A method for identifying fast-moving targets based on anti-color feature trajectories

Abstract

The present invention provides a method for identifying fast-moving targets based on anti-color feature trajectories, including: obtaining a series of sequential observation images containing fast-moving targets and establishing an image database, where the series of sequential observation images includes multiple original observation images; respectively preprocessing the multiple original observation images; respectively performing astronomical position calibration on the preprocessed multiple original observation images; arbitrarily selecting one of the series of sequential observation images after preprocessing and astronomical position calibration as a template image, where the remaining non-template images are scientific images; based on the template image, respectively performing background subtraction on the multiple scientific images in chronological order; performing superposition and merging of the template image after background subtraction and the multiple scientific images based on the astronomical position to obtain a dynamic trajectory map; identifying the fast-moving targets based on the dynamic trajectory map. This method can achieve fast identification of targets only by constructing special anti-color feature trajectories of fast-moving targets.

Description

Technical Field

[0001] The present invention relates to the technical field of astronomical target recognition, and particularly to a method for recognizing fast-moving targets based on anti-color feature trajectories. Background Art

[0002] Space debris and near-Earth asteroids are the two major space threats currently faced by humanity. With the continuous progress of space technology and the increasing frequency of human space activities, the number of centimeter-sized space debris that poses a hazard to space activities has reached the million level, and the number of millimeter-sized space debris with potential risks exceeds 100 million. In addition, the number of events of near-Earth asteroids colliding with the Earth is increasing, posing a major potential risk to the stability of human society and the survival of life on Earth. At the stage of recognizing such fast-moving targets, it becomes difficult to distinguish between stellar, planetary, and space debris targets due to their morphological similarities. A major challenge we face is how to quickly and effectively extract fast-moving targets from background images.

[0003] Existing methods for recognizing fast-moving targets using feature trajectories mainly align a series of sequential images taken by observations according to astronomical coordinate positions and directly merge the images. Although the moving trajectories of fast-moving targets can be seen in the images by this method, the trajectories generated by this method are mixed in a large number of stellar bright sources and other interferences, making it difficult to quickly and accurately extract and recognize. These interferences are mainly composed of several aspects, such as noise, camera hardware defects, and overexposure of bright sources. Traditional trajectory recognition methods not only cannot avoid problems but may also introduce more image interferences after superposition. Summary of the Invention

[0004] (I) Technical Problems to be Solved

[0005] Aiming at the above deficiencies, the main purpose of the present invention is to provide a method for recognizing fast-moving targets based on anti-color feature trajectories, which can deduct the interferences of stellar bright sources and other backgrounds, and only needs to construct special anti-color feature trajectories of fast-moving targets to achieve fast recognition of the targets.

[0006] (II) Technical Solutions

[0007] To achieve the above object, the present invention provides a method for identifying fast-moving targets based on anti-color feature trajectories, including: obtaining a series of sequential observation images containing fast-moving targets and establishing an image database, where the series of sequential observation images includes multiple original observation images; respectively preprocessing the multiple original observation images; respectively performing astronomical position calibration on the preprocessed multiple original observation images; selecting any one of the series of sequential observation images after preprocessing and astronomical position calibration as a template image, where the remaining non-template images are scientific images; based on the template image, respectively performing background subtraction on the multiple scientific images in chronological order; performing superposition and merging of the template image after background subtraction and the multiple scientific images based on the astronomical position to obtain a dynamic trajectory map; and identifying the fast-moving target based on the dynamic trajectory map.

[0008] In the above solution, the series of sequential observation images includes at least 3 original observation images; and multiple original observation images in the series of sequential observation images are obtained at a preset observation time interval.

[0009] In the above solution, the template image is the first image obtained in the series of sequential observation images.

[0010] In the above solution, based on the template image, respectively performing background subtraction on the multiple scientific images in chronological order includes: at a preset observation time interval, performing image subtraction on both the template image and the multiple scientific images; after the subtraction is completed, respectively obtaining a first target in the template image and second targets in the multiple scientific images.

[0011] In the above solution, the first target and the second targets are displayed as anti-colors in the image.

[0012] In the above solution, performing superposition and merging of the template image after background subtraction and the multiple scientific images based on the astronomical position to obtain a dynamic trajectory map includes: searching for the feature trajectories of the second targets; constructing a dynamic trajectory map containing the first target and multiple second targets gathered together.

[0013] In the above solution, identifying the fast-moving target based on the dynamic trajectory map includes: based on the dynamic trajectory map, extracting the time and position of the fast-moving target trajectory to obtain the fast-moving target.

[0014] (III) Beneficial effects

[0015] The technical solution of the embodiment of the present invention has at least the following beneficial effects:

[0016] (1) The trajectory feature image generated by the method of using the anti-color feature trajectory to identify fast-moving targets can not only ensure the uniqueness of extracting fast-moving targets, but also construct a trajectory feature image with a purer background, almost no bright sources and other potential interferences, thus providing more accurate and stable recognition features and improving the efficiency and accuracy of recognition.

[0017] (2) The method uses the anti-color feature trajectory to quickly locate and identify these fast-moving targets, ensuring timely monitoring of fast-moving targets mainly including space debris targets and near-Earth asteroids, being able to detect critical moments in time and intervene in a timely manner to avoid losses of personnel and property.

[0018] (3) The method can batch process observation images in sequential observation images, reducing the labor cost and time cost of identifying fast-moving targets and improving the accuracy of recognition and the stability of the recognition rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematically shows a flowchart of a method for identifying fast-moving targets based on anti-color feature trajectories according to an embodiment of the present invention;

[0020] Figure 2 Shows a template image according to an embodiment of the present invention;

[0021] Figure 3 Shows a scientific image according to an embodiment of the present invention;

[0022] Figure 4 Shows an image obtained by respectively performing background subtraction on a scientific image based on a template image according to an embodiment of the present invention;

[0023] Figure 5 Shows an image obtained by superimposing to obtain a dynamic trajectory map according to an embodiment of the present invention;

[0024] Figure 6 Shows an effect diagram of an anti-color feature trajectory according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In the following detailed description, for the sake of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, obviously, one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0026] The terms used herein are merely for describing specific embodiments and are not intended to limit the present invention. The terms "comprising", "including" and the like used herein indicate the presence of features, steps, operations and / or components, but do not preclude the presence or addition of one or more other features, steps, operations or components.

[0027] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0028] Figure 1 A flowchart of a method for identifying a fast-moving target based on an anti-color feature trajectory according to an embodiment of the present invention is schematically shown.

[0029] Please refer specifically to Figure 1 , in an embodiment of the present invention, the method for identifying a fast-moving target based on an anti-color feature trajectory specifically includes steps S110 to S170.

[0030] Step S110, obtaining a series of sequential observation images including a fast-moving target and establishing an image database, where the series of sequential observation images includes multiple original observation images.

[0031] In an embodiment of the present invention, the series of sequential observation images includes at least 3 original observation images; and a plurality of original observation images in the series of sequential observation images are obtained at a preset observation time interval.

[0032] Specifically, in order to obtain the position change of the fast-moving target, there needs to be a certain time interval between the observation shooting times of the multiple original observation images constituting the database, for example, it can be in the range of several minutes to half an hour.

[0033] It should be noted that when observing and photographing the target, in order to obtain better motion trajectory features, the target is generally photographed at the same time interval, but different interval durations are also possible. In addition, in order to obtain a complete motion trajectory and more motion trajectory data points, it is necessary to ensure that the number of original observation images in the series of sequential images for observation is greater than 3.

[0034] For example, multiple FITS format images including a fast-moving target are photographed and a processing database is established. The normal background of a FITS image is gray, and the white bright sources are various celestial bodies. When photographing the observation target, the target is photographed with the same exposure duration and the same interval time, and the sequential observation images are saved for subsequent processing.

[0035] Step S120, respectively preprocessing the multiple original observation images.

[0036] In an embodiment of the present invention, preprocessing is performed on a plurality of original observation images respectively, where the preprocessing includes: correcting the background image and the flat field image for each of the plurality of original observation images; and removing cosmic rays from each of the original observation images.

[0037] Specifically, in order to exclude the interference items brought by the machine to the original observation images, preprocessing is performed on the plurality of original observation images respectively to correct the background image and the flat field image, and to remove cosmic rays and the like from each of the original observation images.

[0038] Step S130, perform astronomical position calibration on the plurality of preprocessed original observation images respectively.

[0039] In an embodiment of the present invention, performing astronomical position calibration on the plurality of preprocessed original observation images respectively includes: performing astronomical position calibration on the original observation images respectively through the WCS (World Coordinate System) to determine the specific positions on the celestial sphere to which the pixel points on the original observation images are mapped.

[0040] Specifically, performing astronomical position calibration on the plurality of preprocessed original observation images respectively is an important step in astronomical data processing, which ensures the precise alignment of the images and the accuracy of subsequent analysis.

[0041] The WCS (World Coordinate System) system is used for astronomical position calibration. It is a coordinate system for astronomical images that describes the geometric transformation relationship between the pixel coordinates of the image and the celestial coordinates. The WCS can map the pixel points on the original observation image to specific positions on the celestial sphere, so as to accurately determine the position of celestial bodies and the relative relationship between the original observation images.

[0042] Step S140, select any one of the series of sequential observation images after preprocessing and astronomical position calibration as the template image, where the remaining non-template images are scientific images.

[0043] Exemplarily, in the series of sequential observation images after preprocessing and astronomical position calibration, the first acquired image in the series of sequential observation images can be selected as the template image, or a non-first acquired image in the series of sequential observation images can be selected as the template image. After the template image is selected, the other images in the series of sequential observation images are all scientific images.

[0044] Step S150, perform background subtraction on the plurality of scientific images respectively in chronological order based on the template image.

[0045] In an embodiment of the present invention, background subtraction is performed on multiple scientific images based on a template image in chronological order, including: subtracting the template image from each of the multiple scientific images according to a preset observation time interval; after the subtraction, a first target in the template image and a second target in each of the multiple scientific images are obtained respectively. Among them, the first target and the second target are displayed as complementary colors in the image.

[0046] Specifically, the template image is used to perform stellar background subtraction on the scientific images in chronological order. For the two subtracted images, the interval time can be selected with reference to, for example, the target motion speed or the observation time interval to ensure that the object motion trajectory achieves an ideal effect.

[0047] Further, after the image subtraction is completed, only the first target in the template image (for example, the first target can be shown as a white target in the image) and the second target subtracted from the scientific image (for example, the second target can be shown as a complementary color (black) target in the image) remain.

[0048] Step S160: Superimpose and merge the template image with the multiple scientific images that have completed background subtraction based on the astronomical position to obtain a dynamic trajectory map.

[0049] Specifically, a series of images after image subtraction are superimposed based on the astronomical position, and then the characteristic trajectory of the second target is searched to construct a dynamic trajectory map formed by the first target and multiple second targets gathered together.

[0050] Exemplarily, the dynamic trajectory map can be shown as a dynamic trajectory map formed by white and a series of black dots or short lines gathered together.

[0051] Step S170: Identify fast-moving targets based on the dynamic trajectory map.

[0052] Specifically, based on the dynamic trajectory map, the time and position of the fast-moving target trajectory are extracted to obtain the fast-moving target.

[0053] Based on the above method for identifying fast-moving targets based on the complementary color characteristic trajectory, in an embodiment of the present invention, for the observation of fast-moving targets, a number of target images need to be continuously taken at intervals with the same exposure duration as the benchmark. Usually, the first image is used as the background reference template, called the template image, and the subsequent observed images are called the scientific images of this template image.

[0054] Further, the positions of the stars seen in the observed images are fixed in the astronomical coordinate system. The observed scientific images are respectively aligned with the template image based on the astronomical position, and the data of the two images are subtracted from each other. The remaining residual targets are the signals of the captured moving celestial bodies.

[0055] In an embodiment of the present invention, in order to ensure the anti-(black) color trajectory, a template image is needed to subtract the scientific image, and then several images with only fast-moving target celestial bodies are superimposed to obtain a clear motion trajectory of the fast-moving target. The first trajectory point of this characteristic trajectory is a white target, and the subsequent trajectory targets are all black, with extremely strong recognition. The trajectory feature image generated by the method of identifying fast-moving targets using the anti-color characteristic trajectory can not only ensure the uniqueness of extracting fast-moving targets, but also make the background of the constructed trajectory feature image purer, with almost no bright sources and other potential interferences, thus providing more accurate and stable recognition features, improving the efficiency and accuracy of recognition, and laying a solid foundation for the subsequent precise supervision of fast-moving targets.

[0056] Through the embodiments of the present invention, the interference of stellar bright sources and other backgrounds can be removed, and only the special anti-color characteristic trajectory of fast-moving targets can be constructed to achieve the rapid recognition of targets, ensuring the timely monitoring of fast-moving targets mainly including space debris targets and near-Earth asteroids, being able to detect critical moments in time and intervene in time to avoid losses of personnel and property.

[0057] Based on the above method of identifying fast-moving targets based on the anti-color characteristic trajectory, the present invention is illustrated with a series of sequential observation images as embodiments.

[0058] Figure 2 The template image according to the embodiment of the present invention is shown.

[0059] Obtain a series of sequential observation images containing fast-moving targets. This series of sequential observation images includes multiple original observation images in FITS format. Preprocess the multiple original observation images respectively, and then perform astronomical position calibration on the preprocessed multiple original observation images respectively. Select one of them as the template image. As Figure 2 shown, in this template image, the white target source within the green circle is a near-Earth asteroid, and the other white target sources are stars.

[0060] Figure 3 The scientific image according to the embodiment of the present invention is shown.

[0061] Furthermore, when the template image is selected, the other images in the series of sequential observation images are all scientific images. As Figure 3 shown, 3 scientific images selected from several scientific images are shown. The white target source within the green circle is a near-Earth asteroid, and the other white target sources are stars.

[0062] Figure 4 The images after background subtraction of the scientific images based on the template image according to the embodiment of the present invention are shown.

[0063] In an embodiment of the present invention, the scientific image is subtracted from the template image respectively to obtain three subtracted images. As Figure 4 shown, almost all the stars in the three subtracted images are subtracted completely, and the image only contains moving targets. See the green frames in the figure. The white target (i.e., the first target) in the frame is the near-Earth asteroid in the template image, and the black target (i.e., the second target) represents the near-Earth asteroid in the scientific image. Among the three green frames, the positions of the white dots remain unchanged, and the positions of the other near-Earth asteroids in the scientific image will change.

[0064] Figure 5 shows the image for obtaining the dynamic trajectory map by superposition according to an embodiment of the present invention.

[0065] Further, a series of images after image subtraction are superimposed based on the astronomical position, and then the characteristic trajectory of the second target is searched to construct a dynamic trajectory map formed by the first target and a plurality of second targets converging. As Figure 5 shown, the three images are superimposed into one image based on the astronomical position to obtain an anti-color characteristic trajectory of a near-Earth asteroid. See Figure 5 the green frame of the image, which is shown as a dynamic trajectory map composed of a white target and three black targets.

[0066] Figure 6 shows the effect diagram of the anti-color characteristic trajectory according to an embodiment of the present invention.

[0067] Further, Figure 6 is the effect diagram of the anti-color characteristic trajectories of different types of fast-moving targets. Figure 6 1 to 4 in it represent the anti-color characteristic trajectories of space debris targets, Figure 6 and 5 in it represents the anti-color characteristic trajectory of the near-Earth asteroid target. There are no other target interferences in the image except for the fast-moving targets, and it can achieve fast and accurate identification of fast-moving targets.

[0068] Through the embodiment of the present invention, the trajectory feature image generated by the method for identifying fast-moving targets using the anti-color characteristic trajectory can not only ensure the uniqueness of the extracted fast-moving targets, but also the background of the constructed trajectory feature image is purer, with almost no bright sources and other potential interferences, thereby providing more accurate and stable identification features and improving the efficiency and accuracy of identification.

[0069] The above specific embodiments have further detailed the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for identifying fast-moving targets based on inverted color feature trajectories, characterized in that: The method comprises: Acquire a series of time-series observation images containing fast-moving targets and establish an image database, wherein the series of time-series observation images include a plurality of original observation images; Preprocessing the multiple original observation images respectively; Perform astronomical position calibration on multiple pre-processed original observation images respectively; One of the time-series observation images after preprocessing and astronomical position calibration is selected as a template image, wherein the remaining images other than the template images are scientific images; Based on the template image, background subtraction is performed on a plurality of scientific images in chronological order; The template image after background subtraction is superimposed and merged with multiple scientific images based on astronomical positions to obtain a dynamic trajectory map; Based on the dynamic trajectory graph, identifying a fast-moving target; The step of performing background subtraction on the plurality of scientific images in chronological order based on the template image comprises: According to the preset observation time interval, the template image and the multiple scientific images are subjected to image subtraction; After the subtraction is completed, the first target in the template image and the second target in the plurality of scientific images are obtained respectively; The first target and the second target are displayed in the image in opposite colors; The template image after background subtraction is superimposed and merged with multiple scientific images based on astronomical positions to obtain a dynamic trajectory map, including: searching for a characteristic trajectory of the second target; Construct a dynamic trajectory graph including the first target and multiple second targets.

2. The method for identifying fast-moving targets based on inverse color feature trajectories according to claim 1, characterized in that: The series of time-series observation images includes at least 3 original observation images; and A plurality of original observation images in the series of time-series observation images are acquired according to a preset observation time interval.

3. The method for identifying fast-moving targets based on inverse color feature trajectories according to claim 1 or 2, characterized in that: The template image is the first image acquired in the series of time-series observation images.

4. The method for identifying fast-moving targets based on inverse color feature trajectories according to claim 1, characterized in that: The identifying of the fast-moving target based on the dynamic trajectory graph includes: Based on the dynamic trajectory graph, the time and position of the fast-moving target trajectory are extracted to obtain the fast-moving target.

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