Dynamic platform system for observing dynamic target feature establishment

Abstract

The invention discloses a system for observing dynamic target feature establishment by a dynamic platform, which comprises the following steps of: calculating a target relative projection speed according to target detection results of front and back frames; and target absolute projection speed: calculating the target absolute projection speed according to the target relative projection speed and the rotation speed of the observation platform. Calculating the length of a straight line segment which passes through the center position of the target and intersects with the target detection frame; the VRS characteristic value is obtained according to the calculated target projection body length and the calculated target absolute projection speed. The physical significance of the VRS characteristic value based on the target motion characteristic and the morphological characteristic is that the target moving distance in unit time is a multiple of the target body length, different types of moving targets can be effectively distinguished, and in the field of air specific type small target detection, target detection results are further screened by calculating the characteristic value, so that the target detection accuracy is improved. And the reliability of detection results is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic target observation, and particularly to a system for establishing dynamic target characteristics by a dynamic platform for observation. Background Art

[0002] Target detection is an important task in the field of computer vision, aiming to identify and locate target objects of interest from images or video sequences. Traditional target detection methods mainly rely on static features such as color, shape, or texture. However, these methods often fail to achieve ideal results when faced with complex and changing scenes. Target detection based on motion features utilizes the dynamic information of the target (such as position change, speed, acceleration, etc.) for detection. Because small and weak targets have small sizes and their morphological and texture features are not obvious, this method has broad application prospects in the field of small and weak target detection.

[0003] When observing dynamic targets by a dynamic platform, it is difficult to observe the texture and morphological features of the targets in the image, and their motion features are not reliable due to the movement of the platform and the presence of interfering objects. When the number of targets in the detection area is large and the types are complex, and the observation platform is continuously moving, the target detection algorithm based on motion features will be difficult to identify specific types of targets. For example, when identifying flying bird targets in the air, other small moving targets in the air will cause certain interference to target recognition. Therefore, it is necessary to study a new motion target feature to effectively distinguish different types of moving targets, improve the detection accuracy, and reduce the false alarm rate. Summary of the Invention

[0004] To solve the above deficiencies of the prior art, the present invention proposes a system for establishing dynamic target characteristics by a dynamic platform for observation.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions: A system for establishing dynamic target characteristics by a dynamic platform for observation includes the following steps.

[0006] Relative projection velocity of the target: Calculate the relative projection velocity of the target according to the target detection results of two consecutive frames.

[0007] Rotation speed of the observation platform: The rotation speed of the observation platform is the current speed of the observation platform.

[0008] Absolute projection velocity of the target: Calculate the absolute projection velocity of the target according to the relative projection velocity of the target and the rotation speed of the observation platform. The calculation formula is

[0009] Wherein, —— represents the absolute projection velocity of the target;

[0010] —— represents the relative projection speed of the target;

[0011] —— represents the speed of the observation platform;

[0012] The projected body length of the target: The projected body length of the target is obtained by calculating the length of the straight line segment passing through the center position of the target and intersecting the target detection frame;

[0013] The VRS eigenvalue: The VRS eigenvalue is obtained based on the calculated projected body length of the target and the calculated absolute projection speed of the target.

[0014] Further, the technical method of the relative projection speed of the target is as follows: According to the target detection results of two consecutive frames being (x 0 , y 0 ) and (x 1 , y 1 ), the relative projection speed of the target can be calculated by the calculation method.

[0015] Further, the calculation method of the projected body length of the target is as follows:

[0016] The straight line equation passing through the center of the target and along the target speed is:

[0017]

[0018] If the size of the target detection frame is w×h, the length of the intersection line segment between the straight line and the horizontal side line of the detection frame is

[0019]

[0020] The length of the intersection line segment between the straight line and the vertical side line of the detection frame is

[0021]

[0022] Based on this, the projected body length of the target can be obtained as

[0023] L = min(l x , l y ).

[0024] Further, the calculation method of the VRS eigenvalue is as follows:

[0025]

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: The VRS eigenvalue based on the target motion characteristics and morphological characteristics proposed by the present invention has a physical meaning that the distance traveled by the target per unit time is a multiple of the target body length, which can effectively distinguish different types of moving targets. In the field of detecting specific types of small targets in the air, by calculating this eigenvalue, the target detection results can be further screened to ensure the reliability of the detection results.

[0027] By introducing the motion speed of the observation platform, the speed information of the target in the field of view, and the target size information during feature calculation, the ratio of the target speed to the body length of the target along the motion direction (Velocity Ratio Size, VRS) is comprehensively calculated, and this ratio value is used as a new target feature. When observing a dynamic target on a dynamic platform, by calculating this target eigenvalue, the target detection results based on motion characteristics can be further screened, improving the reliability of the target detection results and effectively reducing the false alarm rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the projected body length of the target. DETAILED DESCRIPTION OF THE INVENTION

[0029] The present invention will be described in detail below with reference to the drawings and embodiments.

[0030] Embodiment 1

[0031] The implementation process of the present invention mainly includes three steps: calculating the absolute projected speed of the target, calculating the projected body length of the target, and calculating the VRS eigenvalue.

[0032] The first step is to calculate the absolute projected speed of the target.

[0033] This step calculates the absolute projected speed of the target according to the relative projected speed of the target and the rotation speed of the observation platform.

[0034] First, calculate the relative projected speed of the target according to the target detection results of two consecutive frames. If the target detection results of two consecutive frames are respectively (x 0 , y 0 ) and (x 1 , y 1 ), then the relative projected speed of the target can be calculated in the following way

[0035]

[0036] On this basis, combined with the current speed of the observation platform, the following can be calculated

[0037]

[0038] Where:

[0039] —— represents the target absolute projection velocity;

[0040] —— represents the target relative projection velocity;

[0041] —— represents the observation platform velocity;

[0042] When the velocity of the observation platform is random, the method of image registration can be used to calculate the inter-frame offset and obtain the rotational velocity of the observation platform.

[0043] The second step is to calculate the target projected body length, as Figure 1 shown.

[0044] The target projected body length is obtained by calculating the length of the straight-line segment passing through the target center position and intersecting the target detection frame.

[0045] The straight-line equation passing through the target center and along the target velocity is:

[0046]

[0047] If the size of the target detection frame is w×h, the length of the intersection line segment of the straight line and the horizontal side line of the detection frame is

[0048]

[0049] The length of the intersection line segment of the straight line and the vertical side line of the detection frame is

[0050]

[0051] Based on this, the target projected body length can be obtained as

[0052] L = min(l x , l y )

[0053] The third step is to calculate the VRS eigenvalue.

[0054]

[0055] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the patent and protection scope of the present invention should be subject to the appended claims.

Claims

1. A system for establishing dynamic target characteristics using a dynamic platform, characterized in that: The following steps are included: Target relative projection speed: Calculate the target relative projection speed based on the target detection results of the previous and next two frames; Rotation speed of the observation platform: The rotation speed of the observation platform is the current speed of the observation platform. Target absolute projection speed: The target absolute projection speed is calculated based on the target relative projection speed and the rotation speed of the observation platform. The calculation formula is: in, ——Indicates the absolute projection speed of the target; ——Indicates the relative projection speed of the target; ——Indicates the speed of the observation platform; Target projection length: The target projection length is obtained by calculating the length of the straight line segment that passes through the target center and intersects with the target detection frame; VRS eigenvalue: The VRS eigenvalue is obtained based on the calculated target projection length and the calculated target absolute projection speed.

2. A system for observing dynamic target characteristics using a dynamic platform as claimed in claim 1, characterized in that: The technical method of the target relative projection speed is as follows: according to the target detection results of the previous and next two frames are (x0, y0) and (x1, y1) respectively, the target relative projection speed can be Calculation method: Calculation.

3. A system for observing dynamic target characteristics using a dynamic platform as described in any one of claims 1 to 2, characterized in that: The target projection length is calculated as follows: The equation of the straight line passing through the center of the target and along the target velocity is: If the size of the target detection frame is w×h, then the length of the intersection of the straight line and the horizontal line of the detection frame is The length of the intersection of the straight line and the vertical line of the detection frame is On this basis, the target projection length can be obtained as follows: L=min(l x ,L y ) 4. A system for observing dynamic target characteristics using a dynamic platform as claimed in claim 3, characterized in that: The calculation method of VRS eigenvalue is as follows:

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