CN207572057U - A kind of number accuracy in pitch detection module and accuracy in pitch detecting system - Google Patents
A kind of number accuracy in pitch detection module and accuracy in pitch detecting system Download PDFInfo
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- CN207572057U CN207572057U CN201720930345.6U CN201720930345U CN207572057U CN 207572057 U CN207572057 U CN 207572057U CN 201720930345 U CN201720930345 U CN 201720930345U CN 207572057 U CN207572057 U CN 207572057U
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Abstract
The utility model provides a kind of digital accuracy in pitch detection module and accuracy in pitch detecting system, including：Input signal is detected, determines the end-point detection unit of sound head；The output terminal of end-point detection unit is connected to, suitable for determining the main sonification stage acquiring unit of measured signal using sound head as starting point；The output terminal of main sonification stage acquiring unit is connected to, suitable for detecting the first pitch Detection unit of the fundamental frequency for obtaining the first precision to measured signal；The output terminal of the first pitch Detection unit is connected to, the filter unit of the frequency other than frequency separation where being adapted to filter out the fundamental frequency of the first precision；The output terminal of filter unit is connected to, suitable for detecting to obtain the second pitch Detection unit of the fundamental frequency of the second precision to filtered measured signal, the second precision is more than the first precision.The utility model use non real-time detection method, as a result accurately, it is objective；By the way of Digital Signal Processing, fundamental frequency precision can reach 0.01 cent grade；And anti-noise jamming, as a result accuracy is high.
Description
Technical field
The utility model is related to musical instrument detection field, more particularly to a kind of digital accuracy in pitch detection module and accuracy in pitch detection system
System.
Background technology
Current accuracy in pitch detection is mainly used in tune pitching apparatus for music and verifies the two scenes with electronic musical instrument pitch.
It is not stringent to the required precision of result in the scene of tune pitching apparatus for music, allow the error of cent grade.User focuses on making
With impression, it would be desirable to be able to cope with various detection scenes；It needs the real-time response of result, respond at any time.Have at present many ready-made
Solution.
It is very stringent to the required precision of result in the scene of electronic musical instrument pitch verification, it needs to reach cent grade even
Higher precision.Detection mode can standardize, multiple to same signal measurement, as a result should be repeatable；Do not need to be real
When, the plateau after pronouncing with greater need for concern.Existing solution is expensive at present, and still there are problems that.
Such as country light industry musical instrument quality surveillance inspection center (Guangzhou) used Tuning- when detecting pitch
Set CTS-32-C tone correcting devices, price reach ten thousand yuan or more, but in precision, noise immunity, stable reading and objectivity all
There is the problem of larger：
1st, the problem of a maximum of current tone correcting device just in stable reading and objectivity, traditional tone correcting device is substantially
Real time readouts, but the pitch of practical musical instrument is often what is waved.The measurement result subjective factor with someone always is resulted in this way,
A determining objective reading can not be confirmed at all, and after error of the different instruments there are cent grade, no standard can judge to study carefully
Unexpectedly which be only to.
2nd, in precision, by taking Tuning-Set CTS-32-C tone correcting devices as an example, its attainable full accuracy is 0.1 sound
Point.
3rd, in terms of noise immunity, after adding powder noise (- 14db) to a signal, result and standard value that tone correcting device obtains
Deviation is very big, it is impossible to correctly measure result.
Therefore, objectivity, accuracy and the noise immunity of the accuracy in pitch detection in electronic musical instrument pitch verification scene how to be improved
One of those skilled in the art's urgent problem to be solved is become.
Utility model content
In view of the foregoing deficiencies of prior art, the purpose of this utility model is to provide a kind of digital accuracy in pitch detection moulds
Block and accuracy in pitch detecting system, for solve accuracy in pitch detects in electronic musical instrument pitch of the prior art verification scene objectivity,
The problems such as accuracy and noise immunity are low.
In order to achieve the above objects and other related objects, the utility model provides a kind of digital accuracy in pitch detection mould to utility model
Block, the number accuracy in pitch detection module include at least：
The digital signal of input is adapted to detect for, and then determines the end-point detection unit of the sound head of measured signal；
The output terminal of the end-point detection unit is connected to, suitable for obtaining main pronunciation rank by starting point of the sound head
Section, and then determine the main sonification stage acquiring unit of the measured signal；
The output terminal of the main sonification stage acquiring unit is connected to, suitable for carrying out the first fundamental tone to the measured signal
Detection, obtains the first pitch Detection unit of the fundamental frequency of the first precision；
The output terminal of the first pitch Detection unit is connected to, is adapted to filter out frequency where the fundamental frequency of first precision
Frequency other than section, to filter out the filter unit of noise and harmonic wave interference；
The output terminal of the filter unit is connected to, suitable for carrying out the second fundamental tone inspection to the filtered measured signal
It surveys, obtains the second pitch Detection unit of the fundamental frequency of the second precision, the value of the fundamental frequency of second precision is the value of accuracy in pitch, institute
The second precision is stated more than first precision.
Preferably, the filter unit is wave filter.
It is highly preferred that the filter unit is low-pass filter or bandpass filter.
In order to achieve the above objects and other related objects, the utility model also provides a kind of accuracy in pitch detecting system, the sound
Quasi- detecting system includes at least：
Signal collecting device and above-mentioned digital accuracy in pitch detection module；
The signal collecting device receives audio signal to be measured, and data acquisition is carried out to the audio signal to be measured；
The number accuracy in pitch detection module is connected to the output terminal of the signal collecting device, to the signal collecting device
The digital signal of output carries out accuracy in pitch detection, to obtain the accuracy in pitch testing result of the audio signal to be measured.
Preferably, the audio signal to be measured is analog signal or digital signal.
Preferably, the signal collecting device includes memory, computer or sound card.
As described above, the digital accuracy in pitch detection module and accuracy in pitch detecting system of the utility model, have the advantages that：
1st, the method that the utility model uses non real-time detection, can obtain the reading of accurate stable, solve existing accuracy in pitch
Reading changes always in instrument, causes result inaccuracy, one sided problem.
2nd, for the utility model by the way of Digital Signal Processing, the fundamental frequency precision finally obtained is high, can reach 0.01 sound
The precision of classification, significantly larger than existing solution.
3rd, the utility model excludes noise jamming in detection process, improves the accuracy of result.
Description of the drawings
Fig. 1 is shown as the principle schematic of the digital accuracy in pitch detection technique of the utility model.
Fig. 2 is shown as the structure diagram of the digital accuracy in pitch detection module of the utility model.
Fig. 3 is shown as the structure diagram of the accuracy in pitch detecting system of the utility model.
Component label instructions
S1~S5 steps
S11~S13, S31~S32, S51~S52 steps
1 digital accuracy in pitch detection module
11 end-point detection units
12 main sonification stage acquiring units
13 first pitch Detection units
14 filter units
15 second pitch Detection units
2 musical instruments to be measured
3 sound cards
4 accuracy in pitch detecting systems
Specific embodiment
Illustrate the embodiment of the utility model below by way of specific specific example, those skilled in the art can be by this theory
Content disclosed by bright book understands other advantages and effect of the utility model easily.The utility model can also be by addition
Different specific embodiments are embodied or practiced, and the various details in this specification can also be based on different viewpoints with answering
With carrying out various modifications or alterations under the spirit without departing from the utility model.
Please refer to Fig.1~Fig. 3.It should be noted that the diagram provided in the present embodiment only illustrates this in a schematic way
The basic conception of utility model, when only display is with related component in the utility model rather than according to actual implementation in schema then
Component count, shape and size are drawn, and kenel, quantity and the ratio of each component can be a kind of random change during actual implementation
Become, and its assembly layout kenel may also be increasingly complex.
Embodiment one
As shown in Figure 1, the utility model provides a kind of digital accuracy in pitch detection technique, the number accuracy in pitch detection technique is at least
Including：
Step S1：End-point detection is carried out to the digital signal of input, to determine the sound head of measured signal.
Specifically, the signal of input is digital signal, and the digital signal of same sound input is identical, to ensure to input
Digital signal in do not bring artificial factor (dynamics, compressing time etc.) into, to improve the objectivity of testing result.Based on described
Sound head distinguishes the music signal period in the digital signal of input and unmusical signal time slot, with accurate definition music signal
Starting point.In the present embodiment, the digital signal of input is given tacit consent to for monophonic, sample rate fS=44100Hz；To bilateral
Road signal is detected, then channel is needed point or so to be detected respectively, is not repeated one by one herein.
Specifically, the end-point detection specifically includes following steps：
Step S11：The energy of each sampled point of the digital signal is calculated successively.
More specifically, in the present embodiment, it is possible to measure the absolute value for signal.
Step S12：By the energy of each sampled point of the digital signal and the average energy of its setting quantity sampled point previous
Amount is compared.
More specifically, when the setting quantity is more, the ability of anti-noise jamming is weaker；When the setting number
When measuring very little, endpoint may be can't detect, and then can not determine the sound head of the measured signal.Therefore, in the present embodiment
In, the quantity that sets also can be zoomed in or out suitably to 128~4096 (including 128 and 4096) as 1024.In practical application
In, the value of the setting quantity can be determined according to equipment and environmental factor, accurate sound head position can be obtained by being subject to, not with this
Embodiment is limited.
Step S13：If the ratio of the two is more than setting ratio, the energy production mutation of current sampling point is judged, it ought
Preceding sampled point is defined as the sound head of the measured signal.
More specifically, when the setting ratio is bigger, the response that end-point detection generates mutation is slower, works as institute
State setting ratio it is smaller when, the ability of anti-noise jamming is weaker.In the present embodiment, the ratio of the two is set as：When
The average energy of the energy of preceding sampled point/preceding setting quantity sampled point, in the present embodiment, the setting ratio are set as 8,
Also it can suitably zoom in or out to 4~16 (including 4 and 16).The ratio of the two can also be set as：Preceding setting quantity sampling
Ranging from upper a kind of inverse of situation of the energy of average energy/current sampling point of point, then the setting ratio, differs herein
One repeats.In practical applications, can be weighed between response speed and anti-noise jamming ability, to determine the setting ratio
The numerical value of value, is not limited to this embodiment.
Step S2：Main sonification stage is obtained, and then determine the measured signal by starting point of the sound head.
Specifically, in the present embodiment, give tacit consent in the case that the sample rate of the digital signal of input is 44100, take described
Signal of 65536 sampled points as main sonification stage after sound head starting point, using the signal of main sonification stage as institute
State measured signal, in the present embodiment, the main sonification stage when a length of 1.5 seconds, when sample rate changes,
The sampled point number taken is also required to be changed accordingly, can suitably zoom in or out to 1~2s.In practical applications, may be used
Different main sonification stage durations is set according to the pronunciation length of input signal, is not limited to this embodiment.
Step S3：First pitch Detection is carried out to the measured signal, obtains the fundamental frequency of the first precision.
Specifically, first pitch Detection specifically includes following steps：
Step S31：The spectrogram of the measured signal is obtained, the spectrogram of the measured signal is divided in the X-axis direction
Integral multiple is not compressed, to obtain multiple compression spectrograms.
More specifically, in the present embodiment, Fast Fourier Transform (FFT) (Fast Fourier are carried out to the measured signal
Transformation, FFT), the spectrogram of the measured signal is obtained, the X-axis of spectrogram is frequency, and Y-axis is power.By institute
The spectrogram for stating measured signal compresses 2,3,4,5 times (i.e. to its X-axis divided by 2,3,4,5) respectively in the X-axis direction, to obtain 4
A compression spectrogram.By to spectrogram compression in the X-axis direction can by second harmonic, triple-frequency harmonics, four-time harmonic, five times
Harmonic compression and the position for moving first harmonic, in practical applications, the multiple of compression can be configured according to actual needs,
It is not limited to this embodiment.
Step S32：Former spectrogram and each compression spectrogram are superimposed by reference point of origin, i.e., each harmonic wave exists
The position overlapping of first harmonic.
Specifically, former spectrogram with each compression spectrogram is superimposed, the coordinate points on former spectrogram is made to be sat with its integral multiple
Coordinate points superposition in punctuate near zone corresponding to amplitude maximum, the X-axis coordinate after superposition corresponding to amplitude maximum are determined
Justice is the fundamental frequency of first precision.First precision is low precision.In the present embodiment, the near zone is
[0.9f1,1.1f1], wherein, f1 is each harmonic coordinate points on each coordinate compressed in spectrogram X-axis, i.e., former spectrogram
Integral multiple.In practical applications, can the near zone be set according to the change frequency of spectrogram, be not limited to this embodiment.
Distinguishingly, when the harmonic frequency of the measured signal is fixed as the integral multiple of fundamental frequency, amplitude maximum institute is right near zone
The coordinate points answered are exactly the integral multiple of the coordinate points on former spectrogram.
Step S4：Frequency other than frequency separation where filtering out the fundamental frequency of first precision, to eliminate noise and harmonic wave
Interference.
Specifically, in the present embodiment, three rank band logical Barts is used to irrigate hereby (Butterworth) wave filter described to filter out
All frequencies other than frequency separation where the fundamental frequency of first precision, to exclude harmonic wave and interference of the noise to fundamental frequency.Described
Frequency separation where the fundamental frequency of one precision is set as [0.8f2,1.25f2], wherein, f2 is the fundamental frequency place of first precision
Frequency, i.e., the corresponding X-axis coordinate of coincidence point or maximum value mentioned above.In practical applications, it can be wanted according to precision, accuracy
Frequency separation where seeking the fundamental frequency for setting first precision, is not limited to this embodiment.
Step S5：Second pitch Detection is carried out to the filtered measured signal, obtains the fundamental frequency of the second precision, it is described
The value of the fundamental frequency of second precision is the value of accuracy in pitch.
Specifically, second pitch Detection specifically includes following steps：
Step S51：The spectrogram of the filtered measured signal is obtained, to the frequency spectrum of the filtered measured signal
The absolute value of each power carries out resampling in figure.
More specifically, in the present embodiment, Fast Fourier Transform (FFT) is carried out to the filtered measured signal, obtains filter
The spectrogram of the measured signal after wave, the X-axis of spectrogram is frequency, and Y-axis is power.According to Nyquist (Nyquist)
Sampling theorem has formula (1)：
In the present embodiment, sampling interval Ts is set as 1, the value range of Integer n be set as -20~20 including (- 20 and
20)。
Then there is formula (2)：
Wherein, x (fn) for the filtered measured signal spectrogram in power absolute value, xa(f) it is x (fn) weight
After sampling in spectrogram power absolute value, fnFor integer, f attaches most importance to sampled point.
Using formula (2) to the absolute value x (f of power in the filtered measured signal spectrogramn) carry out 128 times
Resampling improves result precision with this.
Step S52：The corresponding X-axis coordinate of the point of power maximum absolute value is the base of second precision after resampling
Frequently.Second precision is high-precision, and second precision is much larger than first precision.
Embodiment two
As shown in Fig. 2, the utility model provides a kind of digital accuracy in pitch detection module 1, it is used to implement described in embodiment one
Digital accuracy in pitch detection technique.
As shown in Fig. 2, the number accuracy in pitch detection module 1 includes end-point detection unit 11, main sonification stage obtains list
First 12, first pitch Detection unit 13,14 and second pitch Detection unit 15 of filter unit.
Specifically, the end-point detection unit 11 is for detecting the digital signal of input, and then determines the sound of measured signal
Head.
Specifically, the main sonification stage acquiring unit 12 is connected to the output terminal of the end-point detection unit 11, with
The sound head obtains main sonification stage for starting point, and then determines the measured signal.
Specifically, the first pitch Detection unit 13 is connected to the output of the main sonification stage acquiring unit 12
End for carrying out the first pitch Detection to the measured signal, obtains the fundamental frequency of the first precision.
Specifically, the filter unit 14 is connected to the output terminal of the first pitch Detection unit 13, for filtering out
Frequency other than frequency separation where stating the fundamental frequency of the first precision, to filter out noise and harmonic wave interference.In the present embodiment, it is described
Filter unit 14 irrigates hereby (Butterworth) wave filter for three rank band logical Barts, in practical applications, low-pass filter can be used
Or other bandpass filters, it is not limited to this embodiment.
Specifically, the second pitch Detection unit 15 is connected to the output terminal of the filter unit 14, for filtering
The measured signal afterwards carries out the second pitch Detection, obtains the fundamental frequency of the second precision, the value of the fundamental frequency of second precision is
For the value of accuracy in pitch, second precision is more than first precision.
Content of the concrete function of each unit recorded in referring to embodiment one, does not repeat one by one in the present embodiment.
Embodiment three
As shown in figure 3, the utility model also provides a kind of accuracy in pitch detecting system 4, including audio signal to be measured, signal acquisition
Equipment, sound card 3 and the digital accuracy in pitch detection module 1.
Specifically, in the present embodiment, the audio signal to be measured is provided by musical instrument 2 to be measured, the musical instrument 2 to be measured exports
The analog signal or digital signal of musical sound.
Specifically, the signal collecting device receives the audio signal to be measured, for the audio signal to be measured into
Row data acquire.The signal collecting device includes but not limited to memory, computer and sound card.In the present embodiment, using sound
Card 3 realizes data acquisition, and the sound card 3 is connected to the output terminal of the musical instrument to be measured 2, for the analog signal to be converted into
Digital signal.
Specifically, the digital accuracy in pitch detection module 1 is connected to the output terminal of the sound card 3, for believing the number
Number carry out accuracy in pitch detection, to obtain the accuracy in pitch testing result of the musical instrument to be measured 2.The number accuracy in pitch detection module 1 it is specific
Content of the structure and working principle recorded in referring to embodiment one and embodiment two, does not repeat one by one in the present embodiment.
The method that the utility model uses non real-time detection, can obtain the reading of accurate stable, solve existing tone correcting device
Middle reading changes always, causes result inaccuracy, one sided problem；The utility model by the way of Digital Signal Processing,
The fundamental frequency precision finally obtained is high, can reach the precision of 0.01 cent grade, significantly larger than existing solution；The utility model
In calculating process, noise jamming is excluded, improves the accuracy of result.
In conclusion the utility model provides a kind of digital accuracy in pitch detection module and accuracy in pitch detecting system, including：Suitable for inspection
The digital signal of input is surveyed, and then determines the end-point detection unit of the sound head of measured signal；It is connected to the end-point detection unit
Output terminal, suitable for obtaining main sonification stage by starting point of the sound head, and then determine the main hair of the measured signal
Scale section acquiring unit；The output terminal of the main sonification stage acquiring unit is connected to, suitable for being carried out to the measured signal
First pitch Detection obtains the first pitch Detection unit of the fundamental frequency of the first precision；It is connected to the first pitch Detection unit
Output terminal, the frequency other than frequency separation where being adapted to filter out the fundamental frequency of first precision done with filtering out noise and harmonic wave
The filter unit disturbed；The output terminal of the filter unit is connected to, suitable for carrying out the second base to the filtered measured signal
Sound detects, and obtains the second pitch Detection unit of the fundamental frequency of the second precision, the value of the fundamental frequency of second precision is accuracy in pitch
Value, second precision are more than first precision.The utility model use non real-time detection method, as a result accurately, it is objective；
And the utility model, by the way of Digital Signal Processing, the fundamental frequency precision obtained is high, can reach the precision of 0.01 cent grade, far
Far above existing solution；In addition the utility model excludes noise jamming, can effectively improve result in detection is calculated
Accuracy.So the utility model effectively overcomes various shortcoming of the prior art and has high industrial utilization.
The above embodiments are only illustrative of the principle and efficacy of the utility model, new not for this practicality is limited
Type.Any person skilled in the art can all carry out above-described embodiment under the spirit and scope without prejudice to the utility model
Modifications and changes.Therefore, such as those of ordinary skill in the art without departing from the revealed essence of the utility model
All equivalent modifications completed under refreshing and technological thought or change, should be covered by the claim of the utility model.
Claims (6)
1. a kind of number accuracy in pitch detection module, which is characterized in that the number accuracy in pitch detection module includes at least：
The digital signal of input is adapted to detect for, and then determines the end-point detection unit of the sound head of measured signal；
The output terminal of the end-point detection unit is connected to, suitable for obtaining main sonification stage by starting point of the sound head, into
And determine the main sonification stage acquiring unit of the measured signal；
The output terminal of the main sonification stage acquiring unit is connected to, suitable for carrying out the first fundamental tone inspection to the measured signal
It surveys, obtains the first pitch Detection unit of the fundamental frequency of the first precision；
The output terminal of the first pitch Detection unit is connected to, is adapted to filter out frequency separation where the fundamental frequency of first precision
Frequency in addition, to filter out the filter unit of noise and harmonic wave interference；
The output terminal of the filter unit is connected to, suitable for carrying out the second pitch Detection to the filtered measured signal, is obtained
To the second pitch Detection unit of the fundamental frequency of the second precision, the value of the fundamental frequency of second precision is the value of accuracy in pitch, and described
Two precision are more than first precision.
2. number accuracy in pitch detection module according to claim 1, it is characterised in that：The filter unit is wave filter.
3. number accuracy in pitch detection module according to claim 1 or 2, it is characterised in that：The filter unit is low pass filtered
Wave device or bandpass filter.
4. a kind of accuracy in pitch detecting system, which is characterized in that the accuracy in pitch detecting system includes at least：
Signal collecting device and the digital accuracy in pitch detection module as described in claims 1 to 3 any one；
The signal collecting device receives audio signal to be measured, and data acquisition is carried out to the audio signal to be measured；
The number accuracy in pitch detection module is connected to the output terminal of the signal collecting device, and the signal collecting device is exported
Digital signal carry out accuracy in pitch detection, to obtain the accuracy in pitch testing result of the audio signal to be measured.
5. accuracy in pitch detecting system according to claim 4, it is characterised in that：The audio signal to be measured for analog signal or
Digital signal.
6. accuracy in pitch detecting system according to claim 4, it is characterised in that：The signal collecting device include memory,
Computer or sound card.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112489682A (en) * | 2020-11-25 | 2021-03-12 | 平安科技（深圳）有限公司 | Audio processing method and device, electronic equipment and storage medium |
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2017
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112489682A (en) * | 2020-11-25 | 2021-03-12 | 平安科技（深圳）有限公司 | Audio processing method and device, electronic equipment and storage medium |
| WO2021213135A1 (en) * | 2020-11-25 | 2021-10-28 | 平安科技（深圳）有限公司 | Audio processing method and apparatus, electronic device and storage medium |
| CN112489682B (en) * | 2020-11-25 | 2023-05-23 | 平安科技（深圳）有限公司 | Audio processing method, device, electronic equipment and storage medium |
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