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The first category is professional R&D and production. Such companies independently research and develop design products. At least 3 years of experience in R&D of on-board DVRs is available. Such companies may have relatively few products, but product quality can be trusted and customers can get a lot of Follow-up technical support;
The second category is the production and processing category. Such companies generally use the public board program for production. The public board program is provided by the chip manufacturers for the promotion of chips. It evolved from the functional demo board. Generally, it only achieves the functions, but the stability is difficult. It is guaranteed that such enterprises reduce costs through mass production, but product quality and follow-up technical support are often unsatisfactory;
The third category is OEM manufacturers. Such manufacturers purchase products from other companies and sell them on their own company's brand, which is almost a blank in technology.
Another car DVR market there is still a freak, they are generally doing ordinary desktop DVR, the ordinary desktop DVR simply modified as a car hard disk recorder to sell, this product is not a professional car DVR, so this Manufacturers do not discuss.
Professional car DVR R & D manufacturers are the premise to choose the product, then how to judge the pros and cons of the product? The following will analyze the product function, file system, power handling, and shockproof processing. The stability of the product is a comprehensive factor. It is not like the power supply design, or the shockproof design, or the file that some manufacturers advertise the most important. System design, in fact, every point is very important, any design defects will affect product stability.
First, the function of the vehicle-mounted hard disk video recorder product must be clear video: video data to achieve D1 (720 * 576) resolution, if the video is not clear then there is no sense of monitoring.
Secondly, there is a need for power-saving functions: When the vehicle is stopped, if the vehicle-mounted hard disk video recorder is operated for a long time, it will cause a certain loss to the car battery, which will easily lead to the loss of the vehicle's power. This will reduce the battery life and increase the cost of the car. Maybe some engineering firms will solve the problem by connecting the power supply to the switch. However, the driver can control the switch of the device and cannot perform comprehensive monitoring. In addition, the power failure of the device will cause great damage to the hard disk and reduce the hard disk usage. Life expectancy increases costs. The products of Nanjing Codesaw Co., Ltd. fully take this into consideration, and the power consumption is less than 1W in the power-saving state.
The third need to have automatic video recording function: We all know that letting customers press the video key is a waste of time, but the customer often forgets the key click on the actual use, and then tells you that the device does not have video data, the customer is God, so the human cost Time and cost are increasing, making the product more humane, which is also a key point for the company when designing the product.
Fourthly, there is a need for anti-crash function: the on-board environment is complex, and all kinds of unexpected situations may occur. This ensures that the equipment can automatically recover after an accident. This is also an important condition for choosing a product.
Fifth, we must consider the ease of data backup: In the event of an accident, the customer needs to save the video data. When selecting a vehicle DVR product, it is necessary to consider the convenience of the backup. It requires not only a direct file copy function but also a file format conversion. Features for general playback software to play. In addition, the cost of backup equipment needs to be reduced as much as possible.
Second, car DVR power supply design Car DVR power supply design is very particular about. Because the car's main source of power is from the car battery, the output voltage of the battery during starting and running is very unstable, especially when the ignition voltage is pulled by the engine very low, the voltage may rise when the throttle is pressed heavily Very high, the occasional instantaneous voltage may exceed 48V, so the power supply design of the vehicle DVR products is required to adapt to this environment. The operating voltage range of the company's car DVR products is 10V~48V, and the impact voltage range is 7V~60V. Only in this way can the equipment work properly under low voltage, and it can also protect the equipment from being damaged in case of instantaneous high voltage. .
Third, car DVR file system design Car DVR can be said to be a new product, coupled with many manufacturers do not have the design experience of the file system, currently on the market a lot of car DVR products are extended using ordinary DVR file system, this type The file system is very fragile and can not cope with the various abnormal situations that occur in the use of vehicles, such as incomplete files caused by sudden power failure, non-recognition of discs when replacing hard disks, and problems such as broken files cannot be played normally. Based on more than ten years of file system design and four years of experience in R&D of on-board hard disk recorders, Nanjing Codesuo has developed a dedicated file system for on-board hard disk recorders. It has strong robustness and stability and will not be subject to abnormal conditions. Causes the system to not work properly.
Fourth, car DVR anti-vibration design Rubber anti-vibration car DVR is more traditional shock-proof way, but because of the poor anti-aging rubber, gradually replaced by spring shock, the spring shock in the best wire spring, the code Shuo company The vibration damping device uses military technology and high-intensity anti-vibration design. Can effectively attenuate three-dimensional six-way impacts of up, down, left, right, front and back. This type of vibration damping device has a wide range of vibration frequency absorption, and the vibration energy absorption from the frequency range of 15Hz to 1,500Hz can reach 98.5%. The damping springs are made of special alloy steel materials, which are resistant to deformation and fatigue and have a field life of more than 30 years. In addition, the military rubber hard disk bracket is equipped with a secondary vibration damper in the hard disk box, and the absorption of ultra-low frequency vibration at frequencies below 15 Hz is particularly effective. Some products are designed to be small in size and reduce the shock-proof design requirements, which will have a great negative impact on the stability of the product.
To sum up, the choice of car DVR products must choose a relatively strong technical strength of the manufacturers, product features should be the pursuit of practicality, can not be a greedy what function should be, often some "advanced" features but manufacturers only gimmick, said It is not available until the product is phased out. Stability is the fundamental of DVRs in cars. It is not possible to reduce the quality of products because of price factors. Otherwise, the follow-up maintenance costs will far exceed the money saved when the products are purchased, and the mental annoyance it brings is not constant.
How to choose a car hard disk recorder?
The current car DVR manufacturers can be roughly divided into three categories: