Single-pixel image reconstruction method and system capable of resisting ambient light interference

Abstract

The invention provides a single-pixel image reconstruction method and system resistant to ambient light interference, and relates to the technical field of optical imaging and image processing. Comprising the following steps: acquiring an original detection value of a single-pixel imaging system target scene modulation signal; performing numerical fitting on the original detection value to obtain an ambient light change curve; calculating a mean value of all data in the original detection value to obtain signal average intensity; designing an optimization formula based on the ambient light change curve, the signal average intensity and the original detection value, and performing ambient light removal on the original detection value to obtain a detection value after ambient light suppression; and obtaining a restored image of the target scene by adopting an image reconstruction algorithm based on the detection value after the ambient light is suppressed. According to the invention, the ambient light removal algorithm is introduced, ambient light removal is carried out on the modulated detection value, and then the image is reconstructed, so that even if significant ambient light change exists in the imaging process, the high-quality reconstructed image can be obtained, and the actual application range of the single-pixel imaging technology is expanded.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical imaging and image processing, and in particular relates to a single-pixel image reconstruction method and system that is resistant to ambient light interference. Background Art

[0002] The single-pixel imaging system uses a single-pixel sensor to replace the traditional array imaging detector, actively or passively generates different coding patterns to encode the target scene, and uses the corresponding reconstruction algorithm to process the detection data of the single-pixel sensor to complete the image reconstruction of the target scene. Single-pixel imaging uses a single-pixel detector without spatial resolution to achieve two-dimensional imaging, which has the advantages of high sensitivity and low cost, and has good application prospects in spectral imaging, three-dimensional imaging, ultrafast imaging, terahertz imaging, etc.

[0003] Since the current domestic research on single-pixel imaging technology mainly adopts different schemes to improve the restoration accuracy of single-pixel imaging systems, it is usually necessary to obtain high-quality reconstructed images under conditions with low background noise, such as fiber optic collection, optical shielding and collimation. These conditions are relatively harsh and not conducive to practical applications. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the present invention provides a single-pixel image reconstruction method and system that are resistant to ambient light interference. By introducing an ambient light removal algorithm, the modulated detection value is subjected to ambient light removal, and then the image is reconstructed. Even if there are significant ambient light changes during the imaging process, a high-quality reconstructed image can be obtained, thereby expanding the practical application scope of single-pixel imaging technology.

[0005] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0006] A first aspect of the present invention provides a single-pixel image reconstruction method that is resistant to ambient light interference.

[0007] A single-pixel image reconstruction method resistant to ambient light interference comprises the following steps:

[0008] Obtaining the original detection value of the target scene modulation signal of the single-pixel imaging system;

[0009] Perform numerical fitting on the original detection value to obtain the ambient light change curve;

[0010] Calculate the mean of all data in the original detection value to obtain the average signal strength;

[0011] Based on the ambient light change curve, the average signal intensity and the original detection value, an optimization formula is designed to remove the ambient light from the original detection value to obtain the detection value after suppressing the ambient light;

[0012] Based on the detection value after suppressing the ambient light, an image reconstruction algorithm is used to obtain the restored image of the target scene.

[0013] A second aspect of the present invention provides a single-pixel image reconstruction system that is resistant to ambient light interference.

[0014] A single-pixel image reconstruction system that is resistant to ambient light interference, including:

[0015] The data acquisition module is configured to: acquire the original detection value of the target scene modulation signal of the single pixel imaging system;

[0016] The numerical fitting module is configured to: perform numerical fitting on the original detection value to obtain an ambient light change curve;

[0017] The mean value calculation module is configured to: calculate the mean value of all data in the original detection value to obtain the average signal strength;

[0018] The optimization removal module is configured to: design an optimization formula based on the ambient light change curve, the average signal intensity and the original detection value, remove the ambient light from the original detection value, and obtain the detection value after suppressing the ambient light;

[0019] The image reconstruction module is configured to: obtain a restored image of the target scene using an image reconstruction algorithm based on the detection value after suppressing the ambient light.

[0020] A third aspect of the present invention provides a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the steps in the single-pixel image reconstruction method for resisting ambient light interference as described in the first aspect of the present invention.

[0021] The fourth aspect of the present invention provides an electronic device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in the single-pixel image reconstruction method resistant to ambient light interference as described in the first aspect of the present invention are implemented.

[0022] One or more of the above technical solutions have the following beneficial effects:

[0023] The present invention provides a single-pixel image reconstruction method and system that is resistant to ambient light interference in a high-noise environment with significant ambient light interference, so as to achieve high-quality imaging and expand the application scenarios of single-pixel imaging technology: by numerically fitting the original detection value, an ambient light change curve is obtained, the mean of all data in the original detection value is calculated, and the signal average intensity is obtained. Based on the ambient light change curve, the signal average intensity and the original detection value, an optimization formula is designed to remove ambient light from the original detection value to obtain the detection value after suppressing ambient light, and then an image reconstruction algorithm is used to obtain a restored image of the target scene. The present invention removes ambient light from the modulated detection value and then reconstructs the image. By introducing the ambient light removal algorithm, a high-quality reconstructed image can be obtained even if there is a significant ambient light change during the imaging process.

[0024] The present invention allows a single-pixel imaging system to collect detection values ​​under significant ambient light interference, and by performing anti-ambient light interference processing on the detection values, a high-quality reconstructed image can be obtained using a standard reconstruction algorithm.

[0025] The present invention enables the single-pixel imaging system to have a stronger performance in resisting ambient light interference without the need for hardware modification, and has a higher practical application value.

[0026] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0028] Figure 1 This is an overall flow chart of Embodiment 1 of the present invention.

[0029] Figure 2 Schematic diagram of the single-pixel imaging system experimental system.

[0030] Figure 3 is the original detection value U in the test.

[0031] Figure 4 The ambient light change curve Y1 and the average signal intensity in the test

[0032] Figure 5 It is the detection value Y2 after suppressing the ambient light in the test.

[0033] Figure 6 This is the image reconstructed using the detection value Y2 after suppressing ambient light in the test.

[0034] Figure 7 is the image reconstructed using the original detection value Y in the test. DETAILED DESCRIPTION

[0035] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0036] It should be noted that the terms used herein are for describing specific embodiments only and are not intended to be limiting of exemplary embodiments according to the present invention.

[0037] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0038] Embodiment 1

[0039] Classic single-pixel imaging requires that the ambient light remain stable during the imaging process, otherwise the reconstructed image will have serious noise or even fail to be reconstructed. Currently, the condition for maintaining light stability is relatively harsh and not conducive to practical applications. Based on this, the embodiment of the present invention utilizes the property that the average modulation amplitude of the single-pixel modulation matrix is ​​one-half, removes the ambient light from the modulated detection value, and then reconstructs the image. By introducing the ambient light removal algorithm, a high-quality reconstructed image can be obtained even if there are significant changes in ambient light during the imaging process.

[0040] The purpose of the embodiments of the present invention is to provide a single-pixel image reconstruction method that is resistant to ambient light interference, so as to achieve high-quality imaging of a target scene under conditions of ambient light interference. Figure 1 As shown, the single-pixel image reconstruction method for resisting ambient light interference may include the following steps:

[0041] Obtaining the original detection value of the target scene modulation signal of the single-pixel imaging system;

[0042] Perform numerical fitting on the original detection value to obtain the ambient light change curve;

[0043] Calculate the mean of all data in the original detection value to obtain the average signal strength;

[0044] Based on the ambient light change curve, the average signal intensity and the original detection value, an optimization formula is designed to remove the ambient light from the original detection value to obtain the detection value after suppressing the ambient light;

[0045] Based on the detection value after suppressing the ambient light, an image reconstruction algorithm is used to obtain the restored image of the target scene.

[0046] More specifically, this embodiment includes the following steps:

[0047] S1. Generate a measurement matrix according to the resolution and sampling compression ratio;

[0048] The classic single-pixel imaging system is used for imaging to obtain the original detection value of the modulation signal of the target scene;

[0049] S2, performing algorithm processing on the original detection value to resist the interference of ambient light;

[0050] S3. Using an image reconstruction algorithm to calculate the processing result obtained in step S2, to obtain a restored image.

[0051] Furthermore, in step S1, a measurement matrix is ​​generated according to the resolution size and the sampling compression ratio. The specific process is: if the resolution size is N×N and the sampling rate is P%, it is necessary to generate M N×N dimensional measurement matrices, M=P%×N×N, and finally generate a random matrix φ with a dimension of M×N×N using a random binary method.

[0052] The matrix is ​​loaded into the single-pixel system and a round of encoding is completed to obtain the original detection value Y.

[0053] Further, step S2 is specifically:

[0054] The original detection value Y is numerically fitted to obtain the ambient light change curve Y1;

[0055] Common fitting algorithms can be selected, including but not limited to Gaussian fitting, polynomial fitting, nonlinear least squares fitting, etc.

[0056] The average value of all data in the original detection value Y is calculated to obtain the average signal strength.

[0057] Use the designed optimization formula The detection value Y2 after suppressing the ambient light is obtained.

[0058] The optimization formula is as follows:

[0059]

[0060] Among them, Y is the original detection value; Y1 is the ambient light change curve; is the average signal intensity; Y2 is the detection value after suppressing ambient light.

[0061] Further, step S3 is specifically as follows:

[0062] The random matrix φ and the detection value Y2 after suppressing ambient light are input into the image reconstruction algorithm to obtain a high-quality reconstructed image. The specific data processing process is as follows: Taking TVAL3 in the compressed sensing algorithm as an example, the input of the algorithm is two items, one is the detection value Y2 after suppressing ambient light, and the other is the random matrix φ. The output is the reconstructed image. Here, Y2 is not processed and directly input into the algorithm. The M×N×N dimensional matrix φ needs to be reshaped to M×N 2 Dimensional re-input algorithm, each N×N dimensional matrix is ​​reshaped into 1×N 2 Dimension, placed in M×N 2 dimensional matrix, rows 1 to M.

[0063] This embodiment allows a single-pixel imaging system to collect detection values ​​under significant ambient light interference, and by performing anti-ambient light interference processing on the detection values, a high-quality reconstructed image can be obtained using a standard reconstruction algorithm. This embodiment enables a single-pixel imaging system to have strong anti-ambient light interference performance without hardware modification, and has high practical application value.

[0064] The technical solution of this embodiment will be further described below in conjunction with relevant drawings.

[0065] like Figure 2 As shown, this embodiment uses a single-pixel imaging system to perform single-pixel imaging on the target scene, and uses a single-pixel imaging method that is resistant to ambient light interference to process the data. The process is as follows Figure 1 As shown, the details are as follows:

[0066] The target scene uses a single-pixel imaging system to collect the original detection value Y (such as Figure 3 As shown). The single pixel imaging system may use but is not limited to active or passive imaging methods, and the modulation device is not limited to DMD, SLM, and mask.

[0067] This embodiment first generates a measurement matrix according to the resolution and sampling compression ratio; then loads the measurement matrix into the single-pixel imaging system, and obtains the original detection value Y after completing a round of encoding. The specific processing process here is:

[0068] If the resolution is N×N and the sampling rate is P%, then M measurement matrices need to be generated, M=P%×N×N, and the random binary method can be used to finally generate a random matrix φ with a dimension of M×N×N. If the modulation device is a DMD, then it is only necessary to load the random matrix φ into the memory; if the modulation device is a mask, it can be loaded by coating. Use the corresponding system to complete the encoding to obtain the original detection value Y.

[0069] The above process of loading the random matrix φ into the single-pixel imaging system and encoding to obtain the original detection value Y is a prior art and will not be described in detail here.

[0070] The detection value Y is further processed using the method of the present invention, and the processing steps include:

[0071] like Figure 4 As shown by the red line in FIG, the original detection value Y is data fitted to obtain the ambient light change curve Y1. Common fitting algorithms can be selected, including but not limited to Gaussian fitting, polynomial fitting, nonlinear least squares fitting, etc. This embodiment shows the result of 5th order polynomial fitting.

[0072] The average signal strength is obtained by averaging all the original detection values ​​Y.

[0073] like Figure 5 As shown, using the optimization formula The detection value Y2 after suppressing the ambient light is obtained.

[0074] Finally, the random matrix φ and the optimized detection value Y2 are combined and input into the image reconstruction algorithm to complete the calculation and obtain the optimized reconstructed image, as shown in Figure 6 Common image reconstruction algorithms can be selected, including but not limited to compressed sensing algorithm, differential ghost imaging method, neural network algorithm, etc.

[0075] This embodiment uses the compressed sensing TVAL3 algorithm in the above image reconstruction algorithm. The specific data processing flow is as follows: the input of the algorithm is two items, one is the detection value Y2 after suppressing ambient light, and the other is the random matrix φ, and the output is the reconstructed image. Here, Y2 is not processed and directly input into the algorithm. The M×N×N dimensional matrix φ needs to be reshaped to M×N 2 Dimensional re-input algorithm, each N×N dimensional matrix is ​​reshaped into 1×N 2 Dimension, placed in M×N 2 In addition to the 1 to M rows of the dimensional matrix, you can also set the maximum number of iterations of the algorithm and other basic settings as needed.

[0076] Here, the process of using the compressed sensing TVAL3 algorithm to process the detection value Y2 and the random matrix φ after suppressing the ambient light to finally obtain the reconstructed image is a prior art and will not be elaborated in detail in this embodiment.

[0077] like Figure 2 As shown, the experimental details of the data in this embodiment are:

[0078] For an imaging resolution of 64×64 and a sampling rate of 50%, 2048 64×64 random matrices are constructed. In a single-pixel imaging system, LED is used as the light source, and DMD is used to complete the projection. The light source irradiates the DMD, and the reflected light is imaged onto object E (black background with white text placed horizontally) through the lens. The light reflected by the object is converged to the detector through the lens for photoelectric conversion. The data acquisition card converts the electrical signal output by the detector into a digital signal and imports it into the PC. Combined with the reconstruction algorithm, the image is reconstructed. This embodiment uses a shaking flashlight to simulate ambient light interference, and the reconstruction adopts the classic TVAL3 algorithm in the compressed sensing algorithm. Figure 7 As shown, the original detection value Y is input into the image reconstruction algorithm to obtain the original image, which is compared with the method described in this embodiment.

[0079] The comparison results are:

[0080] From the imaging results, compared Figure 7 The original image and Figure 6 The optimized reconstructed image is the image restored from the unprocessed detection value under the interference of ambient light ( Figure 7 ) is greatly disturbed and cannot present real image information. After being processed by the single-pixel imaging method for resisting ambient light interference proposed in the embodiment of the present invention, the reconstructed image ( Figure 6 ) successfully restores the real information of the object, with a strong sense of outline and outstanding overall effect. This shows that this method can effectively resist the interference of ambient light, obtain effective reconstructed images, and has practical application value.

[0081] Embodiment 2

[0082] This embodiment discloses a single-pixel image reconstruction system that is resistant to ambient light interference.

[0083] A single-pixel image reconstruction system that is resistant to ambient light interference, including:

[0084] The data acquisition module is configured to: acquire the original detection value of the target scene modulation signal of the single pixel imaging system;

[0085] The numerical fitting module is configured to: perform numerical fitting on the original detection value to obtain an ambient light change curve;

[0086] The mean value calculation module is configured to: calculate the mean value of all data in the original detection value to obtain the average signal strength;

[0087] The optimization removal module is configured to: design an optimization formula based on the ambient light change curve, the average signal intensity and the original detection value, remove the ambient light from the original detection value, and obtain the detection value after suppressing the ambient light;

[0088] The image reconstruction module is configured to: obtain a restored image of the target scene using an image reconstruction algorithm based on the detection value after suppressing the ambient light.

[0089] Embodiment 3

[0090] The purpose of this embodiment is to provide a computer-readable storage medium.

[0091] A computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the steps in the single-pixel image reconstruction method for resisting ambient light interference as described in Example 1 of the present disclosure.

[0092] Embodiment 4

[0093] The purpose of this embodiment is to provide an electronic device.

[0094] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor. When the processor executes the program, the steps in the single-pixel image reconstruction method for resisting ambient light interference as described in Example 1 of the present disclosure are implemented.

[0095] The steps involved in the apparatuses of the above embodiments 2, 3 and 4 correspond to the method embodiment 1, and the specific implementation methods can refer to the relevant description part of embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood to include any medium that can store, encode or carry an instruction set for execution by a processor and enable the processor to execute any method in the present invention.

[0096] Those skilled in the art should understand that the modules or steps of the present invention described above can be implemented by a general-purpose computer device, or alternatively, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0097] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A single-pixel image reconstruction method resistant to ambient light interference, characterized in that: The following steps are involved: Obtaining the original detection value of the target scene modulation signal of the single-pixel imaging system; Perform numerical fitting on the original detection value to obtain the ambient light change curve; Calculate the mean of all data in the original detection value to obtain the average signal strength; Based on the ambient light change curve, the average signal intensity and the original detection value, an optimization formula is designed to remove the ambient light from the original detection value to obtain the detection value after suppressing the ambient light; Based on the detection value after suppressing the ambient light, an image reconstruction algorithm is used to obtain the restored image of the target scene.

2. The single-pixel image reconstruction method against ambient light interference according to claim 1, characterized in that: Obtain the original detection value of the target scene modulation signal of the single-pixel imaging system, including: Using a single-pixel imaging system, single-pixel imaging of the target scene is performed under light interference conditions; The single-pixel imaging includes active imaging and passive imaging, and the modulation device of the single-pixel imaging system includes but is not limited to DMD, SLM, and mask.

3. The single-pixel image reconstruction method against ambient light interference according to claim 1, characterized in that: Methods for numerically fitting the original detection values ​​include, but are not limited to, Gaussian fitting, polynomial fitting, and nonlinear least squares fitting.

4. The single-pixel image reconstruction method against ambient light interference according to claim 1, characterized in that: The optimization formula is specifically: Among them, Y is the original detection value; Y1 is the ambient light change curve; is the average signal intensity; U2 is the detection value after suppressing ambient light.

5. The single-pixel image reconstruction method against ambient light interference according to claim 1, characterized in that: The image reconstruction algorithm includes but is not limited to a compressed sensing algorithm, a differential ghost imaging method and a neural network algorithm.

6. The single-pixel image reconstruction method against ambient light interference according to claim 1, characterized in that: Also includes: Generate a measurement matrix based on the resolution and sampling compression ratio; The measurement matrix is ​​loaded into the single-pixel imaging system, and the original detection value is obtained after completing a round of encoding.

7. The single-pixel image reconstruction method against ambient light interference according to claim 6, characterized in that: Also includes: The measurement matrix and the detection value after suppressing ambient light are input into the image reconstruction algorithm to complete the calculation and obtain the restored image of the target scene.

8. A single-pixel image reconstruction system resistant to ambient light interference, characterized in that: include: The data acquisition module is configured to: acquire the original detection value of the target scene modulation signal of the single pixel imaging system; The numerical fitting module is configured to: perform numerical fitting on the original detection value to obtain an ambient light change curve; The mean value calculation module is configured to: calculate the mean value of all data in the original detection value to obtain the average signal strength; The optimization removal module is configured to: design an optimization formula based on the ambient light change curve, the average signal intensity and the original detection value, remove the ambient light from the original detection value, and obtain the detection value after suppressing the ambient light; The image reconstruction module is configured to: obtain a restored image of the target scene using an image reconstruction algorithm based on the detection value after suppressing the ambient light.

9. A computer-readable storage medium having a program stored thereon, characterized in that: When the program is executed by a processor, the steps in the single-pixel image reconstruction method against ambient light interference as described in any one of claims 1 to 7 are implemented.

10. An electronic device comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps in the single-pixel image reconstruction method against ambient light interference as described in any one of claims 1 to 7 are implemented.

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