Method for automatically searching peak of energy spectrum at given position

Abstract

The invention provides an automatic peak searching method for an energy spectrum at a given position, which can be applied to the technical field of energy spectrum signal processing. The method comprises the following steps: calculating an initial first-order derivative and an initial second-order derivative of an energy spectrum signal, and carrying out smoothing processing to obtain a smoothed first-order derivative and a smoothed second-order derivative; based on the first-order derivative and the second-order derivative, starting from a given position in the energy spectrum signal, determining a lower boundary of the target area towards the left side and determining an upper boundary of the target area towards the right side, searching for a leftmost position in which a corresponding first derivative is greater than a first threshold value towards the left side and a rightmost position in which a corresponding first derivative is less than a second threshold value towards the right side, respectively, and searching for the number of positions in which the absolute value of a corresponding second derivative searched between the leftmost position and the rightmost position is less than a third threshold value, determining the leftmost position as a lower boundary and determining the rightmost position as an upper boundary; and determining peak information based on the target region.

Description

Technical Field

[0001] At least one embodiment of the present invention relates to the field of energy spectrum information processing technology, and more specifically to a method for automatic peak finding of energy spectrum at a given location. Background Technology

[0002] In the field of spectrometers, a common method for automatically determining the ROI (Region of Interest) and calculating peak information by finding possible peaks around a given location is to use a fixed window to select the ROI. However, this method has low peak information extraction accuracy and may not be able to completely select the ROI of the peak. Summary of the Invention

[0003] In view of the above problems, the present invention provides a method for automatically finding peaks in the energy spectrum at a given position to improve the accuracy of peak range calculation.

[0004] According to a first aspect of the present invention, a method for automatic peak finding of an energy spectrum at a given position is provided. The method includes: calculating an initial first derivative and an initial second derivative of an energy spectrum signal, and performing smoothing processing to obtain smoothed first and second derivatives; based on the first and second derivatives, determining the lower boundary of a target region to the left and the upper boundary of the target region to the right, starting from a given position in the energy spectrum signal, including: searching for the leftmost position where the corresponding first derivative is greater than a first threshold and searching for the rightmost position where the corresponding first derivative is less than a second threshold, starting from the given position; determining the leftmost position as the lower boundary and the rightmost position as the upper boundary based on the fact that the number of positions where the absolute value of the corresponding second derivative is less than a third threshold found between the leftmost and rightmost positions is 2; and determining the peak information of the target region based on the target region defined by the lower and upper boundaries.

[0005] According to an embodiment of the present invention, the method further includes: increasing the sampling density of the second derivative when the number of positions where the absolute value of the corresponding second derivative is less than the third threshold between the leftmost position and the rightmost position is less than 2.

[0006] According to an embodiment of the present invention, increasing the sampling density of the second derivative includes interpolating the second derivative.

[0007] According to an embodiment of the present invention, the above method further includes: determining the position where the absolute value of the corresponding second derivative is less than a third threshold by performing linear fitting on the second derivative.

[0008] According to an embodiment of the present invention, the method further includes: if the number of positions between the leftmost position and the rightmost position where the absolute value of the corresponding second derivative is less than the third threshold is greater than 2, adjusting the first threshold and / or the second threshold until the number of positions between the leftmost position and the rightmost position where the absolute value of the corresponding second derivative is less than the third threshold is equal to 2.

[0009] According to an embodiment of the present invention, the method further includes: dynamically adjusting at least one of the sampling density increase factors of the first threshold, the second threshold, the third threshold, and the second derivative based on the signal noise.

[0010] According to an embodiment of the present invention, the method further includes: updating the given position when the first derivative at the given position is less than or equal to the first threshold and greater than or equal to the second threshold, and the absolute value of the second derivative at the given position is less than or equal to twice the first threshold.

[0011] According to an embodiment of the present invention, the absolute values ​​of the first threshold and the second threshold are equal, and the first threshold is greater than the second threshold.

[0012] According to an embodiment of the present invention, the above smoothing process includes: smoothing the initial first derivative and initial second derivative of the energy spectrum signal using an interpolation method and a smoothing method.

[0013] According to embodiments of the present invention, the above interpolation method includes a cubic spline interpolation method, and the above smoothing method includes a locally weighted scatter smoothing method.

[0014] According to an embodiment of the present invention, a seed point growth strategy is determined based on a given position in the energy spectrum signal, and the lower and upper boundaries of the target region are searched to the left and right respectively starting from the given position. A third threshold is set in the region of zero of the second derivative, and the third threshold is used to... Replacing the judgment of the second derivative being equal to zero with a threshold range allows for more accurate execution of the seed point growth strategy. By combining the characteristics of the first and second derivatives of the energy spectrum signal output by the spectrometer, and based on zero-point region detection and the seed point growth strategy, the lower and upper boundaries of the target region at a given location are determined. This enables precise localization of the ROI region of the peak where the seed point is located, ensuring that the ROI region contains the complete peak signal. This improves the completeness and accuracy of peak region localization, avoids missed or false detections, and achieves accurate capture and extraction of peak information. Attached Figure Description

[0015] The above-described features, other objects, and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0016] Figure 1 A flowchart of a fixed-window-based ROI determination method in related technologies is shown;

[0017] Figure 2 A flowchart illustrating the operation of an automatic peak finding method for a given position energy spectrum according to an embodiment of the present invention is shown.

[0018] Figure 3 A schematic diagram of a seed point growth strategy according to an embodiment of the present invention is shown. Detailed Implementation

[0019] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the invention for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0020] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0021] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0022] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0023] Figure 1 A flowchart of a fixed-window-based ROI determination method in related technologies is shown.

[0024] like Figure 1As shown, the fixed-window-based ROI determination method includes two scenarios: "with energy calibration" and "without energy calibration." Energy calibration represents the correspondence between energy and channel address. When the spectrometer has completed energy and peak calibration, the full width at half maximum (FWHM) of the peak at a given position is calculated; "n × FWHM" is determined as the width of the ROI, where n is an integer; symmetrically expanding outwards from the given position with a width of "ROI / 2" from the given position, the lower and upper limits of the ROI are obtained. When the spectrometer has not completed energy calibration, a fixed value is set as the width of the ROI; symmetrically expanding outwards from the given position with a width of "ROI / 2" from the given position, the lower and upper limits of the ROI are obtained.

[0025] The fixed-window-based ROI determination method has the following technical problems:

[0026] (1) The ROI width design is unreasonable in the "no energy calibration" scenario. When the spectrometer has not completed energy calibration, using a fixed-width ROI without dynamically adjusting it according to the actual peak width will lead to large errors. If the peak width is set too large, the ROI will contain a lot of irrelevant signals, resulting in errors in peak information calculation; if the peak width is set too small, the ROI cannot cover the complete peak shape, resulting in the loss of peak features.

[0027] (2) Insufficient robustness in handling overlapping peaks and weak peaks. Both the "with energy scale" and "without energy scale" scenarios generate symmetrical ROIs based on the assumption that the given position is the center of the peak, without considering the case of overlapping peaks (multiple adjacent peaks): if the given position falls in the transition region of two overlapping peaks, the ROI will contain some features of both peaks at the same time, resulting in confusion in the calculation of peak information.

[0028] (3) Failure to consider peak asymmetry leads to incomplete ROI coverage. Peaks in actual spectrometer signals often exhibit asymmetry due to instrument response functions, sample matrix effects, etc., such as steep leading edges or trailing edges. Expanding the peak symmetrically to the left and right with a width of "ROI / 2" will result in: the wider side of the peak being truncated; and the narrower side of the peak including too much irrelevant signal, interfering with the calculation of parameters such as peak area and peak height.

[0029] This invention provides a method for automatic peak finding of energy spectrum at a given location, in order to solve at least one of the above-mentioned technical problems.

[0030] Figure 2 A flowchart illustrating the operation of a method for automatic peak finding of energy spectrum at a given location according to an embodiment of the present invention is shown.

[0031] like Figure 2 As shown, the method for automatically finding peaks in the energy spectrum at a given location includes operations S210 to S230.

[0032] In operation S210, the initial first and second derivatives of the energy spectrum signal are calculated and smoothed to obtain the smoothed first and second derivatives.

[0033] In one example, the energy spectrum signal could be a gamma energy spectrum signal. The energy spectrum signal can be obtained from a file or from energy spectrum data acquired from the device to obtain valid analytical data.

[0034] In operation S210, based on the first and second derivatives, starting from a given position in the energy spectrum signal, the lower boundary of the target region is determined to the left and the upper boundary of the target region is determined to the right, respectively. This includes: starting from the given position, searching to the left for the leftmost position where the corresponding first derivative is greater than a first threshold and searching to the right for the rightmost position where the corresponding first derivative is less than a second threshold. Based on the fact that the number of positions between the leftmost and rightmost positions where the absolute value of the corresponding second derivative is less than a third threshold is 2, the leftmost position is determined as the lower boundary and the rightmost position is determined as the upper boundary.

[0035] In one embodiment, a given position represents any location within a specified energy spectrum signal. Starting from a given position, such as one specified by the user or automatically identified through image processing, the given position can be an index position near the target peak, also known as a seed point, and can be an integer. When the given seed point is an integer, directly detecting a position where the corresponding second derivative is zero numerically will almost never yield a search result. A third threshold is set in the region of zero second derivative. ,For example, The third threshold It can represent a local minimum, approaching 0. Among them, This represents the seed point.

[0036] In operation S230, the peak information of the target region is determined based on the target region defined by the lower and upper boundaries. Linear fitting can be used to calculate the peak information contained within the target region.

[0037] According to an embodiment of the present invention, the target region, i.e. the ROI region where the seed point is located, can determine the upper and lower channel addresses to be analyzed based on the energy scale of the spectrometer and the ROI region, thereby solving the peak information.

[0038] According to an embodiment of the present invention, a seed point growth strategy is determined based on a given position in the energy spectrum signal, and the lower and upper boundaries of the target region are searched to the left and right respectively starting from the given position. A third threshold is set in the region of zero of the second derivative, and the third threshold is used to... Replacing the judgment of the second derivative being equal to zero with a threshold range allows for more accurate execution of the seed point growth strategy. By combining the characteristics of the first and second derivatives of the energy spectrum signal output by the spectrometer, and based on zero-point region detection and the seed point growth strategy, the lower and upper boundaries of the target region at a given location are determined. This enables precise localization of the ROI region of the peak where the seed point is located, ensuring that the ROI region contains the complete peak signal. This improves the completeness and accuracy of peak region localization, avoids missed or false detections, and achieves accurate capture and extraction of peak information.

[0039] According to an embodiment of the present invention, the smoothing process may include: smoothing the initial first derivative and initial second derivative of the energy spectrum signal using an interpolation method and a smoothing method.

[0040] To address the high-frequency noise, sharp peaks, and rapidly changing trends in the initial first and second derivatives of energy spectrum signals, interpolation and smoothing methods are used to smooth the initial first and second derivatives, which can improve the accuracy of feature extraction from the first and second derivatives.

[0041] According to an embodiment of the present invention, the interpolation method may be a cubic spline interpolation method. The smoothing method may be a locally weighted scatter smoothing method.

[0042] By employing cubic spline interpolation, the sampling density of the first and second derivatives can be increased through high-density interpolation. Using a locally weighted scatter smoothing method, noise of different frequencies can be adaptively suppressed by weighted fitting of local data points without destroying the peak characteristics of the signal. Combining cubic spline interpolation and locally weighted scatter smoothing to smooth the initial first and second derivatives of the energy spectrum signal effectively suppresses noise while preserving the peak and trend details of the first and second derivatives. This reduces the interference of residual noise on the detection of zero-point regions of the second derivative, improving the accuracy of feature extraction from the first and second derivatives.

[0043] According to the method for automatic peak finding at a given position energy spectrum according to the embodiments of the present invention, by setting a continuous region screening logic that requires the derivative features of the peak region to continuously meet the search conditions, isolated false points caused by noise can be effectively eliminated. For example, for the detection of weak peaks, the weak derivative features of weak peaks can be captured by zero-point region detection and seed point growth strategy to avoid missed detection.

[0044] In one example, the interpolation method can also be linear interpolation. Linear interpolation has lower computational cost and can be used in scenarios with high real-time requirements, but its interpolation smoothness is lower. The interpolation method can also be cubic interpolation. Cubic interpolation has better smoothness than linear interpolation, but its computational cost is slightly higher than cubic spline interpolation. The appropriate interpolation method can be selected based on the spectrometer's real-time and accuracy requirements.

[0045] In one example, the smoothing method could also be Gaussian filtering. Gaussian filtering allows for control of the smoothing degree by setting a standard deviation parameter, and is suitable for spectrometer signals with relatively uniform noise distribution. An appropriate smoothing method can be selected based on the signal noise characteristics.

[0046] Based on the given position in the energy spectrum signal, the seed point growth strategy is determined using the first and second derivatives.

[0047] According to an embodiment of the present invention, the absolute values ​​of the first threshold and the second threshold can be equal, and the first threshold is greater than the second threshold. The first threshold can be used... This means that the second threshold can be used It means that, among them, It is a positive number.

[0048] In one example, given a location first derivative And the second derivative That is, the first derivative In the ascending phase. From a given position Begin, towards the given position The leftmost position corresponding to the first derivative being greater than the first threshold is searched on the left. Towards a given position The right side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. First position Towards the first position On the right, a second corresponding second derivative whose absolute value is less than the third threshold can be found. Second position Towards the second position The rightmost position corresponding to the first derivative being less than the second threshold is searched. Based on the first leftmost position and the first rightmost position The absolute value of the corresponding second derivative found between the two is less than the third threshold. The number of positions is 2. Identified as a Region of Interest (ROI), used to calculate a given location. Peak information for the region.

[0049] Figure 3 A schematic diagram of a seed point growth strategy according to an embodiment of the present invention is shown.

[0050] like Figure 3 As shown, the horizontal axis represents time, and the vertical axis represents amplitude. Figure 3 (a) in the diagram represents a schematic representation of the energy spectrum signal. Figure 3 (b) in the diagram represents the first derivative after processing with cubic spline interpolation and Lowess smoothing (locally weighted scatter smoothing). Figure 3 In the diagram, (c) represents a schematic representation of the second derivative after cubic spline interpolation and Lowess smoothing. For example... Figure 3 As shown in (b), the first threshold Second threshold Approaching zero.

[0051] In one example, such as Figure 3 As shown, given position First derivative of (seed point) And the second derivative That is, the first derivative In the descending zone. From a given position Begin, towards the given position The left side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The third position Towards the third position The leftmost position corresponding to the first derivative being greater than the first threshold is searched. Towards a given position The right side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The fourth position Towards the fourth position The rightmost position corresponding to the first derivative being less than the second threshold is searched. Based on the second leftmost position Second rightmost position The absolute value of the corresponding second derivative found between the two is less than the third threshold. The number of positions is 2. Identified as a Region of Interest (ROI), used to calculate a given location. Peak information for the region.

[0052] In one example, given a location first derivative And the second derivative That is, the first derivative In the ascending phase. From a given position Begin, towards the given position The left side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The fifth position Towards the fifth position To the left of the first threshold, we can find the second corresponding second derivative whose absolute value is less than the third threshold. The sixth position Towards the sixth position The leftmost position of the search for the corresponding first derivative is greater than the first threshold. Towards a given position The rightmost position of the search for the corresponding first derivative is less than the second threshold. Based on the third leftmost position and the third rightmost position The absolute value of the corresponding second derivative found between the two is less than the third threshold. The number of positions is 2. Identified as a Region of Interest (ROI), used to calculate a given location. Peak information for the region.

[0053] In one example, given a location first derivative And the second derivative That is, the first derivative In the descending zone. From a given position Begin, towards the given position The left side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The seventh position Towards the seventh position The leftmost position of the search is the position where the first derivative is greater than the first threshold. Towards a given position The right side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The eighth position Towards the eighth position The rightmost position of the search for the corresponding first derivative is less than the second threshold. Based on the fourth leftmost position and the fourth rightmost position The absolute value of the corresponding second derivative found between the two is less than the third threshold. The number of positions is 2. Identified as a Region of Interest (ROI), used to calculate a given location. Peak information for the region.

[0054] In one example, given a location first derivative Less than or equal to the first threshold And greater than or equal to the second threshold , that is Given position The second derivative The absolute value is greater than the first threshold. Twice, indicating a given position Approaching the peak point. From a given position. Begin, towards the given position The left side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The ninth position Towards the ninth position The leftmost position of the search for the corresponding first derivative greater than the first threshold is the fifth position. Towards a given position The right side can be searched to find the first corresponding second derivative whose absolute value is less than the third threshold. The tenth position Towards the tenth position The rightmost position of the search for the corresponding first derivative is less than the second threshold. Based on the fifth position on the far left. and the fifth position on the far right The absolute value of the corresponding second derivative found between the two is less than the third threshold. The number of positions is 2. Identified as a Region of Interest (ROI), used to calculate a given location. Peak information for the region.

[0055] In one example, according to an embodiment of the invention, a given position first derivative Less than or equal to the first threshold and greater than or equal to the second threshold , that is Given position The second derivative The absolute value is less than or equal to the first threshold. Twice, indicating a given position If there are no peak points in the region, a prompt can be made indicating that peak fitting cannot be performed, and the given position can be updated.

[0056] According to an embodiment of the present invention, if the number of positions where the absolute value of the corresponding second derivative is less than the third threshold between the leftmost and rightmost positions is less than 2, the accuracy of the search can be improved by increasing the sampling density of the second derivative.

[0057] According to embodiments of the present invention, increasing the sampling density of the second derivative may include interpolating the second derivative. By performing high-density interpolation on the curve of the second derivative, a finer continuous curve is generated.

[0058] According to an embodiment of the present invention, the location where the absolute value of the corresponding second derivative is less than a third threshold is determined by performing linear fitting on the second derivative. By performing linear fitting on the zero-point region of the second derivative, the calculation accuracy of the location (zero-point location) where the absolute value of the corresponding second derivative is less than the third threshold can be improved.

[0059] According to an embodiment of the present invention, discrete zero-point detection is transformed into continuous region localization by "region search + fine interpolation", which can solve the problem of non-zero second derivative at integer positions and improve the localization accuracy to the level of interpolation multiple. This can significantly improve the localization accuracy of zero points with second derivative and provide accurate reference points for subsequent ROI growth.

[0060] According to an embodiment of the present invention, if the number of positions between the leftmost and rightmost positions where the absolute value of the corresponding second derivative is less than the third threshold is greater than 2, the first threshold and / or the second threshold can be adjusted until the number of positions between the leftmost and rightmost positions where the absolute value of the corresponding second derivative is less than the third threshold is equal to 2.

[0061] The automatic peak finding method for energy spectrum at a given position in this invention can effectively handle overlapping peaks and improve adaptability to complex spectra. If the number of positions where the absolute value of the corresponding second derivative is less than the third threshold between the leftmost and rightmost positions is greater than 2, it indicates that there are overlapping peaks between the leftmost and rightmost positions. Overlapping peaks can be separated by increasing the first threshold and / or decreasing the second threshold (e.g., by increasing m) and re-searching. Effective handling of overlapping peaks makes this method applicable to the spectral analysis of complex multi-element samples, expanding the application range of the spectrometer.

[0062] If there is a clear interval between two peaks at the leftmost and rightmost positions, they can be identified as two independent peaks, thus achieving the separation of overlapping peaks.

[0063] According to an embodiment of the present invention, the method for automatically finding peaks in the energy spectrum at a given location further includes: dynamically adjusting at least one of the sampling density increase factors of the first threshold, the second threshold, the third threshold, and the second derivative based on the signal noise.

[0064] For example, the first threshold can be adaptively adjusted based on the dynamic calculation of the signal noise level, which can be used in scenarios with large noise fluctuations, further improving the anti-interference capability of the automatic peak finding method of energy spectrum at a given location in the embodiments of the present invention.

[0065] According to an embodiment of the present invention, the first threshold and the second threshold related to the first derivative, the third threshold related to the second derivative, the sampling density increase factor of the second derivative, etc. are set as adjustable dynamic parameters. The threshold can be adaptively adjusted according to the noise level, the threshold can be adaptively adjusted according to the signal characteristics of different spectrometers, and the threshold can be adaptively adjusted according to the signal intensity of different samples.

[0066] The automatic peak finding method for a given energy spectrum at a given location, as described in this invention, exhibits strong parameter adaptability. It can be adapted to different scenarios by simply adjusting the threshold values. For example, for mass spectrometry signals with high signal intensity and low noise, the first threshold can be decreased (while the second and third thresholds are increased) to improve positioning accuracy. Conversely, for X-ray fluorescence signals with low signal intensity and high noise, the first threshold can be increased (while the second and third thresholds are decreased) to enhance anti-interference capabilities.

[0067] The method for automatically finding peaks at a given location in the energy spectrum of this invention adopts the setting of a first threshold and a second threshold related to the first derivative, and a third threshold related to the second derivative. The upper and lower limits of the ROI are defined by comparing the first derivative with the thresholds, which can improve the completeness of the ROI range of peaks near the seed point.

[0068] The automatic peak finding method for a given energy spectrum in this invention employs a "second derivative zero-point region detection + fine interpolation" technique. It searches for continuous zero-point regions, then performs high-density interpolation on these regions, finding the point closest to zero on the interpolated continuous signal as the precise zero. By transforming "point detection" into "region detection" and converting discrete regions into continuous signals through high-density interpolation, the zero-point location of the second derivative can be determined with high precision.

[0069] The method for automatic peak finding at a given position in the energy spectrum of this invention can be applied to the given position peak finding algorithm based on seed point growth in the gamma energy spectrum of a high-purity germanium spectrometer. It can accurately locate the characteristic peak positions in the spectrum and provide reliable peak data support for subsequent applications such as material composition analysis and content detection.

[0070] Those skilled in the art will understand that the features described in the various embodiments of the present invention can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention can be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.

[0071] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. A method for automatically finding peaks in an energy spectrum at a given location, characterized in that, The method includes: Calculate the initial first and second derivatives of the energy spectrum signal, and then smooth it to obtain the smoothed first and second derivatives. Based on the first and second derivatives, starting from a given position in the energy spectrum signal, the lower boundary of the target region is determined to the left and the upper boundary of the target region is determined to the right, including: Starting from the given position, search for the leftmost position where the first derivative is greater than the first threshold to the left, and search for the rightmost position where the first derivative is less than the second threshold to the right. Based on the fact that the number of positions where the absolute value of the corresponding second derivative is less than the third threshold between the leftmost and rightmost positions is 2, the leftmost position is determined as the lower boundary and the rightmost position is determined as the upper boundary; and Based on the target region defined by the lower boundary and the upper boundary, the peak information of the target region is determined.

2. The method according to claim 1, characterized in that, The method further includes increasing the sampling density of the second derivative if the number of positions where the absolute value of the corresponding second derivative is less than the third threshold between the leftmost position and the rightmost position is less than 2.

3. The method according to claim 2, characterized in that, The increase in the sampling density of the second derivative includes: Interpolate the second derivative.

4. The method according to claim 1, characterized in that, The method further includes: determining the position where the absolute value of the corresponding second derivative is less than a third threshold by performing linear fitting on the second derivative.

5. The method according to claim 1, characterized in that, The method further includes: if the number of positions between the leftmost position and the rightmost position where the absolute value of the corresponding second derivative is less than the third threshold is greater than 2, adjusting the first threshold and / or the second threshold until the number of positions between the leftmost position and the rightmost position where the absolute value of the corresponding second derivative is less than the third threshold is equal to 2.

6. The method according to claim 2, characterized in that, The method further includes: Based on the signal noise, at least one of the sampling density increase factors of the first threshold, the second threshold, the third threshold, and the second derivative is dynamically adjusted.

7. The method according to claim 1, characterized in that, The method further includes updating the given position when the first derivative at the given position is less than or equal to the first threshold and greater than or equal to the second threshold, and the absolute value of the second derivative at the given position is less than or equal to twice the first threshold.

8. The method according to claim 1, characterized in that, The absolute values ​​of the first threshold and the second threshold are equal, and the first threshold is greater than the second threshold.

9. The method according to claim 1, characterized in that, The smoothing process includes: The initial first and second derivatives of the energy spectrum signal are smoothed using interpolation and smoothing methods.

10. The method according to claim 9, characterized in that, The interpolation method includes cubic spline interpolation, and the smoothing method includes locally weighted scatter smoothing.

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