Method, device and equipment for suppressing water surface saturation glare based on polarization characteristics

Abstract

The present application relates to a method, device and computer equipment for suppressing saturated glare on a water surface based on polarization characteristics. The method includes: utilizing the water surface reflection polarization degree, refraction polarization degree, vertical direction light intensity image and parallel direction light intensity image to achieve separation and suppression of water surface glare. In view of the saturation distortion problem of the vertical direction light intensity image in the process of saturated glare separation, it is proposed to effectively restore the image information missing in the vertical direction light intensity image due to glare saturation by decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the completely polarized light intensity. The method of the present invention can effectively solve the saturation distortion problem of the vertical direction light intensity image in the process of saturated glare suppression, and suppress the saturated glare by using the restored vertical direction light intensity image, which can significantly improve the contrast and signal-to-noise ratio indicators between the target and the background in the glare area.

Description

Technical Field

[0001] The present application relates to the field of image processing technology, and in particular to a method, device and computer equipment for suppressing water surface saturation glare based on polarization characteristics. Background Art

[0002] Water surface glare refers to the strong light signal formed by the water surface directly reflecting solar radiation, cloud radiation, atmospheric radiation, etc. Water surface glare is a common natural phenomenon, but for photoelectric detection, it is a very strong interference source.

[0003] According to the intensity of the glare reflected from the water surface, the glare can be divided into two categories: unsaturated glare and saturated glare. Unsaturated glare refers to glare whose light intensity value received by the detector has not reached the saturation state. In this case, the glare intensity value obtained by the detector is within its imaging capability range, and this value will be displayed normally in the optical image without image saturation. Therefore, the light intensity image obtained by the polarization detector can be directly used to solve the polarization information. Saturated glare refers to glare whose light intensity value received by the detector has reached the saturation state. When the image obtained by the polarization detector is saturated, it will not only lead to the loss of image texture and details, but also cause distortion of polarization information, resulting in large deviations in the solution of polarization information, affecting the separation and suppression of glare. According to the polarization characteristics of the reflected light, the intensity value of the water surface reflected light is the largest in the direction of polarization perpendicular to the incident surface. Therefore, the water surface glare image obtained in the vertical direction is most likely to reach the saturation state. Existing technologies include water surface glare suppression algorithms based on image features such as image fusion, image restoration, and image filtering, but the suppression effect is poor. Alternatively, glare is suppressed by using a polarizing film method, but there are problems such as target energy loss and water-leaving radiation loss in the process. Therefore, the existing technologies have the problem of poor adaptability. Summary of the invention

[0004] Based on this, it is necessary to provide a method, device, computer equipment and storage medium for suppressing water surface saturated glare based on polarization characteristics, which can better achieve water surface glare separation and suppression, in order to address the above technical problems.

[0005] A method for suppressing water surface saturation glare based on polarization characteristics, the method comprising:

[0006] Acquire a parallel direction light intensity image of the water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector;

[0007] By decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the completely polarized light intensity, a vertical direction light intensity image is obtained by a preset formula according to the parallel direction light intensity image and the unsaturated light intensity image;

[0008] The water surface reflection polarization degree and the water surface refraction polarization degree are obtained, and the parallel direction light intensity image and the vertical direction light intensity image are separated into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression.

[0009] In one of the embodiments, it also includes: obtaining a parallel direction light intensity image of the water surface scene to be processed at a starting angle of 90° through a horizontally placed 0°, 45°, 90°, and 135° four-channel focal plane polarization detector, and obtaining a corresponding non-saturated light intensity image at a starting angle of 45° or 135°.

[0010] In one embodiment, the method further includes: decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the fully polarized light intensity, and obtaining the vertical direction light intensity image by a preset formula according to the parallel direction light intensity image and the unsaturated light intensity image; the preset formula is:

[0011]

[0012] in, is the vertical light intensity image, is the parallel direction light intensity image, is the non-saturated light intensity image corresponding to the polarization direction α1.

[0013] In one of the embodiments, it further includes: calculating the water surface observation angle by measuring the pitch angle of the polarization detector;

[0014] The water surface reflection polarization degree and the water surface refraction polarization degree are calculated according to the water surface observation angle.

[0015] In one of the embodiments, the method further includes: separating the parallel direction light intensity image and the vertical direction light intensity image into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; wherein the refracted light image is:

[0016]

[0017] Among them, (i, j) represents the coordinate position of the pixel point, I T (i, j) is the refracted light image, γ(i, j) is the reflected polarization degree, χ(i, j) is the refracted polarization degree, I || (i, j) is the parallel direction light intensity image, I ⊥ (i, j) is the vertical light intensity image.

[0018] In one of the embodiments, the method further includes: after obtaining the saturated flare suppressed image, evaluating the saturated flare suppression effect by calculating the contrast and signal-to-noise ratio between the target and the background before and after the flare suppression.

[0019] A device for suppressing water surface saturation glare based on polarization characteristics, the device comprising:

[0020] An image acquisition module, used for acquiring a parallel direction light intensity image of a water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector;

[0021] A vertical direction light intensity image restoration module is used to decompose the vertical direction light intensity into the sum of the parallel direction light intensity and the fully polarized light intensity, and obtain the vertical direction light intensity image according to a preset formula based on the parallel direction light intensity image and the unsaturated light intensity image;

[0022] The saturated glare separation and suppression module is used to obtain the water surface reflection polarization degree and the water surface refraction polarization degree, and separate the parallel direction light intensity image and the vertical direction light intensity image into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression.

[0023] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0024] Acquire a parallel direction light intensity image of the water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector;

[0025] By decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the completely polarized light intensity, a vertical direction light intensity image is obtained by a preset formula according to the parallel direction light intensity image and the unsaturated light intensity image;

[0026] The water surface reflection polarization degree and the water surface refraction polarization degree are obtained, and the parallel direction light intensity image and the vertical direction light intensity image are separated into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression.

[0027] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:

[0028] Acquire a parallel direction light intensity image of the water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector;

[0029] By decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the completely polarized light intensity, a vertical direction light intensity image is obtained by a preset formula according to the parallel direction light intensity image and the unsaturated light intensity image;

[0030] The water surface reflection polarization degree and the water surface refraction polarization degree are obtained, and the parallel direction light intensity image and the vertical direction light intensity image are separated into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression.

[0031] The above-mentioned method, device and computer equipment for suppressing saturated glare on the water surface based on polarization characteristics realize the separation and suppression of water surface glare by utilizing the water surface reflection polarization degree, refraction polarization degree, vertical direction light intensity value and parallel direction light intensity value, and propose a vertical direction saturated light intensity image restoration method based on complete polarization decomposition to address the problem of poor glare separation effect caused by saturation distortion of vertical direction light intensity image, which effectively restores the image information missing due to glare saturation in the vertical direction light intensity image by decomposing the vertical direction light intensity into the sum of parallel direction light intensity and complete polarization light intensity. The present invention suppresses saturated glare by using the restored vertical direction light intensity image and parallel direction light intensity image, which can eliminate image noise caused by pixel saturation in the glare area, and the glare component formed by water surface reflection is separated cleanly, and the contrast and signal-to-noise ratio indicators between the target and the background in the glare area are significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic flow chart of a method for suppressing water surface saturation glare based on polarization characteristics in one embodiment;

[0033] Figure 2 It is a schematic diagram of a flow chart of a method for suppressing water surface saturation glare based on polarization characteristics in a specific embodiment;

[0034] Figure 3 1 is a vertical light intensity image of three scenes in a specific embodiment, wherein (a) is a vertical light intensity image of scene one, (b) is a vertical light intensity image of scene two, and (c) is a vertical light intensity image of scene three;

[0035] Figure 4 The flare suppression results of the vertical light intensity images of three scenes in a specific embodiment are shown in FIG. 1 , where (a) is the flare suppression result of the vertical light intensity image of scene 1 under the saturated state, (b) is the flare suppression result of the vertical light intensity image of scene 2 under the saturated state, and (c) is the flare suppression result of the vertical light intensity image of scene 3 under the saturated state;

[0036] Figure 5Figures 2 and 3 are flare suppression results after saturation restoration of vertical light intensity images of three scenes in a specific embodiment, wherein (a) is the flare suppression result after saturation restoration of vertical light intensity images of scene one, (b) is the flare suppression result after saturation restoration of vertical light intensity images of scene two, and (c) is the flare suppression result after saturation restoration of vertical light intensity images of scene three;

[0037] Figure 6 is a structural block diagram of a water surface saturation glare suppression device based on polarization characteristics in one embodiment;

[0038] Figure 7 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0040] In one embodiment, Figure 1 As shown, a method for suppressing water surface saturation glare based on polarization characteristics is provided, comprising the following steps:

[0041] Step 102, obtaining a parallel direction light intensity image of the water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector.

[0042] Since the light waves reflected from the water surface have obvious polarization characteristics, the analysis and research of the polarization characteristics of the light reflected from the water surface can provide a theoretical basis and technical support for the separation and suppression of water surface glare. The light intensity of the water surface received by the detector mainly includes the following two parts: one part is the light waves directly reflected from the water surface, which we call the water surface reflected light, and the water surface reflected light is the main source of glare; the other part is the light waves emitted upward after being scattered or reflected by the particles inside the water body and then refracted by the water surface, which we call the water surface refracted light. The ultimate goal of water surface glare suppression is to separate the water surface reflected glare and obtain the water surface refracted light.

[0043] The main difficulty in the saturated flare separation process is that the vertical intensity image obtained by the polarization detector is severely distorted. Since the intensity of the glare reflected from the water surface is mainly distributed in the vertical direction, the intensity image obtained by the polarization detector with the polarization direction near the vertical direction will reach the saturation value.

[0044] In view of the problem of saturation distortion of the vertical light intensity image acquired by the polarization detector, the present invention proposes a vertical light intensity image restoration method based on complete polarization decomposition. The vertical light intensity is decomposed into the sum of the parallel light intensity and the complete polarization light intensity, and then the non-saturated polarization image is acquired by the focal plane detector. The image information lost in the vertical light intensity image due to glare saturation can be effectively restored.

[0045] Specifically, according to the principle of complete polarization decomposition, polarized light can be decomposed into natural light and completely polarized light:

[0046]

[0047] Where α represents the deflection angle, I α It indicates the polarized light intensity value corresponding to the polarization angle α. It indicates the natural light intensity value corresponding to the deflection angle of α. It represents the intensity value of completely polarized light when the polarization angle is α, I N Indicates the intensity of natural light in polarized light, I P It represents the intensity value of completely polarized light in polarized light, and A represents the polarization angle.

[0048] In the parallel direction α || =A±π / 2, the water surface glare intensity is minimum, at this time:

[0049]

[0050] where α || Indicates the angle value corresponding to the parallel direction when the deflection angle is parallel. Indicates the light intensity value in the parallel direction.

[0051] In the vertical direction α ⊥ =A±kπ, k=0, 1, the water surface glare intensity is maximum, at this time:

[0052]

[0053] where α ⊥ Indicates the angle value corresponding to the vertical direction when the deflection angle is vertical. Indicates the vertical light intensity value.

[0054] It can be seen from formula (3) that the vertical light intensity value Equal to the light intensity in the parallel direction and the intensity of completely polarized light I P This is why the vertical light intensity image obtained by the polarization detector is easily saturated. After reaching saturation, it is impossible to directly obtain effective vertical light intensity information through the polarization detector. It belongs to the non-saturated state. If the calculated value of the fully polarized light intensity I P , the vertical light intensity can be calculated by the above formula This avoids the saturation problem that occurs when the polarization detector directly acquires the vertical light intensity image.

[0055] For water surface glare, not all polarization directions have saturated light intensity values. If there is a polarization angle α1, the polarization image obtained at this angle does not reach the saturation value. Therefore, the polarization detector can be used to obtain the light intensity image at the polarization direction α1. Then use Solve for the fully polarized light intensity value I P :

[0056]

[0057] but:

[0058]

[0059] Since α1 and are all known quantities, so we can find I P :

[0060]

[0061] The vertical light intensity can be obtained by the above formula for:

[0062]

[0063] When using a polarization detector to observe water surface glare, since the direction of the water surface is fixed, the polarization angle direction is also fixed. For the convenience of calculation, let the direction perpendicular to the horizontal plane be the polarization angle reference direction. At this time, the corresponding water surface glare polarization angle A is 0°, so the above formula can be simplified to:

[0064]

[0065] Therefore, when the light intensity image in the vertical direction directly acquired using the polarization detector reaches saturation, the light intensity image in the vertical direction can be obtained by using the light intensity image in the parallel direction and the light intensity image acquired in any non-saturated polarization direction.

[0066] Step 104, by decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the completely polarized light intensity, a vertical direction light intensity image is obtained according to the parallel direction light intensity image and the unsaturated light intensity image by a preset formula.

[0067] The preset formula is derived in step 102.

[0068] Theoretically, the non-saturated polarization direction α1 can be any non-saturated polarization angle except the parallel direction. The polarization detector used in this embodiment is a four-channel focal plane polarization detector of 0°, 45°, 90°, and 135°. When the polarization detector is placed horizontally, the horizontal axis of the imaging plane coincides with the horizontal plane direction. The light intensity image acquired at a 0° polarization angle is the vertical direction light intensity image, and the light intensity image acquired at a 90° polarization angle is the parallel direction light intensity image. When the vertical direction light intensity image (0° image) acquired by the detector is in a saturated state, the vertical direction light intensity image can be obtained by using the light intensity images acquired at 90° and 45° or 90° and 135° polarization angles, thereby restoring the saturated vertical direction light intensity image.

[0069] Step 106, obtaining the water surface reflection polarization degree and the water surface refraction polarization degree, and separating the parallel direction light intensity image and the vertical direction light intensity image into the reflected light image and the refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree.

[0070] After obtaining the restored vertical light intensity image, the water surface glare suppression algorithm based on polarization reflective refraction effect can effectively separate and suppress the water surface saturated glare by using the reflected polarization degree and the refractive polarization degree. The refracted light image is the image after saturated glare suppression.

[0071] Water surface glare is caused by the strong mirror reflection effect on the water surface. The essence of water surface glare suppression is the separation of mirror reflected light on the surface of smooth objects.

[0072] Specifically, according to the principle of polarization orthogonal decomposition, the light intensity component I in the vertical direction of the water surface received by the detector is ⊥ and the parallel light intensity component I || They are:

[0073]

[0074] in, and They represent the vertical and parallel intensity components of the reflected light from the water surface, and They represent the vertical and parallel intensity components of the refracted light on the water surface, and (i, j) represents the coordinate position of the pixel point. Here, the vertical and parallel directions refer to the directions relative to the incident surface.

[0075] Since both reflected light and refracted light are polarized light, according to the definition of polarization degree, the reflected polarization degree γ and the refracted polarization degree χ can be solved by the light intensity components in the orthogonal directions as follows:

[0076]

[0077]

[0078] Substituting equations (10) and (11) into equation (9), we can obtain the intensity components of the refracted light on the water surface in the vertical and parallel directions:

[0079]

[0080] At the same time, the light intensity components of the reflected light from the water surface in the vertical and parallel directions are determined as

[0081]

[0082] The total light intensity is equal to the sum of the light intensities in the vertical and parallel directions. The water surface reflected light intensity and refracted light intensity are obtained based on the reflected polarization degree γ and the refracted polarization degree χ as follows:

[0083]

[0084] Through the above formula, the reflection polarization degree and the refraction polarization degree can be used to separate the vertical light intensity image and the parallel light intensity image obtained by the polarization detector into a reflected light image and a refracted light image. The separated reflected light image is the glare component of the mirror reflection of the water surface, and the separated refracted light image is the image after glare suppression.

[0085] It can be seen from formula (14) that the refracted light intensity on the water surface is jointly determined by the reflected polarization degree, the refracted polarization degree, the vertical direction light intensity and the parallel direction light intensity. Since the refractive index of the water body is fixed, the observation angle of the detector relative to the water surface can also be measured by an angle measuring instrument. When the observation angle and the refractive index are known, the reflected polarization degree and the refracted polarization degree can be directly obtained. Therefore, how to calculate the vertical direction light intensity of the water surface becomes the key to suppressing the saturated glare of the water surface. The present invention can solve the problem of serious distortion of the vertical direction light intensity image obtained by the polarization detector through steps 102 and 104, so that the effect of glare separation and suppression performed by step 106 is further improved.

[0086] In the above-mentioned method for suppressing saturated glare on the water surface based on polarization characteristics, the vertical light intensity is decomposed into the sum of the parallel light intensity and the fully polarized light intensity, and the vertical light intensity image is calculated and restored using the parallel light intensity image and the light intensity image obtained in any non-saturated polarizing direction. Then, the water surface reflection polarization degree and the refraction polarization degree are calculated according to the observation angle. According to the principle of orthogonal decomposition of polarization, the water surface reflection polarization degree, the refraction polarization degree, and the vertical light intensity image and the parallel light intensity image obtained by the polarization detector are used to separate and suppress the water surface glare. The method of the present invention can effectively solve the problem of saturation distortion of the vertical light intensity image in the process of suppressing saturated glare, and suppress the saturated glare by using the restored vertical light intensity image and the parallel light intensity image, which can eliminate the image noise caused by pixel saturation in the glare area, and significantly improve the contrast and signal-to-noise ratio indicators between the target and the background in the glare area.

[0087] In one of the embodiments, the method further includes: calculating a water surface observation angle by measuring the pitch angle of the polarization detector; and calculating a water surface reflection polarization degree and a water surface refraction polarization degree according to the water surface observation angle.

[0088] In a specific embodiment, Figure 2 The flowchart of water surface saturation glare suppression is shown, including: for the vertical direction saturation light intensity image, the saturation light intensity recovery algorithm based on complete polarization decomposition proposed by the present invention is used to calculate a new vertical direction light intensity image using the parallel direction light intensity image (90° image) and a light intensity image (135° image) obtained in a non-saturated polarization direction. In addition, the water surface reflection polarization degree and refraction polarization degree are calculated by the observation angle of the polarization detector, and then the reflection polarization degree and refraction polarization degree are used to solve the water surface reflection light intensity value and the refraction light intensity value, and finally the water surface glare is suppressed by separating the water surface reflection light and retaining the water surface refraction light.

[0089] Figure 3 are the vertical light intensity images of the three scenes, from Figure 3 It can be seen that due to the large intensity of the glare reflected from the water surface, there are a large number of saturated pixels in the vertical light intensity image obtained by the polarization detector. The target is completely submerged in the saturated glare, which causes distortion or even loss of polarization information, bringing great obstacles to the separation and suppression of glare.

[0090] The water surface glare suppression algorithm based on polarization reflective refraction effect is used to directly suppress the glare of the saturated light intensity image obtained by the polarization detector. The direct suppression results are as follows: Figure 4 As shown. Figure 4The area surrounded by the square box contains a large number of saturated flare pixels. There will be information distortion when solving the polarization characteristics, so the flare components of the saturated pixels in this domain cannot be completely separated. The residual flare components form noise points with higher brightness values. These noise points interfere with the detection and identification of surface targets and underwater targets.

[0091] In order to eliminate the influence of saturation distortion of vertical intensity image on glare separation results, we use the saturation intensity recovery algorithm based on complete polarization decomposition to restore the vertical intensity image, and then use the water surface glare suppression algorithm based on polarization reflection refraction effect to suppress glare. The glare suppression results are shown in Figure 2. Figure 5 As shown. Figure 5 It can be seen that in Figure 4 The noise points with higher brightness values ​​caused by pixel saturation have been effectively suppressed, indicating that the saturated light intensity recovery algorithm based on complete polarization decomposition proposed in this paper can eliminate the influence of saturation distortion on water surface glare suppression.

[0092] In order to quantitatively evaluate the enhancement effect of glare suppression on surface and underwater targets, this embodiment calculates and compares the changes in the contrast C (Contrast) and the signal-to-noise ratio LSCR (Local signal-to-noise ratio) between the target and the background before and after glare suppression, as shown in Table 1.

[0093] Contrast refers to the degree of contrast between the target and the background in the flare area. The change in contrast before and after flare removal can reflect the effect of flare suppression on the improvement of target saliency. The greater the contrast, the more obvious the improvement of target saliency after flare suppression. The signal-to-noise ratio quantifies the intensity relationship between the target signal and background noise. A negative signal-to-noise ratio indicates that the background noise is stronger than the target signal, and a positive signal-to-noise ratio indicates that the target signal is stronger than the background noise. The larger the signal-to-noise ratio, the smaller the impact of noise on the target and the stronger the target signal. The calculation formulas for contrast C and signal-to-noise ratio LSCR are as follows:

[0094]

[0095]

[0096] Among them, μ T Indicates the average target intensity, μ B represents the average local background intensity, σ B Represents the standard deviation of the local background intensity.

[0097] Table 1 Quantitative comparison of contrast and signal-to-noise ratio between target and background

[0098]

[0099] The contrast and signal-to-noise ratio are used to quantitatively evaluate the saturated glare four-channel intensity image obtained by the polarization detector and the image after glare separation, as shown in Table 1. The first to fourth rows in Table 1 respectively represent the target and background contrast and signal-to-noise ratio indicators in the 0°, 45°, 90°, and 135° four-channel intensity images obtained by the polarization detector, the fifth row represents the target and background contrast and signal-to-noise ratio indicators calculated after directly suppressing the saturated glare, and the sixth row represents the target and background contrast and signal-to-noise ratio indicators calculated after suppressing the saturated glare using the saturated intensity recovery method based on complete polarization decomposition. It can be seen from Table 1 that the contrast and signal-to-noise ratio indicators between the target and the background in the 90° intensity image are higher than those in the 0° intensity image, which verifies the conclusion that the intensity value of the glare reflected from the water surface in the vertical direction is greater than the intensity value in the parallel direction. The water surface glare suppression algorithm based on the polarization reflective refraction effect is used to directly suppress glare on the light intensity image containing saturated pixels obtained by the polarization detector. The contrast and signal-to-noise ratio between the target and the background in the image after glare suppression are improved compared with the four-channel light intensity image obtained by the polarization detector. This shows that the water surface glare suppression algorithm based on the polarization reflective refraction effect can suppress water surface glare and enhance the target. However, due to the influence of the saturation distortion of the light intensity image in the vertical direction, the improvement effect of the target contrast and signal-to-noise ratio is limited. For example, the improved signal-to-noise ratio in scenes two and three is still less than 0, indicating that the clutter caused by the glare has not been completely separated, and the target in the image is still seriously interfered by the background noise. After restoring the vertical light intensity image using the polarization complete decomposition method, the glare is suppressed using the water surface glare suppression method based on the polarization reflective refraction effect. The contrast between the target and the background in the image after glare suppression and the signal-to-noise ratio are higher than those obtained by directly separating the saturated distorted image. After glare suppression, the signal-to-noise ratios in the above three scenarios are all greater than 0, indicating that the target signal is stronger than the background clutter signal after glare suppression. This verifies the effectiveness of the saturated light intensity recovery algorithm based on complete polarization decomposition proposed in this paper in improving the saturated glare suppression results.

[0100] It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0101] In one embodiment, Figure 6 As shown, a water surface saturation glare suppression device based on polarization characteristics is provided, comprising: an image acquisition module 602, a vertical light intensity image restoration module 604 and a saturation glare separation suppression module 606, wherein:

[0102] An image acquisition module 602 is used to acquire a parallel direction light intensity image of a water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector;

[0103] A vertical direction light intensity image recovery module 604 is used to decompose the vertical direction light intensity into the sum of the parallel direction light intensity and the fully polarized light intensity, and obtain the vertical direction light intensity image according to a preset formula based on the parallel direction light intensity image and the unsaturated light intensity image;

[0104] The saturated glare separation and suppression module 606 is used to obtain the water surface reflection polarization degree and the water surface refraction polarization degree, and separate the parallel direction light intensity image and the vertical direction light intensity image into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression.

[0105] The image acquisition module 602 is also used to obtain the parallel direction light intensity image of the water surface scene to be processed at a starting angle of 90° through a horizontally placed 0°, 45°, 90°, and 135° four-channel focal plane polarization detector, and to obtain the corresponding non-saturated light intensity image at a starting angle of 45° or 135°.

[0106] The vertical direction light intensity image recovery module 604 is further used to decompose the vertical direction light intensity into the sum of the parallel direction light intensity and the fully polarized light intensity, and obtain the vertical direction light intensity image according to the parallel direction light intensity image and the unsaturated light intensity image by a preset formula; the preset formula is:

[0107]

[0108] in, is the vertical light intensity image, is the parallel direction light intensity image, is the non-saturated light intensity image corresponding to the polarization direction α1.

[0109] The saturated glare separation suppression module 606 is further used to calculate the water surface observation angle by measuring the pitch angle of the polarization detector; and calculate the water surface reflection polarization degree and the water surface refraction polarization degree according to the water surface observation angle.

[0110] The saturated glare separation and suppression module 606 is further used to separate the parallel direction light intensity image and the vertical direction light intensity image into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; wherein the refracted light image is:

[0111]

[0112] Among them, (i, j) represents the coordinate position of the pixel point, I T (i, j) is the refracted light image, γ(i, j) is the reflected polarization degree, χ(i, j) is the refracted polarization degree, I || (i, j) is the parallel direction light intensity image, I ⊥ (i, j) is the vertical light intensity image.

[0113] The saturated flare separation and suppression module 606 is further used to evaluate the saturated flare suppression effect by calculating the contrast and signal-to-noise ratio between the target and the background before and after flare suppression after obtaining the saturated flare suppressed image.

[0114] For the specific definition of the water surface saturated glare suppression device based on polarization characteristics, please refer to the definition of the water surface saturated glare suppression method based on polarization characteristics above, which will not be repeated here. Each module in the above-mentioned water surface saturated glare suppression device based on polarization characteristics can be fully or partially implemented by software, hardware and their combination. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

[0115] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 7 As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for suppressing water surface saturation glare based on polarization characteristics is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0116] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0117] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps in the above method embodiment when executing the computer program.

[0118] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiment are implemented.

[0119] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0120] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0121] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for suppressing water surface saturation glare based on polarization characteristics, characterized in that: The method comprises: Acquire a parallel direction light intensity image of the water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector; By decomposing the vertical direction light intensity into the sum of the parallel direction light intensity and the fully polarized light intensity, a vertical direction light intensity image is obtained according to the parallel direction light intensity image and the unsaturated light intensity image by a preset formula; the preset formula is: in, is the vertical light intensity image, is the light intensity image in the parallel direction, is the non-saturated light intensity image corresponding to the polarization direction α1; Obtain the water surface reflection polarization degree and the water surface refraction polarization degree, and separate the parallel direction light intensity image and the vertical direction light intensity image into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression; wherein the refracted light image is: Among them, (i, j) represents the coordinate position of the pixel point, I T (i, j) is the refracted light image, γ(i, j) is the reflected polarization degree, χ(i, j) is the refracted polarization degree, I || (i, j) is the parallel direction light intensity image, I ⊥ (i, j) is the vertical light intensity image.

2. The method according to claim 1, characterized in that The parallel direction light intensity image of the water surface scene to be processed and the unsaturated light intensity image corresponding to any unsaturated polarization direction are obtained through the polarization detector, including: Through the horizontally placed 0°, 45°, 90°, and 135° four-channel focal plane polarization detector, the parallel direction light intensity image of the water surface scene to be processed is obtained at a 90° starting angle, and the corresponding non-saturated light intensity image is obtained at a 45° or 135° starting angle.

3. The method according to claim 1, characterized in that Obtain the water surface reflection polarization degree and water surface refraction polarization degree, including: The water surface observation angle is calculated by measuring the pitch angle of the polarization detector; The water surface reflection polarization degree and the water surface refraction polarization degree are calculated according to the water surface observation angle.

4. The method according to claim 1, characterized in that The method further comprises: After obtaining the saturated flare suppression image, the saturated flare suppression effect is evaluated by calculating the contrast and signal-to-noise ratio between the target and the background before and after flare suppression.

5. A water surface saturation glare suppression device based on polarization characteristics, characterized in that: The device comprises: An image acquisition module, used for acquiring a parallel direction light intensity image of a water surface scene to be processed and an unsaturated light intensity image corresponding to any unsaturated polarization direction through a polarization detector; The vertical direction light intensity image recovery module is used to decompose the vertical direction light intensity into the sum of the parallel direction light intensity and the fully polarized light intensity, and obtain the vertical direction light intensity image according to the parallel direction light intensity image and the unsaturated light intensity image by a preset formula; the preset formula is: in, is the vertical light intensity image, is the parallel direction light intensity image, is the non-saturated light intensity image corresponding to the polarization direction α1; The saturated glare separation and suppression module is used to obtain the water surface reflection polarization degree and the water surface refraction polarization degree, and separate the parallel direction light intensity image and the vertical direction light intensity image into a reflected light image and a refracted light image according to the water surface reflection polarization degree and the water surface refraction polarization degree; the refracted light image is the image after saturated glare suppression; wherein the refracted light image is: Among them, (i, j) represents the coordinate position of the pixel point, I T (i, j) is the refracted light image, γ(i, j) is the reflected polarization degree, χ(i, j) is the refracted polarization degree, I || (i, j) is the parallel direction light intensity image, I ⊥ (i, j) is the vertical light intensity image.

6. The device according to claim 5, characterized in that The image acquisition module is also used for: Through the horizontally placed 0°, 45°, 90°, and 135° four-channel focal plane polarization detector, the parallel direction light intensity image of the water surface scene to be processed is obtained at a 90° starting angle, and the corresponding non-saturated light intensity image is obtained at a 45° or 135° starting angle.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

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