CN106534681A - Method for adaptively controlling cruising speed of photoelectric platform - Google Patents

Abstract

The invention relates to a method for controlling the cruising speed of a photoelectric platform. The method comprises the following steps: 1, providing a photoelectric platform of which the cruising speed is to be controlled and a camera arranged on the photoelectric platform, and inquiring a current focal distance f of the camera after setting a frame L of the camera; 2, determining a visual angle value of a camera lens according to the current focal distance of the camera; and 3, determining the cruising speed of the photoelectric platform according to the visual angle value of the camera lens. In the method, the camera is arranged on the photoelectric platform, and the photoelectric platform can adaptively adjust the cruising speed under the current focal distance f of the camera, so that monitoring personnel can obtain a high-quality image no matter how far a target is; operation errors can be reduced; the situations of target loss or blurring and the like due to image quality are reduced; and high-quality watching experience is provided for a user.

Description

The method of Self Adaptive Control photoelectric turntable cruising speed

Technical field

The present invention relates to a kind of method, especially a kind of method of Self Adaptive Control photoelectric turntable cruising speed, belongs to peace The technical field of anti-video monitoring.

Background technology

Video monitoring is the important component part of safety and protection system, with computer, network service and image procossing Etc. developing rapidly for technology, Video Supervision Technique there has also been significant progress.At present, Video Supervision Technique widely should Among every field, the especially field such as some public safeties, emergency command, such as state boundary management and control, strategic point are anti-safely Model, anti-terrorism search and rescue, customs preventive drug law enforcement, the monitoring of island ship, fight investigation, forest fire protection, airport, nuclear power station, oil field etc..

Photoelectric turntable can carry visible long-focus, near-infrared, LONG WAVE INFRARED and detect in integrally carrying out horizontal and vertical two Direction rotates, and is mainly used in longer-distance land, marine, aerial target is detected on a large scale, tracks, monitors and remembered Record.In the presence of control signal, the video camera on photoelectric turntable both can automatically scanning monitor area, also can be worth in Surveillance center Supervision object under the manipulation of class personnel；Therefore, photoelectric turntable be current border management and control, strategic point safety precaution, island ship monitoring, One of most common equipment of the protection and monitor fields such as forest fire protection, airport, nuclear power station, oil field.

Existing photoelectric turntable monitoring personnel is that monitoring personnel is logical controlling the photoelectric turntable of front end by consistency operation Cross photoelectric turntable of the daemon software transmitting control commands to front end, control the speed of turntable, the rotation direction of turntable, video camera The parameters such as focal length, so as to monitoring site, but this mode needs manual operation comparatively laborious and maloperation easily occurs；Example Such as when the moving target in monitoring is near apart from photographic head, the angular velocity that head pursuit movement target needs works as prison just than larger Moving target in control apart from photographic head it is remote when, the angular velocity that head pursuit movement target needs is just smaller.This far and near change The operation of change can allow monitoring personnel to be difficult to capture and track target in practice, so as to cause in video record because of picture quality And the target for causing is lost or smudgy.

The content of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art, there is provided a kind of Self Adaptive Control photoelectric turntable cruise The method of speed, which is easy to operate, can be according to the change of camera lens focal length, self-adaptative adjustment turntable speed, it is ensured that all the time High-quality picture quality can be provided, safety monitoring effect is improved, it is safe and reliable.

According to the technical scheme that the present invention is provided, a kind of method of Self Adaptive Control photoelectric turntable cruising speed, the control The method of photoelectric turntable cruising speed processed comprises the steps：

Step 1, photoelectric turntable and the video camera being installed on the photoelectric turntable that cruising speed to be controlled is provided, After setting the piece width L of the video camera, inquire about the photographic head when front focal length f；

Step 2, according to video camera when front focal length determines the visual angle value of camera lens, visual angle value VA is：

Wherein, VA is worth for visual angle, and piece width of the L for video camera, f work as front focal length for video camera；

Step 3, the cruising speed that photoelectric turntable is determined according to the visual angle value of determination camera lens, the photoelectric turntable Cruising speed V is：

Wherein, V is the cruising speed of photoelectric turntable, and k is proportionality coefficient, and 0 ＜ k≤1, VA are that visual angle is worth, and λ is frame per second.

Frame per second λ is 0.04.

The cruising speed of the photoelectric turntable with when the relation of front focal length f is：

Wherein, cruising speeds of the V for photoelectric turntable, k are proportionality coefficient, and 0 ＜ k≤1, L are the piece width of video camera, and f is to take the photograph Camera works as front focal length.

Advantages of the present invention：Video camera is installed on photoelectric turntable, and photoelectric turntable can be in video camera when under front focal length f It is adaptively adjusted cruising speed so that no matter target distance can obtain preferable image to monitoring personnel, it is possible to reduce operation On error, reduce situations such as target that picture quality causes is lost or be smudgy, provide higher to user The observation experience of quality.

Description of the drawings

Fig. 1 is the schematic diagram of relation between the lens focus of video camera of the present invention and visual angle.

Fig. 2 is the emulation schematic diagram of focal length of camera of the present invention and visual angle.

Fig. 3 is the emulation schematic diagram of camera angles of the present invention and turntable cruising speed.

Fig. 4 is the emulation schematic diagram of the focal length with turntable cruising speed of video camera of the present invention.

Specific embodiment

With reference to concrete drawings and Examples, the invention will be further described.

In order to be able to the change according to camera lens focal length, self-adaptative adjustment turntable speed, it is ensured that can provide all the time high-quality The picture quality of amount, improves safety monitoring effect, and the method for present invention control photoelectric turntable cruising speed comprises the steps：

Step 1, photoelectric turntable and the video camera being installed on the photoelectric turntable that cruising speed to be controlled is provided, After setting the piece width L of the video camera, inquire about the photographic head when front focal length f；

Specifically, the concrete structure of photoelectric turntable and it is installed on the concrete form of video camera on the photoelectric turntable and is Known to those skilled in the art, specifically repeat no more.The size at the photographic lenss visual angle of video camera, depends primarily on piece width L The length of (size of picture) and lens focus f.As chankings width L is fixed, then it is burnt that the size at visual angle is totally dependent on camera lens Away from the length of f.The relation at the video camera fixed to piece width L, focal length of camera and visual angle is as shown in figure 1, L is video camera in figure Piece width, unit are mm, 135 films such as popularized the most now, and its basic piece width is exactly 24 × 36mm, and cornerwise length is just 43.27mm is close to, then L herein just takes 43.27mm；Focal lengths of the f for video camera, unit is mm；θ is visual angle, unit for ° (spending).When being embodied as, for the video camera for determining, the piece width L of video camera keeps constant after determining；And current Jiao of video camera The working condition that video camera can be passed through to inquire about away from f is obtained, and specially known to those skilled in the art, here is omitted.

Step 2, according to video camera when front focal length determines the visual angle value of camera lens, visual angle value VA is：

Wherein, VA is worth for visual angle, and piece width of the L for video camera, f work as front focal length for video camera；

Specifically, explanation and the trigonometric function relation according to above-mentioned Fig. 1, then haveIt is possible thereby to derive Go outθ in formula is represented with VA.When obtain video camera when front focal length f when, it is possible to according to Above formula calculates the size of current visual angle VA.

Fig. 2 is, after visual angle value VA of camera lens is obtained when front focal length according to video camera, to emulate under MATLAB Function curve, x coordinate is focal length, and from 10mm to 800mm, y-coordinate is visual angle to scope, and scope is from 130 ° to 3 °, bent by function Line understands focal length with visual angle inversely, i.e. the focal length f of camera lens is shorter, then the visual angle of the camera lens is just wider；Conversely, camera lens Visual angle is just narrower.

Step 3, the cruising speed that photoelectric turntable is determined according to the visual angle value of determination camera lens, the photoelectric turntable Cruising speed V is：

Wherein, V is the cruising speed of photoelectric turntable, and k is proportionality coefficient, and 0 ＜ k≤1, VA are that visual angle is worth, and λ is frame per second.

Specifically, frame per second λ is the frame number of transmission per second, and frame number is the amount of the picture transmitted in 1 seconds, it is also possible to The number of times that graphic process unit can refresh each second is interpreted as, each frame is all static image, in extremely rapid succession shows frame just Define the illusion of motion.According to the eye storage characteristic of human eye, when object is in quick moving, when the image seen by human eye After disappearance, human eye remains to continue to retain its image image of 1/24 second or so, that is to say, that human eye is per second can to receive 24 frame figures Picture.Known human eye when comfortably loosening visual frame number be 24 frame per second, when concentrating on be less than 30 frames.

Assume the human eye image that can receive 25 frames per second, then the time required for each two field picture is 0.04 second. When camera acquisition image, when the visual angle value of video camera is VA, then each two field picture will be passed by 0.04 second It is worth the visual angle distance for k VA, i.e. λ=0.04, then has,Cruising speeds of the wherein V for photoelectric turntable, unit For °/s；VA be visual angle value, unit for °；K is proportionality coefficient, and scope is between 0 to 1；0.04 is the time that each frame is played.

Fig. 3 is the relation curve of the visual angle value with the rotational angular velocity (cruising speed) of photoelectric turntable of video camera, by function Curve understands that visual angle is proportional with angular velocity, i.e. the visual angle of camera lens is narrower, then the angular velocity of the turntable is less；Conversely, turning The angular velocity of platform is bigger.

By the relation between the visual angle value and the cruising speed of photoelectric turntable of video camera, then the angle of rotation speed of video camera is drawn Degree (the as cruising speed of photoelectric turntable) relation and between the focal length of video camera, i.e.,

Wherein, V for photoelectric turntable cruising speed, unit for °/s；Piece width of the L for video camera, unit is mm；F is shooting The focal length of machine, unit are mm；K is proportionality coefficient.

Fig. 4 for video camera focal length f and photoelectric turntable cruising speed between relation curve, the L values of the curve are 43.27mm, k value is 1, but the value of k is less than 1 in practice, understands the cruise of focal length f and photoelectric turntable by function curve Inversely, i.e. the focal length of photographic head is shorter for speed, then the cruising speed of the photoelectric turntable is less；Conversely, photoelectric turntable Cruising speed it is bigger.

Video camera of the present invention is installed on photoelectric turntable, and photoelectric turntable can be in video camera when self adaptation under front focal length f Ground adjusts cruising speed so that no matter target distance can obtain preferable image to monitoring personnel, it is possible to reduce operational mistake By mistake, reduce situations such as the target that picture quality causes is lost or be smudgy, better quality is provided to user Observation experience.

Claims (3)

1. a kind of method of Self Adaptive Control photoelectric turntable cruising speed, is characterized in that, the control photoelectric turntable cruising speed Method comprise the steps：

Step 1, photoelectric turntable and the video camera being installed on the photoelectric turntable that cruising speed to be controlled is provided, in setting After the piece width L of the video camera, inquire about the photographic head when front focal length f；

Step 2, according to video camera when front focal length determines the visual angle value of camera lens, visual angle value VA is：

$VA=\frac{2\·arctan\left(\frac{L}{2f}\right)\·360}{2\mathrm{\π}}$

Wherein, VA is worth for visual angle, and piece width of the L for video camera, f work as front focal length for video camera；

Step 3, the cruising speed that photoelectric turntable is determined according to the visual angle value of determination camera lens, the cruise of the photoelectric turntable Speed V is：

Wherein, V is the cruising speed of photoelectric turntable, and k is proportionality coefficient, and 0 ＜ k≤1, VA are that visual angle is worth, and λ is frame per second.

2. the method for Self Adaptive Control photoelectric turntable cruising speed according to claim 1, is characterized in that：Frame per second λ For 0.04.

3. the method for Self Adaptive Control photoelectric turntable cruising speed according to claim 2, is characterized in that：The photoelectricity turns The cruising speed of platform with when the relation of front focal length f is：

$V=\frac{9000\·k\·arctan\left(\frac{L}{2f}\right)}{\mathrm{\π}}$

Wherein, cruising speeds of the V for photoelectric turntable, k are proportionality coefficient, and 0 ＜ k≤1, L are the piece width of video camera, and f is video camera Work as front focal length.