 is a device that visually presents information indicating the bowing direction estimated by the estimation unit 13. When the estimated bowing direction is visually presented, any display form may be employed. For example, appropriate icons (for example, U and D) indicating the bow direction may be simply arranged and displayed in chronological order, or each note on the musical score display of the music played by the acquired acoustic signal AS. An icon indicating the estimated bowing direction may be displayed in association with. This display is not limited to the display display, but may be a print output by a printer. Note that the information indicating the estimated bowing direction is not limited to a visible method, and may be presented audibly by a notification sound or the like. Further, information indicating the estimated bowing direction may be recorded on a recording medium, and later read from the recording medium and presented visually or audibly. In this way, visually or audibly presenting information indicating the estimated bowing direction is, for example, whether the bowing is appropriate based on the acoustic signal AS played by the student in the practice of a bowed instrument. Of course, it is useful not only for teachers to evaluate, but also for students or performers themselves to check if their bow is appropriate.

  The evaluation unit 15 compares the information indicating the exemplary bow direction with respect to the music played by the acquired acoustic signal AS by comparing the information indicating the bow direction estimated by the estimation unit 13 with the acquired information. It is configured to evaluate the bow in the acoustic signal AS. This evaluation result can be presented to the user (teacher, student, performer, etc.) via the display unit 14. Any display form of the evaluation result can be adopted. For example, the score of the music played by the acquired acoustic signal AS is displayed on the display screen, and an icon indicating an evaluation result corresponding to each note on the score (an icon indicating that the bow was correct) An icon indicating that the bow was wrong) may be displayed. Or you may make it show the score which scored the bow based on the evaluation result. The evaluation result by the evaluation unit 15 may be accumulated and stored in a recording medium for each user (student or player). By accumulating and storing the evaluation results for each individual user (student or performer), it is possible to statistically elucidate the points on the musical score, etc. that are likely to be mistaken for bowing or bowing for each student or performer. In addition, it is possible to statistically elucidate a portion on the score where the bowing is easy to be mistaken or a point on the score which is difficult to be mistaken for the entire student or performer group.

  Note that the evaluation unit 15 can use the music database 20 for the evaluation of such a bow. The music database 20 stores and stores musical score data of a large number of music. The evaluation unit 15 accesses the music database 20 to acquire the score data of the music played by the acquired acoustic signal AS, and information indicating an exemplary bow direction regarding the music based on the acquired score data Get. If the musical score data stored in the music database 20 includes information indicating the bowing direction (bowing information), the information may be used as it is as information indicating the exemplary bowing direction. If the musical score data stored in the music database 20 does not include bowing information, a normal bowing rule (for example, alternately performing a lowering bow and a raising bow, returning a bow at a sound break, bar line, The sound immediately after is basically played with a bow, and the default bowing information is automatically associated with each note in the song based on the same note and the bow in the case of slurs and ties. May be generated and used as information indicating the model's bow direction. Note that even for musical score data including bowing information, only the main notes (notes for which the bowing direction is to be specified) are specified without presenting bowing information for all notes in the score. Many of them present bowing information. In such a case, the default bowing information may be automatically generated for notes lacking bowing information in order to specify bowing information for all notes in the score. . That is, the bowing information is adopted for the notes for which specific bowing information is clearly shown in the score data, and default bowing information is automatically generated for the other notes according to the normal bowing rule. The combination is used as information indicating the exemplary bow direction of the musical composition.

  The automatically generated default bowing information (information indicating the model bowing direction) may be stored in a memory dedicated to the user, or the user may rewrite (update) the music database 20. ) May be stored in the music database 20 if it is authorized. Also, it may be possible to share or rewrite the default bow information created by each user among multiple users. For example, such shared bow information may be stored and managed on the cloud. May be.

  The sound range setting unit 16 identifies the type of the target stringed instrument with respect to the acoustic signal AS acquired by the acquisition unit 10, and sets the sound range of the signal component to be extracted by the extraction unit 11 according to the identified instrument type. It is configured as follows. The identification of the target bowed instrument type in the range setting unit 16 may be performed in accordance with the type input operation (selection operation) of the target bowed instrument by the user, or the acoustic signal acquired by the acquisition unit 10. The type of the target stringed instrument may be automatically identified based on the analysis of the AS tone color and tone range. In the extraction unit 11, the pass band of the low-frequency band pass filter (low-pass filter) is variably set to a predetermined band lower than the lowest sound of the target bowed instrument according to the setting by the sound range setting unit 16.

  FIG. 3 is a block diagram showing an example of an electrical configuration when a computer is used as hardware of the performance analysis apparatus 100 of FIG. The performance analysis apparatus 100 includes a microprocessor unit (CPU) 101, a memory 102, an operation device 103, a display device 104, an audio interface (“audio I / F”) 105, a communication interface (“communication I / F”) 106, and the like. including. The CPU 101 executes various programs stored in the memory 102 and controls the overall operation of the performance analysis apparatus 100. The memory 102 includes a ROM, a RAM, and an external storage device. The external storage device includes an appropriate recording medium such as a magnetic disk, an optical disk, or a flash memory.

  The operation device 103 includes an operation input device such as a mouse and a keyboard and a mechanism for detecting the operation input. The display device 104 includes a display and a mechanism for controlling display on the display.

  The audio I / F 105 includes an input terminal for an acoustic signal (audio signal), an output terminal for the acoustic signal, an analog-digital converter, and a digital-analog converter. The performance analysis apparatus 100 can acquire an acoustic signal AS generated by real-time performance of a user (student or performer) 's bowed instrument via a microphone and an audio I / F 105 (not shown). In that case, the microphone and the audio I / F 105 constitute the acquisition unit 10.

  The communication I / F 106 includes an Ethernet (registered trademark) interface, a USB interface (detachable storage medium interface), and the like. The performance analysis apparatus 100 can be connected to a communication network such as the Internet via the communication I / F 106 to communicate with a remote place. The performance analysis apparatus 100 can acquire an acoustic signal AS generated by real-time performance of a musical instrument of a remote user (student or player) or an already recorded acoustic signal AS via the communication I / F 106. In that case, the communication I / F 106 constitutes the acquisition unit 10.

  FIG. 4 is a flowchart schematically showing an example of the bow direction estimation process including a software program that is non-transitoryly stored in the memory 102 and can be executed by the CPU 101.

  In step S1, the CPU 101 acquires the acoustic signal AS to be analyzed (operation of the acquisition unit 10 in FIG. 1). As an example, the CPU 101 acquires the generated acoustic signal via the audio I / F 104 in substantially real time and stores it in a buffer.

  In step S <b> 2, the CPU 101 selects an acoustic signal having a predetermined time length from the buffered acoustic signal AS as a processing target in order of time series.

  In step S <b> 3, the CPU 101 extracts a signal component (low frequency noise signal component) outside the range of the target bowed instrument from the acoustic signal having a predetermined time length selected as the processing target. This corresponds to the operation of the extraction unit 11 in FIG. 1 and includes applying a low-frequency bandpass filter (low-pass filter) to the acoustic signal as described above.

  In step S4, the CPU 101 detects a pulse having a level equal to or higher than a predetermined threshold from the extracted noise signal component, detects this timing as a bow operation timing, and information indicating the detected bow operation timing (bow operation timing detection information). BD) is stored. This corresponds to the operation of the detection unit 12 in FIG.

  In step S5, the CPU 101 divides the acoustic signal having the predetermined time length selected as the processing target into a plurality of sections at the detected bow operation timing. In step S6, the CPU 101 compares the volume with the immediately preceding section for each section divided by the detected bow operation timing. If the volume is higher than the immediately preceding section (the volume difference is the predetermined value). If the volume is lower than the immediately preceding section (if the volume difference is smaller than the predetermined second threshold), it is estimated to be a raised bow (U). The estimation result is stored in association with the bow operation timing detection information BD as information indicating the bowing direction (bowing estimation information U / D). This corresponds to the operation of the estimation unit 13 in FIG.

  In step S7, the CPU 101 determines whether the estimation in step S6 has been completed for all the sections related to the acoustic signal having the predetermined time length selected as the processing target. If NO, the process in step S6 is repeated. When the estimation in step S6 is completed for all the sections, the process goes to step S8 to determine whether the processing has been completed for all of the acquired acoustic signals AS. If NO, the process returns to step S2. In step S2, the earliest predetermined time length of the acoustic signal AS is selected as a processing target. Thereafter, the processing of steps S3 to S8 is repeated for the acoustic signal having a predetermined time length newly selected as the processing target. If the processing is completed for all the acquired acoustic signals AS, the processing in FIG. 4 is terminated.

  FIG. 5 is a flowchart schematically showing an example of an evaluation and display process including a software program that is temporarily stored in the memory 102 and can be executed by the CPU 101. This evaluation and display process may be performed concurrently with the process of FIG. 4 or may be performed at another time. 5 corresponds to the operations of the display unit 14 and the evaluation unit 15 in FIG.

  In step S11, the CPU 101 acquires score data of the music played by the acquired acoustic signal AS (for example, acquired from the music database 20 of FIG. 1), and the screen of the display device 104 based on the score data. Display the score above. For reference, an example of the displayed score is partially shown in FIG.

  In step S12, the CPU 101 determines whether bow information is included in the acquired musical score data. If the bowing information is not included, or if only a part is included, the process proceeds to step S13, and as described above, the normal bowing rule (for example, a sound in which a lowering bow and a raising bow are alternately performed) It responds to each note in the song based on the same note and the bow in the case of slurs and ties, etc. Then, bowing information is automatically generated and stored. For example, in FIG. 6A, a bowing symbol for instructing a raising bow is written at a note position indicated by a reference symbol B1, and a bowing symbol for instructing a lowering bow is indicated at a note location indicated by reference numerals B2 and B3. . In step S13, model bow information is generated according to a normal bow rule for other note locations. An example of the model bow information generated corresponding to FIG. 6A is shown in FIG. In FIG. 6 (d), the up bow and the down bow are shown using known music symbols.

  In step S14, the CPU 101 acquires the bow operation timing detection information BD and the bowing estimation information U / D generated (stored) in the processing of FIG.

  In step S15, the CPU 101 displays an appropriate icon indicating the detected bow operation timing on the screen of the display device 104 based on the acquired bow operation timing detection information BD, and also acquires the acquired bowing estimation information U. Based on / D, an appropriate icon indicating the estimated bowing direction is displayed on the screen of the display device 104. FIG. 6B shows an icon display example of the detected bow operation timing. In this example, the icon is displayed as a pulse figure. FIG. 6C shows an example of icon display indicating the estimated bowing direction (that is, the bowing state in the acoustic signal AS). In this example, “U” indicating a raising bow and a lowering bow are indicated. An icon consisting of the letter “D” is displayed.

  In step S16, based on the acquired bow operation timing detection information BD and bow estimation information U / D, the CPU 101 performs model bow information at the performance (pronunciation) timing indicated by the information BD and the corresponding bow estimation. The information U / D is compared, and an evaluation result is generated, displayed, and stored. FIG. 6C shows an example of an icon indicating the evaluation result. That is, when the bowing state in the acoustic signal AS shown in FIG. 6 (c) is compared with the exemplary bowing information shown in FIG. 6 (d), the second beat and the third beat of the second bar in the acoustic signal AS are compared. Incorrect bowing. Therefore, in FIG. 6C, a predetermined icon W indicating that the bow is not correct is displayed in combination with an icon (D or U) indicating the bow direction.

  In step S17, the CPU 101 determines whether to end the evaluation and display process. If NO, the CPU 101 returns to step S14, and the processes of steps S14 to S17 are repeated.

  In the above-described embodiment, the case where the signal component outside the range of the target bowed instrument extracted from the acoustic signal is a low-frequency noise signal component is not limited to this. You may make it extract a signal component.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the technical idea described in the claims and the specification and drawings. Deformation is possible. For example, the performance analysis apparatus 100 according to the present invention can be applied to a learning system in which a student terminal and a teacher terminal are connected via the Internet. In that case, the teacher's terminal (performance analysis apparatus 100) acquires the practice sound (acoustic signal AS) of the bowed instrument performance from the student's terminal on the Internet via the communication I / F 106, and uses the acquired practice sound as the acquired practice sound. Display performance analysis based on bow direction estimation and evaluation. Teachers can give guidance to students, such as commenting on them. In that case, the teacher's terminal (performance analysis apparatus 100) may be configured to simultaneously acquire a plurality of acoustic signals AS and to analyze them simultaneously by time division processing or parallel processing. Or, conversely, the student terminal (performance analysis apparatus 100) acquires musical instrument performance sounds (examples) from the teacher terminal on the Internet via the communication I / F 106, and the acquired performance sounds (examples). ) Based performance analysis (bowing direction estimation and evaluation) may be displayed. The student can perform effective practice by learning the characteristics of the performance based on the display or comparing with the performance analysis result of the student. Of course, each student's terminal (performance analysis apparatus 100) may be configured to simultaneously acquire a plurality of acoustic signals AS and analyze them simultaneously by time-division processing or parallel processing.

  As another example, a plurality of users' terminals (performance analysis apparatus 100) are connected to each other by wire or wireless so that each other's information (including the bowing information as an analysis result) can be exchanged. The information may be confirmed by other users. For example, when a plurality of users are playing their own bowed instruments in an orchestra or the like, their own bowing information is sent from their own terminal (performance analysis apparatus 100) to another user's terminal (performance analysis apparatus 100). By transmitting to, it is possible to use it so that appropriate notification can be performed when the bowing direction is different among users. Further, as described above, bowing information of a plurality of users exchanged by wire or wireless may be centrally managed in an apparatus for an administrator (instructor or teacher), thereby making a mistake in bowing. It is possible to statistically elucidate places on the musical score that are easy or difficult to mistake, and places where other specific users have earlier / slower performance timing than other users. Such an elucidated result can be expected to be able to be notified to the user and the instructor (teacher) in real time during the practice performance. In an orchestra or the like, it is important that the bow timing and the bow direction of all players in the part are aligned for each performance part. Therefore, by applying the present invention, appropriate assist can be performed.

  Moreover, the performance analysis apparatus 100 of this invention may be comprised so that at least one part function of each part 10-16 may be distributed and performed by one or more computer apparatuses on a network. The present invention also includes a step of acquiring an acoustic signal in a computer, a step of extracting a signal component outside the range of the target bowed instrument from the acoustic signal, and detecting a bow operation timing based on the level of the extracted signal component. And an invention of a program for executing the step. The present invention also includes a step of acquiring an acoustic signal, a step of extracting a signal component outside the range of the target bowed instrument from the acoustic signal, a step of detecting a bow operation timing based on the level of the extracted signal component, May be configured as a method invention implemented by a computer or processor.

DESCRIPTION OF SYMBOLS 100 Performance analyzer, 10 Acquisition part, 11 Extraction part, 12 Detection part, 13 Estimation part, 14 Display part, 15 Evaluation part, 16 Sound range setting part, 101 Microprocessor unit (CPU), 102 Memory, 103 Operating device, 104 Display device, 105 audio interface, 106 communication interface.

Claims (10)

An acquisition unit for acquiring an acoustic signal;
An extraction unit for extracting a signal component outside the range of the target stringed instrument from the acoustic signal;
A performance analysis apparatus comprising: a detection unit that detects a bow operation timing based on the level of the extracted signal component. 2. The performance according to claim 1, further comprising an estimation unit configured to estimate a bowing direction at each detected bow operation timing based on a mutual relationship between sound volumes of the acoustic signals in each section sandwiched between adjacent bow operation timings. Analysis equipment.   The estimation unit is configured such that the volume of the acoustic signal in the first section starting from the first bow operation timing is larger than the volume of the acoustic signal in the second section immediately before the first bow operation timing, and the volume difference is a predetermined first level. When larger than one threshold, the bowing direction at the first bow operation timing is estimated as the first bowing direction, while the volume of the acoustic signal in the first section is the volume of the acoustic signal in the second section. 3. The performance analysis apparatus according to claim 2, wherein the bowing direction at the first bow operation timing is estimated as the second bowing direction when the volume difference is smaller than the predetermined second threshold value.   The performance analysis apparatus according to claim 1, wherein the extraction unit includes a filter that extracts a signal component having a frequency lower than the sound range of the target stringed musical instrument.   The performance analyzer according to claim 1, further comprising a device that presents information indicating the detected bow operation timing or the estimated bow direction.   The evaluation part which evaluates the bow in the said acquired acoustic signal is further provided by comparing the information which shows the model bow direction regarding a certain music with the information which shows the said estimated bow direction. The performance analyzer in any one of thru | or 4.   The acoustic signal acquired by the acquisition unit further includes a sound range setting unit that identifies a type of the target stringed musical instrument and sets a sound range of the signal component to be extracted by the extraction unit according to the identified musical instrument type. Item 7. The performance analyzer according to any one of Items 1 to 6. The acquisition unit is configured to acquire a plurality of the acoustic signals by wire or wirelessly,
The extraction unit extracts the signal component for each acquired acoustic signal,
The performance analysis device according to claim 1, wherein the detection unit detects the bow operation timing for each of the acquired acoustic signals. A plurality of performance analyzers according to any one of claims 1 to 8,
A system configured to connect a plurality of the performance analysis apparatuses by wire or wirelessly to communicate information. On the computer,
Obtaining an acoustic signal;
Extracting a signal component outside the range of the target stringed instrument from the acoustic signal;
And a step of detecting a bow operation timing based on the level of the extracted signal component.

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