CN101770778B - Pre-emphasis filter, perception weighted filtering method and system - Google Patents
Pre-emphasis filter, perception weighted filtering method and system Download PDFInfo
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- CN101770778B CN101770778B CN2008102205797A CN200810220579A CN101770778B CN 101770778 B CN101770778 B CN 101770778B CN 2008102205797 A CN2008102205797 A CN 2008102205797A CN 200810220579 A CN200810220579 A CN 200810220579A CN 101770778 B CN101770778 B CN 101770778B
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Abstract
The embodiment of the invention discloses a pre-emphasis filter, a perception weighted filtering method and a system; the pre-emphasis filter comprises a parameter determining module, a configuration module and a filtering module; the perception weighted filtering method comprises the following steps: the parameters of the pre-emphasis filter are determined according to low-frequency energy and high-frequency energy of an input signal; the pre-emphasis filter is arranged according to the parameters, the input signal is processed to obtain a first signal by the pre-emphasis filter; linear prediction LP analysis is carried out to the first signal, the coefficient of the perception weighted filter is determined; the perception weighted filter is arranged according to parameters and coefficients, and filtering is carried out to the first signal through the perception weighted filter; the perception weighted system mainly comprises the pre-emphasis filter, an LP filter, the configuration module and the perception weighted filter; by adopting the embodiment of the invention, the subjective hearing effect of voice coding is improved, and the invention is widely suitable for hybrid coding mode and can strictly control the complexity of the algorithm.
Description
Technical field
The present invention relates to multimedia technology field, relate in particular to a kind of preemphasis filter, perception weighted filtering method and system.
Background technology
People's ear receives the influence of simultaneous another one pure tone to the auditory perception property of a pure tone, but people's the sense of hearing previous pure tone of perception clearly still, and this phenomenon is called the masking effect of people's ear.
When carrying out voice coding; The masking effect that can utilize people's ear is that the noise at resonance peak place is not easy to be perceiveed for the noise of low-frequency range with respect to energy, through in the bigger distortion of resonance peak region allocation, reduces the bigger noise of subjective feeling in the resonance peak valley; Thereby weaken the importance in formant frequency zone; Improve code efficiency, and obtain preferable subjective auditory effect, this speech coding technology is called the perception weighted filtering technology.
The inventor finds in realizing process of the present invention, the voice coding of current application comparative maturity mainly at 200Hz on the telephone bandwidth of 3400Hz.Be used in this arrowband scope and mainly adopt with Algebraic Code Excited Linear Prediction (Algebraic Code Excited Linear Prediction; ACELP) be the technical scheme of core; In order to realize noise in the weighting territory by the resonance peak structure partition noise, the narrowband speech coding has used the perceptual weighting filter form of following form:
This wave filter resonance peak structure of analog voice frequency spectrum preferably in narrowband speech coding, but in broadband signal, owing to have bigger dynamic range between low frequency and the high frequency; The signal spectrum inclined degree is more obvious; Therefore, in the AMR-WB speech coding technology of expansion, the preemphasis filter through adopting parameter preset carries out Filtering Processing to the high and low frequency of primary speech signal; Reduce dynamic range of signals, but cause the subjective auditory effect of voice coding poor.
Summary of the invention
The embodiment of the invention provides a kind of preemphasis filter, perception weighted filtering method and system, and the characteristics of foundation coding frequency spectrum itself are adjusted parameter, the coefficient of preemphasis filter, have improved the auditory effect of voice coding.
In the one side of the embodiment of the invention, provide a kind of preemphasis filtering implement body to comprise:
The parameter determination module is used for the parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input signal;
Configuration module, the parameter that is used to adopt said parameter determination module to confirm is configured filtration module;
Said filtration module is used for said input signal is carried out exporting after the Filtering Processing.
In the embodiment of the invention on the other hand, provide a kind of perception weighted filtering method specifically to comprise:
The parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input signal;
According to said parameter preemphasis filter is set, and through said preemphasis filter said input signal is carried out Filtering Processing and obtain first signal;
Said first signal is linear prediction LP analyzes, confirm the coefficient of perceptual weighting filter;
According to said parameter, said coefficient said perceptual weighting filter is set, and said first signal is carried out Filtering Processing through said perceptual weighting filter.
Aspect the embodiment of the invention another, provide a kind of perception weighted filtering system specifically to comprise:
Preemphasis filter is used for confirming parameter according to the low frequency energy and the high-frequency energy of input signal, and input signal is carried out exporting first signal after the Filtering Processing;
The LP wave filter is used for that first signal is carried out LP and analyzes, and obtains the coefficient of perceptual weighting filter;
Dispensing unit is used for according to parameter and said coefficient that said preemphasis filter is confirmed perceptual weighting filter being set;
Said perceptual weighting filter is used for said first signal is handled back output.
Embodiment of the invention technical matters to be solved is; A kind of preemphasis filter, perception weighted filtering method and system are provided; Through adjust parameter, the coefficient of wave filter according to the characteristics (low frequency energy and high-frequency energy) of coding frequency spectrum itself; Simulate the resonance peak structure and spectrum incline structure of signal spectrum, realize that in the weighting territory noise distributes according to the resonance peak structure of signal, has improved the subjective auditory effect of voice coding; And the embodiment of the invention can be applicable to ACELP and TCX to be the hybrid coding pattern of core; Be applied to voice or audio codec that other adopts the ACELP of preemphasis filter, complexity that can strict control algolithm reduces the bit rate of transmission.
Description of drawings
Fig. 1 is the overall flow figure of a kind of perception weighted filtering method of providing of the embodiment of the invention;
Fig. 2 is the process flow diagram of a kind of perception weighted filtering method of providing of the embodiment of the invention;
Fig. 3 is the process flow diagram of S1 in a kind of perception weighted filtering method of providing of the embodiment of the invention;
Fig. 4 is that parameter is switched synoptic diagram among the said S1 of Fig. 3;
Fig. 5 is the structural representation of a kind of preemphasis filter of providing of the embodiment of the invention;
Fig. 6 is first structural representation of the described parameter determination module of Fig. 5;
Fig. 7 is second structural representation of the described parameter determination module of Fig. 6;
Fig. 8 is the described structural representation that seamlessly transits submodule of Fig. 7;
Fig. 9 is the structural representation of the described selection transition mode of Fig. 8 unit;
Figure 10 is the structural drawing of a kind of perception weighted filtering system that provides of the embodiment of the invention.
Embodiment
The embodiment of the invention provides a kind of preemphasis filter, perception weighted filtering method and system; Improved the subjective auditory effect of voice coding; And the embodiment of the invention can be applicable to that (Transform coded excitation is the hybrid coding pattern of core TCX), is applied to voice or audio codec with changing coding with ACELP; Complexity that can strict control algolithm reduces the bit rate of transmission.
For the purpose, technical scheme and the advantage that make the embodiment of the invention is clearer, will combine accompanying drawing that the embodiment of the invention is done to describe in detail further below.
With reference to figure 1, be the process flow diagram of a kind of perception weighted filtering method of providing of the embodiment of the invention, specifically comprise:
S1: the parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input signal;
S2: according to said parameter preemphasis filter is set, and through said preemphasis filter said input signal is carried out Filtering Processing and obtain first signal;
S3: said first signal is linear prediction LP analyzes, confirm the coefficient of perceptual weighting filter;
S4: according to said parameter, said coefficient said perceptual weighting filter is set, and said first signal is carried out Filtering Processing through said perceptual weighting filter.
Wherein, In S1; According to the parameter that the low frequency energy and the high-frequency energy of input signal are confirmed preemphasis filter, specifically can confirm the parameter of preemphasis filter according to the spectrum inclined degree of input signal, said spectrum inclined degree has reflected the height of low frequency and high-frequency energy.Therefore, as shown in Figure 3, the parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input signal specifically comprises:
S11: judge according to the spectrum inclined degree whether said input signal medium and low frequency energy is higher than high-frequency energy;
S12: when judged result when being, the span of said parameter μ is less than 0, for example: 0＞μ＞-1;
S13: when judged result for not the time, said parameter range is greater than 0, for example: 1＞μ＞0.
Need to prove; In specific embodiment of the present invention; Said spectrum inclined degree according to input signal confirms that the parameter of preemphasis filter is specially: handle through input signal is divided into Frame; The frequency spectrum of the signal of every frame can present different spectrum inclined degrees; Said different spectrum inclined degree reflected low frequency energy apparently higher than high-frequency energy, low frequency energy be higher than high-frequency energy, low frequency energy and high-frequency energy quite, low frequency energy is lower than high-frequency energy, low frequency energy is starkly lower than high-frequency energy; When the symbol of confirming parameter μ and numerical value, the difference of symbol is corresponding to two kinds of corresponding wave filters of parameter described in S12 and the S13, and the order of magnitude of parameter μ has reflected the degree that spectrum tilts.
Wherein, The spectrum inclined degree of each frame signal can be characterized by information such as spectrum flatness, spectral decay speed; When calculating the characterization value of spectrum flatness; Can take dual mode: a kind of is directly to calculate with input signal, and another kind is to use the A as a result (z) to the linear prediction filtering of each frame signal to calculate.
Calculating the characterization value of composing flatness with the A (z) through each frame signal below is example, is elaborated:
To the coefficient of A (z) 1, a
1... a
16(Fast FourierTransform FFT) obtains the sequence of complex numbers { C of frequency domain to do the Fast Fourier Transform (FFT) on 32 rank
i(i=1...32), use
Represent low frequency energy the decibel estimated value,
Represent the decibel estimated value of high-frequency energy, the mean difference that calculates the two characterizes the spectrum flatness, is designated as Δ:
Perhaps the signal of input is done the sequence of complex numbers that the FFT conversion obtains frequency domain; Do the calculating of formula (1) too; It should be appreciated by those skilled in the art that because input signal sequence is longer, the FFT variation factor is a lot; So the parameter area of summation changes to some extent in the formula (1), but does not influence realization of the present invention.
The spectrum inclined degree that mean difference through the low frequency that obtains based on aforementioned calculation and high-frequency energy characterizes is confirmed the parameter of preemphasis filter, is specially the distribution range according to difference DELTA, the value of the parameter μ that mapping look-up of table 1 obtains.
Table 1
| Δ | u |
| [∞, thresholding 0] | +0.68 |
| [ |
+0.45 |
| [ |
+0.3 |
| [thresholding 2, thresholding 3] | +0.1 |
| [thresholding 3, thresholding 4] | -0.1 |
| [thresholding 4, thresholding 5] | -0.3 |
| [thresholding 5, thresholding 6] | -0.45 |
| [thresholding 6 ,+∞] | -0.68 |
Wherein, the threshold value value, those skilled in the art can be provided with according to concrete application, for example:
Thresholding 0:-25
Thresholding 1:-20
Thresholding 2:-10
Thresholding 3:0
Thresholding 4:10
Thresholding 5:20
To the original signal of input, different at its spectrum inclined degree of different frames, the parameter μ that confirms according to the spectrum inclined degree is different; Therefore, to whole input term signal, when said parameter changes; Said step S1 also comprises: said parameter seamlessly transitted, and as shown in Figure 4, show the synoptic diagram that seamlessly transits of parameter μ; When the parameter sign change appearred in said input signal, through the transition of n frame, n was a positive integer in the middle of adopting.Parameter μ is that unit carries out the transition change switching with a frame of encoding process.In Fig. 4, frame number promptly is the situation when n gets 0 from N-12 to N-5.
Under the situation that the frame parameter symbol is identical when the front and back of said input signal, value changes; Employing waits the transition of slope multiframe, and is as shown in Figure 4, waits slope specifically to can be the modes such as oblique line, curve of gradual change; Wherein, Frame number promptly is the oblique line of gradual change from N+3 to N+7, and frame number is the curve of gradual change from N+10 to N+16.
Also can adopt both combinations, promptly when parameter sign change, value change, the transition of slope multiframe such as also can adopt, in Fig. 4, frame number from N to N+7 or frame number from N+16 to N+20.
The perception weighted filtering method that the embodiment of the invention provides; Through adjust parameter, the coefficient of wave filter according to the characteristics of coding frequency spectrum itself; Simulate the resonance peak structure and spectrum incline structure of signal spectrum; Realize that in the weighting territory noise distributes according to the resonance peak structure of signal, has improved the subjective auditory effect of voice coding.
Through the description of above embodiment, those skilled in the art can be well understood to the present invention and can realize by the mode that software adds essential hardware platform, can certainly all implement through hardware.Based on such understanding; All or part of can the coming out that technical scheme of the present invention contributes to background technology with the embodied of software product; This computer software product can be stored in the storage medium, like ROM/RAM, magnetic disc, CD etc., comprises that some instructions are with so that a computer equipment (can be a personal computer; Server, the perhaps network equipment etc.) carry out the described method of some part of each embodiment of the present invention or embodiment.
Accordingly, the embodiment of the invention also provides a kind of perception weighted filtering system, with reference to Figure 10, specifically comprises:
Preemphasis filter 101 is used for confirming parameter according to the low frequency energy and the high-frequency energy of input signal, and input signal is carried out exporting first signal after the Filtering Processing;
LP wave filter 102 is used for that first signal is carried out LP and analyzes, and obtains the coefficient of perceptual weighting filter 94;
Dispensing unit 103 is used for according to parameter, said coefficient that said preemphasis filter 101 is confirmed perceptual weighting filter 104 being set, and the parameter of said preemphasis filter 101 is to confirm according to the spectrum inclined degree of said input signal;
Said perceptual weighting filter 104 is used for said first signal is handled back output.
The concrete structure synoptic diagram of wherein said preemphasis filter 101 is as shown in Figure 5, specifically comprises:
Said filtration module 53 is used for said input signal is carried out exporting after the Filtering Processing.
With reference to figure 6, be first structural representation of parameter determination module 51 in the said preemphasis filter 101, wherein, said parameter determination module 51 specifically comprises:
Fig. 6 is second structural representation of parameter determination module 51 in the said preemphasis filter 101, and the parameter determination module also comprises except the structure with Fig. 6:
Seamlessly transit submodule 513, be used for when said parameter changes, said parameter being seamlessly transitted.
With reference to figure 8, the said submodule 513 that seamlessly transits specifically comprises:
Preference pattern unit 5132 is used for switching the dimensional discrepancy degree according to said parameter and selects the transition mode that is provided with in advance.
Wherein the concrete structure of preference pattern unit is as shown in Figure 9, specifically comprises:
On slope transition subelement 51321, be used to wait the transition of slope multiframe;
Described perception weighted filtering system can be applicable to ACELP with change the hybrid coding pattern that is encoded to core, be applied to voice or audio codec.
Embodiment of the invention technical matters to be solved is; A kind of preemphasis filter, perception weighted filtering method and system are provided,, have simulated the resonance peak structure and spectrum incline structure of signal spectrum through adjust parameter, the coefficient of wave filter according to the characteristics of coding frequency spectrum itself; Realize that in the weighting territory noise distributes according to the resonance peak structure of signal; Improved the subjective auditory effect of voice coding, and the embodiment of the invention can be applicable to ACELP with change the hybrid coding pattern be encoded to core, be applied to voice or audio codec; Complexity that can strict control algolithm reduces the bit rate of transmission.
Above disclosedly be merely a kind of preferred embodiment of the present invention, can not limit the present invention's interest field certainly with this, the equivalent variations of therefore doing according to claim of the present invention still belongs to the scope that the present invention is contained.
Claims (14)
1. a perception weighted filtering method is characterized in that, specifically comprises:
The parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input speech signal;
According to said parameter preemphasis filter is set, and through said preemphasis filter said input speech signal is carried out Filtering Processing and obtain first signal;
Said first signal is linear prediction LP analyzes, confirm the coefficient of perceptual weighting filter;
According to said parameter, said coefficient said perceptual weighting filter is set, and said first signal is carried out Filtering Processing through said perceptual weighting filter;
Wherein, the said parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input speech signal comprises:
Obtain the high-frequency energy and the low frequency energy of each frame signal in the input speech signal;
Utilize spectrum more said low frequency energy of inclined degree and high-frequency energy, confirm the parameter of preemphasis filter according to the result of said comparison;
Wherein, said utilization spectrum more said low frequency energy of inclined degree and high-frequency energy, confirm that according to the result of said comparison the parameter of preemphasis filter comprises:
Judge according to the spectrum inclined degree whether said input speech signal medium and low frequency energy is higher than high-frequency energy;
When judged result when being, said parameter range is less than 0;
When judged result for not the time, said parameter range is greater than 0.
2. perception weighted filtering method as claimed in claim 1 is characterized in that, said utilization spectrum more said low frequency energy of inclined degree and high-frequency energy confirm that according to the result of said comparison the parameter of preemphasis filter specifically also comprises:
When said parameter changes, said parameter is seamlessly transitted.
3. perception weighted filtering method as claimed in claim 2 is characterized in that, and is said when said parameter changes, and said parameter seamlessly transitted specifically comprise:
With said parameter by frame, seamlessly transit or select the transition mode that is provided with in advance gradually according to the switching dimensional discrepancy degree of said parameter.
4. perception weighted filtering method as claimed in claim 3 is characterized in that, the said transition mode of selecting to be provided with in advance according to the switching dimensional discrepancy degree of said parameter specifically comprises:
Under the situation that the frame parameter symbol is identical when the front and back of said input speech signal, value changes, employing waits the transition of slope multiframe;
When the parameter sign change appearred in said input speech signal, through the transition of n frame, n was a positive integer in the middle of adopting.
5. a preemphasis filter is characterized in that, specifically comprises:
The parameter determination module is used for the parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input speech signal;
Configuration module, the parameter that is used to adopt said parameter determination module to confirm is configured filtration module;
Said filtration module is used for said input speech signal is carried out exporting after the Filtering Processing;
Wherein, said parameter determination module specifically comprises:
Judge submodule, be used for judging according to the spectrum inclined degree whether said input speech signal medium and low frequency energy is higher than high-frequency energy;
Processing sub, be used for when said judgement submodule output result when being, said parameter range be less than 0, when the output result of said judgement submodule is when denying, said parameter range is greater than 0.
6. preemphasis filter as claimed in claim 5 is characterized in that, said parameter determination module specifically also comprises:
Seamlessly transit submodule, be used for when said parameter changes, said parameter being seamlessly transitted.
7. preemphasis filter as claimed in claim 6 is characterized in that, the said submodule that seamlessly transits specifically comprises:
Excessive one by one unit is used for said parameter is pursued frame, seamlessly transitted gradually.
8. like claim 6 or 7 described preemphasis filters, it is characterized in that the said submodule that seamlessly transits comprises:
The preference pattern unit is used for selecting the transition mode that is provided with in advance according to the switching dimensional discrepancy degree of said parameter.
9. preemphasis filter as claimed in claim 8 is characterized in that, said preference pattern unit specifically comprises:
On slope transition subelement, be used to wait the transition of slope multiframe;
Switch subelement fast, be used to switch fast, promptly middle transient mode through n frame, n is a positive integer;
The chooser unit when being used for, value identical when the front and back of said input speech signal frame parameter symbol and changing, selects said subelement such as transition such as slope such as grade to handle; When the parameter sign change appears in said input speech signal, select to switch subelement fast and handle.
10. preemphasis filter as claimed in claim 5 is characterized in that, the expression formula of said preemphasis filter is:
H(z)＝1+μz
-1，
Wherein μ is the parameter of preemphasis filter, and z is a complex variable.
11. a perceptual weighting system is characterized in that, specifically comprises:
Preemphasis filter is used for confirming parameter according to the low frequency energy and the high-frequency energy of input speech signal, and input speech signal is carried out exporting first signal after the Filtering Processing;
The LP wave filter is used for that first signal is carried out linear prediction LP and analyzes, and obtains the coefficient of perceptual weighting filter;
Dispensing unit is used for according to parameter and said coefficient that said preemphasis filter is confirmed perceptual weighting filter being set;
Said perceptual weighting filter is used for said first signal is handled back output;
Wherein, said preemphasis filtering implement body comprises:
The parameter determination module is used for the parameter of confirming preemphasis filter according to the low frequency energy and the high-frequency energy of input speech signal;
Configuration module, the parameter that is used to adopt said parameter determination module to confirm is configured filtration module;
Said filtration module is used for said input speech signal is carried out exporting after the Filtering Processing;
Wherein, said parameter determination module specifically comprises:
Judge submodule, be used for judging according to the spectrum inclined degree whether said input speech signal medium and low frequency energy is higher than high-frequency energy;
Processing sub, be used for when said judgement submodule output result when being, said parameter range be less than 0, when the output result of said judgement submodule is when denying, said parameter range is greater than 0.
12. perceptual weighting as claimed in claim 11 system is characterized in that said parameter determination module specifically also comprises:
Seamlessly transit submodule, be used for when said parameter changes, said parameter being seamlessly transitted.
13. perceptual weighting as claimed in claim 11 system is characterized in that the expression formula of said preemphasis filter is:
H(z)＝1+μz
-1，
Wherein μ is the parameter of preemphasis filter, and z is a complex variable.
14. perceptual weighting as claimed in claim 11 system, it is characterized in that: said perceptual weighting filter expression formula is:
Wherein μ is the parameter of preemphasis filter, and z is a complex variable, and λ is a weighting coefficient, and 1=＞λ＞0, and A (z) is the LP wave filter.
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| US9510125B2 (en) * | 2014-06-20 | 2016-11-29 | Microsoft Technology Licensing, Llc | Parametric wave field coding for real-time sound propagation for dynamic sources |
| US10602298B2 (en) | 2018-05-15 | 2020-03-24 | Microsoft Technology Licensing, Llc | Directional propagation |
| US10932081B1 (en) | 2019-08-22 | 2021-02-23 | Microsoft Technology Licensing, Llc | Bidirectional propagation of sound |
| CN113643689B (en) * | 2021-07-02 | 2023-08-18 | 北京华捷艾米科技有限公司 | Data filtering method and related equipment |
| CN113691393A (en) * | 2021-07-14 | 2021-11-23 | 深圳市联洲国际技术有限公司 | Communication quality optimization method, device, equipment and storage medium based on pre-emphasis |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6006174A (en) * | 1990-10-03 | 1999-12-21 | Interdigital Technology Coporation | Multiple impulse excitation speech encoder and decoder |
| CN1328682A (en) * | 1998-10-27 | 2001-12-26 | 沃斯艾格公司 | Perceptual weighting device and method for efficient coding of wideband signals |
| CN1711736A (en) * | 2002-10-08 | 2005-12-21 | M/A-Com公司 | Apparatus, methods and articles of manufacture for pre-emphasis filtering of a modulated signal |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6006174A (en) * | 1990-10-03 | 1999-12-21 | Interdigital Technology Coporation | Multiple impulse excitation speech encoder and decoder |
| CN1328682A (en) * | 1998-10-27 | 2001-12-26 | 沃斯艾格公司 | Perceptual weighting device and method for efficient coding of wideband signals |
| CN1711736A (en) * | 2002-10-08 | 2005-12-21 | M/A-Com公司 | Apparatus, methods and articles of manufacture for pre-emphasis filtering of a modulated signal |
Non-Patent Citations (2)
| Title |
|---|
| YANG Yuhong,et al..Analysis and application of perceptual weighting for AVS-M audio coder.《International Conference on Wireless Communications, Networking and Mobile Computing, 2007, WiCom 2007》.2007,2923-2926. * |
| 李文广等.低码率语音编码中感知加权滤波器的一种新型算法.《上海交通大学学报》.1998,第32卷(第6期),38-42. * |
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