Video fogging effect is significant

When security requirements evolve from passive detection to active defense, various image processing algorithms relying on intelligent analysis become important. Among them, fog-through processing integrates multiple image algorithms and is an important class of image processing technology. In order to obtain better processing results, the camera manufacturers will add a special image processing chip, the chip will read the video stream information in real time, determine whether to open the fog mode by comparing the parameters, that is, can automatically detect the fog, or even through The set preset mode determines the fog level and selects the corresponding fog mode.

The effect of fog on video surveillance is generally believed to be that atmospheric media consists mainly of air molecules, moisture, and aerosols. Aerosols are dispersions of small particles suspended in a gas. Some particles have high hygroscopicity and act as a vapor condensation center, the size of which is related to the relative humidity of the environment, the supply of water vapor, and the extent to which condensation occurs due to collisions. Due to differences in the size, type, and degree of aggregation of various particles in the atmosphere, various weather conditions such as clear weather, haze, fog, clouds, and rain are generated.

In sunny weather conditions, the light reflected from the surface of the object is not likely to be scattered, absorbed or reflected by various components of the atmosphere, and can directly reach the imaging device to obtain a clear and fog-free image.

In foggy weather, light reflected from the surface of an object is affected by suspended particles in the air during its arrival in the imaging device. Aerosol particles are the main factor for the formation of haze, and they are also the root cause of the degradation of image quality. The effects are mainly in the following aspects:

Aerosol particles have a scattering effect on the light, and the scattering loss attenuates the intensity of the "transmitted light", resulting in a decrease in the contrast of the image. Due to the non-uniformity of the aerosol particles, the spherical wave is distorted into an aspherical wave, resulting in blurred images and reduced edges and details. The particle size of the aerosol particles is large, and the self-imaging of the particles cannot be ignored and can be approximately understood as “noise”. The scattering of the imaging light by the aerosol particles will be imaged by the multiple scattering and the original forward scattering part to form a certain blur.

Video fogging technology security application effect is significant Real-time video fogging technology can improve the quality of video surveillance from multiple perspectives. First of all, it is a fog-permeable technology that can be used for aerosol treatment of various weather conditions caused by aerosols; it is also an enhancement algorithm that can significantly increase the contrast of images, make images transparent and clear, and can significantly enhance The detailed information of the image makes the details of the originally hidden image fully displayed; the saturation of the image can be improved, the image is vivid, lively and vivid, and the image after the fog treatment maintains accurate hue and natural appearance, and thus obtains good Image quality and visual experience.

Real-time video fogging technology has strong engineering capabilities. The fogging technology can be applied to various resolutions including megapixel high-definition images; real-time accurate fogging can be ensured at various resolutions; real-time evaluation of the current fog concentration can be performed according to the target scene and adaptive adjustment can be achieved. Fog intensity, without fear of changes in the scene of the fog; because the fog technology can get accurate depth of field information, non-uniform fog in the same scene can be accurately removed without leaving haze.

The real-time video fogging function has been initially implemented on some cameras, and the actual collected fogging effect has been significantly improved in details, transparency, and color.

Real-time fogging technology can be combined with video compression and intelligent analysis technology to bring greater value to it. As the current mainstream video compression algorithms are lossy compression, the lower contrast details in the image will be damaged, and the foggy video is generally low in contrast and less in detail, and therefore is often blurred and cannot be encoded and compressed. restore. The use of real-time fogging technology can effectively enhance the image contrast and detail, ensure that valuable information is not lost in encoding compression, and significantly improve information effectiveness. Similar to smart analysis, the image quality of real-time fogging technology can significantly reduce the error rate of the analysis results, especially the missed report rate, and greatly improve the practicality of the intelligent analysis system.

With the development of industry and its impact on the climate, haze has increasingly become a common weather phenomenon, which has a great impact on the picture quality of outdoor application monitoring systems. At present, in practical projects, radar, infrared, and other means are used to sense and monitor targets in a hazy climate. Due to technical and cost constraints, radar, infrared, etc. have no ideal solution in the field of video surveillance. The emergence of real-time video fogging technology can bring a lot of value to the field of video surveillance.

From the perspective of application scenarios, the real-time video fogging technology can be used in various outdoor applications, such as the location of highway accident-prone areas and highway bays; the auxiliary driving facility monitoring area for buses; the focus of public security agencies Locations and regions; key monitoring areas for power plants and power transmission equipment; primary and secondary school campuses, city commercial centers, and city squares. From the perspective of the application industry, including the transportation industry, public security industry, education, aviation, digital products, remote sensing image processing, food safety monitoring, and even including special military applications. From the point of application of products and solutions, real-time video fogging technology can be applied to the front camera, fast ball fog and image quality in the field of security monitoring; can be applied to DVR to enhance the image quality; can be applied to Large-screen display (DLP Video Wall/LCD Video Wall) to enhance its color saturation and image quality; can also be used for embedded client software to enhance the preview image quality.