Regarding the problem of identifying license plates at night, many cars enter and exit the community and parking lots at night. They can’t scan out or scan the license plates incorrectly, which is annoying! There are many tricks to explain clearly in this. We need to explain carefully what is going on and how to solve these problems… First of all, we have to understand what the recognition of night license plates is. Simply put, it is to use special cameras and computer systems to accurately "see" the characters on the car license plate on the dark nights and dark nights, and then record them and pass them to the system, so that the access control and charging systems can work normally without having to let the security guard register manually there one by one, which can save a lot of trouble and speed! Of course, the light at night is so poor, it is completely different from the daytime light and can see clearly, so its technical requirements, equipment performance, etc. are much higher than that during the day!
1. Let’s talk about the camera first : the light is dark at night, so the camera must be able to "see" it! So you have to use those with infrared lights or starlight cameras. The infrared may be fine during the day, but at night, you rely on infrared lights to illuminate the license plate, but sometimes it will reflect and be white; starlight, even if the light is not very good, it can capture a clearer picture, but the price may be a little higher!
2. Then there is the problem of fill light : relying on the camera alone may not be enough. In many cases, additional fill lights must be installed, such as white LED fill lights, or special infrared fill lights. The white fill light lighting looks a bit like the daylight, which can make the license plates taken very clearly, but they are a little dazzling to the passing drivers; although the infrared light is not very dazzling, the license plate number sometimes cannot be reflected due to reflection! Provide global procurement services for weak current intelligent products!
3. Also have the installation angle and position : the camera is not enough to be installed high or low! If you install it too far, you need to adjust the focal length. If you install it too close, the car will not be able to take a complete picture in a flash. Generally, you should pat the license plate on the front face, and don’t shoot it diagonally. If you shoot the license plate on the side, it will deform and the letters of the numbers will be crooked, so it will be difficult to recognize the software! It’s okay to have a little crooked body, but the license plate is the most important!
4. Talk about algorithm recognition ability : Even if the camera is taken clearly, you have to rely on the algorithms in the computer to "read" these numerical letters at night. Sometimes the license plate is dirty, or the reflection makes the words on the license plate light and dark, covering them. At this time, the algorithm must be smarter, be able to process the blurry pictures clearly, and turn the crooked license plates forward; for a complex background, there are street lights, neon lights and flashes beside them, and you have to ignore them. Some advanced algorithms can still be learned! The more license plates you see, the more accurate the identification will be!
5. Is the hardware equipment sufficiently configured : the relatively low-level identification equipment used to be old may have gone on strike or refused to recognize it at night! Nowadays, new devices generally use faster chips. If the processor responds quickly, they can process the pictures taken in one go, and the car will not wait too long. The resolution is also enough! A camera with only a few hundred thousand pixels can never be able to see the alphanumeric numbers on the license plate clearly at night. At least one pixel is more than 2 million pixels. The higher the higher the, the clearer it is. Of course, the storage must be increased!
Question: Why do the license plates in the front sometimes illuminate, but the license plates in the back of the SUV cannot be seen clearly and they are always identified incorrectly? -The main reason is that it has a lot to do with the model! Most SUVs are taller and have a little upturned buttocks. If the camera is installed directly to the front car license plate, the position may be a bit low and flat. When you take a photo of the license plate at night, the angle will be too upward – some license plates will hide under the bumper at the high point – and you may only be able to take half of the license plate. The fill lights and lights just didn't look right in the middle of the back license plate. In order to save trouble, some manufacturers only installed a camera on the aisle. There is no problem with the front license plate in front. After a while, the back license plate followed. The angle of the camera was not aligned, and it was dark and could not be identified. Then adjust the camera angle and lift it up by about 5 degrees, or install a small probe at the back to take pictures of the rear license plate!
Q: It’s so easy to identify license plates on rainy nights. Is there any practical solution? Isn’t it just a few sprays of defog deodorants? It is easy to have water beads on the lens on rainy days, so choose a camera with wiper function, or add a layer of specially coated anti-splashing film outside the lens*-water cannot be attached and will slip away in an instant! Filling light is also very important. There are narrow-angle fill lights for rainy days. Try to shine on a small part of the license plate, so as not to let the rain reflect the bright spots everywhere—and also, clean the camera and wipe it clean! ! Wipe it clean and take pictures to be clear and accurate! The drainage pipe on the ground needs to be done! ! The ground area is too deep – the water splash may flood the lower half of the camera.
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