Speckle zoom compensation calculation ghost imaging method and system suitable for composite motion target

Abstract

The invention discloses a speckle zoom compensation calculation ghost imaging method and system suitable for a composite motion target, and the method comprises the following steps: determining the motion parameters and scene information of a target object in an initial state, the motion parameters and the scene information comprise the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object and the included angle between the motion track of the target object and the x axis; according to the motion parameters and the scene information of the moving target object, amplifying Hadamard speckles which are generated in advance and sequenced by walsh to obtain speckles after amplification compensation; moving and amplifying the compensated speckle to obtain a moved and amplified speckle, and storing the moved and amplified speckle to obtain a zoom compensated speckle; projecting the speckles after zooming compensation to a moving target object, and receiving a light intensity value of the moving target object by using a single-pixel detector; and carrying out correlation operation on the light intensity value and the speckle information to obtain a reconstructed image of the composite moving target.

Description

Technical Field

[0001] The present invention belongs to the technical field of optoelectronic imaging, and particularly relates to a speckle zoom compensation computational ghost imaging method and system applicable to composite moving targets. Background Art

[0002] Computational ghost imaging is a new imaging technology that uses a single-pixel optoelectronic detector without spatial resolution ability to reconstruct the image of an object. The core of this technology lies in obtaining the correlation information between the calculated light intensities, thereby restoring the spatial information of the object to be measured. Compared with traditional imaging technologies, its optical path is simpler, it can also image in non-visible light and weak light, and it is robust to light scattering. Computational ghost imaging has been widely applied in fields such as 3D imaging, terahertz imaging, X-ray imaging, multispectral imaging, scattering medium imaging, and lidar.

[0003] Currently, most of the research on computational ghost imaging technology focuses on imaging static objects. However, in real-world application scenarios, it is often necessary to capture images of dynamic targets. Since the position of a dynamic target changes continuously during the imaging process, this relative motion often leads to a decrease in imaging quality and thus affects the clarity of the image. Therefore, it is particularly crucial to improve the ghost imaging reconstruction effect for dynamic targets, which has also become one of the challenges that must be solved to promote the advancement of ghost imaging technology towards practical applications.

[0004] Computational ghost imaging technology relies on numerous samplings or measurements to reconstruct the target image. Therefore, for a stationary object, it is relatively simple to achieve high-definition image reconstruction. However, the movement of the target will result in data collected within a single sampling or a single motion frame, thereby causing the image to become blurred or even unable to complete imaging. If the motion of the target and the speckle pattern involved in the encoding during the sampling process always maintain a relatively stationary state, then theoretically, high-quality reconstruction of this moving target can also be achieved. Summary of the Invention

[0005] The present invention aims to solve the deficiencies of the prior art and provides the following solutions:

[0006] A speckle zoom compensation computational ghost imaging method applicable to composite moving targets, comprising the following steps:

[0007] Determine the motion parameters and scene information of the target object in the initial state, where the motion parameters and scene information include: the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object, and the angle between the motion trajectory of the target object and the x-axis;

[0008] According to the motion parameters and scene information of the moving target object, amplify the pre-generated Walsh-ordered Hadamard speckles to obtain amplified compensation speckles;

[0009] Move the magnified and compensated speckle to obtain the magnified speckle after movement and store it to obtain the speckle after zoom compensation;

[0010] Project the speckle after zoom compensation onto the moving target object, and use a single-pixel detector to receive the light intensity value of the moving target object;

[0011] Perform a correlation operation on the light intensity value and the speckle information to obtain a reconstructed image of the composite moving target.

[0012] Preferably, the light intensity value includes: the light intensity value in the stationary state, the light intensity value without zoom compensation, and the light intensity value with zoom compensation;

[0013] The light intensity value in the stationary state is:

[0014]

[0015] The light intensity value without zoom compensation is:

[0016]

[0017] The light intensity value with zoom compensation is:

[0018]

[0019] where M n (x, y) represents the speckle information, N(x, y) represents the information of the moving target, Δx represents the moving distance of the target object along the x-axis, and n represents that the target object is magnified by n times along the y-axis.

[0020] Preferably, the method for obtaining the reconstructed image of the composite moving target includes:

[0021] O(nx + Δx, ny) = <I″ n M n (nx + Δx, ny)> - <I″n><M n (x + Δx, y)〉

[0022] = O(x, y)

[0023] where O(x, y) represents the reconstructed image of the target object in the stationary state, and O(nx + Δx, ny) represents the reconstructed image of the target object during composite movement.

[0024] The present invention also provides a speckle zoom compensation computational ghost imaging system applicable to a composite moving target. The system applies the method described in any one of the above, and includes: a data acquisition module, a speckle magnification compensation module, a speckle movement compensation module, a light intensity acquisition module, and an image reconstruction module;

[0025] The data acquisition module is used to determine the motion parameters and scene information of the target object in the initial state. The motion parameters and scene information include: the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object, and the angle between the motion trajectory of the target object and the x-axis;

[0026] The speckle amplification compensation module amplifies the pre-generated Walsh-ordered Hadamard speckles according to the motion parameters and scene information of the moving target object to obtain amplified and compensated speckles;

[0027] The speckle movement compensation module is used to move the amplified and compensated speckles to obtain the moved and amplified speckles and store them to obtain the zoom-compensated speckles;

[0028] The light intensity acquisition module is used to project the zoom-compensated speckles onto the moving target object and use a single-pixel detector to receive the light intensity value of the moving target object;

[0029] The image reconstruction module is used to perform an associative operation on the light intensity value and the speckle information to obtain a reconstructed image of the composite moving target.

[0030] Preferably, the light intensity value includes: the light intensity value in the static state, the light intensity value without zoom compensation, and the light intensity value with zoom compensation;

[0031] The light intensity value in the static state is:

[0032]

[0033] The light intensity value without zoom compensation is:

[0034]

[0035] The light intensity value with zoom compensation is:

[0036]

[0037] where M n (x,y) represents the speckle information, N(x,y) represents the information of the moving target, Δx represents the moving distance of the target object along the x-axis, and n represents that the target object is magnified by n times along the y-axis.

[0038] Preferably, the working process of the image reconstruction module includes:

[0039] O(nx + Δx, ny) = <I″ n M n (nx + Δx, ny)> - <I″ n >> <M n (x + Δx, y)>

[0040] = O(x, y)

[0041] Among them, O(x, y) represents the reconstructed image of the target object in the static state, and O(nx + Δx, ny) represents the reconstructed image of the target object during compound motion.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0043] A speckle zoom compensation computational ghost imaging method applicable to compound motion targets disclosed by the present invention can solve the problem of image blurring caused by the relative movement between the target object and the system by adjusting the size and position of the projected speckles so that the moving object and the speckles always remain in a relatively static state. Through the speckle zoom compensation method, the correlation lost due to the relative motion between the object and the imaging system can be restored, and a high-quality reconstructed image can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts.

[0045] Figure 1 It is a schematic flowchart of the method according to an embodiment of the present invention;

[0046] Figure 2 It is a schematic diagram of the speckle zoom compensation principle according to an embodiment of the present invention;

[0047] Figure 3 It is a schematic diagram of the reconstructed image when the target is stationary and the reconstructed image when the target is moving according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0049] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0050] Embodiment 1

[0051] In this embodiment, as Figure 1As shown, a speckle zoom compensation computational ghost imaging method applicable to compound moving targets includes the following steps:

[0052] S1. Determine the motion parameters and scene information of the target object in the initial state. The motion parameters and scene information include: the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object, and the angle between the motion trajectory of the target object and the x-axis.

[0053] In this embodiment, the initial state is the state where the target object is stationary, that is, the state before the target object starts to move. Given the motion speed v and the angle α with the x-axis of the target object, let the object move on a one-dimensional guide rail. Among them, x always remains parallel to the horizontal line. Then, the speed of its component motion on the x-axis can be obtained as vcosα, and the speed of its component motion on the y-axis is vsinα. Then, for the component on the x-axis, when the object moves from time t1 to time t2, the distance the object moves is vcosα(t2 - t1). Correspondingly, in step S3, the speckle is also moved along the x-axis in the same direction (the forward direction of the component motion of the object on the x-axis) by vcosα(t2 - t1). For the convenience of calculation, it is denoted as △x hereafter; for the component on the y-axis, assume that the side length of the object in the initial state is m. When the object moves from time t1 to time t2, the side length of the object becomes m + vsinα(t2 - t1). For the convenience of calculation, it is denoted as the object being magnified by n times hereafter. Correspondingly, in step S2, the position of the center point of the speckle is kept unchanged, and the speckle is magnified so that its side length increases by vsinα(t2 - t1).

[0054] S2. According to the motion parameters and scene information of the moving target object, magnify the pre-generated Walsh-ordered Hadamard speckle to obtain the magnified and compensated speckle.

[0055] In this embodiment, the speckle is magnified to ensure that the component of the target on the y-axis always occupies the same area of the speckle. Specifically, the target object performs compound motion, that is, the target object has motion components on both the x-axis and the y-axis. In other words, the component motion of the target object on the y-axis can be equivalently considered as the position of the target object remaining unchanged while its size is gradually magnified. According to the magnification factor n of the target object obtained in step S1, the speckle is correspondingly magnified by n times to obtain the magnified and compensated speckle.

[0056] S3. Move the magnified and compensated speckle to obtain the moved and magnified speckle and store it to obtain the zoom-compensated speckle.

[0057] In this embodiment, the speckles after magnification compensation on the x-axis are ensured to keep the components of the speckles and the target on the x-axis relatively stationary all the time. Specifically, the translational motion of the target object on the x-axis can be equivalently considered as that the size of the target object remains unchanged and it makes a translational motion along the x-axis. According to the translational distance Δx of the target object obtained in step S1, the magnified and compensated speckles are also moved by Δx accordingly to obtain the speckles after zoom compensation.

[0058] S4. Project the speckles after zoom compensation onto the moving target object, and use a single-pixel detector to receive the light intensity values of the moving target object.

[0059] In this embodiment, the detector used is a single-pixel detector. The light intensity values include: light intensity values in the stationary state, light intensity values without zoom compensation, and light intensity values with zoom compensation.

[0060] When the target object is in the stationary state, the detector receives n light intensity values, that is, the light intensity values in the stationary state:

[0061]

[0062] where M n (x, y) represents the speckle information, N(x, y) represents the information of the moving target, and the range of n is the power of 2 of k, and k is greater than or equal to 32.

[0063] When the target object moves by Δx along the x-axis and is magnified by n times along the y-axis, when no speckle zoom compensation is performed, the light intensity values received by the detector are the light intensity values without zoom compensation:

[0064]

[0065] There is an obvious relative motion between the object and the speckles, and the correlation between the object light field and the speckle light field is lost, and motion blur will occur in the reconstructed image.

[0066] When speckle zoom compensation is performed on the object, the corresponding detection value is the light intensity value with zoom compensation:

[0067]

[0068] where Δx represents the moving distance of the target object along the x-axis, and n represents that the target object is magnified by n times along the y-axis. After performing speckle zoom compensation, the object and the speckles remain in a relatively stationary state, the correlation between the object light field and the speckle light field is restored, and the motion blur phenomenon in the reconstructed image is improved.

[0069] S5. Perform a correlation operation on the light intensity values and the speckle information to obtain the reconstructed image of the composite moving target.

[0070] The method for obtaining the reconstructed image of the composite moving target includes:

[0071] O(nx + Δx, ny) = <I″ n M n (nx + Δx, ny) > -<I″ n > > M n (x + Δx, y) >

[0072] = O(x, y)

[0073] Among them, O(x, y) represents the reconstructed image of the target object in a static state, and O(nx + Δx, ny) represents the reconstructed image of the target object during compound motion. Through the speckle zoom compensation method, the quality of the reconstructed image of the target object undergoing compound motion can be improved, and the motion blur phenomenon can be alleviated. The correlation operations include, but are not limited to: second-order correlation operation, TVAL3 reconstruction algorithm, etc.

[0074] Embodiment 2

[0075] In this embodiment, a speckle zoom compensation computational ghost imaging system applicable to a compound motion target includes: a data acquisition module, a speckle magnification compensation module, a speckle movement compensation module, an optical intensity acquisition module, and an image reconstruction module.

[0076] The data acquisition module is used to determine the motion parameters and scene information of the target object in the initial state. The motion parameters and scene information include: the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object, and the angle between the motion trajectory of the target object and the x-axis.

[0077] In this embodiment, the initial state is the state where the target object is at rest, that is, the state before the target object starts to move. Given the motion speed v and the angle α with the x-axis of the target object, let the object move on a one-dimensional guide rail. Among them, x always remains parallel to the horizontal line. Then, the speed of its component motion on the x-axis can be obtained as vcosα, and the speed of its component motion on the y-axis is vsinα. Then, for the component on the x-axis, when the object moves from time t1 to time t2, the distance the object moves is vcosα(t2 - t1). Correspondingly, in step S3, the speckle is also moved along the x-axis in the same direction (the forward direction of the component motion of the object on the x-axis) by vcosα(t2 - t1). For the sake of easy calculation, it is denoted as △x hereafter; for the component on the y-axis, assuming that the side length of the object in the initial state is m, and the object moves from time t1 to time t2, the side length of the object becomes m + vsinα(t2 - t1). For the sake of easy calculation, it is denoted as the object being magnified by n times hereafter. Correspondingly, in step S2, the position of the center point of the speckle remains unchanged, and the speckle is magnified so that its side length increases by vsinα(t2 - t1).

[0078] The speckle amplification compensation module amplifies the pre-generated Walsh-ordered Hadamard speckles according to the motion parameters and scene information of the moving target object to obtain the amplified and compensated speckles.

[0079] In this embodiment, the speckles are amplified to ensure that the component of the target on the y-axis always occupies the same area of the speckles. Specifically, the target object performs a composite motion, that is, the target object has motion components on both the x-axis and the y-axis. In other words, the sub-motion of the target object on the y-axis can be equivalent to that the position of the target object remains unchanged and the size is gradually amplified. According to the amplification factor n of the target object obtained in step S1, the corresponding speckles are also amplified by n times to obtain the amplified and compensated speckles.

[0080] The speckle movement compensation module is used to move the amplified and compensated speckles to obtain the moved and amplified speckles and store them to obtain the speckles after zoom compensation.

[0081] In this embodiment, the speckles amplified and compensated on the x-axis are ensured to keep the component of the speckles and the target on the x-axis always relatively stationary. Specifically, the sub-motion of the target object on the x-axis can be equivalent to that the size of the target object remains unchanged and it performs a translational motion along the x-axis. According to the translational distance △x of the target object obtained in step S1, the amplified and compensated speckles are also moved by △x accordingly to obtain the speckles after zoom compensation.

[0082] The light intensity acquisition module is used to project the speckles after zoom compensation onto the moving target object and use a single-pixel detector to receive the light intensity value of the moving target object.

[0083] In this embodiment, the detector used is a single-pixel detector. The light intensity values include: the light intensity value in the stationary state, the light intensity value without zoom compensation, and the light intensity value after zoom compensation.

[0084] When the target object is in the stationary state, the detector receives n light intensity values, that is, the light intensity values in the stationary state:

[0085]

[0086] Among them, M n (x, y) represents the speckle information, N(x, y) represents the information of the moving target, and the range of n is the power of 2 of k, and k is greater than or equal to 32.

[0087] When the target object moves △x along the x-axis and is amplified by n times along the y-axis, when the speckle zoom compensation is not performed, the light intensity value received by the detector is the light intensity value without zoom compensation:

[0088]

[0089] There is an obvious relative motion between the object and the speckle, the correlation between the object light field and the speckle light field is lost, and motion blur will occur in the reconstructed image.

[0090] When performing speckle zoom compensation on the object, the corresponding detection value is the zoom compensation light intensity value:

[0091]

[0092] Among them, Δx represents the moving distance of the target object along the x-axis, and n represents that the target object is magnified by n times along the y-axis. After performing speckle zoom compensation, the object and the speckle remain relatively stationary, the correlation between the object light field and the speckle light field is restored, and the motion blur phenomenon of the reconstructed image is improved.

[0093] The image reconstruction module is used to perform correlation operations on the light intensity value and the speckle information to obtain the reconstructed image of the composite moving target.

[0094] The working process of the image reconstruction module includes:

[0095] O(nx + Δx, ny) = <I″ n M n (nx + Δx, ny)> - <I″ n >> <M n (x + Δx, y)>

[0096] = O(x, y)

[0097] Among them, O(x, y) represents the reconstructed image of the target object in a stationary state, and O(nx + Δx, ny) represents the reconstructed image of the target object during compound motion. Through the speckle zoom compensation method, the quality of the reconstructed image of the target object performing compound motion can be improved, and the motion blur phenomenon can be improved. The correlation operations include but are not limited to: second-order correlation operations, TVAL3 reconstruction algorithms, etc.

[0098] Example Three

[0099] In this example, as Figure 2As shown, the correspondence between the object and the speckles is represented by solid and dashed boxes respectively. When the object is stationary, its position in the environment is fixed at point A, and the corresponding speckles also always remain at point A. At this time, the target object and the imaging system are relatively stationary, and there will be no motion blur phenomenon, and the imaging effect is clear. However, when the object moves from point A to point B, the position of the speckles does not change accordingly and still remains at point A. Since the system cannot provide a sufficient number of measurements, the speckles in area B can accurately modulate the light of the target object, resulting in a significant decrease in the quality of the reconstructed image and the appearance of a motion blur problem. In response to this situation, the present invention performs corresponding movement and magnification processing on the speckles according to the component motions of the object along the x-axis and y-axis. In this way, no matter where the object moves to, the speckle area used for light modulation can always move synchronously with the object, and the two are relatively stationary. In this way, the light intensity value detected by the single-pixel detector is equal to the light intensity value when the target object is stationary, effectively eliminating the motion blur problem caused by the relative motion between the target object and the imaging system. The reconstructed image is as shown in Figure 3 shown.

[0100] The embodiments described above are only descriptions of the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A speckle zoom compensation computational ghost imaging method applicable to composite moving targets, characterized in that, Including the following steps: Determine the motion parameters and scene information of the target object in the initial state. The motion parameters and scene information include: the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object, and the angle between the motion trajectory of the target object and the x-axis; According to the motion parameters and scene information of the moving target object, amplify the pre-generated Walsh-ordered Hadamard speckle to obtain an amplified and compensated speckle; Move the amplified and compensated speckle to obtain a moved and amplified speckle and store it to obtain a zoom-compensated speckle; Project the zoom-compensated speckle onto the moving target object, and use a single-pixel detector to receive the light intensity value of the moving target object; Perform an associative operation on the light intensity value and the speckle information to obtain a reconstructed image of the composite moving target.

2. The speckle zoom compensation calculation ghost imaging method for a compound moving target according to claim 1, characterized in that, The light intensity value includes: the light intensity value in the stationary state, the light intensity value without zoom compensation, and the light intensity value with zoom compensation; The light intensity value in the stationary state is: The light intensity value without zoom compensation is: The light intensity value with zoom compensation is: Among them, M n (x, y) represents the speckle information, N(x, y) represents the information of the moving target, Δx represents the moving distance of the target object along the x-axis, and n represents that the target object is magnified by n times along the y-axis.

3. The speckle zoom compensation calculation ghost imaging method for a composite moving target according to claim 2, characterized in that, The method for obtaining a reconstructed image of the composite moving target includes: O(nx + Δx, ny) = <I″ n M n (nx + Δx, ny)> - <I″ n >> M n (x + Δx, y)> = O(x,y) where O(x,y) represents the reconstructed image of the target object in the stationary state, and O(nx + Δx, ny) represents the reconstructed image of the target object during composite motion.

4. A speckle zoom compensation computational ghost imaging system applicable to compound moving targets, the system applying the method according to any one of claims 1-3, characterized in that, Including: A data acquisition module, a speckle amplification and compensation module, a speckle movement compensation module, a light intensity acquisition module, and an image reconstruction module; The data acquisition module is used to determine the motion parameters and scene information of the target object in the initial state. The motion parameters and scene information include: the size of the target object, the distance between the target object and the optical projection system, the motion speed of the target object, and the angle between the motion trajectory of the target object and the x-axis; The speckle amplification and compensation module amplifies the pre-generated Walsh-ordered Hadamard speckle according to the motion parameters and scene information of the moving target object to obtain an amplified and compensated speckle; The speckle movement compensation module is used to move the amplified and compensated speckle to obtain a moved and amplified speckle and store it to obtain a zoom-compensated speckle; The light intensity acquisition module is used to project the zoom-compensated speckle onto the moving target object and use a single-pixel detector to receive the light intensity value of the moving target object; The image reconstruction module is used to perform an associative operation on the light intensity value and the speckle information to obtain a reconstructed image of the composite moving target.

5. The speckle zoom compensation computational ghost imaging system applicable to compound moving targets according to claim 4, wherein The light intensity value includes: the light intensity value in the stationary state, the light intensity value without zoom compensation, and the light intensity value with zoom compensation; The light intensity value in the stationary state is: The light intensity value without zoom compensation is: The light intensity value with zoom compensation is: Among them, M n (x, y) represents the speckle information, N(x, y) represents the information of the moving target, Δx represents the moving distance of the target object along the x-axis, and n represents that the target object is magnified by n times along the y-axis.

6. The speckle zoom compensation computational ghost imaging system applicable to compound moving targets according to claim 5, wherein The working process of the image reconstruction module includes: O(nx + Δx, ny) = <I″ n M n (nx + Δx, ny) > -<I″ n > <M n (x + Δx, y) 〉 = O(x,y) where O(x,y) represents the reconstructed image of the target object in the stationary state, and O(nx + Δx, ny) represents the reconstructed image of the target object during composite motion.

Images