Quick positioning and focusing method, system and equipment for visible light telephoto lens

Abstract

The invention discloses a rapid positioning and focusing method for a visible light telephoto lens, and relates to the monitoring technology, and the method comprises the steps: installing a photoelectric device with a telephoto visible light lens on a target monitoring tower in advance, and installing a monitoring ball machine below the monitoring tower; under the condition that the view field angle of the long-focus visible light lens of the photoelectric equipment is zoomed to the minimum value, the long-focus visible light lens is used for observing targets at different distances at the specified environment temperature; recording focusing potentiometer feedback values corresponding to the clear points of the target at different distances to form a relation curve between the target distance and the focusing potentiometer feedback values of the clear points of the target at the distance; determining a focusing value range of the long-focus visible light lens according to the relation curve; and under the condition of automatic focusing, positioning focusing is controlled according to the focusing value range. According to the embodiment of the invention, the success probability of automatic focusing can be greatly improved by combining the improved rapid focusing method with the high tower installation and use environment and actual observation requirements of the equipment.

Description

Technical Field

[0001] The present application relates to the field of monitoring technology, and in particular to a method, system and device for quickly positioning and focusing a visible light telephoto lens. Background Art

[0002] With the passage of time, video surveillance towers are increasingly being deployed along national borders, forming comprehensive surveillance systems. The speed and success rate of the autofocusing of the visible light telephoto lenses used in the optoelectronic equipment installed on these towers directly determine the effectiveness of the system's observations.

[0003] The autofocus speed of the visible light telephoto lens also needs to be further improved.

[0004] The optoelectronic equipment installed on the video surveillance tower takes a long time to focus automatically when using a telephoto visible light lens. At the same time, due to long-distance observation, the image is more easily affected by atmospheric turbulence, resulting in a low success rate of automatic focusing. Summary of the Invention

[0005] The embodiments of the present application provide a method, system, and device for quickly positioning and focusing a visible light telephoto lens. The improved rapid focusing method is combined with the high-tower installation and use environment of the equipment and actual observation needs to improve the success rate of automatic focusing.

[0006] The present invention provides a method for quickly positioning and focusing a visible light telephoto lens, comprising:

[0007] Install optoelectronic equipment with long-focus visible light lenses and surveillance cameras in the target monitoring tower in advance;

[0008] When the telephoto visible light lens of the optoelectronic device is zoomed to the minimum field of view, observe targets at different distances with the telephoto visible light lens at the specified ambient temperature.

[0009] Record the focus potentiometer feedback values ​​corresponding to the target's clear points at different distances to form a relationship curve between the target distance and the focus potentiometer feedback value of the target's clear point at the distance;

[0010] determining a focus value range of the telephoto visible light lens according to the relationship curve;

[0011] In the case of automatic focusing, positioning and focusing are controlled according to the focus value range.

[0012] An embodiment of the present application also provides a visible light telephoto lens rapid positioning and focusing system, which is used to pre-install optoelectronic equipment on a target monitoring tower. The positioning and focusing system includes a processor and a memory, and the memory stores a computer program. When the computer program is executed by the processor, the steps of the visible light telephoto lens rapid positioning and focusing method as described above are implemented.

[0013] An embodiment of the present application also provides a monitoring device, which is pre-installed on a target monitoring tower. The monitoring device includes a processor and a memory, and a computer program is stored on the memory. When the computer program is executed by the processor, the steps of the aforementioned visible light telephoto lens rapid positioning and focusing method are implemented.

[0014] The embodiment of the present application adopts an improved fast focusing method combined with the high-tower installation and use environment of the equipment and actual observation needs, which can greatly improve the success probability of automatic focusing.

[0015] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0017] Figure 1 This is a schematic diagram of the basic process of the method for rapid positioning and focusing of a visible light telephoto lens according to an embodiment of the present application;

[0018] Figure 2 This is an application example of the method for quickly positioning and focusing a visible light telephoto lens according to an embodiment of the present application. DETAILED DESCRIPTION

[0019] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0020] The present application provides a method for quickly positioning and focusing a visible light telephoto lens. Figure 1 As shown, the following steps are included:

[0021] In step S101, optoelectronic equipment and a surveillance camera are pre-installed on the target monitoring tower. In some embodiments, pre-installing optoelectronic equipment on the target monitoring tower includes: configuring the target tower height to meet requirements; and installing the optoelectronic equipment and the surveillance camera on the target monitoring tower so that the optoelectronic equipment's telephoto lens can observe targets outside the surveillance camera's monitoring range. In a specific example, the long-distance monitoring optoelectronic equipment uses a telephoto lens, and the long-distance monitoring optoelectronic equipment is installed on a video surveillance watchtower. The height of a video surveillance watchtower is generally around 20 meters, and a surveillance camera is installed below the tower. The monitoring range of an outdoor camera is generally 200 meters. The telephoto lens can observe targets beyond 200 meters to meet usage requirements.

[0022] In step S102, when the field of view angle of the telephoto visible light lens of the surveillance camera is magnified to the minimum value, the telephoto visible light lens is used to observe targets at different distances under a specified ambient temperature. In some embodiments, the specified ambient temperature is 20°C-30°C, for example, 25°C.

[0023] In a specific example, taking a telephoto lens with a focal length of 1200mm as an example, the feedback value range of the lens focus potentiometer is 200-3900. When the lens field of view angle is zoomed to the minimum value, at an ambient temperature of 25°C, the telephoto lens is used to observe targets at different distances.

[0024] In step S103, the focus potentiometer feedback values ​​corresponding to the target's clear point at different distances are recorded to form a relationship curve between the target distance and the focus potentiometer feedback value of the target's clear point at that distance. For example, based on the above example, the focus potentiometer feedback values ​​corresponding to the target's clear point at different distances are recorded to form a function curve between the target distance and the focus potentiometer feedback value of the target's clear point at that distance.

[0025] In step S104, the focus range of the telephoto visible light lens is determined based on the relationship curve. Further based on the above example, the function curve determines that a focal length of 200 meters corresponds to a focal length of 1200. Therefore, the effective focus range of the telephoto visible light lens installed on a high tower is 200-1200.

[0026] In step S105 , in the case of automatic focusing, positioning and focusing are controlled according to the focus value range.

[0027] In some embodiments, in the case of automatic focusing, controlling positioning and focusing according to the focus value range includes:

[0028] First, the lens focus motor is controlled to run at a maximum speed to a middle range position of the focus value range.

[0029] Perform focusing motion within the focus value range to find a clear point. Figure 2As shown, in a specific example, based on the aforementioned example, during automatic focusing, the lens focus motor can first run at the maximum speed to a focal length value of 600, and then perform focusing movement within the range of 200-1200 to find a clear point.

[0030] In some embodiments, in the case of automatic focusing, controlling the positioning focus according to the focus value range further includes performing the following process when performing the focusing movement to find a clear point:

[0031] Redundancy judgment is added to judge the image clarity trend, wherein a threshold is set to judge whether the clarity increases or decreases. When the difference in the focus evaluation function values ​​of the two frames is greater than the threshold Z1, it is judged as a clarity decreasing trend. When the difference in the focus evaluation function values ​​of the two frames is less than the threshold Z2, it is judged as a clarity increasing trend. In this way, autofocus can be achieved quickly and the success rate of autofocus is improved.

[0032] This method utilizes an improved rapid focusing method, combined with the equipment's high-tower installation and use environment and actual observation needs. Based on the relationship between target distance and the feedback value of the focus potentiometer at the target's clear point at that distance, the lens's focus motor first rotates to the middle of the effective focus range during autofocus, and then automatically focuses within the specified range. Furthermore, a threshold value is used to determine the target's clear point during the search, increasing the probability of autofocus success.

[0033] An embodiment of the present application also provides a visible light telephoto lens rapid positioning and focusing system, which is applied to a monitoring system in which optoelectronic equipment and a monitoring dome camera are pre-installed on a target monitoring tower. The positioning and focusing system includes a processor and a memory, and a computer program is stored on the memory. When the computer program is executed by the processor, the steps of the visible light telephoto lens rapid positioning and focusing method as described above are implemented.

[0034] An embodiment of the present application also provides a monitoring device, which is pre-installed on a target monitoring tower. The monitoring device includes a processor and a memory, and a computer program is stored on the memory. When the computer program is executed by the processor, the steps of the aforementioned visible light telephoto lens rapid positioning and focusing method are implemented.

[0035] It should be noted that, in the various embodiments of the present application, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0036] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0037] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in each embodiment of the present application.

[0038] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are protected by this application.

Claims

1. A method for quickly positioning and focusing a visible light telephoto lens, characterized in that: include: Install photoelectric equipment and surveillance cameras on the target monitoring tower in advance; When the telephoto visible light lens of the optoelectronic device is zoomed to the minimum field of view, observe targets at different distances with the telephoto visible light lens at the specified ambient temperature. Record the focus potentiometer feedback values ​​corresponding to the target's clear points at different distances to form a relationship curve between the target distance and the focus potentiometer feedback value of the target's clear point at the distance; determining a focus value range of the telephoto visible light lens according to the relationship curve; In the case of automatic focusing, positioning and focusing are controlled according to the focus value range.

2. The method for quickly positioning and focusing a visible light telephoto lens according to claim 1, wherein: The optoelectronic equipment and surveillance cameras installed on the target monitoring tower in advance include: Configure the target tower height to meet the requirements; Photoelectric equipment is installed on the target monitoring tower so that the telephoto visible light lens of the photoelectric equipment can observe targets outside the monitoring range of the surveillance camera.

3. The method for rapid positioning and focusing of a visible light telephoto lens according to claim 1, wherein: The specified ambient temperature is 20°C-30°C.

4. The method for rapid positioning and focusing of a visible light telephoto lens according to claim 1, wherein: In the case of automatic focusing, controlling positioning and focusing according to the focus value range includes: First, the lens focusing motor is controlled to run at the maximum speed to a middle range position of the focusing value range; A focus movement is performed within the focus value range to find a sharp point.

5. The method for rapid positioning and focusing of a visible light telephoto lens according to claim 4, wherein: In the case of automatic focusing, controlling the positioning and focusing according to the focus value range also includes performing the following process when performing the focusing movement to find a clear point: Redundancy judgment is added to judge the image clarity trend, in which a threshold is set to judge whether the clarity increases or decreases. When the difference in the focus evaluation function value of the two frames is greater than the threshold Z1, it is judged as a clarity decreasing trend. When the difference in the focus evaluation function value of the two frames is less than the threshold Z2, it is judged as a clarity increasing trend.

6. A visible light telephoto lens rapid positioning and focusing system, characterized in that: A monitoring system for pre-installing optoelectronic equipment on a target monitoring tower, wherein the positioning and focusing system includes a processor and a memory, wherein the memory stores a computer program that, when executed by the processor, implements the steps of the method for rapid positioning and focusing of a visible light telephoto lens according to any one of claims 1 to 5.

7. A monitoring device, characterized in that: The monitoring device is pre-installed on a target monitoring tower. The monitoring device includes a processor and a memory. The memory stores a computer program. When the computer program is executed by the processor, the steps of the method for rapid positioning and focusing of a visible light telephoto lens are implemented as described in any one of claims 1 to 5.

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