JP2010072595A - Beat location presumption system, method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a beat location presumption system, method, and program, which surely presumes a beat location in response to a large change in tempo while reducing the amount of calculation. <P>SOLUTION: The beat location presumption system 100 estimates the beat location of the data of a piece of music and is provided with: an initial setting section 101 that sets the first section of analysis; an analysis sections setting part 102 that sequentially sets the succeeding sections of analysis immediately succeeding the first section of analysis; a validation section setting part 103 that sets validation sections within the respective sections of analysis; a beat location detection part 110 that detects beat locations with respect to music data in the respective sections of analysis or validation sections; and a validation part 114 that validates whether the beat locations detected in the respective sections of analysis are identical with the beat locations detected in the respective validation sections within the respective sections of analysis. Thus, the presumption of beat locations is performed over the whole data of a piece of music from the results of the validations. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a beat position estimating apparatus, a beat position estimating method, and a beat position estimating program for estimating a beat position of music data.

  Conventionally, a technique for automatically extracting beat and tempo information from a music waveform signal is known. For example, the apparatus and method described in Patent Literature 1 sets a plurality of different estimation ranges for an input music signal, and integrates the tempo estimation for each estimation range and the tempo values of the plurality of estimation ranges. Thus, a tempo value that varies with time is obtained for the music data. In this way, it is possible to estimate the tempo of music data such that the tempo changes during the music. In addition, the methods described in Patent Documents 2 and 3 and Non-Patent Document 3 calculate a time-series power spectrum based on STFT or a feature amount corresponding to the music waveform signal obtained from PCM data, The beat position is estimated by using auto-correlation and cross-correlation.

Further, in the method described in Non-Patent Document 1, a so-called beat histogram is used as a feature amount as a rhythm feature amount. The beat histogram is calculated as a tempo statistic extracted from the time envelope and autocorrelation of the music acoustic signal in each frequency band. The method described in Non-Patent Document 2 performs beat estimation in real time based on the transition probability of onset (sound rise) chords of harmonic sounds and percussion instrument pattern information. A percussion instrument pattern is a combination of a bass drum in which energy is localized in a low frequency region of a spectrum and a snare drum in which energy is spread in a wide frequency region. Based on such percussion instrument pattern information, the beat position is estimated by using prior information that is generally known in terms of music.
JP 2003-263162 A JP 2002-116754 A JP 2007-33851 A G. Tzanetakis and P. Cook, “Musical genre classification of audio signals”, IEEE, Trans on Speech and Audio Processing, Vol. 10, No. 5, pp.293-302 Goto.M, “An audio-based real-time beat tracking system for music with or without drum-sounds.”, Journal of New Music Research, June 2001, Vol.30, No.2, pp.159-171 Miguel Alonso, Bertrand David, and Gael Richard, “Tempo and beat estimation of music signals”, In Proc.ISMIR2004.

  Patent Document 1 describes a method capable of estimating tempo fluctuations in a time series by multi-stage analysis in order to enable tempo estimation of music data such that the tempo changes in the middle of music. Tempo estimation with a large signal width is applied in the first stage, and tempo estimation is performed in the second stage for the section set based on the tempo estimated in the first stage. However, in the multistage analysis as described above, since the amount of analysis becomes enormous, real-time estimation is difficult. Further, as described in Patent Document 1, the techniques described in Patent Documents 2 and 3 and Non-Patent Documents 1 to 3 cannot cope with a large tempo change.

  The present invention has been made in view of such circumstances, and is capable of estimating a beat position accurately in response to a significant change in tempo while reducing the amount of calculation, and a beat position estimation method and a beat position estimation method. An object is to provide a position estimation program.

  (1) In order to achieve the above object, the beat position estimating device of the present invention is a beat position estimating device for estimating the beat position of music data, and includes an initial setting unit for setting an initial analysis section, An analysis interval setting unit that sequentially sets analysis intervals subsequent to the analysis interval, a verification interval setting unit that sets a verification interval within each analysis interval, and beat positions of the music data of each analysis interval or verification interval are detected A beat position detection unit; and a verification unit that verifies whether or not the beat position detected in each analysis section matches the beat position detected in the verification section in each analysis section, and the verification The beat position is estimated over the entire music data based on the result. The beat position refers to the time of a beat that is periodically engraved on the time axis for the reproduction of music. Further, “over the whole music data” means the whole range of music for which estimation of the beat position is required, and does not necessarily mean all music.

  As described above, the beat position estimating apparatus according to the present invention sets the verification section in the analysis section and verifies whether the beat positions detected in both sections match each other. Based on the verification result, the beat position is estimated over the entire music data. Thereby, it is possible to accurately estimate the beat position with respect to the tempo variation existing in the music data. Further, it is not necessary to repeatedly analyze the entire music data over and over, compared to a conventional method that can cope with tempo fluctuations, and the amount of calculation can be reduced.

  (2) Moreover, the beat position estimation apparatus of the present invention is characterized in that the verification section setting unit sets a verification section based on the beat position detected in each analysis section. Thereby, verification with high accuracy can be performed efficiently.

  (3) Moreover, the beat position estimation apparatus of the present invention is characterized in that the analysis section setting unit sequentially sets analysis sections over the entire music data based on the verification result. As a result, it is possible to set an analysis interval suitable for detecting an accurate beat position efficiently.

  (4) Moreover, the beat position estimation apparatus of the present invention further includes a position determination unit that determines whether or not the start position of the analysis section is appropriate based on the detection result of the beat position for the analysis section. As a result, when the start position of the analysis section is inappropriate, the analysis section setting unit sets the next analysis section in which the start position is shifted. As described above, the beat position estimation apparatus of the present invention determines whether or not the start position of the analysis section is appropriate, and shifts the analysis section when it is not appropriate. As a result, for example, an analysis section can be set so as not to include a section where there is almost no sound or a section where narration is recorded, and an appropriate analysis section is set to detect an accurate beat position efficiently. be able to.

  (5) Further, in the beat position estimation device according to the present invention, when the analysis section setting unit, as a result of the verification, does not match the beat positions, the beat position detected in the verification section is used as a reference. It is characterized by setting the length and starting position of the analysis section. Thereby, for example, the length of the analysis section can be set based on the beat interval detected in the verification section, and the analysis section can be set using the beat position detected in the verification section as the start position.

  (6) Further, in the beat position estimation device of the present invention, when the analysis section setting unit does not match the beat positions as a result of the verification, a standard lowest beat is determined based on a beat position interval detected in the verification section. An interval longer than the interval is set to the length of the next analysis section. The standard minimum beat interval refers to the minimum beat interval derived from the upper limit of the tempo range of general music. Usually, the range of the tempo of general music is 50 BPM or more and 250 BPM or less. Therefore, since the beat interval at the upper limit of 250 BPM is 0.24 seconds, 0.24 seconds can be taken as the standard minimum beat interval. Thereby, a section including two or more beat positions detected in the verification section can be set as an analysis section, and an accurate beat position can be detected efficiently.

  (7) Further, in the beat position estimation device of the present invention, the analysis interval setting unit is detected in the analysis interval or the verification interval from the first beat position detected in the analysis interval set immediately before. It is characterized in that the next analysis section is set with the position shifted by one beat as the start position. Thereby, it is possible to set an analysis section that is shifted for each beat based on the detection result, and it is possible to accurately detect the beat position while considering the beat position.

  (8) Further, in the beat position estimation device of the present invention, the analysis interval setting unit is detected in the analysis interval or the verification interval from the last beat position detected in the analysis interval set immediately before. It is characterized in that the next analysis section is set with the position shifted by one beat as the start position. This makes it possible to set an analysis section that is shifted so that only the last beat of each analysis section overlaps based on the detection result, and it is possible to efficiently detect the beat position while considering the beat position. It becomes.

  (9) Further, in the beat position estimation device of the present invention, the analysis section setting unit sets a start position of the next analysis section so as not to overlap a section where the beat positions do not match as a result of the verification. It is a feature. As a result, it is possible to efficiently detect the beat position by skipping an irregular beat section or a section without a beat.

  (10) The beat position estimating apparatus of the present invention is further characterized by further comprising an integration unit that integrates the beat positions detected in each analysis section over the entire music data. Thereby, beat positions can be integrated and a more appropriate beat position can be estimated over the entire music data.

  (11) Further, the beat position estimation method of the present invention is a beat position estimation method for estimating the beat position of music data, and when the first analysis section is set, the analysis sections subsequent to the first analysis section are sequentially set. An analysis interval setting step, a verification interval setting step for setting a verification interval in each analysis interval, a beat position detection step for detecting a beat position for each analysis segment or music data in the verification interval, and each analysis interval Verifying whether or not the beat position detected in step 1 and the beat position detected in the verification section in each analysis section match, and in the verification section setting step, A verification section is set based on the detected beat position, and the analysis section setting step sequentially sets the analysis section over the entire music data based on the verification result. There. This makes it possible to accurately estimate the beat position in response to a significant change in tempo while reducing the amount of calculation.

  (12) The beat position estimation program of the present invention is a beat position estimation program for estimating the beat position of music data, and includes an initial setting process for setting a first analysis section and an analysis following the first analysis section. An analysis section setting process for sequentially setting sections, a verification section setting process for setting a verification section in each analysis section, a beat position detection process for detecting a beat position for music data in each analysis section or verification section, A verification process for verifying whether or not the beat position detected in each analysis section and the beat position detected in the verification section in each analysis section match, and the verification section setting process Then, a verification section is set based on the beat position detected in each analysis section, and in the analysis section setting process, the analysis section is sequentially set over the entire music data based on the verification result. It is characterized in Rukoto. This makes it possible to accurately estimate the beat position in response to a significant change in tempo while reducing the amount of calculation.

  According to the present invention, it is possible to accurately estimate a beat position with respect to a tempo change existing in music data. Further, it is not necessary to repeatedly analyze the entire music data over and over, compared to a conventional method that can cope with tempo fluctuations, and the amount of calculation can be reduced.

  Next, embodiments of the present invention will be described with reference to the drawings. In order to facilitate understanding of the description, the same reference numerals are given to the same components in the respective drawings, and duplicate descriptions are omitted.

(Configuration of beat position estimation device)
FIG. 1 is a block diagram showing a configuration of the beat position estimating apparatus 100. As shown in FIG. The beat position estimation apparatus 100 estimates the beat position of music data. Specifically, the beat position estimation apparatus 100 may be a content server that provides music data, or may be a mobile terminal such as a mobile phone or a mobile music player.

  As shown in FIG. 1, the beat position estimating apparatus 100 includes an initial setting unit 101, an analysis section setting unit 102, a verification section setting unit 103, a music database 106, a section extraction unit 107, a beat position detection unit 110, and a position determination unit 111. A recording unit 113, a verification unit 114, an integration unit 118, a basic beat position estimation unit 119, a beat information storage unit 120, and a meta information generation unit 121.

  The initial setting unit 101 sets an initial analysis section in order to extract a music data signal to be analyzed. The length of the first analysis section can be set on the basis of about 1.2 seconds, for example. About 1.2 seconds is a length that makes the beat interval the longest in consideration of the tempo range of a general music being 50 BPM or more and 250 BPM or less. Further, the start position of the first analysis section can be set to the start position of the music data signal. However, the start position is not limited to this. In the following description, the standard minimum beat interval is added to the length when setting the length of the analysis section and the start position unless otherwise specified. In addition, the start position is assumed to be a start position that is half the standard minimum beat interval. By setting a long analysis section in advance and shortening the analysis section according to the beat position detection status, the beat position can be estimated efficiently and accurately. When the beat position is estimated on the mobile terminal, problems such as memory limitations can be avoided by managing the target section to a section length that can be executed on the apparatus.

  The analysis interval setting unit 102 sequentially sets analysis intervals subsequent to the first analysis interval. The analysis section setting unit 102 sequentially sets a plurality of analysis sections over the entire music data based on the verification result. Based on the verification result, it is possible to set an analysis interval suitable for efficiently detecting an accurate beat position. The beat position estimation apparatus 100 determines whether or not the start position of the analysis section is appropriate. If the start position is not appropriate, the analysis section setting unit 102 shifts the analysis section. For example, the analysis section can be set so as not to include a section where there is no sound or a section where narrative is recorded.

  The analysis section setting unit 102 performs verification when the beat position does not match as a result of determining whether or not the beat position detected in the analysis section matches the beat position detected in the verification section by the verification unit 114. The length and start position of the next analysis section are set based on the beat position detected in the section. For example, the length of the analysis section can be set based on the beat interval detected in the verification section, and the analysis section can be set using the beat position detected in the verification section as the start position.

  Further, an interval longer than the standard minimum beat interval than the beat position interval detected in the verification interval may be set as the length of the next analysis interval. In that case, the analysis section is set with the start position being a position earlier than the target first beat position by half the standard minimum beat interval. Thereby, a section including at least two beat positions detected in the verification section can be set as an analysis section, and an accurate beat position can be detected efficiently. In this way, the beat position estimating apparatus 100 estimates the beat position over the entire music data based on the verification result. Thereby, it is possible to accurately estimate the beat position corresponding to the tempo change while reducing the calculation amount.

  The analysis interval setting unit 102 starts from a position shifted from the first beat position detected in the analysis interval set immediately before by one beat interval detected in the analysis interval or the verification interval. The next analysis interval may be set. Thereby, it is possible to set an analysis section that is shifted for each beat based on the detection result, and it is possible to accurately detect the beat position while considering the beat position.

  Further, the analysis section setting unit 102 starts from a position shifted from the last beat position detected in the analysis section set immediately before by one beat detected in the analysis section or the verification section. The next analysis interval may be set. This makes it possible to set an analysis section that is shifted so that only the last beat of each analysis section overlaps based on the detection result, and it is possible to efficiently detect the beat position while considering the beat position. It becomes.

  In addition, the analysis interval setting unit 102 sets the start position of the next analysis interval so that it does not overlap when there is an interval where beat positions detected in the analysis interval and the verification interval do not match as a result of the verification. May be. That is, the start position of the analysis section can be set by advancing (skipping) the section determined to be inappropriate. As a result, it is possible to efficiently detect a beat position while ignoring a section having an irregular beat or a section without a beat. Note that an analysis section having a predetermined length can be set for each predetermined interval without reflecting the verification result.

  The verification section setting unit 103 sets a verification section in each analysis section based on the beat position detected in each analysis section. For example, a section that is longer than the interval between adjacent beat positions (beat interval) by the standard minimum beat interval is preferably used as the verification section. Further, it may be the length of two beat intervals. The music database 106 stores music data that can be a target of beat position estimation. The music data is stored in a file format such as AAC.

  The section extraction unit 107 extracts music data of the set section. The section may be an analysis section or a verification section. Specifically, the music data stored in the music database 106 is called, and the music signal in the section for which the beat position is to be estimated is extracted. If the format of the music data is not suitable for analysis, the section extraction unit 107 performs conversion into a file format suitable for analysis.

  The beat position detection unit 110 detects the beat position of the music data in each analysis section or verification section extracted by the section extraction unit 107. Then, the detected beat position is treated as a temporary beat position. For example, beat position detection based on autocorrelation can be performed. Then, the beat position of the music data in the set analysis section is repeatedly detected, and the beat position of the music data in the detection section is also detected for each analysis section. The beat position detection process will be described later. The method for detecting the beat position is not limited to this method. At the stage of calculating the detection function (the function to be subjected to autocorrelation calculation, the same applies hereinafter), the band pass filter such as the low pass filter or the band pass filter such as the band pass filter is used. A filter may be applied.

  The position determination unit 111 determines whether the start position of the analysis section is appropriate based on the detection result of the beat position for the analysis section. For example, when the average volume of the analysis section is 50 db or less or when the correlation in the analysis section is low, the start position of the analysis section is determined to be inappropriate. As a result of the determination, if appropriate, the process shifts to setting of a verification section, and if inappropriate, the beat position estimation apparatus 100 resets the start position of the analysis section by the analysis section setting unit 102.

  The recording unit 113 records the detected beat position. Not only the detection results in the analysis interval but also the detection results in the verification interval are recorded. The recording unit 113 sequentially records the beat positions detected by the beat position detection unit 110 for each section. The recording unit 113 holds a detection result for each analysis section and detection section.

  The verification unit 114 verifies whether or not the beat position detected in each analysis section matches the beat position detected in the verification section in each analysis section. Matching means that the detected beat positions are within a predetermined error range. As the error range, the standard minimum beat interval or half thereof can be set. For example, determining whether there is any of the beat positions detected in the analysis section within the error range of each beat position detected in the verification section (when the time from the start of the music to each beat has elapsed) Verify by

  Further, it is determined whether or not each beat position detected in the analysis section has a beat position detected in the verification section within the error range, and each beat position detected in the verification section is included in the error range. It may be determined whether there is a beat position detected in the analysis section. By such processing, the verification unit 114 compares the detection result in the analysis section with the detection result in the verification section. When the beat positions match, the verification section 114 determines that the analysis section is appropriate. Is determined to be inappropriate.

  The integration unit 118 integrates the beat positions detected in each analysis section over the entire music data. This makes it possible to estimate a more appropriate beat position over the entire music data. For example, information on estimated beat positions in a plurality of set analysis sections can be accumulated based on a time series, and the accumulated number of beats estimated at each time point can be used as the likelihood of the beat. Note that the beat position detected by the beat position detection unit 110 without providing the integration unit 118 may be used as the estimation result.

  The basic beat position estimation unit 119 estimates the basic beat position over the entire music data from the integrated beat position. The basic beat position estimation unit 119 estimates a likely beat as an effective beat from the integrated beat position information obtained by the integration unit 118. The processing of integration and basic beat position estimation will be described later.

  The beat information storage unit 120 stores beat information that specifies beat positions estimated over the entire music data. The meta information generation unit 121 generates meta information that identifies beat positions estimated over the entire music data. Thus, the final analysis result can be output as meta information. Note that the beat position estimation apparatus 100 does not include the integration unit 118 and the basic beat position estimation unit 119, and the beat position detected by the beat position detection unit 110 can be a beat position estimated over the entire music. .

  The beat position estimation apparatus 100 controls each part by a control unit (not shown) and determines whether to end or continue the beat position detection. For example, when the beat position is detected over the entire target music data, it is determined to end, and when the beat position is not detected over the entire target music data, it is determined to continue. When the detection is not performed for the entire music data section, the control unit instructs the section extraction unit 107 to extract the music data of the next section.

  In this manner, the position of the analysis section and the length of the analysis section can be automatically set from the target music data. Note that the present invention is not limited to the above example, and it is also possible to calculate a detection function for music data in advance and set the first analysis section.

(Operation of beat position estimation device)
Next, the operation of the beat position estimating apparatus 100 will be described. FIG. 2 is a flowchart showing an example of a characteristic operation of the beat position estimating apparatus 100 according to the present invention. First, the beat position estimation apparatus 100 sets the first analysis section (step S1). Then, it is determined whether or not beat position detection and verification have been completed for all analysis sections (step S2). When the detection and verification of the beat positions are completed for all the analysis sections, the beats are integrated (step S3), the integrated beat positions are output as the estimated beat positions, and the process ends. On the other hand, if beat position detection and verification have not been completed for all analysis sections, the music data of the set analysis section is extracted (step S4).

  Then, the beat position is detected for the music data of the extracted analysis section (step S5). Next, it is determined whether or not the position of the analysis section is appropriate based on the detected beat position (step S6). If it is determined that the position of the analysis section is not appropriate, the analysis section is set by reflecting the determination result (step S7). If it is determined that the position of the analysis section is appropriate, the verification section is set (step S8), the music data of the verification section is extracted (step S9), and the beat position is detected for the music data (step S10). ).

  Next, it is determined (verified) whether or not the beat position detected in the analysis section matches the beat position detected in the verification section (step S11). If it is determined that the beat positions do not match, the process returns to step S7, and an analysis section reflecting the verification result is set. In this case, the length and position of the analysis section can be set based on the verification result. If the beat positions match, the matched beat position is recorded (step S12), the next analysis section is set (step S13), and the process returns to step S2.

(Analysis section setting and beat position detection)
FIGS. 3A to 3D are schematic diagrams illustrating setting of an analysis section, detection of a beat position in the analysis section, setting of a verification section, and detection of a beat position in the verification section, respectively. As shown in FIG. 3A, an analysis section 201 is first set for the music data that is the target of beat position estimation. Then, as shown in FIG. 3B, beat positions P1 to P3 are detected for the analysis section 201. Next, as shown in FIG. 3C, a verification section 301 that is slightly wider than the detected beat interval is set. Then, as shown in FIG. 3D, beat positions R1 and R2 are detected for the verification section 301. Verification processing is performed by determining whether or not the beat positions P1 to P3 detected for the analysis section 201 are within the error ranges of the beat positions R1 and R2. For example, if the first and second beat positions P1 and P2 in the analysis section shown in FIG. 3 do not match the first and second beat positions R1 and R2 in the verification section, it is determined to be inappropriate.

  In the example shown in FIG. 3, the verification section is set for the section including the first to second beats of the estimation result in the first analysis section. However, the verification section is not limited to this, and the third beat The form including up to the eyes, the section including only the second to third beats, or the section including all of the analysis sections can be set as the verification section. Also, a plurality of verification intervals may be set and verification may be performed for each verification interval.

(Beat position detection)
FIG. 4 is a flowchart showing beat position detection processing. The music data of the analysis section set as described above is extracted, the short-time Fourier transform is applied to the input waveform, and the spectrogram in the input waveform is calculated (step T1). A power function in time series is obtained from the spectrogram (step T2), a beat interval is calculated by an autocorrelation function (step T3), and a beat position is detected by calculating a beat position by a cross correlation function (step T4).

(Analysis section setting)
FIGS. 5A to 5C are schematic diagrams illustrating examples of setting analysis sections. The analysis section setting unit 102 sets the start position of the next analysis section by shifting the position of the analysis section. For example, as shown in FIG. 5A, the start position of the next analysis section 203 is set immediately after the end position of the immediately previous analysis section 202. Further, as shown in FIG. 5B, the next analysis section 204 may be set to overlap with the position of the immediately previous analysis section 202. Further, as shown in FIG. 5C, the next analysis interval 205 may be set by skipping the beat interval detected in the immediately previous analysis interval 202. In the analysis section setting method shown in FIG. 5B, the analysis section is shifted by the detected beat position interval using the detection result of the immediately preceding analysis section 202. The shift amount is preferably one beat (beat interval), but is not limited thereto.

(Integration and basic beat position estimation)
Next, integration and basic beat position estimation will be described. FIG. 6 is a schematic diagram showing the integration processing of the detected beat positions. For example, the integration unit 118 shifts the analysis interval by any of the methods shown in FIGS. 5A to 5C and adds detection results obtained in duplicate on each time series.

  As shown in FIG. 6, Beat_ (n) is a power function indicating the beat position detected by each analysis section. Integrated_Beat is the estimated beat position after integration. Integrated_Beat is obtained by accumulating detection results N (integer) at each beat position on the time series of Beat_ (n). In FIG. 6, the integrated beat position information is represented as a function Integrated_Beat. In addition, by multiplying Integrated_Beat by a window function such as a Hanning window, a peak detection result is obtained after performing smoothing or other processing, and a tempo (BPM) calculation is performed based on the peak interval. be able to. For example, only beats that are 1/2 or more of the maximum value in Integrated_Beat in FIG. 6 can be extracted and estimated as basic beat positions.

In estimating the beat position, when the detected beat positions are bI (1), bI (2),..., BI (m), the beat position is calculated using the following formula. You can also.

  Each process of the above beat position estimation can be performed by making a computer run a program. In the above embodiment, the verification result is reflected in the analysis interval. However, the analysis interval may be set regardless of the verification result. Even in that case, since the verification is performed by comparing the detected beat position in the analysis section and the detected beat position in the verification section, it is possible to improve the precision of the beat position.

It is a block diagram which shows the structure of the beat position estimation apparatus 100 which concerns on this invention. It is a flowchart which shows the characteristic operation | movement of the beat position estimation apparatus 100 which concerns on this invention. It is the schematic which shows the setting of (a) analysis section, (b) detection of the beat position in an analysis section, (c) setting of a verification section, and (d) detection of the beat position in a verification section. It is a flowchart which shows a beat position detection process. (A)-(c) It is the schematic which shows the example of a setting of an analysis area. It is the schematic which shows the integration process of the detected beat position.

Explanation of symbols

100 beat position estimation apparatus 101 initial setting section 102 analysis section setting section 103 verification section setting section 106 music database 107 section extraction section 110 beat position detection section 111 position determination section 113 recording section 114 verification section 118 integration section 119 basic beat position estimation section 120 beat information storage unit 121 meta information generation unit 201-205 analysis section 301 verification section P1-P3, R1, R2 beat position

Claims (12)

A beat position estimation device for estimating the beat position of music data,
An initial setting section for setting the first analysis section;
An analysis interval setting unit that sequentially sets analysis intervals subsequent to the first analysis interval;
A verification interval setting unit for setting a verification interval in each analysis interval;
A beat position detector for detecting a beat position for the music data of each analysis section or verification section;
A verification unit that verifies whether the beat position detected in each analysis section and the beat position detected in the verification section in each analysis section match,
A beat position estimating apparatus for estimating a beat position over the entire music data based on the verification result.   The beat position estimation device according to claim 1, wherein the verification section setting unit sets a verification section based on the beat positions detected in each analysis section.   The beat position estimation device according to claim 1 or 2, wherein the analysis section setting unit sequentially sets analysis sections over the entire music data based on the verification result. Based on the detection result of the beat position for the analysis section, further comprising a position determination unit for determining whether the start position of the analysis section is appropriate,
The analysis section setting unit sets a next analysis section in which the start position is shifted when the start position of the analysis section is inappropriate as a result of the determination. The beat position estimation apparatus according to any one of the above.   The analysis interval setting unit sets the length and start position of the next analysis interval based on the beat position detected in the verification interval when the beat positions do not match as a result of the verification. The beat position estimation apparatus according to any one of claims 1 to 4, wherein the beat position estimation apparatus is characterized in that   The analysis interval setting unit sets, as a length of the next analysis interval, an interval longer than the standard minimum beat interval than the interval of the beat positions detected in the verification interval when the beat positions do not match as a result of the verification. The beat position estimating apparatus according to claim 5, wherein   The analysis section setting unit starts from a position shifted by one beat from the beat interval detected in the analysis section or the verification section from the first beat position detected in the analysis section set immediately before. The beat position estimation apparatus according to any one of claims 1 to 6, wherein a next analysis section is set.   The analysis interval setting unit starts from a position shifted from the last beat position detected in the analysis interval set immediately before by one beat of the beat interval detected in the analysis interval or the verification interval. The beat position estimation apparatus according to any one of claims 1 to 7, wherein a next analysis section is set.   The analysis section setting unit sets a start position of the next analysis section so as not to overlap with a section where the beat positions do not match as a result of the verification. The beat position estimating apparatus described.   The beat position estimating apparatus according to any one of claims 1 to 9, further comprising an integration unit that integrates beat positions detected in each analysis section over the entire music data. A beat position estimation method for estimating the beat position of music data,
If you set the first analysis interval,
An analysis interval setting step for sequentially setting analysis intervals subsequent to the first analysis interval;
A verification interval setting step for setting a verification interval in each analysis interval;
A beat position detecting step of detecting a beat position for the music data of each analysis section or verification section;
Verifying whether the beat positions detected in each analysis section and the beat positions detected in the verification section within each analysis section match,
In the verification interval setting step, based on the beat position detected in each analysis interval, a verification interval is set,
In the analysis section setting step, a beat position estimation method, wherein analysis sections are sequentially set over the entire music data based on the verification result. A beat position estimation program for estimating the beat position of music data,
An initial setting process for setting the first analysis interval;
An analysis interval setting process for sequentially setting analysis intervals subsequent to the first analysis interval;
A verification interval setting process for setting a verification interval in each analysis interval;
A beat position detection process for detecting a beat position for the music data in each analysis section or verification section;
Verifying whether or not the beat position detected in each analysis section and the beat position detected in the verification section within each analysis section match,
In the verification interval setting process, based on the beat position detected in each analysis interval, a verification interval is set,
In the analysis section setting process, a beat position estimation program is characterized in that analysis sections are sequentially set over the entire music data based on the verification result.