A radar-guided video surveillance method

Abstract

The present invention discloses a radar-guided video surveillance method, comprising: locating a target entering a monitoring area by means of a radar, determining whether the target is close to a warning area and calculating an estimated warning duration of the target, evaluating the warning level of the target and marking a monitoring point selection period, calculating a selection performance value of a video monitoring point, marking a first tracking monitoring point and adjusting an angle to track the target, comparing the selection performance values of various video monitoring points within the monitoring point selection period and determining whether to switch the first tracking monitoring point, generating an alarm signal and entering a video tracking period when the target enters the warning area, calculating a loss risk value of the target in real time and determining whether the angle of the first tracking monitoring point needs to be adjusted and switched, if the target is lost, retrieving the target through other video monitoring points and switching the first tracking monitoring point, and if the target cannot be retrieved for a long time, marking the lost area and generating a maintenance optimization signal.

Description

Technical Field

[0001] The present invention relates to the technical field of video surveillance, and in particular to a radar-guided video surveillance method. Background Art

[0002] With the continuous advancement of science and technology, video surveillance technology has become an important means of security prevention in modern society. However, existing video surveillance systems have problems such as small monitoring range, many blind spots, and difficulty in target detection. These problems are particularly prominent in unmanned areas with complex geographical locations and wide distribution, such as borders, oil fields, and coasts.

[0003] In the existing technology, traditional video surveillance mainly relies on cameras to collect image information when the target approaches the warning area. However, the monitoring range of the camera is relatively fixed and limited. For distant targets, its position coordinates cannot be obtained in real time and accurately. It is impossible to timely sense the approach of the target when the target gradually approaches the warning area from a distance, which increases security risks.

[0004] In addition, in terms of the selection and adjustment of camera video monitoring points, traditional methods lack scientific and reasonable basis, and cannot fully utilize the dynamic information of the target to accurately evaluate the effectiveness and applicability of each video monitoring point for target tracking. When the target approaches the warning area, it is impossible to quickly and accurately select the best monitoring point from the many monitoring points to track the target. During the monitoring process, due to the constant changes in the target's motion state, traditional methods cannot reasonably switch the monitoring points and effectively adjust the camera angle according to these real-time changes. It is difficult to analyze the monitoring situation of the target in the video tracking process in real time, comprehensively and effectively. Once the target disappears from the monitoring screen, there is a lack of a fast and effective retrieval mechanism. If the target cannot be retrieved for a long time, it may not only cause a safety accident, but also fail to timely evaluate and optimize whether the layout of the monitoring system is reasonable and whether the equipment is operating normally, thereby restricting the improvement of the performance of the entire monitoring system.

[0005] In view of the above problems, the present invention proposes a radar-guided video surveillance method. Summary of the Invention

[0006] The object of the present invention is to provide a radar-guided video surveillance method to solve at least one of the above-mentioned problems in the prior art.

[0007] A radar-guided video surveillance method comprises the following steps:

[0008] The radar locates the target entering the monitoring area, obtains the target's position coordinates in real time, and judges whether the target is close to the warning area and calculates the target's expected warning time based on the change in the distance between the target's position coordinates and the warning area;

[0009] Evaluate the target's alert level based on the expected alert duration and mark the monitoring point selection period. Obtain the target's predicted alert coordinates and preset path and calculate the selection performance value of the video monitoring point. Mark the first tracking monitoring point based on the selection performance value and adjust the angle to track the target.

[0010] During the monitoring point selection period, the selection performance values of each video monitoring point are updated and compared in real time to determine whether to switch to the first tracking monitoring point. When the target enters the warning area, an alarm signal is generated and the video tracking period is marked;

[0011] During the video tracking period, the target's video tracking monitoring situation is analyzed in real time and the target's loss risk value is calculated. Based on the loss risk value, it is determined whether the angle of the first tracking monitoring point needs to be adjusted or switched;

[0012] If the target cannot be found in the monitoring image of the first tracking monitoring point during the video tracking period, a target lost signal is generated, the target is retrieved through other video monitoring points and the first tracking monitoring point is switched. If the target cannot be retrieved for a long time, the lost area is marked and a maintenance optimization signal is generated.

[0013] Beneficial effects of the present invention:

[0014] 1. The present invention uses radar to locate targets in real time and calculate the expected alert time, which can provide early warning of potential threats. Combining the predicted alert coordinates of the target with the preset path, the optimal video monitoring point is intelligently selected for tracking. This not only improves monitoring efficiency, but also ensures the accuracy and timeliness of monitoring, significantly enhances security prevention capabilities, and provides strong support for safety protection.

[0015] 2. The present invention updates and compares the selected performance values of video monitoring points in real time during the monitoring process, intelligently switches the tracking monitoring points, and ensures that the target is continuously and efficiently monitored. Once the target enters the warning area, an alarm is immediately triggered. By analyzing the tracking situation and calculating the loss risk in real time, the monitoring angle and switching of monitoring points are flexibly adjusted, effectively reducing the risk of target loss and improving the response speed and accuracy of the monitoring system.

[0016] 3. If the target is lost during the video tracking period, the present invention can respond quickly, use other video monitoring points to find the target and continue tracking to ensure monitoring continuity. If the target is not found for a long time, the system will mark the lost area and send a maintenance optimization signal to promptly guide maintenance and adjust the monitoring point position, effectively avoiding monitoring blind spots and improving overall monitoring efficiency and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a flowchart of the steps of a radar-guided video surveillance method provided by an embodiment of the present invention;

[0019] Figure 2 This is a flowchart of specific steps for obtaining the estimated alert duration in a radar-guided video surveillance method provided in Example 1 of the present invention;

[0020] Figure 3 This is a flowchart of specific steps for obtaining a loss risk value in a radar-guided video surveillance method provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0022] Example 1

[0023] like Figure 1 As shown, an embodiment of the present invention provides a radar-guided video surveillance method, which specifically includes the following steps:

[0024] Step 1: Use radar to locate the target entering the monitoring area, obtain the target's position coordinates in real time, and judge whether the target is close to the warning area based on the change in the distance between the target's position coordinates and the warning area, and calculate the target's expected warning time;

[0025] In some embodiments, a target entering a monitoring area is located by radar, where the monitoring area is an area artificially demarcated within the radar range where targets entering the area need to be monitored.

[0026] Specifically, the radar transmits high-frequency electromagnetic pulse signals through the antenna and receives the reflected echo signals through the receiving antenna. The target distance R is calculated, where t represents the time it takes for the radar signal to travel to and from the target, and c represents the speed of light, c = 3 × 10 8m / s, a two-dimensional plane coordinate system is established with the radar location as the origin, the horizontal east direction as the x-axis, and the horizontal north direction as the y-axis. The electronic scanning radar changes the direction of the beam by controlling the phase of the antenna array element, and determines the target's azimuth angle θ and pitch angle according to the beam pointing control parameters. The azimuth angle is defined as the angle rotated clockwise from the north direction, and the pitch angle is defined as the angle of the horizontal plane upward. Combined with the measured target distance R, the formula Calculate the position coordinates (x, y) of the target on the horizontal plane;

[0027] Based on any target entering the monitoring area, several monitoring time points are evenly selected within the monitoring period, and the intervals between adjacent monitoring time points are marked as monitoring intervals. The monitoring period represents the period of monitoring the target, and the duration of the monitoring intervals is the same;

[0028] At any point in time, the minimum distance between the target's position coordinates and the warning area at that point in time is obtained, which is marked as the warning distance. The warning area represents an area within the monitoring area that needs to be guarded against targets entering the area. Several cameras are set up in the warning area, marked as video monitoring points, to ensure that the monitoring range of all video monitoring points can cover the entire warning area.

[0029] like Figure 2 As shown, the specific steps for obtaining the estimated alert duration are as follows:

[0030] The radar obtains the target warning distance at the current monitoring time point and the previous adjacent monitoring time point and performs difference processing to obtain the target warning distance difference between the two monitoring time points;

[0031] If the warning distance difference is greater than or equal to 0, it means that the target is moving away from the warning area or has no tendency to approach the warning area, and a target not approaching signal is generated;

[0032] If the warning distance difference is less than 0, it means that the target is approaching the warning area and a target approach signal is generated;

[0033] If a target approach signal is generated, the obtained warning distance difference is compared with the duration of a monitoring interval to obtain the target's approach speed at the current monitoring time point. The target's warning distance at the current monitoring time point is compared with the obtained approach speed to obtain the target's estimated approach duration, which is marked as YJ.

[0034] Obtain the target's position coordinates at the current monitoring time point and the previous adjacent monitoring time point, connect the two position coordinates, mark the direction of the connecting line as the target's displacement direction at the current monitoring time point, and mark the target's position coordinates when it continues moving in the displacement direction until it enters the warning area as the target's predicted warning coordinates at the current monitoring time point;

[0035] Obtain the distance between the target's position coordinates at the current monitoring time point and the previous adjacent monitoring time point, and ratio it with the duration of a monitoring interval to obtain the target's displacement speed at the current monitoring time point. Obtain the distance between the target's position coordinates at the current monitoring time point and the predicted warning coordinates, and ratio it with the displacement speed to obtain the target's expected displacement duration, marked as YW.

[0036] The estimated approach time YJ and the estimated displacement time YW are processed, and the estimated alert time YS of the target at the current monitoring time point is calculated using the formula YS = a1*YJ + a2*YW, where a1 and a2 are preset proportional coefficients, a1 = 2.673, a2 = 1.311;

[0037] Step 2: Evaluate the target's alert level based on the expected alert duration and mark the monitoring point selection period. Obtain the target's predicted alert coordinates and preset path based on the target's position coordinate changes and calculate the selection performance value of the video monitoring point. Mark the first tracking monitoring point based on the selection performance value and adjust the angle to track the target.

[0038] In some embodiments, the target's alert level is evaluated based on the obtained estimated alert duration. Specifically, the obtained estimated alert duration of the target at the current monitoring time point is compared with an estimated alert duration threshold.

[0039] If the estimated alert duration is greater than or equal to the estimated alert duration threshold, it means that the probability of the target entering the alert area is low or the time required for the target to enter the alert area is long, and the target's alert level is low;

[0040] If the estimated alert duration is less than the estimated alert duration threshold, it means that the probability of the target entering the alert area is high and the time required for the target to enter the alert area is short, the target's alert level is high, and an early warning signal is generated;

[0041] Take a flag value fl ag and assign it a value of 0. If an early warning signal is generated and the fl ag value is 0, assign the fl ag value to 1, and mark the period when the fl ag value is continuously 1 as the monitoring point selection period;

[0042] When a warning signal is generated and the fl ag value is 0, the displacement direction and predicted warning coordinates of the target at the current monitoring time point are obtained, and the path along which the target still moves in the displacement direction after entering the warning area is marked as the preset path;

[0043] Get the monitoring range of the video surveillance points set in the warning area. For any video surveillance point, if the predicted warning coordinates are within the monitoring range of the video surveillance point, obtain the length of the portion of the preset path that overlaps with the monitoring range of the video surveillance point, and then compare it with the total length of the preset path to obtain the monitoring coverage ratio of the video surveillance point, marked as KF.

[0044] Obtain the position coordinates of the video surveillance point in the two-dimensional plane coordinate system, and calculate the distance between it and the predicted warning coordinates of the target at the current monitoring time point. Ratio the obtained distance value with the total length of the preset path to obtain the monitoring distance ratio of the video surveillance point, marked as KL;

[0045] The obtained monitoring coverage ratio KF and monitoring distance ratio KL are processed and the formula The selected performance value XB of the video surveillance point is calculated, where b1 and b2 are both preset proportional coefficients, where b1 = 3.696 and b2 = 1.473;

[0046] Calculate the selection performance values of all video surveillance points, sort them from largest to smallest based on their selection performance values, select the video surveillance point with the largest selection performance value, mark it as the first tracking surveillance point, and adjust the angle of the surveillance camera at the first tracking surveillance point so that the predicted warning coordinates are located at the center of the tracking surveillance point image;

[0047] The technical solution of an embodiment of the present invention is: to locate the target entering the monitoring area through radar, obtain the target's position coordinates in real time, judge whether the target is close to the warning area and calculate the target's expected warning time based on the change in the distance between the target's position coordinates and the warning area; evaluate the target's warning level based on the expected warning time and mark the monitoring point selection period, obtain the target's predicted warning coordinates and preset path based on the target's position coordinate changes and calculate the selection performance value of the video monitoring point, mark the first tracking monitoring point based on the selection performance value and adjust the angle to track the target.

[0048] Example 2

[0049] like Figure 1 As shown, the radar-guided video surveillance method provided by the embodiment of the present invention further includes the following steps:

[0050] Step 3: During the monitoring point selection period, the selection performance values of each video monitoring point are updated and compared in real time to determine whether to switch to the first tracking monitoring point. When the target enters the warning area, an alarm signal is generated and the video tracking period is entered;

[0051] In some embodiments, based on the marked monitoring point selection period, the predicted warning coordinates and preset path of the target at each monitoring time point are obtained in real time during the monitoring point selection period, and the selection performance value of each video monitoring point at the monitoring time point is calculated based on the predicted warning coordinates and the preset path;

[0052] Any monitoring time point after marking the first tracking monitoring point within the monitoring point selection period;

[0053] Sort the selection performance values of each video monitoring point at the monitoring time point from large to small, obtain the video monitoring point with the largest selection performance value, and mark it as the second tracking monitoring point;

[0054] Obtaining the selection performance values of the second tracking monitoring point and the first tracking monitoring point at the monitoring time point and performing difference processing to obtain the selection performance difference between the two at the monitoring time point;

[0055] Comparing the obtained selection performance difference value with the selection performance difference threshold;

[0056] If the selected performance difference is less than or equal to the selected performance difference threshold, it means that the selected performance value of the second tracking monitoring point is slightly different from that of the first tracking monitoring point, and there is no need to switch the selected first tracking monitoring point. The mark of the second tracking monitoring point is cleared to return it to a normal video monitoring point.

[0057] If the selected performance difference is greater than the selected performance difference threshold, it means that the selected performance value of the second tracking monitoring point is significantly different from that of the first tracking monitoring point. It is necessary to switch the selected first tracking monitoring point, clear the mark of the first tracking monitoring point to return it to a normal video monitoring point, and overwrite the second tracking monitoring point with the mark of the first tracking monitoring point.

[0058] Adjust the angle of the first tracking monitoring point so that the predicted warning coordinates of the target at the monitoring time point are relocated to the center of the tracking monitoring point screen;

[0059] In some embodiments, when the target appears in the image of the first tracking monitoring point, an alarm signal is generated and the flag value is assigned to 2, and the period in which the flag value is continuously 2 is marked as a video tracking period;

[0060] Based on the generated alarm signal, staff are arranged to handle the target entering the warning area, and the target is continuously tracked and monitored through video monitoring points during the video tracking period. When the target leaves the warning area, the fl ag value is assigned to 0;

[0061] It should be noted that the purpose of the fl ag value is to mark the starting and ending points of the monitoring point selection period and the video tracking period within the monitoring cycle;

[0062] Step 4: During the video tracking period, analyze the target's video tracking monitoring status in real time and calculate the target's loss risk value. Based on the loss risk value, determine whether the first tracking monitoring point needs to be adjusted or switched;

[0063] In some embodiments, based on the marked video tracking period, the video tracking monitoring situation of the target at each monitoring time point within the video tracking period is analyzed in real time;

[0064] like Figure 3 As shown, the specific steps for obtaining the loss risk value are as follows;

[0065] Specifically, based on the current monitoring time point within the video tracking period, the preset path of the target at the monitoring time point is obtained. At the same time, the monitoring area covered by the first tracking monitoring point at the current angle is obtained and marked as the sub-monitoring area of the first tracking monitoring point. The length of the preset path that overlaps with the sub-monitoring area is obtained and the length is compared with the length of the sub-monitoring area in the direction of the preset path to obtain the path overlap ratio of the sub-monitoring area, which is marked as LC.

[0066] Obtain the distance between the target's position coordinates and the position coordinates of the center point of the sub-monitoring area at the monitoring time point, mark it as the target deviation distance, and then compare it with the length of the sub-monitoring area in the preset path direction to obtain the target deviation ratio of the sub-monitoring area, marked as DJ;

[0067] The obtained path overlap ratio LC and target deviation ratio DJ are processed and the formula The loss risk value DQ is calculated, where s1 and s2 are preset proportional coefficients, s1 = 2.333, s2 = 3.142;

[0068] Compare the obtained loss risk value with the loss risk value threshold;

[0069] If the target's loss risk value at the monitoring time point is less than or equal to the loss risk value threshold, it means that there is no need to adjust the angle or switch the first tracking monitoring point temporarily;

[0070] If the target loss risk value at the monitoring time point is greater than the loss risk value threshold, it indicates that the first tracking monitoring point needs to be adjusted or switched, and a monitoring point adjustment signal is generated;

[0071] Based on the generated monitoring point adjustment signal, if the target can be positioned at the center of the first tracking monitoring point image by adjusting the angle, then adjusting the angle of the first tracking monitoring point;

[0072] If the target's location has exceeded the range that can be reached by adjusting the angle of the first tracking monitoring point and the target cannot be placed in the center of the first tracking monitoring point image by adjusting the angle, the target's location coordinates when it moves out of the sub-monitoring area along the preset path at the monitoring time point are marked as predicted warning coordinates;

[0073] Calculate the selection performance value of each video surveillance point at the monitoring time point based on the predicted warning coordinates of the target at the monitoring time point and the preset path, and sort the video surveillance points from large to small according to the selection performance value. Obtain the video surveillance point with the largest selection performance value and mark it as the third tracking monitoring point;

[0074] Adjust the angle of the third tracking monitoring point so that the predicted warning coordinates are located at the center of the third tracking monitoring point's sub-monitoring area. When the target appears in the third tracking monitoring point's image, clear the mark of the first tracking monitoring point to return it to a normal video monitoring point, and overwrite the third tracking monitoring point with the mark of the first tracking monitoring point.

[0075] It should be noted that the purpose of the above steps is to continuously and seamlessly track and monitor the target during the video tracking period to prevent the target from being lost due to angle adjustment and switching of the video monitoring point;

[0076] The technical solution of an embodiment of the present invention is: during the monitoring point selection period, the selection performance value of each video monitoring point is updated and compared in real time and a judgment is made as to whether to switch the first tracking monitoring point. When the target enters the warning area, an alarm signal is generated and the video tracking period is entered. During the video tracking period, the video tracking monitoring situation of the target is analyzed in real time and the loss risk value of the target is calculated. Based on the loss risk value, it is judged whether the angle of the first tracking monitoring point needs to be adjusted and switched.

[0077] Example 3

[0078] like Figure 1 As shown, the radar-guided video surveillance method provided by the embodiment of the present invention further includes the following steps:

[0079] Step 5: If the target cannot be found in the monitoring image of the first tracking monitoring point during the video tracking period, a target loss signal is generated, the target is retrieved through other video monitoring points and the first tracking monitoring point is switched. If the target cannot be retrieved for a long time, the lost area is marked and a maintenance optimization signal is generated;

[0080] In some embodiments, based on the first tracking monitoring point marked during the video tracking period, a monitoring picture of the first tracking monitoring point is acquired in real time at the monitoring time point, and the monitoring picture is analyzed;

[0081] If the target cannot be found in the monitoring image, a target loss signal is generated, a flag value num is taken and assigned to 0. If a target loss signal is generated and the num value is 0, the num value is assigned to 1, and the period in which the num value is continuously 1 is marked as a target loss period;

[0082] It should be noted that the num value is used to mark the start and end points of each target loss period within the video tracking period;

[0083] It should be noted that during the video tracking period, the first tracking monitoring point always follows the target's position coordinates and performs angle adjustments or video monitoring point switching. Therefore, the target should always appear in the monitoring image of the first tracking monitoring point during the video tracking period. If the target cannot be found in the monitoring image, it may be because there is an obstacle blocking the monitoring image within the sub-monitoring area of the first tracking monitoring point at that time, or it may be that the first tracking monitoring point itself is faulty or blocked.

[0084] When the target loss signal is generated and the num value is 0, the selection performance values of all video monitoring points at the current monitoring time point are obtained, and the video monitoring points with non-zero selection performance values are sorted from large to small according to the selection performance value;

[0085] During this target loss period, the angles of the video monitoring points are adjusted in sequence according to the sorting order so that the target's position coordinates at the current monitoring time point are located in the center of the sub-monitoring area, while still tracking the target's position coordinates through the first tracking monitoring point;

[0086] When a target is identified in the monitoring image of any video monitoring point, a target retrieval signal is generated and the num value is assigned to 0;

[0087] If the video monitoring point where the target is identified in the monitoring screen is the first tracking monitoring point, there is no need to switch the first tracking monitoring point;

[0088] If the video surveillance point where the target is identified in the monitoring image is not the first tracking surveillance point, the mark of the first tracking surveillance point is cleared to return it to a normal video surveillance point, and the video surveillance point where the target is identified at this time is marked as the first tracking surveillance point;

[0089] It should be noted that the performance value of the target is 0 only when the preset path of the target does not overlap with the monitoring range of the video monitoring point at the monitoring time point. Therefore, there is no need to analyze the video monitoring point with a performance value of 0.

[0090] Obtain the duration of the current target loss period and compare it with the loss period threshold. When the target loss period is equal to the loss period threshold, it means that no video surveillance point that can track and monitor the target can be found in the warning area for a long time. The area where the target passes during the target loss period is marked as a lost area, and a maintenance optimization signal is generated.

[0091] According to the generated maintenance optimization signal and the lost area, the video surveillance points in the warning area are repaired and the positions of the video surveillance points are adjusted so that the lost area can be identified by the monitoring screen of the video surveillance points, thus preventing the existence of blind spots in the warning area that cannot be monitored;

[0092] The technical solution of an embodiment of the present invention is: if the target cannot be found in the monitoring screen of the first tracking monitoring point during the video tracking period, a target lost signal is generated, the target is retrieved through other video monitoring points and the first tracking monitoring point is switched. If the target cannot be retrieved for a long time, the lost area is marked and a maintenance optimization signal is generated to repair the video monitoring points in the warning area and adjust the positions of the video monitoring points.

[0093] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0094] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A radar-guided video surveillance method, characterized in that: The following steps are involved: The radar locates the target entering the monitoring area, obtains the target's position coordinates in real time, and judges whether the target is close to the warning area and calculates the target's expected warning time based on the change in the distance between the target's position coordinates and the warning area; Evaluate the target's alert level based on the expected alert duration and mark the monitoring point selection period. Obtain the target's predicted alert coordinates and preset path and calculate the selection performance value of the video monitoring point. Mark the first tracking monitoring point based on the selection performance value and adjust the angle to track the target. The specific method for obtaining the estimated alert duration is as follows: If a target approach signal is generated, the obtained warning distance difference and the duration of a monitoring interval are processed to obtain the estimated approach duration of the target, which is marked as YJ; Obtain the target's position coordinates at the current monitoring time point and the previous adjacent monitoring time point, and analyze the two together with the warning area to obtain the target's predicted warning coordinates at the current monitoring time point; Obtain the distance between the target's position coordinates at the current monitoring time point and the previous adjacent monitoring time point, and the distance between the target's position coordinates at the current monitoring time point and the predicted warning coordinates. Perform data processing to obtain the target's estimated displacement duration, which is marked as YW. The estimated approach time YJ and the estimated displacement time YW are processed to calculate the estimated alert time of the target at the current monitoring time point; The specific method of obtaining the first tracking monitoring point is: Obtain the target's displacement direction and predicted warning coordinates at the current monitoring time point, and mark the path along which the target continues to move after entering the warning area as the preset path; Obtain the monitoring range of the video surveillance points set in the warning area. For any video surveillance point, if the predicted warning coordinates are within the monitoring range of the video surveillance point, analyze the preset path and monitoring range, and calculate the monitoring coverage ratio of the video surveillance point, which is marked as KF. Obtain the location coordinates of the video surveillance point and the predicted warning coordinates of the target and analyze them to calculate the monitoring distance ratio of the video surveillance point, marked as KL; The obtained monitoring coverage ratio KF and monitoring distance ratio KL are processed to calculate the selection performance value of the video monitoring point; Calculate the selection performance values of all video monitoring points, sort the video monitoring points from large to small according to the selection performance value, select the video monitoring point with the largest selection performance value, and mark it as the first tracking monitoring point; During the monitoring point selection period, the selection performance values of each video monitoring point are updated and compared in real time to determine whether to switch to the first tracking monitoring point. When the target enters the warning area, an alarm signal is generated and the video tracking period is marked; During the video tracking period, the target's video tracking monitoring situation is analyzed in real time and the target's loss risk value is calculated. Based on the loss risk value, it is determined whether the angle of the first tracking monitoring point needs to be adjusted or switched; If the target cannot be found in the monitoring image of the first tracking monitoring point during the video tracking period, a target lost signal is generated, the target is retrieved through other video monitoring points and the first tracking monitoring point is switched. If the target cannot be retrieved for a long time, the lost area is marked and a maintenance optimization signal is generated.

2. The radar-guided video surveillance method according to claim 1, characterized in that: The specific method of obtaining the target approach signal is as follows: Based on any target entering the monitoring area, several monitoring time points are evenly selected within the monitoring period, and the interval between adjacent monitoring time points is marked as the monitoring interval period; At any point in time, the minimum distance between the target's position coordinates and the warning area at that point in time is obtained, marked as the warning distance, and several cameras are set up in the warning area, marked as video monitoring points; The radar obtains the target warning distance at the current monitoring time point and the previous adjacent monitoring time point and performs difference processing to obtain the target warning distance difference between the two monitoring time points. If the warning distance difference is less than 0, a target approach signal is generated.

3. The radar-guided video surveillance method according to claim 1, characterized in that: The specific method for obtaining the monitoring point selection period and video tracking period is as follows: The estimated alert time of the target at the current monitoring time point is compared with the estimated alert time threshold. If the estimated alert time is less than the estimated alert time threshold, an early warning signal is generated. Take a flag value flag and assign it a value of 0. If an early warning signal is generated and the flag value is 0, assign the flag value to 1, and mark the period when the flag value is continuously 1 as the monitoring point selection period; When the target appears in the picture of the first tracking monitoring point, an alarm signal is generated and the flag value is assigned to 2. When the target leaves the warning area, the flag value is assigned to 0. The period when the flag value remains 2 is marked as the video tracking period.

4. The radar-guided video surveillance method according to claim 1, characterized in that: The specific method of determining whether to switch the first tracking monitoring point is: Based on the marked monitoring point selection period, the selection performance value of each video monitoring point of the target at each monitoring time point is obtained in real time during the monitoring point selection period; Any monitoring time point after marking the first tracking monitoring point within the monitoring point selection period; Sort the selection performance values of each video monitoring point at the monitoring time point from largest to smallest, obtain the video monitoring point with the largest selection performance value, mark it as the second tracking monitoring point, obtain the selection performance value of the second tracking monitoring point and the first tracking monitoring point at the monitoring time point, and perform difference processing to obtain the selection performance difference between the two at the monitoring time point; Comparing the obtained selection performance difference value with the selection performance difference threshold; If the selected performance difference is less than or equal to the selected performance difference threshold, the mark of the second tracking monitoring point is cleared to return it to a normal video monitoring point. If the selected performance difference is greater than the selected performance difference threshold, the mark of the first tracking monitoring point is cleared to return it to a normal video monitoring point, and the second tracking monitoring point at this time is overwritten and marked as the first tracking monitoring point.

5. The radar-guided video surveillance method according to claim 1, characterized in that: The specific method of determining whether the angle adjustment and switching of the first tracking monitoring point is required is: The obtained loss risk value is compared with the loss risk value threshold. If the loss risk value of the target at the monitoring time point is greater than the loss risk value threshold, a monitoring point adjustment signal is generated; Based on the generated monitoring point adjustment signal, if the target can be positioned at the center of the first tracking monitoring point image by adjusting the angle, the angle of the first tracking monitoring point is adjusted. If the target's location has exceeded the range covered by the angle adjustment of the first tracking monitoring point and the target cannot be positioned at the center of the first tracking monitoring point image by adjusting the angle, the position coordinates of the target at the monitoring time point when it moves out of the sub-monitoring area along the preset path are marked as predicted warning coordinates; Calculate the selection performance value of each video monitoring point at the monitoring time point based on the predicted warning coordinates of the target at the monitoring time point and the preset path, obtain the video monitoring point with the largest selection performance value, and mark it as the third tracking monitoring point; Adjust the angle of the third tracking monitoring point so that the predicted warning coordinates are located in the center of the monitoring area of the third tracking monitoring point. When the target appears in the picture of the third tracking monitoring point, clear the mark of the first tracking monitoring point to return it to a normal video monitoring point, and overwrite the third tracking monitoring point with the mark of the first tracking monitoring point.

6. The radar-guided video surveillance method according to claim 5, characterized in that: The specific method of obtaining the loss risk value is as follows: Based on the current monitoring time point within the video tracking period, the preset path of the target at the monitoring time point is obtained. At the same time, the monitoring area covered by the first tracking monitoring point at the current angle is obtained and marked as the sub-monitoring area of the first tracking monitoring point. The two are analyzed and calculated to obtain the path overlap ratio of the sub-monitoring area, marked as LC; Obtain the target's position coordinates at the monitoring time point and analyze them with the sub-monitoring area of the first tracking monitoring point, and calculate the target deviation ratio of the sub-monitoring area, which is marked as DJ; The obtained path overlap ratio LC and target deviation ratio DJ are processed to calculate the loss risk value.

7. The radar-guided video surveillance method according to claim 1, characterized in that: The specific method of obtaining the maintenance optimization signal is as follows: Acquire the monitoring image of the first tracking monitoring point in real time during the video tracking period. If the target cannot be found in the monitoring image, generate a target lost signal, take a flag value num and assign it a value of 0. If the target lost signal is generated and the num value is 0, assign the num value to 1. If the target is identified in the monitoring image of any video monitoring point and the num value is 1, assign the num value to 0. Mark the period in which the num value is continuously 1 as a target lost period. The duration of the current target loss period is obtained and compared with the loss period threshold. When the duration of the target loss period is equal to the loss period threshold, a maintenance optimization signal is generated.

8. The radar-guided video surveillance method according to claim 7, characterized in that: The specific method of retrieving the target and switching to the first tracking monitoring point is: Obtain the selected performance values of all video surveillance points at the current monitoring time point, and sort the video surveillance points whose selected performance values are not 0 from large to small according to the selected performance values; During this target loss period, the angles of the video monitoring points are adjusted in sequence according to the sorting order so that the target's position coordinates at the current monitoring time point are located in the center of the sub-monitoring area, while still tracking the target's position coordinates through the first tracking monitoring point; If the video surveillance point where the target is identified in the monitoring image is not the first tracking surveillance point, the mark of the first tracking surveillance point is cleared to return it to an ordinary video surveillance point, and the video surveillance point where the target is identified at this time is marked as the first tracking surveillance point.

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