The origins of high-definition video in China's market can be traced back to 2008, when high-definition came out, it immediately attracted the attention of all parties. The market has also opened up all of a sudden and there are numerous high-definition products and solutions. So, what is HD, why can it attract so many people's attention and how does it actually work? Today, we enter the world of HD cameras with doubt.
First, set off your hijab. What is the high school academic theory:
Talking about HD, we mainly talk about the clarity of the back-end display. Its various products have similar places. HD is mainly divided into standard definition television and high-definition television in the field of digital television display. This applies to all types of displays. Standard definition television mainly refers to the digital television system with the image quality equivalent to the current conventional analog color television system. The resolution is about 500 television lines and the code rate is about 5Mbps. High definition television (HDTV) refers to the level of clarity. The degree and vertical resolution are about twice that of current analog color television systems, and the 16:9 aspect ratio digital television system has a resolution of about 800 television lines or more and a code rate of about 20 Mbps.
According to the International Telecommunication Union in ITU-RBT. Recommendation 1201 proposes several standards for ultra-high definition imagery (HRI). The basic elements are the minimum image resolution of 1920x1080. HRI is divided into four levels, including HRI0, HRI1, HRI2, and HRI3, with resolutions of 1920x1080 respectively. , 3840x2160, 5760x3240, 7580x4320.
According to the above definition, it can correspond to video surveillance. Generally, the analog and digital cameras can monitor up to standard definition. If digital processing is used, the maximum resolution of analog cameras can reach 4CIF or D1 resolution, about 400,000 pixels. The resolution is between 300 and 500 lines; IP monitoring using high-definition network cameras, if you want to achieve the definition of 800 TV lines, then the resolution of the network camera must reach at least 1280x720 standard, about 900,000 pixels, is a mixture of modules More than double the monitoring; if a 2-megapixel network camera is used, the requirements for ultra high-definition images are met. The network camera with an aspect ratio of 16:9 corresponds to a resolution of 1920x1080 and a network with an aspect ratio of 4:3. The camera has a resolution of 1600x1200.
Academics have always spoken with data. However, in practical applications, high-definition surveillance cameras will always have different sounds from users. The so-called "practices come true". When discussing high-definition cameras, we may wish to listen to the perception of the practitioners.
Practitioners' reliable knowledge:
Security industry's high-definition video is proposed in comparison with traditional SD surveillance. At present, many concepts in the security industry are still not uniform and the adopted technical standards are different. However, many standards for broadcasting and television are used. At this stage, there are two concepts regarding the resolution of high-definition surveillance, namely, megapixels and 720p/1080i/1080p, and the resolution to reach these two standards is high definition.
However, in practical applications in the industry, any surveillance camera with a pixel resolution of more than 1.3 million and a resolution of 1280×960 is a high-definition camera.
Second, the flowers for the 啥 啥 高清 高清 高清 高清 高清 高清 such high-definition security cameras since the debut, has been subject to all the love. Its widely used projects in finance, telecommunications, government, safe cities, schools, airports, and traffic monitoring are all currently implementing high-definition monitoring of Beijing's municipal traffic monitoring systems. Why is the "red fire" high-definition surveillance camera so "fire"?
High-definition monitoring effects make monitoring more "favorable"
High-definition surveillance not only has high-definition picture quality, but also has a wider field of vision while satisfying high-quality monitoring. An ordinary camera can achieve a monitoring range of 3.7 meters while a high-definition camera can reach 7.4 meters. At present, large-scale projects such as government and engineering have a wide range of monitoring and require high visual and image quality. Ordinary standard definition cannot reach this standard, does not achieve the monitoring function, chooses to use the high-definition surveillance camera.
The rigid demand of the market allows HD to live in HD, and the most fundamental reason is customer demand. In large-scale projects, if the engineering companies take the digital high-definition camera to the market, they will achieve higher customer satisfaction, higher engineering profits, and higher profits because of their good monitoring effect and high reliability. The project competition wins.
Second, high-definition surveillance cameras can make projects more profitable. We know that HD surveillance is digital and networked, and analog surveillance can only be standard definition. Although high-definition digital HD monitors have high quality and high prices, the overall cost is not much higher. Because in the transmission process of high-definition monitoring, data and power supply are combined and transmitted through switches, which can save the wiring of wires.
High-definition surveillance cameras use four-core cable instead of coaxial cable, which also makes the wire cheaper. The use of inexpensive fiber optic transceivers instead of expensive optical transceivers has further reduced the cost. In addition, since digital HD network cameras output digital signals that are not susceptible to electromagnetic interference, there is no need to add anti-jamming devices in strong magnetic fields, which saves costs. This also solves another problem of surveillance cameras, namely, anti-interference. The problem.
Storage has always been a problem that is more important in the field of surveillance cameras. The back-end host of the HD camera does not require a DVR card. Digital HD network cameras output digital compressed video signals instead of analog signals. Therefore, the back-end host does not require analog-to-digital conversion, does not need to use CPU resources for video compression, and does not need to insert a DVR card in the host. This saves costs and is simple and practical.
When a digital high-definition camera monitors wide-angle ranges such as workshops, plazas, and roads, due to its wide range of monitoring, high definition, and strong anti-interference ability, it is possible to have several traditional analog cameras on top of it, but also to save the wire With equipment.
Summary: At the wedding party, everyone wants to see how beautiful the bride under the hijab is. In the same way, the popularity of high-definition surveillance cameras is not only caused by its own advantages, but also people's ability to achieve high-definition, anti-jamming and other functions on video surveillance. An expectation. As technology continues to advance, I believe that in the field of video surveillance, high-definition is just a beginning. In the future, more and more excellent products will come out.
First, set off your hijab. What is the high school academic theory:
Talking about HD, we mainly talk about the clarity of the back-end display. Its various products have similar places. HD is mainly divided into standard definition television and high-definition television in the field of digital television display. This applies to all types of displays. Standard definition television mainly refers to the digital television system with the image quality equivalent to the current conventional analog color television system. The resolution is about 500 television lines and the code rate is about 5Mbps. High definition television (HDTV) refers to the level of clarity. The degree and vertical resolution are about twice that of current analog color television systems, and the 16:9 aspect ratio digital television system has a resolution of about 800 television lines or more and a code rate of about 20 Mbps.
According to the International Telecommunication Union in ITU-RBT. Recommendation 1201 proposes several standards for ultra-high definition imagery (HRI). The basic elements are the minimum image resolution of 1920x1080. HRI is divided into four levels, including HRI0, HRI1, HRI2, and HRI3, with resolutions of 1920x1080 respectively. , 3840x2160, 5760x3240, 7580x4320.
According to the above definition, it can correspond to video surveillance. Generally, the analog and digital cameras can monitor up to standard definition. If digital processing is used, the maximum resolution of analog cameras can reach 4CIF or D1 resolution, about 400,000 pixels. The resolution is between 300 and 500 lines; IP monitoring using high-definition network cameras, if you want to achieve the definition of 800 TV lines, then the resolution of the network camera must reach at least 1280x720 standard, about 900,000 pixels, is a mixture of modules More than double the monitoring; if a 2-megapixel network camera is used, the requirements for ultra high-definition images are met. The network camera with an aspect ratio of 16:9 corresponds to a resolution of 1920x1080 and a network with an aspect ratio of 4:3. The camera has a resolution of 1600x1200.
Academics have always spoken with data. However, in practical applications, high-definition surveillance cameras will always have different sounds from users. The so-called "practices come true". When discussing high-definition cameras, we may wish to listen to the perception of the practitioners.
Practitioners' reliable knowledge:
Security industry's high-definition video is proposed in comparison with traditional SD surveillance. At present, many concepts in the security industry are still not uniform and the adopted technical standards are different. However, many standards for broadcasting and television are used. At this stage, there are two concepts regarding the resolution of high-definition surveillance, namely, megapixels and 720p/1080i/1080p, and the resolution to reach these two standards is high definition.
However, in practical applications in the industry, any surveillance camera with a pixel resolution of more than 1.3 million and a resolution of 1280×960 is a high-definition camera.
Second, the flowers for the 啥 啥 高清 高清 高清 高清 高清 高清 such high-definition security cameras since the debut, has been subject to all the love. Its widely used projects in finance, telecommunications, government, safe cities, schools, airports, and traffic monitoring are all currently implementing high-definition monitoring of Beijing's municipal traffic monitoring systems. Why is the "red fire" high-definition surveillance camera so "fire"?
High-definition monitoring effects make monitoring more "favorable"
High-definition surveillance not only has high-definition picture quality, but also has a wider field of vision while satisfying high-quality monitoring. An ordinary camera can achieve a monitoring range of 3.7 meters while a high-definition camera can reach 7.4 meters. At present, large-scale projects such as government and engineering have a wide range of monitoring and require high visual and image quality. Ordinary standard definition cannot reach this standard, does not achieve the monitoring function, chooses to use the high-definition surveillance camera.
The rigid demand of the market allows HD to live in HD, and the most fundamental reason is customer demand. In large-scale projects, if the engineering companies take the digital high-definition camera to the market, they will achieve higher customer satisfaction, higher engineering profits, and higher profits because of their good monitoring effect and high reliability. The project competition wins.
Second, high-definition surveillance cameras can make projects more profitable. We know that HD surveillance is digital and networked, and analog surveillance can only be standard definition. Although high-definition digital HD monitors have high quality and high prices, the overall cost is not much higher. Because in the transmission process of high-definition monitoring, data and power supply are combined and transmitted through switches, which can save the wiring of wires.
High-definition surveillance cameras use four-core cable instead of coaxial cable, which also makes the wire cheaper. The use of inexpensive fiber optic transceivers instead of expensive optical transceivers has further reduced the cost. In addition, since digital HD network cameras output digital signals that are not susceptible to electromagnetic interference, there is no need to add anti-jamming devices in strong magnetic fields, which saves costs. This also solves another problem of surveillance cameras, namely, anti-interference. The problem.
Storage has always been a problem that is more important in the field of surveillance cameras. The back-end host of the HD camera does not require a DVR card. Digital HD network cameras output digital compressed video signals instead of analog signals. Therefore, the back-end host does not require analog-to-digital conversion, does not need to use CPU resources for video compression, and does not need to insert a DVR card in the host. This saves costs and is simple and practical.
When a digital high-definition camera monitors wide-angle ranges such as workshops, plazas, and roads, due to its wide range of monitoring, high definition, and strong anti-interference ability, it is possible to have several traditional analog cameras on top of it, but also to save the wire With equipment.
Summary: At the wedding party, everyone wants to see how beautiful the bride under the hijab is. In the same way, the popularity of high-definition surveillance cameras is not only caused by its own advantages, but also people's ability to achieve high-definition, anti-jamming and other functions on video surveillance. An expectation. As technology continues to advance, I believe that in the field of video surveillance, high-definition is just a beginning. In the future, more and more excellent products will come out.
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