By connecting an external hard drive to your computer or even your smartphone, you can uninstall content that may be important but you don’t want to delete it. Even better, you can use your external hard drive as a backup solution to ensure that your important files are not lost, if your drive crashes or worse, you are being hacked. Technology companies are clearly seeing significant opportunities for external hard drives. You may be overwhelmed when you peruse on the shelves of Best Buy or view your choices on Amazon. Therefore, we have compiled the following list of excellent external hard drive options. They vary in price and functionality, but they can all be used to store valuable content.
DVR is a video surveillance device that has gradually developed in recent years with the development of computer technology. In the security industry, tape-based long-delay video recorders are commonly used in traditional video surveillance projects. These video recorders use tape as a carrier for storing video data. Video data is stored in an analog manner. After repeated copying of the video signal, the signal attenuation is severe. Video tapes take up a lot of storage space, and maintenance and data retrieval are troublesome. With the development of computer technology, hardware and software technology updates provide new ideas for the storage of video data.
Domestic DVR products are mainly made in China, PC-type DVR technology is mature, but there are no brand products, more are users or engineers to assemble themselves, and the entry threshold of embedded DVR is higher, mainly Brand-based. PC-type DVR can be subdivided into two types: acquisition card (also known as soft pressure card) and compression card (also known as hard pressure card). Due to technical factors, embedded DVRs are still dominated by products with less than 16 channels of video input, and embedded products higher than 16 channels are rare.
The outstanding features of DVR are reflected in the following aspects:
1. Implemented digital high-fidelity storage of analog programs
2. Comprehensive input and output interface
3. A variety of optional image recording levels
4. Large-capacity long-term program storage, strong scalability
5. The system itself is stable
6. Perfect reservation recording/playing program function
7. Powerful network information appliance center
8. Provides a convenient way to manage recorded programs
9. Provide any way you want to play
Car DVR can be customized for various functions according to different industry application requirements.
Customized function analysis of passenger operation industry: In addition to the simple vehicle video surveillance function, the passenger operation industry needs wireless network video surveillance (to understand the real-time situation inside and outside the vehicle), GPS satellite positioning, vehicle scheduling, vehicle voice announcement station, Vehicle driving information record, multimedia entertainment advertising and other functions.
Police vehicle customization function analysis: The main functions of the public security industry on the car DVR are: video surveillance, wireless network transmission, and pan/tilt control. The traffic police pay more attention to how to carry out illegal evidence collection. The main needs are: license plate recognition, blacklist comparison and so on. Industries such as urban management and transportation management also have similar needs to traffic police.
Financial industry custom function analysis: The financial industry’s money-carrying vehicles require the car DVR to work stably and reliably, and can upload video and alarm information to the management center platform in real time in the event of an emergency, and can interact with the monitoring center platform.
All 3.5-inch hard drives contain two motor systems (spindle motor and magnetic arm motor), so when the hard disk is powered up, it is similar to the case where the motor is powered on: it will have a large start at the initial time of power-on. Current to complete the hard drive boot. If the external power supply system of the hard disk does not guarantee sufficient current support when the power is turned on, the hard disk will fail to boot, resulting in the hard disk being unavailable. And if this happens many times, it is easy to cause damage to the hard disk.
Since the power supply of the hard disk motor is satisfied by the external power supply system DC 12V, the DC current of 12V is used as the standard when evaluating the starting current of the hard disk. The startup current of a normal PC hard disk is generally between 2.8A and 3.2A. The SDVR dedicated hard disk has a startup current of up to 2.0A.
Since SSDs are not suitable for frequent erasing and are costly, monitoring storage has always been the world of disk. Toshiba also built its own line of surveillance hard drives. Among them are audio-visual streaming hard drives and surveillance hard drives. The audio-visual streaming hard drives have a capacity of up to 3TB and an average trouble-free running time of up to 800,000 hours. They are suitable for 1-4 bay configurations. Its latest surveillance hard drive products can support at least 32 high-definition cameras running 24×7 per day. In addition, the monitor hard drive is also equipped with a rotating vibration (RV) sensor, especially suitable for RAID and multi-drive monitoring platforms. .
The monitoring hard drive has now made a very rapid development as an important branch of the hard drive, making the entire monitoring system more efficient. On the other hand, from the perspective of the development of the entire industry, the rise of concepts such as safe city and smart transportation has further contributed to the monitoring of the hard disk market.
The embedded DVR has the characteristics of simple and compact structure, small size, more professional and more practical. The status of embedded DVRs: There are very few companies with independent research and development capabilities; domestic brands are the mainstay; they are developing rapidly; they are recognized as stable and reliable products.
Embedded DVR features
? 1, using embedded real-time operating system, more professional and more practical;
? 2. The software is solidified in FLASH and has non-modifiability;
? 3. The structure is simple and compact, and the volume is small.
Video recording technology In the DVR, the recording function is connected with many other functions, such as playback function, network function, backup function, etc. Therefore, what kind of recording technology is used is directly related to the function of the entire DVR and the failure rate of the hard disk. Video recording technology is divided into two aspects: 1) What kind of file system is used, which is usually related to the operating system used, and it is not easy to choose independently; 2) How to apply the system to the advantage of the file system under the premise of the selected file system While avoiding its weaknesses, it affects the entire system.
At present, PC-type DVRs are generally based on Windows systems, and the file system is generally NTFS or FAT32; the file system used by the embedded DVR has a close relationship with the embedded control system selected by the manufacturer. At present, embedded operating systems used in embedded DVRs include pSOS, Embedded Linux, vxWorks, etc., and the file systems used are more types, such as MS-DOS compatible file systems, UNIX compatible file systems, and Windows compatible file systems. There are also various proprietary file systems and so on. Which file system is selected as the file system in the embedded DVR depends on many factors, such as the company’s research and development capabilities, financial resources, and the characteristics of the file system itself. It should be said that the choice of any file system will not hinder the implementation of the recording function in the embedded DVR. Some companies even organize their own file systems to meet their needs. Of course, we do not agree with this, because it may take a long time to extend the time to market. In addition, this approach is not in line with modern society. The trend of division of labor is becoming more and more detailed and more professional, and it is difficult to be as reliable as the file system introduced by professional software vendors.
A traditional rotating hard drive is a basic non-volatile memory on a computer. That is to say, the information that closes it does not “disappear” when the system is shut down, which is different from the data stored in RAM. The hard drive is essentially a magnetically coated metal disc that stores your data, whether it’s a weather report from the last century, an HD copy of the original Star Wars trilogy, or your digital music collection. When the disc is rotated, the read/write head on the arm accesses the data. An SSD is functionally a hard drive, but the data is stored on an interconnected flash chip that retains data even when there is no power. The types of these flash chips are different from those used in USB thumb drives and are generally faster and more reliable. Therefore, SSDs are more expensive than USB thumb drives of the same capacity. However, like thumb drives, they are typically much smaller than HDDs, giving manufacturers greater flexibility in designing PCs. Although they can replace traditional 2.5-inch or 3.5-inch hard drive bays, they can also be installed in PCI Express expansion slots or even directly on the motherboard. This configuration is now available on high-end laptops and all MFPs. . (These SSDs mounted on the board use a form factor called M.2. The best M.2 solid state drive.)
With the increasing popularity of industrial security monitoring systems and even personal security monitoring systems, security monitoring is no longer exclusive to users in the municipal, transportation, hotel and other industries. Security monitoring systems have already entered the homes of ordinary people. Monitoring storage is a very special area, and its application features continuous writing of large amounts of data. This puts three requirements on the hard disk. First, it needs 24 X 7 and guarantees continuous stability. Only in this way can the video image data be completely recorded. Secondly, power consumption, because it needs 24 X 7 operation, monitor the hard disk. Strict control of power consumption is required to reduce the cost of the storage solution; finally, high capacity. This is also a basic requirement because the application will continue to write data to the hard disk. Therefore, the monitoring hard disk is a product with a large capacity.