I really want to ask: How is the ban on honking captured?

With the acceleration of urbanization, traffic problems have increasingly become one of the challenges faced by many cities. In order to alleviate noise pollution and improve the urban environment, more and more cities have begun to implement "no honking" regulations. However, how to effectively monitor drivers' behavior, especially when it is impossible to enforce the law on the spot, has become a major problem.

Fortunately, the rapid development of modern technology has provided new ideas for solving this problem. However, have you ever wondered how the prohibition of honking is captured?

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Noise pollution and the origin of the "no honking" rule

Noise pollution in cities mainly comes from transportation, especially car horns. Studies have shown that long-term exposure to high-decibel noise will not only affect people's hearing health, but also lead to anxiety, insomnia, cardiovascular disease and other problems. The World Health Organization (WHO) points out that continuous noise exceeding 65 decibels will pose a threat to human health, and the sound of car horns in cities often exceeds this standard.

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In addition, traffic noise also seriously affects the quality of life of urban residents . Especially in schools, hospitals and residential areas, frequent honking interrupts normal study, rest and work, becoming a chronic problem in urban management. Therefore, many cities have introduced "no honking" regulations, hoping to reduce noise pollution by strictly restricting honking behavior.

In order to solve the problem of noise pollution, many countries and cities have passed legislation to clearly prohibit vehicles from honking their horns in specific areas. For example, in China, many cities have designated urban main roads, school areas, residential areas, etc. as no-honking areas. In these places, drivers are only allowed to use their horns in emergencies, and honking in other situations will be punished.

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Although this regulation provides a legal basis for urban noise control, how to supervise and punish violators has become a difficult problem in law enforcement. Faced with the movement of a large number of vehicles at different times and locations, traditional manual law enforcement methods are inefficient. For this reason, the "automatic capture" system relying on technological means came into being.

The principle of the technology to prohibit honking

To capture drivers honking their horns illegally, two key problems need to be solved: how to accurately identify the source of the horn, and how to associate the horn with a specific vehicle. To address these two issues, scientists and engineers have developed a complex acoustic recognition and monitoring system.

1

Acoustic Positioning Technology

The sound of a whistle is a high-frequency sound that is transmitted through sound waves. In order to accurately locate the source of the whistle, acoustic positioning technology becomes the core. The basic principle of this technology is to use an array system composed of multiple microphones to determine the source of the sound by analyzing the transmission time difference of the sound wave.

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Specifically, the system is equipped with multiple high-sensitivity microphones, usually three or four, forming a two-dimensional or three-dimensional microphone array. When a vehicle honks, the sound waves will reach these microphones in different time sequences.

By comparing the time difference when each microphone receives the sound, the system can accurately calculate the location of the sound source, that is, which car is honking at a specific location, based on the propagation speed of the sound wave and the time difference formula.

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This technology is similar to triangulation , which uses the time difference and sound intensity at different points to calculate the location of the sound source.

2

Sound feature recognition and filtering

The sound of a car horn is a sound with a specific frequency and sound wave shape, but in the city, other noises such as engine noise, pedestrians talking, and construction noise can also interfere with the system's recognition. Therefore, the horn capture system needs to have a good sound feature recognition function to accurately distinguish the horn from other noises.

The system uses a machine learning algorithm to input a large amount of vehicle horn sound data in advance for training, so that it can recognize the specific frequency and waveform characteristics of the horn sound. Once the system detects a sound that meets these characteristics, it will start working and capture relevant data.

3

Correlation between sound source and vehicle

Another difficulty in capturing honking behavior is accurately matching the sound source to a specific vehicle. To achieve this, the system usually combines acoustic positioning technology with video surveillance technology.

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When a horn sound is captured, the acoustic positioning system first determines the specific location of the sound source. At the same time, the high-definition camera installed on the road will capture the corresponding vehicle image based on the location of the sound source. By matching the location of the sound source with the camera shooting angle, the system can determine which car made the horn sound.

4

Vehicle information capture and processing

After determining the vehicle that honked, the system will automatically perform license plate recognition on the vehicle. Modern traffic surveillance cameras generally have high-definition and night vision capabilities, which can clearly capture license plate numbers in various lighting conditions. After recognizing the license plate, the system will record and save the license plate information together with the honking behavior as a basis for subsequent penalties.

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Some more advanced systems can also automatically upload data to the backend of the traffic management department for further processing. These data include the specific location of the vehicle, the time of the horn, the sound source location data and the vehicle's license plate information, ensuring the accuracy and traceability of the entire law enforcement process.

References

[1]https://mp.weixin.qq.com/s/r4K5msWI-9CNkZGRYqpQsQ

[2]https://mp.weixin.qq.com/s/Lxs1nvywJUmo3660eaXBiQ

[3]https://mp.weixin.qq.com/s/PPBuxi3CGXyaaoqNDLliaQ

[4]https://mp.weixin.qq.com/s/7kC0r5nH2n122DZ3jlUBEw

[5]https://www.sohu.com/a/231633237_389742

[6]https://www.thepaper.cn/newsDetail_forward_27373336

[7]https://www.sohu.com/a/409077885_477577

Planning and production

Source: Science Popularization (ID: lxkp-cstam)

Editor: Yinuo

Proofread by Xu Lai and Lin Lin