Video triggering method and device

Abstract

The invention relates to a video trigger method and a device. The video trigger method comprises the following steps: a trigger signal is output when vehicle characteristics are detected in a virtual coil of a video image, and the vehicle characteristics comprise the characteristics of vehicle bottom shadow. When the characteristics of vehicle bottom shadow are detected in the virtual coil of a video image, the output of the trigger signal comprises the following steps: pixel points in the virtual coil, which have a gray value smaller than or equal to a threshold of vehicle bottom shadow, are judged as characteristic points of vehicle bottom shadow; the trigger signal is output when the sum of the characteristic points of vehicle bottom shadow is larger than a first preset sum threshold. The invention can obtain a high trigger rate and a low error trigger rate.

Description

technical field [0001] The invention relates to the field of traffic control systems, in particular to a video trigger method and device for a vehicle monitoring and recording system. Background technique [0002] Vehicle monitoring and recording systems play an important role in traffic monitoring, traffic management, and social security. Vehicle monitoring and recording systems on the market use cameras installed on driveways to capture video images in real time. ) After capturing the video image, the video image including the vehicle is obtained, and then the system will automatically recognize the vehicle information such as the vehicle license plate from the captured video image. [0003] Vehicle triggering includes hardware triggering and video triggering. The ground sensing coil detector is commonly used for hardware triggering, and the ground sensing coil provides trigger information; video triggering uses the video signal provided by the camera to detect whether the...

AI Technical Summary

Problems solved by technology

The vehicle feature detected by this trigger method is the license plate feature. It cannot be triggered for vehicles without a license plate, and there are relatively many cases of false triggering due to interference from some areas of the body, railings, tree shadows and other background factors.

[0008] The above-mentioned triggering methods are limited by the characteristics of the vehicles they detect, so it is difficult to ensure a high trigger rate. Even if a high trigger rate can be guaranteed, it is easy to cause false triggering, resulting in an increase in the false trigger rate.

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