#How to choose an intelligent security camera? Complete analysis of chips, sensors, and algorithms
>Technical solution | Approximately 1200 words
This camera claims to be AI intelligent detection, but when a tree leaf shakes, it will sound an alarm. It pushes 200 false alarms a day, and after two weeks, I will turn off the notification. "- This is the original words of a community property manager. The intelligent security camera market is a typical disaster area with "beautiful parameters and a disappointing experience".
A truly useful intelligent security camera is not supported by an AI tag. It is a comprehensive system consisting of hardware, algorithms, and protocols. Let's take a look from four dimensions: CMOS sensors, AI chips, night vision solutions, and ONVIF protocol.
##CMOS sensor: the foundation of image quality, not the higher the pixel, the better
The sensor selection for security cameras is completely different from that of mobile phones. Mobile phones pursue high pixel resolution (enlarging and cropping after shooting), while security cameras pursue low light performance and wide dynamic range .
There are three key indicators:
-Target surface size: Under the same pixel size, the larger the target surface, the larger the photosensitive area of a single pixel. The light intake of 1/1.8 inch is more than twice as high as that of 1/2.8 inch, and the difference in nighttime image quality is significant.
- Minimum illuminance : The unit is lux, indicating how dark the light can still be captured clearly. A nominal 0.001 lux is required to produce color images under moonlight, but it doesn't matter when viewing black and white scenes under infrared fill light.
-WDR Wide Dynamic: In scenes with high light ratios such as the entrance of a shopping mall or the entrance and exit of an underground garage, WDR needs to capture both bright and dark areas clearly. 120dB WDR is the watershed, and backlit scenes below this value are either overexposed or dead black.
Summary: 2 million pixels+large target surface+low illumination is much better than 8 million pixels+small target surface+poor low illumination.
##AI chip: computing power is not everything, model efficiency is
The AI chip of the security camera is responsible for completing tasks such as facial capture, license plate recognition, and area intrusion detection locally. Many buyers only look at 'how many TOPS' (computing power units), but this is only half of the story.
For example, a truck can hold 10 tons of goods, but if it only transports one express box at a time, no matter how powerful the horsepower is, it is a waste. The same goes for AI chips - computing power is "how fast they can run", and model efficiency is "whether they run on the point".
There are three key points to consider:
-Model adaptation: Do manufacturers have their own lightweight models? The same detection task can result in a 3-5 times difference in efficiency
-Multi algorithm parallelism: Can we run face detection, area intrusion, and license plate recognition simultaneously without dropping frames
- Power consumption : Cameras with AI chips typically consume 30% -50% more power than regular cameras, and if the cooling design cannot keep up, they are prone to crashing
##Night vision solution: How to choose infrared light, starlight level, warm light full-color
There are three levels of night vision solutions for security cameras:
*Infrared Night Vision * (Basic): Two infrared LED fill lights, black and white image, effective distance of 20-30 meters. Lowest cost, suitable for scenes without color requirements (underground garages, warehouses).
*Starlight level * (mid-range): With a large aperture lens, large target area sensor, and low light performance, color images can still be produced in low light. City night scenes and streets with street lights, starlight level cameras basically do not need to cut infrared, the image remains in color, and the effect of identifying people and cars is much better than infrared black and white.
*Warm light full-color * (high-end): Replace infrared with warm light LED fill light, and capture full-color images even at night. However, supplementary lighting can attract mosquitoes and insects, and residential areas may cause complaints about light pollution. When selecting a location, it is important to weigh the pros and cons.
Selection suggestion: Starlight level for urban outdoor use, infrared for indoor/underground use, warm light full-color for license plate recognition needs (license plate color cannot be seen clearly under infrared).
##ONVIF protocol: Can cameras from different brands be managed on the same platform
This is a pitfall that large projects are prone to. ONVIF is an industry standard protocol, theoretically, any ONVIF certified camera can be connected to an NVR or management platform that supports ONVIF.
But 'supporting ONVIF' has three levels:
-Profile S: Basic video stream, capable of viewing images and PTZ control
-Profile G: Supports playback and video retrieval
-Profile T: Supports advanced features such as H.265 and intelligent encoding
If your project requires cross brand mixing, you must confirm that all devices support at least ONVIF Profile S and that the target NVR has undergone compatibility testing for the brand you want to connect to. Brands outside the whitelist may have secondary development workload.
##Selection Practice Checklist
|Scenario | Sensor Suggestions | AI Requirements | Night Vision Solution | ONVIF|
|------|-----------|--------|---------|-------|
|Community perimeter | 2 million/1/1.8 inches | Area intrusion+humanoid detection | Starlight level+infrared | Profile S|
|Building lobby | 5 million/1/2.5 inches | Facial capture | Adequate indoor lighting | Profile S|
|Parking lot entrance and exit | 2 million/1/1.8 inches+WDR | License plate recognition | Warm light full-color | Profile T|
|Warehouse/Workshop | 2 million/1/2.8 inches | Area Intrusion | Infrared Night Vision | Profile S|
##Say one more sentence
The selection of security cameras is not based on whose parameter list is longer, but on the one that best matches your specific scene - lighting conditions, installation height, and target recognition. V-Well Technology has accumulated rich industry experience in security imaging modules and chip solutions. If you are working on security project selection, please feel free to contact us to discuss practical scenarios.
To learn more about security imaging solutions, please visit the official website of V-Well.